| 摘要 |
A process for treating sewage sludge comprises the steps of: drying the sewage to a desired dry solids content and subsequently adding an alkali (eg lime) to pasteurise and/or stabilise the sludge. Optionally the sludge may be dewatered for example by belt press before being dried. The process may be continuous. Drying may be effected in single pass thin film driers and pasteurisation in a first-in-first-out hopper. Waste gases produced during pasteurisation are drawn off and subjected to biological or chemical scrubbing. Waste heat from the driers may be used to heat the scrubber apparatus or recovered to heat or provide hot water to the plant. |
