集中式饮水除砷装置的研制

为验证本专题研制的强化除砷剂的除砷效果、除砷容量以及再生效果 ,必须有中试规模的试验装置及其运行状况 ,以便推进饮水除砷剂及其除砷技术的产业化进程 ,中试基地选在源水含砷量超标的浙江省某天然泉水饮料厂 ,该集中式饮水除砷装置的处理能力为 1m3 h ,自 1999年 4月起连续运行至今 ,处理后出水符合国家生活饮用水有关卫生标准的要求 ,除砷容量高 ;成本低 ,设备管理简单 ,进水和出水均无需调节pH ;再生剂安全、价廉、效果好 ,适宜用于水砷高的农村或含砷的自备水厂     

分散式饮水除砷研究

目的：研究分散式饮水除砷技术。方法：采用混凝沉淀和涂铁砂粒吸附除砷。若源水中含有三价砷，可在混凝沉淀前将其氧化。结果：在不调pH值、人工搅拌和室温条件，如果混凝后进行砂滤，当源水五价砷含量小于0．5mg/L和为0．5－1．0、1．0－2．0mg/L时。分别投加硫酸铁20、30、60mg/L，均可使处理后出水砷含量小于0．05mg/L。若三价砷含量为1．0mg/L，按有效氯计投加2．5mg/L次氯酸钠预氧化，在相同条件下，可使三价砷的去除率与五价砷相同。用涂铁砂粒吸附三价与五价砷，均可使出水砷含量小于0．01mg/L。结论：硫酸铁、硫酸铝及其混合物是较实用的分散式饮水除砷剂，次氯酸钠为适宜的三价砷氧化剂。涂铁砂粒能有效地吸附三价与五价砷，且性能稳定。     

卫生防护与三废处理

0316 14　分散式饮水除砷研究 /罗启芳…∥环境与健康杂志 2 0 0 1,18( 6 ) 36 9～ 370研究分散式饮水除砷技术。采用混凝沉淀和涂铁砂粒吸附除砷。若源水中含有三价砷 ,可在混凝沉淀前将其氧化。结果 ,在不调pH值、人工搅拌和室温条件下 ,如果混凝后进行砂滤 ,当源水五价砷含量小于0 5mg L和为 0 5～ 1 0、1 0～ 2 0mg L时 ,分别投加硫酸铁 2 0、30、6 0mg L ,均可使处理后出水砷含量小于0 0 5mg L。若三价砷含量为 1 0mg L ,按有效氯计投加 2 5mg L次氯酸钠预氧化 ,在相同条件下 ,可使三价砷的去除率与五价砷相同。用涂铁砂粒…     

饮用水除砷技术的应用

饮用水砷含量过高可由工业性污染造成 ,也可因水文地质因素所至。据有关资料介绍 ,我国已发现 30多个地方性砷中毒流行的县。在我市某矿泉饮料厂也因源水砷含量有时超标而使水生产受到制约。为此我们开展了除砷技术的现场应用调查。一、材料和方法1 实验现场与含砷水源 :实验现场选择在某矿泉饮料厂 ,该厂是一个含锂、锶、碘和偏硅酸丰富的饮用天然矿泉水水源 ,砷含量水平波动在 0 0 3～ 0 0 7mg/L之间。2 除砷材料 :除砷材料采用骨碳和铁盐制备成的强化除砷剂及铜锌合金细粒 (KDF55) ,组成了除砷滤罐中装填的滤料。3 实验内容 :除砷效…     

负载金属饮水除砷材料的研究

目的　研究负载金属多孔材料对饮水中砷的去除效果。方法　以活性炭、活性氧化铝、硅胶、大孔树脂等多孔材料为载体 ,以铁盐、锆盐等为活化试剂制备负载金属除砷材料 ,考察材料制备条件及材料的静态和动态除砷作用。结果　选择以活性炭为载体材料、硝酸铁为活化试剂制备饮水复合除砷材料。按现行规范砷限值为 0 0 5mg L计算 ,试验的载铁活性炭材料对于三价砷浓度为 0 2 84mg L和五价砷浓度为0 2 5 4mg L模拟饮水 ,除砷容量分别可达 2 94mg g和 2 5 6mg g。结论　以活性炭和硝酸铁制备的载铁活性炭材料具有较好的饮水除砷性能     

内蒙地区水砷和人体血、尿砷含量的测定

目的：通过对内蒙地区（对照区和患病区）的水砷和人体血、尿砷含量的测定，进一步了解内蒙巴盟地区砷地方病对人体的危害及暴露水平。方法：0．5ml血样，5．0ml尿样用4＋1HNO3＋HCIO4消化，用原子荧光分光光度计测定，水样用石墨炉原子吸收法进行测定。结果：对照区人群血砷、尿砷含量的几何均值分别为1．98μg／L和11．02μg／L，病区血砷、尿砷含量的几何均值分别为16．04μg／L和135．64μg／L，病区地区人群血、尿砷明显高于对照区人群血砷、尿砷含量。对照地区水中砷含量为0．0151mg／L，病区水中砷含量为0．268mg／L，病区水砷含量明显高于对照区水砷含量。结论：本试验报告的方法灵敏度高，测定结果准确，适合对大批量样品进行流行病学调查。     

活性氧化铝吸附法饮水除砷研究

活性氧化铝的除砷机理以吸附为主,其除As~(5+)的效率非常显著地高于As~(3+)。水中As~(3+)用氯氧化后的去除率和As~(5+)相同。含砷0.75mg/L左右的原水将pH调至6.0～6.5的条件下,除砷容量为1.4～2.0mg/g Al_2O_3,处理1m3水的化学品费用为0.221元。1m~3 Al_2O_3每个周期可处理水1700m~3以上。     

饮用水除砷设备装置效果观察

砷是对人体有害的元素 ,长期饮用超标准砷的水会引起多种疾病。预防医学环境卫生与卫生工程研究所、诸暨市卫生防疫站、诸暨市天成矿泉饮料厂合作开展了现场应用研究 ,探索了饮水除砷装置 ,处理能力为 1ｍ3 /ｈ ,自1999年 4月起连续运行至今。现就饮水除砷设备装置与运行情况进行分析。材料与方法1　强化除砷剂　以骨碳为骨架材料 ,铁盐为除砷基团的供体材料制备的强化除砷剂 10 0ｋｇ,孔隙 6 0 %。堆密度ｒ1=0 6 8ｇ/ｃｍ3 ,颗粒粒径 0 3～ 2 0ｍｍ ,将除砷剂分装于 3个同样尺寸选用不锈钢或ＡＢＳ塑料制造的除砷滤罐内 ,待用。2　氧化…     

活性氧化铝吸附法饮水除砷研究

活性氧化铝的除砷机理以吸附为主,其除As~(5+)的效率非常显著地高于As~(3+).水中As~(3+)用氯氧化后的去除率和As~(5+)相同.含砷0.75mg/L左右的原水将pH调至6.0～6.5的条件下,除砷容量为1.4～2.0mg/g Al_2O_3,处理1m~3水的化学品费用为0.221元.1m~3 Al_2O_3每个周期可处理水1700m~3以上.     

浙江省农村居民饮用水中砷含量监测分析

为进一步了解浙江省地方性砷中毒分布状况 ,以便科学的制定防治措施 ,采用全省水质资料及线索调查相结合的方法 ,对 1994年桐乡市水砷含量在 0 0 5～ 0 0 7mg L的洲泉 (原青石乡 )等 8个乡镇的人群病情调查 ,发现患者 1例 ,可疑患者 2例。水砷含量 <0 0 1mg L的石门乡人群调查尚未发现可疑患者。 1998～2 0 0 2年全省检测饮用水样 2 0 0份 ,水砷含量均在 <0 0 5mg L。本次调查表明我省居民饮用水源均未发现水砷含量 >0 0 5mg L的区域。历史高砷水源的青石乡发现个别散在性地方性砷中毒患者存在 ,需作进一步远期效应的追踪研究     

活性氧化铝滤层吸附法饮水除砷现场半生产性试验研究

本文研究了现场饮水除砷及再生废水处理的工艺。用稀酸将原水pH降至6.0～6.5,再通过一个充填粒径为0.35～1.20mm、厚度为750mm的活性氧化铝滤罐。进水平均砷浓度为0.34～0.53mg/L,出水的平均砷浓度为0.014～0.028mg/L,平均除砷效率为94.7～95.9％。周期单位产水量≥4360m~3水/T·Al_2O_3。每立方米水的处理费用(包括化学品、滤料补充、废水处理)仅0.076元,低于饮水除氟的费用。强碱性含砷废水经中和及氯化铁混凝沉淀3天后,上清液中砷浓度降至0.009mg/L(远远低于0.5mg/L的排放标准),完全可以排放。     

利用电吸附技术去除水中过量砷的研究

目的 防治饮用水中过量砷对人体健康的危害，方法 利用电吸附技术（EST）去除水中过量的砷，结果 小试和现场试验结果表明，原水砷含量为0.06-0.33mg/L时，出水砷含量均低于0.01mg/L，符合国家生活饮用水卫生标准的要求。结论 电吸附技术效果稳定，操作简便，成本低于其他离子去除技术，可在高砷地区推广应用。     

对混凝沉淀法分散式饮水除砷的研究

采用混凝沉淀法进行分散式饮水除砷试验。结果表明,当水样中五价砷［Ａｓ（Ⅴ）］含量为１．０ｍ ｇ／Ｌ时,不调节ｐＨ值（ｐＨ７．８２）,直接投加５０ｍ ｇ／Ｌ硫酸铁,室温下沉淀静置１２ｈ,可使倾析液残留砷含量低于０．０５ｍ ｇ／Ｌ。如沉淀反应后静置３０～４０ ｍ ｉｎ 即过滤,则只需投加３０ｍ ｇ／Ｌ的硫酸铁或４０ｍ ｇ／Ｌ的硫酸铝即可达到同样的除砷效果。随着投加量的增加,２种混凝剂对砷的去除率均升高,当水样Ａｓ（Ⅴ）≤１．０ｍ ｇ／Ｌ和≤０．５ｍ ｇ／Ｌ时,分别投加３０ｍ ｇ／Ｌ 硫酸铁和硫酸铝,过滤后可使残留砷含量达到现行饮水卫生标准（＜０．０５ｍ ｇ／Ｌ）。在水样处于不同ｐＨ 值、水温、浊度、硬度等条件下硫酸铁的除砷性能较硫酸铝稳定。一般情况下,沉渣中的砷不会再次进入水中     

Flocculant-disinfectant point-of-use water treatment for reducing arsenic exposure in rural Bangladesh

We introduced flocculant-disinfectant water treatment for 12 weeks in 103 households in Bangladesh to assess if drinking water would be chemically and microbiologically improved and the body burden of arsenic reduced. The median concentration of arsenic in tubewell water decreased by 88% after introduction of the flocculant-disinfectant from 136 μg/l at baseline to 16 (p < 0.001). The median concentration of total urinary arsenic decreased 42% from 385 μg/g creatinine at baseline to 225 μg/g creatinine after intervention (p < 0.001). Among 206 post-intervention drinking water samples that were reportedly treated on the date the sample was collected, 99 (48%) lacked residual free chlorine and 100 (49%) were contaminated with thermotolerant coliforms. The flocculant-disinfectant markedly reduced arsenic in drinking water, but treated drinking water was frequently contaminated with fecal organisms. The lesser reduction in urinary arsenic compared to water arsenic and the health consequences of this reduction require further research.     

影响混凝沉淀除砷剂效果的若干因素及其除砷机理探讨

采用正交试验观察了混凝沉淀除砷剂成分变化、添加物以及过滤等因素对饮水除砷效果的影响 ,并探讨了混凝除砷机理。结果表明 ,硫酸铁的除砷效果优于铁铝聚合物和聚硅酸金属盐混凝剂 ;添加活性炭粉和高岭土对除砷效果无明显促进作用 ;但混凝后过滤可提高砷去除率 ,而且砂滤为适宜的过滤处理方法 ,其效果与砂的填充高度和粒径有关。经模型拟合 ,砷的吸附模式符合Langmuir吸附等温式。提示混凝过程对砷的吸附是除砷的主要机理。     

分散式饮水除砷技术的现场应用

选取山西省山阴县为实验现场 ,验证分散式饮水除砷方案。结果表明 :现场实验达到预期除砷目的 ,利用硫酸铁或硫酸铝混凝并配合砂滤可有效去除水中五价砷 ;次氯酸钠为有效的三价砷氧化剂 ;研制的涂铁砂粒 (IOCS)有良好的现场除砷性能     

饮水复合材料除砷滤芯的研制与效果评价

目的　研制饮水复合材料除砷滤芯并在高砷饮水地区进行模拟现场效果评价。方法　以载铁活性炭粉与超细聚乙烯树脂为主要成分制备复合材料除砷滤芯 ,现场使用加标高砷饮水为原水 ,测定了滤芯的安全性、除砷效果以及其它净水作用。结果　以等量载铁活性炭粉和超细聚乙烯树脂制备的复合材料除砷滤芯可安全用于饮用水处理对砷含量为 0 4mg L的实验原水 ,除砷容量可达 2 5 6mg g ,同时对水质浊度和耗氧量指标有明显改善。结论　以载铁活性炭粉与超细聚乙烯树脂为主要成分制备复合材料除砷滤芯适合于农村高砷饮水的除砷     

Evaluation of a new water treatment for point-of-use household applications to remove microorganisms and arsenic from drinking water

Contamination of drinking water by microorganisms and arsenic represents a major human health hazard in many parts of the world. An estimated 3.4 million deaths a year are attributable to waterborne diseases. Arsenic poisoning from contaminated water sources is causing a major health emergency in some countries such as Bangladesh where 35 to 77 million people are at risk. The World Health Organization (WHO) has recently recognized point-of-use water treatment as an effective means of reducing illness in developing country households. A new point-of-use water treatment system that is based on flocculation, sedimentation and disinfection was evaluated for the removal of bacterial, viral and parasitic pathogens as well as arsenic from drinking water to estimate its potential for use in developing countries. Tests were conducted with United States Environmental Protection Agency (EPA)-model and field- sample waters from developing countries. Samples were seeded with known numbers of organisms, treated with the combined flocculation/disinfection product, and assayed for survivors using standard assay techniques appropriate for the organism. Results indicated that this treatment system reduced the levels from 10(8)/l to undetectable (<1) of 14 types of representative waterborne bacterial pathogens including Salmonella typhi and Vibrio cholerae. No Escherichia coli were detected post-treatment in 320 field water samples collected from five developing countries. In addition, the water treatment system reduced polio and rotavirus titres by greater than 4-log values. Cyrptosporidium parvum and Giardia lamblia inocula were reduced by greater than 3-log values following use of this water treatment system. Arsenic, added to laboratory test waters, was reduced by 99.8%, and naturally occurring arsenic in field samples from highly contaminated Bangladeshi wells was reduced by 99.5% to mean levels of 1.2 microg/l. This water treatment system has demonstrated the potential to provide improved drinking water to households in developing countries by removing microbial and arsenic contaminants.     

A Cluster-Based Randomized Controlled Trial Promoting Community Participation in Arsenic Mitigation Efforts in Singair, Bangladesh

ABSTRACT: OBJECTIVE: To reduce arsenic (As) exposure, we evaluated the effectiveness of training community members to perform water arsenic (WAs) testing and provide As education compared to sending representatives from outside communities to conduct these tasks. METHODS: We conducted a cluster based randomized controlled trial of 20 villages in Singair, Bangladesh. Fifty eligible respondents were randomly selected in each village. In 10 villages, a community member provided As education and WAs testing. In a second set of 10 villages an outside representative performed these tasks. RESULTS: Overall, 53 % of respondents using As contaminated wells, relative to the Bangladesh As standard of 50 ?g/L, at baseline switched after receiving the intervention. Further, when there was less than 60 % arsenic contaminated wells in a village, classification used by the Bangladeshi government and UNICEF, 74 % of study households in the community tester villages, and 72 % of households in the outside tester villages reported switching to an As safe drinking water source . Switching was more common in the outside-tester (63 %) versus community-tester villages (44 %). However, after adjusting for the availability of arsenic safe drinking water sources, well switching did not differ significantly by type of As tester (Odds ratio =0.81[95 % confidence interval 0.41-1.58). At follow-up, among those using As contaminated wells who switched to safe wells, average urinary As concentrations significantly decreased. CONCLUSIONS: The overall intervention was effective in reducing As exposure provided there were As-safe drinking water sources available. However, there was not a significant difference observed in the ability of the community and outside testers to encourage study households to use As-safe water sources. The findings of this study suggest that As education and WAs testing programs provided by As testers, irrespective of their residence, could be used as an effective, low cost approach to reduce As exposure in many As-affected areas of Bangladesh.