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Used tires as a raw material for the production of alternative fuels in

the WtL processes

K. Biernat1,2

1Automotive Industry Institute, Department of Fuels and Renewable Energy, 55 Jagiellonska Str., 03-301 Warsaw,POLAND;

2Institute for Ecology and Bioethics of CSWU, 1/3 Woycickiego Str. 01-938, Warsaw, POLAND.Contact details to author: [email protected], phone number: 48 22 7777225

Used tires might be a rich source of valuable energy and chemical products. These products could be received in the process of WtE and WtL by thermal decomposition of rubber in oxygen-deficient atmosphere. The gas products,

hydrocarbon oils and carbon black residue are obtained by waste tires pyrolysis. In operating systems (demonstration, pilotinstallations) pyrolysis is an intermediate stage leading to the energy use of rubber raw material. Tests of using pyrolysis

oil as a feedstock to produce fuels by hydrocracking processes was carried out, however there are only experimental or pilot installations. The recycling of tires by continuous pyrolysis process could lead to the obtaining of liquid energycarrier (heating liquids and gases) and technical carbon black. Thermo-gravimetric study was applied for determination

basic technological parameters for producing liquid energy carriers with particular attention in determining the fractionaland structural-group composition of pyrolysis products. In this area, thermogravimetric study of thermal decomposition ofshredded car and radial tires, including analyzing the chemical composition of gaseous decomposition products and

structural composition of liquid products, was carried out. The research results and analysis showed that it is possible to blend high-quality alternative fuels, including fuels for diesel and traction engines, with a properly compiled pyrolysis oil

distillate composition.

1. Used tires as a resource

Processing waste into alternative fuels, used directly or in order to produce electricity and heat is becoming increasingly preferred way to use energy characteristics of those waste, properly in the WtL processes of (Waste to Liquid) or WtE(Waste to Energy). The complex morphology and unstable composition of the waste substances, as well as formal andlegal requirements are the main cause of relatively small use of waste (including used tires) by the energy industry, particularly in the countries of Central and Eastern Europe. The legal requirements in many European countries allowed

energy recovery, if it meets the emissions, environmental, technological and social requirements.List of industrial plants, that can use alternative fuels, is contained in the relevant legislation, which gives the possibility of using these fuels in existing systems. There are following types listed:

• cement kilns

• lime kilns

• blast furnaces

• coke oven batteries

• rotary kilns for ores burning

• power and industrial boilersUnder current law, alternative fuels can be used in combustion or co-incineration processes at waste incineration

plants. Regulations clearly state, what is the input of alternative fuels for the relevant processes. Depending on whetherthe fuel will be used as the only material or undergo the co-incineration process, they must comply with the standardsspecified for a given emission. It should be remembered, that the emission standards for co-firing installations are

slightly lower than for combustion plants, and therefore meeting the threshold may be associated with somemodernization and technological investments. Co-incineration of non-hazardous waste in quantities of less than 1% of

the combusted fuel weight means not applying to such process the emission standards just like for co-firing process, butonly emission standards, such as for energy fuel combustion. In addition, co-firing will cause the need to change thestatus of the power plant, and it will change the status of waste products (fly ash and slag). These products havedifferent code marks and foremost it subjects to other development opportunities. The use of fly ash in construction islimited by standard PN-EN 450:2006 for the waste from the coal combustion. The use of such waste is also related tothe possession of relevant authorizations (waste from the combustion of used tires has i.a. heavy metals).

Index of modern methods of waste tires management is shown in Table 1.

Materials and processes for energy: communicating current research and technological developments (A. Méndez-Vilas, Ed.) ____________________________________________________________________________________________________

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Table 1. Methods of waste tires management [1]

Type Process Products

Phisical Re-use Barriers, covers

Retreading New tires

Granulation Asphalt additives, re-use in other products such as a layerunder-lining, playground and track surfaces

Thermal Co-incineration in cement kilnsand power boilers

Replacement of fossil fuels, energy

Special combustion Energy and steel for reuse

Pyrolysis Carbon black, pyrolysis oil and synthetic gas

Pyrolysis + gasification Carbon black, steel and synthetic gas

Gasification Steel, synthesis gas

Cryogenics Steel, rubbery granulate

Installations for the recovery or disposal of non-hazardous waste by using thermal processes have to be considered

for installations that may significantly affect the environment. Technical requirements for such a systems are also welldefined in the relevant legislation. Emission standards for co-incineration plants are related to such pollutants as:

• dust

• total organic carbon

• hydrogen chloride

• hydrogen fluoride

• sulfur dioxide

• nitrogen oxide and nitrogen dioxide

• carbon monoxideMeasurements of these emissions should be carried out continuously. In addition, concentrations of dioxins, furans

and heavy metals listed in the Regulations should be periodically measured. Emission levels for individual substancesare shown in table 2.

Table 2. Sample emission standards for power boilers of different thermal power [2]

Name of the

substance

Nominal thermal

power of plant

[MW]

Emission standards [mg/m3u]

C p Cw C

Total dust 50÷100 50 10 44

100÷300 30 10 27

>300 30 10 27

Sulfur dioxide

(SO2)50÷100 850 50 730

100÷300 200 50 178

>300 200 50 178 Nitrogen oxides(NO2)

50÷100 400 200 370

100÷300 200 200 200

>300 200 200 200

2. Pyrolysis processes of used tires

Gum is a rich source of energy and valuable chemical products, which can be recovered by thermal decomposition ofrubber without oxygen. This process has been known for many years as the process of pyrolysis. As a result of the

pyrolysis, obtained products are gas, hydrocarbon oils and charred residue. In existing installations (demonstration, pilot) pyrolysis is an intermediate stage leading to the energy use.

In solutions of pyrolytic processes, in the reactor tank can be placed whole tires, chopped tires or shredded tires withsimultaneous removal of metal weave elements. The implementation of the pyrolysis process usually involves heatingthe whole or cut tires, with the absence of oxygen, at a temperature from 450 to 750 oC. As a result of thermal


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decomposition are obtained generally two phases: solid and gas. Both of these phases can be subjected to further treatedin order to obtain more valuable products, such as gaseous or liquid energy carriers. Currently, in pyrolysis processesare commonly used reactors with a capacity of 2 to 6 Mg tires/h. There are also smaller reactors with a processingcapacity of tires in a row (1...2) Mg tires/h. In certain solutions, the reactors can be heated directly or in diaphragmatic

way, and structurally are divided into vertical or horizontal, or also with a mobile or fixed bed. Some authors indicatethe possibility for pyrolysis of tires in a fluidized form. Up to now, known tire pyrolysis process involves the

introduction of tires into the reactor, through the air lock preventing access the air to the reaction chamber. The processing time depends on the type reactor. Thus, in the turnover reactors the time is from 30 to 60 min, whereas instationary reactors the time may be extended up to 8 h. The effect of deep tires pyrolysis are: charred residue containingsmall quantity of volatile matter, and (3...5)% of sulfur and about 15% ash and a mixture of hydrocarbon gases. The

quantity of ash may be greater in the case of pyrolysis of tires containing silica. Pyrolysis residue containing mainlycarbon has a calorific value of about 28 MJ/kg and after magnetic separation of metal weave elements is used as a solid

alternative fuel. The gas phase is condensed partly to give a fraction type "pyrolytic oil" with a calorific value of about40 MJ/kg. Uncondensed hydrocarbon gases having a calorific value of 35 MJ/ kg are generally used with pyrolytic oilas an energy source for the reactor. There were conducted attempts to use of pyrolytic oil as a raw material for the fuel production by hydrocracking processes, but so far, there are basically only experimental or pilot installations. Processesof tire pyrolysis conversion in experimental or pilot scale were carried out using a reactor heated in diaphragmatic wayor in rotating reactors by companies: THIDE-PKA, Svedala, Karbon Produkt International and RAT; in the reactors,

type string feeder moving bed by companies: Traidec, Pyrocycling and Alcyon (Multipurpose blade); the rotary reactor,

heated directly by the company Basse Sambre-ERI in fixed-bed reactors by Nexus (fed batch) and company Terra(vertical reactor) and multideck reactors, moving bed reactors by NESSA.

In the field of the above processes, are ongoing research related to tire pyrolysis process with simultaneous attemptsof total use of pyrolytic products. New developed technologies are covered by many patents. All of these technologiesare based on direct pyrolysis reactors or with pre-heating, have heat exchangers and scrubbers and also magnetic metal

separators, allow the steam activation of residues and pyrolytic oil filtration and possible purification of the residue tothe form of semi-active carbon black. Process emissivity is about 2 kg/h SOx, 2 kg/h NOx, i 1 kg/h PM.

Tire pyrolysis processes are shown in Figures 1 and 2.

Fig. 1 Sample scheme of pyrolysis process [1] Fig. 2 Scheme of sample pyrolysis process with the synthesisgas feed to the boiler [1]

Most processes performing thermal treatment process of waste tires are carried out in a cyclic manner, which maycause less favorable value of EIOER ratio ("Energy Invested on Energy Returned"). According to the literature data itcan be concluded that technology enables the processing of used tires that are environmentally troublesome waste, is

not currently implemented on the industrial scale process, continuously. Tire recycling technology in a continuousrecycling process, in the pyrolysis process, can lead to the preparation of liquid fuels (gas and heating liquids) andcarbon black.

Most of technologies were described in patents, mainly American ones, i.a.: U.S Patents No: 4,084,521; 4,235,676;5,389,691; 5,720,232, 6,736,940 and: 3,787,292; 4,261,795, 4,347,119; 4,501,644; 5,198,018, 5,411,714; 5,523,060,5,589,599, 6,226,889; 6,398,825; 6,758,150. In both groups of patents that concern the same process and apparatus are

disclosed no material handling methods and disposal of pyrolitic products with a flexible screw conveyor, independentfrom the axis of the reactor and the stirrers in the outlet channel, allowing discharge of gas and condensate recovery.

One of the pyrolytic decomposition products, which after suitable processing can be used as the liquid energy carrier,

is an pyrolytic oil. Table 3 shows the comparison of the basic properties of diesel fuel with properties of crude oil, pyrolytic oil and distilled oil.


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Table 3. Comparison of diesel oil properties with pyrolytic oil from pyrolysis of tires (TPO) and distilled TPO [3]

Properties Diesel oil TPO crude TPO distilled

Density in 150C [kg/m3] 890 935 871

Kinematic viscosity in 4000C [mm2/s] 2 3,2 1,7

Calorific value [MJ/kg] 46,5 42,83 45,78

Ignition temperature [0C] 50 43 36

Self-ignition temperature [0C] 56 50 48

Sulfur content [%] 0,045 0,95 0,26

Ash content [%] 0,01 0,31 -

Residual carbon [%] 0,35 2,14 0,02

As can be seen from the data presented in Table 3, the properties of the distilled pyrolytic oil are as similar to thoseof diesel fuel, which may indicate the rationality of the tires pyrolysis process, including the processing of the liquid and

gaseous energy carriers.

3. Study on thermal treatment of waste tires.

The study was conducted in the determination of the fractional composition and structural and group composition of pyrolytic decomposition products of car tires, in model terms, in order to define the capabilities and basic parameters ofthe technological process for obtaining fluid (liquid or gas) energy carriers.

According to the developed and adopted program the research involved:1. Thermo gravimetric research on process of thermal decomposition of shredded tires – normal and radial.2. Exploration of the chemical composition of the gaseous decomposition products, and the structural

composition of the liquid products.3. Research on pyrolytic oil distillation process into fuel components.

3.1. Thermogravimetric research

The thermo gravimetric study was conducted for determining the temperature and mass parameters of the pyrolysis process and to estimate the enthalpy values at specified intervals of decomposition temperature.

Measurements were performed in the Motor Transport Institute in Warsaw, on the Simultaneous Thermal AnalyzerSTA 449 F3 Jupiter ® from Netzsch. In this analyzer, the samples (S and R) are arranged at equal measuring cells(Al2O3 crucible pots) symmetrically in a common oven, whose temperature is controlled independently of the change inthe samples properties during the measurement, according to predetermined temperature program. The temperature program assumes heating samples to a temperature of 500 °C and heating rate of 10 K/min. As the inert gas was used

argon (flow rate 20 ml/min.), while non-oxidizing atmosphere was nitrogen N2 flow of 50 ml/min.Thermal analyzer measured the temperature difference between the samples:

ΔTSR = TS – TR .When the analyzer's furnace is heated and system is thermally symmetrical, then to the both samples flows the same

heat flux, and the temperature difference is zero then. When the steady state was disturbed by the change in the sample,or if there was a thermal imbalance caused by the difference in heat capacity of the samples, in DSC measure there weretemperature differences, ΔTSR ≠ 0, proportional to the difference in heat flux to the sample and the reference sample

and then:ΔΦSR = -k·ΔTSR

k - proportionality constant having the nature of inverse of thermal resistanceThe result of the DSC measurement was carried out by DSC curves - dependence of the measured heat flow

differences from the time/temperature, TG - weight change curve and the DTG - the first derivative of the TG curve.

Before measurements, the test samples were washed with ethanol and then dried on absorbent paper and, already dry, placed overnight in a desiccator, and the research results are shown in Figures 3 and 4


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Fig. 3 Derivatogram of sample from used car tire

As it seen in Figure 3, the process of thermal decomposition, associated with loss of sample mass starts from thetemperature 367.9 °C., wherein the heavy weight changes of the sample are presented in the two compartmentsidentifiable, that is weight reduction of 27.56% in the temperature range (367.9 ... 425.1) °C and at 34.13% in thetemperature range (425.1 ... 486.0) °C. At the same time the process takes the form of an endothermic decomposition,

just as it shown in Figure 4.

Fig. 4 Enthalpy changes of thermal decomposition of the sample from used car tire

As is apparent from the curve, the thermal decomposition process carried out in a non-oxidizing atmosphere has anendothermic nature, from the temperature at 367.9 °C. Heat value is cumulatively 159 J/g and is necessary to generate

process, wherein in the temperature of 486.0 ° C, the process continues at the expense of the enthalpy values. Thismeans that the optimum values of temperature, which allows to operate the process with a gradual recovery of thefraction of gas and liquid is temperature of about 400 °C. Due to, specified in research, energy needs (159 J/g)necessary to maintain the process, the process of feeding the raw material should be done on a continuous basis, whichis designed to reduce the energy demand.

3.2. Building the model reactor.

Pyrolysis experiment was carried out under nitrogen atmosphere in a tubular reactor made of stainless steel. This reactorwas constructed for research purposes, as a reactor model. The tubular reactor (40 × Φ 1.1 cm) was used for pyrolysis ofshredded, used tires and was externally heated by electric furnace (Φ 31 × 9.5 cm) with adjustable temperature with athermo steam inside the bed. A line connecting the outlet with the reactor and cold trap was heated with heating tapes to

300 °C to avoid the condensation of the bio oil vapors. Experiments were carried out in a tubular reactor in order todefine the influence of pyrolysis temperature and intensity of natural gas on the performance of pyrolysis products.


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Experiments have been conducted using the 7 K/min-1

temperature increasing to a final temperature in the range(400...700) °C under a nitrogen atmosphere. The gas flow was adjusted in the range (50...400) cm 3 /min-1. Liquid products were collected in a trap at the temperature of 0 °C. They consisted of the oil phase, which was isolated andweighed. Eventual increases of carbon deposit can be determined by weight from gain of weight reactor. The gaseous

products can be analyzed on-line on GC with TCD/FID detectors with a 1ml loop attached to the "Valco" type valve,controlled automatically. In an ongoing study, pyrolysis gases were directed through shut-off valve to the

chromatography bottle, and then transferred to a GC chromatographic analysis. Liquid products were submitted forfurther analysis.

3.3. Analysis of gaseous products of thermal decomposition of the tire material.

Gaseous products of pyrolysis of used car tire samples were sent directly from the model reactor for GC chromatographwith TCD/FID detectors. As a result of analysis, it was obtained the basic composition of pyrolytic gas, divided onidentified as to type and content (% v/v) hydrocarbons, which composition is given in Table 4.

Table 4. Composition of gas products of used tires pyrolysis

No. Chemical compositionTest result

% v/v

1 Nitrogen 0,71

2 Oxygen below threshold3 Carbon dioxide 19,6

4 Carbon oxide 2,29

5 Hydrogen 10,1

6 Argon below threshold

7 Steam -

8 Hydrocarbons:

a) methane 22,5

b) ethen (ethylene) 7,73

c) ethan 6,02

d) propene (propylene) 5,98

e) propane 3,63

f) isobutane 7,23

g) n-butane 1,64

h) butene 0,55

i) isopentane 1,74

j) n-pentane 5,19

k) pentene 1,22

l) hexane 1,77

From the data in Table 4, results a preferred pyrolytic gas composition, because of the possibility of its energy use.The total content of methane and hydrogen is 33.6% v/v, which indicates a very high calorific value of the gas. Highcalorific value will be characterized a mixture of ethane, propane and butane, with total content reaches 18.52% v/v.Pyrolytic gas does not contain water vapor, but contains a certain amount, prone to polymerization, of unsaturatedhydrocarbon gas in the amount of 15.48% v/v, and a small amount of pentane vapor (small hexane vapor concentrations

haven't adverse effects). Hence, this gas should be directly used as energy source for the pyrolysis reactor. You can alsoconsider the evolution of the synthesis gas components for further processing into hydrocarbons - components ofalternative fuels.

3.4 Research on the properties of pyrolytic liquid oil and distillate.

Resulting pyrolytic oil in a model reactor and separated distillate was analyzed to assess basic normative properties,

together with normal distillation. As a result of these analyzes, carried out in accordance with the applicable standardsfor test methods, it was specified, for both oil and distillate, the basic characteristics that determine the suitability of thisoil (distillate) as an alternative fuel. Analysis results for liquid oil pyrolytic are shown in Table 5. Table 6 shows thecourse of the distillation carried out pyrolytic oil, and in Table 7 - the results of the analysis performed for the distillate,respectively, separated from the pyrolytic oil.


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Table 5. Basic properties of pyrolytic oil as alternative fuel

No. Properties Test method Test result

1 Density in temperature 15oC, kg/m3 PN-EN ISO 12185:2002 (A) 907,3

2 Calorific value, MJ/kg PN-C-04062:1986 (A) 40,92

3 Kinematic viscosity at 40oC, mm

2/s PN-EN ISO 3104:2004 (A) 2,56

4 Sulphur content, % (m/m) PN-EN ISO 20846:2006 0,58

5 Ignition emperature in closed cup, oC PN-EN ISO 2719:2007 (A) 1)

6 Ash residue, % (m/m) PN-EN ISO 6245:2008 (A) 0,010

A – methods accredited by the PCA (AB098)1)

– determination cannot be done, because at the lowest point at 25 oC, product is lighting up on the first

inclination filament

Table 6. Course of the distillation, carried out at a pressure of 760 mm Hg (normal), for pyrolytic oil

No. % v/v distil to the temperature [ºC]

1 Start of distillation 50,0

2 5 80,0

3 10 115,0

4 20 141,0

5 30 163,06 40 187,0

7 50 225,0

8 60 260,0

9 70 294,0

10 80 340,0

11 90 364,0

12 End of distillation 368,0

13 Distilled 94,0 % v/v

On the basis of the normal course of the distillation process, from the liquid pyrolytic oil was isolated light distillate

in boiling temperatures range from the start of distillation to 60% (v/v) distillation temperature, and this fraction were

analyzed in accordance with the requirements for liquid fuels. Results of the analysis are shown in Table 7.

Table 7. Basic propertied of light distillate of pyrolytic oil

No. Properties Test method Test result

1 Density in temperature 15oC, kg/m3 PN-EN ISO 12185:2002 (A) 779,8

2 Calorific value, MJ/kg PN-C-04062:1986 (A) 40,92

3 Ignition emperature in closed cup, oC PN-EN ISO 2719:2007 (A) 1)

4 Ash residue, % (m/m) PN-EN ISO 6245:2008 (A) 0,001

5 Sulphur content, % (m/m) PN-EN ISO 20846:2006 0,98

6 Kinematic viscosity at 40oC, mm2/s PN-EN ISO 3104:2004 (A) 2)

7 IR spectrum MB-MPS 020:2002 (A) Fig.5A – methods accredited by the PCA (AB098)1) – determination cannot be done, because at the lowest point at 25 oC, product is lighting up on the first inclination filament

2) – determination cannot be done in accordance with standard PN-EN ISO 3104:2004, laboratory does not have suchcapillary with such small capillary constant, and the resulting time is not in accordance with the requirements of thestandard. The result viscosity is about 0,55 mm2/s

As it can be seen from the presented results, the light fraction may be a component of alternative fuels for diesel

engine, but because of too bad, for these engines, rheological properties and ignition temperature, it cannot enforce acompliant fuel for those engines. Hence the conclusion is that the need to determine the self-ignition temperature of the

fractions that can be distillated from the liquid pyrolytic oil, to develop a formulation of the appropriate composition ofdistillate with proper cetane number or at least a ignitability pointer of those compositions.

3.5 The study of the structural composition of the liquid phase of pyrolytic oil distillate

The structural composition of the determined distillate was examined by removing the IR spectrum of the liquid phaseof distilled pyrolytic oil. The progress of spectra is shown in Figure 5. The IR spectrum analysis shows the nature

determination of the bonds, and thus also allowances to specify the mutual participation in the distillation of certaincompounds as bonds. From the course of the spectral lines is resulting that in the wave number range (3100... 3050) cm-1


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are observed both aliphatic and aromatic compounds with bonds of C=C type, wherein the concentration of these

compounds is relatively small. In the range of 2980 cm -1 to 2850 cm-1 are observed C-H bonds, characteristic foralkanes in the CH3 and CH2 groups, and tertiary carbons. Carbonyl bonds C=O, typical for aldehydes, esters andketones (oxygen derivatives) of low concentration are observed in the range of about 1700cm -1.

There was also a small concentration of C=C bonds, characteristic for alkenes in the wave number 1630 cm-1 andarenas (wave number 1600 cm-1). The presence of ester bonds and optionally also carbonyl bonds were found at a wave

number 1400 cm-1

. Small concentration of aromatic rings was observed in the wave number approximately 850 cm-1

,while the presence of the alkanes with chains above C4 in the area of 720 cm

-1. In summary, it should be noted that theuse of the composition of the pyrolytic oil distillate, resulting in specific process conditions, there are no

contraindications for the use of these components as a high-grade fuel components for diesel engines in stationaryoperating conditions, and even under traction conditions.

Fig. 5 IR spectrum for light pyrolytic oil distillate

Conclusions

The analysis of the process of thermal decomposition (light pyrolysis) of used tires, run on a model conditions,

supported by the results of research on process kinetics and analysis of decomposition products allows for the following

conclusions relevant to the technology of the process, namely:1. Due to the kinetics of the process and the possibility to obtain a positive energy balance, taking into account

the results of derivatographic research, it advantages to operate the process continuously.2.

It is necessary to perform calculations of the reactor efficiency with, respect to the speed of substrate feed process.

3.

An important part of the process should be design of separator, which accepts and adequately dispersesmaterial. It should be a separator that can equalize the pressure and prevents air from entering into the reactor.

4. Technological system should have a cooling system in the form of closed circuit of coolant (water), as it resultsfrom the process carried out in a model reactor.

5. It is necessary to specify time of stay of the material in the reactor. It should contain in the range of (30...45)min.

6.

For proper use of products of pyrolytic decomposition, taking into account the possibility of use gas fraction asthe process energy carrier, it would be beneficial to determine the possibility of further use of excess amounts

of process pyrolytic gas.7. It is possible to compose high-value alternative fuels, including diesel engines, traction engines, from the

properly compiled pyrolytic oil distillates. This will require an additional study, taking into account therequirements of these engines in the field of rheology, lubricity properties, and in the field of properties of theignition delay period.

References

[1] Heermann C. i in.: "Pyrolysis & Gasification of Waste. A Worldwide Technology and Business Review", Juniper ConsultancyServices Ltd, 2001;

[2] T. Pająk „Wybrane aspekty współspalania odpadów w instalacjach przemysłowych, VI Międzynarodowe Forum GospodarkiOdpadami (Some aspects of co-incineration in industrial plants, VI International Forum on Waste Management) Poznań, May-

June 2005, pages.341-352;

[3] J.Jesila, G.Nagarajan, S.Murugan „Distilled Tyre Pyrolisis Oil as an Alternative Fuel for CI Engine”


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[4] Technology Evaluation and Economic Analysis of Waste Tire Pyrolysis, Gasification, and Liquefaction, California

Environmental Protection Agency, March 2006;[5] C. Roy, H. Darmstadt, B. Benallal, A. Chaala, A.E. Schwardtfeger ł “Vacuum pyrolysis of used tires”

[6] Yang Yongrong, Chen Jizhong , Zhao Guibin „Technical Advance On The Pyrolysis of Used Tires in China” (Symposium„China – Japan International Academic Symposium Environmental Problem in Chinese Iron-Steelmaking Industries andEffective Technology Transfer”);


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