Gas Turbine System with Interstage Cooling and Steam Injection Using Oxy-combustion

The intake air temperature influences the power output of a gas turbine. In order to control it, the paper considers the interstage air cooling by adiabatic humidification. Steam injection after the combustor is considered to control the flue gases temperature in the inlet section of the turbine. Both techniques are intended to increase the shaft work rate of the gas turbine. The first section of the paper studies the influences exerted by the intake air temperature and by the injected steam/air ratio on the flue gas temperature and composition. The second section tackles the analysis of the compression and expansion processes respectively, allowing the estimation of the shaft work of the turbine. The third section of the paper considers the opportunity of using oxy-combustion to increase the power of the turbine or to counterbalance the effect of the compressor power consumption increase due to high intake air temperatures.