摘要
采用序批式厌氧发酵试验装置,研究了温度对生猪养殖废水厌氧发酵产酸初期影响。利用16rsDNA高通量测序技术研究了不同温度条件下驯化的接种污泥中菌群结构的变化,从而分析温度对厌氧初期挥发性脂肪酸(volatilefattyacids,VFAs)生成的影响。研究结果表明:在中温厌氧条件下,挥发性脂肪酸的产酸效果受厌氧温度的影响。发酵产酸温度提高,有利于厌氧体系有机物的降解以及VFAs生成速率的提高。16rs DNA高通量测序分析结果表明:在中温厌氧条件下,高温驯化有利于梭状芽胞杆菌(Clostridia)、芽胞杆菌(Bacilli)和互营养菌(Synergistia)等菌群丰度的提高,从而提高了厌氧体系纤维素降解以及VFAs的产酸速率。
As a way of resource utilization of livestock farming wastewater,the production of volatile fatty acids(VFAs)from swine wastewater by anaerobic fermentation has attracted more and more attention.But the production process of VFAs from swine wastewater by anaerobic fermentation anaerobic is necessary to be studied in depth.Temperature is one of the important parameters in the VFAs production process.In order to understand the VFAs production process of swine wastewater thoroughly,the effect of fermentation temperature on the yield of VFAs from swine wastewater were studied in an anaerobic sequencing batch reactors heated in a thermostat water bath at the temperature of 25,30,35 and 40℃,respectively.The anaerobic fermentation slurry was sampled hourly within 12 h and the samples were taken once a day.The concentration of VFAs was then measured with chemical titration method.The results exhibit that the fermentation temperature affects the VFAs concentration of the system.The concentration of VFAs in the swine wastewater system under mesophilic anaerobic conditions became stable in 8 h.The maximum concentration of VFAs decreased,but the time for VFAs to reach stable became shorter when the fermentation temperature increased from 25 to 40℃.It meant that the lower fermentation temperature was favourable to yield VFAs,but higher fermentation temperature shortened the span of VFAs production process.The 16rsDNA high-throughput sequencing technology was used to study the changes of bacterial community structure in acclimated inoculated sludge in the anaerobic system at different fermentation temperatures.It was found that the Actinobacteria,Proteobacteria,Synergistia and methanogens(including Methanobacteria and Methanomicrobia)which were common microbial communities could be found in anaerobic environment and Clostridia is the dominant bacterium followed by Bacteroidia in all acclimated inoculated sludge samples at different temperatures.The relative abundance of the mixed microbial culture significantly changed at different temperature and it reflected a significant shift in microbial community structure.When the acclimation temperature of anaerobic sludge increased from 25 to 40℃,the abundance of Bacteroidia decreased,while the abundance of Clostridia,Bacilli and Synergistia increased.The different suitable living environmental temperature for each bacteria could explain the change of the microbial community abundance in the acclimated inoculated sludge.When the temperature was 25℃,it was suitable for Bacteroidia to grow and reproduce,which could use carbohydrates in the system and produce small molecule acids quickly.The temperature was unfavorable to the survival of Synergistia.The VFAs accumulation occured under the combined effect of acidify bacteria and fatty acid-utilizing bacteria.When the temperate increasing,the number of cellulose-degrading bacteria increased,and the hydrolysis rate of cellulose was accelerated.However,the number of bacteria such as Synergistia which could use VFAs also increased.As a result,the concentration of VFAs in the system was reduced and the acid-producing time was shortened.These results meant the increase of temperature could promote the degradation of cellulose in the anaerobic system and the VFAs production rate.
作者
史风梅
徐洪涛
卢玢宇
裴占江
王粟
高亚冰
刘杰
Shi Fengmei;Xu Hongtao;Lu Binyu;Pei Zhanjiang;Wang Su;Gao Yabing;Liu Jie(Rural Energy Institute of Heilongjiang Academy of Agricultural Sciences,Harbin 150086,China;Key Laboratory of Combining Farming and Animal Husbandry,Ministry of Agriculture,P.R.China,Harbin 150086,China;Heilongjiang Key Laboratory of Energy Utilization of Main Crop Straw Resources,Harbin 150086,China)
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2018年第B11期42-47,共6页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家"十三五"重点研发计划课题(2016YFD0501403)
哈尔滨市科技局青年后备人才项目(RC2017QN002097)
关键词
废水
温度
发酵
生猪养殖
挥发性脂肪酸
wastewater
temperature
fermentation
pig breeding
volatile fatty acid
