research article measurements of gasification ...ments with coal and char at high temperature;...

Hindawi Publishing CorporationJournal of CombustionVolume 2013 Article ID 985687 15 pageshttpdxdoiorg1011552013985687

Research ArticleMeasurements of Gasification Characteristics of Coaland Char in CO2-Rich Gas Flow by TG-DTA

Zhigang Li1 Xiaoming Zhang2 Yuichi Sugai1 Jiren Wang2 and Kyuro Sasaki1

1 Department of Earth Resources Engineering Faculty of Engineering Kyushu University Fukuoka 819-0395 Japan2 College of Mining Engineering Liaoning Technical University Fuxin 123000 China

Correspondence should be addressed to Zhigang Li zhiganglee2009hotmailcom

Received 22 January 2013 Revised 22 April 2013 Accepted 23 April 2013

Academic Editor Constantine D Rakopoulos

Copyright copy 2013 Zhigang Li et al This is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

Pyrolysis combustion and gasification properties of pulverized coal and char in CO2-rich gas flow were investigated by using

gravimetric-differential thermal analysis (TG-DTA) with changing O2 heating temperature gradient and flow rate of CO

2-rich

gases provided Together with TG-DTA flue gas generated from the heated coal such as CO CO2 and hydrocarbons (HCs) was

analyzed simultaneously on the heating processThe optimumO2 in CO

2-rich gas for combustion and gasification of coal or char

was discussed by analyzing flue gas with changing O2from 0 to 5 The experimental results indicate that O

2 has an especially

large effect on carbon oxidation at temperature less than 1100∘C and lower O2concentration promotes gasification reaction by

producing CO gas over 1100∘C in temperatureThe TG-DTA results with gas analyses have presented basic reference data that showthe effects of O

2concentration and heating rate on coal physical and chemical behaviors for the expected technologies on coal

gasification in CO2-rich gas and oxygen combustion and underground coal gasification

1 Introduction

As the increased fossil fuels consumption such as coal oil andgas leads to rapid deterioration of global environment nowa-days low-carbon economy is getting more and more atten-tion Low-carbon economy mostly linked greenhouse gasesemissions and energy usage together [1 2] The economicgrowth of energy consumption countries impels intensive useof energy and other natural resources thus more residuesand wastes discharged in the nature lead to environmen-tal aggravation China has been the second largest energyconsumption country in the world where the total energyconsumption increased from 302 million tons of standardcoal equivalent in 1960 to 2850 million tons in 2008 [3] Coalas an energy source plays an important and indispensablerole on future energy mix due to its proven stability insupply and its low cost Coal has improved its long-termposition as the worldrsquos most widely available fossil energysource with a very large resource base and economicallyrecoverable reserves that are much greater than those of oiland gas Coal is the most abundant fossil fuel in China

Present recoverable reserves occupied about 1167 of globalcoal reserves based on Key World Energy Statistics 2010 [4]ranked third in the world with potential total reserves farin excess of this amount Chinese coal consumption by theyear 2020 will be nearly 48 billion tons per year with thebulk being consumed through the combustion processesTherefore present recoverable reserves are adequate to meetthe national coal needs for many decades and potentiallymuch longer Moreover most of coal consumptions are forelectric power generations with industrial consumptions ofcoal for steam and heat and for chemical and metallurgicalprocesses being other major uses [5]

Carbon dioxide (CO2) is regarded to be the main source

of greenhouse gases emission that is a major threat of globalwarming and climate change [6] According to the Intergov-ernmental Panel on Climate Change (IPCC) approximately75 of the increase in atmospheric CO

2is attributable to

the consumption of fossil fuels [7 8] According to statisticsof the IEA (2011) [9] CO

2emission from fossil energy

consumption in China was accounted for about 19 of globalCO2emission of which coal-fired power plants occupied

2 Journal of Combustion

Gasification and combustion

(power and heat)

Coalchar

Postcombustion capture

Coalchar

Precombustion capture

Steam

Gasification or partial oxidation

(oxidoeduction) Power and heat


(oxidoreduction)

Coalchar

Coal added steam for enhancing gasification reactions

O2

O2

O2

N2

CO2 and steam

CO2 and NO119909

H2 CO CO2

High CO2

High CO2

H2 CO HCs CO2

CO2 and H2O recirculating

New O2CO2 oxy-fuelcombustion capture

Power and heat

Figure 1 Schematic diagram of three kinds of power generationwith CO

2capture

about 526 of total CO2emission in China International

Energy Agency (IEA) predicted that in 2030 China wouldemit twice as much carbon dioxide as that in 2007 providedthat CO

2emissions increase by 29 each year [10]

As stationary sources emitting large amounts of CO2

pulverized coal fired power plants could be the best candi-dates to install CO

2capture system which can be classified

into three categories in general precombustion capturepostcombustion capture and oxy-fuel strategy as shown inFigure 1 [11 12] The traditional coal fired boilers use air forcombustion in which N

2gas is 79 in volume ratio Its flue

gas includes only about 15 CO2 therefore the CO

2capture

efficiency by post-combustion system is not high [13 14]Furthermore CO

2capture cost from the flue gas using amine

scrubbing is expected to be relatively high [15] In the case ofpre-combustion capture although calorific value of oxy-firedcoal boiler is higher than that of air-fired coal boiler there is amajor disadvantage for oxygen-blown gasifier that is to buildan oxygen plant In general an oxygen plant consumes about5 of the gross power generated which is the main reasonwhy the total of plant investment for an oxygen-blown plantis somewhat higher than that of an air-blown plant [5]

As an alternative a zero-emission power plant of pul-verized coal-fired power generation in a nitrogen-free atmo-sphere most known as oxy-fuel or O

2CO2combustion tech-

nology for pre-combustion capture is one of new promisingmethods to approach the problem of CO

2separation and

capture In this technology CO2gas substitutes the role

of O2gas to improve and stimulate coal conversion and

reduce O2consumption Recently coal gasification with CO

2

and oxygen combustion technology has been investigatedfor next coal fired power [16 17] In addition this typeof pulverized coal fired power plant is mainly composedof gasifier and combustor as shown in Figure 1 Moreovergasification process of pulverized coal in the gasifier is thecore part of the technology because it determines synthesisgas product and thermal efficiency This process is also the

focus of the research in this paper moreover it has beenverified that the processes of coal in CO

2-rich gas atmosphere

mainly are divided into two temperature ranges for coaldevolatilization char formation and gasification

The implementation of these improved combustion tech-nologies for replacing N

2with CO

2in feeding gas requires

further understanding of physical and chemical characteris-tics in the process of oxidation combustion and gasificationof coal with gradually increasing temperature in CO

2-rich

atmosphere In particular reaction characteristics of coalgasification in a CO

2-rich atmosphere are required for coal

seam underground coal gasification (UCG) projects Li etal presented the comparisons in TGA experiments withbituminous coal at high temperature of 1000∘C with heatingrate of 10 to 30∘Csdotminminus1 in the mixture of O

2N2or O2CO2

with various oxygen concentrations (21 30 40 and 80) [18]and Liu presented the properties of coal chars prepared fromUK high-volatile bituminous and anthracite coals by usingTGA with heating rate of 25 to 125∘Csdotminminus1 in mixturesof O2CO2and O

2N2with O

2concentrations of 3 6 10

21 and 30 [19] However researchers did not measure fluegas and heat generation by coal combustion and gasificationThe unburned carbon content in CO

2rich atmosphere is

expected to be higher than those in air environment due toO2concentrationAuthors (Li et al 2012) [20] have presented the com-

bustion and gasification properties of Datong coal and charin CO

2-rich gas flow (5 or 10 O

2) by rapid heating with

temperature gradient of 50 to 200∘Csdotsminus1 using a CO2laser

beam In the experiments the coal conversion ratio to gaseswas measured for different coal temperature time gradientwith monitoring of CO and HC gases generated from heatedcoal particles Based on experimental results by the rapidheating of dry moist coal and mixing coal-water samplesit has been clarified that coal moisture (internal water) andexternal water of coal particles have the same function toincrease HC-gas production and decrease CO-gas amountby promoting chemical reactions between carbon or COand H

2O Consequently a possibility has been shown to

accomplish coal gasification in CO2-rich atmosphere includ-

ing enough water vapor to carry out low-cost CO2capture

Most researchers presented the results in TGA experi-ments with coal and char at high temperature however theexperimental results were restricted to HCs and CO gasifiedgases analysis and heat generation after coal gasificationInvestigation of gasification and combustion reactivity ofcoal in CO

2-rich atmosphere at high temperature HCs

CO and so forth gasified gases generations is essential forthe development of gasification technology in the futureIn contrast with gasification furnace in commercial processpyrolysis combustion and gasification properties of pulver-ized bituminous coal were investigated at high temperatureof 1400∘C by TG-DTA measurements On the other handtemperature gradient was set up from 20 to 40∘Csdotminminus1 inorder to discuss gasification and combustion ratio of coalconversion In addition Lu et al and Xie et al presentedthat the critical O

2concentration of oxidation combustion

at low temperature is around 5ndash10 [21 22] furthermore

Journal of Combustion 3

5 mm in diameter

25 m

m in

hei

ght

Figure 2 Coal sample in platinum container (asymp30mg coal)

Table 1 Analysis values of coal (air dried basis)

Proximate analysis Weight ()Ash 1270Moisture 242Fixed carbon 5449Volatile matter 3039

high temperature combustionwith low oxygen concentration(le5) is regard as a new generation of high temperatureair combustion technology [23] In other words even if O

2

is controlled as very low concentration (le5) in the flowprovided to coal sample accumulated O

2gas amount is

mostly enough to complete oxidation combustion during theheating process Consequently CO

2-rich atmosphere in the

experiment was controlled by changing O2concentration

from 0 to 5 After that the flue gas generated from theheated coal such as CO CO

2 O2 and HCs were analyzed

in the combustion and gasification processTheweight reduction ratio after themeasurements119909 ()

of coal samples was measured against O2 with increasing

temperature in the atmospheric pressure In addition sameexperiments and flue gas analyses were conducted for pul-verized char samples in the CO

2-rich atmosphere to compare

with the measurement results of coal samples

2 Analytical Approach andExperimental Conditions

21 Coal and Char Samples Coal samples used for theexper-iments were taken from the 8103 face of Tashancolliery in Shanxi province China The properties of whichwere summarized in Table 1 The samples were crushed intoparticles 025 to 05mm in diameter and dried in a vacuumdesiccatorThe volume of crushed coal particles was less thanthat of the platinum container placed in TG-DTA which isalmost equal to 491mm3 as shown in Figure 2

Sample weight placed was about 30mg and its porositywas evaluated as 37 In order to compare coal and charchar samples were made from the same coal samples byheating for 7 minutes in a sealing volatile matter crucible atthe temperature of (900 plusmn 10)∘C based on ISO 5621998 forhard coal and coke determination of the volatile matter Inthe same manner the char particles placed in the containerwere adjusted into the same diameter range of coal

22 Reaction Mechanism As reported by Luo and Zhou [24]and Huang et al [25] the processes of coal combustion andgasification are expressed by the following reactions

(a) Combustion Reaction

C +O2 997888rarr CO2 (1)

C + 1

2

O2997888rarr CO (2)

(b) Gasification Reaction

C + CO2 997888rarr 2CO (3)

C +H2O 997888rarr CO +H2 (4)

C + 2H2 997888rarr CH4 (5)

Reaction equations (1) and (2) are exothermic processesand reaction equations (3) to (5) are endothermic processesCarbon in char matrix reacts with oxygen to form CO andCO2 However it still has not been unified which of them is

the favoured product In general the proportion of COCO2

in products increases gradually with increasing temperatureThus CO is the main product when the reaction temperatureis over around 1030∘C and other parameters are constant [26]

23 Experimental Apparatus and Procedure The thermalanalysis system from 20 to 1400∘C in temperature (TG-DTA) used for the present experiments is shown in Figure 3The thermogravimetric (TG) analyzes sample mass underchanging temperature or elapsed time at a temperatureprogram Differential thermal analysis (DTA) measures thetemperature difference between the analyzed sample and areference material (a substance with no thermal effect in themeasured temperature range such as Al

2O3 as shown in

Figure 3(b)) at a sample temperature TG curves of samplesreflect the relationship between changes in the sample masstemperature and ambient gas Injected gas species gas flowrate and heating rate are shown in Table 2 The flue gasgenerated from the heated coal such as CO CO

2 O2 and

HCs were analyzed by an emission gas analytical systemand a gas chromatography system in the combustion andgasification process

24 Definition of Weight Loss Ratio on TG Curves Thermo-gravimetric analysis is an established method to study coaloxidation reactions Based on the fundamental principle ofchemical dynamics we set the reaction model as 119891(119909) inwhich 119909 is the reaction conversion rate of coal weight loss

119909 =

119898 minus 119898

0

119898

0

(6)

where1198980is the initial samplemass inmg and119898 is the sample

mass in mg at elapsed time 119905 in minThe TG output showing the ratio of coal sample to

reference material (Al2O3) needs to be adjusted before

commencement of TG-DTA experiments The empty weight


(a) Photo of experimental apparatus by using TG-DTA

Heating from furnace (heating rate

Flow gas

Flue gas

Sample

Balance

Gas bomb Gas analyzer

Gas controller

20sim40∘Cmiddotminminus1)

(95sim100 CO2)

Al2O3

(b) Sketch map of TG heating vessel

Figure 3 Schematic diagram of experimental apparatus

Table 2 Experimental conditions of temperatures and gas flow ratesfor the TG-DTA analysis

Sample Gas injected to system Flow rates(mLminminus1)

Heating rates120582 (∘Cminminus1)

Coal

Air 200 2095 CO2 + 5 O2 100sim200 20sim4096 CO2 + 4 O2 100 2097 CO2 + 3 O2 100 2098 CO2 + 2 O2 100 2099 CO2 + 1 O2 100 20

100 CO2 100sim200 20sim40

Char

Air 100 2095 CO2 + 5 O2 100 2096 CO2 + 4 O2 100 2097 CO2 + 3 O2 100 2098 CO2 + 2 O2 100 2099 CO2 + 1 O2 100sim200 20sim40

100 CO2 100 20

of a platinum cup for the coal sample was calibratedmanuallyto 0 when the output was stable

Temperature (Θ) was set with a linear gradient againsttime 119905 in the measurements

Θ = Θ

0+ 120582119905 (7)

where Θ is the cell temperature in ∘C Θ0is the initial

temperature in ∘C and 120582 is the temperature gradient in∘Csdotminminus1

25 Conversion Factor for Heat Generation from DTA OutputAt low temperatures less than 200∘C water evaporated fromcoal sample and sample mass 119898 reduced from the initialmass 119898

0(119898 le 119898

0 ie 119909 le 0) as shown in Figure 4

According to the DTA principle the DTA voltage output

119876

lowast(120583119881) is proportional to heat generation rate per unitmass

119902 (Jsdotminminus1sdotmgminus1) as the following

119902 = 120573

119876

lowast

119898

0

(8)

where 120573 is a conversion factor from 120583119881 to Jsdotminminus1 Heat ofthe Datong coal combustion was previouslymeasured as119867 =

30300 kJsdotkgminus1 = 303 Jsdotmgminus1 Since the DTA curve reached aconstant value after 40min heating heat of coal combustionwas expressed by integrated DTA output from 0 to 40minusing the following

119867 = int

infin

0

119902 (119905) 119889119905 =

120573

119898

0

int

40

0

119876

lowast(119905) 119889119905 =

120573

119898

0

40

sum

119894=0

119876

lowast

119894sdot Δ119905 (9)

where Δ119905 (=1min in present experiments) is interval timeof the DTA output The relationship between cumulativeheat from time 0 to 119905 and 119905 is shown in Figure 4 with TGcurve (119909-119905) The conversion factor was calculated as 120573 =

017 Jsdotminminus1 sdot 120583Vminus1 from the value of119867 at 40min

3 TG-DTA Analyses of Coal Combustionand Gasification

31 Effects of O2Concentration and Gas Flow Rate on Coal

Reaction In the experiments the termination temperaturewas set to 1400∘C with a temperature gradient of 120582 =

20

∘Csdotminminus1 in order to reduce the unburned carbon contentThe injected gas species gas flow rate and heating rate areshown in Table 2

According to the coal TG curves by injecting air (seeFigure 5) the processes of pyrolysis combustion and gasifi-cation of coal in flow air can be divided into three temperaturestages (temperature value is coal body temperature)

(1) 25 to 108∘C calefactive-evaporated-alleviative pro-cess

(2) 108 to 276∘C calefactive-adsorption-weight incre-mental process (O

2absorption)


0

Time (min)

020406080100120140160180200

minus1minus09minus08minus07minus06minus05minus04minus03minus02minus01

0 10 20 30 40

119909(m

gmiddotm

gminus1)

sum119876lowast 119894119872

(120583Vmiddotm

inmiddotm

gminus1)

C 200 mLmiddotminminus1 20∘Cmiddotminminus1)-DTAAir (1000∘C 200 mLmiddotminminus1 20∘Cmiddotminminus1)-TGAir (1000∘

Figure 4 A typical TG-DTA curve of coal combustion in air(Air flow 200mLsdotminminus1 max temperature 1000∘C heating rate20∘Csdotminminus1)

0 10 20 30 40 50 60 70 800

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Time (min)

Tem

pera

ture

(∘C)

CO2 (200 mLmiddotminminus1)CO2 (100 mLmiddotminminus1)Air (100 mLmiddotminminus1) Temperature (∘C) C 20∘Cmiddotminminus11400∘

(200 mLmiddotminminus1)CO2 + 5 O2


Figure 5 TG curves of different gas flow rates and O2concentra-

tions in flow gas

(3) Over 276∘C calefactive-oxidation and combustion-alleviative process [27]

However the processes of coal in the CO2-rich atmo-

sphere can be divided into four temperature stages


(2) 108 to 276∘C calefactive-adsorption-weight incre-mental process (CO

2absorption)

(3) 276 to 650∘C calefactive-devolatilization-alleviativeprocess (refer to volatile matter)

(4) Over 650∘C calefactive-char formation and gasifi-cation-alleviative process

TG results in the CO2-rich atmosphere with different

gas flow rates and O2concentrations are shown in Figure 5

When atmospheric temperature is higher than 360∘C (atgt360∘C the impact of volatile loss onmass is negligible) coalmass reduces with increasing coal body temperature with a

0

03

06

09

12

15

18

21

0 10 20 30 40 50 60 70 80Time (min)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)

119902(Jmiddotm

inminus1middotm

gminus1)

CO2 (200 mLmiddotminminus1)CO2 (100 mLmiddotminminus1)Air (100 mLmiddotminminus1)



Temperature (∘C) C 20∘Cmiddotminminus11400∘

Figure 6 DTA curves of different gas flow rates and O2concentra-

tions in flow gas

linear line especially in air coal conversion was completedwhen atmospheric temperature reached 800∘C In the CO

2-

rich atmosphere the coal burning rate for 95 CO2+ 5 O

2

gas mixture is faster and its conversion time is shorter thanthat of injected 100 CO

2gas On the other hand for the

case of 95 CO2+ 5 O

2 the coal burning rate increases by

increasing gas flow rate from 100mLsdotminminus1 to 200mLsdotminminus1because provided O

2amount increases in unit of time and

its reaction time decreases These phenomenons suggest thatO2amount is the main working factor for coal conversion

rate under the same condition However for the case of 100CO2 the coal burning rate decreases by increasing gas flow

rate from 100mLsdotminminus1 to 200mLsdotminminus1 when atmospherictemperature is lower than 1100∘C It can be assumed thatincreasing CO

2gas flow rate (amount in unit of time) makes

the flame propagation speed and the flame stability declineHowever when atmospheric temperature reached 1100∘Cthe effects of gas flow rate on coal conversion disappearedbecause CO

2gas participated in coal gasification reactions

The phenomenon suggests that CO2gas substitutes the role of

O2gas to improve and stimulate coal conversion in the higher

temperature range from 1100 to 1400∘CAs shown in Figure 6 the heat generation rate of coal is

the highest by providing air flowThis is due to coal oxidationand combustion being an exothermic process on the con-trary the reaction between coal and CO

2is an endothermic

process (refer to Section 22) Moreover flame stability andcoal temperature in CO

2gas-rich flow are lower than those in

air flow environment Additionally when vessel temperatureis lower than 1300∘C the heat generation rate of coal in flowgas of 95 CO

2+ 5 O

2is larger than that of 100 CO

2

However the one of a larger flow rate (200mLsdotminminus1) of 100CO2gas got the highest heat generation after the temperature

reached 1300∘C (see Figure 6) In other words even if 100CO2gas was provided the heat was generated by complex

gasification reactions between coal and CO2gas including

a small amount of H2O in the high-temperature range In

addition a dip and a peak come out on the DTA curve ofthe 100 CO

2gas The minimum point of the dip appears


0 5 10 15 20 25 30 35 40 45 50Time (min)

0


119909(m

gmiddotm

gminus1)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)

Temperature (∘C) 1400 C 40∘Cmiddotminminus1

CO2 (50 mLmiddotminminus1 40∘Cmiddotminminus1)CO2 (100 mLmiddotminminus1 30∘Cmiddotminminus1)

∘

Temperature (∘C) 1400 C 30∘Cmiddotminminus1∘

(50 mLmiddotminminus1 40∘Cmiddotminminus1)CO2 + 5 O2

(100 mL minminus1 30∘C minminus1)CO2 + 5 O2

Figure 7 TG curves of coal under different temperature gradients

at around 1160∘C and the maximum point of the peak comesforth at around 1300∘C The trough may reflect the knownphenomenon that gasification absorbs heat and generatesa differential thermal drop In other words char residuesgenerated from coal are further converted by the gasificationreaction over 1100∘C It can be assumed that coal gasificationwith CO

2gas mainly occurs in higher temperature range

from 1100 to 1400∘C In addition present results show that thechemical reaction of coal in the 100 CO

2differs from air or

gas flow containingO2over 5Those results suggest that the

flame propagation speed the flame stability and the reactionbetween unburned carbon and gas have been improved in thehigh-temperature range

32 Effect of Temperature Gradient on Coal Reaction In themeasurements the terminal (or maximum) temperaturewas set to 1400∘C with the temperature gradient of 120582 =

30

∘Csdotminminus1 or 40∘Csdotminminus1 and gas flow rate of 100mLsdotminminus1or 50mLsdotminminus1 and TG-DTA measurement results inthe CO

2-rich atmosphere with different gas flow rates

are shown in Figures 7 and 8 Comparing the results ofcoal weight reduction with the previous results shown inFigure 5 the coal weight reduction ratio is not sensitive tothe temperature gradient because it is mainly affected by O

2

concentration and the terminal temperature However coalconversion time shortens and differential thermal peak takesplace in advance and heat generation values increases withincreasing temperature gradient from 20∘Csdotminminus1 to40∘Csdotminminus1 Especially for the case of 95 CO

2+ 5 O

2

as shown in Figures 6 and 8 the troughs of the DTA curveswith temperature gradients of 20∘Csdotminminus1 and 30∘Csdotminminus1are unobvious in higher temperature range however thetrough and the peak of 40∘Csdotminminus1 are very evident Thephenomenon suggests that even if 95 CO

2+ 5 O

2gas

was provided the intensity of gasification reaction instead

0 5 10 15 20 25 30 35 40 45 50Time (min)

0

03

06

09

12

15

18

21

119902(Jmiddotm

inminus1middotm

gminus1)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)



∘




Figure 8 DTA curves of coal under different temperature gradients

of oxidation combustion was enhanced by increasingtemperature gradient from 40∘Csdotminminus1

In addition heat generating rates of coal by injecting 95CO2+ 5 O

2(119902 = 097 Jsdotminminus1sdotmgminus1) and 100 CO

2(119902 =

066 Jsdotminminus1sdotmgminus1) are increased around 50 with increas-ing temperature gradient from 20∘Csdotminminus1 to 30∘Csdotminminus1Furthermore the heat generation for 95 CO

2+ 5 O

2

with temperature gradient of 30∘Csdotminminus1 is higher thanthose of others The value of coal heat generation decreaseswith increasing temperature gradient from 30∘Csdotminminus1 to40∘Csdotminminus1 due to endothermic gasification process Inthe high-temperature range the coal conversion is mainlyimplemented by coal gasification instead of coal combustionand the temperature gradient is an essential parameter forimproving and stimulating coal gasification reactions

33 Effects of O2Concentration on Residual and Differential

Thermal Based on TG-DTA results described the differ-ences of the effects of 100 CO

2and 95 CO

2+ 5

O2gas flow on weight reduction ratio 119909 and differential

thermal of coal and reaction products are relatively promi-nent Therefore to further investigate temperature range ofcoal gasification and the effect of O

2concentration on coal

gasification the TG-DTA measurements of the coal werecarried out by setting different termination temperatures of1000∘C 1200∘C and 1400∘C with injected gases of 0 (100CO2) to 5 in O

2concentration 120582 = 20

∘Csdotminminus1 and gasflow rate of 100mLsdotminminus1 The detailed contents are shownin Table 2

The TG-DTA results indicate that O2 0 to 5 con-

tained in CO2-rich gas flow has relatively strong effect on

coal conversion heat generation and reaction products forthe different termination temperatures as shown in Figures 910 and 11 Coal weight reduction ratio increases with increas-ing O

2concentration in the CO

2-rich atmosphere under

the same conditions moreover heat generation reduceswith increasing CO

2concentration due to intensifying


0 5 10 15 20 25 30 35 40 45 50Time (min)

0

200

400

600

800

10000


119909(m

gmiddotm

gminus1)

100 CO2

Temperature (∘C) C 100 mLmiddotminminus1 20∘Cmiddotminminus11000∘

99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(a) TG curves

0

04

08

12

16

2

0 5 10 15 20 25 30 35 40 45 50Time (min)

0

200

400

600

800

1000

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(b) DTA curves

Figure 9 TG-DTA curves of different O2concentrations with a temperature of 1000∘C

0 10 20 30 40 50 60Time (min)

0


119909(m

gmiddotm

gminus1)

0

200

400

600

800

1000

1200

Tem

pera

ture

(∘C)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(a) TG curves

0 10 20 30 40 50 60Time (min)

0

04

08

12

16

2

0

200

400

600

800

1200

1000

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(b) DTA curves


endothermic gasification reaction between coal and CO2gas

Especially it is clear from theDTA curves that the gasificationreaction of coal with CO

2gas mainly occurs in temperature

range from 1100 to 1300∘C In addition the DTA curvesin Figures 10(b) and 11(b) indicate that the greater theatmospheric CO

2 the larger trough radian of curves in

higher temperature range that is intension of gasificationreaction The phenomenon suggests that coal conversion togases will no longer depend on O

2 in the high-temperature

range due to gasification reactionsResidual or ash that remained in the container was

analyzed by an Energy Dispersive Spectrum (EDS) analyzerafter TG-DTA experiments The photos and EDS images ofresiduals or ashes for different CO

2concentrations are shown

in Figures 12 13 and 14 The results of carbon molecularratios C were investigated by EDS analyzer as shown inFigure 15

The analytic results indicated that carbon molecularratios at 1000∘C before gasification and 1400∘C after gasi-fication do not show strong dependency on O

2 On the

other hand the trend of C against temperature showsthat the greater was the atmospheric O

2 the less residual

value of C was measured in the gasification stage withthe termination temperature of 1200∘C In particular carbonmolecular ratios of 4 and 5 O

2contained in CO

2-rich gas

flow are essentially coincident with those of the terminationtemperature of 1400∘C moreover carbon molecular ratio isnearly constant with gas flow containing O

2over 4 in

other words 4 O2contained in O

2CO2gas flow reaches

to the saturation ratio of coal combustion and gasificationreaction in high-temperature range It can be verified fromthe EDS images of residuals or ashes at terminal temperatureof 1200∘C that coal particle surfaces generated many poresin the 100 CO

2gas flow due to coal gasification with CO

2


0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Tem

pera

ture

(∘C)

100 CO2


97 CO2 + 3 O2

95 CO2 + 5 O2

(a) TG curves

0

04

08

12

16

2

0 10 20 30 40 50 60 70Time (min)

119902(Jmiddotm

inminus1middotm

gminus1)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)

100 CO2


97 CO2 + 3 O2

95 CO2 + 5 O2

(b) DTA curves


95 CO 96 CO 97 CO

98 CO 99 CO 100 CO

2 2 2

2 2 2

(a) Photos of residuals

97 CO2 100 CO295 CO2

(b) EDS images of residuals or ashes

Figure 12 Photos of residuals at various CO2concentrations with a

temperature of 1400∘C

gas On the other hand the difference of carbon molecularratio with the terminal temperature of 1200∘C is large from0 to 3 O

2 It can be assumed that coal combustion to

gases is not sufficient with reaction (2) instead of (1) afterthe temperature reached 1100∘C furthermore O

2amount in

unit of time is insufficient for coal conversion within limitedheating time On the other hand the heat provided by theterminal temperature of 1200∘C is not enough to complete

95 CO 96 CO 97 CO2 2 2

98 CO2 99 CO2 100 CO2

(a) photos of residuals

97 CO2 100 CO295 CO2




coal gasification with CO2gasTherefore O

2concentration is

the key factor for coal conversion to gases with the terminaltemperature of 1200∘C However for the case of terminaltemperature of 1400∘C coal conversion to gases is completedit is clear from the photos that residuals form molten state asshown in Figure 12(a) because themelting point of coal ash isaround 1250∘C In addition as shown in Figure 11 the value ofTG-DTA curve with 95 CO

2+ 5O

2gas flow was constant


95 CO 96 CO 97 CO2 2 2

98 CO2 99 CO2 100 CO2


97 CO2 100 CO295 CO2




0 1 2 3 4 5 60

15

30

45

60

75

90

Resid

ual c

arbo

n m

olec

ular

ratio

()

O2 concentration ()

1200∘C

1000∘C

1400∘C

Figure 15 EDS analysis of residual carbon molecular ratios againstO2 in CO

2-rich gas flow

after the temperature reached 1200∘C however the ones of 0and 3 O

2contained in CO

2-rich gas flow came to constant

when the temperature reached 1300∘C Consequently coalconversion to gasesmay break away fromO

2gas and promote

CO2reduction reactions when atmospheric temperature is

over 1300∘C

34 Coal Weight Loss Rate versus Temperature As shown inFigure 16(a) the relationship between coal weight loss rate

(equal to conversion rate of coal to gasses) and temperaturecan be expressed by the following Arrhenius formula

Δ119881

119898

Δ119905

= 119860

0sdot exp (minus 119864

119877119879

)

Δ119881

119898=

119898

0minus 119898

119898

0

(10)

where Δ119881119898Δ119905 is the average rate of coal weight loss at unit

time in 119904minus1 1198980is the initial coal mass in mg 119898 is the coal

mass at elapsed time Δ119905 in mg 119877 (=8314 JsdotKminus1) is the gasconstant 119879(119870) is the absolute temperature 119860

0(119904

minus1) is the

pre-exponential factor and 119864 (kJsdotmolminus1) is the activationenergy

The measurement results indicate that pre-exponentialfactor is almost constant however activation energy ismainlydependency of O

2concentration as shown in Figure 16(b)

moreover it decreased gradually with increasing O2con-

centration Consequently the Arrhenius equation can beexpressed as the following

Δ119881

119898

Δ119905

= 000045 sdot exp(minusminus096119884O2119878 + 13593

119877119879

) (11)

where119884O2119878 is the O2 concentration at surface of coal particlein mole fraction

35 Coal Conversion and Heat Generation Rates Pyrolysiscombustion and gasification of coal can be clarified fromthree peaks generated by analyzing time differential values ofcoal mass denoted by

119889119909

119889119905

=

119889 [(119898 minus 119898

0) 119898

0]

119889119905

(12)

As shown in Figure 17 the range of 20 to 230∘C isdominated by evaporation processes The value of 119889119909119889119905decreases gradually at temperature range from 230 to 360∘Cand becomes near to zero The process corresponds to gasadsorption onto coal internal surface pores after releasingmoisture Volatile matter and HCs gases separate out fromcoal matrix in 360 to 650∘C and the porous chars form in650 to 900∘C In the temperature range of 900 to 1400∘C the119889119909119889119905 shows large values due to gasification and combustionreactions of chars in the CO

2rich gas flow containing a small

percentage of O2

Heat generation rates in unit of coal mass against time119905 or vessel temperature denoted by 119904 = 119902119889119909119889119905 (Jsdotmgminus1)are shown in Figure 18 Heat generation rate of coal can beclassified into four stages based on changes with temperature

(1) 20 to 230∘C coal drying by water evaporation(2) 230 to 360∘C O

2and CO

2gases adsorption before

oxidation and combustion The value of 119904 jumpsdramatically since its mass change is small againstheat generation

(3) 360 to 1100∘C coal oxidation and combustion Maxi-mumpeaks of heat generation rate in unit of coalmassare observed but the value of 119904 reduces gradually withthe formation of porous chars


0 00005 0001 00015 0002 00025 0003 00035

Air

minus750

minus800

minus850

minus900

minus950

minus1000

minus1050

ln(Δ

119881119898Δ

119905) (s

minus1)

119879minus1 (Kminus1)

C 100 mLmiddotminminus1 20∘Cmiddotminminus1

100 CO2

1400∘

95 CO2 + 5 O2

(a) Arrhenius plots of coal weight loss rate versus Tminus1

0

00002

00004

00006

00008

0001

0 5 10 15 20 250

30

60

90

120

150Activation energy (119864)

Pre-exponential factor (1198600)


119864(k

Jmiddotmol

minus1)

O2 concentration (119884

1400∘

1198600

(sminus1)

)O2 S

(b) The effects of O2 concentration on A0 and E

Figure 16 Coal weight loss rates with different temperatures and O2concentrations

000

001

002

003

004

005

006

007

008

0 200 400 600 800 1000 1200 1400Temperature (∘C)

CO2 C 200 mLmiddotmin minus1 20∘Cmiddotmin minus1)CO2 C 100 mLmiddotminminus1 20∘Cmiddotminminus1)CO2 C 100 mLmiddotminminus1 30∘Cmiddotminminus1)

(1400∘

(1400∘(1400∘

(mgmiddot

min

minus1middotm

gminus1)

minus119889119898119889119905119872

C 100 mL(1400∘CO2 + 5 O2 middotminminus1 20∘Cmiddotminminus1)C 200 mL(1400∘CO2 + 5 O2 middotminminus1 20∘Cmiddotminminus1)

C 100 mL(1400∘CO2 + 5 O2 middotminminus1 30∘Cmiddotminminus1)

Figure 17 Coal conversion rate versus atmospheric temperature

(4) 1100 to 1300∘C coal gasification with the reactionbetween residual carbon and CO

2gas

4 Comparisons of Coal and Char

In view of coal properties of oxidation combustion andgasification in the CO

2-rich atmosphere comparisons of

TG-DTA results of coal and char were also conducted byproviding the CO

2-rich gas flow The contents of experi-

mental temperature and ambient gas are shown in Table 2In addition during the experiments flue gases generatedfrom the heated coal or char particles were simultaneouslyanalyzed by the gas analytical system transferred from TG-DTA using an air pump (100mLsdotminminus1) in order to discussthe optimum O

2 in the CO

2-rich gas for coal or char

combustion and gasificationGases ofO2 HCs andCO in the

CO2-rich gas were measured with a time interval of 1 second

by the gas analytical system

0255075

100125150175200225250

0 200 400 600 800 1000 1200 1400Temperature (degC)

(Jmiddotm

gminus1)

minus119902119889119909119889119905


(1400∘

(1400∘(1400∘



Figure 18 Heat generation rate versus atmospheric temperature

41 Comparisons of TG-DTA Curves In the TG-DTA mea-surements the termination temperature was set to 1400∘Cwith a temperature gradient of 120582 = 20∘Csdotminminus1 and ambientgas was supplied by 100 CO

2or 95 CO

2+ 5 O

2gas

with gas flow rate of 100mLsdotminminus1 Sample mass used in theexperiments was around 30mg (see Figure 2)

The TG-DTAmeasurement results of coal and char in theCO2-rich gas flow are shown in Figures 19 and 20 Difference

of conversion rate between coal and char is obvious withwater and volatile matter evaporations in the initial stage of20 to 230∘C as shown in Figure 19 The water and volatilematter separate out from coal particles but there is no changefor char during the period After that the stage transfers tothe next common stage of forming porous matrix Coal orchar gasification stage is verified at 1100∘C by char mass lossin 100 CO

2atmosphere (see Figure 19) In addition heat

generation rate of char in 95 CO2+ 5 O

2gas flow is

higher than those in other gas flows as shown in Figure 20It can be assumed that 5 O

2in the CO

2-rich gas flow was


0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Tem

pera

ture

(∘C)

Temperature (∘C)100 CO2 coal100 CO2 char

TG-DTA (1400∘C 100 mLmiddotminminus1 20∘Cmiddotminminus1)

char95 CO2 + 5 O2

coal95 CO2 + 5 O2

Figure 19 TG comparisons of coal and char in the CO2-rich

atmosphere

00

02

04

06

08

10

12

14

0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

1400

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)



char95 CO2 + 5 O2

coal95 CO2 + 5 O2

Figure 20 DTA comparisons of coal and char in the CO2-rich

atmosphere

sufficient to complete char combustion On the other handheat generation of char gasification in 100 CO

2gas flow is

larger than that of coal the measurement result suggests thatthe heat of adsorption with char gasification in the gas flow issmaller than that of coal because of heat consumption fromevaporation of volatile matter in coal and the formation ofporous chars

42 Gas Generation from Coal or Char by Various O2Con-

centrations In the TG-DTA heating process the flue gasesgenerated from the heated coal such as CO and HCs gaseshave been analyzed by the emission gas analytical systemHCs gas amount generated from coal was measured by pro-viding gas flow with various O

2 As shown in Figure 21 the

gases were generated from coal samples in the temperaturerange from 400 to 650∘C In the case of char there is no HCsgas generation in the same condition It can be determinedthat HCs gas is formed with the moisture or volatile matterof coal In addition HCs generation rate in air is lower thanthose of other gases furthermore HCs generation from coal

0

10

20

30

40

50

60

70

HCs

(ppm

)

0 100 200 300 400 500 600 700Temperature (∘C)

100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air

TG-DTA (1400∘C 100 mL 20∘Cmiddotminminus1) coalmiddotminminus1

Figure 21 HCs gas generation from coal in air and CO2-rich gas

flows

in 100 CO2is evaluated as roughly 12mLsdotgminus1-coal that

is higher than those of other gases containing O2 In other

words under the same condition lowO2 can promote HCs

generation in the CO2-rich gas flow

Figures 22 and 23 show CO gas generation from theheated coal or char in air or CO

2-rich gas flow In the case

of coal in air flow CO gas concentration is less than 500 ppmat temperature lower than 700∘C On the other hand CO gasgeneration from coal in 100 CO

2gas flow at temperature

over 900∘C is roughly 235mLsdotgminus1-coal that is the largestamong the CO

2-rich gas flows although the maximum

peak concentration is recorded in 99 CO2+ 1 O

2gas

flow Moreover the peak time of CO concentration matchesthe trough bottom of DTA heat generation curves (referto Figures 18 and 20) which correctly verifies endothermicprocesses of coal gasification It is intuitively confirmed byCO generation area with increasing temperature from 900 to1400∘C as shown in Figure 22

Additionally CO generation amount of coal graduallydecreases with increasing O

2concentration from 0 to 5

in the CO2-rich gas Furthermore CO generation concen-

trations from coal for 4 and 5 O2contained in CO

2-

rich gas flow arealmost lower than 300 ppm in TG-DTAheating process which are smaller than that in air flow Themeasurement results suggest that the optimum CO

2-rich

gas flow for coal gasification and combustion is evaluatedwith 96 CO

2+ 4 O

2gas from the present TG-DTA

experiments The analytical result exactly matches the EDSanalysis of Section 33 Moreover it can be assumed that COgeneration from coal in air partly formed by reaction (2)however rich CO

2gas inhibited coal conversion to gases in

the temperature range from 20 to 600∘COn the other hand CO generation concentrations from

char for 2 to 5 O2contained in CO

2-rich gas flow areap-

proximately lower than 300 ppm in TG-DTAheating processMoreover nothing but CO gas generation in 99 CO

2+ 1

O2gas flow is obvious in the CO

2-rich gas flow Therefore


0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air

Figure 22 CO gas generation of coal in air and CO2-rich gas flows

0

2000

4000

6000

8000

10000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)

TG-DTA charminus1 ∘ minus1(1400∘C 100 mLmiddotmin 20 Cmiddotmin )

100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air

Figure 23 CO gas generation of char in air and CO2-rich gas flows

the optimum CO2-rich gas flow for char gasification and

combustion is evaluated with 98 CO2+ 2 O

2gas flow as

shown in Figure 23 Similarly CO generation amount fromchar samples in 100 CO

2gas is roughly 460mLsdotgminus1-char

that is also higher than those of other gases Comparing theresults of coal and char samples in 100 CO

2gas flow CO

gas generation amount of char samples is higher than that ofcoal samples because the volatile matter of coal participatesin carbon gasification with CO

2gas and decreases CO gas

generation

43 Effects of Temperature Gradient and FlowRate on Flue GasGeneration Themeasurement results of flue gases generatedfrom coal samples in 100 CO

2gas with different gas flow

rates and temperature gradients set to TG-DTA are shownin Figures 24 and 25 In the measurements of coal samples

0

20

40

60

80

100

120

0 100 200 300 400 500 600 700

HCs

(ppm

)

Temperature (∘ C)

TG-DTA coal 100 CO2

minus1 ∘ minus11400

∘C 100 mLmiddotmin 20 Cmiddotminminus1 ∘ minus1

1400∘C 200 mLmiddotmin 20 Cmiddotmin


∘C 200 mLmiddotmin 40 Cmiddotmin

Figure 24 HCs gas generation of coal with different temperaturegradients and gas flow rates

0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)

TG-DTA coal 100 CO2






Figure 25 CO gas generation of coal with different temperaturegradients and gas flow rates

the termination temperature was set to 1400∘C Both of COand HCs gases generations are not sensitive to the gas flowrate because it is mainly controlled by O

2 and temperature

range However HCs gas generation becomes approximatelydouble by increasing temperature gradient from 20∘Csdotminminus1to 40∘Csdotminminus1 Furthermore CO gas generation amount alsoincreases with increasing temperature gradient and the peakextent of CO gas concentration is extended against tem-perature These measurement results suggest that high tem-perature gradient accelerates coal gasification and stimulatesgasified gases generation On the contrary low temperaturegradient promotes slow oxidation of coal and gas generationof CO

2

In the measurements of char samples the terminationtemperature was set to 1400∘C with a temperature gradientof 20∘Csdotminminus1 and 40∘Csdotminminus1 ambient gas was suppliedby injected 99 CO

2+ 1 O

2gas with gas flow rate of

50mLsdotminminus1 and 100mLsdotminminus1 As shown in Figure 26 CO


0

1500

3000

4500

6000

7500

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)

TG-DTA char 1 O2 + 99 CO2






Figure 26 CO gas generation from char in 99 CO2+ 1 O

2gas

flow with different temperature gradients and gas flow rates

50

60

70

80

90

100

0 10 20 30 40 50 60

Coa

l wei

ght r

educ

tion

ratio

() TG-DTA 1400∘C 100 mLmiddotminminus1

Coal 95 CO2 + 5 O2 Char 95 CO2 + 5 O2

Coal 100 CO2 Char 100 CO2

Temperature gradient (∘Cmiddotminminus1)

Figure 27 Comparisons of weight reduction ratio versus tempera-ture gradient between coal and char

gas generation is not sensitive to gas flow rate howeverthe amount of generating CO gas becomes nearly doubleby increasing temperature gradient from 20∘Csdotminminus1 to40∘Csdotminminus1 In addition one phenomenon occurs in whichtemperature area of CO gas generated from coal with thetemperature gradient of 40∘Csdotminminus1 is almost uniform to thearea of CO generation by the heated char in the CO

2-rich

gas flow under low O2 It shows that the condition of high

temperature gradient in a CO2-rich gas flow with low O

2

is beneficial to coal gasification with O2incomplete com-

bustion and CO2circulation technology further improves

the utilization of CO2gas on coal-fired power generation

technologies

44 Effects of Temperature Gradients on Coal Weight Reduc-tionRatio andGasesGeneration As shown in Figure 27 bothof weight reduction ratios of coal and char decrease with

0

05

10

15

20

25

Cum

ulat

ive H

Cs (m

Lmiddotgminus

1)

0 1 2 3 4 5 6O2 ()

Coal 40∘Cmiddotminminus1


TG-DTA CO2 + O2 1400∘C 100 mLmiddotminminus1

Figure 28 Cumulative HCs gas versus O2 for different tempera-

ture gradients during 20 to 700∘C (0 to 35min)

0

100

200

300

400

500

600

Cum

ulat

ive C

O (m

Lmiddotgminus

1)


0 1 2 3 4 5 6O2 ()


Coal 20∘Cmiddotminminus1Char 40∘Cmiddotminminus1

Char 20∘Cmiddotminminus1

Figure 29 Cumulative COgas versusO2 for different temperature

gradients during 20 to 1400∘C (0 to 70min)

increasing temperature gradient at various O2 in CO

2-rich

gas flow However coal is more sensitive to the temperaturegradient and its weight decreases more than that of charsince volatile matter of coal participates in converting coal togases

In the TG-DTAmeasurements the effects of temperaturegradient on cumulative HCs and CO gases are shown inFigures 28 and 29 The experimental results indicate thatcumulative HCs and CO gases from coal and char areincreased by increasing temperature gradient from 20 to40∘Csdotminminus1 Furthermore the cumulative CO gas volumegenerated from the char is the largest at temperature gradientof 40∘Csdotminminus1 It is clear that the effect of temperaturegradient on HCs and CO gases generations decreases withincreasing O

2 from 0 to 5 O

2 especially for CO gas In

addition cumulative CO gas generated from coal in 99CO2+ 1 O

2gas flow with different temperature gradients

is essentially coincident with that of char It can be assumed


that carbon in volatilematter of coal almost converted to CO2

gasThemeasurement results suggest that O2 is the primary

parameter of coal gasification reactions with low temperaturegradient Consequently the condition of higher temperaturegradient and low O

2 less than 1 makes stimulate and

enhances generations of gasified gases such HCs and CO

5 Conclusions

In this study characteristics of pyrolysis combustion andgasification of Datong coal and char were investigated attemperature range from 20 to 1400∘C with heating temper-ature gradient of 20 to 40∘Csdotminminus1 in a CO

2-rich gas flow

by TG-DTA analyses The TG-DTA results were discussedto make clear the effects of O

2 in CO

2-rich gas and

heating temperature gradient on coal physical and chemicalbehaviors related to coal gasification with CO

2and oxygen

combustion and underground coal gasificationThe main findings are summarized as follows

(1) The processes of coal in CO2-rich gas atmosphere

mainly are divided into two temperature ranges forcoal devolatilization char formation and gasification

(2) Coal mass reduces with increasing coal matrix tem-perature with a linear line at various O

2concentra-

tions that is the main impact factor for coal conver-sion rate at temperature lower than 1100∘CMoreovercoal weight loss against temperature followed theArrhenius equation

(3) There are dip and peak on the DTA curves for 100CO2gas flow The minimum point of the dip appears

at around 1160∘C and the maximum point is ataround 1300∘C Coal gasification in 100 CO

2gas

flow is generated mainly in the temperature rangefrom 1100 to 1300∘C Therefore coal conversion togases may break away from O

2gas and promote CO

2

reduction reactions at temperature over 1300∘C(4) For the case of terminal temperature of 1200∘C the

higher O2 was in CO

2-rich gas flow the less C in

was measured in residuals or ashes(5) HCs gas generated from coal was measured at tem-

perature range from 400 to 650∘C in the CO2-rich gas

flow and it can be formed frommoisture and volatilematter in coal

(6) CO gas generation amount gradually decreases withincreasing O

2 during 0 to 5 in CO

2-rich gas flow

Additionally the peak time on CO gas concentrationor generation matched with the time showing thetrough bottom of heat generation curvesmeasured byDTA

(7) The optimum CO2-rich gas flow for gasification and

combustion reactions of coal and char is evaluatedwith 96 CO

2+ 4 O

2and 98 CO

2+ 2 O

2gas

from the present TG-DTA experiments respectively(8) Temperature gradient per unit time for heating coal

and char samples is a secondary essential parameter toimproving and stimulating coal and char gasification

Coal conversion factor is mainly implemented bycoal gasification instead of coal combustion when thetemperature gradient is over 40∘Csdotminminus1

(9) The higher temperature gradient accelerates coaland char gasification reaction with CO

2gas on the

contrary low temperature gradient promotes coal andchar slow oxidation with low gases generation rate

Acknowledgments

This study was partly supported by the NEDO (P08020)project on Innovative Zero-emissionCoal Gasification PowerGeneration JSPS KAKENHI Grant-in-Aid for ScientificResearch (B) no 25303030 and the cooperative researchproject between Kyushu University and Liaoning TechnicalUniversity on ldquoCO

2geological storage and utilization for

coalrdquo

References

[1] W Zhang and Z Wu ldquoA study on establishing low-carbonauditing system in chinardquo Low Carbon Economy vol 3 no 2pp 35ndash38 2012

[2] S Zeng and S Zhang ldquoLiterature review of carbon finance andlow carbon economy for constructing low carbon society inChinardquo Low Carbon Economy vol 2 no 1 pp 15ndash19 2011

[3] R Lei Y Zhang and SWei ldquoInternational technology spilloverenergy consumption and CO

2emissions in Chinardquo LowCarbon

Economy vol 3 no 3 pp 49ndash53 2012[4] Key World Energy Statistics International Energy Agency

(IEA) ldquoClearly-presented data on the supply transformationand consumption of all major energy sourcesrdquo Stedi Media2010

[5] A Williams M Pourkashanian J M Jones and N SkorupskaCombustion and Gasification of Coal Applied Energy Technol-ogy Series Taylor amp Francis New York NY USA 1999

[6] S Hossain ldquoAn econometric analysis for CO2emissions energy

consumption economic growth foreign trade and urbanizationof Japanrdquo Low Carbon Economy vol 3 no 3 pp 92ndash105 2012

[7] C Ramırez and J Gonzalez ldquoContribution of finance to the lowcarbon economyrdquo LowCarbon Economy vol 2 no 2 pp 62ndash702011

[8] IPCC Working Group II ldquoClimate change 2007 impactsadaptation and vulnerabilityrdquo Assessment Report of the Inter-governmental Panel on Climate Change Cambridge UniversityPress 2007

[9] Key World Energy Statistics International Energy Agency(IEA) ldquoEvolution from 1971 to 2010 of World CO

2emissions

by regionrdquo Stedi Media 2011[10] IEA ldquoCO

2emissions from fuel combustionrdquo 2011 httpwww

ieaorgCO2highlights[11] H Herzog and D Golomb ldquoCarbon capture and storage from

fossil fuel userdquoEncyclopaedia of Energy vol 1 pp 277ndash287 2004[12] K Jordal M Anheden J Y Yan and L Stromberg ldquoOxyfuel

combustion for coal-fired power generation with CO2capture-

opportunities and challengesrdquo Greenhouse Gas Control Tech-nologies 7 vol 1 pp 201ndash209 2005

[13] Office of Fossil Energy ldquoCarbon capture amp separationrdquo US De-partment of Energy 2004 httpfossilenergygovprogramssequestration


[14] J C Chen Z S Liu and J S Huang ldquoEmission characteristicsof coal combustion in different O

2N2 O2CO2and O

2RFG

atmosphererdquo Journal of Hazardous Materials vol 142 no 1-2pp 266ndash271 2007

[15] D Singh E Croiset P L Douglas andMA Douglas ldquoTechno-economic study of CO

2capture from an existing coal-fired

power plant MEA scrubbing versus O2CO2recycle combus-

tionrdquo Energy Conversion and Management vol 44 no 19 pp3073ndash3091 2003

[16] E S Hecht C R Shaddix M Geier A Molina and B SHaynes ldquoEffect of CO

2and steam gasification reactions on

the oxy-combustion of pulverized coal charrdquo Combustion andFlame vol 159 pp 3437ndash3447 2012

[17] B J P Buhre L K Elliott C D Sheng R P Gupta and TF Wall ldquoOxy-fuel combustion technology for coal-fired powergenerationrdquo Progress in Energy and Combustion Science vol 31no 4 pp 283ndash307 2005

[18] Q Li C Zhao X Chen W Wu and Y Li ldquoComparison ofpulverized coal combustion in air and in O

2CO2mixtures by

thermo-gravimetric analysisrdquo Journal of Analytical and AppliedPyrolysis vol 85 no 1-2 pp 521ndash528 2009

[19] H Liu ldquoCombustion of coal chars in O2CO2and O

2N2

mixtures a comparative study with non-isothermal thermo-gravimetric analyzer (TGA) testsrdquo Energy and Fuels vol 23 no9 pp 4278ndash4285 2009

[20] Z H Li X M Zhang Y Sugai J R Wang and K SasakildquoProperties and developments of combustion and gasification ofcoal and char in a CO

2-rich and recycled flue gases atmosphere

by rapid heatingrdquo Journal of Combustion vol 2012 Article ID241587 11 pages 2012

[21] P Lu G X Liao J H Sun and P D Li ldquoExperimental researchon index gas of the coal spontaneous at low-temperature stagerdquoJournal of Loss Prevention in the Process Industries vol 17 no 3pp 243ndash247 2004

[22] J Xie W M Cheng and F Q Liu ldquoTechnology and effect ofopen nitrogen injection at fully mechanized facerdquo Journal ofSafety in Coal Mines vol 3 pp 33ndash35 2007

[23] H Y Qi Y H Li C F You J Yuan and X C Xu ldquoEmissionon NO

119909in high temperature combustion with low oxygen

concentrationrdquo Journal of Combustion Science and Technologyvol 8 no 1 pp 17ndash22 2002

[24] C X Luo and W H Zhou ldquoCoal gasification technology amp itsapplicationrdquo Sino-Global Energy vol 1 pp 28ndash35 2009

[25] J J Huang Y T Fang and Y Wang ldquoDevelopment andprogress ofmodern coal gasification technologyrdquo Journal of FuelChemistry and Technology vol 30 no 5 pp 385ndash391 2002

[26] Y F Liu and X K Xue ldquoThermal calculation methods for oxy-fuel combustion boilersrdquo East China Electric Power vol 36 pp355ndash357 2008

[27] J R Wang C B Deng Y F Shan L Hong andW D Lu ldquoNewclassifying method of the spontaneous combustion tendencyrdquoJournal of the China Coal Society vol 33 no 1 pp 47ndash50 2008

International Journal of

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Shock and Vibration


Civil EngineeringAdvances in

Acoustics and VibrationAdvances in



Electrical and Computer Engineering

Journal of

Advances inOptoElectronics


Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

SensorsJournal of


Modelling amp Simulation in EngineeringHindawi Publishing Corporation httpwwwhindawicom Volume 2014


Chemical EngineeringInternational Journal of Antennas and

Propagation




Navigation and Observation



DistributedSensor Networks



Gasification and combustion

(power and heat)

Coalchar

Postcombustion capture

Coalchar

Precombustion capture

Steam


(oxidoeduction) Power and heat


(oxidoreduction)

Coalchar

Coal added steam for enhancing gasification reactions

O2

O2

O2

N2

CO2 and steam

CO2 and NO119909

H2 CO CO2

High CO2

High CO2

H2 CO HCs CO2

CO2 and H2O recirculating

New O2CO2 oxy-fuelcombustion capture

Power and heat

Figure 1 Schematic diagram of three kinds of power generationwith CO

2capture

about 526 of total CO2emission in China International

Energy Agency (IEA) predicted that in 2030 China wouldemit twice as much carbon dioxide as that in 2007 providedthat CO

2emissions increase by 29 each year [10]

As stationary sources emitting large amounts of CO2

pulverized coal fired power plants could be the best candi-dates to install CO

2capture system which can be classified

into three categories in general precombustion capturepostcombustion capture and oxy-fuel strategy as shown inFigure 1 [11 12] The traditional coal fired boilers use air forcombustion in which N

2gas is 79 in volume ratio Its flue

gas includes only about 15 CO2 therefore the CO

2capture

efficiency by post-combustion system is not high [13 14]Furthermore CO

2capture cost from the flue gas using amine

scrubbing is expected to be relatively high [15] In the case ofpre-combustion capture although calorific value of oxy-firedcoal boiler is higher than that of air-fired coal boiler there is amajor disadvantage for oxygen-blown gasifier that is to buildan oxygen plant In general an oxygen plant consumes about5 of the gross power generated which is the main reasonwhy the total of plant investment for an oxygen-blown plantis somewhat higher than that of an air-blown plant [5]

As an alternative a zero-emission power plant of pul-verized coal-fired power generation in a nitrogen-free atmo-sphere most known as oxy-fuel or O

2CO2combustion tech-

nology for pre-combustion capture is one of new promisingmethods to approach the problem of CO

2separation and

capture In this technology CO2gas substitutes the role

of O2gas to improve and stimulate coal conversion and

reduce O2consumption Recently coal gasification with CO

2

and oxygen combustion technology has been investigatedfor next coal fired power [16 17] In addition this typeof pulverized coal fired power plant is mainly composedof gasifier and combustor as shown in Figure 1 Moreovergasification process of pulverized coal in the gasifier is thecore part of the technology because it determines synthesisgas product and thermal efficiency This process is also the

focus of the research in this paper moreover it has beenverified that the processes of coal in CO

2-rich gas atmosphere

mainly are divided into two temperature ranges for coaldevolatilization char formation and gasification

The implementation of these improved combustion tech-nologies for replacing N

2with CO

2in feeding gas requires

further understanding of physical and chemical characteris-tics in the process of oxidation combustion and gasificationof coal with gradually increasing temperature in CO

2-rich

atmosphere In particular reaction characteristics of coalgasification in a CO

2-rich atmosphere are required for coal

seam underground coal gasification (UCG) projects Li etal presented the comparisons in TGA experiments withbituminous coal at high temperature of 1000∘C with heatingrate of 10 to 30∘Csdotminminus1 in the mixture of O

2N2or O2CO2

with various oxygen concentrations (21 30 40 and 80) [18]and Liu presented the properties of coal chars prepared fromUK high-volatile bituminous and anthracite coals by usingTGA with heating rate of 25 to 125∘Csdotminminus1 in mixturesof O2CO2and O

2N2with O

2concentrations of 3 6 10

21 and 30 [19] However researchers did not measure fluegas and heat generation by coal combustion and gasificationThe unburned carbon content in CO

2rich atmosphere is

expected to be higher than those in air environment due toO2concentrationAuthors (Li et al 2012) [20] have presented the com-

bustion and gasification properties of Datong coal and charin CO

2-rich gas flow (5 or 10 O

2) by rapid heating with

temperature gradient of 50 to 200∘Csdotsminus1 using a CO2laser

beam In the experiments the coal conversion ratio to gaseswas measured for different coal temperature time gradientwith monitoring of CO and HC gases generated from heatedcoal particles Based on experimental results by the rapidheating of dry moist coal and mixing coal-water samplesit has been clarified that coal moisture (internal water) andexternal water of coal particles have the same function toincrease HC-gas production and decrease CO-gas amountby promoting chemical reactions between carbon or COand H

2O Consequently a possibility has been shown to

accomplish coal gasification in CO2-rich atmosphere includ-

ing enough water vapor to carry out low-cost CO2capture

Most researchers presented the results in TGA experi-ments with coal and char at high temperature however theexperimental results were restricted to HCs and CO gasifiedgases analysis and heat generation after coal gasificationInvestigation of gasification and combustion reactivity ofcoal in CO

2-rich atmosphere at high temperature HCs

CO and so forth gasified gases generations is essential forthe development of gasification technology in the futureIn contrast with gasification furnace in commercial processpyrolysis combustion and gasification properties of pulver-ized bituminous coal were investigated at high temperatureof 1400∘C by TG-DTA measurements On the other handtemperature gradient was set up from 20 to 40∘Csdotminminus1 inorder to discuss gasification and combustion ratio of coalconversion In addition Lu et al and Xie et al presentedthat the critical O

2concentration of oxidation combustion

at low temperature is around 5ndash10 [21 22] furthermore


5 mm in diameter

25 m

m in

hei

ght





2


2gas amount is
















C +O2 997888rarr CO2 (1)

C + 1

2

O2997888rarr CO (2)


C + CO2 997888rarr 2CO (3)

C +H2O 997888rarr CO +H2 (4)

C + 2H2 997888rarr CH4 (5)





2O3 as shown in


2 O2 and



119909 =

119898 minus 119898

0

119898

0

(6)








Flow gas

Flue gas

Sample

Balance


Gas controller


(95sim100 CO2)

Al2O3






Coal


100 CO2 100sim200 20sim40

Char


100 CO2 100 20



Θ = Θ

0+ 120582119905 (7)




0(119898 le 119898



119876



119902 = 120573

119876

lowast

119898

0

(8)



119867 = int

infin

0

119902 (119905) 119889119905 =

120573

119898

0

int

40

0

119876

lowast(119905) 119889119905 =

120573

119898

0

40

sum

119894=0

119876

lowast

119894sdot Δ119905 (9)






20





2absorption)


0

Time (min)

020406080100120140160180200


0 10 20 30 40

119909(m

gmiddotm

gminus1)

sum119876lowast 119894119872

(120583Vmiddotm

inmiddotm

gminus1)



0 10 20 30 40 50 60 70 800

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Time (min)

Tem

pera

ture

(∘C)





tions in flow gas






2absorption)






0

03

06

09

12

15

18

21

0 10 20 30 40 50 60 70 80Time (min)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)

119902(Jmiddotm

inminus1middotm

gminus1)






tions in flow gas


2-


2



case of 95 CO2+ 5 O














2is an endothermic




2+ 5 O


2








0 5 10 15 20 25 30 35 40 45 50Time (min)

0


119909(m

gmiddotm

gminus1)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)



∘












30




2


2+ 5 O

2


2+ 5 O

2gas


0 5 10 15 20 25 30 35 40 45 50Time (min)

0

03

06

09

12

15

18

21

119902(Jmiddotm

inminus1middotm

gminus1)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)



∘








2(119902 =


2+ 5 O

2




2and 95 CO

2+ 5















0 5 10 15 20 25 30 35 40 45 50Time (min)

0

200

400

600

800

10000


119909(m

gmiddotm

gminus1)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(a) TG curves

0

04

08

12

16

2

0 5 10 15 20 25 30 35 40 45 50Time (min)

0

200

400

600

800

1000

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(b) DTA curves


0 10 20 30 40 50 60Time (min)

0


119909(m

gmiddotm

gminus1)

0

200

400

600

800

1000

1200

Tem

pera

ture

(∘C)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(a) TG curves

0 10 20 30 40 50 60Time (min)

0

04

08

12

16

2

0

200

400

600

800

1200

1000

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(b) DTA curves














2 On the


2 the less residual


2contained in CO

2-rich gas


2over 4 in





2


0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Tem

pera

ture

(∘C)

100 CO2


97 CO2 + 3 O2

95 CO2 + 5 O2

(a) TG curves

0

04

08

12

16

2

0 10 20 30 40 50 60 70Time (min)

119902(Jmiddotm

inminus1middotm

gminus1)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)

100 CO2


97 CO2 + 3 O2

95 CO2 + 5 O2

(b) DTA curves


95 CO 96 CO 97 CO

98 CO 99 CO 100 CO

2 2 2

2 2 2


97 CO2 100 CO295 CO2







2amount in


95 CO 96 CO 97 CO2 2 2

98 CO2 99 CO2 100 CO2


97 CO2 100 CO295 CO2





2concentration is


2+ 5O



95 CO 96 CO 97 CO2 2 2

98 CO2 99 CO2 100 CO2


97 CO2 100 CO295 CO2




0 1 2 3 4 5 60

15

30

45

60

75

90

Resid

ual c

arbo

n m

olec

ular

ratio

()

O2 concentration ()

1200∘C

1000∘C

1400∘C


2-rich gas flow


2contained in CO



2gas and promote


over 1300∘C



Δ119881

119898

Δ119905

= 119860


119877119879

)

Δ119881

119898=

119898

0minus 119898

119898

0

(10)




0(119904

minus1) is the






Δ119881

119898

Δ119905


119877119879

) (11)



119889119909

119889119905

=

119889 [(119898 minus 119898

0) 119898

0]

119889119905

(12)



percentage of O2



2and CO





0 00005 0001 00015 0002 00025 0003 00035

Air

minus750

minus800

minus850

minus900

minus950

minus1000

minus1050

ln(Δ

119881119898Δ

119905) (s

minus1)



100 CO2

1400∘

95 CO2 + 5 O2


0

00002

00004

00006

00008

0001

0 5 10 15 20 250

30

60

90

120




119864(k

Jmiddotmol

minus1)


1400∘

1198600

(sminus1)

)O2 S



000

001

002

003

004

005

006

007

008

0 200 400 600 800 1000 1200 1400Temperature (∘C)


(1400∘

(1400∘(1400∘

(mgmiddot

min

minus1middotm

gminus1)

minus119889119898119889119905119872





2gas







2 in the CO





0255075

100125150175200225250


(Jmiddotm

gminus1)

minus119902119889119909119889119905


(1400∘

(1400∘(1400∘





2or 95 CO

2+ 5 O

2gas






2gas flow is


2in the CO

2-rich gas flow was


0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Tem

pera

ture

(∘C)



char95 CO2 + 5 O2

coal95 CO2 + 5 O2


atmosphere

00

02

04

06

08

10

12

14

0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

1400

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)



char95 CO2 + 5 O2

coal95 CO2 + 5 O2


atmosphere


2gas flow is






0

10

20

30

40

50

60

70

HCs

(ppm

)

0 100 200 300 400 500 600 700Temperature (∘C)

100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air



flows












2gas






2-


2-rich


2+ 4 O








2+ 1




0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air


0

2000

4000

6000

8000

10000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air




2gas flow as




2gas flow CO



generation




0

20

40

60

80

100

120

0 100 200 300 400 500 600 700

HCs

(ppm

)

Temperature (∘ C)

TG-DTA coal 100 CO2







0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)

TG-DTA coal 100 CO2








2 and temperature


2


2+ 1 O




0

1500

3000

4500

6000

7500

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)








2gas


50

60

70

80

90

100

0 10 20 30 40 50 60

Coa

l wei

ght r

educ

tion

ratio


Coal 95 CO2 + 5 O2 Char 95 CO2 + 5 O2





2-rich



2




technologies


0

05

10

15

20

25

Cum

ulat

ive H

Cs (m

Lmiddotgminus

1)

0 1 2 3 4 5 6O2 ()






0

100

200

300

400

500

600

Cum

ulat

ive C

O (m

Lmiddotgminus

1)


0 1 2 3 4 5 6O2 ()







2-rich



2 from 0 to 5 O











5 Conclusions


2-rich gas flow


2 in CO

2-rich gas and


2and oxygen





2concentra-




2gas


2gas and promote CO

2


higher O2 was in CO







2-rich gas flow




2+ 4 O

2and 98 CO

2+ 2 O

2gas





2gas on the


Acknowledgments



coalrdquo

References













2emissions










2N2 O2CO2and O

2RFG











2CO2mixtures by



2N2
















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










5 mm in diameter

25 m

m in

hei

ght





2


2gas amount is
















C +O2 997888rarr CO2 (1)

C + 1

2

O2997888rarr CO (2)


C + CO2 997888rarr 2CO (3)

C +H2O 997888rarr CO +H2 (4)

C + 2H2 997888rarr CH4 (5)





2O3 as shown in


2 O2 and



119909 =

119898 minus 119898

0

119898

0

(6)








Flow gas

Flue gas

Sample

Balance


Gas controller


(95sim100 CO2)

Al2O3






Coal


100 CO2 100sim200 20sim40

Char


100 CO2 100 20



Θ = Θ

0+ 120582119905 (7)




0(119898 le 119898



119876



119902 = 120573

119876

lowast

119898

0

(8)



119867 = int

infin

0

119902 (119905) 119889119905 =

120573

119898

0

int

40

0

119876

lowast(119905) 119889119905 =

120573

119898

0

40

sum

119894=0

119876

lowast

119894sdot Δ119905 (9)






20





2absorption)


0

Time (min)

020406080100120140160180200


0 10 20 30 40

119909(m

gmiddotm

gminus1)

sum119876lowast 119894119872

(120583Vmiddotm

inmiddotm

gminus1)



0 10 20 30 40 50 60 70 800

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Time (min)

Tem

pera

ture

(∘C)





tions in flow gas






2absorption)






0

03

06

09

12

15

18

21

0 10 20 30 40 50 60 70 80Time (min)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)

119902(Jmiddotm

inminus1middotm

gminus1)






tions in flow gas


2-


2



case of 95 CO2+ 5 O














2is an endothermic




2+ 5 O


2








0 5 10 15 20 25 30 35 40 45 50Time (min)

0


119909(m

gmiddotm

gminus1)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)



∘












30




2


2+ 5 O

2


2+ 5 O

2gas


0 5 10 15 20 25 30 35 40 45 50Time (min)

0

03

06

09

12

15

18

21

119902(Jmiddotm

inminus1middotm

gminus1)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)



∘








2(119902 =


2+ 5 O

2




2and 95 CO

2+ 5















0 5 10 15 20 25 30 35 40 45 50Time (min)

0

200

400

600

800

10000


119909(m

gmiddotm

gminus1)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(a) TG curves

0

04

08

12

16

2

0 5 10 15 20 25 30 35 40 45 50Time (min)

0

200

400

600

800

1000

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(b) DTA curves


0 10 20 30 40 50 60Time (min)

0


119909(m

gmiddotm

gminus1)

0

200

400

600

800

1000

1200

Tem

pera

ture

(∘C)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(a) TG curves

0 10 20 30 40 50 60Time (min)

0

04

08

12

16

2

0

200

400

600

800

1200

1000

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(b) DTA curves














2 On the


2 the less residual


2contained in CO

2-rich gas


2over 4 in





2


0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Tem

pera

ture

(∘C)

100 CO2


97 CO2 + 3 O2

95 CO2 + 5 O2

(a) TG curves

0

04

08

12

16

2

0 10 20 30 40 50 60 70Time (min)

119902(Jmiddotm

inminus1middotm

gminus1)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)

100 CO2


97 CO2 + 3 O2

95 CO2 + 5 O2

(b) DTA curves


95 CO 96 CO 97 CO

98 CO 99 CO 100 CO

2 2 2

2 2 2


97 CO2 100 CO295 CO2







2amount in


95 CO 96 CO 97 CO2 2 2

98 CO2 99 CO2 100 CO2


97 CO2 100 CO295 CO2





2concentration is


2+ 5O



95 CO 96 CO 97 CO2 2 2

98 CO2 99 CO2 100 CO2


97 CO2 100 CO295 CO2




0 1 2 3 4 5 60

15

30

45

60

75

90

Resid

ual c

arbo

n m

olec

ular

ratio

()

O2 concentration ()

1200∘C

1000∘C

1400∘C


2-rich gas flow


2contained in CO



2gas and promote


over 1300∘C



Δ119881

119898

Δ119905

= 119860


119877119879

)

Δ119881

119898=

119898

0minus 119898

119898

0

(10)




0(119904

minus1) is the






Δ119881

119898

Δ119905


119877119879

) (11)



119889119909

119889119905

=

119889 [(119898 minus 119898

0) 119898

0]

119889119905

(12)



percentage of O2



2and CO





0 00005 0001 00015 0002 00025 0003 00035

Air

minus750

minus800

minus850

minus900

minus950

minus1000

minus1050

ln(Δ

119881119898Δ

119905) (s

minus1)



100 CO2

1400∘

95 CO2 + 5 O2


0

00002

00004

00006

00008

0001

0 5 10 15 20 250

30

60

90

120




119864(k

Jmiddotmol

minus1)


1400∘

1198600

(sminus1)

)O2 S



000

001

002

003

004

005

006

007

008

0 200 400 600 800 1000 1200 1400Temperature (∘C)


(1400∘

(1400∘(1400∘

(mgmiddot

min

minus1middotm

gminus1)

minus119889119898119889119905119872





2gas







2 in the CO





0255075

100125150175200225250


(Jmiddotm

gminus1)

minus119902119889119909119889119905


(1400∘

(1400∘(1400∘





2or 95 CO

2+ 5 O

2gas






2gas flow is


2in the CO

2-rich gas flow was


0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Tem

pera

ture

(∘C)



char95 CO2 + 5 O2

coal95 CO2 + 5 O2


atmosphere

00

02

04

06

08

10

12

14

0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

1400

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)



char95 CO2 + 5 O2

coal95 CO2 + 5 O2


atmosphere


2gas flow is






0

10

20

30

40

50

60

70

HCs

(ppm

)

0 100 200 300 400 500 600 700Temperature (∘C)

100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air



flows












2gas






2-


2-rich


2+ 4 O








2+ 1




0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air


0

2000

4000

6000

8000

10000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air




2gas flow as




2gas flow CO



generation




0

20

40

60

80

100

120

0 100 200 300 400 500 600 700

HCs

(ppm

)

Temperature (∘ C)

TG-DTA coal 100 CO2







0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)

TG-DTA coal 100 CO2








2 and temperature


2


2+ 1 O




0

1500

3000

4500

6000

7500

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)








2gas


50

60

70

80

90

100

0 10 20 30 40 50 60

Coa

l wei

ght r

educ

tion

ratio


Coal 95 CO2 + 5 O2 Char 95 CO2 + 5 O2





2-rich



2




technologies


0

05

10

15

20

25

Cum

ulat

ive H

Cs (m

Lmiddotgminus

1)

0 1 2 3 4 5 6O2 ()






0

100

200

300

400

500

600

Cum

ulat

ive C

O (m

Lmiddotgminus

1)


0 1 2 3 4 5 6O2 ()







2-rich



2 from 0 to 5 O











5 Conclusions


2-rich gas flow


2 in CO

2-rich gas and


2and oxygen





2concentra-




2gas


2gas and promote CO

2


higher O2 was in CO







2-rich gas flow




2+ 4 O

2and 98 CO

2+ 2 O

2gas





2gas on the


Acknowledgments



coalrdquo

References













2emissions










2N2 O2CO2and O

2RFG











2CO2mixtures by



2N2
















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation












Flow gas

Flue gas

Sample

Balance


Gas controller


(95sim100 CO2)

Al2O3






Coal


100 CO2 100sim200 20sim40

Char


100 CO2 100 20



Θ = Θ

0+ 120582119905 (7)




0(119898 le 119898



119876



119902 = 120573

119876

lowast

119898

0

(8)



119867 = int

infin

0

119902 (119905) 119889119905 =

120573

119898

0

int

40

0

119876

lowast(119905) 119889119905 =

120573

119898

0

40

sum

119894=0

119876

lowast

119894sdot Δ119905 (9)






20





2absorption)


0

Time (min)

020406080100120140160180200


0 10 20 30 40

119909(m

gmiddotm

gminus1)

sum119876lowast 119894119872

(120583Vmiddotm

inmiddotm

gminus1)



0 10 20 30 40 50 60 70 800

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Time (min)

Tem

pera

ture

(∘C)





tions in flow gas






2absorption)






0

03

06

09

12

15

18

21

0 10 20 30 40 50 60 70 80Time (min)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)

119902(Jmiddotm

inminus1middotm

gminus1)






tions in flow gas


2-


2



case of 95 CO2+ 5 O














2is an endothermic




2+ 5 O


2








0 5 10 15 20 25 30 35 40 45 50Time (min)

0


119909(m

gmiddotm

gminus1)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)



∘












30




2


2+ 5 O

2


2+ 5 O

2gas


0 5 10 15 20 25 30 35 40 45 50Time (min)

0

03

06

09

12

15

18

21

119902(Jmiddotm

inminus1middotm

gminus1)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)



∘








2(119902 =


2+ 5 O

2




2and 95 CO

2+ 5















0 5 10 15 20 25 30 35 40 45 50Time (min)

0

200

400

600

800

10000


119909(m

gmiddotm

gminus1)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(a) TG curves

0

04

08

12

16

2

0 5 10 15 20 25 30 35 40 45 50Time (min)

0

200

400

600

800

1000

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(b) DTA curves


0 10 20 30 40 50 60Time (min)

0


119909(m

gmiddotm

gminus1)

0

200

400

600

800

1000

1200

Tem

pera

ture

(∘C)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(a) TG curves

0 10 20 30 40 50 60Time (min)

0

04

08

12

16

2

0

200

400

600

800

1200

1000

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(b) DTA curves














2 On the


2 the less residual


2contained in CO

2-rich gas


2over 4 in





2


0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Tem

pera

ture

(∘C)

100 CO2


97 CO2 + 3 O2

95 CO2 + 5 O2

(a) TG curves

0

04

08

12

16

2

0 10 20 30 40 50 60 70Time (min)

119902(Jmiddotm

inminus1middotm

gminus1)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)

100 CO2


97 CO2 + 3 O2

95 CO2 + 5 O2

(b) DTA curves


95 CO 96 CO 97 CO

98 CO 99 CO 100 CO

2 2 2

2 2 2


97 CO2 100 CO295 CO2







2amount in


95 CO 96 CO 97 CO2 2 2

98 CO2 99 CO2 100 CO2


97 CO2 100 CO295 CO2





2concentration is


2+ 5O



95 CO 96 CO 97 CO2 2 2

98 CO2 99 CO2 100 CO2


97 CO2 100 CO295 CO2




0 1 2 3 4 5 60

15

30

45

60

75

90

Resid

ual c

arbo

n m

olec

ular

ratio

()

O2 concentration ()

1200∘C

1000∘C

1400∘C


2-rich gas flow


2contained in CO



2gas and promote


over 1300∘C



Δ119881

119898

Δ119905

= 119860


119877119879

)

Δ119881

119898=

119898

0minus 119898

119898

0

(10)




0(119904

minus1) is the






Δ119881

119898

Δ119905


119877119879

) (11)



119889119909

119889119905

=

119889 [(119898 minus 119898

0) 119898

0]

119889119905

(12)



percentage of O2



2and CO





0 00005 0001 00015 0002 00025 0003 00035

Air

minus750

minus800

minus850

minus900

minus950

minus1000

minus1050

ln(Δ

119881119898Δ

119905) (s

minus1)



100 CO2

1400∘

95 CO2 + 5 O2


0

00002

00004

00006

00008

0001

0 5 10 15 20 250

30

60

90

120




119864(k

Jmiddotmol

minus1)


1400∘

1198600

(sminus1)

)O2 S



000

001

002

003

004

005

006

007

008

0 200 400 600 800 1000 1200 1400Temperature (∘C)


(1400∘

(1400∘(1400∘

(mgmiddot

min

minus1middotm

gminus1)

minus119889119898119889119905119872





2gas







2 in the CO





0255075

100125150175200225250


(Jmiddotm

gminus1)

minus119902119889119909119889119905


(1400∘

(1400∘(1400∘





2or 95 CO

2+ 5 O

2gas






2gas flow is


2in the CO

2-rich gas flow was


0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Tem

pera

ture

(∘C)



char95 CO2 + 5 O2

coal95 CO2 + 5 O2


atmosphere

00

02

04

06

08

10

12

14

0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

1400

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)



char95 CO2 + 5 O2

coal95 CO2 + 5 O2


atmosphere


2gas flow is






0

10

20

30

40

50

60

70

HCs

(ppm

)

0 100 200 300 400 500 600 700Temperature (∘C)

100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air



flows












2gas






2-


2-rich


2+ 4 O








2+ 1




0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air


0

2000

4000

6000

8000

10000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air




2gas flow as




2gas flow CO



generation




0

20

40

60

80

100

120

0 100 200 300 400 500 600 700

HCs

(ppm

)

Temperature (∘ C)

TG-DTA coal 100 CO2







0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)

TG-DTA coal 100 CO2








2 and temperature


2


2+ 1 O




0

1500

3000

4500

6000

7500

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)








2gas


50

60

70

80

90

100

0 10 20 30 40 50 60

Coa

l wei

ght r

educ

tion

ratio


Coal 95 CO2 + 5 O2 Char 95 CO2 + 5 O2





2-rich



2




technologies


0

05

10

15

20

25

Cum

ulat

ive H

Cs (m

Lmiddotgminus

1)

0 1 2 3 4 5 6O2 ()






0

100

200

300

400

500

600

Cum

ulat

ive C

O (m

Lmiddotgminus

1)


0 1 2 3 4 5 6O2 ()







2-rich



2 from 0 to 5 O











5 Conclusions


2-rich gas flow


2 in CO

2-rich gas and


2and oxygen





2concentra-




2gas


2gas and promote CO

2


higher O2 was in CO







2-rich gas flow




2+ 4 O

2and 98 CO

2+ 2 O

2gas





2gas on the


Acknowledgments



coalrdquo

References













2emissions










2N2 O2CO2and O

2RFG











2CO2mixtures by



2N2
















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










0

Time (min)

020406080100120140160180200


0 10 20 30 40

119909(m

gmiddotm

gminus1)

sum119876lowast 119894119872

(120583Vmiddotm

inmiddotm

gminus1)



0 10 20 30 40 50 60 70 800

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Time (min)

Tem

pera

ture

(∘C)





tions in flow gas






2absorption)






0

03

06

09

12

15

18

21

0 10 20 30 40 50 60 70 80Time (min)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)

119902(Jmiddotm

inminus1middotm

gminus1)






tions in flow gas


2-


2



case of 95 CO2+ 5 O














2is an endothermic




2+ 5 O


2








0 5 10 15 20 25 30 35 40 45 50Time (min)

0


119909(m

gmiddotm

gminus1)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)



∘












30




2


2+ 5 O

2


2+ 5 O

2gas


0 5 10 15 20 25 30 35 40 45 50Time (min)

0

03

06

09

12

15

18

21

119902(Jmiddotm

inminus1middotm

gminus1)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)



∘








2(119902 =


2+ 5 O

2




2and 95 CO

2+ 5















0 5 10 15 20 25 30 35 40 45 50Time (min)

0

200

400

600

800

10000


119909(m

gmiddotm

gminus1)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(a) TG curves

0

04

08

12

16

2

0 5 10 15 20 25 30 35 40 45 50Time (min)

0

200

400

600

800

1000

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(b) DTA curves


0 10 20 30 40 50 60Time (min)

0


119909(m

gmiddotm

gminus1)

0

200

400

600

800

1000

1200

Tem

pera

ture

(∘C)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(a) TG curves

0 10 20 30 40 50 60Time (min)

0

04

08

12

16

2

0

200

400

600

800

1200

1000

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(b) DTA curves














2 On the


2 the less residual


2contained in CO

2-rich gas


2over 4 in





2


0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Tem

pera

ture

(∘C)

100 CO2


97 CO2 + 3 O2

95 CO2 + 5 O2

(a) TG curves

0

04

08

12

16

2

0 10 20 30 40 50 60 70Time (min)

119902(Jmiddotm

inminus1middotm

gminus1)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)

100 CO2


97 CO2 + 3 O2

95 CO2 + 5 O2

(b) DTA curves


95 CO 96 CO 97 CO

98 CO 99 CO 100 CO

2 2 2

2 2 2


97 CO2 100 CO295 CO2







2amount in


95 CO 96 CO 97 CO2 2 2

98 CO2 99 CO2 100 CO2


97 CO2 100 CO295 CO2





2concentration is


2+ 5O



95 CO 96 CO 97 CO2 2 2

98 CO2 99 CO2 100 CO2


97 CO2 100 CO295 CO2




0 1 2 3 4 5 60

15

30

45

60

75

90

Resid

ual c

arbo

n m

olec

ular

ratio

()

O2 concentration ()

1200∘C

1000∘C

1400∘C


2-rich gas flow


2contained in CO



2gas and promote


over 1300∘C



Δ119881

119898

Δ119905

= 119860


119877119879

)

Δ119881

119898=

119898

0minus 119898

119898

0

(10)




0(119904

minus1) is the






Δ119881

119898

Δ119905


119877119879

) (11)



119889119909

119889119905

=

119889 [(119898 minus 119898

0) 119898

0]

119889119905

(12)



percentage of O2



2and CO





0 00005 0001 00015 0002 00025 0003 00035

Air

minus750

minus800

minus850

minus900

minus950

minus1000

minus1050

ln(Δ

119881119898Δ

119905) (s

minus1)



100 CO2

1400∘

95 CO2 + 5 O2


0

00002

00004

00006

00008

0001

0 5 10 15 20 250

30

60

90

120




119864(k

Jmiddotmol

minus1)


1400∘

1198600

(sminus1)

)O2 S



000

001

002

003

004

005

006

007

008

0 200 400 600 800 1000 1200 1400Temperature (∘C)


(1400∘

(1400∘(1400∘

(mgmiddot

min

minus1middotm

gminus1)

minus119889119898119889119905119872





2gas







2 in the CO





0255075

100125150175200225250


(Jmiddotm

gminus1)

minus119902119889119909119889119905


(1400∘

(1400∘(1400∘





2or 95 CO

2+ 5 O

2gas






2gas flow is


2in the CO

2-rich gas flow was


0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Tem

pera

ture

(∘C)



char95 CO2 + 5 O2

coal95 CO2 + 5 O2


atmosphere

00

02

04

06

08

10

12

14

0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

1400

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)



char95 CO2 + 5 O2

coal95 CO2 + 5 O2


atmosphere


2gas flow is






0

10

20

30

40

50

60

70

HCs

(ppm

)

0 100 200 300 400 500 600 700Temperature (∘C)

100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air



flows












2gas






2-


2-rich


2+ 4 O








2+ 1




0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air


0

2000

4000

6000

8000

10000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air




2gas flow as




2gas flow CO



generation




0

20

40

60

80

100

120

0 100 200 300 400 500 600 700

HCs

(ppm

)

Temperature (∘ C)

TG-DTA coal 100 CO2







0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)

TG-DTA coal 100 CO2








2 and temperature


2


2+ 1 O




0

1500

3000

4500

6000

7500

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)








2gas


50

60

70

80

90

100

0 10 20 30 40 50 60

Coa

l wei

ght r

educ

tion

ratio


Coal 95 CO2 + 5 O2 Char 95 CO2 + 5 O2





2-rich



2




technologies


0

05

10

15

20

25

Cum

ulat

ive H

Cs (m

Lmiddotgminus

1)

0 1 2 3 4 5 6O2 ()






0

100

200

300

400

500

600

Cum

ulat

ive C

O (m

Lmiddotgminus

1)


0 1 2 3 4 5 6O2 ()







2-rich



2 from 0 to 5 O











5 Conclusions


2-rich gas flow


2 in CO

2-rich gas and


2and oxygen





2concentra-




2gas


2gas and promote CO

2


higher O2 was in CO







2-rich gas flow




2+ 4 O

2and 98 CO

2+ 2 O

2gas





2gas on the


Acknowledgments



coalrdquo

References













2emissions










2N2 O2CO2and O

2RFG











2CO2mixtures by



2N2
















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










0 5 10 15 20 25 30 35 40 45 50Time (min)

0


119909(m

gmiddotm

gminus1)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)



∘












30




2


2+ 5 O

2


2+ 5 O

2gas


0 5 10 15 20 25 30 35 40 45 50Time (min)

0

03

06

09

12

15

18

21

119902(Jmiddotm

inminus1middotm

gminus1)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)



∘








2(119902 =


2+ 5 O

2




2and 95 CO

2+ 5















0 5 10 15 20 25 30 35 40 45 50Time (min)

0

200

400

600

800

10000


119909(m

gmiddotm

gminus1)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(a) TG curves

0

04

08

12

16

2

0 5 10 15 20 25 30 35 40 45 50Time (min)

0

200

400

600

800

1000

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(b) DTA curves


0 10 20 30 40 50 60Time (min)

0


119909(m

gmiddotm

gminus1)

0

200

400

600

800

1000

1200

Tem

pera

ture

(∘C)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(a) TG curves

0 10 20 30 40 50 60Time (min)

0

04

08

12

16

2

0

200

400

600

800

1200

1000

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(b) DTA curves














2 On the


2 the less residual


2contained in CO

2-rich gas


2over 4 in





2


0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Tem

pera

ture

(∘C)

100 CO2


97 CO2 + 3 O2

95 CO2 + 5 O2

(a) TG curves

0

04

08

12

16

2

0 10 20 30 40 50 60 70Time (min)

119902(Jmiddotm

inminus1middotm

gminus1)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)

100 CO2


97 CO2 + 3 O2

95 CO2 + 5 O2

(b) DTA curves


95 CO 96 CO 97 CO

98 CO 99 CO 100 CO

2 2 2

2 2 2


97 CO2 100 CO295 CO2







2amount in


95 CO 96 CO 97 CO2 2 2

98 CO2 99 CO2 100 CO2


97 CO2 100 CO295 CO2





2concentration is


2+ 5O



95 CO 96 CO 97 CO2 2 2

98 CO2 99 CO2 100 CO2


97 CO2 100 CO295 CO2




0 1 2 3 4 5 60

15

30

45

60

75

90

Resid

ual c

arbo

n m

olec

ular

ratio

()

O2 concentration ()

1200∘C

1000∘C

1400∘C


2-rich gas flow


2contained in CO



2gas and promote


over 1300∘C



Δ119881

119898

Δ119905

= 119860


119877119879

)

Δ119881

119898=

119898

0minus 119898

119898

0

(10)




0(119904

minus1) is the






Δ119881

119898

Δ119905


119877119879

) (11)



119889119909

119889119905

=

119889 [(119898 minus 119898

0) 119898

0]

119889119905

(12)



percentage of O2



2and CO





0 00005 0001 00015 0002 00025 0003 00035

Air

minus750

minus800

minus850

minus900

minus950

minus1000

minus1050

ln(Δ

119881119898Δ

119905) (s

minus1)



100 CO2

1400∘

95 CO2 + 5 O2


0

00002

00004

00006

00008

0001

0 5 10 15 20 250

30

60

90

120




119864(k

Jmiddotmol

minus1)


1400∘

1198600

(sminus1)

)O2 S



000

001

002

003

004

005

006

007

008

0 200 400 600 800 1000 1200 1400Temperature (∘C)


(1400∘

(1400∘(1400∘

(mgmiddot

min

minus1middotm

gminus1)

minus119889119898119889119905119872





2gas







2 in the CO





0255075

100125150175200225250


(Jmiddotm

gminus1)

minus119902119889119909119889119905


(1400∘

(1400∘(1400∘





2or 95 CO

2+ 5 O

2gas






2gas flow is


2in the CO

2-rich gas flow was


0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Tem

pera

ture

(∘C)



char95 CO2 + 5 O2

coal95 CO2 + 5 O2


atmosphere

00

02

04

06

08

10

12

14

0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

1400

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)



char95 CO2 + 5 O2

coal95 CO2 + 5 O2


atmosphere


2gas flow is






0

10

20

30

40

50

60

70

HCs

(ppm

)

0 100 200 300 400 500 600 700Temperature (∘C)

100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air



flows












2gas






2-


2-rich


2+ 4 O








2+ 1




0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air


0

2000

4000

6000

8000

10000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air




2gas flow as




2gas flow CO



generation




0

20

40

60

80

100

120

0 100 200 300 400 500 600 700

HCs

(ppm

)

Temperature (∘ C)

TG-DTA coal 100 CO2







0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)

TG-DTA coal 100 CO2








2 and temperature


2


2+ 1 O




0

1500

3000

4500

6000

7500

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)








2gas


50

60

70

80

90

100

0 10 20 30 40 50 60

Coa

l wei

ght r

educ

tion

ratio


Coal 95 CO2 + 5 O2 Char 95 CO2 + 5 O2





2-rich



2




technologies


0

05

10

15

20

25

Cum

ulat

ive H

Cs (m

Lmiddotgminus

1)

0 1 2 3 4 5 6O2 ()






0

100

200

300

400

500

600

Cum

ulat

ive C

O (m

Lmiddotgminus

1)


0 1 2 3 4 5 6O2 ()







2-rich



2 from 0 to 5 O











5 Conclusions


2-rich gas flow


2 in CO

2-rich gas and


2and oxygen





2concentra-




2gas


2gas and promote CO

2


higher O2 was in CO







2-rich gas flow




2+ 4 O

2and 98 CO

2+ 2 O

2gas





2gas on the


Acknowledgments



coalrdquo

References













2emissions










2N2 O2CO2and O

2RFG











2CO2mixtures by



2N2
















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










0 5 10 15 20 25 30 35 40 45 50Time (min)

0

200

400

600

800

10000


119909(m

gmiddotm

gminus1)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(a) TG curves

0

04

08

12

16

2

0 5 10 15 20 25 30 35 40 45 50Time (min)

0

200

400

600

800

1000

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(b) DTA curves


0 10 20 30 40 50 60Time (min)

0


119909(m

gmiddotm

gminus1)

0

200

400

600

800

1000

1200

Tem

pera

ture

(∘C)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(a) TG curves

0 10 20 30 40 50 60Time (min)

0

04

08

12

16

2

0

200

400

600

800

1200

1000

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)

100 CO2


99 CO2 + 1 O2

98 CO2 + 2 O2

97 CO2 + 3 O2

95 CO2 + 5 O2

96 CO2 + 4 O2

(b) DTA curves














2 On the


2 the less residual


2contained in CO

2-rich gas


2over 4 in





2


0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Tem

pera

ture

(∘C)

100 CO2


97 CO2 + 3 O2

95 CO2 + 5 O2

(a) TG curves

0

04

08

12

16

2

0 10 20 30 40 50 60 70Time (min)

119902(Jmiddotm

inminus1middotm

gminus1)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)

100 CO2


97 CO2 + 3 O2

95 CO2 + 5 O2

(b) DTA curves


95 CO 96 CO 97 CO

98 CO 99 CO 100 CO

2 2 2

2 2 2


97 CO2 100 CO295 CO2







2amount in


95 CO 96 CO 97 CO2 2 2

98 CO2 99 CO2 100 CO2


97 CO2 100 CO295 CO2





2concentration is


2+ 5O



95 CO 96 CO 97 CO2 2 2

98 CO2 99 CO2 100 CO2


97 CO2 100 CO295 CO2




0 1 2 3 4 5 60

15

30

45

60

75

90

Resid

ual c

arbo

n m

olec

ular

ratio

()

O2 concentration ()

1200∘C

1000∘C

1400∘C


2-rich gas flow


2contained in CO



2gas and promote


over 1300∘C



Δ119881

119898

Δ119905

= 119860


119877119879

)

Δ119881

119898=

119898

0minus 119898

119898

0

(10)




0(119904

minus1) is the






Δ119881

119898

Δ119905


119877119879

) (11)



119889119909

119889119905

=

119889 [(119898 minus 119898

0) 119898

0]

119889119905

(12)



percentage of O2



2and CO





0 00005 0001 00015 0002 00025 0003 00035

Air

minus750

minus800

minus850

minus900

minus950

minus1000

minus1050

ln(Δ

119881119898Δ

119905) (s

minus1)



100 CO2

1400∘

95 CO2 + 5 O2


0

00002

00004

00006

00008

0001

0 5 10 15 20 250

30

60

90

120




119864(k

Jmiddotmol

minus1)


1400∘

1198600

(sminus1)

)O2 S



000

001

002

003

004

005

006

007

008

0 200 400 600 800 1000 1200 1400Temperature (∘C)


(1400∘

(1400∘(1400∘

(mgmiddot

min

minus1middotm

gminus1)

minus119889119898119889119905119872





2gas







2 in the CO





0255075

100125150175200225250


(Jmiddotm

gminus1)

minus119902119889119909119889119905


(1400∘

(1400∘(1400∘





2or 95 CO

2+ 5 O

2gas






2gas flow is


2in the CO

2-rich gas flow was


0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Tem

pera

ture

(∘C)



char95 CO2 + 5 O2

coal95 CO2 + 5 O2


atmosphere

00

02

04

06

08

10

12

14

0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

1400

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)



char95 CO2 + 5 O2

coal95 CO2 + 5 O2


atmosphere


2gas flow is






0

10

20

30

40

50

60

70

HCs

(ppm

)

0 100 200 300 400 500 600 700Temperature (∘C)

100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air



flows












2gas






2-


2-rich


2+ 4 O








2+ 1




0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air


0

2000

4000

6000

8000

10000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air




2gas flow as




2gas flow CO



generation




0

20

40

60

80

100

120

0 100 200 300 400 500 600 700

HCs

(ppm

)

Temperature (∘ C)

TG-DTA coal 100 CO2







0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)

TG-DTA coal 100 CO2








2 and temperature


2


2+ 1 O




0

1500

3000

4500

6000

7500

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)








2gas


50

60

70

80

90

100

0 10 20 30 40 50 60

Coa

l wei

ght r

educ

tion

ratio


Coal 95 CO2 + 5 O2 Char 95 CO2 + 5 O2





2-rich



2




technologies


0

05

10

15

20

25

Cum

ulat

ive H

Cs (m

Lmiddotgminus

1)

0 1 2 3 4 5 6O2 ()






0

100

200

300

400

500

600

Cum

ulat

ive C

O (m

Lmiddotgminus

1)


0 1 2 3 4 5 6O2 ()







2-rich



2 from 0 to 5 O











5 Conclusions


2-rich gas flow


2 in CO

2-rich gas and


2and oxygen





2concentra-




2gas


2gas and promote CO

2


higher O2 was in CO







2-rich gas flow




2+ 4 O

2and 98 CO

2+ 2 O

2gas





2gas on the


Acknowledgments



coalrdquo

References













2emissions










2N2 O2CO2and O

2RFG











2CO2mixtures by



2N2
















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Tem

pera

ture

(∘C)

100 CO2


97 CO2 + 3 O2

95 CO2 + 5 O2

(a) TG curves

0

04

08

12

16

2

0 10 20 30 40 50 60 70Time (min)

119902(Jmiddotm

inminus1middotm

gminus1)

0

200

400

600

800

1000

1200

1400

Tem

pera

ture

(∘C)

100 CO2


97 CO2 + 3 O2

95 CO2 + 5 O2

(b) DTA curves


95 CO 96 CO 97 CO

98 CO 99 CO 100 CO

2 2 2

2 2 2


97 CO2 100 CO295 CO2







2amount in


95 CO 96 CO 97 CO2 2 2

98 CO2 99 CO2 100 CO2


97 CO2 100 CO295 CO2





2concentration is


2+ 5O



95 CO 96 CO 97 CO2 2 2

98 CO2 99 CO2 100 CO2


97 CO2 100 CO295 CO2




0 1 2 3 4 5 60

15

30

45

60

75

90

Resid

ual c

arbo

n m

olec

ular

ratio

()

O2 concentration ()

1200∘C

1000∘C

1400∘C


2-rich gas flow


2contained in CO



2gas and promote


over 1300∘C



Δ119881

119898

Δ119905

= 119860


119877119879

)

Δ119881

119898=

119898

0minus 119898

119898

0

(10)




0(119904

minus1) is the






Δ119881

119898

Δ119905


119877119879

) (11)



119889119909

119889119905

=

119889 [(119898 minus 119898

0) 119898

0]

119889119905

(12)



percentage of O2



2and CO





0 00005 0001 00015 0002 00025 0003 00035

Air

minus750

minus800

minus850

minus900

minus950

minus1000

minus1050

ln(Δ

119881119898Δ

119905) (s

minus1)



100 CO2

1400∘

95 CO2 + 5 O2


0

00002

00004

00006

00008

0001

0 5 10 15 20 250

30

60

90

120




119864(k

Jmiddotmol

minus1)


1400∘

1198600

(sminus1)

)O2 S



000

001

002

003

004

005

006

007

008

0 200 400 600 800 1000 1200 1400Temperature (∘C)


(1400∘

(1400∘(1400∘

(mgmiddot

min

minus1middotm

gminus1)

minus119889119898119889119905119872





2gas







2 in the CO





0255075

100125150175200225250


(Jmiddotm

gminus1)

minus119902119889119909119889119905


(1400∘

(1400∘(1400∘





2or 95 CO

2+ 5 O

2gas






2gas flow is


2in the CO

2-rich gas flow was


0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Tem

pera

ture

(∘C)



char95 CO2 + 5 O2

coal95 CO2 + 5 O2


atmosphere

00

02

04

06

08

10

12

14

0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

1400

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)



char95 CO2 + 5 O2

coal95 CO2 + 5 O2


atmosphere


2gas flow is






0

10

20

30

40

50

60

70

HCs

(ppm

)

0 100 200 300 400 500 600 700Temperature (∘C)

100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air



flows












2gas






2-


2-rich


2+ 4 O








2+ 1




0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air


0

2000

4000

6000

8000

10000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air




2gas flow as




2gas flow CO



generation




0

20

40

60

80

100

120

0 100 200 300 400 500 600 700

HCs

(ppm

)

Temperature (∘ C)

TG-DTA coal 100 CO2







0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)

TG-DTA coal 100 CO2








2 and temperature


2


2+ 1 O




0

1500

3000

4500

6000

7500

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)








2gas


50

60

70

80

90

100

0 10 20 30 40 50 60

Coa

l wei

ght r

educ

tion

ratio


Coal 95 CO2 + 5 O2 Char 95 CO2 + 5 O2





2-rich



2




technologies


0

05

10

15

20

25

Cum

ulat

ive H

Cs (m

Lmiddotgminus

1)

0 1 2 3 4 5 6O2 ()






0

100

200

300

400

500

600

Cum

ulat

ive C

O (m

Lmiddotgminus

1)


0 1 2 3 4 5 6O2 ()







2-rich



2 from 0 to 5 O











5 Conclusions


2-rich gas flow


2 in CO

2-rich gas and


2and oxygen





2concentra-




2gas


2gas and promote CO

2


higher O2 was in CO







2-rich gas flow




2+ 4 O

2and 98 CO

2+ 2 O

2gas





2gas on the


Acknowledgments



coalrdquo

References













2emissions










2N2 O2CO2and O

2RFG











2CO2mixtures by



2N2
















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










95 CO 96 CO 97 CO2 2 2

98 CO2 99 CO2 100 CO2


97 CO2 100 CO295 CO2




0 1 2 3 4 5 60

15

30

45

60

75

90

Resid

ual c

arbo

n m

olec

ular

ratio

()

O2 concentration ()

1200∘C

1000∘C

1400∘C


2-rich gas flow


2contained in CO



2gas and promote


over 1300∘C



Δ119881

119898

Δ119905

= 119860


119877119879

)

Δ119881

119898=

119898

0minus 119898

119898

0

(10)




0(119904

minus1) is the






Δ119881

119898

Δ119905


119877119879

) (11)



119889119909

119889119905

=

119889 [(119898 minus 119898

0) 119898

0]

119889119905

(12)



percentage of O2



2and CO





0 00005 0001 00015 0002 00025 0003 00035

Air

minus750

minus800

minus850

minus900

minus950

minus1000

minus1050

ln(Δ

119881119898Δ

119905) (s

minus1)



100 CO2

1400∘

95 CO2 + 5 O2


0

00002

00004

00006

00008

0001

0 5 10 15 20 250

30

60

90

120




119864(k

Jmiddotmol

minus1)


1400∘

1198600

(sminus1)

)O2 S



000

001

002

003

004

005

006

007

008

0 200 400 600 800 1000 1200 1400Temperature (∘C)


(1400∘

(1400∘(1400∘

(mgmiddot

min

minus1middotm

gminus1)

minus119889119898119889119905119872





2gas







2 in the CO





0255075

100125150175200225250


(Jmiddotm

gminus1)

minus119902119889119909119889119905


(1400∘

(1400∘(1400∘





2or 95 CO

2+ 5 O

2gas






2gas flow is


2in the CO

2-rich gas flow was


0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Tem

pera

ture

(∘C)



char95 CO2 + 5 O2

coal95 CO2 + 5 O2


atmosphere

00

02

04

06

08

10

12

14

0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

1400

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)



char95 CO2 + 5 O2

coal95 CO2 + 5 O2


atmosphere


2gas flow is






0

10

20

30

40

50

60

70

HCs

(ppm

)

0 100 200 300 400 500 600 700Temperature (∘C)

100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air



flows












2gas






2-


2-rich


2+ 4 O








2+ 1




0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air


0

2000

4000

6000

8000

10000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air




2gas flow as




2gas flow CO



generation




0

20

40

60

80

100

120

0 100 200 300 400 500 600 700

HCs

(ppm

)

Temperature (∘ C)

TG-DTA coal 100 CO2







0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)

TG-DTA coal 100 CO2








2 and temperature


2


2+ 1 O




0

1500

3000

4500

6000

7500

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)








2gas


50

60

70

80

90

100

0 10 20 30 40 50 60

Coa

l wei

ght r

educ

tion

ratio


Coal 95 CO2 + 5 O2 Char 95 CO2 + 5 O2





2-rich



2




technologies


0

05

10

15

20

25

Cum

ulat

ive H

Cs (m

Lmiddotgminus

1)

0 1 2 3 4 5 6O2 ()






0

100

200

300

400

500

600

Cum

ulat

ive C

O (m

Lmiddotgminus

1)


0 1 2 3 4 5 6O2 ()







2-rich



2 from 0 to 5 O











5 Conclusions


2-rich gas flow


2 in CO

2-rich gas and


2and oxygen





2concentra-




2gas


2gas and promote CO

2


higher O2 was in CO







2-rich gas flow




2+ 4 O

2and 98 CO

2+ 2 O

2gas





2gas on the


Acknowledgments



coalrdquo

References













2emissions










2N2 O2CO2and O

2RFG











2CO2mixtures by



2N2
















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










0 00005 0001 00015 0002 00025 0003 00035

Air

minus750

minus800

minus850

minus900

minus950

minus1000

minus1050

ln(Δ

119881119898Δ

119905) (s

minus1)



100 CO2

1400∘

95 CO2 + 5 O2


0

00002

00004

00006

00008

0001

0 5 10 15 20 250

30

60

90

120




119864(k

Jmiddotmol

minus1)


1400∘

1198600

(sminus1)

)O2 S



000

001

002

003

004

005

006

007

008

0 200 400 600 800 1000 1200 1400Temperature (∘C)


(1400∘

(1400∘(1400∘

(mgmiddot

min

minus1middotm

gminus1)

minus119889119898119889119905119872





2gas







2 in the CO





0255075

100125150175200225250


(Jmiddotm

gminus1)

minus119902119889119909119889119905


(1400∘

(1400∘(1400∘





2or 95 CO

2+ 5 O

2gas






2gas flow is


2in the CO

2-rich gas flow was


0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Tem

pera

ture

(∘C)



char95 CO2 + 5 O2

coal95 CO2 + 5 O2


atmosphere

00

02

04

06

08

10

12

14

0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

1400

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)



char95 CO2 + 5 O2

coal95 CO2 + 5 O2


atmosphere


2gas flow is






0

10

20

30

40

50

60

70

HCs

(ppm

)

0 100 200 300 400 500 600 700Temperature (∘C)

100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air



flows












2gas






2-


2-rich


2+ 4 O








2+ 1




0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air


0

2000

4000

6000

8000

10000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air




2gas flow as




2gas flow CO



generation




0

20

40

60

80

100

120

0 100 200 300 400 500 600 700

HCs

(ppm

)

Temperature (∘ C)

TG-DTA coal 100 CO2







0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)

TG-DTA coal 100 CO2








2 and temperature


2


2+ 1 O




0

1500

3000

4500

6000

7500

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)








2gas


50

60

70

80

90

100

0 10 20 30 40 50 60

Coa

l wei

ght r

educ

tion

ratio


Coal 95 CO2 + 5 O2 Char 95 CO2 + 5 O2





2-rich



2




technologies


0

05

10

15

20

25

Cum

ulat

ive H

Cs (m

Lmiddotgminus

1)

0 1 2 3 4 5 6O2 ()






0

100

200

300

400

500

600

Cum

ulat

ive C

O (m

Lmiddotgminus

1)


0 1 2 3 4 5 6O2 ()







2-rich



2 from 0 to 5 O











5 Conclusions


2-rich gas flow


2 in CO

2-rich gas and


2and oxygen





2concentra-




2gas


2gas and promote CO

2


higher O2 was in CO







2-rich gas flow




2+ 4 O

2and 98 CO

2+ 2 O

2gas





2gas on the


Acknowledgments



coalrdquo

References













2emissions










2N2 O2CO2and O

2RFG











2CO2mixtures by



2N2
















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

14000


119909(m

gmiddotm

gminus1)

Tem

pera

ture

(∘C)



char95 CO2 + 5 O2

coal95 CO2 + 5 O2


atmosphere

00

02

04

06

08

10

12

14

0 10 20 30 40 50 60 70Time (min)

0

200

400

600

800

1000

1200

1400

119902(Jmiddotm

inminus1middotm

gminus1)

Tem

pera

ture

(∘C)



char95 CO2 + 5 O2

coal95 CO2 + 5 O2


atmosphere


2gas flow is






0

10

20

30

40

50

60

70

HCs

(ppm

)

0 100 200 300 400 500 600 700Temperature (∘C)

100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air



flows












2gas






2-


2-rich


2+ 4 O








2+ 1




0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air


0

2000

4000

6000

8000

10000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air




2gas flow as




2gas flow CO



generation




0

20

40

60

80

100

120

0 100 200 300 400 500 600 700

HCs

(ppm

)

Temperature (∘ C)

TG-DTA coal 100 CO2







0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)

TG-DTA coal 100 CO2








2 and temperature


2


2+ 1 O




0

1500

3000

4500

6000

7500

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)








2gas


50

60

70

80

90

100

0 10 20 30 40 50 60

Coa

l wei

ght r

educ

tion

ratio


Coal 95 CO2 + 5 O2 Char 95 CO2 + 5 O2





2-rich



2




technologies


0

05

10

15

20

25

Cum

ulat

ive H

Cs (m

Lmiddotgminus

1)

0 1 2 3 4 5 6O2 ()






0

100

200

300

400

500

600

Cum

ulat

ive C

O (m

Lmiddotgminus

1)


0 1 2 3 4 5 6O2 ()







2-rich



2 from 0 to 5 O











5 Conclusions


2-rich gas flow


2 in CO

2-rich gas and


2and oxygen





2concentra-




2gas


2gas and promote CO

2


higher O2 was in CO







2-rich gas flow




2+ 4 O

2and 98 CO

2+ 2 O

2gas





2gas on the


Acknowledgments



coalrdquo

References













2emissions










2N2 O2CO2and O

2RFG











2CO2mixtures by



2N2
















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air


0

2000

4000

6000

8000

10000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)


100 CO2

1 O2

2 O2

3 O2

4 O2

5 O2Air




2gas flow as




2gas flow CO



generation




0

20

40

60

80

100

120

0 100 200 300 400 500 600 700

HCs

(ppm

)

Temperature (∘ C)

TG-DTA coal 100 CO2







0

1500

3000

4500

6000

7500

9000

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)

TG-DTA coal 100 CO2








2 and temperature


2


2+ 1 O




0

1500

3000

4500

6000

7500

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)








2gas


50

60

70

80

90

100

0 10 20 30 40 50 60

Coa

l wei

ght r

educ

tion

ratio


Coal 95 CO2 + 5 O2 Char 95 CO2 + 5 O2





2-rich



2




technologies


0

05

10

15

20

25

Cum

ulat

ive H

Cs (m

Lmiddotgminus

1)

0 1 2 3 4 5 6O2 ()






0

100

200

300

400

500

600

Cum

ulat

ive C

O (m

Lmiddotgminus

1)


0 1 2 3 4 5 6O2 ()







2-rich



2 from 0 to 5 O











5 Conclusions


2-rich gas flow


2 in CO

2-rich gas and


2and oxygen





2concentra-




2gas


2gas and promote CO

2


higher O2 was in CO







2-rich gas flow




2+ 4 O

2and 98 CO

2+ 2 O

2gas





2gas on the


Acknowledgments



coalrdquo

References













2emissions










2N2 O2CO2and O

2RFG











2CO2mixtures by



2N2
















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










0

1500

3000

4500

6000

7500

0 200 400 600 800 1000 1200 1400

CO (p

pm)

Temperature (∘C)








2gas


50

60

70

80

90

100

0 10 20 30 40 50 60

Coa

l wei

ght r

educ

tion

ratio


Coal 95 CO2 + 5 O2 Char 95 CO2 + 5 O2





2-rich



2




technologies


0

05

10

15

20

25

Cum

ulat

ive H

Cs (m

Lmiddotgminus

1)

0 1 2 3 4 5 6O2 ()






0

100

200

300

400

500

600

Cum

ulat

ive C

O (m

Lmiddotgminus

1)


0 1 2 3 4 5 6O2 ()







2-rich



2 from 0 to 5 O











5 Conclusions


2-rich gas flow


2 in CO

2-rich gas and


2and oxygen





2concentra-




2gas


2gas and promote CO

2


higher O2 was in CO







2-rich gas flow




2+ 4 O

2and 98 CO

2+ 2 O

2gas





2gas on the


Acknowledgments



coalrdquo

References













2emissions










2N2 O2CO2and O

2RFG











2CO2mixtures by



2N2
















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation















5 Conclusions


2-rich gas flow


2 in CO

2-rich gas and


2and oxygen





2concentra-




2gas


2gas and promote CO

2


higher O2 was in CO







2-rich gas flow




2+ 4 O

2and 98 CO

2+ 2 O

2gas





2gas on the


Acknowledgments



coalrdquo

References













2emissions










2N2 O2CO2and O

2RFG











2CO2mixtures by



2N2
















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation











2N2 O2CO2and O

2RFG











2CO2mixtures by



2N2
















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation











RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation









research article measurements of gasification ...ments with coal and char at high temperature;...

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