USE OF SALINE WATER FOR INCREASE THE TURBINE OUTPUT POWER BY CONNECTION OF DIRECT CONTACT MEMBRANE DISTILLATION (DCMD) UNIT TO A STEAM INJECTED GASTURBINE (SIGT)

steam injected gas turbines (SIGT) have been proposed to increase efficiency and specific work of gas turbine engines. These cycles allow to recover exhaust heat for re-use within the gas turbine plant and are an attractive alternative to combined cycles for small and middle-range industrial power plants. In a SIGT, steam is produced in a heat recovery steam generator (HRSG) using the exhaust heat of the gas turbine stack and is then injected into the gas turbine combustion chamber. Camporeale and Fortunato (۱۹۹۶). However, the large water consumption is a major disadvantage of this system, which restricts the use of the plant, especially in water-short areas. For example, A LM۵۰۰۰ STIG™ plant commercialized by General Electric, for instance, consumes about ۲۹ t/d water per MW power output (۱۴۵۰ t/d water with a power output of ۵۰.۷ MW) when running under a full STIG pattern. De Paepe and Dick (۲۰۰۱). Connecting desalination units to the SIGT has been proposed as an idea for the required water supply. For example, Cerri and Arsuffi (۱۹۸۸) proposed a multi-stage flash (MSF) unit driven by exhaust gas heat of turbines for producing demineralized water from seawater for a STIG cycle. The connection of multi-effect thermal vapor compression (METVC) to STGT was modeled and analyzed by Wang and Lior (۲۰۰۶). They have indicated the good synergy, of this connection in fuel utilization, operation, and design flexibility. However, one of the desalination methods that its ability has not yet been investigated to connectto a power plant, is membrane distillation (MD). This technology is a non-isothermal membrane separation process that vapor of volatile component transmitted through a no wetted porous hydrophobic membrane. In this process, the vapor pressure difference is the driving force of the membrane that is created by temperature difference across the two sides of it. He, Hwang et al. (۲۰۱۱). He, Hwang et al. (۲۰۱۱).