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661.
针对城市垃圾含水率高、成分复杂的特点,采用静置沥水5天后再筛分处理的措施,垃圾的含水率可去除10%~15%,增强了机械分选效果。对筛下物进行生物堆肥处理,两次发酵约35天后,产品基本达到无害化、稳定化的要求。同时,对筛上物进行了卫生填埋,渗滤液经过沉淀和UASB工艺预处理后与邻近污水厂污水合并处理,臭气经生物滤池后也得到有效控制。  相似文献   
662.
微滤膜技术及应用研究*   总被引:3,自引:0,他引:3  
随着膜制造技术的发展,微滤膜在油田采出水处理中具有越来越大的优势。文章对微滤膜的特点和过滤分离原理进行了阐述,对比分析了有机高分子微滤膜、无机陶瓷微滤膜和复合微滤膜各自的优缺点、制备工艺以及在油田中的应用情况,针对微滤膜在采油污水处理中膜通量下降快,使用周期短等弱点提出了防止膜污染和膜清洗的措施,并对微滤膜的发展及今后在油田中的应用提出了建议和展望。  相似文献   
663.
分析了在油田开发工程可能对水源地产生影响的三类事故,筛选出风险最大的事故是注水井井壁泄漏事故。采用地下水中污染物三维迁移转化模型和MODFLOW、MT3D模拟计算软件对某地下水水源地可能受到的石油类污染进行数学模拟,并针对模拟结果提出了污染预防和控制措施。  相似文献   
664.
The concentrations of metals in the buried marine sediment and groundwater were differently affected by land reclamation. Nine metals (V, Cr, Mn, Co, Ni, Cu, Zn, Cd and Pb) in sediment and coastal groundwater from reclamation areas in Shenzhen were examined. The gradually decreased concentrations (V, Cr, Mn, Ni, Cu, Zn) in sediment and relatively higher concentrations (V, Cr, Mn, Co, Ni, Cu and Cd) in groundwater within reclamation areas were observed. The increase of V, Cr, Mn, Ni, Cu and Cd concentrations in groundwater within reclamation areas subsequently after land reclamation should be resulted from the mobilization of these metals accumulated in the sediment. These metals appear to be easily mobilized from solid phase to solution phase after reclamation. The physico-chemical changes such as reduction in pH and salinity in water environment induced by land reclamation appear to be responsible for metal mobility in the sediment-groundwater system.  相似文献   
665.
针对城市生活污水处理厂滞留污水中的高浓度难降解污染物质,提出采用生物酶催化技术对滞留污水进行应急处置,可在最短的时间内有效去除污染物,无二次污染,为环境污染应急处置提供了有效措施。  相似文献   
666.
随着城市的快速发展,城市生活垃圾对环境的危害越来越大,已经成为影响城市居住环境的重要污染源,如何进行城市生活垃圾的收集与处理显得至关重要。米东区作为乌鲁木齐市新型工业城区的代表,其经济虽然取得了飞速发展,但其城市居住环境却未得到足够地重视。鉴于此,围绕乌鲁木齐市新型工业城区的生活垃圾分类收集和处理现状展开了社会调查,选取乌鲁木齐市米东区作为靶区,随机选取70户人家进行了入户问卷调查,对调查结果进行了统计分析,得出了乌鲁木齐市米东区家庭生活垃圾分类收集及处理的特点,进而指出了新型工业城区垃圾分类工作存在的主要问题,根据影响城市家庭生活垃圾产生量的因素,针对如何更好的实现垃圾的分类收集工作提出了相应的建议。  相似文献   
667.
垃圾渗滤液水质特性研究进展   总被引:5,自引:0,他引:5  
垃圾渗滤液已被公认为是高风险高污染废水,对地下水与地表水具有极大的潜在危害性。由于渗滤液具有高污染、水质水量差异大、难控等特点,使得其有效处理十分棘手。近年来国内外对渗滤液的研究十分广泛,本文结合国内外渗滤液相关研究中水质特性相关部分,从渗滤液的一般特性,溶解性有机质及危险物质等方面对渗滤液水质进行阐述,有助于深入了解渗滤液水质及其变化规律,从而为渗滤液的有效处理提供理论依据。  相似文献   
668.
In 2006, we used the U.S. Coast Guard’s Automatic Identification System (AIS) to describe patterns of large commercial ship traffic within a U.S. National Marine Sanctuary located off the coast of Massachusetts. We found that 541 large commercial vessels transited the greater sanctuary 3413 times during the year. Cargo ships, tankers, and tug/tows constituted 78% of the vessels and 82% of the total transits. Cargo ships, tankers, and cruise ships predominantly used the designated Boston Traffic Separation Scheme, while tug/tow traffic was concentrated in the western and northern portions of the sanctuary. We combined AIS data with low-frequency acoustic data from an array of nine autonomous recording units analyzed for 2 months in 2006. Analysis of received sound levels (10–1000 Hz, root-mean-square pressure re 1 μPa ± SE) averaged 119.5 ± 0.3 dB at high-traffic locations. High-traffic locations experienced double the acoustic power of less trafficked locations for the majority of the time period analyzed. Average source level estimates (71–141 Hz, root-mean-square pressure re 1 μPa ± SE) for individual vessels ranged from 158 ± 2 dB (research vessel) to 186 ± 2 dB (oil tanker). Tankers were estimated to contribute 2 times more acoustic power to the region than cargo ships, and more than 100 times more than research vessels. Our results indicate that noise produced by large commercial vessels was at levels and within frequencies that warrant concern among managers regarding the ability of endangered whales to maintain acoustic contact within greater sanctuary waters. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
669.
A bioeconomic model of a single-species fishery with a marine reserve   总被引:2,自引:0,他引:2  
This study examines the impact of the creation of marine protected areas (MPAs), from both economic and biological perspectives. In particular, we examine the effects of protected patches and harvesting on resource populations. We conclude that protected patches are an effective means of conserving resource populations, even though extinction cannot be prevented in all cases. We discuss the dynamic optimization of a harvest policy by choosing E(t), the harvesting effort, as the dynamic variable. We also discuss the optimal equilibrium harvest policy and explain the biological and bioeconomic interpretations of the results.  相似文献   
670.
Ecosystem-based management requires understanding of food webs. Consequently, assessment of food web status is mandatory according to the European Union’s Marine Strategy Framework Directive (MSFD) for EU Member States. However, how to best monitor and assess food webs in practise has proven a challenging question. Here, we review and assess the current status of food web indicators and food web models, and discuss whether the models can help addressing current shortcomings of indicator-based food web assessments, using the Baltic Sea as an example region. We show that although the MSFD food web assessment was designed to use food web indicators alone, they are currently poorly fit for the purpose, because they lack interconnectivity of trophic guilds. We then argue that the multiple food web models published for this region have a high potential to provide additional coherence to the definition of good environmental status, the evaluation of uncertainties, and estimates for unsampled indicator values, but we also identify current limitations that stand in the way of more formal implementation of this approach. We close with a discussion of which current models have the best capacity for this purpose in the Baltic Sea, and of the way forward towards the combination of measurable indicators and modelling approaches in food web assessments. Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01692-x.  相似文献   
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