A Predictive Model for Coal Coking Based on Product Yield and Energy Balance

A series of experimental coal pyrolysis studies were conducted to define the parameters of a kinetic model to enable complete mass and energy balances by identifying basic process products. The developed model determines the chemical enthalpy of pyrolytic reactions, making it possible to determine the share of exothermic conversions in the coking process. To validate the model, a series of experimental pyrolysis tests of coking coals used in the coke plant and their blends were conducted, including TGA, retort, and industrial coke oven scale. Despite significant differences in the chemical composition of various coal types, element balancing allowed detection of the difference in product composition and the heat effects of the chemical conversion of such a complex substance as coal. Analysis of the heat effects of pyrolytic coal decomposition indicates substantial variability. In the first coking period, there are endothermic reactions; in the second, exothermic reactions occur. Average heat effect of the pyrolytic reaction for whole coking period is exothermic and, depending on the coal type, ranges from −5 to −50 kJ/kg. The model herein can be used to analyze many other pyrolytic processes because it also takes into account the heating rate.

Tratamiento de la biomasa lignocelulósica mediante la pirolisis lenta y a baja temperatura para la producción de biocombustibles

Transforming residual biomass into valuable energy compounds is important due to the problems of the energy crisis and environmental pollution, the biofuels produced are a valuable substitute for liquid or gaseous fuels for the transport sector becoming a cheap raw material, It reduces the concentrations of polluting gases, disposal problems and greenhouse effect emitted into the atmosphere. The object of study was the processing of residual biomass, to determine the optimal conditions of slow and low temperature pyrolysis to generate the highest volatile matter yield of lignocellulosic biomass; in addition to quantifying the Condensible Volatile Matter and the Non-Condensible Volatile Matter obtained from the pyrolytic reaction. According to D. Chiaramonti, et al., 2007, a higher liquid yield is obtained when the amount of volatiles is higher, the high MV content makes residual biomass a candidate with high potential for biofuel production, demonstrating that the highest yield of volatile matter during the pyrolysis the final temperature must be higher than 350 ° C, using a heating rate of 5 ° C / min, a residence time of 60 minutes and a particle size of 150 mc.

A Study Designed to Improve High-Temperature Thermal Stability of SiC Fiber

In a high-temperature environment, the pyrolytic reaction of the SiC fiber destroyed the chain structure of the fiber and cause fiber apparent weightlessness, the surface and internal of fiber produce porous structure defects. In order to improve high-temperature thermal stability of SiC fiber that the reunion composite powder (CP) of perlite and nanozirconia was prepared by atomized granulation technology, and the CP is sprayed the surface of SiC fiber by plasma spraying technology. The SiC fiber was completely ablation at 1200°C for 3h. On the contrary, the spraying CP of fiber is not affected, showing favorable high-temperature stability. The surface appearance of the fiber was analyzed by means of SEM, and the flame temperature Spray Watch.

Effects of Gangue on Pyrolysis of Municipal Solid Waste

To investigate the effects of gangue on pyrolysis of municipal solid waste (MSW), pyrolysis of MSW with gangue has been conducted by TG and fixed-bed reactor, respectively. The effect of gangue on pyrolysis product yields and compositions of gaseous products was investigated and the obtained results were compared with similar experiments without gangue. It was shown that gangue can improve the pyrolytic reaction of MSW, reduce the char yield, increase the liquid yield. And influences of gangue on yields of H2, CO, CH4 and CO2 were more apparent, the yields of H2, CO and CO2 with gangue were improved 12.5%, 11.8% and 175%, respectively, conversely, the yield of CH4 was reduced 15.4% compared with no gangue.