At a wastewater treatment plant, grease and sand is removed by means of a trap to protect the plant equipment from damage in the following treatment processes. There are various ways of cleaning wastewater, but the far most common is a combination of mechanical and biological treatment. Wastewater is here cleaned in steps, with a biological process or aeration of the wastewater in order to carry out nitrification and denitrification processes.
Mechanical wastewater treatment is used to remove any solid matter, and involves the processes of filtration (or separation) and sedimentation. In the biological stage, the impurities which are not picked up by the mechanical process, are treated. This takes place in a sludge activation tank. Other processes (e.g. trickling filter, immersion filter) are used in isolated cases.
Sludge is produced as a waste product of the treatment processes. Treatment and preparation of sludge gives rise to its own equipment requirements, which may vary significantly depending on the specific plant. The most common way of disposing sludge is still through use in agriculture, but can too be delivered to an external biogas plant and used in renewable energy production.
AVK offers a wide selection of gate valves, butterfly valves, check valves, slide- and knife gate valves, air valves, surface boxes, couplings, adaptors, repair clamps, tapping saddles, and valve accessories for projects within wastewater treatment.