Mededelingen van de Vakgroep Gezondheidstechniek en Waterbeheersing (Treatment of Municipal Wastewater in a Pilot-Scale Airlift-Loop Reactor)

摘要

Recently, the airlift-loop reactor has been developed as a new type of bioreactor in which a high conversion efficiency can be obtained. The report presents the results of experiments on pilot-scale treatment of municipal wastewater. The biomass concentration in the reactor was 6-15 kg/cu m (volatile solids) at a COD loading rate of 8-14 kg/cu m.d, while the COD concentration in the presettled wastewater was 312-986 g/cu m. The sludge production (volatile solids) of the airlift-loop reactor was about 0.24-0.53 kg VS/(kg COD removed) at a sludge loading rate of 0.6-1.8 kgCOD/kgVS.d. From the aeration rate and COD removal an oxygen utilization efficiency of 16-34% could be calculated. The airlift-loop reactor is considered to be a promising process for treating municipal wastewater. However, further studies have to be done to improve the effluent quality and to gain more information about the possibilities of nitrification and nitrogen removal and about phosphate removal.