GB884789A - Improvements in or relating to gas turbine plant - Google Patents

Abstract

884,789. Gas turbine plants. POWER JETS (RESEARCH & DEVELOPMENT) Ltd. Oct. 7, 1960 [Oct. 8, 1959], No. 34177/59. Class 110 (3). A gas turbine plant comprises compressor means the output of which is divided into two streams, one stream passing to a first heatstoring element in which it is heated, combustion means to receive the other stream, turbine means fed by the combustion chamber, a second heat-storing element to receive at least a part of the exhaust from the turbine means, valve means for intermittently interchanging the flow of the two streams through the heat-storing elements and heat exchange means to receive heat from the exhaust gases from one of the heat storing elements and to heat the whole output from the compressor means. An axial flow compressor 1 discharges through a heat exchanger 5 to an air turbine 7. The exhaust of the air turbine 7 is divided into two branches, one branch 9 leading to a first heat-storing element in the form of a Cowper stove 10 and the other branch communicating with a combustion chamber 12. Fuel for the combustion chamber is blast furnace gas supplied by a gas compressor 14 discharging through a heat exchanger 16. In practice, the compressor 14 is on the same shaft as the air compressor 1 and air turbine 7. The combustion chamber 12 feeds a gas turbine 17 which discharges through a twoway valve 20 to a second heat-storing element in the form of a Cowper stove 24. The combustion chamber of the Cowper stove receives blast furnace gas from the compressor 14. An exhaust duct 33 from the Cowper stove 24 leads to a second two-way valve 26 and to the hot pass of the heat exchanger 16. The valve 20 is connected to the valve 26 through duct 25. Duplicate ducts lead to each Cowper stove to permit intermittent interchange of the gas flows. The valves 20, 26 allow a supply of exhaust gases to the heat exchanger 5 whilst the interchange of the flows between the two Cowper stoves takes place. In a modification, Fig. 2 (not shown), the output of the compressor 1 is divided upstream of the turbine 7. In a further modification, Fig. 3 (not shown), the valves 20, 26 are omitted and the exhaust gases drawn through the Cowper stove 24 by an induced-draught fan which may have variablespeed drive. The air turbine 7 may be omitted. The valves 20, 26 may be used to divert a variable portion of the exhaust gases to the Cowper stove that is being reheated.