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841.
成都市活水公园人工湿地系统10年运行回顾 总被引:8,自引:1,他引:7
成都市活水公园是1997年建成的世界上首座以展示"人工湿地水处理系统"和"仿峨眉山亚热带自然植被"为主要内容的、以水保护为主题的生态公园。它所展示的人工湿地处理系统工程,现己正常运行了10年。本文通过回顾10年来活水公园人工湿地工程设计、建设与运行的经验,结合当前己建和在建的人工湿地工程中所存在的一些问题,提出一些看法与建议。供从事人工湿地工程设计、施工及管理人员参考。 相似文献
842.
In Europe, the use of direct methods using lysimeters for measuring water and solute flow in soils increased in recent years.
Large weighable lysimeters are best suitable for obtaining reliable data about seepage water quantity and quality. Field lysimeters
– lysimeters built in directly in agriculturally used areas – of high technical standard allow a precise determination of
the influence of different cropping systems on groundwater quality. They combine the advantages of true field conditions and
laboratory possibilities of varying parameters, handling and maintenance. Due to the specific needs of each application the
instrumentation varies. Based on general remarks on the advantages of precise weighing lysimeters four standardized lysimeter
configurations are presented. Beside the specific needs of design and setup of lysimeter stations, there is need to define
general requirements to enable comparable results based on standardized basic design and to reduce individual mistakes. 相似文献
843.
Reiner Schroll Sabine Grundmann Ulrike Dörfler Bernhard Ruth Jean Charles Munch 《Water, Air, & Soil Pollution: Focus》2008,8(2):209-216
Several lysimeter scenarios and approaches exist to study the fate of agro-chemicals or contaminants from deposition in soil
columns. In many systems just transport and leaching of the parent compound is followed, in some systems the leaching and
transport of the metabolites is investigated as well. In more sophisticated lysimeter systems the volatilization and also
the mineralization of the applied chemicals can be additionally monitored. Depending on the lysimeter system used and on the
fact whether the applied chemicals are 14C-labeled or not, different results and various interpretations of the results might be achieved. Different lysimeter systems
are described in this paper and a real dataset of a specific lysimeter experiment was transferred and evaluated in a virtual
approach in the different lysimeter systems in order to show the advantages and disadvantages of the various systems. 相似文献
844.
An entrained-flow system has been designed and constructed to simulate in-flight mercury capture by sorbents in ducts of coal-fired
utility plants. The test conditions of 1.5 s residence time, 140°C temperature, 4.5 ppbv inlet Hg0 concentration, and 0–20 lb/MMacf sorbent injection rates were chosen to simulate conditions in the ducts. Novel oxidants
developed in previous fixed-bed tests and novel sorbents derived from the novel oxidants were tested for their Hg0 capture in the entrained-flow system to examine the possibility of using those sorbents in a full-scale system. Darco-FGD
and Darco Hg-LH served as benchmark sorbents with which mercury control capability of the novel oxidants and novel sorbents
could be compared. The test results showed that the novel oxidants have remarkable Hg0 oxidation capability, and the novel sorbents showed a better performance in Hg0 removal than Darco Hg-LH. 相似文献
845.
Source water protection planning (SWPP) is an approach to prevent contamination of ground and surface water in watersheds where these resources may be abstracted for drinking or used for recreation. For SWPP the hazards within a watershed that could contribute to water contamination are identified together with the pathways that link them to the water resource. In rural areas, farms are significant potential sources of pathogens. A risk-based index can be used to support the assessment of the potential for contamination following guidelines on safety and operational efficacy of processes and practices developed as beneficial approaches to agricultural land management. Evaluation of the health risk for a target population requires knowledge of the strength of the hazard with respect to the pathogen load (massxconcentration). Manure handling and on-site wastewater treatment systems form the most important hazards, and both can comprise confined and unconfined source elements. There is also a need to understand the modification of pathogen numbers (attenuation) together with characteristics of the established pathways (surface or subsurface), which allow the movement of the contaminant species from a source to a receptor (water source). Many practices for manure management have not been fully evaluated for their impact on pathogen survival and transport in the environment. A key component is the identification of potential pathways of contaminant transport. This requires the development of a suitable digital elevation model of the watershed for surface movement and information on local groundwater aquifer systems for subsurface flows. Both require detailed soils and geological information. The pathways to surface and groundwater resources can then be identified. Details of land management, farm management practices (including animal and manure management) and agronomic practices have to be obtained, possibly from questionnaires completed by each producer within the watershed. To confirm that potential pathways are active requires some microbial source tracking. One possibility is to identify the molecular types of Escherichia coli present in each hazard on a farm. An essential part of any such index is the identification of mitigation strategies and practices that can reduce the magnitude of the hazard or block open pathways. 相似文献
846.
847.
太阳能污泥干化在欧洲的应用 总被引:2,自引:0,他引:2
太阳能污泥干化指的是利用太阳能为主要能源对污水处理厂污泥进行干化和稳定化的污泥处理技术。该技术运用太阳能,借助传统温室干燥工艺,具有低温干化、运行费用低廉、操作简单、运行安全稳定、干化后的污泥仍保留原有的农用价值等特点。该文主要介绍了该工艺的工作原理及流程,工艺设计参数及其与传统热干化技术相比的优缺点,并简要介绍了该工艺在欧洲市场上的商业应用。 相似文献
848.
建设项目恶臭污染和治理的现状 总被引:3,自引:0,他引:3
介绍了建设项目恶臭的分类与来源,简述了恶臭处理的主要方法,尤其是生物治理技术的发展,并对未来的发展趋势进行了预测。 相似文献
849.
850.
海洋巨藻(Durvilaea potatorum)生物吸附剂对Hg~(2 )的吸附动力学研究 总被引:2,自引:0,他引:2
对经特殊的稳定化预处理所得的海洋巨藻 (Durvillaeapotatorum)生物吸附剂对Hg2 的吸附动力学进行了研究 ,报导了不同Hg2 初始浓度、温度以及生物吸附剂平均粒径下动态吸附量与时间的关系 .结果显示 ,各吸附动力学曲线呈优惠型 ;当生物吸附剂平均粒径为 0 .45mm时 ,Hg2 的半饱和时间tS均不超过 6 0min ;Hg2 初始浓度和生物吸附剂粒径越小 ,吸附温度越大 ,达到吸附平衡所需的时间越短 .在测试范围内 ,生物吸附剂的平衡吸附容量与粒径和温度无关 .同时考察了吸附过程中的传质效应并对液膜传质系数kL进行了关联 ,结果表明 :当吸附时间t≤tS时 ,Hg2 的吸附速率为液膜传质控制 ;在测试范围内 ,kL为 0 .0 40 7~ 0 .112cm/s.本研究结果为利用海洋巨藻 (Durvillaeapotatorum)生物吸附剂处理含汞废水的规模化应用提供了一定的依据 .图 5表 2参 11 相似文献