Katsou E., Malamis S., Frison N., Fatone F., 2014, Effect of Nitrite and External Carbon Source on the Via Nitrite Biological Phosphorus Removal, Chemical Engineering Transactions, 38, 25-30.
The via nitrite biological phosphorus removal was investigated in batch experiments using biomass collected from a sequencing batch reactor (SBR) treating low strength nitrogenous effluents. The effect of the initial nitrite concentration and the external carbon source characteristics on the via nitrite specific phosphorus uptake rate (sPUR) was investigated. The external carbon sources that were applied consisted of fermented liquid produced from the organic fraction of municipal solid waste (OFMSW FL), fermented liquid produced from vegetable and fruit waste (VFW FL) and VFW enriched with propionic acid and/or butyric acid. The type and composition of the applied external carbon source critically impacted the via nitrite sPUR. The addition of OFMSW FL resulted in very high via nitrite sPUR (7.25 mgP/(gVSS·h)) and specific phosphorus release rates (sPRR=5.11 mgP/(gVSS·h)). The presence of propionic acid and butyric acid in OFMSW FL promoted phosphorus uptake. The short chain fatty acids (SCFAs) in the VFW FL consisted mainly of acetic acid and resulted in lower sPUR. Furthermore, increased concentration of SCFAs in the mixed liquor enhanced the via nitrite phosphorus removal. The presence of nitrite in the mixed liquor did not adversely impact the phosphorus uptake mechanism up to the concentration range of 50-70 mg/L. However, higher nitrite levels (100-120 mg/L) resulted in some sPUR inhibition.
