Sounds Too Good To Be True – Only if You Don't Listen - Managing Co-Digestion of High Strength Waste

Utilities traditionally have used anaerobic digestion to treat the biosolids generated from wastewater treatment. However, in recent years this practice has expanded to include codigestion of fats, oils, and grease (FOG) and other food processing wastes (High Strength Wastes-HSW). Previously considered to be a nuisance, FOG is now beginning to be recognized for its benefits to the microbial fauna and for its biogas production potential. At the same time, various local and state governments are starting to regulate the amounts of oils and grease discharged into their sewer networks in order to avoid sanitary sewer overflows (SSOs).The acceptance of FOG as a co-digestion feedstock has put pressure on the supply of FOG and is encouraging POTWs to explore other HSWs for co-digestion. As with the early days of FOG digestion, feeding other HSWs to an anaerobic digester has many challenges and many rewards. A thorough and early evaluation of potential HSWs along with a flexible design provides a path to success in co-digestion of HSW.