Control system for gas turbine generating power, has three-way valve and heat exchanger for warming fuel gas entering combustion chamber to maintain constant Wobbe number

摘要

Two separate gas supplies with different Wobbe numbers pass through reducing valves (4) and supply lines (3) to a gas mixer (5). The line (2) carrying the mixed gas passes a device (14) for measuring the Wobbe number and a three-way valve (8). The temperature of the incoming gases may be approximately 15 degrees C and the Wobbe numbers may be between 12.0 and 16.0 kWh/Nm3. Mixed gas passes from the three- way valve to a first heat exchanger (6) receiving heat from a second heat exchanger (10) via an intermediate circuit (9). The first heat exchanger is held at a temperature of 125 degrees C. A bypass line (7) recirculates some gas to the three-way valve. There is a further gas mixer and a temperature regulator (17) before the entry into the combustion chamber (1).