In primary treatment, sewage is stored in a basin where solids (sludge) can settle to the bottom and oil and lighter substances can rise to the top. These layers are then removed and then the remaining liquid can be sent to secondary treatment. Sewage sludge is treated in a separate process called sludge digestion.Jan 3, 2021,
There are three main stages of the wastewater treatment process, aptly known as primary, secondary and tertiary water treatment.Dec 6, 2018
Secondary treatment is the removal of biodegradable organic matter (in solution or suspension) from sewage or similar kinds of wastewater. The aim is to achieve a certain degree of effluent quality in a sewage treatment plant suitable for the intended disposal or reuse option.
Sewage Treatment refers to the process of removing contaminants, micro-organisms and other types of pollutants from wastewater. Wastewater, or raw sewage, is water that drains from toilets, sinks, showers, baths, dishwashers, washing machines and liquid industrial waste.
Primary Treatment: This step involves the removal of physical particles from the sewage by filtration and sedimentation. First, all the floating debris is removed by filtration which is followed by the sedimentation where all the soil, stone and pebble are removed.
In the primary stage, solids are allowed to settle and removed from wastewater. The secondary stage uses biological processes to further purify wastewater. Sometimes, these stages are combined into one operation.