Legislation for using sewerage sludge in agriculture defines 2 types of sludge product; treated and enhanced treated. Enhanced treated sludge is pasteurised / disinfected and is used by farmers without cropping restrictions.
If existing assets can be used to cost effectively produce enhanced treated sludge, this will give flexibility for future sludge disposal options to cope with public / stakeholder perception and potential legislation changes. These disposal options include continued use in agriculture and complying with legislation such as increased treatment to catering waste before recycling.
The objectives of this work were therefore to determine whether existing anaerobic digesters could operate at 55oC and produce enhanced treated sludge.
Benefits to Clients
- Identification of whether major assets (existing anaerobic digesters) can be adapted to meet changing needs during uncertainty in regulation and public / stakeholder perceptions
- Knowledge that existing digesters can be converted to operate at higher temperatures when required may delay major capital expenditure
- Optimising efficiency of treating sludges with a high proportion of secondary solids.