Future of Sewage Sludge Management and Phosphorus Recovery

Abstract

This article demonstrates how the currently discussed statutory requirements of the forthcoming sewage sludge ordinance can be implemented practically in wastewater treatment plants and/or within the scope of sewage sludge management. The application of processes for phosphorus recovery from sludge liquor will be insufficient to meet the statutory regulations due to the excessively high content of residual phosphorus in the sewage sludge. However, based on the currently achieved phosphorus reductions for average phosphorus contents in the sewage sludge, at least two processes for phosphorus recovery from sewage sludge allow for subsequent co-incineration. In all cases, the monoincineration of the sewage sludge, followed by the prompt phosphorus recovery or retrievable separate storage of the ashes will be compliant with the new requirements.