Two-phasic coal combustion in fluidized bed in pressure - possibilities for implementation of steam-gas cycle

A scheme of two stage fluidized combustion is proposed in order to increase the electricity production efficiency. The first combustion stage is performed in the reactor, where due to air feed less than the amount necessary for complete combustion. The output combustible components such as CO and H2 are fed in the gas turbine. In the combustion facility before the gas turbine these components burn out with the necessary air feed leading to a temperature increase to 1200-13000C. The study shows that it is technically possible to construct such an installation. The use of the lignite coal from 'Maritsa Iztok' requires additional desulfurization. The desulfurization in the pressurized fluidized boilers is lower than one in the conventional fluidized boilers. The flue gases contain more CaSO4 and CaS (CaSO4 increase for lower temperatures)