Ammonium uptake by zeolite and treatment in UASB reactor of piggery wastewater

A treatment plant of pre-screened piggery wastewater is tested at lab-scale using Italian zeolites (of very low cost) to strongly reduce the NH4+ from 1500 mg/l to 300-400 mg/l and anaerobic digestion in UASB and UASB-AF reactors to remove organics. The ion-exchange pre-treatment by zeolite leads to a reduction of toxicity of wastewater towards anaerobic microbial population and improves the UASB and UASB-AF reactors yields in organics reduction and gas production, The laboratory plant in this configuration reaches a COD removal range of 60-80% and a good reduction of effluent nutrients concentration whereas the use of a anaerobic second stage gave modest results in organics removal because of low applied organic load. A treatment cycle composed of a pre-treatment with zeolites, anaerobic digestion in UASB-AF reactor and a final treatment in an aerobic activated sludge plant is giving very good preliminary results.