| The gasification combined cycle power plant is a major alternative for the conversion of coal to electric power. Although the operation and control of a combined cycle power plant is complicated, it is warranted due to financial and environmental advantages. The objective of this work is to develop a mathematical and dynamic simulation model of subsystems of the combined cycle power plant in order to permit analysis of the dynamic behavior and control. In this work, fluidized bed reactors are considered for the pyrolysis and gasification processes.; Dynamic simulation models for the fluidized bed pyrolyser and gasifier were developed by Caram (10, 12) in 1979. The models are based on kinetic and transport rate processes, thermodynamic relations, and mass and energy balances. The simulation models, which are based on a specific integration system (DDS/2) have been modified for a more general context both for the process and the numerical techniques. The results are compared and justified.; A digitial computer program has been developed to compute the thermodynamic performance of the gas turbine; namely, the net shaft work output and thermal cycle efficiency. By using the result of these calculations, one is able to select the proper design parameters such as compressor pressure ratio, air flow, and turbine nozzle area.; Dynamic simulation model and control of the boiler - steam turbine has been developed. Transient behavior of the system resulting from a step change in fuel gas flow rate has been analyzed. Reponses of the system variables and estimates of the control parameters are reported for a step increase in fuel gas flow rate.; A pseudo steady state calculation has been made in order to estimate the compositions of the low Btu gas leaving the pyrolyser, the net power output, and the overall themal efficiency of the combined cycle power plant. These results are in good agreement with those reported in the literature. |
