本文選題：剩余污泥 + 堿性厭氧發(fā)酵�。� 參考：《哈爾濱工業(yè)大學(xué)》2015年碩士論文

【摘要】：隨著污水處理規(guī)模的不斷增加,污泥的產(chǎn)量越來越多,污泥的處理與處置問題已經(jīng)成為污水處理領(lǐng)域的重點(diǎn)和難點(diǎn)問題。污泥厭氧發(fā)酵過程中產(chǎn)酸階段能夠產(chǎn)生大量的揮發(fā)性脂肪酸,這些脂肪酸能夠作為強(qiáng)化生物脫氮除磷過程中的碳源,解決脫氮除磷工藝運(yùn)行過程中碳源不足這一矛盾。雖然目前污泥堿性產(chǎn)酸的研究較多,但是關(guān)于堿性發(fā)酵過程中,各有機(jī)物的降解規(guī)律并無詳細(xì)闡述;微生物種群演替規(guī)律與脂肪酸積累之間的關(guān)系缺乏深入研究;對于發(fā)酵后污泥作為種泥對污泥產(chǎn)氣性能的影響研究較少。本研究采用EGSB反應(yīng)器,條件控制中溫(35±1℃)和p H=10,研究有機(jī)物的變化規(guī)律、氮和磷的釋出和污泥的減量效果,同時(shí)測定了揮發(fā)性脂肪酸的產(chǎn)量和各酸的分布,找出了剩余污泥最佳污泥水解發(fā)酵產(chǎn)酸時(shí)間,并討論了污泥堿性發(fā)酵后,剩余污泥作為種泥對污泥產(chǎn)氣效果的影響。最后通過高通量測序,分析剩余污泥在堿性發(fā)酵過程中微生物的演替規(guī)律,從微生物的角度揭示了堿性條件促進(jìn)污泥產(chǎn)酸的機(jī)理。研究表明,反應(yīng)器內(nèi)SCOD在發(fā)酵周期內(nèi)含量逐漸增大,并且前8天的增勢更明顯,氨氮、正磷酸鹽和總揮發(fā)性脂肪酸在發(fā)酵周期的前8天濃度逐漸升高,之后隨污泥停留時(shí)間的延長含量逐漸降低。根據(jù)實(shí)驗(yàn)結(jié)果確定8天為反應(yīng)器最佳的污泥水解酸化時(shí)間。揮發(fā)性脂肪酸主要由乙酸、丙酸、異丁酸、正丁酸、異戊酸和正戊酸組成,并且乙酸的含量始終是最大的,占到了總揮發(fā)酸量的82%左右,緊隨其后的是丙酸,其占總揮發(fā)酸量的12%左右,其余四中揮發(fā)酸的總量僅占總揮發(fā)酸的5%左右。這與高通量測序結(jié)果中菌群的結(jié)構(gòu)組成是對應(yīng)的。TCOD、SS和VSS在發(fā)酵周期內(nèi)均呈現(xiàn)逐漸減少的趨勢。在剩余污泥的整個(gè)發(fā)酵周期內(nèi),有將近20%的TCOD被去除。SS和VSS在發(fā)酵周期的前8天減量比較明顯,之后降勢較為緩慢,8 d是較為經(jīng)濟(jì)合適的污泥減量發(fā)酵時(shí)間。發(fā)酵8天后的剩余污泥作為種泥,其產(chǎn)氣量高于原污泥和發(fā)酵2天的污泥。剩余污泥中堿性發(fā)酵過程中,Firmicutes、Proteobacteria和Actinobacteria這三個(gè)門類細(xì)菌為主要菌種,其總百分含量在發(fā)酵周期內(nèi)呈現(xiàn)先增大后減小的規(guī)律,在發(fā)酵開始后第2天時(shí)達(dá)到最高94.6%,發(fā)酵8天時(shí)的百分含量為87.7%。污泥停留時(shí)間為8天時(shí),Clostridia的含量最大,其次為Actinobacteria,Anaerolineae和Betaproteobateri的含量次之。污泥停留時(shí)間超過8天時(shí),會導(dǎo)致含有許多致病菌的Gammaproteobateria的大量繁殖。在發(fā)酵周期的前8天,TVFAs和總產(chǎn)酸菌均隨發(fā)酵時(shí)間的延長而增長,兩者呈正相關(guān)關(guān)系,8天為最適污泥堿性厭氧發(fā)酵產(chǎn)酸時(shí)間。Clostridium、Bacillus、Amphibacillus和Peptostreptococcaceae為剩余污泥厭氧產(chǎn)VFAs過程中的優(yōu)勢菌群。總產(chǎn)酸菌屬中大多數(shù)的菌屬發(fā)酵產(chǎn)乙酸,另外的菌屬產(chǎn)混合脂肪酸,因此乙酸在TVFAs中所占比例最大。
[Abstract]:With the increasing scale of sewage treatment, the output of sludge is increasing, and the treatment and disposal of sludge has become a key and difficult problem in the field of sewage treatment. A large amount of volatile fatty acids can be produced during the acidizing stage of anaerobic fermentation of sludge. These fatty acids can be used as carbon sources in the process of enhancing biological nitrogen and phosphorus removal, and the contradiction of insufficient carbon sources in the process of denitrification and phosphorus removal is solved. Although there are many studies on alkaline acid production in sludge, the degradation law of organic matter in alkaline fermentation process is not elaborated in detail, and the relationship between microbial population succession and fatty acid accumulation is not thoroughly studied. There is little research on the effect of sludge as seed sludge on sludge gas production. In this study, EGSB reactor was used to control medium temperature (35 鹵1 鈩，

本文編號：1992229