Gas Fuel Mixing to Reduce Elemental Sulfur Formations on Gas Regulating and Metering Stations in Muara Karang Steam Power Plant

Abstract

Muara Karang Steam Power Plant uses natural gas as a primary energy source. Gas supplied from three different suppliers, PHE, PGN, and NR. Each supplier has different gas quality because it sourced from different gas fields and processes. To feeds gas to the boiler in Unit 4 Muara Karang Steam Power Plant, it has gas regulating facilities to reduce the pressure of natural gas from 24 kg/cm2 to 4 kg/cm2. In 2019, Control Reducing Valve (CRV) opening climbs gradually although power output from Unit 4 is constant. Inspection of the strainer found that elemental sulfur formations occur, and a clogged strainer makes gas flow to the burner reduced. To compensate for elemental sulfur formation, a fuel mixing strategy was implemented. Before the fuel mixing strategy implemented, Unit 4 needs maintenance outage every three months with a CRV gas opening increase of 0.93%/day. After the fuel mixing strategy implemented, it needs maintenance outage every five months and CRV gas opening increase of 0.44%/day because elemental sulfur formation occurs slower. The fuel mixing strategy can save up to 11.7 billion rupiahs of outage cost.