The SHARON((R))-Anammox((R)) process for treatment of ammonium rich wastewater

The treatment of ammonium rich wastewater, like sludge digester effluent, c an be significantly improved when new biotechnological processes are introd uced. In this paper, the combination of a partial nitrification process (SH ARON (R)) and anoxic ammonium oxidation (Anammox (R)) process for the treat ment of ammonia rich influents is evaluated. Herein the combined process ha s been studied with sludge recycle liquor from the WWTP Rotterdam-Dokhaven. The SHARON process was:operated stably for more than 2 years in a 10 l CST R under continuous aeration with a HRT of 1 day. The ammonia in the sludge liquor was converted by 53% to nitrite only. During the test period no form ation of nitrate was observed. The effluent of the SHARON process was ideal ly suited as influent for the Anammox reactor. The Anammox process was oper ated as a granular sludge SBR-process. More than 80% of the ammonia was con verted into dinitrogen gas at a load of 1.2 kgN/m(3) per day. Planctomycete -like bacteria dominated the mixed community of the Anammox reactor, and on ly a small percentage of the population consisted of aerobic ammonium-oxidi zing bacteria. This showed that the ammonium-oxidizers in the effluent of t he SHARON process did not accumulate in the SBR. The test period showed tha t the combined SHARON-Anammox system can work stably over long periods and the process is ready for full-scale implementation.