biosållar

Biosållar are a type of biological filter used in wastewater treatment. They are also known as trickling filters or percolating filters. The principle behind a biosåll is to provide a surface for microorganisms to grow on, which then consume the organic pollutants in the wastewater as it flows over them.

Biosållar typically consist of a bed of inert material, such as gravel, crushed stone, or plastic media, through which wastewater is passed. The large surface area of the media provides a suitable habitat for a biofilm to develop. This biofilm is a complex community of bacteria, fungi, protozoa, and other microorganisms. As wastewater trickles down through the filter, the organic matter in the water is adsorbed onto the biofilm, where it is then metabolized by the microorganisms.

The treated wastewater is collected at the bottom of the biosåll. The efficiency of a biosåll depends on several factors, including the type of media used, the loading rate of wastewater, the depth of the filter, and the temperature. Biosållar are effective at reducing biochemical oxygen demand (BOD) and suspended solids. They are a relatively simple and robust technology, often used in smaller wastewater treatment plants or as a secondary treatment stage after primary sedimentation. Variations of biosållar exist, including enclosed or aerobic variants, which can offer improved performance and control.