Exhaust Gas Cooling in an Open-Cycle Gas Turbine in Switzerland

An air injection system and a downstream ammonia injection grid were designed and verified using CFD simulations. The exhaust gases from the gas turbine, initially at 540 °C, were cooled to the catalyst operating temperature of 390 °C.

A key challenge was meeting the strict requirements for gas velocity, temperature, and ammonia distribution upstream of the catalyst layer. These conditions had to be achieved despite a highly rotating exhaust gas flow, a steep diffuser, and limited available installation space. 

Following optimization, an effective arrangement of installations was developed, enabling full compliance with the catalyst distribution requirements.