Pulverized coal pyrolysis

Irfan, M.F. 2009. Research Report Pulverized coal pyrolysis gasification in N2/O2/CO2 mixtures by thermo-gravimetric analysis. Novel Carbon Resource Sciences Newsletter, Kyushu University, Fukuoka, Japan, Vol. 2, pp. 27-33. 

Lowndes et al. [91] used the commercial CFD model Fluent to simulate flame spread along a conveyor belt. Fluent, at the time this modeling was conducted, did not contain a conventional pyrolysis model in the sense that is normally implied in the fire literature. Instead, the authors adapted a discrete phase model, which is intended to simulate the combustion of pulverized coal. 

Solomon, P. R., and Serio, M. A., Evaluation of Coal Pyrolysis Kinetics, in Fundamentals of Physical Chemistry of Pulverized Coal Combustion, J. Lahaye and G. Prado (Eds ), Martinus Nijhoff Publishers, 1987. 

More recently, the CSIRO work has included studies of chars produced from the flash pyrolysis of subbituminous coals. This work has formed part of a major project to develop the flash pyrolysis process of converting coal into oil ( ) in which pulverized coal... 

In this paper the combustion reactivities of four flash pyrolysis chars are compared with the results for chars produced from low and high-rank coals under conditions simulating pulverized-coal combustion, for anthracite and semianthracite, and petroleum coke. Reactivity is expressed as the rate of combustion of carbon per unit external surface area of the particle, with due correction being made for the effect of mass transfer of oxygen to the particle. 

Yu, J., Harris, D., Lucas, J., Roberts, D., Wu, H., and Wall, T. Effect of pressure on char formation during pyrolysis of pulverized coal. Energy Fuels, 2004, 18, 1346. 

Experimental data of coal pyrolysis in a sand fluidized-bed reactor indicate that it is possible to extract considerable amounts of hydrocarbons from caking coal by a rapid heating and subsequent cracking in the vapor phase. This is done by flowing pulverized coal into a fluidized... 

The combustion of pulverized coal particles can be broken down into two main processes (a) evolution of volatiles (pyrolysis) and their subsequent combustion and (b) heterogeneous combustion of the solid residue. Questions at issue in these two processes are (a) What is the effect on pyrolysis yield of the rate of heating, which in pulverized coal systems can reach 104°C/sec and (b) what are the reaction order and activation energy of the subsequent char burnout Answers to these questions can affect approach to design of both normal pulverized coal boilers and char... 

With the large captive particles, the particles only pyrolyzed, with simultaneous combustion of volatiles and formation of a char particle. When pyrolysis stopped, char combustion started. This sequence of events is well known for large particles—particularly lumps on a grate— and it was also the accepted mechanism for small particle combustion of pulverized coal (about 1-100 /xm). With very small particles, the rates... 

Combustion of scrap tires and, for that matter, any pulverized fuels including coal, coke, or biomass proceeds in two phases. First, the organic solid polymer undergoes pyrolysis upon reaching a temperature of about 250-300°C to release the volatile matter and solid residue (char). Second, these volatiles and char undergo combustion (Figure 6.3). 

First, selected coals are blended and pulverized. Some coal tar is added for appropriate bulk density control. The blended coal is charged into the coking chambers by a charging car, which moves on the roof of the coke oven battery in a longitudinal direction, and the chambers are filled from the top in a specific sequence via charging holes. The brick walls of each coking chamber are heated up to about 1100 °C and, in the course of time, the coal charge is heated and transformed by pyrolysis... 

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