C, 45 bar, which is fed to a steam turbine coupled to an electricity generator. The turbine generator is connected to the facility?s distribution system and in turn is inter-connected with Belco to enable energy to be either imported from, or exported to, the public supply system.

Each stream of the plant has a capacity to produce in excess of 2.5 megawatts (MW) of electricity, approaching five per cent of the Island?s average need.

After driving the turbine, the stream is condensed by sea water and passed back into the boiler system via a de-aerator to ensure water is returned to the boiler free of gases. If the turbine is shut down, the combustion process will continue by diverting the stream from the boiler to separate dump condensers.

The sea water used for condensing the steam is drawn through the pumping station located on North Shore Road. Band screens, located in the forebay of the pumping station, prevent coarse and particles, seaweed and other sea life from entering the pipes.

The sea water is returned to the ocean at approximately 100 C above ambient. This warmed water is dispersed into eight metre depth of water via a 350 metre outfall through a diffuser angled at 10 degrees to the seabed.

Combustion gases are cleaned by passing through electrostatic precipitators which remove in excess of 99 per cent of particulate matter in excess. From there, fans emit the gases to atmosphere through chimney flues at a height of 91 metre above sea level, 75 metre above the surrounding ground level, a height which ensures good dispersion.

Monitoring equipment continuously measures temperature, oxygen, carbon monoxide, sulphur dioxide, hydrogen chloride and opacity to establish that emissions remain within permitted limits.

Waste water generated at the facility is collected in a general purpose sump, a large storage tank under the eastern portion of the boiler house floor. From there it is pumped into the quench tank to be absorbed by the hot ash.

Ash that drops off the furnace grate (bottom ash) and the particulates removed by the electrostatic precipitators (fly ash) is also transported to the quench tank. The combined wet ash is then conveyed to the ash bunker for storage.

Ash handling equipment sited alongside the ash bunker is used to process the ash. The ash is graded by passing it over a 100mm screen, and ferrous material is removed with a magnetic separator. The ash is weighed and the moisture content determined prior to mixing with cement to form ash concrete to a strength of approximately 10N/mm2.

This ash concrete is formed into one metre cube blocks, each weighing approximately two tonnes, which are used for shore protection and land reclamation at the Airport Waste Management Facility.