Exploratory study of municipal wastewater primary sedimentation basin effluent treatment using an upflow anaerobic filter

Abstract

This report describes the results of exploratory tests conducted using a 95-liter upflow anaerobic filter (UAF) bioreactor test unit fed raw primary sedimentation basin effluent at a municipal wastewater treatment plant. The main objectives of the exploratory study were to obtain substrate conversion and hydraulic data for use in making full-scale projections, evaluate potential biofilm support materials, and to assess the suitability of the upflow anaerobic filter unit process as part of a new concept for a complete municipal wastewater treatment plant. The tests were conducted using available equipment with no effort made to optimize the system. The main findings of the tests are: COD loading rate: 2,1 kg COD/m3/day, hydraulic retention time: 3 hours, average influent energy conversion: 71% (Influent HHV -effluent HHV), biogas CH4 content up to 65%, stable operation at 16°C, evaluation of different biofilm support materials (see text), non-biodegradable ash and phenolic compounds account for at least 63% of the total solids contained in primary sedimentation basin effluent and they are the most important contributors to turbidity.