Acclimation to extremely high ammonia levels during continuous biomethanation process
Anaerobic digestion (AD) is an effective technology to recover energy (CH4) from biomass.However,when protein-rich by-products are used as feedstocks,they could lead to low methane yields and even to complete process failure.Acclimatized anaerobic communities to high ammonia levels can offer a solution to this problem.Nevertheless,the acclimation to high ammonia levels during continuous AD of protein-rich substrates still poses serious challenges (e.g.microbes can be washed oat from reactors).In the present study,acclimation strategy followed by a stepwise increase (0.5 g NH4+-N L-1 each step) of total ammonia (TAN) concentration from 3.8 up to 10.5 g NH4+-N L-1 was investigated using continuous stirred tank reactors (CSTR) under mesophilic conditions (37±1℃).Microalgae Chlorella vulgaris (>50% protein in dry matter),mixed with cattle manure,was used as substrate.Throughout the acclimation period,even though the TAN increased 1.8-fold at the end of the experiment,the methane yield of the CSTR reactor was stable with an average variation less than 10% compared to the yield before ammonia acclimation started.At the same time,VFA and pH were both within the optimal range of AD process throughout the whole experimental period.These results demonstrated that an acclimation of ammonia tolerant methanogenic consortia to extreme ammonia levels using CSTR reactors is possible.Furthermore,microbiological analyses (16s rRNA sequencing) results confirmed a profound decrease in the microbial diversity due to the acclimation process.
Ammonia inhibition anaerobic digestion CSTR reactor methane microalgae
H.Tian I.A.Fotidis E.Mancini L.Treu A.Mahdy M.Ballesteros C.González-Fernández I.Angelidaki
Department of Environmental Engineering, Technical University of Denmark, Bygningstorvet Bygning 115 Department of Agricultural Microbiology, Faculty of Agriculture, Zagazig University, 44511 Zagazig, Biotechnological Processes for Energy Production Unit-IMDEA Energy, 28935 Móstoles, Madrid, ES
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
103-106
2017-10-17（万方平台首次上网日期，不代表论文的发表时间）