Split stream boiler for combined cycle power plants
OwnerIvan G. Riceinventor
Life of this patent
Estimating the term…
Abstract
A process and equipment for generating useful power comprising a special split stream heat recovery boiler 108 in combination with a gas turbine 20 and a steam turbine 80 to form a combined cycle. A steam-injected gas turbine 20 and alternately a condensing steam turbine 116 may be utilized. A topping high temperature and high pressure topping steam turbine 80 optionally may be included. Chemical heat recuperation via natural gas reformation may be incorporated within the boiler 108 to increase cycle efficiency further and to lower NOx formation without excess CO. The heat recovery boiler 206 yields increased efficiency and power output heretofore unexpected for the combined cycle compared to conventional combined cycle equipment.
Claims25
A gas stream heat recovery boiler for recovering heat exhaust from at least one combustion gas turbine to drive a load, comprising:
- at least one air compressor;
- at least one combustor receiving air provided by said at least one compressor;
- at least one gas expansion turbine for expanding gas provided by said at least one combustor and for providing first and second separate exhaust gas streams flowing downstream through first and second steam generators, each steam generator having at least one economizer for heating water provided by a water source and at least one evaporator for converting water to steam;
- a supplementary fired superheater upstream of the first steam generator, the first exhaust gas stream passing through the supplementary fired superheater, then through the first steam generator;
- and
- the second exhaust gas stream bypassing the supplementary fired superheater, then passing through the second steam generator, the first and second steam generators configured such that steam flow generated by the first steam generator is combined with steam flow generated by the second steam generator, such that the temperature of the steam produced by the first and second steam generators is increased by heat from the supplementary fired superheater.
A process for generating superheated steam from exhaust heat from at least one combustion gas turbine to drive a load, the process comprising:
- providing first and second separate exhaust gas streams from said at least one combustion gas turbine;
- positioning a supplementary fired superheater and s first steam generator having a first economizer for heating a source of water and generating steam along the first exhaust gas stream;
- positioning a second steam generator having a second economizer for heating a source of water and generating steam along the second exhaust gas stream;
- while generating steam in said first steam generator and in said second steam generator, increasing the temperature of said first gas stream by supplementary firing fuel upstream of said supplementary fired superheater;
- superheating the steam generated by said first steam generator and said second steam generator in said supplementary fired superheater by extracting heat from supplementary fired fuel burned in said first gas stream wherein said steam generated by said first steam generator and said second steam generator is combined and said steam is heated by the supplementary fired superheater;
- and
- discharging superheated steam from said supplementary fired superheater.
Dependencies are inferred from the claim text.