Coal pyrolysis is a critical step of coal thermal conversion, impacting the downstream utilisation of coal, such as combustion and gasification. The understanding of this complex process plays a crucial role to predict the products, operation optimisation and reactor design. Indian coals typically have 2552% (as received) ash yields.
During the actual pyrolysis process, the physicochemical structure of coal will be decomposed with the generation of products, such as tar, char, and gaseous compounds [21], [22].Generally, the coal pyrolysis process consists of primary devolatilization reactions and subsequent secondary reactions [23], [24].In this work, to combine the mass transfer with pyrolysis kinetics more conveniently ...
Pyrolysis, as a process technology, has received considerable attention from many researchers because it is an important intermediate stage in coal conversion. Reactions parameters as the ...
The conventional coal gasification and steam methane reforming processes for hydrogen production are undesirable due to the huge CO 2 emissions. A cleaner technology based on natural gas that has received special attention in recent years is methane pyrolysis. ... Iron and carbon catalysts are therefore the best choice to industrialize the ...
Two wellknown products created by pyrolysis are a form of charcoal called biochar, created by heating wood, and coke (which is used as an industrial fuel and a heat shield), created by heating coal. Pyrolysis also produces condensable liquids (or tar) and noncondensable gases. Process
Thermocatalytic pyrolysis of waste packaging plastic was investigated in a semi batch reactor. Spent aluminum hydroxide nanoparticle derived from the electrocoagulation of arsenic and fluoride containing synthetic ground water was developed into catalyst through combined thermal treatment and metal impregnation process. Nickel, iron, zinc, copper, and molybdenum were separately doped on the ...
The pyrolysis of pulverized coal takes only a few hundred milliseconds, and the coal combustion/pyrolysis process produces carbon black quickly. The formation of carbon black particles mainly includes their initial nucleation, growth process, fusion, and polymerization [7]. The coal tar generated by the primary pyrolysis of coal contains a ...
Pyrolysis polygeneration technology is a good way to realize clean and efficient utilization of lowrank coal and heat carrier is a key factor. Aspen Plus is used to establish lowrank coal pyrolysis staged conversion polygeneration technology with semicoke heat carrier based on dualfluidized bed (CPSCPCDFB), which couples with ultrasupercritical semicoke powder furnace for power generation.
For the coal pyrolysis process, unstable sulfur compounds will decompose, generate sulfur radicals and release as sulfurcontaining gases, this becomes the main pathway for sulfur removal. Coal properties, minerals and sulfur forms in coal, and pyrolysis conditions such as temperature, atmosphere, and the mass transfer, are the main factors ...
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, gasification and combustion. ... Coal softening is a consequence of both physical melting process and pyrolysis breakdown of the coal matrix ...
Pyrolysis is the thermal decomposition process of coal, where the coal is heated in the absence of oxygen to produce carbonaceous char, oil, and combustible gases. Unlike combustion, the pyrolysis technology is an endothermic process, where thermal energy required driving off moisture and volatile matter ( Das et al., 2016 ).
Coal pyrolysis is generally performed in atmospheres without oxygen and at temperatures below 650 °C for producing pyrolysis liquid and gas. To support the development of a new twostage gasification process integrating a fluidizedbed pyrolyzer and a downdraft fixedbed gasifier, this paper investigated the coal pyrolysis in atmospheres containing oxygen and steam and at temperatures up to ...
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 the ...
The whole treatment process of CPW is shown in Fig. 1. The coal particles are introduced into the drying unit to provide steam for CLG and the remaining dry coal enters into the pyrolysis unit to produce pyrolysis gas and char. The CPW is generated during cooling and separation of pyrolysis gas. The dotted red line represents the impact of CPW ...
Coal pyrolysis is a process of multistage transformation using the composition and structural characteristics of coal to replace oil and gas resources (Qu et al., Citation 2010). In the process of coal pyrolysis, the pyrolysis gas is doped with particulate coal owing to combustion insufficiently. The filtration system is part of the coal ...
Depolymerization of coal increases the tar yield in coal pyrolysis and enhances the thermoplasticity of the coal, which makes coal more favorable for producing coke and other valueadded products like graphite electrodes, carbon fiber, aromatic chemicals, etc. In this study, the authors have proposed a novel coal depolymerization method that combines the oxidation reactions by molecular oxygen ...
(1), where m 0, m t were the initial mass of coal and the mass at a given time during the pyrolysis process, respectively. And m ∞ was the final mass of coal sample when the pyrolysis process was completed. (1) α = m 0m t m 0m ∞. The heating rate β was defined as Eq. (2). (2) β = d T d t
1. Introduction Pyrolysis is an effective and mild coal conversion process. The polygeneration technology based on coal pyrolysis can produce many valuable products such as highcalorific pyrolysis gas, upgraded coal tar, and clean solid fuel char or coke, which will realize multilevel efficient utilization of coal resources. 1,2 The products of coal pyrolysis are affected by various factors ...
More importantly, during the pyrolysis process of 3560 mesh coal, the largest amount of coalchar and the smallest amount of coaltar are not only obtained, but highquality syngas is also obtained. Through the characterization of coaltar, it is found that coaltar is mainly composed of aromatic compounds, and the content can reach more ...
Coal SJC, coal WJG, coal ZJM, and coal HCG were selected to investigate the pyrolysis kinetics of northern Shaanxi coals. TG and DSC experiments of four coals were carried out with a synchronous thermal analyzer at heating rates 5, 10, 15, and 20 C/min, respectively. The pyrolysis characteristics were described by thermogravimetric data, and the kinetic parameters were calculated by Flynn# ...
The copyrolysis process of coal and biomass was simulated using Aspen Plus V11 software. The reliability of the model was verified by comparing the distribution of copyrolysis products under different raw material ratios with the experimental and simulated values. At last, through the economic analysis of the investment in plant construction ...
The coalbased pyrolysis process faces so many challenges based on the production and consumption and also the limited resources, low efficiency and higher emissions. Biological origin. There has been a lot of studies on the feedstocks of biological origin used in microwave pyrolysis. Biological origin here refers to the feedstock having a ...
Also, we investigate the catalytic activity of the catalysts in coal pyrolysis process. 2 Methodology and Experiments. Preparation of NiCo Ternary Molten Salt Crystal Catalysts. The molten salt crystal synthesis method has been proposed by Rockwell International Corporation in 1965 . And it is an efficient method for the preparation of ...
Production of synthetic crude oil from coal using the Toscoal pyrolysis process. Conference Cortez, D; LaDelfa, C Proc., Intersoc. Energy Convers. Eng. Conf.; (United States) This paper presents the results of a recent feasibility study of the Toscoal process for recovering oil and gas from coal prior to combustion in power plants. Conceptual ...
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