DESIGN ASPECTS OF LARGE COAL FIRED POWER PLANTS WITH SUPERCRITICAL PARAMETERS

摘要

Thermal power stations of 1000 - 2000 MW capacity, at present, are mostly based on 500 MW units with sub-critical parameters. Units of larger size and supercritical parameters are under consideration of power planners for quite sometime. Power plants of 2000 MW and higher capacities are proposed by some utilities and IPP's. For these, 660 MW units with supercritical parameters can be an alternative. This paper analyses the design aspects of power plants with supercritical parameters as compared to sub-critical parameters. The cycle configuration and parameterization aspects of such plants are discussed. Cycle arrangements with and without 'heater above reheat point' are analyzed and compared based on techno-economic considerations. Issues involved in design and sizing of power cycle equipment are highlighted and compared with sub-critical units. The impact of these equipment on plant utility requirements and facilities is given. Layout data for 2000 MW sub-critical and supercritical power plants is compared.