黄河耗氧性有机物污染特征及泥沙对其参数测定的影响

对黄河干流1980,1992～1999年耗氧性有机物污染监测数据进行了分析,并通过对高锰酸盐指数(CODMn)与泥沙含量监测数据间的相关分析和模拟实验研究,探讨了泥沙对CODMn测定的影响.结果表明:(1)由于泥沙中腐殖质的成分之一富里酸能溶解于酸,在水样加酸处理过程中将进入水相,且富里酸能被化学氧化剂所氧化,但在自然条件下很难发生生物氧化和消耗水体的溶解氧,因此,由于泥沙的影响,CODMn夸大了耗氧性有机物的污染;(2)黄河干流河水的生化需氧量(BOD5)从上游至下游存在增加的趋势;(3)1992年干流河水的BOD5显著大于1980年的BOD5,在1992～1999年间,河水BOD5的年均值存在上升的趋势,枯水期均值存在上升的趋势,而丰水期均值的增长趋势不明显,由此表明,耗氧性有机污染物的点源排放在增加,而面源排放的增长趋势不明显,甚至存在降低的趋势;(4)黄河干流的耗氧性有机污染物主要来自点源排放,BOD5的点源与面源负荷的多年均值之比为2 81.     

穿城河流邕江水质主成分特征分析研究

采用多元统计主成分分析方法对城市河流邕江8个监测断面的高锰酸盐指数、化学需氧量、生物需氧量、溶解氧等10个水质指标进行分析计算.结果表明:(1)提取占总方差86.99％的3个因子来反映邕江水体的污染程度:①以氨氮、高锰酸指数、总磷、溶解氧、石油类、化学需氧量等有机污染因子控制;②粪大肠菌群和酸碱性控制;③重金属也存在于邕江.(2)上游水质明显优于下游,表明城区产生的工业与生活污水对邕江水质产生了明显影响.     

潭江整治—阶段胜利,继续攻坚

<正>一条潭江,自西向东;一个断面,牵动人心。根据国家发布的考核断面监测数据,今年2月份,潭江牛湾断面水质为Ⅳ类,超标项目为溶解氧。目前牛湾断面水质仍不能稳定在Ⅲ类,要想2020年达到Ⅱ类水质目标任务艰巨。记者了解到,截至2019年,江门全市在潭江流域共设置河长制监测断面64个,其中潭江干流设置断面3个(不含国考、省考5个断面)、潭江跨县支流设置断     

全有机碳(TOC)与全需氧量(TOD)

TOC及TOD都是水中需氧污染质的综合指标。由于目前应用的五天生化需氧量(nOD0指标,测试时间长,不能快速反应环境水被需氧污染质污染的程度,国外很多试验室都在进行TOC及TOD的试验,寻求它们与BOD5的关系,以便实现自动快速测定。水体受无机还原物及有机需氧污染质污染时,都要消耗水中的溶解氧。当耗氧速度大于复氧速度时,溶解氧逐渐减少直至于零,此时     

华北稳定塘氧平衡的研究

溶解氧(DO)是氧化塘内有机物降解的主要动力,本文介绍了华北稳定塘中的妤氧塘和强化塘进行污水妤氧处理所需氧的来源主要是浮游藻类光合放氧。在春季和秋季藻类产的氧可占水体溶解氧总来源的80％左右,氧的消耗是以“水呼吸”耗氧为主,“泥呼吸”耗氧为次。从氧平衡的角度阐述了各塘有机物降解与藻类产氧、生物耗氧的关系。      

水质标识指数法在鉴江流域水质评价中的应用研究

通过单因子水质标识指数法和综合水质标识指数法,以2008年-2015年茂名市4条主要干支流的监测数据为基础,选取溶解氧、高锰酸盐指数、五日生化需氧量、氨氮和总磷为监测对象,对同一条河流不同断面及同一时段不同河流的水质监测数据进行分析,评价河流综合水质的污染情况及功能区达标情况,并对鉴江、罗江、袂花江和小东江的综合水质随时间变化进行了定量评价.结果表明,2015年鉴江上游与下游单元对干流的污染贡献最大,中游单元的污染程度最小,由中游至下游污染程度逐渐加重,即鉴江的污染主要来自下游;支流中小东江污染程度最高,袂花江与罗江的水体相对较好.2008年-2015年期间鉴江、罗江、袂花江、小东江的年综合水质变化呈现出不同程度的改善、恶化,其综合水质曲线呈波浪式并在一个水质类别之间上下浮动,综合水质均达到水功能区水质目标要求.     

海浪河水污染特征分析研究

海浪河作为牡丹江的一级支流,多年来一直是被高度重视水质的保护工作.采用2014年海浪河3个监测断面的水质数据,分析了海浪河的水污染特征,研究结果表明:(1)海浪河干流3个监测断面中有10项指标未检出;汞、锌、硒、硫化物仅在部分断面有检出;高锰酸盐指数、氨氮和氟化物3项指标在各个断面不同水期均有检出;(2)海浪河沿程变化特征为上游至下游水质逐渐变差,但变化幅度较小;水期变化特征为整体呈现丰水期＞平水期＞枯水期,面源污染特征明显;(3)海浪河不同水期各断面污染物年平均值的单因子污染指数均小于1,表明海浪河水体中污染物浓度均满足Ⅱ类和Ⅲ类水质标准.     

海河流域河流耗氧污染变化趋势及氧亏分布研究

耗氧污染是海河流域河流水污染的主要类型,耗氧污染物对河流溶氧的消耗产生的氧亏效应对水生生物产生重大影响.收集海河流域重点水功能区88个监测站点2000—2011年CODCr/CODMn、NH3-N指标,分析河流耗氧污染特征及演变趋势,并基于水质目标(2 mg·L-1)下计算出海河流域河流氧亏量.结果表明,流域河流耗氧污染总体呈现好转趋势,耗氧污染指标(NH3-N、CODCr/CODMn)逐渐降低,I~III类水质站点比例增加,劣V类水质站点数和超标倍数减少;CODMn降低幅度大于NH3-N,主要污染物由COD向NH3-N转化.海河流域重点氧亏区域主要集中于中部平原段和下游滨海段,未氧亏区域多集中于上游山区段;北三河、黑龙港运东与徒骇马颊河水系中部平原段整体处于缺氧区域,子牙河水系中部平原区缺氧现象最为严重,氧亏区域位于石家庄洨河下游、滏阳河艾辛庄下游至献县段及石津总干以南;海河流域内中部平原段河流氧亏的主要贡献仍以COD为主,但氨氮的贡献显著,其中黑龙港运东水系、徒骇马颊河水系和北三河水系,COD耗氧均值都高于5 mg·L-1,在北三河和子牙河水系,氨氮耗氧均值达到了4 mg·L-1.     

大汶河水质状况评价和污染源分析

河流水质评价和污染源分析对河流污染治理和有效管理具有重要的意义。基于2019年6月(枯水期)和8月(丰水期)大汶河干流和主要支流21个监测断面16项水质指标的检测数据,综合运用单因子污染指数法、内梅罗污染指数法和因子分析法对大汶河流域水质状况和污染来源进行了评价与分析。结果表明:大汶河流域水体整体水质较差,以Ⅴ类水为主,21个断面枯水期Ⅴ类水质断面占比为66.7%,丰水期Ⅴ类水质断面占比为81%;枯水期大汶河水质明显优于丰水期,且从大汶河上游至下游其水质污染程度逐渐加重;大汶河流域水体中主要污染物为TN、NH~+_4-N、Hg和Se等,属有机污染和重金属污染类型,污染物主要来源于流域耕地面源性污染和冶金、化工、纺织等工业企业工业废水的排放。该研究结果可为大汶河流域水体污染治理提供依据。     

沙颍河流域污染控制因素及水体重金属迁移规律研究

基于沙颍河流域的水环境污染研究,利用不同污染评价指数的计算方法,针对不同水期、不同干流、不同支流河段水体样本的重金属污染特征进行分析,对沙颍河流域水环境污染控制因素及迁移影响规律进行探究,旨在为沙颍河流域水环境污染防治提出具有针对性的理论依据。结果表明：沙颍河流域整体在枯水期存在轻度Mn、Mo污染现象,流域整体污染受控于上游支流颍河和支流北汝河的污染,其中支流颍河污染的主要控制因素为Mn,支流北汝河污染的主要控制因素为Mn和Mo。污染的主要来源为矿产和工业污废水的排放,自上游至下游河段顺水流迁移转化,而流域整体呈轻度污染,污染水平主要受到pH值、溶解氧(DO)、温度(T)的影响。     

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.