POWER GENERATION SYSTEM, METHOD FOR CONTROLLING TEMPERATURE OF COMBUSTION GAS ENTERING HEAT EXCHANGER THEREOF, AND METHOD FOR CONTROLLING TEMPERATURE OF COMBUSTION GAS ENTERING HEATING MEDIUM HEATER OF POWER GENERATION SYSTEM

摘要

To suppress deposition of viscous KCl to a surface of a steam pipe constituting a superheater when combusting biomass fuel containing bamboos.SOLUTION: A power generation system 1 comprises superheaters 31-33 for superheating steam by combusting fuel in a combustion furnace, generates power by driving a steam turbine with superheated steam that is superheated by the superheaters 31-33, and/or provides thermal energy. The power generation system comprises: temperature measuring means 14 for measuring a temperature of combustion gas at an upstream side of the superheaters 31-33; exhaust gas re-circulation means 61 for returning exhaust gas which is passed through the superheaters 31-33 and cooled, to a clearance between a combustion furnace 11 and the superheaters 31 and 33 and re-circulating the exhaust gas; exhaust gas re-circulation flow rate control means 64 and 66 for adjusting a re-circulation flow rate of the exhaust gas by the exhaust gas re-circulation means 61; and adjustment means 90 for adjusting a controlled variable of the exhaust gas re-circulation flow rate control means in such a manner that a temperature of the combustion gas at an upstream side of the superheaters 31-33 is kept constant. The system uses biomass fuel containing bamboos as the fuel.SELECTED DRAWING: Figure 1