Fenton-曝气生物滤池深度处理柠檬酸废水中试

柠檬酸废水(二级出水)具有可生化性差,难生物降解的特点,可采用Fenton氧化-曝气生物滤池组合工艺进行处理。试验表明:当H2O2投加量为最优化条件下的0.6m L/L时,Fenton氧化-曝气生物滤池组合工艺对COD有着良好并且稳定的去除效果。其中,Fenton起到改善废水可生化性作用,通过去除废水中的类腐殖酸、类富里酸组分,可以将废水ρ(BOD5)/ρ(COD)从0.26增加到0.75,后续曝气生物滤池继续对COD进行生物降解,组合工艺在15 d的连续运行条件下,COD去除率稳定在85%以上,出水ρ(COD)<50 mg/L。     

柠檬酸生产物废水处理工艺及展望

柠檬酸在我国行业应用中较为广泛,但由此产生的废水不容忽视.本文通过柠檬酸废水来源及水质状况分析,就光合细菌法、乳状液膜法、生产饲料酵母法和Fenton试剂氧化法四种工艺优点和不足以及实践运用进行详细论述,并对工艺发展方向进行了简要展望.     

柠檬酸中和废水回用技术研究

本文研究了柠檬酸中和废水回用工艺技术。中和废水经碱（ＮａＯＨ）沉淀和酸（Ｈ２ＳＯ４）中和预处理措施，直接用于发酵配料。实验用菌株Ｃ－９８自黑曲霉ＣＢＸ－１２分离获得。最佳发酵条件：总还原糖１４％￣１６％，麦麸２．５％，初始ｐＨ６．５，乙醇１．５％，同传统的柠檬酸废水处理工艺比较，该工艺在投资和运转成本方面具有潜在的优势。     

生物膜法处理柠檬酸废水的研究

针对柠檬酸废水可生化性差、成分复杂等特点,采用生物膜法进行处理.实验结果表明：该工况对COD、NH3-N具有较好的去除效率,去除率分别为93％、97％,达到《污水综合排放标准》（GB8978-1996）一级标准.     

印染废水回用的反渗透预处理技术

针对印染废水回用时水中有机物浓度、盐度和色度高等问题,以苏南某污水处理厂中试试验基地(70%以上为印染废水)二级生化出水为研究对象,对混凝沉淀-超滤(以下称组合工艺1)、BAC(生物活性炭滤池)-超滤(组合工艺2)和混凝沉淀-BAC-超滤(组合工艺3)3种工艺进行比较研究,系统考察其作为反渗透预处理技术的可行性. 结果表明:组合工艺3对印染废水二级生化出水中COD_Cr、TCU(真色)及浊度的平均去除率分别为53.0%、49.2%和99.5%,UV₂₅₄下降了50.0%,均高于其他2个组合工艺. 对超滤膜表面污染阻力分布的测定可知,组合工艺3中不可逆污染造成膜污染的程度最轻. 此外,3种组合工艺的出水通过反渗透装置后的平均脱盐率分别为98.0%、97.5%和98.2%. 可见,针对该研究中涉及的二级生化出水,组合工艺3预处理工艺是反渗透预处理的最佳工艺.      

柠檬酸生产废水的治理

我国是世界上最大的柠檬酸生产和出口国，柠檬酸也是我国最大的生物出口产品，柠檬酸生产过程产生的大量高浓度有机废水引起的环境问题，长期以来一直是制约行业发展的主要因素之一。本文总结了柠檬酸生产废水治理的经验和问题，希望能给柠檬酸等高浓度有机废水的治理和环保管理提供一些帮助。     

生化燃料综合废水处理改扩建工程

某生化燃料综合废水处理改扩建工程采用"上旋流厌氧IC反应器和一体式氧化沟"主体工艺处理柠檬酸废水和综合废水,原水COD浓度在10 000~30 000 mg/L,经上旋流厌氧IC反应器处理后出水COD在2 000~2 500 mg/L,经一体式氧化沟处理后出水COD在200~250 mg/L,稳定达到排放标准:ρ(COD)≤300 mg/L。     

曝气生物滤池组合工艺处理肉类加工废水生产性试验研究

以实际工程调试为依据,阐述了曝气生物滤池组合工艺的原理和特点,通过运行结果分析及运行费用核算得出结论:该套组合工艺对地处北方的肉类加工企业,是一个技术可行、比较经济的废水处理方案     

强化混凝与Fenton试剂氧化处理含聚采油废水的中试研究

采用强化混凝加Fenton试剂氧化技术组合工艺研究其对含聚采油废水的处理效果。分别考察了混凝反应pH及混凝药剂投加浓度和Fenton试剂氧化反应中H2O2以及Fe2+的投加浓度对含聚采油废水处理效果的影响。试验结果表明,在最佳反应条件下,废水的COD达到48 mg/L,SS达到9 mg/L,色度达到16倍,能够达到GB 8978—1996《污水综合排放标准》一级排放标准。强化混凝加Fenton试剂氧化技术组合工艺对含聚采油废水具有良好的处理效果。     

利用光合细菌处理柠檬酸废水

利用光合细菌处理柠檬酸废水南通发酵厂管希夷，王济生南通市发酵厂与上海交通大学生物技术研究所在日本小栋正泰先生的帮助下，进行了利用光会细菌处理柠檬酸废水的大量试验，并建立了日处理！５０～ｓ００ｔ柠檬酸废水的装置，但由于仍有明显不足之处，该厂大胆采用了新...     

Distribution and ecological effect of mercury in Laogang landfill, Shanghai, China

Laogang landfill near Shanghai is the largest landfill in China, and receives about 10000 t of daily garbage per day, Samples of topsoil and plants were analyzed to evaluate mercury pollution from the landfill. For topsoil samples, there were significant correlations among total mercury （HgT）, combinative mercury （Hgc） and gaseous mercury （HgG）, and content of total organic carbon （TOC）, but, no significantly relationship was found between Hg content and filling time. Hg content changes in vertical profiles with time showed that the average Hgv of profiles 1992, 1996, and 2000 was similar, but their average HgG was quite different. HgT was significantly correlated with Hgc in profile 1992 and 2000, and Hgv was significantly correlated with Hg6 in profile 1996. HgG/Hgv ratio in profile samples decreased in the order of （HgG,/HgT）1992〉（HgG/HgT）1996〉〉（HgG/HgT）2000. A simple outline of Hg release in landfill could be drawn： with increasing of filling time, degradation undergoes different biodegradation, accordingly, gaseous mercury goes through small, more, and small proportion to total mercury. Distribution of Hg in plants was inhomogeneous, following the order of leaf〉root〉stem. The highest value of leaf may be associated with higher atmospheric Hg from landfill. Ligneous plants （e.g. Phyllostachys glanca, Prunus salicina and Ligustrum lucidum） are capable of enriching more Hg than herbaceous plants.     

EDTA-enhanced phytoremediation of lead contaminated soil by Bidens maximowicziana

Phytoremediation is a potential cleanup technology for the removal of heavy metals from contaminated soils.Bidens maximowicziana is a new Pb hyperaccumulator,which not only has remarkable tolerance to Pb but also extraordinary accumulation capacity for Pb.The maximum Pb concentration was 1509.3 mg/kg in roots and 2164.7 mg/kg in overground tissues.The Pb distribution order in the B. maximowicziana was:leaf>stem>root.The effect of amendments on phytoremediation was also studied.The mobility of soil Pb and the Pb concentrations in plants were both increased by EDTA application.Compared with CK(control check),EDTA application promoted translocation of Pb to overground parts of the plant.The Pb concentrations in overground parts of plants was increased from 24.23-680.56 mg/kg to 29.07-1905.57 mg/kg.This research demonstrated that B.maximowicziana appeared to be suitable for phytoremediation of Pb contaminated soil,especially,combination with EDTA.     

Decomposition of alachlor by ozonation and its mechanism

Decomposition and corresponding mechanism of alachlor, an endocrine disruptor in water by ozonation were investigated. Results showed that alachlor could not be completely mineralized by ozone alone. Many intermediates and final products were formed during the process, including aromatic compounds, aliphatic carboxylic acids, and inorganic ions. In evoluting these products, some of them with weak polarity were qualitatively identified by GC-MS. The information of inorganic ions suggested that the dechlorination was the first and the fastest step in the ozonation of alachlor.     

Enzymatic oxidation of aqueous pentachlorophenol

The influence of the nonionic surfactant Tween 80 on pentachlorophenol （PCP） oxidation catalyzed by horseradish peroxidase was studied. The surfactant was tested at concentrations below and above its critical micelle concentration （CMC）. Enhancement of PCP removal was observed at sub-CMCs. The presence of Tween 80 in the reaction mixture reduced enzyme inactivation which occurred through a combination of free radical attack and sorption by precipitated products. A simple first-order model was able to simulate time profiles for enzyme inactivation in the presence or absence of Tween 80. At supra-CMCs, the surfactant caused noticeable reductions in PCP removal, presumably through micelle partitioning of PCP which precluded the hydrophobic PCP molecule from interacting with the enzyme.     

基于综合水质标识指数和对应分析法的校园河道水质评价

以三峡大学的校园河道求索溪为研究对象,利用综合水质标识指数法确定求索溪水质类别,分析其水质时空变化规律,并利用对应分析法得出求索溪中不同监测点的主要污染因子.研究结果表明:求索溪整体的综合水质标识指数为7.423,整体水质为劣V类(地表水环境质量标准GB 3838-2002)且黑臭.从时间变化来看,求索溪4月份的水质最差,5月份次之,4、5月份所有监测点的水质都劣于V类且黑臭;8月份水质最好,水质为Ⅳ类;从空间分布来看,8个监测点综合水质标识指数均超过6.0,水质为劣V类,其中6号监测点的水质相对最好,监测点3号的水质相对最差;对应分析法得出求索溪的整体水体污染程度受总氮因子的影响最大,其次为总磷.该研究拟为求索溪及类似校园河道的水环境治理研究提供基础依据和参考.     

Effects of chitosan on growth of an aquatic plant (Hydrilla verticillata) in polluted waters with different chemical oxygen demands

Effects of chitosan on a submersed plant, Hydrilla verticillata, were investigated. Results indicated that H. venicillata could prevent ultrastructure phytotoxicities and oxidativereaction from polluted water with high chemical oxygen demand (COD). Superoxide dismutase (SOD) activity and malondialdehyde (MDA) contents in H. verticillata treated with 0.1% chitosan in wastewater increased with high COD (980 mg/L) and decreased with low COD (63 mg/L), respectively. Ultrastructural analysis showed that the stroma and grana of chloroplast basically remained normal. However, plant cells from the control experiment (untreated with chitosan) were vacuolated and the cell interval increased. The relict of protoplast moved to the center, with cells tending to disjoint. Our findings indicate that wastewater with high COD concentration can cause a substantial damage to submersed plant, nevertheless, chitosan probably could alleviate the membrane lipid peroxidization and ultrastructure phytotoxicities, and protect plant cells from stress of high COD concentration polluted water.     

Removal of cadmium using MnO2 loaded D301 resin

MnO2 loaded weak basic anion exchange resin D301 （Anion exchange resin, macroreticular weak basic styrene） as adsorbent has been prepared and applied to the removal of cadmium. The adsorption characteristics have been investigated with respect to effect of pH, equilibrium isotherms, removal kinetic data, and interference of the coexisting ions. The results indicated that the Cd^2＋ could be efficiently removed using MnO2 loaded D301 resin in the pH range of 3-8 from aqueous solutions with the co-existence of high concentration of alkali and alkaline-earth metals ions. The saturate adsorption capacity of the Cd^2＋ was 77.88 mg/g. The adsorption process followed the pseudo first-order kinetics. The equilibrium data obtained in this study accorded excellently with the Langmuir adsorption isotherm.     

Effect of coagulation pretreatment on the fouling of ultrafiltration membrane

The purpose of this study is to understand the effect and mechanism of preventing membrane fouling, by coagulation pretreatment, in terms of fractional component and molecular weight of natural organic matter （NOM）. A relatively higher molecular weight （MW） of hydrophobic compounds was responsible for a rapid decline in the ultrafiltration flux. Coagulation could effectively remove the hydrophobic organics, resulting in the increase of flux. It was found that a lower MW of neutral hydrophilic compounds, which could remove inadequately by coagulation, was responsible for the slow declining flux. The fluxes in the filtration of coagulated water and supernatant water were compared and the results showed that a lower MW of neutral hydrophilic compounds remained in the supernatant water after coagulation could be rejected by a membrane, resulting in fouling. It was also found that the coagulated flocs could absorb neutral hydrophilic compounds effectively. Therefore, with the coagulated flocs formed on the membrane surface, the flux decline could be improved.     

Penetration analysis of elements and bioleaching treatment of spent refractory for recycling

Acidithiobacillus ferrooxidans ATCC23270 and Acidithiobacillus thiooxidans TM-32 were used for bioleaching of spent refractories of aluminium and copper melting furnaces for their recycling.Firstly,penetration of elements into aluminium melting furnace refractory was investigated and it was found that up to 7 cm from surface was contaminated.Comparison on leaching efficiency by the strains ATCC23270 and TM-32 found that the strain ATCC23270 could treat larger amount of the refractories than the strain TM-32 could do.In the experiment of bioleaching of spent refractory aluminium melting furnace by the strain ATCC23270,high leaching efficiency were obtained on Al,Si,and Ca,and extremely low leaching performance was,however,shown on the rest of elements i.e.,Na,Mn,and Zn.Under the strain TM-32 use,relatively high leaching performance was recognized on Al,Si,Ca,Na,Mn,and Zn.In the experiment of bioleaching for spent refractory copper melting furnace,almost the same leaching trends were shown on Cu,Zn,Al,and Si under the strains ACTT23270 and TM-32 uses.     

Simultaneous removal of ammonium and phosphate by zeolite synthesized from coal fly ash as influenced by acid treatment

Zeolite synthesized from fly ash （ZFA） without modification is not efficient for the purification of NH4＋ and phosphate at low concentrations that occur in real effluents, despite the high potential removal capacity. To develop an effective technique to enhance the removal efficiency of ammonium and phosphate at low concentrations, ZFA was modified with acid treatment and the simultaneous removal of ammonium and phosphate in a wide range of concentration was investigated. It was seen that when compared with untreated ZFA, only the treatment by 0.01 mol/L of H2SO4 significantly improved the removal efficiency of ammonium at low initial concentrations. The behavior was well explained by the pH effect. Treatment by more concentrated H2SO4 led to the deterioration of the ZFA structure and a decrease in the cation exchange capacity. Treatment by 0.01 mol/L H2SO4 improved the removal efficiency of phosphate by ZFA at all initial P concentrations, while the treatment by concentrated H2SO4 （≥0.9 mol/L） resulted in a limited maximum phosphate immobilization capacity （PIC）. It was concluded that through a previous mild acid treatment （e.g. 0.01 mol/L of H2SO4）, ZFA can be used in the simultaneous removal of NH4＋ and P at low concentrations simulating real effluent.