【作者】 刘荣荣；

【导师】 陈季华；

【作者基本信息】 东华大学 ， 环境工程， 2010， 博士

【摘要】 含PVA的退浆废水具有污染物浓度高、碱度大、难降解性强等特点,这种废水处理起来难度很大,至今在生产实际中还没有找到较好的技术使其达标排放。退浆废水的难处理性以及日益严格的排放要求,使开发经济有效的退浆废水处理技术成为必然。论文针对含PVA的退浆废水的特性,选用改进的HABR反应器来预处理退浆废水,HABR反应器通过增加反应器高度和出水回流来提高反应器捕获微小颗粒污泥的能力以及促进颗粒污泥的形成,从而提高反应器的处理效率,HABR反应器同时具备了EGSB和ABR反应器的优点。本研究来源于横向课题:“蓝岭印染2400吨/日纺织印染废水处理工程设计（课题编号:H20081208）”,并得到东华大学博士学位论文创新基金（项目编号:BC200828）和上海市重点学科建设项目（项目编号:B064）的资助。本文以实际退浆废水为进水,系统研究了HABR反应器的启动;通过正交试验确定了最优运行参数;进行了PVA的厌氧静态试验;讨论了HABR反应器中厌氧颗粒污泥的微生态特征;分析了PVA的降解机理;对HABR反应器稳定运行阶段的数据和HABR反应器的水力特性示踪试验结果进行了分析。本文的试验结果表明:（1）在HABR中直接接种厌氧颗粒污泥,以退浆废水为试验进水,在系统水力停留时间为168h、中温（32±1）℃、进水pH值6.5～8.0、碱度适当偏高条件下,进入反应器废水COD_Cr浓度由1800mg/L逐渐提高到13520mg/L,运行60天后系统COD_Cr去除率均高于45%,并且保持稳定,出水pH值和碱度相对比较稳定,污泥明显呈颗粒状,反应器启动完成。反应器可以在短时间内重新启动,污泥活性很快得到恢复。（2）通过135天的正交试验讨论了不同的进水碱度,出水回流比和水力停留时间对COD、PVA去除率的影响,试验结果表明影响COD、PVA去除率的主次关系为:水力停留时间＞出水回流比＞进水碱度。根据正交试验结果和实际的工程的需要,确定较优的运行方案为:进水碱度500 mg/L、出水回流比94、水力停留时间5天。（3）厌氧颗粒污泥对纯PVA的降解试验表明污泥的微生物组成与粒径大小对PVA降解有影响。碱度过大对PVA的降解不利,但对COD的去除有利。共基质试验表明,以葡萄糖为碳源时,高浓度的葡萄糖抑制PVA的生物降解;以淀粉为碳源时,PVA的降解机理与加入葡萄糖时不同;以豆浆为共基质,PVA需要较长时间才能降解。PVA浓度对厌氧污泥活性的抑制试验表明:当处理废水中的PVA浓度与驯化污泥的废水中PVA浓度相差较大时,则会对污泥的活性产生一定的抑制作用。（4） HABR反应器中厌氧颗粒污泥的微生态特征研究表明:由于颗粒污泥的形成,HABR反应器有较好的COD去除率。HABR各隔室不同的环境（pH、底物类型及浓度）形成了不同的微生物群落,1^#隔室颗粒污泥中的优势菌是利用H₂的产甲烷菌;2^#隔室的颗粒污泥中没有明显的优势菌,菌群多样复杂;3^#隔室的颗粒污泥中以球状菌和长杆状菌占优势;4^#隔室的颗粒污泥中的优势菌是短杆状产甲烷菌。HABR各隔室颗粒污泥利用淀粉、乙酸、丙酸和丁酸的产甲烷活性不同,说明各隔室颗粒污泥的微生物组成不同,前面以产酸菌为主,后面以产甲烷菌为主。HABR反应器中颗粒污泥的辅酶F₄₂₀沿隔室逐渐变化,与产甲烷活性的变化趋势不同,可能是由于各产甲烷细菌的含量不一,因此相关性较差。（5）进出退浆废水的FT-IR、¹H NMR谱图分析结果表明:退浆废水中PVA的分子链在厌氧微生物的作用下发生了断裂,大分子的PVA能在兼氧条件下降解成较简单的中间产物,并且这些中间产物能在好氧条件下进一步矿化。PVA能在厌氧条件下发生有效降解,而且和在有氧条件下的降解机理相类似,但试验条件的不同具体的代谢路径也是有区别的。（6） HABR反应器在平稳运行阶段COD和PVA去除率稳定在42.0%和18.0%左右;最大平均产气量为0.3 L CH₄/g COD去除;出水碱度在700mg/L左右,适合的碱度和pH值是HABR反应器平稳运行的关键。HABR反应器的水力死区较小,它的分散数D/uL在0.105～0.132之间,流态介于理想完全混合式与理想推流式之间,接近理想推流式。更多还原

【Abstract】 Polyvinyl alcohol （PVA）-containing desizing wastewater containing high strength of recalcitrant organic matters and waste alkali are discharged from final textile wastewater. Due to its poor biodegradability, the desizing wastewaters require adequate and sufficient treatment before being allowed to be discharged into surface waters.An improved lab-scale hybrid anaerobic baffled reactor （HABR） was developed to treat desizing wastewater. The modification was achieved by increasing the height of HABR and application of proper effluent recycle, which enabled to increase the ability of entrapping microbe-rich small particles in the reactor and prompted the formation of granules. The reactor combined the advantages of EGSB and ABR simultaneously.This research came from crosswise tasks: "the project design for 2400 t/d textile wastewater treatment of Lanling dying and prting plant" （No. H20081208）. And this work was also supported by the Innovation Foundation of Donghua University for Ph.D. candidates （No. BC200828） and and the Key Subject Construction Item of Shanghai city （No. B064）.First, the paper studied the start-up of HABR and optimization of the operation parameters of HABR; The biodegradation characteristics of PVA 1799 were studied; The structures and micro-ecology characteristics of anaerobic granular sludge in each separation compartment of HABR were studied; The transformation of desizing wastewater in HABR was investigated; the performance of HABR under steady condition was examined and tracer studies were carried out in order to determine the hydrodynamics of HABR.The results indicated;（1） The wastewater was treated on mesophilic condition after anaerobic granular sludge was inoculated in the HABR, the pH of influent was 6.5～8.0 and alkalinity was suitable higher. Hydraulic retention time （HRT） was 168h and the influent concentration was increased from 1800 mg/L to 13520 mg/L gradually during the experiments. The experimental results indicated that the removal of COD_Cr was above 45% and the pH and alkalinity of effluent were relatively stable. At the same time sludge appeared obviously granulation, the start-up was successfully finished. HABR can be restarted-up in a short time and the activities of anaerobic granular sludge can be restored quickly.（2） Within 135 days of the orthogonal experiment for optimization of the operation parameters of HABR, the effect of three important factors including alkalinity of influent, effluent recycle ratio, HRT and each factor at three levels were studied using Taguchi’s method. The results showed that the most important factor contributing to the COD and PVA removal efficiency was HRT followed by effluent recycle ratio and lastly, influent alkalinity. By comprehensively comparing experimental data and considering cost, the optimum condition was chosen as alkalinity of influent 500 mg/L, effluent recycle ratio of 94 times influent rate and HRT 5 d.（3） The biodegradability of PVA 1799 under anaerobic conditions was demonstrated using anaerobic granular sludge from HABR. The results showed that the microorganism composition and particle size of the granular sludge directly influenced the PVA removal rate. Alkalinity influenced degradation of PVA 1799, and high alkalinity suppressed PVA 1799 degradation. It was indicated the degradation of PVA 1799 was suppressed by high glucose concentration; when starch was taken as carbon source, starch molecule first adsorbed on sludge surface and degraded before PVA; It took longer time to degrade PVA 1799 when using soybean milk as carbon source; The inhibition test of PVA concentration on anaerobic granular sludge activity showed: the activity of anaerobic granular sludge was suppressed when PVA concentration between wastewater treated and wastewater for acclimated sludge had larger difference.（4） It was indicated the good removal of COD was achieved probably due to the formation of granular sludge. Hydrogen-utilizing methanogenic bacteria were predominant in interior of granular sludge in compartment 1. As for compartment 2, there were no absolutely predominant bacteria and there were multiple and complicated bacteria communities. In compartment 3, the predominant bacteria were Methanococcus and Methanobacterium. In compartment 4 of the reactor, the predominant bacteria were similar to Methanobrevibacter. The SMA of granular sludge in each compartment of HABR was different when the starch, acetate, propionate and butyrate were taken as substrate respectively. The result indicated the composition of microbe was different in each compartments, acidogenic bacteria were predominant in the front, while methanogenic bacteria were predominant in the rear.The content of coenzyme F₄₂₀ in granular sludge of HABR varied along the reactor, which had no same tendency of variation of SMA, the result maybe due to content of methanogenic bacteria species was different, so it had poor correlation.（5） Judging from the FTIR and ’H NMR analysis of influent and effluent wastewater, it was indicated the molecule chain of PVA fractured in the process of anaerobic biodegradation by the microbes, some of PVA molecules could be facultatively broken down into simple intermediate products. Biodegradation of PVA certainly occurred in an anaerobic environment, which had the same degradation mechanism under anaerobic conditions as that under aerobic conditions, but a different biodegradation pathway might exist under anaerobic conditions due to different experimental conditions. Results of the product analyses confirmed the biodegradation of PVA occurred under anaerobic conditions, it also offered an effective desizing wastewater degradation craft.（6） Under optimum condition （alkalinity of influent 500 mg/L, effluent recycle ratio of 94 times influent rate and hydraulic retention time of 5 d）, the system demonstrated a good performance of COD and PVA removal efficiencies （around 42.0% and 18.0% respectively） and the average concentration of alkalinity in the effluent was around 700 mg/L and pH value was above 6.8. Proper pH and alkalinity were of key importance for the stable operation of HABR. The system at the HRT 5 d had highest observed methane yield averaged at 0.30 L CH4 /g COD removed of HABR. Based on the tracer studies carried out at three different effluent recycle ratio, it was observed that the flow pattern within the HABR remain intermediate between plug and perfectly mixed flows （0.105<D/uL<0.132）; closer to plug flow than completely mixed flow.更多还原