摘要
在中温(36℃)条件下,进行了猪粪干式厌氧消化中试试验,以探索系统运行过程中氨氮的变化规律。研究表明,厌氧微生物没有足够的驯化时间,对氨氮的耐受力较低。为促进厌氧微生物对高浓度氨氮的耐受力,进行消化液回流以逐渐提高氨氮浓度。但是持续快速升高的氨氮浓度会造成氨氮抑制,为防止这种现象的发生,对出料进行固液分离后只进行沼渣回流,氨氮浓度稳定在5 000 mg·L^(-1)。为了进一步考察氨氮的变化规律再次变为回流消化液,系统氨氮浓度逐渐升高达到6 000 mg·L^(-1),沼气产量由38 m^3·d^(-1)降为28 m^3·d^(-1)。说明沼渣回流比消化液回流对系统氨氮浓度能起到更好地控制作用。另外,酸碱比(VFA/TA)是否能作为系统稳定性指标,也会受到氨氮浓度的影响。
A pilot experiment of swine manure dry anaerobic digestion was carried out under the mesophilic（36 ℃） condition,to explore the change rule of ammonia nitrogen concentration in the system.The results showed the anaerobic microbes cannot tolerant high ammonia nitrogen because short of domestication time.Digestion liquid was at first back-flowed to improve the tolerance to ammonia nitrogen gradually.However,sustained rapid increase in ammonia concentration will cause ammonia inhibition.To prevent the occurrence of this phenomenon.only the biogas residue was recycled after the solid-liquid separation of discharging for the inhibition of high ammonia nitrogen.Finally,ammonia nitrogen concentration was around 5 000 mg·L^-1.To further investigate the variation rule of ammonia nitrogen,digestion liquid was back-flowed again and ammonia nitrogen reached to 6 000 mg·L^-1 gradually.Then the biogas production dropped from 38 m^3·d^-1 to 28 m^3·d^-1.It displayed that the return of biogas residue could be better to control total ammonia nitrogen concentration comparing to the return of digestion liquid.In addition,whether the ratio（VFA/TA） can be used as the stability index of the system will also be affected by the concentration of ammonia nitrogen.
出处
《科学技术与工程》
北大核心
2017年第32期181-186,共6页
Science Technology and Engineering
基金
国家水体污染控制与治理科技重大专项(2014ZX07114)
北京市自然科学基金科技重点项目(KZ201310016017)资助
关键词
猪粪
干式厌氧消化
氨氮抑制
沼渣回流
消化液回流
swine manure
dry anaerobic digestion
ammonia inhibition
return of biogas residue
return of digestion liquid
