Wastewater Treatment
ACTIVATED SLUDGE DIAGRAM
DEFINITION:
Activated sludge is a term that refers to suspended aerobic consisting of flocs of active bacteria, which are mixed with wastewater. The bacteria consume and remove aerobically biodegradable organic substances from screened; or screened and presettled wastewater in an aerated tank. The organic pollutants in the wastewater are used by the bacteria to grow and transform it to energy, water, CO2 and new cell material.
Activated sludge systems are suspended-growth type and are used in conventional high-tech wastewater treatment plants to treat almost every wastewater influent such as , brownwater, greywater, faecal sludge and industrial wastewater as long as it is biodegradable.
PART 1: WASTEWATER TREATMENT
1. PRELIMINERY TREATMENT (Primary & Secondary Filtration)
Pump station:
Water from public channel network and storm water basin enters the inlet chamber.
Bar Screen:
Screening - removing particles such as plastics paper, cloths, and other large debris that may damage mechanical equipments.
Screened solids are landfilled or incenerated.
Grit Chamber:
Aeration – removing sand and other heavy particles from other suspended solids within a short period of time.
Aerated sand are landfilled or incenerated.
2. PRIMARY TREATMENT (Primary Clarifier)
Primary Sedimentation Tank:
Settling - Waste water spends a number of hours to allow the finer solids to settle or float and the sludge produced is scraped along the base of the tank for desludging. The primary-treated waste water is passed to an aeration tank.
3. SECONDARY TREATMENT (Aeration & Sceondary Clarifier)
Aeration Tank:
Aeration provides oxygen to the activated sludge and at the same time thoroughly mixes the sludge and the wastewater. Aeration is by either bubbling air through diffusers at the bottom of the aeration tank, or by mechanically agitating the surface of the water. After the aeration stage the waste water enters a second sedimentation tank.
DEFINITION:
Activated sludge is a term that refers to suspended aerobic consisting of flocs of active bacteria, which are mixed with wastewater. The bacteria consume and remove aerobically biodegradable organic substances from screened; or screened and presettled wastewater in an aerated tank. The organic pollutants in the wastewater are used by the bacteria to grow and transform it to energy, water, CO2 and new cell material.
Activated sludge systems are suspended-growth type and are used in conventional high-tech wastewater treatment plants to treat almost every wastewater influent such as , brownwater, greywater, faecal sludge and industrial wastewater as long as it is biodegradable.
PART 1: WASTEWATER TREATMENT
1. PRELIMINERY TREATMENT (Primary & Secondary Filtration)
Pump station:
Water from public channel network and storm water basin enters the inlet chamber.
Bar Screen:
Screening - removing particles such as plastics paper, cloths, and other large debris that may damage mechanical equipments.
Screened solids are landfilled or incenerated.
Grit Chamber:
Aeration – removing sand and other heavy particles from other suspended solids within a short period of time.
Aerated sand are landfilled or incenerated.
2. PRIMARY TREATMENT (Primary Clarifier)
Primary Sedimentation Tank:
Settling - Waste water spends a number of hours to allow the finer solids to settle or float and the sludge produced is scraped along the base of the tank for desludging. The primary-treated waste water is passed to an aeration tank.
3. SECONDARY TREATMENT (Aeration & Sceondary Clarifier)
Aeration Tank:
Aeration provides oxygen to the activated sludge and at the same time thoroughly mixes the sludge and the wastewater. Aeration is by either bubbling air through diffusers at the bottom of the aeration tank, or by mechanically agitating the surface of the water. After the aeration stage the waste water enters a second sedimentation tank.
References: United Nations Environment Programme. Activated Sludge Treatment. (International Source Book on Environmentally Sound Technologies for Wastewater and Stormwater Management). 4.2.1 (online). Retrieved from http://www.unep.or.jp/ietc/publications/techpublications/techpub-15/2-4/4-2-1.asp Sustainable Sanitation and Water Management. Activated Sludge (online). Retrieved from http://www.sswm.info/category/implementation-tools/wastewater-treatment/hardware/semi-centralised-wastewater-treatments-7 The Scottish Government. Wastewater Treatment Process Overview. (Code of Practice on Assessment of Odour Nuisance from Waste Water Treatment Works). Part 1 (online). Retrieved from http://www.scotland.gov.uk/Publications/2005/04/2994932/49358 Luis H. Abreu & E. Saribel. Sequencing Batch Reactors: An Efficient Alternative to Wastewater Treatment (online). Retrieved from http://www.rpi.edu/dept/chem-eng/Biotech-Environ/Environmental/Steps/EnvSysSBR.html#anoxic Wastewater Engineering Group. SBR – Sequencing Batch Reactor Systems from Wastewater Treatment (online). Retrieved from http://wastewaterengineering.com/sbr_sequencing_batch_reactors.htm R. Hamzah & P. M. Victor. (2008). Design and Performance of Waste Stabilization Ponds (online). Retrieved from http://stabilizationponds.sdsu.edu/ The Wastewater Treatments. Waste Stabilization Ponds (online). Retrieved from http://www.thewatertreatments.com/wastewater-sewage-treatment/waste-stabilization-ponds-waste-water-treatment http://www.rdn.bc.ca/cms/wpimages/wpID1165imgID1094.jpg