Aquadest Production with Compression System: Influence Cyclone Separator Pressure and Percentage of Water Discharged on Specific Energy Consumption

Abstract

The ease of people in obtaining clean water is still a problem in Indonesia. The reason is that there are still more than 25% of the people who have not been able to use clean water to meet their daily needs. Indonesia was in the spotlight because it was considered as one of the countries that became the most significant contributor to water pollution, especially through plastic waste. The need for clean and safe water is growing as the population growth as well. Seawater desalination has become one of the essential commercial processes for providing clean water to many communities and industrial sectors that play an important role in socio-economic development in several developing countries, especially in Africa and several countries in the Middle East. The region, which suffers from the scarcity of fresh water. This paper aims to simulate the processing of seawater into clean water ready for use. The source of heat that is use comes from the cooling water condenser of steam turbine power plants. The method to be used is a thermodynamic simulation by using temperature in the cyclone separator and the percentage of water discharged into the sea variation to find out the amount of aquadest production and the Specific Energy Consumption (SEC) in the system. The lower temperature in a cyclone separator, the more aquadest production. The more mass water discharged to the sea, the less SEC will obtain. The minimum SEC is -1137.62 kJ/kg aquadest for 0.86 kg/s aquadest at 99% of mass water discharge and 2.645 kPa pressure in the cyclone separator and then the higher SEC is 440.53 kJ/kg aquadest for 0.338 kg/s at 89% of mass water discharge and 0.706 kPa pressure in the cyclone separator. The effect of lowering the condenser pressure is to increase the power of steam turbine 1181.85 kW, and then the cooling water temperature of the condenser decrease from 37.5°C to 32.5°C. The cooling water of condenser will be discharged partially into the sea at 32.5°C, which is safe for the environment.