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111.
为了开发高效、低耗的含油污水处理工艺技术和设备,在吉林油田新立采油厂,对石油大学(北京)研制开发的高效油水分离器和高效过滤器处理油田污水的技术性能进行了现场测试研究。油水分离器采用斜通道波纹板作内构件,过滤器用炉渣做滤料。现场实验表明:高效油水分离器和高效过滤器串联处理油田污水,不论污水含油量高低,其过滤器出口水中含油量不高于10mg/L者达94%:过滤器出口水中悬浮物不高于10mg/L者占86%。结果说明该套装置在油和悬浮物的脱除及操作方面性能优异。有推广应用前景。 相似文献
112.
113.
金属氢氧化物包被砂过滤柱吸附与去除水体中的微生物 总被引:1,自引:0,他引:1
郑耀通 《应用与环境生物学报》2004,10(4):475-479
以氢氧化铁与氢氧化铝原位沉积包被砂作介质的过滤柱 ,用于去除脱氯自来水中人为污染的高浓度脊髓灰质炎病毒PV1、脆弱拟杆菌噬菌体B .fp和大肠杆菌E .coli.结果显示 ,包被修饰砂颗粒表面Zeta电动势由原来的 - 4 2 .8mV上升到 5 4 .7mV ,并因此提高了对微生物的吸附去除能力 .修饰砂过滤柱经 12 .5d连续过滤 30 0L水样后 ,仍可使进水微生物浓度分别高达n(cfu) /mL-1=5 .2× 10 6、2 .4× 10 5、2 .3× 10 5的E .coli、B .fp和PV1去除 92 %、97.2 %和 99.6 % .而未修饰砂柱 ,在相同条件下仅分别去除 5 3%、5 9%和 70 .6 % .修饰砂柱可在较大pH变化下稳定高效地去除微生物且在中性条件下效果最佳 ,这与未修饰砂柱明显不同 .扫描电镜显示 ,两种砂具有明显不同的表面结构 .修饰砂柱流出液中检测不到用于包被的铁、铝金属 ,说明氢氧化铁、氢氧化铝修饰物同砂结合牢固并因此提高了砂过滤柱的使用寿命 .修饰砂过滤介质可为饮用水处理提供更为安全可靠的去除病原微生物方法 .图 4表 4参 19 相似文献
114.
In 1990, the Government and Parliament of the Netherlands decided on a new national policy for coastal defence. To ensure
the enduring safety of the low-lying polders as well as the sustainable preservation of the coastal dunes, it was decided
to maintain the coastline in its 1990 position.
The main method for coastline preservation in the Netherlands is beach nourishment. Since 1991, approximately 7 million m3 of sand is added to the Dutch beaches annually. From an evaluation study of sand nourishment projects it is concluded that
nourishment is an effective and efficient method to preserve the coastline. The evaluation study also proves that nourishment
projects should be ‘tailor-made’, taking the local morphological and hydraulic conditions into account. The first results
of an experimental shoreface nourishment are discussed.
The choice for nourishment as the principal method to combat erosion is well in line with the intention to restore the natural
dynamics of the dune-coast in the Netherlands. The key probably is a less strict policy with regard to the maintenance of
the foredunes. Plans for the development of typical coastal features such as slufters*, wash-overs, blow-outs and mobile dunes are currently under discussion.
A slufter is a breakthrough in the first dune-ridge whereby the sea invades former dune slacks or beach plains situated behind
the duneridge. In this way a tidal marsh is formed within the dune zone. 相似文献
115.
The planning and management of coastal sites in Catalonia has been mainly concerned with rendering beaches functional for
mass frequentation. This has caused serious problems for the beaches, including the alteration of dune formation processes
and the destruction of beach vegetation and habitats. Municipal capacity to plan and manage beaches is theoretically very
limited and relegated to the design of plans related to the maintenance of facilities for beach users. Nonetheless, a singular
experience, led by a local council in the metropolitan area of Barcelona demonstrates the crucial role that a local administration
can play in achieving a balance between habitat preservation and social use based on sustainable coastal management objectives,
in spite of a restrictive legislation. 相似文献
116.
The machair sand dune systems of the Outer Hebrides of Scotland are a unique habitat, which is rare within both a global and
European context. Unusually, the machair habitat also represents an agricultural resource that is very important to the Hebridean
people, having been subject to both grazing and cultivation throughout the historical period. Following designation as an
Environmentally Sensitive Area (ESA) in 1988, the machairs of South Uist have been studied with the aim of understanding the
links between agricultural practice and their plant community and ecosystem dynamics. This research focused primarily on the
effects of cultivation practices and their role in maintaining plant species richness and community and ecosystem stability.
Within two carefully selected areas, the successional plant communities of machair at different stages of recovery following
ploughing and cultivation of cereals and potato patches or ‘lazy beds’ were identified at both a macro- and micro-level. Investigations
of the vegetation recovery processes on turves taken from newly ploughed land indicated that the initial stages of recolonization
are characterized primarily by rapid vegetative reproduction and growth, although re-vegetation by seeds is also an important
factor. The implications of these findings for the long-term management of machair plant communities are discussed and in
particular the need to maintain old cultivation practices such as shallow ploughing. The need for more detailed research into
both seed banks and seed rain and into processes of vegetative reproduction is stressed.
Nomenclature: Clapham et al. (1981) and Stace (1991, 1997) for vascular plants; Hubbard (1984) for grasses; Pankhurst & Mullin (1991) for
the regional flora; Dobson (1992) for lichens; Watson (1981) for mosses and liverworts. 相似文献
117.
河流水体受污染后,在自然环境因素的影响下由各种物理、化学及生物作用能得到一定的净化。哈尔滨市松花江段河流水质净化作用主要包括稀释、吸附、江底沉积物的机械过滤与吸附和絮凝沉淀作用。哈尔滨市松花江断面正处于河流侵蚀与堆积交替动态平衡中,可不断提供新的活性表面,使河底沉积物的净化作用持久不衰。该特殊的地质条件是本段河流保持较强净化作用的关键,妥善利用水环境净化能力是一种经济有效的水污染控制手段。 相似文献
118.
选取6种不同后整理方法处理的涤纶针刺滤料,通过实验研究探索不同后整理方法对袋式除尘器滤料过滤性能的影响关系。结果表明:过滤效率方面,在1 m/min过滤风速下,6种滤料对粒径≥0.26 μm的颗粒物的分级过滤效率分别为轧光滤料≥47.74%、烧毛-轧光滤料≥54.82%、PTFE涂层滤料≥65.14%、PTFE浸渍≥61.86%、覆膜滤料≥97.54%、抗静电滤料≥49.09%,PTFE覆膜、涂层、浸渍后整理方法对滤料过滤效率的提高有显著作用;过滤阻力方面,PTFE覆膜、浸渍滤料的过滤阻力远大于其他4种滤料,PTFE覆膜、浸渍后整理方法可大幅增大滤料过滤阻力,而其他4种后整理方法对滤料过滤阻力的影响差距不大;过滤品质因数方面,品质因数Q值由大到小为:PTFE涂层滤料 > 抗静电滤料 > 烧毛-轧光滤料 > 轧光滤料 > 覆膜滤料 > PTFE浸渍滤料,综合滤料的过滤效率和阻力因素,涂层后整理方法可使滤料具有低阻高效的性能特征。 相似文献
119.
对抚顺石化公司化工塑料厂苯乙烯废水活性炭吸附装置的预处理设施、活性炭吸附及再生性能进行了评价,分析了出水水质超标的主要原因,用混凝沉淀-砂滤流程改进了原处理工艺,使出水水质得到了显著改善。 相似文献
120.
西北地区沙尘暴引发的荒漠化问题 总被引:4,自引:2,他引:4
从西北地区继1993~1995年连续3a出现沙尘暴之后,1996年甘肃和内蒙古西部的阿盟等地再次遭到沙尘暴的袭击入手,分析了沙尘暴发生的原因,指出它归根结底是荒漠化的直接后果。概述了荒漠化的状况及危害,并分析了其成因。 相似文献