WEF Discussion Forums
Biosolids and Residuals
Low-cost low-tech approach to Class A Biosolids
I've recently taken an interest in low-cost/low-tech processes that use non-proprietary Sludge Process Trains (SPT) that are capable of producing a PFRP product that has been recognized by several State Biosolids Coordinators and the USEPA as Class A.
Although varied somewhat, each of the SPTs I’m interested in use a batch approach and age either an aerobically or anaerobically digested sludge in either a lagoon or in the case of a cake, separate piles. Once sufficiently aged, (generally about two years) the sludge is then spread onto a paved surface where it is windrowed and periodically agitated until it reaches a TS of ~65%.
I’ve now read several papers (available upon request) on this SPT and would like to invite further discussion on the process.