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用固相萃取法萃取水和废水中的多菌灵,取浓缩纯化后的有机相直接进样到高效液相色谱仪,用二极管矩阵检测器检测,根据保留时间外标法定量. 相似文献
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引言目前,对造纸废水的治理措施主要有聚凝沉淀法、活性污泥法和浓缩燃烧法三种。浓缩燃烧法主要用于有机物浓度比较高的废水,但此法相当耗能。聚凝沉淀法和活性污泥法主要适合浓度低的废水,但所耗能量(占造纸能耗量之2%)和所花费用可在一年内生产210万千升的纸浆。因此单纯治理是不划算的 相似文献
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本工艺采用“反串联喷淋法”治理电镀酸碱漂洗水,“镀液减压浓缩双槽式闭路循环法”治理氰铜废水,“反喷淋法”治理焦磷酸盐镀铜、锡、镍三元合金废水,实现了环形电镀自动线废水治理闭路循环。“反串联喷淋”系借助于自动线的正常运转程序,利用一组自控设备与其同步,当 相似文献
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对己内酰胺生产过程废水的回用处理工艺进行了研究。以某己内酰胺化工厂的LUCAS出水作为研究对象,采用膜生物反应器和反渗透膜处理工艺,研究此系统对己内酰胺废水的处理效果。试验结果表明,膜生物反应器工艺适用于该化工厂的生产废水,出水COD平均值为31.33mg/L,平均浊度为0.2NTU,氨氮平均值为2.81mg/L,可以满足反渗透膜的进水要求。在浓缩倍数为3时,反渗透膜系统运行稳定,且产水可以满足化工部循环冷却水用再生水水质标准。 相似文献
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采用膜技术分离、浓缩氰化废水中的氰化物,既可以回收废水中的氰化物和贵重金属,提高企业经济效益和竞争力,又可以减少污染,确保环境安全。本文以某工程实例介绍了膜技术处理氰化废水的应用情况。 相似文献
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This two-part article gives an overview of the use of non-conventional water resources in developing countries. The first part presented below reviews United Nations involvement with the subject and its relationship to the International Drinking Water Supply and Sanitation Decade. The main emphasis of the first part is on the development of technology and markets for the various desalination processes — distillation, electrodialysis and reverse osmosis. The general costs of the various processes are compared.
The second part of the article (to be published in the April 1985 issue) concentrates on the other non-conventional water resources: transport of water by tanker and iceberg, waste water re-use and weather modification. For all the processes, examples are given and economic comparisons are made. It is concluded that it is always preferable to use conventional resources where available. However, in water-short areas, consideration might be given to the available non-conventional resources, and economic and technical comparisons made, before a final choice is reached. 相似文献
The second part of the article (to be published in the April 1985 issue) concentrates on the other non-conventional water resources: transport of water by tanker and iceberg, waste water re-use and weather modification. For all the processes, examples are given and economic comparisons are made. It is concluded that it is always preferable to use conventional resources where available. However, in water-short areas, consideration might be given to the available non-conventional resources, and economic and technical comparisons made, before a final choice is reached. 相似文献
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Mark M. Wilsnack David E. Welter Angela M. Montoya Jorge I. Restrepo Jayantha Obeysekera 《Journal of the American Water Resources Association》2001,37(3):655-674
ABSTRACT: As part of the Comprehensive Everglades Restoration Plan (CERP), various water supply projects have been proposed in a region located between the Miami metropolitan area and the extensive regional wetland systems that are part of the Everglades or remnant Everglades. A ground water flow model of the surficial aquifer within northern Miami‐Dade County was constructed using MODFLOW to evaluate the effects of these projects on water levels in the wetlands and the underlying surficial aquifer. The new Wetlands package was used to conjunctively simulate overland flow through these wetlands and the shallow ground water system. Comparisons of simulated to measured ground water levels and wetland stages were very satisfactory, where computed and measured water levels agreed within 0.5 ft over most of the period of record at nearly all of the monitoring sites. Temporal trends in water levels were also replicated. It was concluded that the assumptions and methodologies inherent to the Wetlands package were suitable for simulating regional wetland hydrology within the Everglades area. 相似文献
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Omar S. Abu-Rizaiza Abdullah M. Mohorjy 《Journal of the American Water Resources Association》1994,30(1):113-123
ABSTRACT: Due to the spread of Islam in the seventh century the number of pilgrims to the City of Makkah increased sharply, resulting in an acute water shortage. To solve this problem, galleries were built to collect water from the upstream of Wadi Naaman and transfer it to Makkah. Expansion of Makkah and the absence of any mapping of the galleries have resulted in the destruction of a part of the galleries. This caused a discontinuity of flow in the galleries and, consequently, the ground water table is rising at a rate of 0.48 m/yr, causing environmental problems. Research was conducted to rehabilitate the destructed part of the galleries, and to find an appropriate use for the ground water. The study found that the quality of the ground water is suitable for landscaping purposes, that is, for the irrigation of trees and ornamental plants. 相似文献
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This two-part article gives an overview of the use of non-conventional water resources in developing countries. The first part (published in the January 1985 issue) reviewed United Nations involvement with the subject, and its relationship to the International Drinking Water Supply and Sanitation Decade. The main emphasis of the first part was on the development of technology and markets for the various desalination processes — distillation, electrodialysis and reverse osmosis. The general costs of the various processes were compared.
The second part of the article (presented here) concentrates on the other non-conventional water resources: transport of water by tanker and iceberg, wastewater reuse and weather modification. For all of the processes examples are given and economic comparisons made. It is concluded that it is always preferable to use conventional resources where available.
However, in water-short areas, consideration might be given to non-conventional resouces. 相似文献
The second part of the article (presented here) concentrates on the other non-conventional water resources: transport of water by tanker and iceberg, wastewater reuse and weather modification. For all of the processes examples are given and economic comparisons made. It is concluded that it is always preferable to use conventional resources where available.
However, in water-short areas, consideration might be given to non-conventional resouces. 相似文献
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中国北方15个省、区、市耕地面积占全国的55%,灌溉面积占全国灌溉总面积的48%,而水资源总量仅占全国的20%。区域水资源短缺和农业的进一步发展,要求提高农业用水有效性。本文从水文学角度,研究了华北、西北和东北3个地区水土资源特征;分析了作物熟制和适水种植的节水效益、农田供水量与产量的函数关系、农田棵间蒸发量和控制措施,以及提高高产农田用水有效性等水文试验研究结果;介绍了河北省南皮节水农业试验区的研究模式。 相似文献
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丽江古城水环境现状与调控对策研究 总被引:5,自引:0,他引:5
水环境是丽江世界文化遗产地生态地质环境的重要组成部分。由于丽江城市化进程加快,对水环境保护不力,导致古城水污染加剧、水资源量衰减、景观生态用水不足和景观水质下降。通过强化水环境研究,加强水环境立法,进行水生态环境综合治理;实施以调剂古城周边地下泉水为主,拉市海调水为辅的丽江古城景观调水方案,可保护丽江古城水环境,为丽江古城世界文化遗产地的可持续发展提供保证。 相似文献
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This paper seeks to identify some promising policy options which could be part of a strategic and holistic effort to address India's future water challenges. Significant increases in agricultural water productivity would be a major factor in reducing the need for developing new water sources. Crop diversification, appropriately targeted to account for the present agricultural systems and available water resources, will increase productivity. Furthermore, much more emphasis needs to be placed on effective management of the groundwater resources through renewed efforts to enhance artificial recharge and conservation. Also, efforts should be revived to improve the existing surface irrigation systems. In particular, systems could be reconfigured to provide a more reliable water supply and allow effective community level management, where appropriate. Finally, while some of the increasing demands from domestic and industrial users will be met by the development of groundwater and reallocation of water from the agricultural sector, this will not be sufficient. Given that such conditions are emerging in states with high economic growth and relatively water scarce basins, this will require the further development of water resources. In some cases, these conditions along with the demand for reliable water for high value crops, will be part of the justification for inter‐basin transfers. 相似文献
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Thomas L. Huntzinger Michael J. Ellis 《Journal of the American Water Resources Association》1993,29(4):533-574
ABSTRACT: The Central Nebraska Basins (NAWQA) study unit includes the Platte River and two major tributaries, the Loup and Elkhorn Rivers. Platte River flows are variable in the western part of the study unit because of diversions, but the Loup and Elkhorn Rivers originate in an area of dune sand covered by grassland that generates consistent base flows. More frequent runoff in the eastern part of the study unit also sustains stream flow. Ground water in the study unit has no regional confining units and the system is a water table aquifer throughout. Macroinvertebrate and fish taxa at biological sampling sites in the state were related to stream flow. One of the four wetland complexes identified in the study unit includes habitat for threatened and endangered bird species. The study unit is an agricultural area that includes row crops, both irrigated and nonirrigated in the eastern and southern parts, and rangeland in the Sand Hills of the western part. A water quality assessment will be based on the differences in environmental setting in each of four subunits within the study unit.] 相似文献
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The Macquarie Marshes in Arid Australia and their waterbirds: A 50-year history of decline 总被引:3,自引:0,他引:3
We investigated the relationship between total annual flow of water in the Macquarie River and the extent of flooding in the
northern part of the Macquarie Marshes and trends in waterbird populations from 1983 to 1993. The amount of water in the Macquarie
River measured each year within the Macquarie Marshes explained about 86% of the variation in area flooded in the northern
part of this wetland. This allowed use of long-term data on flow at Oxley, a gauge within the Macquarie Marshes, as an index
to flooding. Annual flows at Oxley have decreased significantly for high and medium rainfall events in the catchment, despite
no trend in rainfall between 1944 and 1993. The area flooded by large floods has contracted by at least 40–50% during the
last 50 years (1944–1993). Water use has progressively increased upstream in the period, depriving the Macquarie Marshes of
water: 51% of all water passing Dubbo each year, a gauge 100 km upstream, reached the Macquarie Marshes in the period 1944–1953,
but by 1984–1993 this had declined to 21%. Numbers of species and density of waterbirds on the northern part of the Macquarie
Marshes declined between 1983 and 1993. Three other wetlands, not affected by water abstractions, showed no declines. We believe
the decline was due to wetland degradation as a result of decreased flooding. We estimated more than 88,000 waterbirds in
the Macquarie Marshes in October 1984, establishing the site as an important wetland site in Australia. The extent and viability
of this wetland will depend on maintaining or increasing the water supply. 相似文献