CIC厌氧反应器处理餐厨垃圾的效能与微生态研究

发布时间：2018-03-15 09:25

本文选题：CIC反应器　切入点：餐厨垃圾　出处：《广西师范大学》2017年硕士论文　论文类型：学位论文

【摘要】：随着国民经济的发展,我国餐厨垃圾的总量逐年升高;同时环保要求不断提高,餐厨垃圾的处理逐渐成为人们的研究热点。针对餐厨垃圾的特点,厌氧消化技术具有明显的优势,但其中所含高浓度氨氮与油脂的抑制作用是现今厌氧生物处理中遇到的一个难题,且其抑制的机理还存在争议。本研究将自主设计的可控内循环(CIC)厌氧反应器用于餐厨垃圾的处理,探讨了该反应器的处理效能与工艺参数的优化,并通过静态小瓶试验及反应器内连续式厌氧消化试验,对不同油脂及氨氮浓度对CIC厌氧反应器处理效能的影响及恢复措施进行了研究,同时系统分析了该反应器内厌氧颗粒污泥的理化特性及微生物群落演替情况,得出如下结论:(1)反应器处理效能和工艺参数优化研究。研究了水力停留时间、温度和回流比对CIC厌氧反应器处理效果的影响,通过相应的单因素控制试验并结合将来的工程实际应用情况,确定CIC厌氧反应器处理餐厨垃圾的最佳运行参数为:进水CODcr=5000mg/L,水力停留时间HRT=16h,温度T=25℃,回流比R=3。在此运行条件下,出水CODcr约为650mg/L,CODcr去除率达87%以上,CIC厌氧反应器运行状况良好。(2)在油脂的厌氧消化抑制试验中,通过静态小瓶试验表明,当油脂浓度为2g/L时,厌氧体系的去除效果开始受到抑制,随着油脂浓度的增加,其抑制效果更为明显,CODcr去除率由94%降至27%;出水挥发酸(VFA)含量从5mmol/L上升至9mmol/L。CIC反应器内连续式厌氧消化试验表明,进水油脂浓度为3g/L时产生抑制作用,随着进水油脂浓度的增加,反应器去除效果显著下降,CODcr去除率从94%降至70%,出水VFA从10mmol/L升至25mmol/L以上,出水碱度(ALK)则从102mmol/L降至60mmol/L。厌氧颗粒污泥中疏松型胞外聚合物(LB-EPS)中蛋白质含量从油脂浓度为lg/L时的44.89mg/gVSS增加到3g/L时的71.57mg/gVSS,之后降至7g/L(R=4)时的57.16mg/gVSS;多糖含量由油脂浓度为lg/L时的23.58mg/gVSS增加到3g/L时的57.96mg/gVSS,之后降至7g/L(R=4)时的26.04mg/gVSS。且随着油脂含量增大,EPS的三维荧光谱图中(EEM)类胡敏酸和紫外区类富里酸物质增多,辅酶F420吸收峰变弱,表明油脂对微生物的毒害作用增强,对反应器的抑制作用明显。(3)在氨氮的厌氧消化抑制试验中,静态小瓶试验结果表明,氨氮浓度增加到1000mg/L,CODcr去除效果影响不大;对NH3-N去除影响显著,去除率从40.6%降至7.9%。CIC反应器内连续式厌氧消化试验表明,氨氮浓度从500mg/L升高至1500mg/L时,CODcr的去除率从90%降至76%,NH3-N从20%降至6%左右。随着氨氮浓度升高,LB-EPS中蛋白质含量从38.86mg/gVSS增加到66.41mg/gVSS,多糖含量从50.34mg/gVSS增加到62.37mg/gVSS。EEM分析显示辅酶F420吸收峰逐渐消失,而傅里叶红外谱图(FTIR)中苯环有毒物质增加,表明随着进水氨氮浓度的增加,反应器的去除效果显著降低,氨氮对反应器内微生物产生一定的毒害作用,微生物活性受到抑制。(4)在抑制恢复性措施研究中,分别采取增大内循环与投加生物质炭的措施缓解氨氮及油脂对CIC反应器处理效果的影响。结果显示,在油脂的抑制恢复试验中,进水油脂浓度为3g/L时,增大回流比可将反应器的去除效果回升至初始状态;但当进水油脂浓度升至7g/L时,增大回流比至R=4仍难以将反应器的运行性能恢复,CODcr的去除率只能回升至70%左右,出水VFA仍在25mmol/L以上。在氨氮的抑制恢复试验中,在进水氨氮浓度为1500mg/L时投加生物质炭,CODcr去除率从76%升至90%,NH3-N去除率从6%上升至18%。厌氧颗粒污泥的特性分析表明,LB-EPS中蛋白质含量增加到75.64mg/gVSS,多糖含量提高至68.16mg/gVSS;紫外-可见光谱显示多糖和蛋白吸收峰变强,EEM谱图分析显示辅酶F420吸收峰重新出现,FTIR谱图显示代表多糖和蛋白质的官能团吸收峰变强,说明投加生物质炭后,厌氧颗粒污泥性能得到显著改善,产甲烷菌活性提高,较好地缓解了氨氮对反应器的抑制作用。(5)高通量测序结果表明,在油脂的厌氧消化抑制试验过程中,油脂浓度为3g/L且回流比为2条件下,CIC反应器内的微生物Chaol与香农指数最高,在油脂浓度7g/L时最低;古细菌的群落结构分析中,3g/L条件下和7g/L条件下微生物结构最接近,油脂浓度从 1g/L 增加到 7g/L,Methanobaacteriaceae 从 57.21%降低至 34.4%;对总细菌而言,1g/L条件下和3g/L条件下的群落结构最相似,其中主要为拟杆菌门(Bacteroidetes),其比例随着油脂浓度增加而增大,从1g/L时的29.42%增至7g/L时的52.08%,说明其能较好适应高浓度油脂环境。在氨氮的厌氧消化抑制试验过程中,进水氨氮浓度为1500mg/L未投加生物质炭时微生物物种多样性程度最低,投加生物质炭后最高。氨氮浓度增大到1500mg/L,反应器内古细菌中Methanobacteriaceae由66.3%下降至30.9%,而Methanotrichaceae从32.31%升至46.84%,可推断出Methanobacteriaceae对氨氮较为敏感,Methanotrichaceae则可以适应高浓度的氨氮;对总细菌而言,氨氮浓度增加到1500mg/L,未分类菌从46.2%降至16.1%,而梭菌目(Clostridiales)从2.47%升至28.4%,乳酸杆菌目(Lactobacillales)从0.11%升至27.62%。投加生物质炭后反应器内古细菌中Methanotrichaceaae从62.92%降至 46.84%,Methaanobacteriaceae 从 30.9%降至 17.9%,而 Methanoregulaceae 从 4.83%上升至17.09%;总细菌中未分类菌、梭菌目和乳酸杆菌目三种菌群所占的比例下降,拟杆菌目和厌氧绳菌目所占比例升高。
[Abstract]:With the development of the national economy, the amount of food waste in China increased year by year; at the same time, environmental protection requirements continue to increase, the processing of food waste has become a hot topic of research. According to the characteristics of food waste, anaerobic digestion technology has obvious advantages, but the inhibitory effect of containing high concentration of ammonia nitrogen and oil is a difficulty the anaerobic biological treatment, and the inhibition mechanism is still controversial. This study will be designed independently controllable internal circulation anaerobic reactor (CIC) for the treatment of food waste, discusses the treatment efficiency of the reactor can be optimized and the process parameters, and through the static test and vial continuous anaerobic reactor the digestive experiment, effects of different oil and ammonia concentration on CIC anaerobic reactor treatment efficiency and recovery measures were studied, and the systematic analysis of the reactor of anaerobic granular sludge treatment Chemical properties and microbial community succession, draw the following conclusions: (1) study on the performance and optimization of process parameters of the reactor. The hydraulic retention time, temperature and reflux ratio on the treatment effect of CIC anaerobic reactor, through the single factor test and the corresponding control combined with the future engineering application, determine the optimum operation the parameters of the CIC anaerobic reactor for the treatment of food waste water: CODcr=5000mg/L, hydraulic retention time HRT=16h, temperature T=25, reflux ratio of R=3. in this condition, the effluent CODcr was about 650mg/L, the CODcr removal rate is above 87%, the operation status of CIC anaerobic reactor. (2) in anaerobic digestion of fat suppression test. Through the static vial test showed that when the oil concentration is 2g/L, the removal effect of anaerobic system began to be restrained, with the increase of oil concentration, the inhibitory effect is more obvious, the removal rate of CODcr From 94% to 27%; the effluent volatile fatty acid (VFA) content increased from 5mmol/L to 9mmol/L.CIC in the reactor continuous anaerobic digestion test showed that the oil inlet concentration of 3g/L inhibited, along with the increase of influent oil concentration, removal efficiency of the reactor decreased significantly, CODcr removal rate decreased from 94% to 70%, the effluent VFA from 10mmol/L above 25mmol/L, the effluent alkalinity (ALK) from 102mmol/L to 60mmol/L. in anaerobic granular sludge loose type of extracellular polymers (LB-EPS) protein content from the oil when the concentration of lg/L 44.89mg/gVSS increased to 3g/L 71.57mg/gVSS, then to 7g/L (R=4) is 57.16mg/gVSS; the content of Polysaccharide by lipid concentration of lg/L 23.58mg/gVSS increased to 3g/L 57.96mg/gVSS, then to 7g/L (R=4) of the 26.04mg/gVSS. and with the oil content increased, the three-dimensional fluorescence spectrum of EPS (EEM) in the class of Hu Min acid and ultraviolet rich compounds In the acid substances increased, coenzyme F420 absorption peaks become weak, showed that the grease on the toxicity of microbes increased, inhibition of the reactor is obvious. (3) in anaerobic ammonia inhibition test, static flask test results showed that the ammonia concentration increased to 1000mg/L, CODcr removal has little effect on NH3-N removal significantly; effect of removal rate from 40.6% to 7.9%.CIC in the reactor continuous anaerobic digestion test showed that the ammonia concentration increased from 500mg/L to 1500mg/L, the removal rate of CODcr from 90% to 76%, NH3-N from 20% to 6%. With the ammonia concentration was increased, the protein content in LB-EPS increased from 38.86mg/gVSS to 66.41mg/gVSS, the content of Polysaccharide from 50.34mg/gVSS increase to 62.37mg/gVSS.EEM analysis showed that coenzyme F420 absorption peak gradually disappeared, and Fourier transform infrared spectroscopy (FTIR) in benzene toxic substances increased, showed that with the increase of influent ammonia concentration, anti The effect should be removed is significantly reduced, ammonia nitrogen produced a toxic effect on microbes in the reactor, microbial activity was inhibited. (4) in the inhibition of recovery measures were taken in the study, increasing circulation and adding biochar measures to alleviate the effects of ammonia and grease on the CIC reactor. The results showed that the treatment effect in the oil recovery, inhibition test, water oil concentration is 3g/L, the reflux ratio will increase the removal efficiency of reactor recovered to the initial state; but when the influent oil concentration to 7g/L, increasing the reflux ratio to R=4 is still difficult to reverse the performance should be restored, the removal rate of CODcr can be increased to about 70% still, the effluent VFA above 25mmol/L. Recovery in ammonia inhibition test, the influent ammonia concentration was 1500mg/L adding biomass charcoal, the removal rate of CODcr increased from 76% to 90%, the removal rate of NH3-N increased from 6% to 18%. anaerobic heart Analysis shows that the characteristics of granular sludge, the protein content in LB-EPS increased to 75.64mg/gVSS, increase the content of polysaccharide to 68.16mg/gVSS; UV Vis spectra showed absorption peak of polysaccharide and protein strong EEM spectra analysis showed that coenzyme F420 absorption peak appears again, the FTIR spectra showed that the functional groups on behalf of polysaccharide and protein absorption peaks become strong that, adding the biomass carbon after anaerobic granular sludge performance can be improved significantly, improve the methanogenic activity, better alleviate the inhibitory effect of ammonia on the reactor. (5) Gao Tongliang sequencing results showed that the inhibition of anaerobic digestion of fat during the test, the oil concentration is 3g/L and reflux ratio of 2 conditions. Microbial Chaol and Shannon index of CIC reactor, the highest, lowest in oil concentration 7g/L; analysis of community structure of archaea, under the conditions of 3g/L and 7g/L under the condition of microbial structure to the oil concentration from 1g/L To 7g/L, Methanobaacteriaceae decreased from 57.21% to 34.4%; the total bacterial community structure, under the condition of 1g/L and 3g/L under the condition of the most similar, mainly for the Bacteroidetes (Bacteroidetes), the ratio increases with the increase of oil concentration, from 1g/L 29.42% to 7g/L 52.08% increase, the better to adapt to the high concentration of oil in anaerobic environment. Inhibition of ammonia during the experiment, the influent ammonia concentration was 1500mg/L without adding biochar when microbial species diversity and the lowest level of adding biochar. The highest ammonia concentration increased to 1500mg/L, the reactor of ancient bacteria Methanobacteriaceae decreased from 66.3% to 30.9%, and from 32.31% to Methanotrichaceae 46.84%, can be inferred that Methanobacteriaceae is sensitive to ammonia, Methanotrichaceae can adapt to the high concentration of ammonia; the total bacteria, ammonia concentration Unclassified bacteria increased to 1500mg/L, fell from 46.2% to 16.1%, and clostridiales (Clostridiales) from 2.47% to 28.4%, Lactobacillus orders (Lactobacillales) from 0.11% to 27.62%. after adding biochar Methanotrichaceaae reactor of ancient bacteria from 62.92% to 46.84%, Methaanobacteriaceae from 30.9% to 17.9%, while the Methanoregulaceae increased from 4.83% to 17.09%; bacteria unclassified total bacteria, which accounted for clostridiales and Lactobacillus. Three kinds of bacteria decreased the proportion of Bacteroides and anaerobic bacteria increased the proportion of rope mesh.

【学位授予单位】：广西师范大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X799

【参考文献】