Blacktown Water Treatment Plant Project Brief - 1230 Words

Blacktown Water Treatment Plant Project Brief Version: 1.1 Date: 8/22/2014 Copy: Uncontrolled Document Acceptance and Release Notice This is Version 1.1 of the Blacktown Water Treatment Plant Project Brief. Title: Blacktown Water Treatment Plant. Background: This treatment plant is designed to remove potentially harmful substances from waste water. It also includes safe effluent discharge and production of agro-ash. This is the process diagram of the treatment plant: [pic] Process flow - step 1 Preliminary treatment bar screen Removal of large objects As wastewater enters†¦show more content†¦The filters consist of finely crushed coal, about one meter in depth, and sand, half a meter in depth. This provides the final step in the treatment process. Process flow - step 6 Chlorination/dechlorination Chlorine is added to the effluent to disinfect any remaining microbiological pathogens; this takes at least half an hour. The effluent is then treated with sulphur dioxide gas to remove excess chlorine, which would be harmful to the river ecosystem. The effluent is then ready for discharge into the river. Process flow - step 7 Solids separation and incineration The sludge and scum, removed in step 2 of the process, are dealt with separately. The sludge is stored in a sludge holding tank where it is then pumped to the centrifuge at a controlled rate. Polymers are added to the sludge to aid in the thickening of the sludge during this process. Water is separated from the sludge by spinning in a centrifuge to form a thick, muddy substance known as cake, a process known as dewatering. The cake is then conveyed to the furnace where it is incinerated at 750-1000 °C to produce Agri-Ash. The scum, however, is stored in a heated tank to thicken it prior to its transfer to the furnace, where it is also incinerated. Approximately 700,000 litres of sludge is treated each day to produce 47 tonnes of dewatered solids. After