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The depleting fossil fuels and anthropogenic climate change require involvement of renewable energy resources, including animal wastes. One of the effective, although less studied, ways of the cattle manure transformation to a convenient energy source is its microwave pyrolysis (MWP) into a combustible gas. The MWP of cattle manure was experimentally studied, using differential thermal analysis, scanning electron microscopy, BET surface measurement, and high-speed video recording. Spark discharges between inorganic centers with metallic or semiconductor properties in the MWP-treated manure were found responsible for the MW-radiation impact. It was experimentally shown that on course of thermal destruction, the absorption of microwave radiation by manure increases almost two times probably due to a change in the composition of carbon-containing compounds and the release of gases, tar vapors, and pyrogenic water. The MWP treatment provides fast and uniform heating of manure with its more complete volatilization, leaving only 34.5% wt. of carbonaceous residue compared to 42.7% in thermal pyrolysis. The MWP gas is of relatively high calorific value (21.08 MJ m−3) at low content of ballast gases, thus providing environmentally friendly manure transformation with a lesser greenhouse effect. [ABSTRACT FROM AUTHOR]

Abstract When high-temperature steam is used as a medium to pyrolyze organic-rich shale, water steam not only acts as heat transfer but also participates in the chemical reaction of organic matter pyrolysis, thus affecting the generation law and release characteristics of gas products. In this study, based on a long-distance reaction system of organic-rich shale pyrolysis via steam injection, the effects of steam temperature and reaction distance on gas product composition are analyzed in depth and compared with other pyrolysis processes. The advantages of organic-rich shale pyrolysis via steam injection are then evaluated. The volume concentration of hydrogen in the gas product obtained via the steam injection pyrolysis of organic-rich shale is the highest, which is more than 60%. The hydrogen content increases as the reaction distance is extended; however, the rate of increase changes gradually. Increasing the reaction distance from 800 to 4000 mm increases the hydrogen content from 34.91% to 69.68% and from 63.13% to 78.61% when the steam temperature is 500 °C and 555 °C, respectively. However, the higher the heat injection temperature, the smaller the reaction distance required to form a high concentration hydrogen pyrolysis environment (hydrogen concentration > 60%). When the steam pyrolysis temperature is increased from 500 °C to 555 °C, the reaction distance required to form a high concentration of hydrogen is reduced from 3800 to 800 mm. Compared with the direct retorting process, the volume concentration of hydrogen obtained from high-temperature steam pyrolysis of organic-rich shale is 8.82 and 10.72 times that of the commonly used Fushun and Kivite furnaces, respectively. The pyrolysis of organic-rich shale via steam injection is a pyrolysis process in a hydrogen-rich environment.

Despite policies to restrict the mixing of organic waste with other general waste and improve its separation at source, municipal solid waste still contains a high proportion of organic waste. The residual organic waste is generated as a by-product of the mechanical treatment of municipal solid waste (MSW) and is mainly disposed in landfills after composting. Its reuse and recovery status varies across European countries. Most countries restrict the use of biostabilised residual waste (BSRW) to landfill cover, whereas others have regulated it as marketable compost. Crucially, BSRW is set to lose its "recycled" status under the revised European Union waste framework, with probably tighter restrictions and increased costs imposed for the landfilling of organic waste. Our research aimed to investigate pyrolysis as an alternative technology to treat the 10–40 mm fraction of BSRW (representing 50% of BSRW generated). Pyrolysis at 700 °C was carried out and feedstock and pyrolysis products were characterized. Mass and energy balances showed that pyrolysis produced hot vapour/gas whose combustion may render the pyrolysis process energetically sustainable. Biochar comprises 30–50% of BRSW mass after removal of glass, metal and stones. Our results indicate that pyrolysis has the potential to create options for contributing to reduce the landfilling of BSRW; however, the presence of residual impurities may limit biochar applications. [ABSTRACT FROM AUTHOR]

When high-temperature steam is used as a medium to pyrolyze organic-rich shale, water steam not only acts as heat transfer but also participates in the chemical reaction of organic matter pyrolysis, thus affecting the generation law and release characteristics of gas products. In this study, based on a long-distance reaction system of organic-rich shale pyrolysis via steam injection, the effects of steam temperature and reaction distance on gas product composition are analyzed in depth and compared with other pyrolysis processes. The advantages of organic-rich shale pyrolysis via steam injection are then evaluated. The volume concentration of hydrogen in the gas product obtained via the steam injection pyrolysis of organic-rich shale is the highest, which is more than 60%. The hydrogen content increases as the reaction distance is extended; however, the rate of increase changes gradually. Increasing the reaction distance from 800 to 4000 mm increases the hydrogen content from 34.91% to 69.68% and from 63.13% to 78.61% when the steam temperature is 500 °C and 555 °C, respectively. However, the higher the heat injection temperature, the smaller the reaction distance required to form a high concentration hydrogen pyrolysis environment (hydrogen concentration > 60%). When the steam pyrolysis temperature is increased from 500 °C to 555 °C, the reaction distance required to form a high concentration of hydrogen is reduced from 3800 to 800 mm. Compared with the direct retorting process, the volume concentration of hydrogen obtained from high-temperature steam pyrolysis of organic-rich shale is 8.82 and 10.72 times that of the commonly used Fushun and Kivite furnaces, respectively. The pyrolysis of organic-rich shale via steam injection is a pyrolysis process in a hydrogen-rich environment. [ABSTRACT FROM AUTHOR]

The valorization of black liquor, a by-product produced in considerable quantities from the paper manufacturing processes, has demonstrated the effectiveness of thermal reconversion into pyrolysis gas, bio-oil, and bio-char, a sustainable approach placing the feedstock into a circular economy concept. The present study focused on developing disposal solutions through energy recovery via pyrolysis at 300 °C and 450 °C when lignite and nanomaterials (such as Cu-Zn-MCM-41, Ni-SBA-3, or Ni-SBA16) were used as catalysts. The results were compared to those of non-catalytic pyrolysis. The use of the Cu-Zn-MCM-41 catalyst proved to be efficient for pyrolysis gas production, reaching 55.22 vol% CH4. The increase in the calorific value of the pyrolysis gas was associated with the use of the Cu-Zn-MCM-41, showing a value of 42.23 MJ/m3 compared to that of the non-catalytic process, which yielded 39.56 MJ/m3. The bio-oil resulting from the pyrolysis with Cu-Zn-MCM-41 showed the highest energy value at 6457 kcal/kg compared to that obtained with the other two nanocatalysts, Ni-SBA-3 and Ni-SBA-16, as well as that of the raw material, which had a value of 3769 kcal/kg. The analysis of bio-char revealed no statistically significant differences when comparing the outcomes from using the various nanocatalysts, suggesting their minimal impact on the energy content. [ABSTRACT FROM AUTHOR]

The results of thermogravimetric and Fourier transform infrared (FTIR) analysis of polymer composite materials (PCMs) based on polyethylene (PE) and polycarbonate (PC) are presented and compared to PE and PC polymers. Empirical data are obtained for mathematical modeling, including the amount of solid residue upon pyrolysis, volatile yield, and ash content of the studied PCMs and polymers. The results of the mathematical modeling of the pyrolysis process at a temperature of 600°C are presented to quantitatively assess the composition of pyrolysis gas. [ABSTRACT FROM AUTHOR]

The ignition issue of the hypersonic aircraft remains a challenging task due to the extremely short residual time of milliseconds. To study the potential candidate of hydrogen peroxide for ignition enhancement, the ignition delay times of pyrolysis gas with the addition of 0–5000 ppm hydrogen peroxide were experimentally measured and quantitatively analyzed at temperatures of 833.8–962.1 K, equivalence ratios of 0.5–1.5, pressures of 31.9–48.8 bar, and the dilution of 45 vol% Ar. A novel injection system based on a Laval nozzle was designed to well atomize and evaporate the liquid hydrogen peroxide. The experimental results showed that the enhancing effect of hydrogen peroxide was proceeded by three stages, in which the decreasing efficiency gradually weakened with the increase of additive fraction. The ignition delay times of pyrolysis gas dramatically shortened by 66.1 % with 1000 ppm of hydrogen peroxide. Only a decrement of 19.1 % was obtained as the additive fraction increased from 1000 to 4000 ppm. The decline at 4000–5000 ppm even reduced to 2.0 %. It is suggested to add no more than 1000 ppm of hydrogen peroxide from the perspective of the highest acceleration efficiency on the ignition delay times of pyrolysis gas.

A comprehensive physical and mathematical model is proposed, as well as a method of analytical solution for the processes of heat and mass transfer in thermoprotective composite materials during phase transformations of composite material binders with the formation of pyrolysis gases and a porous coke residue, through which gases are filtered to the outer boundary and blown into the high-temperature boundary layer. Mathematical simulation is carried out on the basis of the identified law of decomposition of composite material binders without using models of the hard to formalize chemical kinetics and therefore suitable for most thermoprotective composite materials. The comprehensive physical and mathematical modeling includes the formation of a pyrolysis zone, the speeds of its motion inside the composite material, determining the density of composite material and pyrolysis gases in the pyrolysis zone, the density and stagnation pressure of gases in this zone, their nonisothermal filtration through the porous residue with injection into the boundary layer, as well as heat transfer in the presence of nonstationarily moving boundaries of phase transformations. Based on the relations of the proposed model, calculations were carried out, and their results were analyzed. [ABSTRACT FROM AUTHOR]

Copyright of Advances in New & Renewable Energy is the property of Editorial Office of Advances in New & Renewable Energy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Within the scope of this study, the effects of fast pyrolysis of sunflower oil cake on obtained product yields and product properties were investigated under non-catalytic condition and using clinoptilolite catalyst. The percentages of moisture, ash, volatile matter and fixed carbon content of sunflower oil cake used as raw material within the scope of the research were determined as 5.92%, 6.08%, 71.30% and 16.70%, respectively. According to the its elemental analysis results, the percentages of C, H, N and S were determined as 42.06%, 6.26%, 6.93%, 0.00%, respectively. The heating value was calculated as 17.13 MJ/kg. For this aim firstly, the effects of heating rate (100, 200, 300κ/min), pyrolysis temperature (400, 500, 600κ) and catalyst percentages (5%, 10%, 15%) on product yields (biochar, biooil and pyrolysis gas) were investigated. In the experiments conducted with the addition of clinoptilolite catalyst during fast pyrolysis of sunflower oil cake, it was determined that the catalyst did not change the solid product yield much, it considerably reduced the liquid product yield and increased the gas product yield. In the biochar samples, the highest heating value was obtained as 22.95 MJ/kg at 300°C/min heating rate and 500κ pyrolysis temperature conditions without catalyst. When the microscopic structure (SEM analysis) of the biochar samples was examined, it was understood that the porosity increased compared to the raw material. It was determined that the heating values of the pyrolysis gas samples obtained under the non catalyst-free condition were higher than those of the samples obtained under the non-catalytic condition. The highest lower heating value for obtained gas samples was obtained as 29.05 MJ/Nm2 at 400°C temperature and 100°C/min heating rate conditions Bio oil samples obtained by pyrolysis of sunflower oil cake at different temperatures and different heating rate with and without catalyst were examined by GC-MS method, and it was determined that especially phenol compounds (Phenol, Phenol, 2-methoxy-) were found in almost every sample. In addition, aromatic compounds such as Pyrazine-methyl, Pyrazine 2,6-dimethyl-(CAS) 2,6-Dimethylpyrazine have also been detected. [ABSTRACT FROM AUTHOR]

Microplastics, identified as an emerging environmental pollutant in marine ecosystems, necessitate immediate and comprehensive attention from organizations across various levels. The microsize of these plastic particles poses a significant threat to the environment as they effortlessly disperse throughout the biosphere via ocean waves. This study focuses on investigating the physicochemical properties of microplastic waste in a specific Southeast Asian regional area and evaluating its potential conversion into gaseous products through the pyrolysis process. Remarkably, the pyrolysis of microplastics resulted in an average syngas yield of 34.79%, demonstrating the viability of microplastic valorization. Furthermore, the pyro-solid-char produced exhibits a highly porous structure with minimal amounts of metal oxides, suggesting its potential utilization as fertilizer or catalyst. [ABSTRACT FROM AUTHOR]

An insightful understanding of the formation mechanism of process-inherent defects and deformation is increasingly important for the property evaluation and structural design of ceramic matrix composites (CMCs). For this purpose, a coupled thermal–diffusive–mechanical modeling approach was proposed by considering three important phenomena that occur during the pyrolysis process for manufacturing CMCs: variations of the physical and mechanical properties of the constituents, generation and diffusive of pyrolysis gas, and multiple thermal deformations. The synergistic effects of these three phenomena on the stress, damage development, microstructural morphology, and process deformation of SiC matrix composites were investigated using finite-element simulations. This new approach was validated by comparing the simulation and experimental results. Significant volume shrinkage of the matrix during the polymer-to-ceramic transformation resulted in large tensile stresses and subsequent highly fragmented microstructure in CMCs. The pyrolysis-gas-induced expansion on the matrix under a damage state may yield a positive process deformation of CMCs at the macroscale, overcoming the effects of the volume shrinkage of the bulk matrix at the microscale. The modeling approach is expected to guide high-quality manufacturing of CMCs and comprehensive studies of structure–processing–property relationships.

Carbon pyrolysis is one of the essential ways to improve carbon energy utilization and reduce environmental pollution. The main product of carbon pyrolysis process is tar, and improving tar yield can not only increase the resource utilization efficiency, but also reduce the pollution to the environment. Therefore, this paper investigates the application of Ni/MgO catalyst in the pyrolysis process of bituminous coal. The experimental results show that Ni/MgO catalyst can effectively activate small molecule radicals and make them combine with prominent molecule radicals stably to improve the tar yield. Meanwhile, when it is under the pyrolysis gas environment, pyrolysis temperature reaches 570 ℃, gas flow rate is 375 ml/min, and the catalyst is selected to be filled in the upper layer, the activation effect of Ni/MgO catalyst is more prominent, and it can significantly increase the tar yield and the proportion of light oil. Ni/MgO catalyst had the best effect in tar yield increase compared to other catalysts, but the performance was average in fair oil percentage increase. The catalyst could also reduce the number of aliphatics in the tar and increase the proportion of non-aliphatics, improving the tar quality.

An experimental study was made on burning velocity in powder-gas hybrid combustion in order to investigate the determination factor to alter the burning velocity caused by the addition of power in the premixed gas. A burner system was newly developed to visualize the dynamic flame behavior originally stabilized in a stagnation point flow field. Using the system, the instantaneous burning velocity and burning area by powder loading were obtained and analyzed. It was found that the burning velocity and burning area varied substantially in accordance with the powder loading amount. Data analyses exhibited that a positive correlation was found between them, suggesting that wrinkling shall be a major cause to alter the burning velocity. To understand the mechanism of wrinkle formation, the change of the flow field ahead of the flame with powder loading was measured. It is suggested that the wrinkles could be attributed to the pyrolysis gases evolved in the preheating zone, which could both increase the local burning velocity by increasing the local equivalence ratio and change the flow field due to the divergence flow generated by each powder. Further study would be needed to confirm the suggested mechanism.

The article is dedicated to describing the research of different ways, appliances and solutions for flammable gas supply, transportation and cooling, performed in terms of authors' PhD theses, related to pyrolysis gas production and application for electric power production. The main idea of this research is the investigation of opportunities of application of modern simple generally used technological solutions on pyrolysis gas power plants for the above mentioned units design. The research is related to different ways of pyrolysis gas cooling and also to the ways of the gas supply from gas generator to the consumer. Another goal is to create a systematic approach to the automation of pyrolysis gas production and transportation onto future pyrolysis gas powered electric power plants. [ABSTRACT FROM AUTHOR]

Biomass is a promising resource for the production of renewable energy, liquid fuels, and chemicals. Microwave pyrolysis is one of the directions of multifunctional conversion of raw materials. In the present work, the effect of microwave power on the characteristics of sawdust pyrolysis is studied. With an increase in power, the maximum yield of combustible gases increased, and a large proportion of the total pyrolysis time included the useful time for the release of gases. An increase in power affected the yield of individual gases non-linearly and on a different scale. The average yield of CO and CO2 remained practically unchanged when the microwave power was increased from 840 to 1760 W. However, with a further increase in power to 2200 W, there was a significant increase in the average yield of CO and CO2 (2.5 and 1.4 times, respectively). An increase in power by 2.6 times contributed to an increase in the average yield of CH4 by 5 times and H2 by 3.8 times. The increased power of microwaves contributed to the degassing of wood and intensification of secondary pyrolysis reactions, which resulted in a decrease in the mass of the solid residue by 5.3 times and a decrease in the liquid product yield by 2.7 times. A comprehensive analysis using MCDA showed that an increase in energy costs with an increase in microwave power is integrally compensated by an improvement in pyrolysis performance. So, when the power was varied from 840 W to 2200 W, the pyrolysis efficiency indicator increased by 1.3–2.2 times, considering the growth in energy consumption. [ABSTRACT FROM AUTHOR]

To study the gas product yield characteristics during in-situ pyrolysis of deep buried anthracite for gas extraction, high-temperature and high-pressure triaxial tester and gas chromatography were used to obtain the pyrolysis gas yield and products of anthracite in the range of 100-600 ℃. The relationship between product and permeability was analyzed. The study showed that the variation of pyrolysis gas yield with temperature can be divided into four stages: the first stage(degassing stage) from 100 ℃ to 200 °C, where the anthracite produces small amounts of gas and the precipitated gas is mainly N2 and O2. The second stage ayayrolysis initiation stage) from 300 ℃ to 400 ℃, where the anthracite coal is further pyrolyzed and the gas yield further increases, and the gas is mainly composed of CH4, CO2, H2 and C2H6 produced by coal pyrolysis. 400 ℃ is the first peak of pyrolysis gas production. The range of 400-500 ℃ is the third stage(pyrolysis stage), due to the thermal stability of organic substances in anthracite, resulting in lower gas production. The range of 500-600 ℃ is the fourth stage(cracking stage), and pyrolysis gas production once again continues to increase. The permeability is influenced by the gas yield and gas production during pyrolysis.

The relevance of the research is caused by the need to conduct numerical studies of combustion in existing internal combustion engines with various injection designs and ignition systems for the fuel-air mixture of steam-gas pyrolysis products to generate mechanical energy on the crankshaft shaft. These directions will expand the role of pyrolysis of biomass, secondary products of wood processing enterprises and municipal solid waste in the field of heat and power complex. The main aim of this study is to evaluate the efficiency of combustion of gas-steam products of pyrolysis of wood waste in an internal combustion engine designed to use diesel fuel in order to be able to test this system. Objects: four-stroke diesel internal combustion engines of a V-shaped cylinder arrangement with and without a turbocharger, powered by the combustion of combined-cycle products of pyrolysis of wood waste. Methods: numerical studies based on mathematical algorithms of systems, cycles and main parts of naturally aspirated and turbocharged diesel internal combustion engines based on thermal calculations and thermal balance. Results. The authors have developed the mathematical model and a simulation program for thermal calculation of a four-stroke internal combustion engine with a V-shaped arrangement of cylinders with direct injection of combined-cycle products of wood pyrolysis into the combustion chamber with and without a turbocharging system. The analysis of the influence of the crankshaft speed, the number of cylinders on power, torque, and specific fuel consumption was carried out. It is shown that an increase in the number of cylinders with the same working volume of an internal combustion engine leads to growth in power and torque, while the specific consumption of steam-gas pyrolysis products decreases. It is noted that the combustion of steam-gas products of pyrolysis in an internal combustion engine leads to an increase in the temperature of the exhaust gases relative to diesel fuel combustion. For turbocharged internal combustion engines, the increase in exhaust gas temperature is about 50 °C, without turbocharging – about 100 °C. It was established that in the four-stroke diesel engine of internal combustion when burning pyrolysis gas obtained from wood waste, mass consumption is 7,5÷8,6 times more than diesel fuel is required to produce the same amount of electric energy. It was revealed that a diesel engine with a turbocharger is more economical and effective than a power unit without a supercharger. At a speed of 3000 min–1 of a 12 cylinder engine with a turbocharger, pyrolysis gas consumption saving is 11,9 %, effective capacity and torque are 10,0 % higher than that of an internal combustion engine without a supercharger. One of the most available at the moment for burning pyrolysis gas is a four-stroke V12 diesel engine with a turbocharged YAMZ 845.10 with a working volume of 25,86 liters, maximum capacity of 537 kW (730 hp), maximum torque of 2788 N⸱m at rotation frequency 1500÷3000 rpm.

The relevance of the study is caused by the need to find technologies that can improve the environmental friendliness of the use of organic fuels in the process of energy supply. The main aim is research of microwave pyrolysis of solid organic fuels with different degrees of metamorphic transformation. Objects: solid organic fuels with varying degrees of metamorphic transformation, namely, wood waste (pine sawdust), lowland peat (Sukhovskoe deposit, Tomsk region), brown coal (Talovskoe deposit, Tomsk region), hard coal (grade D, Kuznetsk basin, Kuzbass). Methods. The characteristics of the initial fuel were determined according to generally accepted methods: humidity – SS R 52917-2008, volatile matter yield – according to SS R 55660-2013. The ash content of sawdust was determined according to SS R 56881-2016, peat – SS 11306-2013, coal – SS R 55661-2013. The fundamental difference between the standards used in terms of determining the ash content lies in the prescribed parameters of the analysis procedure (temperature, speed, time). The heat of combustion was determined using an ABK-1V calorimeter (RET, Russia) in accordance with SS 147-2013. The elemental composition of the feedstock and the solid carbon residue after its processing (C, H, N, S) was determined using a Vario Micro Cube analyzer (Elementar, Germany), using a standard sample (Sulfanilamide) as a verification. Research of the processing of the concerned fuels by the method of traditional slow-bed pyrolysis was carried out by the method of synchronous thermogravimetric analysis and differential scanning calorimetry using an STA 449 F3 Jupiter instrument (Netzsch, Germany). Microwave pyrolysis was implemented on a specially designed experimental stand (magnetron power 750 W, carrier frequency 2,45 GHz). The pyrolysis gas composition (the content of components such as H2, CH4, CO, СО2) was recorded in real time using a Test-1 gas analyzer (Boner, Russia). Results. By the method of differential thermal analysis, it was established that the temperature of the end of thermal transformation for biomass (sawdust and peat) is 600–650 °C, for brown coal – 850 °C, for hard coal – 900 °C. Comparing the results of slow-bed and microwave pyrolysis, it was noted that during microwave pyrolysis of fuel, 9,5–11,7 % less solid carbon residue is formed, and the yield of volatile (liquid and gaseous products) increases. At the same time, the pyrolysis gas generated in the process of microwave pyrolysis almost does not contain ballast CO2 in its composition, which, together with the low yield of carbonaceous residue, indicates a higher efficiency of thermal fuel processing compared to slow-bed pyrolysis. It is noted that with an increase in the degree of fuel metamorphism in the process of microwave pyrolysis, the share of generated synthesis gas (Н2+СО) in relation to the amount of methane obtained decreases, which is associated with the composition of the initial processed raw material: change of (СО+Н2)/СН4 in the pyrolysis gas correlates with the change of (Н+О)/С in initial fuels.

In the face of threats related to energy supply and climate change, the use of biomass is gaining importance, particularly in distributed energy systems. Combustion of biomass, including residue biomass, is considered one of the routes to increase the share of renewables in energy generation. The modeling of gaseous phase reactions remains crucial in predicting the combustion behavior of biomass and pollutant emissions. However, their simulation becomes a challenging task due to the computational cost. This paper presents a numerical analysis of the combustion process of a gas mixture released during biomass decomposition in a domestic 25 kW coil-type boiler. Three types of biogenic fuels were taken into consideration. The work aimed at examining the available tools for modeling gas burning, thus the geometry of the system was limited only to the 2D case. The thermodynamic equilibrium composition of pyrolysis gas was determined and implemented in Ansys to simulate the process. The computational results showed the potential of detailed, but reduced, combustion mechanisms of CH 4 / CO / H 2 mixtures in predicting the main process features. The mechanism involving 85 reactions appeared to be more reliable compared to that comprising 77 reactions, particularly for volatiles with higher H 2 content, whilst offering an acceptable calculation time. The burning characteristics obtained for volatiles with less CH 4 and more H 2 are in good agreement with the real operation conditions reported for the boiler. [ABSTRACT FROM AUTHOR]

Copyright of Advances in New & Renewable Energy is the property of Editorial Office of Advances in New & Renewable Energy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Conventional methods used to determine pyrolysis gas composition are based on chemical kinetics. The mechanism of those reactions is often unknown, which makes the calculations more difficult. Solving complex chemical reactions' kinetics involving a nonlinear set of equations is CPU time demanding. An alternative approach is based on the Gibbs free energy minimization method. It requires only the initial composition and operation parameters as the input data, for example, temperature and pressure. In this paper, the method for calculating the pyrolytic gas composition from biogenic fuels has been presented, and the thermogravimetric experimental results have been adopted to determine the total gas yield. The studied problem has been reduced to the optimization method with the use of the Lagrange multipliers. This solution procedure is advantageous since it does not require knowledge of the reaction mechanism. The obtained results are in good agreement with experimental data, demonstrating the usefulness of the proposed method. [ABSTRACT FROM AUTHOR]

The article describes the real existing project of the furnace performed on the facilities of the Secret-Service metal works company located in the Kyiv Region. It was ordered by a local waste disposal company that imports RDF and accepts garbage from the vicinity and produces RDF by itself as well. The purpose of this article is to show the opportunities of application of the quite simply designed furnace for the purposes of wastes disposal either on enterprises or within a range of an average town. The current project was implemented in reality, allowing getting rid of industrial and household garbage within the ecologic laws of the Ukraine, including the disposal of plastics, rubber, packages, etc. The proposed example of successful pyrolysis technology application in the furnace can be a good basis for further research dedicated to the creation of more advanced furnaces' types and also to the creation of the additional afterburner furnace. [ABSTRACT FROM AUTHOR]

Pyrolysis process is an important process used in the disposal of waste in recent years. The pyrolysis products can be recovered and used in different areas. In addition, the purification of gaseous products is important from an environmental point of view. Within the scope of this study, pyrolysis of HDPE and LDPE-type plastic wastes was carried out. Solid product (char), which has a developed surface structure, was used in the purification of the gas product formed from the same pyrolysis process by adsorption. The pyrolysis chars obtained at 500 °C, 600 °C, and 700 °C temperatures were used as adsorbent with and without chemical activation. According to the results of the BET analysis, the surface area of the cokes with the activation method increased 18 times in HDPE and 70 times in LDPE compared to their non-activated state. Adsorption efficiencies of 60–80% and 40–90% were obtained with HDPE and LDPE cokes. In the adsorption columns formed from pyrolysis chars, the components that HDPE-type activated chars adsorbed with the highest efficiency in the adsorption of pyrolysis gases were toluene, styrene, and ethylbenzene, respectively, at 500 °C, 600 °C, and 700 °C. In LDPE, these components were pentane, octane, and benzene, respectively. With this study, an alternative way to the use of char, which is one of the by-products after the disposal of plastic wastes by the pyrolysis method, was presented, and the purification of pyrolytic gas, another pyrolysis product with known toxic properties, was provided by adsorption method. It is also important to recover the adsorbents (waste adsorbents) used in the adsorption process in accordance with the zero waste approach. The calorific values of these waste adsorbents were investigated and their usability as an alternative fuel to coal was investigated. [ABSTRACT FROM AUTHOR]

With the urbanization and population growth, the disposal of plastic waste has become a significant challenge, as the traditional methods often result in pollution and resource wastage. Pyrolysis technology offers a sustainable solution by converting the waste plastics into valuable gas or liquid fuels. The co-pyrolysis of plastics and biomass is an effective approach for synergistically managing these two types of solid waste. The polyethylene (PE) and salix psammophila (SP) was used to investigate the gas production characteristics and polycyclic aromatic hydrocarbons (PAHs) formation during the co-pyrolysis. Additionally, Cu/ZSM-5, Co/ZSM-5, and Ni/ZSM-5 catalysts were employed to investigate the effects of different metal-loaded catalysts on the co-pyrolysis process. The results indicate that, with the increase of the pyrolysis temperature, the yield of gas-phase products gradually increases, solid residue decreases, and liquid-phase products initially increase before declining, reaching their maximum at 500 °C. The synergistic effect promotes the formation of C 2 H m (C 2 H 2 , C 2 H 4 , C 2 H 6) and CH 4 , leading to the increase of the gas-phase product yields compared to the individual pyrolysis. The addition of catalysts further enhances the gas production: Cu/ZSM-5 boosts H 2 yield, Co/ZSM-5 shows selectivity for CH 4 and C 2 H m , and Ni/ZSM-5 exhibits better selectivity for CO and H 2. Under the various pyrolysis conditions, aromatic compounds and aliphatic hydrocarbons consistently dominate the liquid-phase products. With the increase of the pyrolysis temperature, the proportion of aliphatic hydrocarbons decreases, while the proportion of aromatic compounds increases. The addition of catalysts reduces the proportions of both aliphatic and aromatic compounds. PAHs generation is temperature-dependent, significantly increasing at 700 °C. At the low pyrolysis temperatures, the co-pyrolysis reduces PAHs yield, but at high temperatures, PAHs formation increases. The addition of catalysts decreases PAHs yield and toxicity equivalency. Cu/ZSM-5 promotes the cracking of two-ring PAHs, reducing two-ring PAHs yield. Co and Ni catalysts enhance the selective aromatization of small hydrocarbon molecules, forming low-ring PAHs and limiting PAHs aggregation. Overall, Ni/ZSM-5 demonstrates the best performance in enhancing gas production and reducing PAHs emissions, followed by Co/ZSM-5 and Cu/ZSM-5. • The co-pyrolysis behavior of polyethylene and salix psammophila were investigated. • The synergistic effect of PE and SP promotes the formation of C n H m and CH 4. • Metal-loaded catalysts increase the yield of pyrolysis gas. • The addition of catalysts reduces the generation of PAHs and toxic equivalents. • For increasing product gas and reducing PAHs, Ni/ZSM-5 > Co/ZSM-5 > Cu/ZSM-5. [ABSTRACT FROM AUTHOR]

Due to the high molecular weight, high viscosity and strong instability of heavy bio-oil from rape straw, it is necessary to explore new high-value utilization methods. Heavy bio-oil based carbon material (HBC) was prepared via carbonization and activation assisted by pyrolysis gas, and the basic Mg-Zr-O catalysts using HBC as the carrier (Mg-Zr-O/HBC) was synthesized for the aldol condensation of cyclopentanone to produce aviation fuel precursor. The effect of activation condition on the physicochemical properties of HBC and Mg-Zr-O/HBC were evaluated, the evolution of gas component before and after activation was explored, and the catalytic performance of Mg-Zr-O/HBC in the aldol condensation of cyclopentanone for the synthesis of aviation fuel was tested. Instead of traditional KOH activation, pyrolysis gas activation was beneficial for the reduced pollution and increased calorific value of the gas, making it an environmentally friendly method. The results showed that the activation of biochar (BOC) was improved with lower pyrolysis gas flow, higher activation temperature and longer activation time. The pore structure of carbon material was significantly improved, and the specific surface area was boosted from 15.25 m2/g3 to 627.61 m2/g3. Mg-Zr-O was evenly distributed on HBC, and a large number of weak and medium basic sites were found in Mg-Zr-O/HBC, which was quite favorable for the aldol condensation. In the aldol condensation of cyclopentanone, Mg-Zr-O/HBC presented the excellent production of the targeted C10+C15 condensates of 84.95 %, which was comparable to that prepared with KOH as activator. After 8 repeated runs, the yield of the targeted condensates remained at 73.33 %. In general, it provided an environmentally friendly strategy for the preparation of HBC and the high-value utilization of pyrolysis gas assisted by pyrolysis gas for the activation of BOC. [Display omitted] • The activation with pyrolysis gas for the preparation of porous carbon was tried. • High value utilization of pyrolysis gas has been achieved. • A large number of weak and medium basic sites were found in Mg-Zr-O/HBC. • The aldol condensation catalyst held the favorable basic sites. • The requirements of circular economy development have been satisfied. [ABSTRACT FROM AUTHOR]

Biomass carbon materials have attracted attention in various fields due to their excellent properties. In this study, CH 4 derived from biomass pyrolysis was utilized as a carbon source gas to synthesize carbon materials by chemical vapor deposition (CVD) in a two-stage reactor with purification system, with Fe3+-loaded nickel foam as the substrate under an argon atmosphere, using a self-designed experimental platform. The reaction process was optimized by examining the effects of the catalyst type, reaction temperature, reaction time, and gas flow rate on the structure and morphology of the carbon materials. The optimal preparation condition was to use FeCl 3 ethanol solution as catalyst, with CH 4 flow rate of 50 ml/min at 1000 °C for 25 min. The high quality carbon materials with uniform diameters (250–500 nm) were obtained on nickel foam substrate. The carbon materials obtained under optimal conditions were characterized and analyzed to investigate their excellent properties. Surface morphology and structure of as-formed carbon materials were characterized by SEM. The analysis of the XRD spectra and the Raman spectroscopy showed that the graphite diffraction peak (002) at 26.6°, the calculated intensity ratios for I D / I G and I 2D / I G were 0.257 and 0.545, respectively, indicated high degree of graphitization and purity of the carbon materials. Furthermore, the growth mechanism of carbon materials on the nickel foam substrate was discussed. • The preparation of carbon materials by vapor deposition with Fe3+-modified nickel foam from biomass pyrolysis gas was studied. • The effects of catalyst types, reaction temperature, reaction time and gas flow rate on the morphology of carbon materials were discussed. • The results showed that the optimal preparation conditions of carbon materials can be obtained using FeCl 3 ethanol solution as catalyst, the CH 4 flow rate of 50 sccm at 1000 °C for 25 min. • The analysis of the XRD spectra and the Raman spectroscopy showed that the graphite crystal structure of carbon materials generated under the optimal preparation conditions was good. [ABSTRACT FROM AUTHOR]

Suppression of forest fires has been one of the important research directions in the field of fire safety, ammonium phosphate and its mixture of inhibitors commonly used in solid combustible fires, for forest fire scenarios, also has a good fire suppression effectiveness, inexpensive and easy to store, but also the current suppression of forest fires is one of the main inhibitors. However, there are few studies on the interaction between ammonium phosphate and forest fires. In this paper, to facilitate the study, we enter the previous research ideas for gas fires, reduce the scale of the research object, establish a small-sized simplified flame model for suppressing wood fires, take red pine wood as the research object, analyze the pyrolysis gas components after high-temperature pyrolysis, and construct the Cup-burner experimental system, together with an improved powder delivery control system, so that the process of NH4H2PO4 powder quenching fuel flames such as red pine pyrolysis gas at 350 °C, 450 °C and 550 °C was well presented on this device. It was found that the flame morphology was not only related to the gas composition but also the amount of NH4H2PO4 powder added and the particle size; the Minimum fire extinguishing concentration(MEC) value was not only related to the gas composition but also the particle size of NH4H2PO4 powder. This is because the CO2 content decreases and the H2 and CH4 content increase significantly in the gas composition at 550 °C compared to the 450 °C gas composition. Among the same pyrolysis gas components, the MEC value gradually increased as the particle size of NH4H2PO4 powder decreased, and the MEC value of 30 μm–40μm particle size powder was the lowest, and the difference between the particle size MEC value and the other two particle sizes was large, while the difference between the MEC values of 20 μm–30μm particle size powder and 10 μm–20μm particle size powder was small; according to the Cup-burner test The chemical thermodynamic analysis was carried out according to the results of the Cup-burner test to obtain the proportion of NH4H2PO4 powders playing a physical role in fire extinguishing. When NH4H2PO4 powder is involved in syngas/air combustion, the end product is P2O5 and xsp = 2.35%. When the end product is HPO3, xsp = 7.29%. The products were collected after the interaction of NH4H2PO4 powder with the synthesis gas flame, and the analysis of the products revealed that the products were sticky and not dry solids, and the material analysis of them revealed that they contained more HPO3 and its mixture, which shows that the physical heat absorption played a greater role when NH4H2PO4 powder interacted with the synthesis gas flame.

The paper presents the results of experimental research into lab-scale microwave pyrolysis of wood biomass. The influence of the surface area and the structure of the biomass layer on the characteristics of pyrolysis during microwave heating are discussed. We have established that the biomass layer structure and surface area have a significant effect on the yield of pyrolysis gas. The approach of creating artificial deformation of the biomass layer was tested. The elements of artificial porosity made it possible to increase the CO yield by 18% and 32% compared to the pyrolysis of a biomass layer with artificial channels and a uniform layer, respectively. The concentration of H2 was 33% higher compared to the layer without artificial pores and 3% lower compared to artificial channels. The yield of CO2 increased by 25%, and the yield of CH4 doubled. The experiments showed that the distribution of biomass on a half of the bottom of the crucible and the additional porosity of the biomass layer surface effectively increase the yield of the pyrolysis gas components. Recommendations for increasing the efficiency of microwave pyrolysis of biomass were formulated. [ABSTRACT FROM AUTHOR]

The global energy industry works towards an increased use of carbon-neutral biomass. Nutshell represents a regional bio-waste, i.e., a bio-energy resource. Pyrolysis is a common method for processing biomass into valuable energy products. The heat demand, however, limits pyrolysis applications. Yet, such demand may be addressed via exothermic pyrolysis reactions under selected operation conditions. Making the pyrolysis of Siberian pine nutshell autothermic comprised the objective of the study. The study involved analytical methods together with a pyrolysis experiment. The analytical methods included a thermogravimetric analysis combined with differential scanning calorimetry and an integrated gas analyzer. Thermophysical characterization was executed using a thermal diffusivity analyzer with the laser flash method. At 650 °C, pyrolytic heat was released in the amount of 1224.6 kJ/kg, exceeding the heat demand of 1179.5 kJ/kg. Pyrolysis at a lower temperature of 550 °C remained endothermic, although the combusted gas product provided 847.7 kJ/kg of heat, which, together with exothermic release, covered the required heat demand for the pyrolysis process. [ABSTRACT FROM AUTHOR]

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Biomass is a promising resource for the production of renewable energy, liquid fuels, and chemicals. Microwave pyrolysis is one of the directions of multifunctional conversion of raw materials. In the present work, the effect of microwave power on the characteristics of sawdust pyrolysis is studied. With an increase in power, the maximum yield of combustible gases increased, and a large proportion of the total pyrolysis time included the useful time for the release of gases. An increase in power affected the yield of individual gases non-linearly and on a different scale. The average yield of CO and CO2 remained practically unchanged when the microwave power was increased from 840 to 1760 W. However, with a further increase in power to 2200 W, there was a significant increase in the average yield of CO and CO2 (2.5 and 1.4 times, respectively). An increase in power by 2.6 times contributed to an increase in the average yield of CH4 by 5 times and H2 by 3.8 times. The increased power of microwaves contributed to the degassing of wood and intensification of secondary pyrolysis reactions, which resulted in a decrease in the mass of the solid residue by 5.3 times and a decrease in the liquid product yield by 2.7 times. A comprehensive analysis using MCDA showed that an increase in energy costs with an increase in microwave power is integrally compensated by an improvement in pyrolysis performance. So, when the power was varied from 840 W to 2200 W, the pyrolysis efficiency indicator increased by 1.3–2.2 times, considering the growth in energy consumption.

The phenomenon that laboratory pyrolysis experiments produce much wetter gases than those in natural reservoirs is a long-recognized and debated problem in the investigation of natural gases in sedimentary basins. In this study, we explore the discrepancy by pyrolyzing a type II kerogen from the Woodford Shale in Oklahoma, compared with the previous results on the produced natural gases from the Arkoma Basin generated from the same source rock (Liu et al., 2019) with the discussion of gas and isotopic compositions at bulk and position-specific (PS) levels. An improved GC-pyrolysis-GC IRMS method is applied for the determination of PS δ13C of propane produced in the pyrolysis of the Woodford Shale at Easy %R o from 0.76 to 3.27. Kinetic and thermodynamic considerations of the chemical and isotopic compositions of the natural and laboratory pyrolysis gases suggest that the generation of light hydrocarbons involves uni-directional cracking reactions, exchange reactions with water, and likely reversible reactions among light hydrocarbons and other H-containing volatiles. After the gas generation in the unconventional Woodford Shale reservoirs, the C 1 -C 4 gases might have approached close to chemical equilibrium of C 1 -C 3 and isotope equilibrium of C 2 -C 1 and C 3 -C 1 pairs at their peak temperatures. The capping H for the generation of C 1 -C 4 in the Woodford Shale gases appears to have experienced at least partial exchange with the water, while that in the pyrolysis gases is only originated from organic-bound compounds with large kinetic isotope effects (KIE). Our findings indicate that elevated compound-specific and PS δ13C values of propane in the wet-gas cracking stage are significantly influenced by the breakdown of the thermally stable compounds (e.g., remaining kerogen, residues). A first synthesis of PS δ13C and δ2H isotopic compositions of propane from this study and the literature data suggests relatively similar isotopic structures of propane precursors in kerogens. This study demonstrates that PS isotope analysis of propane can contribute to identifying various geological (e.g., maturation, wet-gas cracking, H exchange, diffusion) and biodegradation processes. [ABSTRACT FROM AUTHOR]

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Eucalyptus is one of the world's most important industrial raw material forest species, with wide planting and a fast-growing rate. At the same time, eucalyptus has demonstrated high photosynthetic efficiency and strong carbon sequestration ability, which has great potential as biomass energy. Solid oxide fuel cells (SOFCs) can directly convert the chemical energy in fuel into electricity with high conversion efficiency, as well as having a wide fuel source and pollution-free product. Here, we present the great potential of coupling eucalyptus derivatives (eucalyptus char and pyrolysis gas produced in situ from eucalyptus branch powder) with SOFCs for power generation. It is shown that the pyrolysis gas of the eucalyptus branch contains a variety of fuel gases, such as CO, H 2 , and CH 4. Besides, the eucalyptus chars contain a slight amount of Ca, K, and other elements, which are beneficial for the Boudouard reaction. At 850 °C, a typical maximum power density of 497 and 826 mW cm−2 can be achieved from electrolyte-supported and anode-supported SOFCs, respectively, using eucalyptus-derived biomass as fuel. • Eucalyptus derivatives are coupled with SOFCs for power generation. • At 850 °C, peak power densities of 497 and 826 mW cm−2 are achieved. • Combining pyrolysis gas with SOFC using a solid-state device is feasible. [ABSTRACT FROM AUTHOR]

This work offers a comprehensive investigation of the pyrolysis products—liquid, gas, and solid derived from cooked food waste (CFW) at different heating rates (15–100 °C/min). The heating rate significantly influenced the yield of pyrolysis products. The maximum yield of bio-oil (oil + aqueous) was achieved at a heating rate of 50 °C/min, py-gas at 100 °C/min, and biochar at 15 °C/min. The yields were 34 wt% for bio-oil, 30 wt% for py-gas, and 32 wt% for biochar. Analysis of the bio-oil revealed significant proportions of fatty acids (Methyl-methyltetradecanoate) and esters (Oleic acid ethyl ester), constituting 25 %, and 26 % at 15 °C/min but declining with increasing heating rates. Another ester (9-Octadecenoic acid methyl ester) was found across all heating rate with highest concentration of 33 % at 100 °C/min. Aliphatic hydrocarbons (Octane, Dodecene, Heptadecane, Tetradecyne, Undecane, Dimethylhepta-1,3-triene, Tetradecane, Nonadecane), constituted highest concentration of 12 % at 25 °C/min and aromatic hydrocarbons (Toluene) showed maximum presence of 4 % at 50 °C/min. The aqueous phase showcased cyclic nitrogenated compounds (Piperidine), anhydrosugars (DGP), and furanics (Furanmethanol), with the highest concentrations of 46 %, 12 %, and 38 %, respectively observed at 100 °C/min. Instantaneous py-gas analysis indicated an elevated presence of CO 2 and CO in the initial pyrolysis stages (up to 70 min) followed by higher H 2 in the latter stages (>70 min). While increasing heating rates (15–100 °C/min) boosted cumulative fractions of CO 2 and CO, the highest H 2 fraction was observed at 50 °C/min. The proximate and ultimate analysis of biochars indicated increased ash, fixed carbon, HHV and H/C compared to raw CFW. The surface area and morphology were positively influenced by an increase in heating rate, resulting in a microporous biochar having maximum surface area of 340.6 m2/g at 50 °C/min. [Display omitted] • Pyrolysis of cooked food waste (CFW) was performed at varying heating rates. • The oil phase of bio-oil contained an abundance of esters and fatty acids. • High concentration of Piperidine and Furanmethanol found in aqueous phase. • Py-gas yield was highest at 100 °C/min while maximum H 2 was produced at 50 °C/min. • CFW-biochars showed highly porous structure with maximum surface area of 340 m2/g. [ABSTRACT FROM AUTHOR]

Ketonization of bagasse pyrolysis gas was performed over red mud-based oxides. The maximum yield of ketones in the catalytic conversion of bagasse pyrolysis gas over original red mud was 18.66% at 420 °C. To promote the oxidability of red mud and obtain a higher yield of ketones, the effect of metal oxides (CeO 2 , MnO 2 , TiO 2 , CaO, ZrO 2) loading and loading amount of CeO 2 on red mud on ketonization of bagasse pyrolysis gas were studied. The highest yield of ketones of 27.86% was obtained over red mud-based oxides with 40 wt% CeO 2 loading. The oxidability of the catalyst was enhanced greatly by the high loading of CeO 2 , leading to the peroxidation of acetone as the side reaction. To control the oxidability and cut costs, bimetallic oxides were loaded on red mud. The yield of ketones reached 30.12% over the composite red mud catalyst with the loading of 20 wt% CeO 2 and 20 wt% MnO 2. The rough coating of MnO 2 on the surface of red mud was beneficial to the loading of CeO 2 , resulting in smaller and more uniform grains. This study provides the efficient utilization of red mud and biomass as solid wastes for high-valued chemicals and fuels. [ABSTRACT FROM AUTHOR]

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°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. [ABSTRACT FROM AUTHOR]

THE PURPOSE. Consider a renewable energy source. Compare the proposed design with other pyrolysis technologies and make sure that the proposed design will reduce fuel consumption. METHODS. This article proposes the design and technological principle of the process of pyrogenetic wood processing with the production of various compositions of pyrolysis gas and charcoal. RESULTS. The article describes the proposed design, calculates the heat balance for it, and determines the operational parameters of the technological process. CONCLUSION. The main positive difference between the proposed plant design and technology from other pyrolysis technologies is a high level of fuel economy due to heat utilization at intermediate stages of the process. The heat of the cooled charcoa l and the waste products of complete fuel combustion are utilized. The developed design allows reducing fuel consumption, as well as the range of gaseous components obtained as a result of pyrogenetic decomposition of raw wood in a direct -flow pyrolysis plant can be increased.

This study investigates the behaviour of pyrolysis gas, generated by the thermal decomposing of biomass, in a pilot size reactor. The discreet mathematical model, Lattice Boltzmann, has adopted for mathematical simulation of flow of pyrolysis gas across a porous bed of biomass. The effect of permeability, pressure gradient, voidage of bed, density, temperature, and the dynamic viscosity on the mass flow rate of gas is examined by simulating the gas flow across the fixed bed of hardwood. The Darcy equation is used to estimate the flow rate of gas across the fixed bed of hardwood chips. The temperature in the reactor varies from 32 °C to 600 °C. The reactor has an external diameter of 220 mm and the vertical height of 320 mm. Rockwool insulation is used to prevent heat loss across the reactor. The external heating element of 2 kWe was provided to trigger the pyrolysis reaction. The properties of the system have been recorded by the pressure and temperature sensors, which are retrofitted along the periphery of the reactor. The temperature sensors are located at 80 mm apart from each other; whereas the pressure sensor, placed at the bottom circumference of the reactor. The effect of input parameters on the flow properties of gas is also examined to add up the qualitative assessment of the system to biomass pyrolysis. The polytropic equation of gas is found to be PV2.051 = C, whereas the compressibility of gas varies from 0.0025–0.042 m2·N–1.

Conventional methods used to determine pyrolysis gas composition are based on chemical kinetics. The mechanism of those reactions is often unknown, which makes the calculations more difficult. Solving complex chemical reactions’ kinetics involving a nonlinear set of equations is CPU time demanding. An alternative approach is based on the Gibbs free energy minimization method. It requires only the initial composition and operation parameters as the input data, for example, temperature and pressure. In this paper, the method for calculating the pyrolytic gas composition from biogenic fuels has been presented, and the thermogravimetric experimental results have been adopted to determine the total gas yield. The studied problem has been reduced to the optimization method with the use of the Lagrange multipliers. This solution procedure is advantageous since it does not require knowledge of the reaction mechanism. The obtained results are in good agreement with experimental data, demonstrating the usefulness of the proposed method.

Copyright of Journal of Engineering for Thermal Energy & Power / Reneng Dongli Gongcheng is the property of Journal of Engineering for Thermal Energy & Power and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The paper presents the results of experimental research into lab-scale microwave pyrolysis of wood biomass. The influence of the surface area and the structure of the biomass layer on the characteristics of pyrolysis during microwave heating are discussed. We have established that the biomass layer structure and surface area have a significant effect on the yield of pyrolysis gas. The approach of creating artificial deformation of the biomass layer was tested. The elements of artificial porosity made it possible to increase the CO yield by 18% and 32% compared to the pyrolysis of a biomass layer with artificial channels and a uniform layer, respectively. The concentration of H2 was 33% higher compared to the layer without artificial pores and 3% lower compared to artificial channels. The yield of CO2 increased by 25%, and the yield of CH4 doubled. The experiments showed that the distribution of biomass on a half of the bottom of the crucible and the additional porosity of the biomass layer surface effectively increase the yield of the pyrolysis gas components. Recommendations for increasing the efficiency of microwave pyrolysis of biomass were formulated.

Summary: The pyrolysis gas consisting of 29.4% CH4, 21.3% C2H4, 30.8% C2H6, and 18.5% C3H6 in mole fraction is presented, as the surrogate of the actual gaseous pyrolysis products. At the conditions of TC = 877.7‐963 K, PC = 3.22‐4.37 MPa, φ = 0.5 and 1.0, the ignition delays of pyrolysis gas/air (diluted with 52% Ar) have been measured. With TC or PC increasing, the ignition delay time decreases. The auto‐ignition of φ = 1.0 is faster than that of φ = 0.5. Furthermore, two widely used small hydrocarbons chemical mechanisms are validated with the measured results. The USC‐II mechanism can well predict experimental results at high‐T regimes, but fails at low‐T regimes. By sensitivity analysis of temperature, the two elementary reactions C2H6 + OH = C2H5 + H2O (negative sensitivity coefficient) and C3H6 + OH = aC3H5 + H2O (positive sensitivity coefficient) have been identified, which have higher reactivity at low‐T and lower reactivity at high‐T. Considering the extreme uncertainty of rate constants of C3H6 + OH = aC3H5 + H2O, the kinetic parameters have been modified for improving the predictions. The validated results indicate that the optimized mechanism improves predictions of the auto‐ignition behavior at low temperature regimes. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: The purpose of this article is to show the opportunities of application of the pyrolysis gas as a fuel for gas turbine power plants based on decommissioned gas turbine engines, including those from aircraft -- either turboprop or turboshaft, or both, and also those used on ground vehicles such as tanks and marine engines as well. Methods: The article describes the technology of pyrolysis of different materials for obtaining pyrolysis gas and its further application as a fuel for internal combustion engines was developed in the end of XIX century and was successfully applied for automobile, marine and railway locomotive piston engines till the mid XX century when large oil reservoirs were discovered all around the World. Results: the current research not only proves that there exists an economic benefit of application of pyrolysis technology even at nowadays, but also an ecological one, allowing getting rid of garbage Discussion: The proposed examples of successful pyrolysis technology application can be a good basis for further research of transferring modern engines to the pyrolysis gas fuels. [ABSTRACT FROM AUTHOR]

The article is dedicated to the overview of opportunities of pyrolysis gas application as an alternative kind of fuel in industry and household. The pyrolysis phenomenon itself was discovered in the end of XVII сent., while the various metods of pyrolysis gas application as a fuel for recently invented internal combustion engines were successfully used from the late XIX сent. In automotive, marine and railway engines till mid ХХ сent. when large oil sources were discovered all over the World. However, the technology of pyrolysis gas application still exists nowadays and applied in a limited ways in different spheres, which is going to be analyzed in the article for discovering further research opportunities on this topic. [ABSTRACT FROM AUTHOR]

The contribution of excavated waste to waste management is multifaceted, including minimization, non-hazardous disposal, access to useable land resources, improved waste management techniques and public environmental awareness, consistent with recent circular economy initiatives. Pyrolysis can be converted into tar, pyrolysis gas and char with recyclable utilization, enriching the application of pyrolysis technology in the field of excavation waste. In this study, the pyrolysis system includes horizontal tube furnace, gas collection device and Micro GC. The excavated waste was pyrolyzed at a temperature of 500∼900 °C with a heating rate of 10 °C/min. Pyrolysis gases include H 2 , CO, CO 2 , CH 4 , C 2 H 4 , C 2 H 6 and C 3 H 8. Pyrolysis was divided into four stages, the main decomposition range is 230∼500 °C, with a weight loss rate of 68.49% and a co-pyrolysis behavior. As the temperature increases, the tar and char decreased and the gas production increased significantly, and the pyrolysis gas reached 47.02% at 900 °C. According to Pearson correlation coefficient analysis, the generation of H 2 and CO is positively correlated with temperature. Therefore, the target products can be influenced by changing the parameters, when considering the practical utilization of the excavated waste pyrolysis products. On this basis, the prediction models were built by polynomial fitting method. This model can reduce the experimental exploration cycle, reduce the cost, and accurately predict the pyrolysis gas, which has practical guidance for the application of pyrolysis industry, and provides a theoretical basis for the resource recycling and energy recovery of landfill. [Display omitted] • Thermogravimetric properties and kinetic analysis of excavated waste were studied. • The high temperature favors the production of H 2 /CO, and hinders the CO 2 /CH 4. • The correlation of pyrolysis gas generation was analyzed by Statistical method. • The gas prediction model was built using a polynomial fitting method. [ABSTRACT FROM AUTHOR]