Boiler House A
SUMMARY
The four boilers of Station A were fired up in January 1951, each one being a 125/150,000lb per hour coal-fired boiler which was designed and constructed by International Combustion Ltd in London and Derby.
The rectangular structure of the boiler house faces a north-to-south direction, opposite the coal stack. Its steel frame structure extends to an approximate height of 25m with reinforced concrete external walls rendered with paint finish. A strong system of columns and beams highlight the nature of the building's structural frame with three external facades encompassing a number of openings of different sizes.
Combustion gases were released through two chimneys on the roof of the Boiler House, with the dust being cleaned by four electro static precipitators that were also located on the roof. The flat concrete roof has eight square holes from when the precipitators, chimneys as well as all plant and equipment were removed.
The east elevation is an approximate 120m in length with 24 repetitive bays of five metres each. The arrangement of each bay are divided into three windows of equal width but varies in height and position between the horizontal beams. Windows consist of a steel frame with glazing bars, although much of the glazing panes have since been broken or destroyed.
The internal structural steel frames are visible with a mezzanine walkway, consisting of concrete with a ceramic tile finish, running the length of the building.
THE COAL PROCESS
All eight boilers are equipped with an individual bunker (coal bin) for a supply of coal to enter and are weighed at this time to continually monitor the amount of coal being used by each boiler.
The coal then continues on to a pulveriser, all whilst maintaining a constant stream, where the coal will be grinded into fire dust.
It is then blown into the boiler's heated air, burning in a steady sheet of flames.
At the top of the room generators powered by large fans, blow the air for the combustion to take place. Not only does it keep the generating room cooler but it is also cleaner than if it the air was drawn in from outside.
Feedwater heaters (above photo) pre-heats the water that is delivered to a boiler for steam generation, making it more thermal efficient. Delivering cold water to the boilers could risk breaking the boiler or connecting plant equipment, due to the sudden variations of temperature.
The hot gases produced by the combustion of coal, passes over the boiler tubes containing water, boiling them in the process to create steam.
Each boiler at the power station could evaporate up to 22,679kgs of water per hour if needed (interestingly, the volume appears to be calculated as a weight mass rather than that of a liquid measurement).
Before the water could be used in the process, it required chemical treatment to prevent impurities from leaving deposits in the boiler tubes. This prevented a decrease in efficiency, which would have resulted from the serious damage that would have been caused without such treatment.
At the time of installing the chemical treatment plant, it was a first for Australian power stations and was proven to be so efficient and successful, similar plants followed suit, installing similar chemical treatment plants in lieu of previous and less efficient evaporative types of water purifiers.
Treated water tanks on the west side
Concrete blocks remain from the treated water tanks