Onsite Treatment of Septic Tank Effluent: An Evaluation of Rotating BiologicalContactor Capabilities

摘要

A rotating biological contactor (RBC) was evaluated with respect to nitrogenremoval and practicality of use in tandem with a septic tank at a single family dwelling. The unit was used to treat wastewater generated by five persons and which was discharged into a 1500-gallon septic tank. Principal operational variables evaluated included hydraulic loading rate, disc rotational speed, anoxic stages, and varying recycle of effluent. Two modifications were made to promote nitrogen removal in the system; establishing anoxic conditions in the third stage, and making the first stage anoxic and recycling final effluent. Effluent was recycled at a ratio (recycle: influent) of 3:1, 2:1, 1:1, and zero.