Wastewater treatment

Following the initial filtering, the cleaning process beings. The most common process for wastewater treatment is a combination of biological and mechanical treatment. 

First, mechanical wastewater treatment is used to separate solids from liquid. It usually involves two steps, separation or filtration and sedimentation. Separation is carried out through various stages using different kinds of equipment and processes. Separation can remove coarse impurities such leaves, paper etc. using a rake or rotary screen. Following the separation, the sedimentation takes place in the sedimentation tank, where a purification (i.e., reduction of organic material) takes place.

Secondly, in the biological wastewater treatment process, impurities in the water not picked up by the mechanical process are treated. This is done by leading the wastewater is lead to a sludge activation tank where different processes such as filtration though immersion filter or trickling filters are used. 

The wastewater treatment process creates a biproduct called sludge, which gives rise to its own equipment requirements for handling. Sludge is usually disposed of by using it in agriculture but can also be used in biogas plants. 

For wastewater treatment, AVK offers various butterfly valves, specialized gate valves, check valves, knife gate valves, penstocks, weir gates air valves as well as various accessories such as couplings, adaptors, repair clamps, and fittings.