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1.
《能源学会志》2019,92(6):1647-1657
This work primarily investigated the pyrolysis of post-consumer mixed plastic wastes during slow pyrolysis (non-isothermal) in a batch reactor to assess the effect of different heating rates on the product yield and its composition. The effect of residence time during fast pyrolysis (Isothermal) in Pyro-GC was also investigated. Initially, TG analysis was performed to investigate the degradation temperature range at different heating rates of 5, 10, 20 and 40 °C/min. Two different heating rates of 10 and 20 °C/min were selected for examining the effect on products such as oil and gases (H2, CO, CO2 and C1-C6 hydrocarbons) during slow pyrolysis. The oil obtained at higher heating rate had higher density (0.743 kg/m3) while the amount of residue decreased with the increase in heating rate. Also, the effect of residence time during fast pyrolysis was investigated using Pyro-GC at 500 °C for the product formation. It was observed that an optimum residence time of 10sec was favourable for the higher production of lower hydrocarbons (C1-C3) and less production of heavier hydrocarbons (C6). This work represents the combined analysis of fast and slow pyrolysis and their impact on the product yield. Also, the effect of heating rate on non-isothermal condition and the effect of the residence time of volatiles in isothermal condition was analysed and reported. 相似文献
2.
《能源学会志》2020,93(3):1148-1162
The present study addresses pyrolysis behaviour and potential of Samanea saman seeds (SS) towards its bioenergy potential using thermogravimetric analyzer and in a cylindrical pyrolyzer (semi-batch reactor). Pyrolysis kinetic behaviour of biomass was carried out using Kissinger, Distributed Activation Energy Model (DAEM) and Miura-Maki-Integral method (MMI) while thermal pyrolysis was carried out in a cylindrical shaped semi-batch reactor. Kinetic results confirmed that the average activation energy was found 118.24 kJ mol−1, 168.70 kJ mol−1, and 97.87 kJ mol−1 for Kissinger, DAEM, and MMI model respectively. Further, thermal pyrolysis of SS biomass yielded 44.20 wt% yield of pyrolytic liquid (31.20 wt% pyrolytic oil/organic oil and 13 wt% aqueous fraction). Characterization results of pyrolytic oil showed the presence of higher viscosity (86.01 cSt), higher oxygen content (33.11%), and lower ash content (0.46 wt%) and gross heating value. FTIR analysis confirmed mainly the presence of aromatics, acid, alkene, water, and protein impurities. Gas Chromatography (GC) results declared, an increase in hydrocarbon and hydrogen gas with an increase in temperature while reduced the generation of CO and CO2. Further, GC-MS analysis of pyrolytic oil revealed the presence of higher acids (19.46%), phenols (11.01%) ethers (11.12%) and ester (7.33%) which is a potent source of oxygenated compounds. Characterization results of biochar showed the presence of higher gross heating value (23.14 MJ kg), carbon content (62.66%), volatile matter (34.15%) and lower moisture (5.14%) and BET surface area (8.20 m2 g−1). Combining these results, it can be suggested that SS biomass has the potential to produce renewable fuel and chemicals, while biochar can be used for various applications. 相似文献
3.
《能源学会志》2020,93(5):2033-2043
The present study deals with the optimization of process parameters and thermocatalytic pyrolysis of Cascabela thevetia (CT) seeds in a semi-batch cylindrical-shaped reactor. Response surface methodology (RSM) was employed for the optimization of process variables, while commercial catalysts CaO and Al2O3 were used for catalytic pyrolysis. From results, it was concluded that 525 °C temperature, 75 °C min−1 heating rate, and 75 mL min−1 flow of nitrogen yielded maximum pyrolytic liquid (45.26 wt%) while with the attendance of catalysts at 20 wt% increased the yield of pyrolytic liquid (49.12 wt% and 46.87 wt% for CaO and Al2O3 respectively). Optimization outcomes displayed that linear and quadratic terms of utilized factors were more noteworthy while interaction effects between the factors were not significant. Further, characterization of pyrolytic oil established that utilization of catalysts expressively enhanced its properties by reducing viscosity and boosted the calorific value. FTIR examination of pyrolytic oil showed that the attendance of phenols, ethers, alcohols, ketones, alkanes, acids, etc., while 1H NMR results supported the FTIR results. GC-MS analysis showed a substantial reduction of phenols and oxygen-rich products and boost the development of alcohol and aldehydes in pyrolytic oil with the introduction of catalysts. These parameters indicate improved properties of pyrolytic oil, which intensified its bioenergy capabilities. 相似文献
4.
The products obtained by fast pyrolysis of biomass can be used as an energy source or chemical raw material. In this study, samples of hazelnut shells, tea bush, and hazelnut knot selected as waste biomass were from the cities of Trabzon and Rize in the Eastern Black Sea Region. Firstly, the waste biomass samples were granulated into four different particle sizes by milling and sieving operations. Fast pyrolysis of the samples with specific mixing rates was carried out in a fixed bed reactor. Additionally, 2 wt% vanadium (V) oxide (V2O5) was used as catalyst to maximize the yield of pyrolysis liquid products. The influence of temperature, heating rate, and particle size on fast pyrolysis yields under both catalytic and noncatalytic conditions were investigated and compared. While the amount of liquid product increased with the addition of catalyst, the amount of solid products decreased. It has been found that the temperature and heating rate parameters are very effective in liquid product yield. In all experiments, the maximum liquid yield was acquired at the same heating rate of 450°C min?1 and the temperature of 450°C with particle size of 0.5 to 1.0 mm. The maximum pyrolysis liquid (bio‐oil) was obtained with catalytic pyrolysis, and this value was 60.58 wt%. 相似文献
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6.
This work studies the influence of the operating conditions used in the pyrolysis of grape seeds on the morphology and textural properties of the chars resulting. Flash and conventional (283 K min−1 heating rate) pyrolysis have been used within a wide range of temperature (300–1000 °C). The effect of a pretreatment for oil extraction has also been studied. The porous structure of the chars was characterized by adsorption of N2 at 77 K, Ar at 77 K and 87 K, and CO2 at 273 K and mercury intrusion porosimetry. The morphology was analyzed by scanning electron microscopy. All the materials prepared revealed an essentially microporous structure, with a poor or even negligible contribution of mesopores. Increasing pyrolysis temperature led to higher specific surface areas and lower pore size. The highest specific surface area values occurred within 700–800 °C, reaching up to 500 m2 g−1 with pore sizes in the 0.4–1.1 nm range. No significant morphological changes were observed upon carbonization so that the resulting chars were granular materials of similar size than the starting grape seeds. The hollow core structure of the chars, with most of the material allocated at the periphery of the granules can help to overcome the mass transfer limitations of most common (solid or massive) granular activated carbons. The chars showed a good mechanical strength during attrition tests. These chars can be potential candidates for the preparation of granular carbons molecular sieve or activated carbons raw materials. 相似文献
7.
Mustafa Versan Kok Ece Topa 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(7):967-974
In this study, combustion and pyrolysis behavior of diesel and canola oil is investigated using thermal analysis techniques known as thermogravimetry (TG–DTG) and differential scanning calorimetry (DSC) at different heating rates. Reaction regions, peak temperatures, mass loss, heat flow rates, ignition temperatures, and specific heat of diesel and canola oil samples are determined using TG–DTG and DSC data. It was observed that as the heating rate of the reactions increased, peak temperatures of the reactions shift higher; implying that as the heating rate of the reactions increases the reactions lose their sensitivity. Five different kinetic methods were applied to determine combustion reaction parameters of the reactions. It was observed that averages of the activation energies of the samples are in the order of canola oil and diesel for different heating rates. 相似文献
8.
The black cumin seed cake (BCSC) is a by-product obtained from the black cumin seeds with cold pressing. This by-product can be utilized as a biomass feedstock for conversion to bio-oil with pyrolysis process. The BCSC samples were initially pyrolyzed on a lab-scale pyrolysis system at different values in the ranges of 300-800 °C and 0.050-0.300 L min−1 to determine the effects of operation temperature and N2 flow rate on the yields on products, respectively. Then, the bio-oil in the highest yield (wB = 44.37%) which was obtained at pyrolysis final temperature (450 °C) temperature, heating rate (35 °C min−1), particle size (dp > 850 ??m), and sweeping flow rate of 0.200 L min−1 was characterized by Fourier Transform infra-red (FT-IR) spectroscopy, gas chromatography/mass spectrometry (GC-MS) and column chromatography. Consequently, it was shown that the operating temperature and N2 gas flow rate parameters were effective on the product yields. Also, the important some physico-chemical properties of the pyrolytic oil obtained in high yield were determined as the calorific value of 38.48 MJ kg−1, the empirical formula of CH1.651O0.105N0.042S0.001, the rich chemical content containing many different chemical groups, and the density of 970.25 kg m−3, and the viscosity of 63.42 mm2 s−1. Based on the determined properties of the pyrolytic oil, it was decided that the use of pyrolytic oil derived from the BCSC may possible be for the production of the alternative liquid fuels and finely chemicals after the necessary improvements. 相似文献
9.
Recently, much research has been focused on liquid oil from biomass pyrolysis, which is considered as an alternative to conventional fossil fuels. This paper studies the effect of heating rate on both the yields and the chemical composition of the oil product obtained from pyrolysis of esparto which is the most important biomass in Morocco. The pyrolysis experiments of esparto was performed in a fixed bed reactor under argon atmosphere with different heating rate: 50, 150 and 250°C min?1. The maximum conversion of esparto in oil of pyrolysis was obtained with fast pyrolysis 68.5% at 550°C. The FT‐IR and 1H NMR analysis showed that the oil of pyrolysis formed principally by aliphatic compound. The analysis elemental showed that the H/C ratio increase and O/C decrease as the heating rate increase. The PCV improved slightly from 33.5 to 34.8 MJ kg?1. The oil obtained with higher heating rate has chemical properties similar to diesel that can be used with an economic and environmental advantage. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
10.
Fixed‐bed fast pyrolysis experiments have been conducted on a sample of cottonseed cake to determine the effects of pyrolysis temperature, heating rate and sweep gas flow rate on pyrolysis yields and chemical compositions of the product oil. The liquid products and the subfractions of pentane soluble part were characterized by elemental analysis, FT‐IR spectroscopy, 1H‐NMR spectroscopy and pentane subfraction was analysed by gas chromatography. The maximum oil yield of 34.8% was obtained at final temperature of 550°C with a heating rate of 700°C min?1 and nitrogen flow rate of 100 cm3 min?1. Chromatographic and spectroscopic studies on bio‐oil have shown that the oils obtained from cottonseed cake can be used as a renewable fuel and chemical feedstock. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
11.
Saeid Shahraki Mohsen Motahari-Nezhad 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2018,40(17):2037-2043
Pyrolysis is a thermal process where organic materials such as biomass and oil are decomposed and lighter materials such as gas, vapor, liquid products, and char are produced. The aim of this study was to investigate the pyrolysis behavior of sewage sludge in different operating conditions. Using a fixed bed, the influence of some important parameters such as pyrolysis temperature, heating rate, particle size, and N2 flow rate on product yields was studied. Results showed that with increase in temperature from 400 to 700°C, the char yield decreased from 30.1 to 7.50%, while the gas yield increased from 35.8 to 52.4%. The gas yield also increased from 46.9 to 49.1% as the heating rate increased from 20 to 60°C/s, while the oil yield increased from 45.2 to 46.8% as heating rate increased to 40°C/s and then the increase leveled off. 相似文献
12.
在TGA/SDTA851热重分析仪上,以N_2为载气,在气体流速为20 mL/min,升温速率分别为20℃/min、40℃/min、60℃/min和80℃/min,终温1100℃的条件下,进行了煤液化残渣的热解特性研究实验,得到了不同升温速率下神华煤液化残渣热解的TG和DTG曲线,表明神华煤液化残渣的热解是分两步进行的.在低温段主要是神华煤液化残渣中挥发性的气体溢出引起热解失重,在低温度段180~450℃,挥发分迅速释放;高温段则主要是一些高分子有机质的热解过程.此外,研究了粒径对热解特性的影响.研究发现,随着粒径的增加,残渣的最大挥发分释放速率逐渐减小,而最大挥发分释放速率对应的温度逐渐增加.利用Freeman-Carroll法得到煤液化残渣的动力学参数,为煤液化残渣的有效和经济利用提供理论依据. 相似文献
13.
Kinetic tests on pyrolysis of the mixture of waste automobile lubricating oil (WALO) and polystyrene (PS) were carried out with a thermogravimetric analysis (TGA) technique at a heating rate of 0.5 °C/min, 1.0 °C/min and 2.0 °C/min in a stirred batch reactor. WALO and PS were mainly decomposed 400–455 °C and 370–410 °C, respectively. The mixture of WALO and PS, however, was decomposed between 355 °C and 470 °C, and decomposition proceeded in two broad steps. The apparent activation energies for the pyrolysis of WALO/PS mixture were in the range of 176 kJ mol−1–369 kJ mol−1 at various conversions of 1–100%. The effect of heating rate on the product distribution was studied. The carbon number distribution of the produced oil shifted slightly to light hydrocarbons with a decrease in heating rate. The selectivity of hydrocarbons corresponding to the styrene monomer was high for the pyrolysis of the WALO/PS mixture. 相似文献
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15.
In this work, the co‐pyrolysis characteristics of oil shale with two typical coals, bitumite and lignite, and the co‐gasification characteristics of the mixture pyrolyzed fuels were studied via thermo‐gravimetric analysis. The individual fuels and mixture fuels were first pyrolysis in N2 atmosphere to specified temperature (450, 550, and 620 °C) at the heating rate of 20, 30 and 40 °C/min, respectively, and then maintained at the given temperature for 20 min before converted to CO2 ambient to conduct the CO2 gasification tests. The kinetic behavior and effects of both fuel types and pyrolysis temperature were investigated. The shoulder peak at around 550 °C observed in the derivative of weight loss derivative thermogravimetry analysis (DTG) curve during the pyrolysis of oil shale has confirmed the existence of specific reactions of oil shale at around 550 °C that leads to a sharp trough in the differential curves of co‐pyrolysis with coals and the unusual change in activation energies of gasification. In isothermal pyrolysis stage, oil shale lost its vast majority of organic matters at the temperature lower than 550 °C. The escape of pyrolysis gas and liquids in the coals is much harder than that in oil shale. The interaction between oil shale and bitumite was too weak to discriminate both in the pyrolysis and CO2 gasification process. The variation of the particle surface structure caused by the releasing of volatile gases is strongly affected by the reaction rate and temperature. Quick volatile decomposition and gas releasing lead to the increase of surface area, decrease of the average pore diameter as well as the uniformization of the pore structure, while the higher temperature results in the blockade and merging of fine pores. The two factors lead to the greatest mass loss rate in the pyrolyzed particles obtained at 550 °C in temperature programmed CO2 gasification stage. Two model‐free methods, Friedman method and Flynn–Wall–Ozawa method, were used to extract kinetic parameters from the experimentally determined pyrolyzed fuel conversions. The volatile contend has a significant influence on the fixed carbon conversion during the partially pyrolyzed particles' CO2 gasification. In this study, significant interactions existed in co‐thermal utilization, both pyrolysis and CO2 gasification, of oil shale and lignite. It is therefore surmised that co‐gasification of pyrolyzed lignite and oil shale may represent a feasible, practical route to high‐efficiency utilization of these fuels. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
16.
Xiangui Wang Yue Zhang Ling Dong Lixin Zhang Xiaoxiang Li Jinwei Jia Long He Xinqian Shu 《热科学学报(英文版)》2013,22(3):282-286
Based on thermogravimetric analysis, kinetic parameters of Shenhua coal, such as activation energy and frequency factor have been got from the TG / DTG results. It showed that activation energy is the smallest at the temperature from 850℃ to 930℃ with heating rate of 15℃·min-1 . Pyrolysis was further carried out on a fixed-bed reactor with different heating rate. The production of hydrogen has been studied in particular. It gave the highest hydrogen production at the heating rate of 15℃·min-1 . And it also found the increase of hydrogen production with the raise of temperature. Furthermore, catalytic pyrolysis of coal was done at adding 2% of transition-metal oxides to discover the impact of catalysts upon coal pyrolysis at heating rate of 15℃·min-1 . It indicated that both N-type and P-type oxide enhanced hydrogen production in coal pyrolysis. However, it showed that N-type oxide increased hydrogen production at medium temperatures, and P-type oxides improved hydrogen production at higher temperatures. 相似文献
17.
《能源学会志》2020,93(6):2456-2463
This work focuses on bitumen slow pyrolysis. Mass and energy yields of oil, solid and gas were obtained from pyrolysis experiments using a semi-batch reactor in a nitrogen atmosphere, under three non-isothermal conditions (maximum temperature: 450 °C, 500 °C and 550 °C). The effect of temperature on the product yields was discussed. The gas compositions were analysed using gas chromatography (GC) and the heating value of oil and solid residue was also measured. Using a thermo-gravimetric analyser, kinetic parameters were evaluated through Ozawa-Flynn-Wall (OFW) method. Results showed that oil yield is maximum at 500 °C (50%). Moreover, gas yield increased with increasing pyrolysis temperature from 18% to 36%. On the other hand, solid yield showed an opposite trend: it decreased from 39% to 32%. As regard energy yields, they showed a similar trend with the mass ones. H2, CH4, C2H4, C2H6 and C3H8 are the main components of the produced gas phase. It has been noticed that the recovery of bitumen to liquid oil through pyrolysis process had a great potential since the oil produced had high calorific value comparable with commercial fuels. 相似文献
18.
Slow, fast and flash pyrolysis of rapeseed 总被引:3,自引:0,他引:3
Pyrolysis experiments have been conducted on a sample of rapeseed to determine particularly the effects of pyrolysis temperature, heating rate, particle size and sweep gas flow rate on the pyrolysis product yields and their chemical compositions. The maximum oil yield of 73% was obtained at the final pyrolysis temperature of 550–600 °C, particle size range of +0.6–1.25 mm, and sweep gas flow rate of 100 cm3min−1 (N2) at flash pyrolysis conditions in tubular transport reactor. Chromatographic and spectroscopic studies on the pyrolytic oil showed that the oil obtained from rapeseed can be used as a renewable fuel and chemical feedstock. 相似文献
19.
Fixed-bed slow pyrolysis experiments have been conducted on a sample of safflower seed to determine particularly the effects of pyrolysis temperature, heating rate, particle size and sweep gas flow rate on the pyrolysis product yields and their chemical compositions. The maximum oil yield of 44% was obtained at the final pyrolysis temperature of 500°C, particle size range of +0.425–1.25 mm, with heating rate of 5°C min−1 and sweep gas (N2) flow rate of 100 cm3 min−1 in a fixed-bed lab-scale reactor. Chromatographic and spectroscopic studies on the pyrolytic oil showed that the oil obtained from safflower seed can be used as a renewable fuel and chemical feedstock with a calorific value of 41.0 MJ/kg and empirical formula of CH1.92O0.11N0.02. 相似文献
20.
Hamayoun Mahmood Naveed Ramzan Muhammad Moniruzzaman Tanveer Iqbal Mohsin Ali Kazmi 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2019,41(14):1690-1700
A primitive element for the development of sustainable pyrolysis processes is the study of thermal degradation kinetics of lignocellulosic waste materials for optimal energy conversion. The study presented here was conducted to predict and compare the optimal kinetic parameters for pyrolysis of various lignocellulosic biomass such as wood sawdust, bagasse, rice husk, etc., under both isothermal and non-isothermal conditions. The pyrolysis was simulated over the temperature range of 500–2400 K for isothermal process and for heating rate range of 25–165 K/s under non-isothermal conditions to assess the maximum pyrolysis rate of virgin biomass in both cases. Results revealed that by increasing the temperature, the pyrolysis rate was enhanced. However, after a certain higher temperature, the pyrolysis rate was diminished which could be due to the destruction of the active sites of char. Conversely, a decrease in the optimum pyrolysis rate was noted with increasing reaction order of the virgin biomass. Although each lignocellulosic material attained its maximum pyrolysis rate at the optimum conditions of 1071 K and 31 K/s for isothermal and non-isothermal conditions, respectively, but under these conditions, only wood sawdust exhibited complete thermal utilization and achieved final concentrations of 0.000154 and 0.001238 under non-isothermal and isothermal conditions, respectively. 相似文献