ANALYSIS OF FRESH WATER GENERATOR OPERATION ON BOARD LNG/C SS. EKAPUTRA 1

Abstract

Fresh water is an essential commodity on board vessels, particularly on LNG/C SS. Ekaputra 1, where it is used as feed water for the main boiler to support high-pressure steam production. The vessel is equipped with a Fresh Water Generator (FWG), an auxiliary device that converts seawater into fresh water through evaporation and condensation processes. Following observation and interviews with the engineer responsible for the equipment, a decline in fresh water production from the FWG was identified. The research findings revealed two principal causes of the production decrease: leakage of the cooling tube in the condenser and the accumulation of salt deposits on the mesh separator. The cooling tube leakage was attributed to operational errors during the startup procedure, specifically the excessively rapid opening interval of the steam inlet valve for the air ejector, which caused rapid pressure changes and thermal differentials that compromised the material integrity of the cooling tube, leading to cracking and leakage. The salt deposits on the mesh separator were caused by the mineral salt content in seawater; under vacuum conditions in the flash chamber, the boiling point decreases and the temperature rises, causing the water to evaporate while the salt remains and accumulates on the mesh separator. Consequently, repairs to the leaking cooling tube and chemical cleaning of the mesh separator are necessary to restore optimal FWG production capacity.