包头市环境空气质量评价及其治理对策

文章整理了城市环境空气质量及其评价的原理和方法,并使用国内普遍采用的API空气污染指数法、模糊数学综合评判方法评价了包头市2000-2007年的环境空气质量状况变化趋势,对两种评价方法的评价结果作了对比研究,总结了不同评价方法的优缺点。结合包头市社会经济发展规划以及市区建设等因素,对当前及今后一段时期影响包头市环境空气质量的主要因素和大气污染防治的主要问题进行研究表明,包头市环境空气污染防治的主要问题是颗粒物污染影响普遍,二氧化硫排放量大,氮氧化物呈现逐渐增高趋势。以发展循环经济、建设生态市先进理念为指导,参考国内外先进经验,提出改善包头市环境空气质量的建议,主要包括调节产业结构,推行清洁生产、改善能源结构,发展循环经济、实行排污权交易、加强城市绿化建设、等措施以及必要的保障措施,以推动包头市在保持经济快速增长的同时持续改善环境空气质量。     

溧阳市1985~2011年环境空气质量变化规律的模糊综合评价

选用模糊综合评价法,对溧阳市1985~2011年环境空气质量进行了综合评价,选用SO2、NO2、TSP/PM10作为评价因素,通过计算各评价因素权重分配系数和隶属度,分析了长期空气环境质量变化趋势。结果表明:TSP/PM 10为1985年以来溧阳市首要环境空气质量制约因素,20世纪80年代中期全市空气质量主要隶属于一级标准,20世纪80年代后期主要隶属于二级标准,20世纪90年代初期主要隶属于三级标准,20世纪90年代中后期至今主要隶属于二级标准,近几年受TSP/PM1 0因素影响,在三级标准的隶属度有上升趋势;自20世纪90年代中期始,NO 2超越SO2成为继PM 10之后制约空气质量的第2大因素;经济发展对环境空气质量的规模效应较为显著,技术减排效应逐步显现。     

城市环境监测中空气质量监测途径探索

随着社会经济的快速发展,以及城市发展进程的不断深化,我国城市环境污染形势越来越严峻.现阶段,较为突出的城市环境污染问题之一就是大气污染.为了能够确保经济发展和环境质量可以实现协调发展,就需要有效地解决存在的环境污染问题,改善环境空气质量,在实际工作中不断提高环境监测水平,这对于改善城市环境空气质量、降低环境空气污染非常...     

区域环境空气质量评价体系的探讨

环境质量作为影响经济发展的重要因素,随着经济的发展,受到人们越来越多的关注;而环境质量评价是对环境质量的好坏做出定量的或半定量分析、描绘或鉴定,因此,对环境质量的综合评价极其重要,环境空气质量是环境质量中不可获缺的一部分。为了对环境空气质量状况的了解更直观,且便于区域间进行环境空气质量的横向比较,本文建立了能反映区域环境空气质量水平的评价体系,并提出了评分方法。     

基于模糊综合评价法的城市生态环境质量综合评价——以大连市为例

论文针对城市快速发展过程中的生态环境问题,在查阅大量国内外相关文献,结合实地调研的基础上,对城市生态环境现状和问题进行了分析。运用可持续发展理论和生态经济学原理,从白然、社会、经济的角度,选取了20个单项指标,构建了大连生态环境质量评价指标体系,采用专家打分法、层次分析法和模糊综合评判法构建出城市生态环境质量评价的模型。并对大连市的生态环境质量进行了实证研究,定量地对大连的生态环境进行了综合评价。通过MapInfo软件生成大连市生态环境质量空间分布图。结论为全市生态环境质量总体保持优良,中心城区、长海县生态环境质量为优,金州区、旅顺口区、瓦房店市、庄河市为良,普兰店市为中。     

环境空气质量评价法的适用性分析与比较

对几种具代表性的城市环境空气质量评价方法进行了优劣比较和适用性分析,认为在现有的综合污染指数法基础上进行改进的环境质量定性评价指数法,因其建立了与环境质量状况的关联,能够客观、科学的对环境空气质量状况进行定性评价,是一种具有比较优势的评价方法。     

绿色搜索

环保部公布2012年上半年环境质量指标 环境保护部日前公布了2012年上半年环境保护重点城市环境空气质量状况和重点流域水环境质量状况。公布的结果显示，在113个环保重点城市中，79个城市环境空气质量达到二级标准，占69．9％；33个城市空气质量超标，占29_2％。全国地表水环境质量总体为轻度污染，     

浅析上饶市环境空气质量面临的问题

大气环境是人类赖以生存和发展的必要条件,大气环境质量的好坏直接影响人们的生产生活和身体健康,随着人们生活水平的提高,空气质量状况日益成为人们关注的环保焦点之一。了解城市环境空气质量的现状,对执行大气环境质量管理工作防治城市空气环境质量的恶化有重大的意义。本文以上饶为例,根据上饶市三年环境空气质量数据,逐步分析了其空气质量污染原因,望能为上饶市环境空气质量改善工作提供一些思路和看法。     

城市生态环境质量评价方法探讨

文章采用综合指数法评价城市生态环境质量,首先确定选择评价指标的原则,然后确定评价指标及其权重,并根据评价指标的指数值计算城市生态环境质量综合指数值,再根据城市生态环境质量综合指数值确定城市生态环境的状态。     

中国城市化对环境空气质量影响的演化规律研究

运用2001-2010年237个地级以上城市的面板数据,共计2353个样本,应用计量经济学分析方法,研究城市化进程中环境空气主要污染物的演化规律.在对面板数据进行平稳性检验后,运用固定效应模型和随机效应模型,将城市空气主要污染物SO2、NO2、PM10的年平均浓度、综合污染指数4个空气质量指标与人均GDP、人口密度、第二产业结构、建成区面积4个反映城市社会经济发展的指标进行回归拟合,得到我国城市经济发展与环境质量变化的关系和演化规律,并提出政策建议.结果表明,2001-2010年,我国城市空气质量与经济发展之间的关系并不完全符合倒U型曲线,不同的污染物类型具有不同的演化规律.10年间,随着城市经济的发展,城市空气中SO2浓度呈现下降的趋势,并到达拐点,符合倒U型曲线;而对于NO2、PM10浓度及综合污染指数,10年间与经济发展之间呈U型关系,即现阶段呈现污染继续加重的态势.此外,城市第二产业结构比例、建成区面积与城市空气主要污染物浓度呈显著的正相关关系.     

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.     

Evaluation of phytoextracting cadmium and lead by sunflower, ricinus, alfalfa and mustard in hydroponic culture

Soil contaminated with heavy metals cadmium(Cd)and lead(Pb)is hard to be remediated.Phytoremediation may be a feasible method to remove toxic metals from soil,but there are few suitable plants which can hyperaccumulate metals.In this study,Cd and Pb accumulation by four plants including sunflower(Helianthus annuus L.),mustard(Brassica juncea L.),alfalfa(Medicago sativa L.), ricinus(Ricinus communis L.)in hydroponic cultures was compared.Results showed that these plants could phytocxtract heavy metals, the ability of accumulation differed with species,concentrations and categories of heavy metals.Values of BCF(bioconcentration factor)and TF(translocation factor)indicated that four species had dissimilar abilities of phytoextraction and transportation of heavy metals.Changes on the biomass of plants,pH and Eh at different treatments revealed that these four plants had distinct responses to Cd and Pb in cultures.Measurements should be taken to improve the phytoremediation of sites contaminated with heavy metals,such as pH and Eh regulations,and so forth.     

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.