SIMPLE, LOW MAINTENANCE ALGAE AMMONIA CONTROL IN AN AERATED POND SYSTEM

摘要

This paper presents a case study on upgrading an aerated pond system for algae andrnammonia control. Initially algae was to be controlled with the disinfection system, butrnthis proved difficult to operate. A study was conducted on coagulation and filtrationrnbut it turned out unsuccessful. Finally a modular, floating membrane cover was placedrnover the sedimentation and polishing ponds initially, later followed by the aeration pondrnand the algae decreased dramatically. By cutting out sunlight, algae was preventedrnfrom growing and the effluent suspended solids dropped below 10 mg/l.rnOnce the algae was under control, the residual ammonia concentrations could bernaddressed. Since the aeration pond could not build up biomass (no return fromrnsedimentation pond), racks of submerged media were installed in the aeration pond.rnThe media allowed a resident population of nitrifiers to develop and the bacteriarnquickly lowered the ammonia near 1.0 mg/l in the effluent.