New Techniques for Recovering Exhaust Heat from Gas Turbines Applied to Water-Energy Nexus

To optimize efficiency and performance in power generation plants, it is essential to recover waste heat from exhaust gases. Traditionally, this heat has been devoted to fuel any thermal process along the system served by the power generator. However, when there is not enough thermal demand within the global process the efficiency cannot be improved. In this regard, this chapter aims to help this purpose by creating new thermal requirement linked with water recycling. Mathematical process modelling as well as thermal engineering are the tools to carry out the optimization of gas turbine exhausting recovery. Industrial processes where important amounts of water are required, can be improved from a water-energy consumption efficiency by including thermal distillation and condensation by absorption cycle within the current global process. As a main result, it is shown how to minimize either primary energy consumption or production costs. Besides, water consumption is reduced as much residual water is recycled, and CO2 emissions as combustion processes are cut down. Although energy consumption may be increased, the global water-energy combined resource results reduced. It can be concluded that resources consumptions are definitively optimized by integration of water-energy nexus and conveniently designed new thermal processes to match energy and water demand curves with production ones.