The anaerobic filter for waste treatment.

TLDR

The anaerobic filter is a rock‑filled bed resembling an aerobic trickling filter, historically used for high‑strength wastes, but conventional processes require long detention times and are uneconomical for low‑strength soluble organic wastes. Waste is distributed at the bottom of the submerged rock bed, where upward flow carries it through void spaces colonized by anaerobic microorganisms that contact the waste with a large active biological mass. The process achieves high treatment efficiency for low‑strength soluble organic wastes even at nominal temperatures, producing effluent essentially free of biological solids.

Abstract

An entirely new treatment process has been found to be particu larly effective for the treatment of low strength soluble organic wastes. This process, termed the anaerobic filter, is basically a rock-filled bed similar in appearance to an aerobic trickling fil ter. However, the waste is distributed across the bottom of the fil ter. Flow is upward through the bed of rocks so that the filter is submerged completely. Anaerobic microorgan isms accumulate in the void spaces be tween the rocks so that the waste comes in contact with a large active biological mass as it passes through the filter. A high degree of treatment re sults even at nominal waste tempera tures, and the effluent essentially is free of biological solids. Historically, systems have been used to stabilize high strength wastes, primarily composed of the solids produced by aerobic processes and removed from settling tanks. Con ventional processes have re quired long detention times for good waste stabilization and usually have been uneconomical for the treatment of waste containing less than approxi