Retrofitting the combined-cycle producing electric power and desalted seawater to include district cooling in GCC

Abstract

AbstractRecent installed power plants (PP) in Qatar and other Gulf Co-operation Countries (GCC) are using combined cycle (CC). The CC cycle consists of gas turbine (GT), heat recovery steam generators (HRSG), and steam turbine (ST). In these plants, GTs produce electric power (EP) and its exhaust hot gasses operate the HRSG to generate steam. The steam is supplied to ST that generates more EP, and its extracted (or discharged) steam is directed to thermally operated desalting plant (DP), e.g. multi stage flash (MSF) or multi-effect thermal vapor compression (ME-TVC) producing desalted seawater (DW). A plant producing both EP and DW is called co-generation power desalting plant (CPDP). The used ST type is either extraction condensing steam turbine or back-pressure steam turbine. The MSF or ME-TVC consumes about 280 MJ/m3 thermal energy, besides pumping energy of 4 kWh/m3 for MSF or 2 kWh/m3 for ME-TVC systems. Because of high consumed energy, the MSF and ME-TVC systems have to be substituted by the much mo...