Feedwater heaters in Combined Cycle power plants
Feedwater heaters in Combined Cycle power plants
(OP)
Please advise as to why combined cycle power plants (incorporating gas turbines and steam turbines) do not need or use feedwater heaters in comparison to conventional(rankine cycle) plants which use feedheaters to optimise the quality of water entering the boiler.
Many Thanks.
Many Thanks.





RE: Feedwater heaters in Combined Cycle power plants
For HRSG's, I would think that the cost benefit analysis would probably not justify payback for the capital cost of purchasing and installing separate feedwater heaters in the cycle.
RE: Feedwater heaters in Combined Cycle power plants
Many thanks and appreciation for your help.
Regards
jgeorge747
RE: Feedwater heaters in Combined Cycle power plants
The FWH's in a standard steam cycle are a penalty to the process, notwithstanding the benefit that they accomplish as outlined by Metengr, in that the extracted steam is unable to continue down through the steam turbine and produce power.
There is enough energy available in the GT exhaust to heat the incoming feed water to what it needs to be without taking any steam away from the ST.
rmw
RE: Feedwater heaters in Combined Cycle power plants
You hit it on the head......an excellent response !!
The best and briefest explanation is "Why extract that steam from the turbine (with the large capital cost, water chemistry and other expensive issues) when there is still all that hot gas available ?
My opinion only !!!
MJC