Nutrient recycles and other side effects of co-digestion of organic waste

摘要

This study evaluated operational side effects associated with co-digestion of high-strength waste (HSW) and conventional wastewater solids (thickened primary sludge and thickened waste activated sludge) at water resource recovery facilities (WRRFs). HSW co-digestion provides an opportunity to increase energy recovery through additional methane production with anaerobic stabilization. However, HSW co-digestion also presents several challenges to WRRF operations and maintenance staff. This goals of this study were two-fold. The first goal was to evaluate co-digestion facility design, performance data, and operation and maintenance issues at five WRRFs located in New York, Texas, and California. Several of these case-study WRRFs receive acid whey from Greek yoghurt production. The second goal was to conduct laboratory-scale biomethane potential (BMP) tests on conventional wastewater solids and HSW for three of these WRRFs, plus a fourth facility in Oregon, to evaluate the impacts of co-digestion of HSW on methane production, sludge production, and nitrogen and phosphorus concentrations in recycle streams.