A New Approach to Nutrient Removal Using the HYBACS Process

A major challenge facing the wastewater industry is the production of high quality treated effluents containing reduced concentrations of nutrients. The challenge relates equally to upgrading existing plants as to entirely new construction. The HYBACS process is a new approach to nutrient removal that has been developed from a process originating from South Korea called the RABC process. The process comprises two biological stages followed by clarification (or separation). The first stage comprises SMART units, and the second stage comprises activated sludge tanks. SMART units are a type of rotating biological contactor but the plates, 50 mm thick, are manufactured from mesh with a void of 95%, producing a biological environment containing aerobic, anoxic and anaerobic regions. The following describes the treatment system and the performance results obtained from two pilot demonstration plants installed in the UK and Spain. The plants have demonstrated that they can produce effluents with qualities compliant with the most stringent European nutrient removal standards, albeit supplementary chemical dosing may be needed to obtain compliance with the TP standards.