New insight into the occurrence of volatile fatty acids in anaerobic sludge digesters at wastewater treatment plants in Denmark
Volatile Fatty Acids (VFAs) are important intermediates in the anaerobic transformation of organic wastes to methane.Their composition and concentrations are key parameters for process control and monitoring.In order to study the typical levels of VFAs in digesters at Wastewater Treatment Plants (WWTPs),common C1-C6 acids were analysed in 35 full-scale mesophilic and thermophilic sludge digesters located at 20 Danish WWTPs and 18 lab-scale reactors run with sludge from full-scale digesters.The results showed that,acetate,formate,and lactate were the most abundant acids in nearly all digesters.Total acids concentration was mostly lower than 2 mM and acetate lower than 1 mM,indicating good performance.Acetate as low as 0.1 mM was observed stably in several mesophilic digesters over months and it is much lower than that previously reported.These levels were verified in short-term lab-scale studies.In some digesters,formate was the most abundant VFA instead of acetate.Ion chromatography was applied for the analyses of organic acids.The results were also compared to a photometric method that is widely used at the WWTPs.The photometric method seriously overestimated the concentrations of total organic acids in most digesters,as the concentration in general was below the recommended analytical range,and interfering materials in the liquid phase of digesters were giving artificial signals.This photometric method is therefore not suitable for measuring VFAs in anaerobic sludge digesters from WWTPs even though widely used.
Volatile fatty acids anaerobic digesters ion chromatography photometric method surplus sludge wastewater treatment plant
Liping Hao Giulia Dottorini Martin Hjorth Andersen Morten Simonsen Dueholm Per Halkj(ae)r Nielsen
Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
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
755-758
2017-10-17（万方平台首次上网日期，不代表论文的发表时间）