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1.
随着生活水平的不断提高,人们对饮用水质量提出了更高的要求,而水环境质量的普通恶化又使人们不得不考虑饮用水的安全性。在简介了我国水资源现状的基础上,文中阐述了水质问题的重要性和我国水体环境质量的严峻性,指出了水质问题不仅制约着社会经济的发展,更直接地丰人们饮用水的安全性,已成为进入21世纪我国水资源问题的主要矛盾;在分析了我国水资源水质管理存在问题的基础上,从法律、法规、政策、经济等方面,着重探讨了加强水质管理与解决水资源供需矛盾和保证饮用水安全的关系。  相似文献   

2.
UV/peroxymonosulfate (UV/PMS) advanced oxidation process has attracted significant attention for removal of micropollutants in water. However, during practical water treatment applications, the PMS treatment must be performed before the UV treatment to achieve full contact. In this study, sulfamethoxazole (SMX) was selected as the target micropollutant. Four different operational approaches, including UV alone, PMS alone, simultaneous UV/PMS and sequential PMS-UV, were compared for their differences in SMX removal and disinfection by-product (DBP) formation potentials during chlorine-driven disinfection. Among the four approaches, UV/PMS and PMS-UV achieved over 90% removal efficiencies for SMX without substantial differences. For raw water, the trichloronitromethane (TCNM) formation potential after treatment with PMS-UV was lower than that after UV/PMS treatment. The time interval over which the PMS-UV process was conducted had little effect on the final removal efficiency for SMX. However, a brief (5 min) pre-PMS treatment significantly reduced the TCNM formation potential and the genotoxicity from DBPs. The formation risk for TCNM during chlorination increased markedly with increasing PMS dosages, and the appropriate dosage under these experimental conditions was suggested to be 0.5–1.0 mmol/L. Under alkaline conditions, PMS-UV treatment can enhance SMX degradation as well as dramatically reduced the formation potentials for haloketones, haloacetonitriles and halonitromethanes. This study suggests that proper optimization of UV/PMS processes can remove SMX and reduce its DBP formation.  相似文献   

3.
人工浮岛对城市景观用水水质净化效果的研究   总被引:1,自引:0,他引:1  
为了研究浮岛对城市景观用水的水质净化效果,用美人蕉制作了人工浮岛,分别在大连市某小区户外水塘和实验室内进行了实验。对其水样进行化验、观察、分析和研究。结果表明:人工植物浮岛对水质净化有明显的效果,在室内对总氮、总磷和COD的去除率分别为91.35%、45.46%和56.49%;在户外对总氮、总磷和COD的去除率分别为60%、84.33%和24.25%。实验证明了人工浮岛在城市景观用水处理中有广阔的应用前景。  相似文献   

4.
人工富集微生物技术对太湖梅梁湾水源地氮磷的去除研究   总被引:3,自引:0,他引:3  
詹旭 《环境科技》2006,19(6):1-2
采用2种载体(PM和ACP)进行人工富集微生物的方法,来去除太湖梅梁湾水源地水中的氮磷污染物。通过研究不同的载体密度和水力停留时间对去除效率的影响,中试结果表明:当载体密度为13.1%,停留时间为7d,源水中ρ(TN)为2.95~6.41mg·L-1,ρ(NH4 -N)为0.49~3.31mg·L-1,ρ(NO2--N)为0.07~0.51mg·L-1,ρ(TP)为0.084 ̄0.25mg·L-1,ρ(PO4--P)为0.005~0.059mg·L-1的条件下,人工富集微生物技术对TN,NH4 -N,NO2--N,TP,PO4--P的平均去除率最高分别达到22.68%,57.08%,88.83%,45.36%,29.58%,可见利用人工富集微生物技术能有效去除水源地中的氮磷营养盐,对富营养化水源地水体的水质有明显的改善作用。  相似文献   

5.
基于GIS的凤嘴江水污染控制规划数据库研究   总被引:1,自引:0,他引:1  
何强  翟俊 《重庆环境科学》2001,23(3):29-32,37
地理信息系统(GIS)是20世纪60年代兴起的新技术,将它应用于水污染控制规划(WPCP)是一个新的研究领域,其中数据库是整个系统的基础和信息源,也是系统发展的瓶颈技术之一,有必要进行深入和全面的研究,由于水污染控制规划系统本身的复杂性,决定了其所涉及的数据比一般的管理信息系统得杂得多,本研究以GeoMediaProfessional3.0为基础平台,对系统数据库建库过程中涉及的数据特点,数据结果与数据模型,数据组织与管理,数据库功能分析等问题进行了研究,开发了GIS技术的凤嘴江水污染控制规划数据库,较好地满足了GIS应用的要求,为相关数据库的建设提供了经验。  相似文献   

6.
堆肥式生态厕所处理人类排泄物变化规律研究   总被引:2,自引:0,他引:2  
选用秸秆和木屑的混合物作为生态厕所反应基质,采用日本研制生产的s-15型生态厕所为实验装置,通过好氧微生物的氧化分解,将粪便转化为无臭味的水、二氧化碳和较干燥的有机肥.实验模拟实际生活,通过5~6人正常使用方式投加物料,旨在研究生态厕所在现实生活中处理人类排泄物的变化规律.通过分析实验过程中的物料投加量、使用周期、温度、含水率等指标的变化.发现生态厕所使用的第5~12周,温度在50℃左右,含水率稳定在50%~60%之间时生态厕所减量化效果最为理想.  相似文献   

7.
本文运用系统动力学原理,构建了徐州市水资源承载力系统SD模型。并利用该模型,研究徐州市水资源承载力在不同发展方案下的变化趋势。最终得出开源、节流、治污并举的综合方案是徐州市水资源可持续发展利用的最优方案,同时指出开源措施对徐州市水资源承载力提高效果最为明显。并有针对性的提出提高徐州水资源承载力的建议与措施。  相似文献   

8.
The inevitable release of engineered silver nanoparticles (AgNPs) into aquatic environments has drawn great concerns about its environmental toxicity and safety. Although aggregation and transformation play crucial roles in the transport and toxicity of AgNPs, how the water chemistry of environmental waters influences the aggregation and transformation of engineered AgNPs is still not well understood. In this study, the aggregation of polyvinylpyrrolidone (PVP) coated AgNPs was investigated in eight typical environmental water samples (with different ionic strengths, hardness, and dissolved organic matter (DOM) concentrations) by using UV–visible spectroscopy and dynamic light scattering. Raman spectroscopy was applied to probe the interaction of DOM with the surface of AgNPs. Further, the photo-transformation and morphology changes of AgNPs in environmental waters were studied by UV–visible spectroscopy, inductively coupled plasma mass spectrometry, and transmission electron microscopy. The results suggested that both electrolytes (especially Ca2 + and Mg2 +) and DOM in the surface waters are key parameters for AgNP aggregation, and sunlight could accelerate the morphology change, aggregation, and further sedimentation of AgNPs. This water chemistry controlled aggregation and photo-transformation should have significant environmental impacts on the transport and toxicity of AgNPs in the aquatic environments.  相似文献   

9.
IntroductionInordertoalleviateseverewatershortagesinnorthChina ,ChinesecentralgovernmenthavestartedtoimplementtheSouth NorthWaterTransferScheme(SNWT) ,whichwilltransferwaterfromYangtzeRiverbasininthesouthtoHuang Huai Hai(YellowRiver ,HuaiheRiverandHaiheRi…  相似文献   

10.
This paper assess the eco-environmental benefits that may come from the middle route project of China‘s South-North Water Transfer Scheme(SNWT) with principles and methods of eco-economics and planning reports of SNWT‘s middle route project. Some benefits were calculated in monetary units. To make sure that the results can be comparable with normal monetary indices, concrete assessment objects and the parameters are prudently selected according to the major characteristics of the project and its water import region. Primary assessment revealed that in different project construction stages, the benefit could be more than 13.07 billion RMB Yuan in 2010 and 19.79 billion RMB Yuan in 2030, respectively. The monetary value tends to increase with social-economic development. To realize these potential benefits, however, calls for more endeavors.  相似文献   

11.
通过在镉含量高、低不同的2种土壤上的自制根箱试验并对所种植作物的镉含量进行相关性分析,研究了两种蕹菜镉积累典型品种,强坤柳叶白骨(QK,Cd-PSC)和台湾308纯白柳叶(T-308,非Cd-PSC)的根际土壤酶区系.结果表明:品种间茎叶镉含量差异极显著;在高镉条件下,蕹菜茎叶Cd含量与根际转化酶活性呈显著正相关;在低镉条件下,与根际碱性磷酸酶活性呈显著负相关.  相似文献   

12.
基于2019年8月与11月所获取的2个航次的水文、化学和生物资料,重点研究了夏、秋季南黄海和长江口海域溶解氧(DO)分布的时空格局及其与水文动力状况和生物地球化学过程之间的关系,探讨了该海区低氧特征及其对酸化环境的指示.结果表明,研究海域内DO含量及分布与流场/水团格局具有良好的对应关系,其中夏季长江口外台湾暖流影响区具有低氧的特征,秋季则在黄海冷水团海域下底层存在一个DO低值区.在上升流影响下,夏季长江口海域的底层低氧水体可抬升至上层水体,低氧水体由长江口海域向东北方向扩展;夏季长江口外下层低氧水体的涌升、黄海冷水团区DO最大值层的抬升均与跃层的抬升趋势基本一致,不仅反应了上升流对DO垂向分布的影响,同时也指示了冷水团边界区和长江口外海域涌升流的存在.此外,夏季长江口外东北部离岸低盐水团区的生物地球化学过程也对局地底层低氧区的形成有重要贡献.在夏季的长江口海域和秋季的黄海冷水团海域存在水体酸化区,其中长江口的酸化区范围与低氧区总体相吻合,秋季黄海冷水团底层酸化区也与DO低值区和冷水团范围基本一致.本研究结果可为南黄海和长江口海域低氧和酸化等生态环境问题的改善提供理论指导.  相似文献   

13.
采用自动固相萃取-气质联用法分析饮用水源中的甲基汞,通过巯基棉小柱萃取大体积(5L)水样后,选择离子扫描方式(SIM)进行定量。实验对比国家标准方法具有更好的线性关系,实际操作简单快捷,灵敏度高。3个浓度水平进行加标回收实验,回收率分别大于71.0%、74.4%、76.0%。对10μg/L浓度重复进样6次,相对标准偏差(RSD)为4.8%。该方法检出限可达到3×10-4μg/L,满足饮用水源水中甲基汞标准限值要求。  相似文献   

14.
Efficiency assessment of water and sewerage companies (WaSCs) has attracted considerable attention both for water company managers and water regulators. Within the methodological approaches that can be applied to estimate efficiency scores, data envelopment analysis (DEA) is the most widely applied technique. In spite of the positive features of DEA, it presents a major drawback which is its deterministic nature. In other words, conventional DEA models do not account for uncertainty in the data. To overcome this limitation, we assess, for the first time, the efficiency of a sample of Chilean WaSCs by using a DEA model with statistical tolerance in the data. Hence, 81 efficiency scores are estimated for each WaSC rather than a single score as with conventional DEA models. The results illustrate that outputs exhibit larger uncertainty than inputs. Moreover, WaSCs efficiency scores change significantly under the best-case and worst-case scenarios. The ranking of the WaSCs allows for the identification of which of them has the highest performance based on their efficiency scores. This information is essential to enhance efficiency and innovation in the water industry. Moreover, the introduction of uncertainty in the efficiency assessment allows for the prediction and ranking of future performance of WaSCs.  相似文献   

15.
Pot and field experiments were conducted to investigate the effects of water regimes on the speciation and accumulation of arsenic (As) and cadmium (Cd) in Brazilian upland rice growing in soils polluted with both As and Cd. In the pot experiment constant and intermittent flooding treatments gave 3-16 times higher As concentrations in soil solution than did aerobic conditions but Cd showed the opposite trend. Compared to arsenate, there were more marked changes in the arsenite concentrations in the soil solution as water management shifted, and therefore arsenite concentrations dominated the As speciation and bioavailability in the soil. In the field experiment As concentrations in the rice grains increased from0.14 to 0.21 mg/kg while Cd concentrations decreased from 0.21 to 0.02 mg/kg with increasing irrigation ranging from aerobic to constantly flooding conditions. Among the various water regimes the conventional irrigation treatment produced the highest rice grain yield of 6.29 tons/ha. The As speciation analysis reveals that the accumulation of dimethylarsinic acid (from 11.3% to 61.7%) made a greater contribution to the increase in total As in brown rice in the intermittent and constant flooding treatments compared to the intermittent-aerobic treatment. Thus, water management exerted opposite effects on Cd and As speciation and bioavailability in the soil and consequently on their accumulation in the upland rice. Special care is required when irrigation regime methods are employed to mitigate the accumulation of metal(loid)s in the grain of rice grown in soils polluted with both As and Cd.  相似文献   

16.
为评价黄河干流中卫新墩断面近年水质状况及水质变化趋势,文章采用综合污染指数法对新墩断面2004年以来的水质状况进行了分析。结果表明:新墩断面水质达到功能区水质要求,受到轻微污染,水质一般。在此基础上,文章利用GM(1,1)模型,借助Matlab软件,拟合了新墩断面未来水质污染变化方程,得出了新墩断面未来水质将进一步好转的结论。  相似文献   

17.
曹力媛 《环境科学研究》2017,30(10):1524-1532
为分析太原市采暖期和非采暖期PM2.5的特征,利用单颗粒气溶胶质谱仪(SPAMS)分析太原市典型生活区采暖期(2016年3月11-18日)和非采暖期(2016年4月1-7日)PM2.5的来源及组成.结果表明:① 采暖期(停暖前)颗粒物有机碳、硫酸盐和多环芳烃等信号强度大于非采暖期(停暖后),而元素碳、硝酸盐、铵盐等反之.② 为了尽可能排除气象因素的影响,选取风向(东南风)、风级(二级)相同时段的颗粒物进行分析,停暖前后颗粒物主要化学组分为有机碳、混合碳和元素碳,采暖前有机碳占比(达51.9%)最高,非采暖期元素碳占比(32.6%)最高.采暖期有机碳、高分子有机物和左旋葡聚糖占比明显高于非采暖期,元素碳、矿物质和重金属反之.③ 停暖前后首要的两类污染源为燃煤和机动车尾气,二者贡献率之和分别高达70.1%和67.4%,可见本地主要受这两类源的影响.燃煤在采暖期为首要污染源,并且贡献比例高于非采暖期,而机动车尾气在非采暖期为首要污染源,且比例明显高于采暖期.研究显示,采暖和非采暖期虽然首要污染源有所差异,但在污染过程中,机动车尾气源的贡献比例均高于优良时段,说明无论是采暖期还是非采暖期,除燃煤排放的影响外,机动车尾气的影响也需得到重视,建议加强机动车燃油品质的升级,使用清洁煤,并在重污染时段采取相应的管控措施.   相似文献   

18.
UV/chlorine process, as an emerging advanced oxidation process (AOP), was effective for removing micro-pollutants via various reactive radicals, but it also led to the changes of natural organic matter (NOM) and formation of disinfection byproducts (DBPs). By using negative ion electrospray ionization coupled with Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS), the transformation of Suwannee River NOM (SRNOM) and the formation of chlorinated DBPs (Cl-DBPs) in the UV/chlorine AOP and subsequent post-chlorination were tracked and compared with dark chlorination. In comparison to dark chlorination, the involvement of ClO?, Cl?, and HO? in the UV/chlorine AOP promoted the transformation of NOM by removing the compounds owning higher aromaticity (AImod) value and DBE (double-bond equivalence)/C ratio and causing the decrease in the proportion of aromatic compounds. Meanwhile, more compounds which contained only C, H, O, N atoms (CHON) were observed after the UV/chlorine AOP compared with dark chlorination via photolysis of organic chloramines or radical reactions. A total of 833 compounds contained C, H, O, Cl atoms (CHOCl) were observed after the UV/chlorine AOP, higher than 789 CHOCl compounds in dark chlorination, and one-chlorine-containing components were the dominant species. The different products from chlorine substitution reactions (SR) and addition reactions (AR) suggested that SR often occurred in the precursors owning higher H/C ratio and AR often occurred in the precursors owning higher aromaticity. Post-chlorination further caused the cleavages of NOM structures into small molecular weight compounds, removed CHON compounds and enhanced the formation of Cl-DBPs. The results provide information about NOM transformation and Cl-DBPs formation at molecular levels in the UV/chlorine AOP.  相似文献   

19.
A study on the removal of Co(Ⅱ) from aqueous solutions by water treatment residuals(WTR)was conducted in batch conditions. The sorption process of Co(Ⅱ) followed pseudosecondorder kinetics, with 30 hr required to reach equilibrium. Using the Langmuir adsorption isotherm model, a relatively high maximum sorption capacity of 17.31 mg/g Co(Ⅱ) was determined. The adsorption of Co(Ⅱ) was dependent on pH values and was affected by the ionic strength. Results show that Co(Ⅱ) adsorption was a spontaneous endothermic process and was favorable at high temperature. Most of the adsorbed Co(Ⅱ) stayed on the WTR permanently, whereas only small amounts of adsorbed Co(Ⅱ) were desorbed. The shifting of peaks in FT-IR spectra indicated that Co(Ⅱ) interacted with the WTR surface through strong covalent bond formation with Fe(Al)–O functional groups. It was concluded that WTR can be a suitable material from which to develop an efficient adsorbent for the removal of Co(Ⅱ) from wastewater.  相似文献   

20.
主要讨论了水质自动监测站在建立与运行中应注意的一些问题。从取样点的选址、仪器设备的购置与安装、人员培训、系统验收到自动监测系统的运行管理和质量控制等方面,提出了一些自己的看法。  相似文献   

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