摘要 |
<p>A process is described for the biological treatment of waste water containing ammonia, wherein the waste water is treated with sludge containing nitrifying bacteria in an aerated reactor, applying a sludge retention time in the reactor which favours nitrite-producing bacteria over nitrate-producing bacteria. The process is characterised by applying a hydraulic retention time in a continuously operated reactor, which is shorter than the sludge retention time as a result of part of the sludge being separated from the reactor effluent and being returned to the reactor. The performance of the nitrification is further improved by applying low oxygen and nitrite concentrations.</p> |