The power station is a two (2) unit coal fired steam plant with each unit having a net electrical output of 610 MW. The power generation of the power station is based on the following major systems :
- Heat Generation
- Electricity Generation
- Condenser and Cooling Systems
- Exhaust Gas Treatment and Ash Handling
Coal delivered by ship is unloaded at a jetty and transferred by conveyor belts to the coal storage area. Coal is further supplied by conveyor belts into the coal bunkers (1) adjacent to the steam generator. Coal mills (2) grind the coal from the coal silos in order to reduce the coal particle size. The ground coal is then injected through the burners into the furnace where the burning coal generates the heat necessary for steam generation. Air is supplied by combustion air fans (5) via a flue gas air heater (4). The flue gas air heater transfers heat from the exhaust gas of the steam generator to the combustion air, improving the efficiency of the plant.
Steam enters the turbine through valves (11) which control the flow of steam. Within the turbine, high pressure steam expands stage by stage, building up flow of energy which is then transformed into mechanical energy. The steam turbine is divided into a high pressure module, an intermediate pressure module and two (2) low pressure modules to accommodate the wide range of steam conditions during expansion of the steam. In order to improve efficiency, exhaust steam from the high pressure module is routed again through the steam generator (3) and reheated before it enters the intermediate pressure module at a temperature of 538 °C and a pressure of 39 bar. The mechanical energy of the turbine is transformed in the generator (12) into electrical power. The electrical power is converted by the generator transformer (13) to the necessary voltage and supplied into the Java-Bali 500kV grid.
In order to provide a closed cycle, exhaust steam from the turbine is condensed in the condenser (14) and cooled by sea water from the Java Sea. The seawater is cleaned by the cooling water cleaning system (20) and circulated by cooling water pumps (21) through the condenser to the seal pit (22) before it is returned to the sea through the outlet culvert (23). The condensed steam then flows through some preheaters (16) and is conveyed by the feedwater pump (18) through further preheaters (16) to the steam generator.
Ash from the exhaust gas of the steam generator is filtered in electrostatic precipitators (6) and transferred together with ash from the furnace of the steam generator by ash handling equipment (10) to the ash disposal area. The Pulverised Fly Ash (PFA) is delivered to the ash disposal area by a pneumatic piping system while the Furnace Bottom Ash (FBA) is transported by skip lorries. Sulphur dioxide is removed from the exhaust gas in a flue gas desulphurisation plant (8). The exhaust gas is forwarded by the flue gas fan (7) and leaves the plant through a 220-m high stack (9).