NaH_2PO_4as pH buffer in an anaerobic ammonium oxidation (anammox)reactor treating high-strength livestock manure digester liquor

摘要

In order to use livestock manure digester liquor (LMDL) as liquid fertilizer, NaH2PO4 was evaluated for its effectiveness as pH buffer in an anaerobic ammonium oxidation (anammox) reactor treating high-strength LMDL. The results show that influent total nitrogen (TN) concentration was increased from 500 to 2,200mg/L with the addition of NaH2PO4 as a pH buffer. To the best of our knowledge, this is the highest influent TN concentration for anammox reactor in treating LMDL. An average TN removal efficiency of 85% was observed in LMDL treatment without dilution. The treated effluent may be applied directly as a terrestrial liquid fertilizer, as the effluent has a suitable balance of nitrogen and phosphorus (approximately 1:1). 16SrRNA gene analysis showed that Kuenenia stuttgartiensis and Uncultured bacterium clone KIST-JJY001, known as anammox bacteria, shared approximately 26% in genus level in the reactor. Uncultured bacterium clone Dok53, Uncultured bacterium clone KIST-JJY024, Uncultured bacterium clone FN-11, Uncultured bacterium clone KIST-JJY012, and Uncultured bacterium clone AnSal-09, which are often detected as co-occurring bacteria, were also found in this study.