PENINGKATAN CONDENSER VACUUM DENGAN METODE HELIUM GAS TRACER TEST (HG2T) PADA AREA MEZZANIN UNTUK OPTIMASI PRODUKSI LISTRIK PEMBANGKIT DI PLTU PELABUHAN RATU

The condenser functions to condense exhaust steam from the LP Turbine and plays an important role in the Closed Cycle of the PLTU thermal cycle. The PLTU Pelabuhan Ratu uses a Steam Surface Shell & Tube Condenser type. The model of the condenser itself is Single Pressure, Two path. In operation, the condenser pressure is much lower than the pressure in the outside air. The condenser is designed to be vacuum so that exhaust steam from the LP Turbine can be perfectly condensed to the Hotwell and recirculated back to the Boiler. Vacuum condenser or commonly called Condenser Back Pressure, is one of the important parameters in PLTU operation. Condenser Back Pressure occurs due to the process of condensing steam into water, where there is a change in density from tenuous to tighter. To help maintain the vacuum value, a Vacuum Pump is used in each unit to keep the vacuum value within normal operating limits. One of the problems that is often encountered in condenser operation is increasing the Condenser Back Pressure value. Several factors affect the Condenser Back Pressure value, including Circulating Cooling Water quantity, Air in-leakage/Ingress, Vacuum Pump performance, Gland Seal Steam pressure, Excessive Drain Temperature & flow. One of the most common cases is high Air Ingress which causes an increase in the Condenser Back Pressure value. Two methods can be used to detect air ingress, namely the Online Test and the Offline Test. Online Test is a test when the unit is operating normally with the Helium Gas Tracer Test method which uses Helium or SF6 gas. The research results from online testing with this method have a high degree of accuracy because it is carried out when the unit is normally operating and is more measurable so that the level of leakage can be found in the gas detector.

Keywords: Air Ingress, Back Pressure, Condenser, Gas Tracer Test, Vacuum.