The detailed mathematical description of technological processes is a decisive prerequisite for an optimal operation and design of the respective plants. In line with this objective a mathematical model for the high-pressure gasification of solid fuels in the charged layer is presented which permits the quantitative description of the static behavior of the generator. With due consideration of the partial processes taking place in the high-pressure gasifier, the paper deals with the parameters of reaction kinetics and of the transfer of matter and energy which are necessary for developing the model of a fixed-bed reactor. To obtain a practicable model, simplifications are needed which concern the gasification, degasification, and drying processes. They are dealt with individually. For calculating the concentration and temperature profiles for the solid and gas phases along the gasification bed height, a system of differential equations was obtained which was supplemented by some algebraic equations. The modified Euler method was used for the solution. The algorithm for the solution of the system was programmed in Fortran. A Tesla 200 computer was used for calculations.

Methane combustion in the presence of various types of perovskites supported on ceramic foams has been studied with respect to the CO and NOx formation. The effect of the catalyst composition and of the air-to-methane ratio on the CO and NOx concentration has been evaluated for different burner capacities.

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Catalytic combustion of methane has been studied in the presence of catalysts supported on ceramic foams. Low concentrations of NOx (in the range of 5 - 50 mg m-3) were observed with all catalysts used. Concentrations of CO depended strongly on the type of the catalyst, its composition, methane throughputs and varied from 4 400 to 0 mg m-3. Minimum CO concentration (0 - 8 mg m-3) was gained with 0.04% Pt on ceramic foam modified with both alumina Al2O3 and lanthana La2O3.

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