production of useful fuels and electricity from...

Production of Useful Fuels and Electricity from Biomass and Waste Resources

Kunio Yoshikawa

Frontier Research Center, Tokyo Institute of Technology, Yokohama 226-8502, Japan

Up to now, the only solution for utilization of solid wastes including biomass as energy resources is to incinerate them and to use the produced heat directly or to convert the produced heat into electric power employing boilers/steam turbines. Tokyo Institute of Technology is developing and commercializing total technologies to convert unutilized resources such as solid wastes and biomass into high value added energy resources (solid fuel, gaseous fuel, liquid fuel and electric power) by combining various technologies which have been jointly developed with many companies. This paper focuses on R&D and successful commercial applications of these technologies. The content of the technologies are as follows. Solid Fuel Production Technology: The hydrothermal treatment technology can convert unutilized resources with various shapes, heating values and moisture contents into uniform dry powder-like solid fuels with the heating value equivalent to coal. Liquid Fuel Production Technology: Gasoline or diesel equivalent fuel oils can be produced from waste plastics by employing the pyrolytic reforming oil production technology and from waste cooking oils or plant oils by employing the dry-type alkali catalyst biodiesel production technology. The emulsion fuel which is a mixture of oil and water can reduce emissions as well as improve thermal efficiency of boilers. Gasification and Power Generation Technology: The gasification technologies can produce low to medium calorific gases from solid fuels by employing pyrolysis and reforming or steam gasification technologies. Electric power can be generated from this low to medium calorific gases by employing internal combustion engines.

Index Terms—Biomass, Fuel production, Power generation, Wastes

I. INTRODUCTION Up to now, the only commercialized ways of waste treatment are mass land-filling and mass burning. In Japan, most of burnable wastes are incinerated, but not in other countries, and still land-filling is the most popular way of waste treatment all over the world. But the world recent trend is to prohibit or limit land-filling of wastes while citizens do not want to increase waste incineration in developed countries as well as developing countries. On the other hand, segregation of wastes is becoming popular in the developed countries and we have limited solutions on the usage of segregated wastes. Thus we have to find out the utilization ways alternative to incineration for each segregated waste. Based on this background, Tokyo Institute of Technology is focusing on development and commercialization of new technologies for the utilization of segregated wastes as well as mixed wastes as new energy resources. In general, the economical feasibility of new energy resources are not so good, but in the case of wastes, we can get revenue first by treating wastes and second by selling the product (electricity, steam, hot water, fuels, etc.). These technologies cover total technologies ranging from pre-treatment to final energy production. This paper introduces overview of these technologies.

II. SOLID FUEL PRODUCTION TECHNOLOGY (RRS) Pre-treatment of wastes requires crushing, drying and deodorizing, which are normally different processes. But we have devised innovative hydrothermal pre-treatment system named as the RRS (Resource Recycling System) which can perform these three pre-treatment functions in one process

utilizing high pressure saturated steam. This technology is characterized by low energy consumption for drying. Figure 1 shows the operating principle of the RRS and Fig.2 shows a photograph of its commercial plant. Figures 3 and 4 show the photographs of raw material and products.

Solid wastes are fed into the reactor, and then, 200C, 2MPa saturated steam is supplied into the reactor for about 30 minutes and the blades installed inside the reactor rotates to mix the wastes for about 10 minutes. Then the product is discharged after extracting steam. The product is powder-like substance and the moisture content is almost the same as the raw material, but easily to be dried by natural drying. This means that this RRS process itself is not a drying process, and drying can be done using natural energy which results in low energy consumption for drying. There is almost no bad smell in the solid products, and the products can be used as liquid and solid organic fertilizers (in the case of biomass such as sewage sludge, food residue and excrement) or solid fuels (in the case of mixed wastes containing plastics like municipal solid wastes [MSW]) which can be easily mixed with coal for power generation or cement production. For MSW treatment, the RRS technology has significant technical and commercial advantages over conventional incineration technologies such as below. - The RRS is virtually emission free process, no emission

of dioxins, NOx, SOx, dust, etc. If required, waste water can be treated to utilize as a boiler feed water, so no waste water discharge is possible.

- The RRS product can be utilized as a solid fuel, especially for co-firing with coal.

- The capital and running costs of the RRS facility are almost half of those of conventional incinerators.

- The permission of installation of the RRS facility is much

easier to obtain compared with conventional incinerators because it is an emission free process.

- By increasing the pressure of the saturated steam up to 2.5MPa, PVC will be pyrolyzed to discharge chlorine in the form of HCl, which will become safety inorganic salt by the reaction with the alkaline contents in MSW. Thus there is no chlorine emission when we burn the product fuel.

Figure 2 shows a photograph of a commercial hospital waste treatment facility applying the RRS technology in Japan. The inner volume of the reactor is 3m3 and this facility can treat 50-60 hospital waste boxes per batch. The average weight of one box is about 7kg and one batch requires about 4 hours. The facility has been commercially operated for nearly two years.

Fig.1 Operating principle of the RRS

Fig.2 Photograph of the RRS commercial plant

Fig.3 Before treatment by the RRS

Fig.4 After treatment by the RRS

III. LIQUID FUEL PRODUCTION TECHNOLOGY

A. Fuel Oil Production from Waste Plastics and Oils By use of the pyrolysis and catalytic reforming processes,

waste plastics and oils (mechanical) can be converted into fuel oil. Figure 5 shows its operating principle. Waste plastics or oils are pyrolyzed in an externally heated reactor and are vaporized. By cooling, this vapor condenses and becomes oil, but this oil is mixture of light oils and heavy oils, and the quality as a fuel is not so good. But as shown in Fig.6, by passing this vapor through a reforming catalyst, its molecule is cut, and good quality lighter oils can be produced. These fuel oils can be utilized alternative to gasoline, kerosene and diesel oils.

This technology has been commercialized in Japan for metal (gold and cupper) and oil recovery from waste mobile phones and computers (Fig.7) and oil and carbon recovery from waste toner (Fig.8). A new commercial plant for cupper wire and oil recovery from waste electric wires will be operational soon.

Fig.5 Fuel oil production from waste plastics and oils

Silencer

Watertreatment

・Operating sytem

・Stirring unit

・Boiler

・Feeding hopper

・Reactor

ProductProduct・・CompostCompost

・・EnergyEnergy

200oC・2MPa

Silencer

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・Operating sytem

・Stirring unit

・Boiler

・Feeding hopper

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ProductProduct・・CompostCompost

・・EnergyEnergy

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Residue recovery

Oil tank

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No.2 CondenserPyrolyzer

Oil tank

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Oil pump

Circulation pumpHeated extruder

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Waste plastics

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Oil recovery


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Fig.6 Carbon number distribution Fig.7 Commercial plant for metal and oil recovery from waste plastics and computers (2ton/batch/4 hours) Fig.8 Commercial plant for oil and carbon recovery from waste toner (2ton/batch/4 hours)

B. Biodiesel Fuel Production from Plant Oil and Waste Cooking Oil Conventional biodiesel fuel (BDF) production process

employing the alkaline catalyst method shown in Fig.9 has following disadvantages: 1) Raw oil with high FFA and water content can not be used. 2) Cost increase due to low conversion efficiency, 2 steps reaction, excess amount requirement of methanol and catalyst. 3) A large amount of basic waste water is produced from water washing process. 4) Cost increase and deteriorating of produced BDF due to heating and evaporation for drying.

In order to solve these problems, we have developed a new advanced dry BDF production process shown in Fig.10. This process has following advantages: 1) Raw oil with high FFA

and water content can be used by removing water and FFA through a special pretreatment process. 2) Cost reduction is possible due to high conversion efficiency (>99.5%), 1 step reaction, theoretical amount requirement of methanol and catalyst. 3) No waste water is produced. 4) High performance BDF is produced by the low temperature dry purifying process (water content in BDF: <200ppm).

This dry BDF production process has been well commercialized in Japan in small-scale (Fig.11), medium-scale (Fig.12) and large-scale (Fig.13). The total production was over 12,000kl and total running distances were over 50,000,000km. The produced BDF is applicable to common rail direct injection diesel engines. Up to now, 230 garbage collect cars have been running on B100 (biodiesel 100%) produced by this dry process technology from waste edible oil for 5 years without crucial trouble. Fig.9 Conventional BDF production process employing alkaline catalyst method

Fig.10 New advanced dry BDF production process

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Reaction (2 steps)Methanol:30%

NaOH:3%

Purification-Gravitational separation-Water washing-Drying by evaporation

Biodiesel Fuel

Dissolving NaOHinto Methanol

-Crude Glycerin is purified by neutralization anddistillation.

Virgin Vegetable Oil

Reaction (2 steps)Methanol:30%

NaOH:3%

Purification-Gravitational separation-Water washing-Drying by evaporation

Biodiesel Fuel

Dissolving NaOHinto Methanol

-Crude Glycerin is purified by neutralization anddistillation.

Virgin Vegetable OilAnimal Fat

Waste Edible Oil

Removing water, FFAand impurities by

evaporation.

Reaction(1 step)Methanol:15%

KOH:1.5%

Purification-Gravitational separation

-Adsorption column-Centrifuge treat

-Decompression remove

Biodiesel Fuel

Dissolving KOH into Methanol

Crude Glycerin ispurified by neutralization and distillation or directly using for boiler fuel.

Virgin Vegetable OilAnimal Fat

Waste Edible Oil

Removing water, FFAand impurities by

evaporation.

Reaction(1 step)Methanol:15%

KOH:1.5%

Purification-Gravitational separation

-Adsorption column-Centrifuge treat

-Decompression remove

Biodiesel Fuel

Dissolving KOH into Methanol

Crude Glycerin ispurified by neutralization and distillation or directly using for boiler fuel.

Fig.11 Small-scale BDF production facility (20ℓ/batch) Fig.12 Medium-scale BDF production facility (200ℓ/batch)

Fig.13 Large-scale BDF production facility (5000ℓ/day)

C. Emulsion Fuel Production It is known that water emulsified fuel has an effect of

suppressing NOx and dust emissions. But conventional emulsion fuel production processes require addition of surface active agents to prevent separation of oil and water, which significantly deteriorates the economical feasibility of the emulsion fuel. Simultaneously, it is said that saving of fuel is

also possible. But it is not yet shown clearly what the reason is. We have successfully excluded the necessity of surface

active agents by mixing oil and water just before combustion as shown in Fig.14. An application test of this emulsion fuel to a boiler (Fig.15) effectively demonstrated that suppression of NOx and dust emissions is possible (Figs.16 and 17) and improvement of thermal efficiency is also possible by adequately controlling the excess air ratio and water content in the emulsion fuel (Fig.18).

Commercial application of this emulsion fuel to several industrial boilers (Fig.19) has successfully demonstrated that these boilers have been continuously operated for more than a half year without any troubles, suppression of NOx and dust emissions is possible and 5-10% energy saving is possible. In addition, periodical maintenance inspection revealed that the inner surface of boilers became dramatically clean after usage of the emulsion fuel, which should be one cause of improvement of the thermal efficiency. Fig.14 Emulsion fuel production without surface active agents

Fig.15 Boiler testing of the emulsion fuel (1500kg/h) Fig.16 NOx emission as functions of excess air ratio and water content in the emulsion fuel

WWaterater

1010～～3355％％

Line mixer 1

Emulsified Emulsified fuelfuel

Pre-stirring

The first stirring The second stirring

Bunker ABunker A

6565～～9090％％

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WWaterater

1010～～3355％％

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Emulsified Emulsified fuelfuel

Pre-stirring

The first stirring The second stirring

Bunker ABunker A

6565～～9090％％

Line mixer 2

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n of

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Fig.17 Dust emission as functions of excess air ratio and water content in the emulsion fuel Fig.18 Thermal efficiency as functions of excess air ratio and water content in the emulsion fuel Fig.19 Commercial application of the emulsion fuel for a industrial boiler

IV. GASIFICATION AND POWER GENERATION TECHNOLOGY

A. Low Calorific Gas Production (STAR-MEET)

Figure 20 shows a typical system flow of the STAR-MEET system. Solid fuels are fed into a fixed-bed pyrolyzer using a continuous feed device. Thermal energy for pyrolysis of the solid fuels is supplied from the partial combustion of char at the bottom of the pyrolyzer or melting furnace. Residual ashes are extracted from the bottom of the pyrolyzer in the form of

calcinated ashes or from the melting furnace in the form of molten slag. Pyrolysis gas contains H2, CO, CH4, N2, CO2, light hydrocarbon and tar. In the reformer, tar and soot components are reformed with high temperature steam in the following endothermic reactions;

CnHm + nH2O nCO + (n+m/2)H2 (1)

C + H2O H2 + CO (2) These reactions are activated under the condition of high temperature over 800C. To sustain this temperature, high temperature steam is employed as well as using high temperature air for partial combustion of the pyrolysis gas. Main components of the reformed gas are H2, CO, CO2, N2,

CH4 and gaseous hydrocarbons such as C2H2. High temperature steam and air are produced from a high efficiency heat exchanger with hot gas from a furnace burning low calorific fuel gas. The thermal energy of the reformed gas is used for making saturated steam and hot air for the pyrolysis stage. Impurities such as HCl, H2S, etc. in the reformed gas are removed in the purifier, which is a scrubber (wet) type and/or a dry type such as a dust filter or an impurity adsorption device. The recovered fly ashes (mainly soot) are supplied into the pyrolyzer again, and the condensed water originated from the moisture in the solid fuels and the steam supplied for reforming is adequately treated and discharged. Finally this purified fuel gas is used as a fuel for an engine with a power generator and for a low calorific gas burning furnace with a heat exchanger.

Fig.20 System flow of the STAR-MEET system

Heating value of gaseous fuels produced in the STAR-MEET system are as low as 1/10 of that of natural gas, and there is almost no established energy conversion methods for such low calorific gases. Therefore, we developed a dual-fueled diesel engine for burning low calorific gases. Figure 21 shows its operating principle. At the start of the plant operation, the engine is fueled by light oil only. Then the produced low calorific gas is gradually mixed into the combustion air, and in the steady state operation, 20-30% of the total thermal input is supplied by light oil, and 70-80% of

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the total thermal input is supplied by low calorific gas. With this method, it is possible to keep the electrical output constant by controlling the amount of light oil supply even if the heating value of the gas fluctuates. Figure 21 shows the thermal efficiency and NOx emission as a function of the fuel gas rate (thermal input to the engine from fuel gas/total thermal input to the engine) of a duel-fueled diesel engine. This figure shows that up to about 80% fuel gas rate can be achievable with almost no substantial drop of the thermal efficiency while significantly suppressing NOx emission. This NOx reduction is due to decrease of oxygen concentration and flame temperature by introducing low calorific gas into the combustion air. Fig.21 Operating principle, thermal efficiency and NOx emission of a dual-fueled diesel engine Figures 22 and 23 show the system flow and the photograph of the commercial small-scale STAR-MEET system installed in Japan, respectively. The system utilizes about 100 kg/hour of chicken manure as a fuel which is pre-dried by the hot air produced by recovering body heat of chickens. The system is mainly composed of an air-blown updraft type fixed bed gasifier, a reformer, gas purification components and a dual-fueled diesel engine (64kW). Hot water generated from the dual-fueled diesel engine is used for drying chicken manure. Fig.22 Block flow diagram of the STAR-MEET system for chicken manure

Fig.23 Photograph of the commercial STAR-MEET facility This plant was successfully operated for 90 days continuous feed of chicken manure and continuous extraction of ash. Figure 24 shows the results of 90 days continuous operation. From this figure, we confirmed that although the first half of the operation showed some fluctuation, in the latter half of the operation, the heating value of the reformed gas increased and became stable at around our target value of 4MJ/Nm3. Further, the un-burnt carbon in ash is almost less than 5% during the latter half operation, so it has been confirmed that the chicken manure has successfully been gasified stably. The continuous feeding system and the ash extracting system were trouble free during the continuous operation. The residual ash with low carbon content can be sold as a fertilizer due to their rich contents of phosphorous and potassium and recent high rise of prices of these nutrients for chemical fertilizers. High-temperature air reforming effectively suppressed tar formation, and there was no significant condensation of tar nor dust in the downstream components after this long-term continuous operation. We have also successfully demonstrated 55 days continuous daily operation of the dual-fueled diesel engine generator. Table 1 shows the total energy balance of the commercial plant. In this table, the cold gas efficiency = chemical energy of the reformed gas/thermal energy of the chicken manure supplied into the gasifier and the gross thermal efficiency = electrical output of the engine/ thermal energy of the chicken manure supplied into the gasifier. From this table we can confirm that the cold gas efficiency, the carbon conversion efficiency and the gross thermal efficiency of 73.8%, 96.6% and 21.8%, respectively were achieved even though that chicken manure is difficult to be gasified compared with woody biomass due to its lower heating value and higher ash content.

Light oil

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Light oil

Fig.24 Time change of the heating value of the reformed gas and the residual carbon content in ash during the 90 days continuous operation

Table 1 Energy balance of the commercial plant

B. Medium Calorific Gas Production (HyPR-MEET) The STAR-MEET system is one of air-blown gasification systems, so the nitrogen contained in air will be mixed into the fuel gas which lowers the heating value of the fuel gas down to about 4MJ/Nm3. Thus the use of this low calorific gas is limited only to power generation. In order to avoid nitrogen mixing into the fuel gas, the HyPR-MEET system are developed. The HyPR-MEET system is aiming at gasifying solid wastes including biomass resources with high temperature steam heated up to about 1000-1300C by using a high temperature heat exchanger and at producing medium calorific gases whose main components are H2 and CO. The produced medium calorific gas is used for driving a gas engine generator, used as a fuel for molten carbonate type fuel cells or used as a feed stock gas for extracting hydrogen. The flow diagram and a photograph of the demonstration plant of the HyPR-MEET are shown in Figs. 25 and 26, respectively. Produced gas compositions from wood chips as a function of the steam/carbon ratio is shown in Fig.27, where we can see that hydrogen-rich (more than 50%) medium calorific gas was produced.

Fig25. System flow of the HyPR-MEET system Fig.26 Photograph of the demonstration plant of the HyPR-MEET system (50kg/hour) Fig.27 Gas composition obtained from wood chip gasification

V. SUMMARY The main feature of these technologies introduced in this

paper is that we can constitute the optimum treatment scheme fitting to the property of biomass/wastes, amount of biomass/wastes and energy requirement. For high moisture content and/or mixed wastes or biomass resources, the hydrothermal treatment (RRS) to crush, dry and deodorize biomass/wastes to produce high quality fertilizer or fuel is most appropriate. For dry or semi-dry solid wastes, the STAR-

Items Units Values

Chicken Manure LHV kcal/kg 2465

Feed Rate of Chicken Manure kg/h 90.0

Reformed Gas LHV kcal/Nm3 1,050

Flow Rate of Reformed gas Nm3/h 156

Cold gas efficiency % 73.8

Carbon conversion efficency % 96.6

Gross thermal efficiency % 21.8

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MEET system can be applied to produce low calorific gases for power generation using duel-fueled diesel engines, and the HyPR-MEET system can be applied to produce hydrogen-rich medium calorific gas. For waste plastics and oils, liquefaction technology is best fit to produce light oil or kerosene equivalent fuel oils. The dry BDF production technology can be utilized for small to large scale applications of BDF production from plant oil and waste cooking oil. These technologies are completely different from existent waste treatment technologies based on land-filling or incineration, and are aiming at producing salable products from unutilized resources. Therefore, even in developing countries where waste treatment cost is very low, these technologies are quite effective to solve the waste treatment problem as well as to contribute for mitigation of global warming and are expected to disseminate all over the world in the near future.

Successful Localization of Japanese Waste-to-Energy Technologies in

Developing Countries throughDeveloping Countries through Student ExchangeStudent Exchange

i hikKunio Yoshikawa

ProfessorFrontier Research CenterFrontier Research Center

Tokyo Institute of TechnologyJapanJapan

Condition for Profitable Waste-to-Product Business

Income from + Income from ＞Labor cost + Utility cost + Capital cost

Business

Income fromWaste Treatment

+ Selling Product＞Labor cost + Utility cost + Capital cost

Tokyo Institute of Technology is actively conducting R&DTokyo Institute of Technology is actively conducting R&Defforts to convert unutilized resources such as wastes andbiomass into high value-added energy resources (coal-likebiomass into high value-added energy resources (coal-likesolid fuel, natural gas-like gaseous fuel, petroleum-like liquidfuel hydrogen and electricity) and is applying R&Dfuel, hydrogen and electricity) and is applying R&Dachievements to various fields all over the world.

Number of students in my laboratoryJapan (10) China (11) Indonesia (5) Thailand (4)Japan (10) , China (11), Indonesia (5), Thailand (4),Korea (1), Mongolia (1), Sri Lanka (1), Tajikistan (1)

Solid Fuel Production

Solid Fuel Production

M i i l S lid W H i l WMunicipal Solid Waste Hospital Waste

Animal Manure Sewage Sludge

Hydrothermal Treatmenty

Dry Product

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BoilerFuel

Steam input200℃,2MPa

MotorReactor

natural drying

ProductMotor •Furnace

•Boiler

Water Treatment Condenser

WaterClean Water •Cement Kiln

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① MSW Treatment

Commercial Hydrothermal TreatmentCommercial Hydrothermal Treatment Facility (Hospital Wastes)

MSW TreatmentPhysical Appearance

Raw MSW

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Application of Waste-to-FuelIn Cement Production LineIn Cement Production Line

pp

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Mixer Bunker

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MSW = Municipal Solid Wasteproduct out

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Chlorine Conversion by Hydrothermal ProcessChlorine Conversion by Hydrothermal ProcessC o e Co ve s o by yd o e ocessC o e Co ve s o by yd o e ocess

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•• Organic chlorine is reducing while inorganic chlorine is increasingOrganic chlorine is reducing while inorganic chlorine is increasing

Organic Chlorine Inorganic Chlorine

•• Very less chlorine in condensed water; therefore, inorganic chlorine, instead of Very less chlorine in condensed water; therefore, inorganic chlorine, instead of HClHCl, was formed by hydrothermal process , was formed by hydrothermal process inorganic chlorine washing!inorganic chlorine washing!

ChlorineChlorine RemovalRemoval by Washingby WashingChlorine Chlorine RemovalRemoval by Washingby Washing

1.4%

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e Amou

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Before Washing 1 432% 1 452% 1 413%

1:1 1:2 1:4

B i l t t ti f 1 1 2 ti l d hi

Before Washing 1.432% 1.452% 1.413%1st Washing 0.321% 0.143% 0.053%2nd Washing 0.106% 0.062% 0.043%

By using sample to water ratio of 1:1, 2 times recycled washing was adequate to reduce the chlorine content down to 1060 ppm

PhD Thesis

Co combustion Characteristics of HydrothermallyCo-combustion Characteristics of Hydrothermally Treated Municipal Solid Waste with Coal

D M i M h (I di 2010)Dr. Marisamy Muthuraman (India, 2010)

Dechlorination of Municipal Solid Waste in Lower T t b E l i M di PTemperature by Employing Medium Pressure

Hydrothermal Process to Produce Alternative Solid Fuel

Dr. Pandji Prawisudha (Indonesia, 2011)

② Sewage Sludge Treatment

Pilot Plant Testing (1.5m3 Reactor)Sludge supply

Steam supply from boiler

Steam discharge to deodorizer

RReactor

Silencer Product discharge

Rotor

Sewage sludge treatmentg g

HydrothermalHydrothermal treatment Water

content%85%

Water content 80%

MechanicaldehydrationFast natural dryingy g

（24 hours）

Water content 55%Water content 10～20% Separated water

Dehydration performance%

]

y pThe solid products were dehydrated by a screw press machine.

ent [

wt%

80

100

re c

onte

base

40

60

Moi

stu

Wet

0

20

0Sewagesludge

403 413 423 443

Temperature at the bottom of the reactor [K]

The dehydration performance was improved by steam over the temperature ofThe change of moisture content with temperature

Temperature at the bottom of the reactor [K]

The dehydration performance was improved by steam over the temperature of 423K.

Drying performanceThe sample after dehydration was dried by air blow.

100

[wt%

]

80

100Raw sewage sludge Solid products after dehydration

cont

ent

se 40

60

oist

ure

cW

et b

as

0

20

Mo

Ti [h ]

00 10 20 30 40 50 60

The drying time of solid products was shorter than sewage sludge

Time [hour]The change of moisture content with time

The drying time of solid products was shorter than sewage sludge.

Change of Existence Form of Water in Sewage Sludge

“Free water”：Mechanical removal is possible

“B d d t ” M h i l l i diffi lt“Bounded water”：Mechanical removal is difficult（Water in cells, etc.）

Dehydration performance improves by the hydrothermal treatment due to flow out of bounded water in cells to outer surface

Commercial Plant of Hydrothermal T f S Sl dTreatment of Sewage Sludge

(100tons/day)(100tons/day)(China, Inner Mongolia）

A Joint Research with a Chinese CompanyA Joint Research with a Chinese Company Employing Our Chinese Graduate

Reactor (7.8m3, 3MPa) ( , )

Coal Fired Boiler (2t/h 3MPa)Coal Fired Boiler (2t/h, 3MPa)

Plate and Frame Filter

Effects of the reaction temperature and time on the dehydration performancethe dehydration performance(reaction time=30minutes)

80

100

after

%）

60

ontent

ion（

%

20

40

sture Co

hydrati

0

20

0 30 60 90 120 150 180 210

Mois

De

0 30 60 90 120 150 180 210Reaction Tmeperature (℃)

Frame Filter HorizontalDecanterCentrifuge

2

Frame Filter Horizontal Decanter Centrifuge

Small Centrifuge(large‐scale reactor) small Centrifuge (small‐scale reactor)

PhD Thesis

Process Optimization of Hydrothermal Treatment ofProcess Optimization of Hydrothermal Treatment of Sewage Sludge for Solid Fuel Production

D Ji Jili (Chi 2011)Dr. Jiang Jili (China, 2011)

Save Japan Project

26

1 Cutting sunflower culture

1 Initial Cs concentration:(1)1. Initial Cs concentration:(1) 0,10,100ppm. (2) 50ppm.

2. Room temperature: 298K.3. Culture time: 4 days.

Experimental ApparatusExperimental ApparatusLaboratory Autoclave

500 ml20 MPa300 0C

Sample& ProductSample& Product Water 2 times of sample; at set temp ; holdingWater 2 times of sample; at set temp.; holding 30mins; exhaust steam at 443K; sampling at 343K343K.

Result at 220℃

Solid

StHydro-th l

(10%)

Stem uptake(100%)

thermal treatment(100%)

Loss(20%) (100%) (100%)

Liquid(70%)

Cs content in solid(dry)

1g dry solid Cs content

1 0001.100 1.200 1.300

y solid)

0 5000.600 0.700 0.800 0.900 1.000

mg Cs/g

dry

No washing

0 0000.100 0.200 0.300 0.400 0.500

centra

on(m

Washed

0.000 373 423 473 523 Co

nc

Temperature(K)

Liquid Fuel Production

① Oil Production from Waste Plastics

Flow of oil production from waste plasticsAgitator

Waste plastics

Flow of oil production from waste plastics


Screw hopper

Cooler煙突



Off-gas burnerOil/water separation

No.1 Condensor


Residue recovery

Oil recovery

Burner

Oil pump000000000000000000OOOOOOOOOO

Oil recovery

Oil pump

Controller

OFF

ON

OFF

ON

OFF

ON

OFF

ON

OFF

OFF

Oil tank

F FFOil tank

Carbon number distributionCarbon number distribution

25.0

30.0

20.0

C t l ti f iＷＴ

15.0


ＷＴ／％

5.0

10.0

0.0

Carbon number

Pyrolytic Reformed Oil

Commercial Plant for Metal and Oil Recovery from Waste Mobile Phones and Computersfrom Waste Mobile Phones and Computers

（500kg/hour）

Recycling of E-WasteRecycling of E Waste

Recycled oilRecycled oil

Carbonized solid

MetalWhen E-wastes such as cellular phones and PC board are process by this technology we can recover rare metalsprocess by this technology, we can recover rare metals together with oil.

Experimental Facilityp y1

N2

2 4 3 72

533

986

98

(1) Feeder (2) Pyrolyzer (3) Alumina balls (4)(1) Feeder, (2) Pyrolyzer, (3) Alumina balls, (4) Reformer, (5) Catalyst, (6) Condenser, (7) Micro GC-TCD, (8) Condensate Sampler, (9) Gas scrubbing bottles

Effect of the ReformingEffect of the Reforming Temperature (PE)Temperature (PE)

② Emulsion Fuel Combustion

Photomicrograph of emulsion fuel

Manufacturing condition Manufacturing condition

Bunker A Bunker A 9090％％

Microscopical water has been dispersed in Bunker A

Water Water 1010％％

※Manufacture by※Manufacture by our emulsion fuel our emulsion fuel manufacturing equipmentmanufacturing equipment

Measurement magnification：200times

manufacturing equipment.manufacturing equipment.

Production of emulsified fuel P

Injector Mixer BurnerPThe fuel supply unit

Emulsified FuelINV

Witho t anoil

FIA

Without any Surface Active

AgentsP

The installation unit on burner

Agents

water

INV

FI

oil Emulsified Fuel

WaterFIA

injector Line－mixer

Principle of Emulsified Fuel ~Behavior of droplets~~Behavior of droplets~

puffingwater oil

Vaporization of the water phase

puffing

Microexplosion

・Decrease of combustion gas temperature

Vaporization of the water phase

・ Suppression of high-temperature regionThermal NOx

Microexplosion

D f b i i・ Decrease of burning timeDust

ST1500 Boiler

Injector line-mixer

Water

Injector line mixer

Boiler

Control Unit Oil

Max. evaporation capacity: 1500kg/h

Type: Multi-piping flow-through

BurnerBurner

Type: Forced draft hydraulic pressure

Ignition: High voltage electric sparkg g g p

Experimental Result (Emissions)

Experimental Result (Thermal Efficiency)

Thermal Eff.＝Amount of heat transferred to steam／Thermal input of heavy fuel oil A (％)

Commercial Operation at the Heating Water Boiler in Hokkaido JapanHokkaido Japan

Boiler

Device used for P d i f l ifi d f lProduction of emulsified fuel

Spa Facilities in Hokkayido Japany p

Energy Saving 18A

1214 16 18

heav

y oi

l A[L

/t]

68

10 12

ptio

n of

hon

wat

er

02 4 6

Con

sum

ppe

r to Heavy Oil A

Emulsified Fuel

0 0 50 100 150

C

Amount of supplied water [t/d]

Effect on Boiler Maintenance

Before Maintenance After Maintenance

Hospital Boiler in BangkokHospital Boiler in BangkokBurner Bunker Oil BurnerBurner Bunker Oil BurnerBurner Type Pressure Jet,

Pressure AtomizingIgnition type Spark IgnintionControl PLC Controler

Boiler Type Fire tubeConsumption of fuel

amount100 lites/hr

Pressure of produced steam 5 kg/cm2p g

maximum evaporation capacity

5,000 kg/hr

Heat transfer area 63.28 m2

λ=1.7

λ 1 50.092

0.093

0.094

oil A

per

n [kg/kg]

λ=1.5

λ=1.30.089

0.090

0.091

on of H

eavy

m produ

ction

OriginalState

λ=1.3 λ=1.3

0.086

0.087

0.088

Consum

ptio

one kg steam

0 5 10 15 20 oWater Contet %

8 0λ=1.3 λ=1.3

6.0

7.0

8.0

vy oil [%

]

λ=1.33.0

4.0

5.0

saving he

av

λ=1.7

λ=1.5

0.0

1.0

2.0

Percen

t

0 5 10 15 20

Water Contet %

12t/day Commercial Boiler12t/day Commercial Boiler(Chang Beer Factory, Thailand)(Chang Beer Factory, Thailand)

Gaseous Fuel Production and Power Generation Technologies

P l i ifi tiPyrolysis gasification

C HbO → Gas + Tar + CharCa HbOc Gas + Tar + Char

• Tar leads to fouling when it becomes saturated.

• Condensing and depositing of tar lead to more frequent maintenance and repair ofmaintenance and repair of especially gas cleaning equipment and resultantly l l ilower plant capacity factors.

Chemical methods Physical methodsChemical methods Physical methods

To destroy tar or to convert tar

Only remove the tartar

• Use of catalytic bed materials

• Cyclone• Filtersmaterials

• Gasifier design• Filters• Electrostatic

precipitators• Selection of the operating conditions

Pressure

precipitators• Scrubber (absorber)

Pressure TemperatureEquivalence ratio (ER)

• Adsorber

The physical tar removal q ( )• Thermal cracking

Catalytic cracking

The physical tar removal method is proven to be technically and

• Catalytic cracking• Plasma reactor

yeconomically attractive approach for gas cleaning

Gasification/Reforming system

ガス化室

投入口

Gasification

Ash

ガス化室

投入口

Gasification

Ash

改質ガス改質ガスReformed Gas改質ガス改質ガスReformed GasReformed Gas

ガス化室

熱分解ガス

chamber

PyrolysisGas

ガス化室

熱分解ガス

chamber

PyrolysisGas

熱分解ガス熱分解ガスPyrolysis Gas熱分解ガス熱分解ガスPyrolysis GasPyrolysis Gas

予熱層、乾燥層

元層

De-volatilization zone

Drying zone

予熱層、乾燥層

元層

De-volatilization zone

Drying zone 高温水蒸気/空気

ペブル床

高温水蒸気/空気

ペブル床

High temperature Steam/Air

Pebble Bed


ペブル床


ペブル床


Pebble Bed


Pebble Bed

酸化層

還元層

Oxidation zone

Gasification zone

酸化層

還元層

Oxidation zone

Gasification zone

酸化層

灰層

灰出口

点火装置

Ash

Ash zone

Oxidation zone

Igniter

酸化層

灰層

灰出口

点火装置

Ash

Ash zone

Oxidation zone

IgniterCCnnHHmm + nH+ nH22O O →→nCOnCO + (n++ (n+m/2m/2)H)H22

C H ( /2 /4)O CO /2H O

CCnnHHmm + nH+ nH22O O →→nCOnCO + (n++ (n+m/2m/2)H)H22

C H ( /2 /4)O CO /2H O


C H ( /2 /4)O CO /2H O


C H ( /2 /4)O CO /2H O灰出口

空気(600℃)

Ash

High temperature air

灰出口

空気(600℃)

Ash

High temperature air

Gasifier Reformer

CCnnHHmm + + ((nn/2+m/4)/2+m/4)OO22 →→nCOnCO + + m/2m/2HH22OOCCnnHHmm + + ((nn/2+m/4)/2+m/4)OO22 →→nCOnCO + + m/2m/2HH22OOCCnnHHmm + + ((nn/2+m/4)/2+m/4)OO22 →→nCOnCO + + m/2m/2HH22OOCCnnHHmm + + ((nn/2+m/4)/2+m/4)OO22 →→nCOnCO + + m/2m/2HH22OO

Gasifier Reformer

STAR-MEET System

Exhaust gas

Clean gasScrubber

Electricity

R t

Reformed gasFuel gas

Air

Wastes SteamGenerator Regenerator

Burner Recuperator

Exhaustgas

P l

Steam/Air(1000C) Reformed

gas

Airgas

Steam

イメージを表示できません。メモリ不足のためにイメージを開くことができないか、イメージが破損している可能性があります。コンピュータを再起動して再度ファイルを開いてください。それでも赤い x が表示される場合は、イメージを削除して挿入してください。

PyrolyzerPyrolysis

gas

BoilerReformed

gasイメージを表示できません。メモリ不足のためにイメージを開くことができないか、イメージが破損している可能性があります。コンピュータを再起動して再度ファイルを開いてください。それでも赤い x が表示される場合は、イメージを削除して挿入してください。

Reformer

g

WaterReformer

Ash 600C air

Dual-fueled Diesel Engine

Li h il

Fuel gas 40 800

g

Light oilAir

Exh. gas 30

35

600

700

N

20

25

ncy

[%]

400

500

NOｘEmis

15

20

l Effi

cien

300

400 sion

[ppm

5

10

Ther

mal

100

200

m]


00 20 40 60 80 100

0

NOx

Fuel Gas Rate [%]

Outline of the commercial facility

Chicken Manure Dryer Unit

Use of Chicken Body Heat Electric power Chicken Houseand Excess Heat Energy

(Water Content 70% → 15%）

Electric power → Chicken House Thermal energy → Chicken Manure Dryer

Heater aid

This plant was successfully operated for 90days continuous operation, in May 2007.operation, in May 2007.

Commercial updraft gasification system• Tar removal system consists of

1 Reformer1. Reformer

2. Water scrubber

3. Activated carbon adsorber

Performance of reformer, scrubber and adsorber

Gasifier Reformer Scrubber Adsorber

2.0

2.5

3 ) 0.10

0.12

3 )

Exit of gasifierExit of refomerInlet of scrubber

1.5

2.0

tion

(g/m

3

0 06

0.08

tion

(g/m

3

Exit of scrubberExit of adsorber

1.0

once

ntra

t

0.04

0.06on

cent

rat

0.0

0.5 Co

0.00

0.02Co

PhD Thesis

Effects of chemical and physical methods on tarEffects of chemical and physical methods on tar elimination in biomass gasification for practical

system designsystem designDr.Thana PHUPHUAKRAT (Thailand, 2010)

Joint Project with CMUJoint Project with CMU

Joint Research with Tar group member:

Asst. Prof. Chatchawan ChaichanaDepartment of Mechanical Engineering

Anchan Paethanom

Department of Mechanical Engineering, Chiangmai University, Thailand

MasatakaKobayashiSh t N k hJuly – October 2011 Shota Nakahara

Joint Project with CMUJoint Project with CMU

Capacity: 25 - 30 kW-thermal

production of useful fuels and electricity from...

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