【作者】 方俊华；

【导师】 龙腾锐；

【作者基本信息】 重庆大学 ， 市政工程， 2010， 博士

【摘要】 苯胺基乙睛生产废水是一种高浓度难生化降解的有毒有机废水。其主要成分为苯胺类物质及氰化物,毒性强,危害大,处理难度大。本研究从原水水质分析入手,找到了一个适合水质特性的的苯胺类分析方法;从膨润土的提纯、改性、处理废水等试验方法入手,对膨润土进行了钠改性、铁交联改性,并对未经改性的原样与改性产物的矿物微结构和物理化学性质进行了分析研究,阐明了膨润土改性以后,其物理化学性质和矿物微结构变化之间的关系;对铁交联膨润土作为促进剂与H₂O₂联合预处理苯胺基乙腈生产废水进行了研究,取得了最优运行参数,并对其反应机理进行了探讨;进而对预处理出水采用两相两级厌氧反应器进行处理的试验设计、启动、稳定运行及其生物相开展了研究。由于此类废水成分复杂,检测过程中会相互干扰,特别是在测定废水中存在的苯胺类化合物时更是如此。故首先研究了该废水中苯胺类化合物检测方法的研究。通过多次试验,利用紫外分光光度法在偏酸条件下直接进行测定,无须蒸馏。当苯胺浓度在0³4.00 mg/L时,在230nm处测定苯胺浓度与吸光度可呈良好的线性关系,相关系数为r=0.9998,加标回收率为98.55%～100.61%,平均回收率为R=99.59%,对干扰物的考察显示相对标准偏差在4.16%⁵.00%,在可接受范围内。因此本研究采用此法测定实验过程中的苯胺类化合物。在废水预处理研究中,首先以原膨润土矿为原料,在经过提纯后,采用微波辐射法制备了钠化膨润土,得出的膨润土钠化的工艺条件为:以NaCl为钠化改性剂,改性剂用量与膨润土投加量比为0.6:5（g/g）,溶剂使用量与膨润土投加量比7:5（ml/g）,反应时间为4min。试验结果表明,制备所得的钠基膨润土的阳离子交换容量由62.4mmol/100g土提高到93mmol/100g土,有利于后续的铁交联柱撑改性。其次以钠基膨润土为原料,尝试采用铁交联膨润土与H₂O₂联合氧化处理苯胺基乙腈废水,并考察其对污染物的去除性能。试验结果表明,铁交联膨润土-H₂O₂氧化法对废水的处理能力大大提高,铁交联膨润土-H₂O₂氧化吸附处理苯胺基乙腈废水的较适宜的工艺条件为:废水pH值为4.0、过氧化氢投加量为6.66g/L、交联膨润土投加量为20g/L、处理温度为30℃、处理时间为60min,COD_cr及苯胺的去除率分别达到了40.6%及92.6%,苯胺含量低于500mg/L,可生化性BOD₅/COD_cr提高到0.32左右,基本上可满足了后续生化处理进水的要求。同时,论文对铁交联-H₂O₂氧化法处理苯胺基乙腈废水进行了动力学研究。在制备改性膨润土的过程中,分别采用X-射线衍射,红外光谱,电镜扫描比较研究了钠化膨润土和铁交联膨润土结构方面的变化。结果表明,经过铁交联后,膨润土的层间距大于钠化膨润土;在红外光谱分析中,铁交联膨润土出现了新的特征峰,扫描电镜分析结果进一步说明了膨润土经过改性后,其表面填塞了改性基团,使得改性后的膨润土处理废水的性能提高,从而说明膨润土经过改性后结构及性质上的变化是有利于处理苯胺基乙腈生产废水。在两相厌氧处理试验中,首先将原废水进行稀释,加入从重庆钢铁公司焦化厂兼氧段取回的污泥进行接种培养,使进水浓度逐步提高,将产甲烷相分为两级运行方式,使污泥渐渐适应此类废水。在驯化成功后,对影响两相厌氧系统的重要因素:温度、PH、HRT和容积负荷的最适范围做了试验性研究,结果表明,产酸相最佳运行条件为:T=30～35℃,pH=6.0～6.5,HRT=24h,容积负荷=7.95kgCOD_cr/m3d;产甲烷相反应器运行条件为:T=30～35℃,pH=8.0～8.5,HRT=48h,产甲烷一级容积负荷为4.65kgCOD_cr/m3d,产甲烷二级容积负荷为3.38kgCOD_cr/m3d。在两相厌氧最佳运行条件下,COD_cr处理效果可达到67%。同时,对生化段中各反应器中的污泥絮体结构和微生物相进行了观测,从污泥絮体结构看,产酸相污泥絮体比较松散,而甲烷相的絮体则比较密实。产酸相和产甲烷相污泥中的微生物主要是:产酸相微生物以杆菌、梭菌和弧菌属为主,产甲烷相微生物以产甲烷球菌属、产甲烷丝菌属和产甲烷杆菌属为主。最后,本研究在上述运行条件下,以物化段出水作为两相厌氧处理工艺的进水进行了研究,结果表明:苯胺的去除率可达到50%以上,COD_cr去除率为68%左右,生化段进水COD_cr均值从25000mg/L降至平均8000mg/L。同时发现,只有产酸相对苯胺有去除效果,产甲烷相对苯胺几乎没有去除效果。更多还原

【Abstract】 N-phenylglycinonitrile chemical wastewater is one of the refractory wastewater with high concentration, low biodegradability and high toxicity; the main components are anilines and cyanides which are harmful to organisms at low concentration ,difficult to treat and classed as hazardous pollutants. It was started from the raw water quality analysis, and found an aniline analysis method suitable for water quality characteristics in this study; from the experiment methods of bentonite purified,modified,wastewater treatment,and modified by cross-linking modification of sodium and iron,the mineral microstructure,physical and chemical properties of the unmodified or modified products were analyzed; it also explain its physical and chemical properties and mineral micro-structure of the relationship between changes after the bentonite was modified; montmorillonite iron and H₂O₂ combined as a promoter of aniline-acetonitrile wastewater pretreatment was studied, the optimal operating parameters were obtained, and the reaction mechanism was discussed; and then the experimental design, starting and stable operation of the research ,with the effluent at the pretreatment levels which was treated by two-phase anaerobic reactor was undertaken .As the complexity of the wastewater components, the detection process will interfere with each other,especially for the detection of the anilines existing in the wastewater. Therefore, the detection method of the aniline compounds in wastewater was studied firstly.So change the way to a more secure and more feasible method, it is the ultraviolet spectrophotomety, at pH=6.6, the aniline is determined at 230nm. It has a good linear relationship when the concentration of aniline range from 0³4.00 mg/L , related coefficients is 0.9998. The relative standard deviation of aniline is less than 5.0%, the rates of recovery of aniline is 98.55%～100.61%, so the results are satisfactory. Therefore, this method for the detection of anilines was used in the experiments.During the research of the wastewater pretreatment ,firstly, using Ca-bentonite as raw material, Na-bentonite was prepared by microwave radiation after purification, and the preparation conditions were as follows: using NaCl as modified regents,the reagent volume of 50% C₂H₅OH to the bentonite quality is 7:5（ml/g）and the reaction time is 4min, the experimental results showed that the CEC of Na-bentonite increased to 93mmol/100g after modification from 62.4mmol/100g which is useful to the Fe-pillared modified.Secondly, Na-bentonite is used as raw material.For the wastewater treatment limitation of organo-bentonite, using the Fe-pillared bentonite and H₂O₂ to treat the N-pHenylglycinonitrile chemical wastewater by oxiditon was tried, and the removal ability was investigated,too. The experimental results showed that the optimal treatment conditions were obtained as follows: pH value is about 4.0, added amount of H₂O₂ is 6.66g/L, amount of Fe-pillared bentonite added is 20g/L, temperature is 30℃,and treatment time is 60min, the removal rates of the COD_cr and aniline can reach 40.6%, 92.6% and the content of aniline is less than 500mg/L,the BOD₅/COD_cr increases to 0.32 which meets to the requirement of subsequent biochemical treatment. The effect of oxidation method by Fe-pillared bentonite and H₂O₂ had been improved effectively. Simultaneously, the reaction kinetics was studied.The structures of Na-bentonite, and Fe-pillared bentonite was investigated by XRD, IR and SEM respectively. Studies on X-ray diffraction date （XRD） demonstrated that the interlayer spacing was obviously enlarged through Fe-crosslinked modification; the results of infrared spectrum （IR） discovered that some new characteristic peaks appeared, and the basic structure didn’t destroy; SEM indicated that the bentonite surface was packed with the modified groups via, which improved the treatment effect, therefore, the change of structure and properties of bentonite were useful to the treatment efficiency during modification.During the experiments of two-phase anaerobic treatment, firstly the original wastewaterwas diluted, accession the sludge from Coking Plant of ChongQing Iron and Steel Company ,then the sludge was inoculation cultured, to gradually increase the concentration of the influent,and the methanogenic phase was divided into two modes to run to gradually adapt to the wastewater sludge. After the success of the cultivation, the most proper value ranges of some important effect factors of this bio-chemical system had been determined. Fore phase of acid producing the proper condition is T=30～35℃,pH=6.0～6.5 HRT=24h and the capacity burden is 7.95COD_cr/m3d; fore phase of methane producing the condition is T=30～35℃,pH=8.0～8.5, HRT=48h, and the capacity burden of the two stages of methane producing are 4.65kgCOD/m3d and 3.38kgCOD/m3d respectively. In the two-phase anaerobic best running conditions, the treatment effect can be achieved67%. Simultaneously, the sludge flocculation body and the image of the microbe of bio-chemical stage had been studied. For the fragment of the sludge flocculation body, the sludge flocculation body from phase of acid producing compare with the phase of methane producing is more incompact, the microbe are exposed on the surface of the sludge contrast with the phase of methane producing. Fore the image of microbe, the main microbe in phase of acid producing are bacillus、Clostriolium and vibrio, on the other hand the methanococcus is the most contribution of the microbe in the phase of methane producing, there still have some methanobacterium been found.At last, under the operating conditions in the study,the outlet of physic-chemical stage had been put into the two-phase anaerobic stage for several periodicities, the data shows that the removal rate of aniline compound is 50% and the COD_cr is about 68%, and the removal of aniline is contributed only by the phase of acid producing but almost not by the phase of methane producing.更多还原