KINETICS OF GASIFICATION OF CZECH BROWN COALS

Steam gasification kinetics of Czech brown coals of different rank was studied, using a differential flow reactor at 800-950-degrees-C and 0.2-1.6 MPa. As gasification agent a mixture of steam and hydrogen was used. with a hydrogen content of 28.6 or 16.7%. The gasification rate was determined from the time-dependence of product concentrations in the dry outlet gas. The kinetics was evaluated on the basis of a model describing gasification rate by the product of two independent terms, one depending only on carbon conversion and expressing development of active sites during gasification, and the other depending on temperature, pressure and gas composition.