A novel scheme was developed for the treatment of municipal wastewater integrating nitritation/denitritation with the selection of polyhydroxyalkanoates (PHA) storing biomass under an aerobic/anoxic,feast/famine regime. The process took place in a sequencing batch reactor (SBR) and the subsequent PHA accumulation in a batch reactor. The carbon source added during the selection and accumulation steps consisted of fermentation liquid from the organic fraction of municipal solids waste (OFMSW FL) (Period I) and OFMSW and primary sludge fermentation liquid (Period II).
Selection of PHA storing biomass was successful and denitritation was driven by internally stored PHA during the famine phase. Under optimum conditions of SBR operation ammonia removal was 93%,