Treatment of land ll leachate from a Swedish municipal waste land ll: The potential of biological nitrogen removal with sequencing batch reactor technology

This paper covers the start-up of a pilot-plant experiment where land ll leachate from a Swedish municipal waste land ll (Spillepeng) was treated using a sequencing batch reactor (SBR). The leachate was characterised by high COD and NH4-N concentrations, low BOD/COD ratio, pH slightly over 7 and a high conductivity. During the studied period the mean temperature was 21°C, pH was 7.5 in the reactor, the hydraulic retention time reached 1.7 days and the sludge age was kept long due to the start-up and problems with loss of sludge. The results show that the SBR-technique has a good potential in treating the leachate from the nitrogen fractions ammonium, nitrate and nitrite. The nitri cation was easy to start-up and the reduction of ammonium nitrogen was found to be 97 %. The denitri cation was harder to start due to technical problems but complete denitri cation was reached after 166 days.