WAS Pretreatment to Boost Volatile Solids Reduction and Digester Gas Production – Market and Technology Assessment

Tightening regulations and reduced landfill and land application capacity have led to increasing cost of biosolids disposal. Multiple WAS pretreatment technologies have demonstrated the ability to reduce biosolids mass and enhance digester gas production. The effectiveness and cost savings for various WAS pretreatment technologies can be very site specific. This paper will provide a critical review of existing and developing technologies for WAS pretreatment and will provide a summary of data from laboratory, pilot, and full scale operations. A recent electrokinetic disintegration WAS pretreatment pilot study at a 20 mgd WWTP in the Southeastern USA indicated that this technology would be most appropriate for facilities with short anaerobic digester retention time.