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Abstract Eupatorium adenophorum is used as the raw material to produce valuable pyrolysis products by microwave pyrolysis (MP). The influence of pyrolysis parameters (pyrolysis temperature, pyrolysis time and nitrogen flow rate) o...
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Abstract Eupatorium adenophorum is used as the raw material to produce valuable pyrolysis products by microwave pyrolysis (MP). The influence of pyrolysis parameters (pyrolysis temperature, pyrolysis time and nitrogen flow rate) on the yield of pyrolysis products is investigated to get the optimal pyrolysis condition. Eupatorium adenophorum is also conducted in the conventional pyrolysis (CP) to investigate the influence of heat mechanism on the generation process of pyrolysis products. A comparison of MP and CP indicates that MP produces more bio‐gas (48.14%), and less bio‐oil (26.35%) compared to CP. The less carboxylic acid and more phenol in bio‐oil of MP are observed in the condition of MP compared to CP, indicating that MP could upgrade the quality of bio‐oil. Bio‐gas of MP has larger content of H2 and syngas (H2 + CO) than those obtained from CP. The property of bio‐char from MP is better than that of CP in terms of heat value, oxygen content, and specific surface area, which could be utilized in the metallurgical industry.
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A full 2~3 experimental factorial design approach was applied to obtain a mathematical mdoel relating the total condensable effluents in slow pyrolysis of bagasse briquettes to three independent variables. These were apparent dens...
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A full 2~3 experimental factorial design approach was applied to obtain a mathematical mdoel relating the total condensable effluents in slow pyrolysis of bagasse briquettes to three independent variables. These were apparent density of pressed bagasse briquettes (231 and 371 kg/m~3), highest pyrolysis temeprature (400 and 450 deg C) and residence time at highest pyrolysis temeprature (0 and 30 min). Detailed data processing to obtain a model as well as the model's statistical evaluaiton are shown. The conclusions are that the studied response deepnds on all three factors, although it is believed that the particular conditions of the pyrolysis installation used could be the cause of the signficant result found for the residence time variable. It is inferred that measruable amounts of very low boiling organic compounds are present in the bagasse's liquid effluents. These volatile substances should require effluents' coolints. devices working at temepratures well below 0 deg C.
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Possible variants of gasoline pyrolysis intensification, i.e., implementation of the process with separation and reinjection of the ethane or propane formed into the pyrolysis retort for further conversions, and recirculation of b...
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Possible variants of gasoline pyrolysis intensification, i.e., implementation of the process with separation and reinjection of the ethane or propane formed into the pyrolysis retort for further conversions, and recirculation of both hydrocarbons simultaneously, i.e., joint gasoline, ethane, and propane pyrolysis, are studied. The yields of the target products (ethylene and propylene) in all three cases are compared with the yields of hydrocarbons in the industrial process without recirculation. The profit an enterprise can get by applying this method is calculated.
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Pyrolysis is an important thermochemical route to decompose lignocellulose biomass into biogas, bio-oil, and biochar, which can be then converted into value-added biofuels, chemicals, and biomaterials. Conventionally, the pyrolysi...
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Pyrolysis is an important thermochemical route to decompose lignocellulose biomass into biogas, bio-oil, and biochar, which can be then converted into value-added biofuels, chemicals, and biomaterials. Conventionally, the pyrolysis reaction is carried out under inert atmosphere. The quality of biocrudes and biochars from the conventional pyrolysis could significantly vary, depending on the types of feedstocks and reaction conditions. After intensive studies on the conventional biomass pyrolysis for decades, the external heat supply for the endothermic pyrolytic reactions is still one of the most important roadblocks to inhibit the scale-up and commercialization of biomass pyrolysis technologies. Different from the pyrolysis under inert gas atmosphere, autothermal pyrolysis tends to depolymerize the biomass (polymers) with restricted supply of oxygen/air, also called oxidative pyrolysis. The presence of oxygen in the pyrolyzer will induce the exothermic char-oxygen and/or volatile-oxygen reactions, thus in situ providing the heat for the primary thermal degradation of biomass and the subsequent secondary reactions. Besides the change in product distributions, the key advantage of autothermal pyrolysis is its self-sustainability in terms of heat supply and requirement, facilitating the ease of further scaling up. This review will thus mainly focus on the sum of the recent advances in autothermal pyrolysis and also discuss some innovative pathways for improving/adjusting the product quality.
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Abstract Pyrolysis property is an important safety issue for asphalt materials. It is important to study the asphalt pyrolysis properties for selecting flame-retarding technology to improve the fire safety of asphalt materials. Di...
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Abstract Pyrolysis property is an important safety issue for asphalt materials. It is important to study the asphalt pyrolysis properties for selecting flame-retarding technology to improve the fire safety of asphalt materials. Differential scanning calorimeter–thermogravimetry–Fourier-transform infrared spectroscopy was used to analyze the main pyrolysis temperature range, thermal effects, and emitted volatiles of saturates, aromatics, resins and asphaltenes (SARA) fractions. The microscopic morphology, the elemental compositions and their contents of each SARA fraction pyrolysis residues were tested by environmental scanning electron microscope–energy-dispersive spectrometer. The results indicate that main pyrolysis temperature range of SARA fractions is 250–550?°C, of which saturates have the lowest initial pyrolysis temperature, successively followed by aromatics, resins and asphaltenes. Also, SARA fraction pyrolysis processes are mainly endothermic reactions. The main volatiles in the pyrolysis of SARA fractions are alkanes and a small amount of CO, CO2 and SO2. Finally, the morphology and their elemental compositions of pyrolysis residues of SARA fractions are different. Among them, the proportion of O element is decreased from saturates to aromatics, resins and asphaltenes while the proportion of C is basically increased.
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Biomass energy has become the fourth largest energy source following coal, oil, and natural gas due to its abundantly available sources. At present, pyrolysis oil and biochar are the main products of biomass pyrolysis for applicat...
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Biomass energy has become the fourth largest energy source following coal, oil, and natural gas due to its abundantly available sources. At present, pyrolysis oil and biochar are the main products of biomass pyrolysis for applications. Despite this, biomass products still have an untapped potential that deserves further exploration. Research on biomass pyrolysis gas has progressed gradually and is reaching a commercial level through deeper research. It is possible to purify and decoke pyrolysis gas into different gaseous products according to demand, and its components can also be separated and extracted for other purposes. Therefore, biomass pyrolysis gas has a great deal of potential for development. This paper reviews the mechanism of biomass transformation into pyrolysis gas, equipment, the influence of process parameters, analysis methods, potential applications of pyrolysis gas, and ideas for future pyrolysis gas product upgrading.
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Plastic waste has been growing every year, and as a result, environmental concern has been a topic of much attention. Many properties of plastics, such as their lightweight, durability, and versatility, are significant factors in ...
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Plastic waste has been growing every year, and as a result, environmental concern has been a topic of much attention. Many properties of plastics, such as their lightweight, durability, and versatility, are significant factors in achieving sustainable development. The exponential increase of plastic production produces every year approximately 100 million tons of waste plastic, which could be converted into hydrocarbon fuels by employing a process appropriately called pyrolysis. Pyrolysis, which is thermal or catalytical, can be performed under different experimental conditions that affect the type and amount of product obtained. With the pyrolysis process, products can be obtained with high added value, such as fuel oils and feedstock for new products. In this study, magnesium silicate (MgO_(3)Si) and Cloisite 30B were used as catalysts for the decomposition of different plastics, and the results were compared with the zeolite catalyst. In the case of high-density polyethylene (HDPE), the oil yield with a zeolite catalyst was found to be 71%, whereas with MgO_(3)Si and Cloisite 30B, this was 68% and 67%, respectively. Zeolite produced better results in the decomposition of polypropylene (PP) compared to MgO_(3)Si and Cloisite 30B. Fourier-transform infrared spectroscopy (FTIR), and gas chromatography (GC) were conducted in this work. The spectra results for all samples were consistent and in the fuel range.
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Pyrolysis can realise the harmlessness, reduction and resource utilisation of petroleum sludge in a short period. In the present work, a tank bottom sludge (SSOS) and a landing sludge (SLOS) from Shengli Oilfield were used for exp...
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Pyrolysis can realise the harmlessness, reduction and resource utilisation of petroleum sludge in a short period. In the present work, a tank bottom sludge (SSOS) and a landing sludge (SLOS) from Shengli Oilfield were used for experimental research. Thermogravimetric testing is used to initially determine the optimal range of pyrolysis temperature. Pyrolysis experiments were performed in a tube furnace reactor. Pyrolysis products were collected and analysed separately. The char yield of SSOS and SLOS were 50% and 70%, respectively. Although there are differences in the oil content of the two types of petroleum sludge, the oil yield remained nearly the same, which were both between 7% and 8%. As the pyrolysis temperature was raised to 500 degrees C, the yield of each product did not change greatly while their composition had obvious changes. High temperature is more conducive to the production of small molecule products. Result showed that pyrolysis treatment of petroleum sludge can effectively recover energy materials in the form of pyrolysis gas and oil. The heating value of char is lower than that of petroleum sludge, which means that char is not suitable for direct use as fuel. Pyrolysis treatment also showed good curing effect on Cr, which reached 85%. However, the solidification effect decreased as pyrolysis temperature increasing. It is necessary to pay attention to the heavy metal contained in char as soil improver. The rich surface structure of char provides evidence to produce high value-added carbon materials.
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The pyrolysis of waste automotive engine oil was investigated using microwave energy as the heat source, and the yield and characteristics of the pyrolysis oils (i.e. elemental analysis, hydrocarbon composition, and potential fuel...
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The pyrolysis of waste automotive engine oil was investigated using microwave energy as the heat source, and the yield and characteristics of the pyrolysis oils (i.e. elemental analysis, hydrocarbon composition, and potential fuel properties) are presented and discussed. The microwave-heated pyrolysis generated an 88 wt.% yield of condensable pyrolysis oil with fuel properties (e.g. density, calorific value) comparable to traditional liquid transportation fuels derived from fossil fuel. Examination of the composition of the oils showed the formation of light aliphatic and aromatic hydrocarbons that could also be used as a chemical feedstock. The oil product showed significantly high recovery (90%) of the energy present in the waste oil, and is also relatively contaminant free with low levels of sulphur, oxygen, and toxic PAH compounds. The high yield of pyrolysis oil can be attributed to the unique heating mode and chemical environment present during microwave-heated pyrolysis. This study extends existing findings on the effects of pyrolysis process conditions on the overall yield and formation of the recovered oils, by demonstrating that feed injection rate, flow rate of purge-gas, and heating source influence the concentration and the molecular nature of the different hydrocarbons formed in the pyrolysis oils. The microwave-heated pyrolysis can be performed in a continuous operation, and the apparatus described which is fitted with magnetrons capable of delivering 5 kW of microwave power is capable of treating waste oil at a feed rate of 5 kg/h with a positive energy ratio of 8 (energy content of hydrocarbon products/electrical energy supplied for microwave heating) and a net energy output of 179,390 kj/h. Our results indicate that microwave-heated pyrolysis shows exceptional promise as a means for recycling and treating problematic waste oil.
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The CFD modeling for fast pyrolysis has previously focused on the major pyrolysis products; liquid, char and gas. This paper introduces a new approach to biomass pyrolysis; integrating a complex scheme of reactions including forma...
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The CFD modeling for fast pyrolysis has previously focused on the major pyrolysis products; liquid, char and gas. This paper introduces a new approach to biomass pyrolysis; integrating a complex scheme of reactions including formation of such components as levoglucosan. The 3-D simulation takes into account the complex breakdown of each biomass subcomponent, the fluid dynamics of the process as well as the heat and momentum transfer of three Eulerian phases. The pyrolysis products include reference species that reflects the composition of the bio oil, gas fraction and char fraction. A number of reactions are in addition applied to account for the thermal cracking of tar compounds and the final compositions are compared to experimental yields. The results show that the predicted pyrolysis products reflect the experimental yields satisfactorily, apart from the water content which is under predicted. Most importantly though, the approach is computationally feasible and it should be useful for future work.
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