NUTRIENT REMOVAL FROM INDUSTRIAL WASTE-WATER USING SINGLE TANK SEQUENCING BATCH REACTORS

Biological Nutrient Removal (BNR) has been developed in recent years t o achieve high quality effluent in regards to carbon, nitrogen and pho sphorus compounds. However, most of these results have been achieved o n domestic sewage. In treating industrial wastewater, additional chall enges are facing the process designer and operator due to the substant ially higher concentrations of both carbon and nutrients. This researc h and demonstration project is addressing the issue for abattoir (slau ghterhouse) effluent. The technology used should be as simple as possi ble yet still achieve a high degree of BNR. The process used in labora tory and pilot scale isa single tank Sequencing Batch Reactor (SBR). T he results from the laboratory work have been excellent but have to he confirmed in the pilot plant studies. It was found that a certain deg ree of anaerobic pretreatment (e.g. in anaerobic ponds) can reduce par t of the carbon concentration most efficiently while still leaving suf ficient COD required for successful BNR. Despite high influent concent rations of approximately 190 mg L-1 N and 50 mg L-1 total P, good effl uent quality of less than 20 mg L-1 N and less than 5 mg L-1 total P h as been achieved. Furthermore the operation of the small SBR systems h as proved to be simple and reliable. (C) 1997 IAWQ. Published by Elsev ier Science Ltd.