Water and Wastewater Treatment

During wastewater treatment, sludge is processed and can be used as nutrient-rich manure or fertilizer due to its organic content and beneficial microorganisms. The sludge undergoes stabilization to reduce pathogens and is then safely applied to agricultural land as a soil amendment.

Water is removed from activated sludge using sand drying beds, where the sludge is spread and allowed to dry through evaporation and percolation. This method effectively reduces water content through natural processes. Skimmers remove floating materials, aerators add oxygen, and sand removal tanks are earlier in the treatment process.

Activated sludge typically contains about 97% water, with the remaining 3% being suspended solids and microorganisms. This high water content is characteristic of the biological flocculent material formed during the aeration stage of wastewater treatment.

Chlorine and ozone are both powerful disinfectants used in wastewater treatment to kill or inactivate harmful pathogens, bacteria, and viruses. Chlorine provides residual protection in the distribution system, while ozone is a stronger oxidant that leaves no harmful byproducts, making them effective for water disinfection.

Biogas is produced during treatment of waste water which is used as a source of energy.

Waste water after treated with skimmers in the treatment plant is called clarified water.

Potassium permanganate (KMnO4) is a powerful oxidizing agent that kills bacteria and other microorganisms in water through oxidation reactions. It oxidizes organic impurities and pathogens, making water safe for drinking. Options A and B are incorrect - it doesn't dissolve impurities or act as a sterilizing agent in the traditional sense.

Sewage treatment is the correct term for the process of removing contaminants from wastewater. Water management is too broad, water harvesting is about collecting rainwater, and water cleaning is not the technical term used in environmental engineering.

Contaminants is the correct term for dissolved and suspended impurities in water. Feces refers to solid waste (misspelled as 'Faces'), sludge is semi-solid byproduct of treatment, and biogas is a fuel gas produced from organic matter breakdown - none describe dissolved/suspended impurities.

Aeration, filtration, and chlorination are all treatment processes used to clean water - they are actions taken to improve water quality. Sludge is the semi-solid byproduct that remains after treatment, not a process itself. It's the odd one out because it's a substance rather than an action.

Aerator is used to add oxygen to polluted water.

Waste Water Treatment Plant

Chlorination is the process of adding chlorine or chlorine compounds to water for disinfection. Using chlorine tablets is a common method, especially for point-of-use treatment or in emergency situations. The chlorine kills harmful microorganisms, making water safe for drinking.

Bar screen removes rags, cans, plastics packets from the waste water

Grit remove solid waste like faeces from waste water