The heart of the cogeneration plant is the ABB GT10A Combustion Turbine Generator set. The nominal turbine output is 21 MW under nominal ISO conditions. The electrical heat rate is 11,400 BTU/kWh (LHV), maximum exhaust temperature is approximately 1050° F, and exhaust flow is approximately 628,000 lbm/hr. Manufactured and engineered by ABB STAL AB, Finspång, Sweden, the turbine is of an industrial design (as opposed to an aeroderivative) that has been adapted from an early Sulzer design.
Perhaps the most important aspect of the turbine is its use of the ABB EV (EnVironmental) combustor. This design uses a premixed, swirling combustion flow to generate low NOx levels on both gas and liquid fuels. In addition to the EV combustor, the turbine makes use of water injection into the combustion zone to cool the flame. This reduces the thermal NOx levels by cooling the flame to approiximately 2300° F under nominal condtions. Developed with contributions from Professor (Emeritus) Janos Beér from the Department of Chemical Engineering, this combustor design allowed us to receive an environmental permit from the Massachusetts Department of Environmental Protection and proceed with the project.
This page offers at the moment some general pictures of the unit, as well as some nominal performance information.