WEBAbstract. Coal pyrolysis is important since it is the initial step in most coal conversion processes and is the step which is most dependent on the properties of the coal. In liquefaction, pyrolysis controls the initial yield of soluble products, their molecularweight distribution, and the competitive yield of gas species.
WEBAiming at the optimization of the dust removal process in the polygeneration system of circulating fluidized bed (CFB) combustion/coal pyrolysis, a granular bed filter (GBF) is applied to the coal pyrolysis by solid heat carrier. By carrying out labscale experiments with a movingbed pyrolyzer, the GBF model proposed by C. Tien et al. was used to .
WEBJan 1, 2021 · The scientific and industrial community's interest in the pyrolysis process has increased significantly over the past few decades. The amount of scientific documents published on pyrolysis using either coal or biomass as feedstock for different years is shown in Fig. can be observed that research in both coal and biomass pyrolysis .
WEBDec 1, 2023 · Thermogravimetric analysis (TGA) is widely used to investigate the kinetics of processes in the condensed (, liquid or solid) phases, 5 such as the pyrolysis of polymers, nanoparticles, and other materials, 6, 7 combustion and pyrolysis process of fossil fuels, 8 and the copyrolysis process of various materials and fuels, 9 due to its .
WEBOct 1, 2019 · Compared with traditional pyrolysis processes, the integrated process of CO2 reforming methane and coal pyrolysis (CRMP) can obviously improve the tar yield. However, the structural information ...
WEBDec 15, 2023 · During coal pyrolysis, the heating and quenching procedures were iterated five times within a duration of 1000 ps. ... Integrated process of coal pyrolysis with steam reforming of ethane for improving the tar yield. Energy Fuel, 32 .
WEBDec 1, 2020 · In the alytic hydrogenation process, the addition of free radical scavengers can stabilize coal pyrolysis free radicals to form small molecular products and avoid condensation of primary volatiles, thereby improving tar quality [2].
WEBMar 1, 2024 · To characterize the pyrolysis process of Zhundong coal, an updated version [50] of the CRECKS model [55] from Politecnico di Milano (PoliMi) was successfully employed. Detailed information about the CRECKS model is available in Refs. [50, 56].This CRECKS model extended for Zhundong coal comprises 23 species and 43 reactions .
WEBOct 1, 2023 · Underground coal gasifiion (UCG) is a promising technology which insitu converts coal into fuel gases through controlled chemical reactions. In order to precisely control coal pyrolysis and increase the char yield, it is vital to understand the influences of operating factors such as heating rate and pressure, on coal pyrolysis.
WEBOct 1, 2022 · The coal pyrolysis can be divided into three stages, drying stage, depolymerization and decomposition stage and polycondensation stage [42]. It can be seen from Fig. 11 that pressure has different influences on coal pyrolysis process at low (600 °C) and high (800 °C) temperatures. Download : Download highres image (244KB)
WEBOct 1, 2023 · The free radical mechanism is the dominant coal pyrolysis mechanism. The process starts with the cracking of macromolecular structures of organic matter, involving numerous simultaneous reactions, including cleavage reaction, condensation reaction and interface reaction [22], [23]. Fig. 1 illustrates the formation mechanism of char, divided .
WEBJul 1, 2022 · To evaluate the kinetic parameters during the copyrolysis of the coalbiomass blends, the CoatsRedfern method with thirteen g(α) was implemented. The Arrhenius plot for thirteen g(α) was plotted between ln[g(α)/T 2] vs 1/T which results in a straight, if the correct g(α) is employed, the plot gives a straight line with .
WEBNov 1, 2018 · Transformation of sulfur and nitrogen and properties of pyrolysates (semicoke, retorting gas, coal tar) during Shenmu coal pyrolysis were investigated using XPS, TGFTIRMS, GC–MS and GCPFPD. The results showed that total sulfur content in the semicoke decreased gradually and turned to sulfate sulfur and thiophenic sulfur with .
WEBOct 15, 2014 · These works give us a useful insight for investigating the mechanism of coal pyrolysis, but in order to control the pyrolysis process and call for highquality gas and tar products, more microscopic details of chemical reactions during coal pyrolysis, especially for the generation process of key gas (CH 4, H 2, CO, and CO 2) and liquid products ...
WEBMar 23, 2023 · The coal pyrolysis is a fundamentally important process since it involves a set of chemical reactions, which play key roles in most coal conversion processes, such as coking, liquefaction, hydrogenation, gasifiion and combustion. ... Coal softening is a consequence of both physical melting process and pyrolysis breakdown of the coal .
WEB1980. 82. PDF. Coal partial hydropyrolysis process aims at coproduction of high yield of light oil and synthesis gas from a low rank coal under a mild hydropyrolysis condition. The characteristic of this process is in the hydropyrolysis reactor composed of the reformer and gasifier. So far, in order to evaluate the process concept a small ...
WEBMay 1, 2024 · The volatile compounds released during coal pyrolysis evolve in a process that can markedly change the surrounding environment, chemical structure, surface morphology and porosity of the coal particles [6], and have notable effects on the formation of certain pollutant precursors (such as NO X, SO 2 and soot), and high valueadded .
WEBJan 15, 2023 · Due to the complexity of coal pyrolysis, there is a challenge to disclose the reaction mechanism of pyrolyzate. So far, the molecular dynamics (MD) based on reactive force field (ReaxFF) is an effective method to study the reactive mechanism of complex compound, and has been widely used in coal pyrolysis process [20]. The ReaxFF .
WEBApr 1, 2020 · An experimental investigation on heating rate effect in the thermal behavior of perhydrous bituminous coal during pyrolysis. Perhydrous bituminous coal has multipurpose industrial appliions established by its distinctive thermal behavior. The Huainan coalfield in China has a large volume of these types of coals...
WEBNov 6, 2019 · Therefore, FTIR spectroscopy was employed to analyze the gas generated during the pyrolysis of coal under anaerobic conditions, and the corresponding results are shown in Figures 4(a)–4(f). For all samples, the main gases produced during the pyrolysis process were CH 4, CO 2, and water vapor. This result is consistent with the results of .
WEBJul 20, 2023 · Lowrank coal (LRC) pyrolysis assisted by biomass can realize the clean and efficient conversion utilization of LRC. The gas and tar characteristics obtained fr ... of apple branch (AB) and LRC at different stages were studied with TGFTIR and PyGC/MS. It was found that the copyrolysis process could be divided into four stages, and the .
WEBJan 15, 2020 · Therefore, understanding the specific effects of functional groups is of great significance for the further study of coal pyrolysis process. However, the lack of direct online observation and indepth mechanistic analysis on the influence of functional groups during the pyrolysis process lead to the difficulty in unified understanding on the ...
WEBAug 15, 2023 · The molecular model of tarrich coal was constructed by combining experimental characterization and theoretical calculations. • The molecular model was validated by calculating FTIR and 13 C NMR spectra with quantum chemistry.. Complex systems containing multiple molecules were constructed, and the pyrolysis process .
WEBApr 1, 2022 · The release characteristics of biomass model compounds and coal in the copyrolysis process were deeply researched by the thermalmass spectrometer (TGMS). When the temperature reaches to 500 °C, the main pyrolysis products of microcrystalline cellulose and lignin are released. At the temperature higher than 900 °C, small .
WEBDec 1, 1988 · Newer developments in coal pyrolysis, like hydropyrolysis, use a reactive gas such as hydrogen in place of an inert atmosphere. Pyrolysis or carbonization processes represent the second largest use of coal next to combustion. ... Various arc systems have been used to process coal, some such as the AVCO arc process have .
WEBDec 1, 2019 · Within this conversion process, the thermochemical reaction of coal is treated as a combination of low temperature pyrolysis and semicoke combustion/gasifiion [1], [2]. And the pyrolysis gas and tar are obtained as highgrade raw materials, while the semicoke can be used for power generation, gasifiion and .
WEBJan 1, 2023 · A lowrank coal pyrolysis coupled with gasifiion for DRI system is proposed. • Effects of the key parameters on CCHI process are optimized and analyzed.
WEBThe process of pyrolysis is widely used to break down organic substances. For example, the charring of wood (or the incomplete combustion of wood) that results in the formation of charcoal involves the process of pyrolysis. ... Coke can be obtained from coal (along with a wide spectrum of different compounds) via the process of pyrolysis. What ...
WEBNov 7, 2014 · A novel process of integrated coal pyrolysis with steam reforming of methane (CPSRM) was put forward for improving the tar yield. Two Chinese lignites were used to confirm the validity of the integrated process. At the investigated temperature range of 550–750 °C, CPSRM achieves the highest tar yield, total gas yield, and C2 + C3 gas .
WEBNov 1, 2018 · By adding ash, ash/natural dolomite and ash/modified dolomite to the coal pyrolysis process, the content of Hg 0 in pyrolysis gas decreased to %, % and %, respectively. The research is able to offer the theoretical foundation for mercury contaminants' removal and process optimization of the step conversion technology.
WEBOct 1, 2023 · The two key factors that significantly impact coal pyrolysis are its structural composition and the medium in which it is carried out. In this study, effects of acid pretreatment (AP), hydrothermal pretreatment (HTP), and acidhydrothermal synergistic pretreatment (APHTP) on Shenfu Lowrank coal (SF) structure were investigated.
WEBOct 6, 2016 · Lowrank coal (LRC), as a conventional fossil fuel, has wealth of reserves and a wide range of distribution around the world, and pyrolysis is thought to be an easy way for clean and efficient conversion of LRC. In this chapter, the characteristics and world's reservation of LRC are introduced. Then, the chemical reactions and product .
WEBDec 1, 2023 · In the process of coal mining, washing and utilization, a huge amount of coal gangue (CG) is produced, which has become the largest solid waste in China. ... [14] et al. discussed the influence of alkali metal compounds on the pyrolysis process of CG, and the results showed that high alkali metal content could reduce the initial precipitation ...
WEBAiming at the optimization of the dust removal process in the polygeneration system of circulating fluidized bed (CFB) combustion/coal pyrolysis, a granular bed filter (GBF) is applied to the coal pyrolysis by solid heat carrier. By carrying out labscale experiments with a movingbed pyrolyzer, the GBF model prop
WEBJan 1, 1992 · Coal pyrolysis: Experiments, kinetic rates and mechanisms Author links open overlay panel Peter R. Solomon ∗, Michael A. Serio ∗, Eric M. Suuberg † Show more
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