首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 171 毫秒
1.
合成洗涤剂     
小曾 《环境教育》2000,(3):38-39
资料洗涤剂的作用与危害 合成洗涤剂的产量现在已经超过肥皂产量,我国合成洗涤剂的主要成份是烷基苯硫酸钠,占洗涤剂总产量的90%。合成洗涤剂易溶于水,随着洗衣机的广泛使用,用量越来越大。但是洗涤剂属于表面活性物质,是一种有机物,在光热条件下易氧化分解,大量消耗水中的溶解氧,致使水中的鱼和贝类等生物因缺氧而不能正常生长,甚至死亡。此外,洗涤剂的表面活性作用还会使水中的有毒有机物的溶解度增加,废水毒性增强,威胁生物的生存,也会污染地下水质,最终危害人体的健康。 最引人注意的一点是:洗涤剂是造成水体富营养化…  相似文献   

2.
饮用水中砷去除技术综述   总被引:2,自引:0,他引:2  
李莉  王业耀  孟凡生 《四川环境》2008,27(1):87-90,101
自从1996年孟加拉国和印度报道慢性砷中毒事件以来,饮用水砷污染和砷中毒问题就受到全世界的关注。如何解决这一难题,研究人员进行了大量研究。本文综述了饮用水中砷的去除方法,包括混凝/沉淀、吸附、离子交换技术等,对各种除砷技术进行了总结和比较。  相似文献   

3.
水体中氟乐灵的生物毒性和去除研究进展   总被引:2,自引:0,他引:2  
作为一种在全球范围内广泛使用的二硝基苯胺类除草剂,氟乐灵对环境和人体健康的潜在危害越来越受到人们的关注.本文首次总结了水体中氟乐灵的来源、生物毒性、毒性机理以及饮用水处理中去除氟乐灵的物理、化学和生物方法.传统单独的加氯消毒、生物膜工艺等通常难以高效去除水体中的氟乐灵,而以紫外线和臭氧为基础的高级氧化技术(AOPs)由于能产生具有强氧化能力的羟基自由基而对水体中痕量氟乐灵有较好的去除效果.最后在此基础上,对今后的研究方向进行了展望,提出改进饮用水中微量氟乐灵的毒性检测和去除工艺亟待解决的问题.  相似文献   

4.
美利用微生物去除饮用水中硝酸盐UtilizationofMicrobeforRemovalofNitratesinDrinkingWater受化肥及其它有害物污染的饮用水中,均含有效高浓度的硝酸盐,据研究显示,该物质能诱发人类罹患癌症。到目前为止,尚...  相似文献   

5.
饮用水原水微污染及其处理技术   总被引:6,自引:1,他引:5  
于鑫  李旭东 《四川环境》1998,17(1):24-30
水环境污染造成的饮用水原水水质下降及传统给水处理工艺的缺陷导致饮用水中含有THMs,MX等(可疑)致癌物及其它有机物,严重威胁人体健康。水处理工作者对传统工艺进行了诸多改进,并开发了种类繁多的新型物理、化学技术及生物预处理技术。本文对三者进行了系统的总结,并重点分析了后者,认为:生物预处理技术在成本上能够为我国大部分地区所接受,毒理学安全,见效快,它与改进后的传统工艺的联用应成为国内水厂改善出水水质的首选方法。  相似文献   

6.
在沱江干流区域采集了29个地表水样品,分析了高氯酸盐浓度水平,评估了居民通过饮用水造成的高氯酸盐暴露情况。研究表明,高氯酸盐广泛存在于沱江干流河水中,浓度为3.39~19.60μg/L。高氯酸盐含量在沱江干流区域有一定空间分布特征,人口和工业相对集中的成都和资阳段地表水中高氯酸盐浓度更高。人体暴露评估结果表明,在平均暴露模式下,沱江干流区域居民通过饮用水暴露于高氯酸盐的量未超过美国环保署规定,基本安全。  相似文献   

7.
如何有效去除水中高氯酸盐,解决普通零价铁去除效果不佳和易被氧化等缺点是本研究的主要出发点。采用浸润法制备活性炭负载纳米零价铁复合材料,运用扫描电镜对复合材料进行表征,考察了不同条件下复合材料对高氯酸盐的去除效果,并分析了去除机理。研究结果表明:高氯酸盐去除效果在一定范围内随着材料含铁量的增加而升高;高氯酸盐去除效果与其初始浓度呈负相关;pH=5时,去除效果最好;共存阴离子对去除效果具有一定抑制作用;溶液中高氯酸根最终被复合材料(nZVI-GAC)还原成无毒Cl-。  相似文献   

8.
巢湖水中邻苯二甲酸酯安全性评价   总被引:1,自引:0,他引:1  
本文测定了5种PAEs在巢湖水中的质量浓度,邻苯二甲酸二甲酯、邻苯二甲酸二乙酯、邻苯二甲酸二丁酯和邻苯二甲酸二异辛酯在所有采样点位均有检出,邻苯二甲酸二甲酯的最高质量浓度为3.15μg/L、邻苯二甲酸二乙酯的最高质量浓度为1.82μg/L、邻苯二甲酸二丁酯的最高质量浓度为12.95μg/L,邻苯二甲酸二异辛酯最高为7.21μg/L,未检出邻苯二甲酸二正辛酯。运用数学模型对PAEs在水中的环境行为进行了安全性评价,结果显示巢湖水受到邻苯二酸酯不同程度的污染。  相似文献   

9.
饮用水生物稳定性评价指标研究进展   总被引:1,自引:0,他引:1  
池年平  董秉直  何夏清 《四川环境》2010,29(1):106-109,114
保障管网中生物稳定性是饮用水安全保障的重点,本文概述了饮用水中生物稳定性评价指标的研究进展,对比分析了国内外不同生物稳定性评价指标及其各优缺点,并提出了今后研究的重点和方向。  相似文献   

10.
硫化物测定中的几个问题黄永生(中原油田技术监测中心)水中硫化物会对环境造成污染,当其含量超过排放标准(GB897-88中规定硫低于2.0mg/L)数百倍时,能使动植物体中毒,甚至导致死亡。用碘量法测硫化物含量的方法在许多书中都有记载,但是大多没有对细...  相似文献   

11.
Perchlorate, an anion that originates as a contaminant in ground and surface waters, is both naturally occurring and manmade. Because of its toxicity, there has been increased interest in setting drinking water safety standards and in health effects when perchlorate is present at low (parts per billion (ppb)) levels. In January 2009, the EPA issued a heath advisory to assist state and local officials in addressing local contamination of perchlorate in drinking water. The interim health advisory level of 15 micrograms per liter (μg/L), or ppb, is based on the reference dose recommended by the National Research Council (NRC) of the National Academy of Sciences (NAS). This paper describes scope and extent of contaminant issues and a legal process of setting standards for perchlorate concentration in drinking water in the United States of America.  相似文献   

12.
Within Canada, it has been recognized in the last decade that military training activities may have impacts on the environmental quality of training ranges. However, impacts of activities specific to Air Force Bases have not yet been intensely documented. A hydrogeological study was accomplished at the Cold Lake Air Weapons Range, Alberta, to evaluate the environmental impacts of using bombs, rockets, strafing, and open burning/open detonation (OB/OD) on the quality of soil, ground water, surface water, and lake sediments. Samples were analyzed for metals, anions, ammonium perchlorate (NH(4)ClO(4)), and energetic materials (EM). It was found that training activities did not result in measured values being exceeded on the basis of guidance values for surface water and lake sediments. Contamination by metals was mostly limited to soils, and some metals may be related to the use of bombs (Cd, Cu, Pb), strafe (Cu), and rockets (As, Ba, Cd, Cr, Cu, Fe, Ni, Pb, U, V, Zn). TNT (2,4,6-trinitrotoluene) was the main EM found in soils, while RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) was more common in ground water. Both are related to live bombing, while nitroglycerine (NG) is related to rocket use and was detected in soils only. Aluminum, nitrate, and ammonium perchlorate detected in ground water may be related to live bombing or rockets. OB/OD operations resulted in the presence of various EM in soils, and of perchlorate and nitrate in ground water. Contamination by metals and explosives in soils was localized around the targets and varied significantly in time; however, in ground water it was more constant and may persist for a period of several years after a target has been removed.  相似文献   

13.
Perchlorate (ClO4-) contamination of ground water and surface water is a widespread problem, particularly in the western United States. This study examined the effect of biodegradation on perchlorate fate and transport in soils. Solute transport experiments were conducted on two surface soils. Pulses of solution containing perchlorate and Br- were applied to saturated soil columns at steady state water flow. Perchlorate behaved like a nonreactive tracer in Columbia loam (coarse-loamy, mixed, superactive, nonacid, thermic Oxyaquic Xerofluvent) but was degraded in Yolo loam (fine-silty, mixed, superactive, nonacid, thermic Mollic Xerofluvent). Batch experiments demonstrated that perchlorate removal from solution in Yolo loam was caused by biodegradation. Other batch experiments with Yolo loam surface and subsurface soils, Columbia loam surface soil, and dredge tailings demonstrated that perchlorate biodegradation required anaerobic conditions, an adequate carbon source, and an active perchlorate-degrading microbial population. The sequential reduction of perchlorate and NO3- by an indigenous soil microbial community in Yolo loam batch systems was also studied. Nitrate reduction occurred much sooner than perchlorate reduction in soils that had not been previously exposed to perchlorate, but NO3- and perchlorate were simultaneously reduced in soils previously exposed to perchlorate. The results of this study have implications for in situ remediation schemes and for agricultural soils that have been contaminated by perchlorate-tainted irrigation water.  相似文献   

14.
Dyes are an important class of pollutants, and can even be identified by the human eye. Disposal of dyes in precious water resources must be avoided, however, and for that various treatment technologies are in use. Among various methods adsorption occupies a prominent place in dye removal. The growing demand for efficient and low-cost treatment methods and the importance of adsorption has given rise to low-cost alternative adsorbents (LCAs). This review highlights and provides an overview of these LCAs comprising natural, industrial as well as synthetic materials/wastes and their application for dyes removal. In addition, various other methods used for dye removal from water and wastewater are also complied in brief. From a comprehensive literature review, it was found that some LCAs, in addition to having wide availability, have fast kinetics and appreciable adsorption capacities too. Advantages and disadvantages of adsorbents, favourable conditions for particular adsorbate–adsorbent systems, and adsorption capacities of various low-cost adsorbents and commercial activated carbons as available in the literature are presented. Conclusions have been drawn from the literature reviewed, and suggestions for future research are proposed.  相似文献   

15.
Drought can affect both the quantity and quality of water in lakes and reservoirs, yet larger, highly managed waterbodies, such as Lake Mead, may be somewhat buffered from drought effects. From 2000 to present, Lake Mead has experienced a 71% decline in volume; however, influent water quality has remained high and consistent outflow volumes through Hoover Dam have been maintained. Furthermore, management activities, such as increased removal of phosphorus by wastewater dischargers and legacy contamination cleanup efforts, have been initiated since the drought began. These efforts have led to small improvements in values of water quality parameters, such as phosphorus, nitrogen, and perchlorate, despite loss of volume for dilution of constituents, and consequently, decreased residence time. As the drought continues, Lake Mead is projected to continue declining in volume, inflows are projected to become warmer, and the population of Las Vegas is projected to grow, potentially adding additional stress to the hydrologic system. Maintenance of outflow may mitigate some potentially negative consequences, and understanding the drivers behind continued high water quality despite prolonged drought is important to continue to maintain the health and vitality of the entire Lower Colorado River Basin.  相似文献   

16.
高氯酸盐是一种甲状腺毒素,它会干扰碘的吸收,阻碍甲状腺的产生,影响胎儿、儿童脑部的发育,甚至造成脑部的损伤。随着检测技术的发展,其在世界范围内的水体中陆续检出,牛奶、瓶装饮料、桶装水、土壤、植物中检出高氯酸盐也随后出现。文章参考大量文献,对高氯酸盐监测分析方法进行了详细论述。  相似文献   

17.
ABSTRACT: The detection of gradual trends in water quality time series is increasing in importance as concern grows for diffuse sources of pollution such as acid precipitation and agricultural non-point sources. A significant body of literature has arisen dealing with trend detection in water quality variables that exhibit seasonal patterns. Much of the literature has dealt with seasonality of the first moment. However, little has been mentioned about seasonality in the variance, and its effect upon the performance of trend detection techniques. In this paper, eight methods of trend detection that arise from both the statistical literature as well as the water quality literature have been compared by means of a simulation study. Varying degrees of seasonality in both the variances and the means have been introduced into the artificial data, and the performances of these procedures are analyzed. Since the focus is on lake and ground water quality monitoring, quarterly sampling and short to moderate record lengths are examined.  相似文献   

18.
Wetlands constitute a significant source of life since they incorporate unique habitats with endemic and migrant species. They also contribute to the preservation of high global biodiversity and they are under protection according to EU legislation. Nevertheless, during the last century, significant degradation has been observed in wetlands, mainly due to intensification of agriculture and poor water management practices. Calcareous fens habitat with the endangered species Cladium mariscus and Carex spp. is an ecologically significant wetland that undergoes great ecological stresses globally, due to the irrational use of water resources. In Trichonis lake, Western Greece, this habitat has been under deterioration during the last 50 years due to the lack of a sustainable water management plan that has caused destabilization of the hydrologic balance and high water level fluctuations. This human induced hydrologic regime has led to seasonal shifting between drought and flooding which constitute unfavorable conditions for this fen habitat and as a result significant elimination of this ecosystem extent has occurred. This study has adopted technologically advanced scientific methods such as GIS applications and remote sensing techniques to quantify the existing water resources and formulate a sustainable management scheme by considering both anthropogenic water uses and environmental protection.  相似文献   

19.
Towards water security: political determination and human adaptation crucial   总被引:11,自引:0,他引:11  
Although high-level attention has been drawn to the escalating world water problems, few changes are noticeable in terms of actual management of the water resource. Politicians continue to be misled by the apparent simplicity of water. The environment-oriented community tends to focus only on problems arising from man-induced side-effects, and most people tend to take water for granted. The double challenge of providing adequate water supplies and meeting increasing food requirements of expanding populations, in addition to already existing water management problems, requires special attention. In addition, the intensifying pollution of water systems will have to be dealt with. Considerable human adaptation to physical realities as well as ingenious action are needed.
There is a brief discussion of the risk of hydrocide, a condition of serious water-quality degradation where available water is no longer sufficient, or cannot be used for the purposes needed. However, the main focus of the paper is on water quantity issues, highlighting the confusion arising from different methods of assessing water scarcity. Levels of regional water scarcity predicaments are discussed in terms of distinct regional clusters. Attention is drawn to the limitations of dry climate regions to achieve food self sufficiency, and the emerging need in many areas to import food; related trade and price aspects are also discussed. A distinction is made between efficiency of use and efficiency of allocation.
The need for a global ethic regarding upstream–downstream water-sharing is stressed, especially in cases of consumptive (evaporative) use of water for cultivating crops, which may deplete river flows available to downstream users. In conclusion, four key concerns are highlighted that call for global consensus.  相似文献   

20.
Water reuse/recycle has gained much attention in recent years for environmental sustainability reasons, as well as the rising costs of fresh water and effluent treatment. Process integration techniques for the synthesis of water network have been widely accepted as a promising tool to reduce fresh water and wastewater flowrates via in-plant water reuse/recycle. To date, the focus in this area has been on water network synthesis problems, with little attention dedicated to the rare but realistic cases of so-called threshold problems. In this work, targeting for threshold problems in a water network is addressed using the recently developed numerical tool of water cascade analysis (WCA). Targeting for plant-wide integration is then addressed. By sending water sources across different geographical zones in plant-wide integration, the overall fresh water and wastewater flowrates are reduced simultaneously.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号