Aquadest production system as steam turbine bottom cycle II: Influence of condenser pressure and pinch point temperature difference

Abstract

Most of the energy derived from Steam turbine is discharge in the condenser at temperatures that may damage the environment. The condenser cooling water has gone through water treatment process, so it would be better used as raw material to produce aquadest. This study simulate a system that produces aquadest by throttling 10% of cooling water that coming out the condenser into a vacuum chamber (3 kPa). The resulting cold vapoor is condensed in the evaporator become aquadest. Cold water coming out the vacuum chamber is mixed with water coming out the condenser is lower than before. Parameters that varied are the condenser pressure and pinch point temperature difference (PPTD) inside the condenser. The simulation resulted the condenser cooling water temperature of less than 40 °C (design point), especially at PPTD of 9 °C. that applicable to all variations of condenser pressure 7 to 12 [kPa]. Spesific energy consumption of aquadest are between 550,7 to 900,3 [kPa] (less than half of water evaporation heat) and the aquadest flowrate are between 0,116 to 0,319 [kg/s].