Ultrasonic treatment of digested and waste activated sludge using an innovative flatbed reactor: Impact on COD solubilization and specific methane yield
Digested and waste activated sludge from a municipal wastewater treatment plant were treated with a novel flatbed ultrasonic reactor.At the highest specific energy input applied (~5,000 kJ/kgTS),a soluble chemical oxygen demand release of 105% and 766% was achieved for digested and waste activated sludge,respectively.Specific methane yields increased by 85% for digested and 23% for waste activated sludge.The novel flatbed reactor is less prone to clogging than conventional sonotrode reactors due to an unobstructed reaction chamber.In addition,the reactor was capable of treating substrates with a high solids content (4.9% solids content waste activated sludge) in contrast to tube reactors,which are subjected to strong sound wave attenuation due to profile geometry and a lower oscillation amplitude.Based on the results,a sampling campaign was carried out and sludge samples (primary,waste activated and digested sludge) from 10 wastewater treatment plants were collected and chemically analyzed.Sonication was conducted for additional samples to generally correlate sludge chemistry and sonication amenability.To further investigate the strong increase in methane yield for digested sludge,a continuously operated system was developed.The system was comprised of two identical 32 l reactors,which were inoculated with 30 l digested sludge.Both reactors were equipped with a recirculation loop (from which only one was sonicated) and an automated feeding system for waste activated sludge.Potential differences due to ultrasonic treatment were assessed by use of volumetric gas meters,a gas quality analyzer and chemical analyses of the treated and untreated sludges.
Ultrasonic flatbed reactor digested sludge waste activated sludge soluble chemical oxygen demand release specific methane yield
Thomas Lippert Jorg E.Drewes Konrad Koch
Chair of Urban Water Systems Engineering, Technical University of Munich, Am Coulombwall 3, 85748 Garching, Germany
国际会议
The 15th IWA World Conference on Anaerobic Digestion( 第15届IWA世界厌氧大会)
北京
英文
777-780
2017-10-17（万方平台首次上网日期，不代表论文的发表时间）