โ Scribed by Girard A. Simons
No coin nor oath required. For personal study only.
Volatile transport during pyrolysis is described. Volatiles are generated at the walls of the pores and are transported through the pore tree via both diffusion and convection. The model is parametric in the intrinsic pyrolysis rate k and suggests that for k in excess of I s -1,100-~m-diameter particles will experience internal pressures in excess of 103 aim. Since a large fraction of the volatiles experience this limiting pressure, vast potential exists for secondary chemistry within the pores. Several phenomena are identified which may limit the gas pressure within the porous solid. The limiting pressure is represented parametrically by Plimit' It is shown that the fluid mechanical transport of the volatiles decreases monotonically with decreasing values of Ptimit and the devolatilization rate is significantly reduced by the fluid transport.
๐ SIMILAR VOLUMES
A theory of pore evolution in nonswelling coal is presented which describes the development of the pore structure during pyrolysis. The pore evolution theory treats the rate of increase of porosity (dO~dO as a bulk kinetic parameter and identifies the corresponding rate of growth of each pore in the