Donald W. Shepherd
Caldwell Energy Company
Louisville, Kentucky, USA
The output of combustion turbines operating on syngas is greatly reduced due to the lower heating value of the fuel. To recoup some of that lost power, inlet cooling with fog and patented wet compression has been applied to a General Electric combustion turbine in China. This is a first of its kind application and this paper will detail the specifics relative to the design and impact on the combustion turbine.
The combination of inlet cooling with fog and wet compression increases the capacity of a combustion turbine (CT) by injecting water droplets into the inlet to evaporative cool the air and purposefully injects additional fog into the compressor inlet (AKA – overspray, high fogging or super saturation) to further cool the inlet air and intercool the combustion turbine. The increase in capacity is threefold: denser inlet air, reduction in compressor work, and ability for additional firing in the combustor, in addition to the overall increase in mass flow through the turbine.
This paper focuses on the unique obstacles overcome in applying this technology to a syngas combustion turbine. It will detail the thermodynamic benefits of inlet cooling with fog and wet compression, the risks associated therewith, the steps that were taken to integrate and validate the system at a recent installation, and performance results of the system application on a GE combustion.