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1.
粒状滤料过滤理论的主要内容是过滤机理、过滤方程式和反冲洗机理。过滤机理有悬浮颗粒的迁移机理、悬浮颗粒的吸附机理和脱落机理等。过滤在水澄清的同时,滤层的水头损失增加,整个过程涉及因素多而且复杂,过滤方程式很难得到解析性的答案,所以过滤方程对过滤过程只起定性的作用。现在反冲洗机理的研究认为,悬浮颗粒从滤料表面脱落是水流剪切和颗粒碰撞综合作用的结果。  相似文献   

2.
研究了造粒粉煤灰的最大磷吸附量、磷吸附速率等吸附特征,以及颗粒粒径、磷浓度、水力负荷对景观水除磷效果的影响。还进行了为期21天的连续过滤试验,发现滤床在高水力负荷条件下能持续地去除景观水中的磷。  相似文献   

3.
<正>由青岛路博宏业环保技术开发有限公司开发的挥发性有机废气吸附+催化燃烧净化技术,适用于工业挥发性有机废气(VOCs)治理。主要技术内容一、基本原理采用有机废气吸附脱附一体机,集废气预处理、吸附、脱附、新风换热、催化燃烧、引风系统多种工序于一体。在吸附风机的作用下,废气首先进入前置过滤箱体,将废气中的颗粒物过滤、阻截。由前置过滤器分别进入两侧吸附脱附箱体(中间设有旁路保温隔层,在有  相似文献   

4.
《中国环保产业》2005,(4):47-47
由山东恒利石油化工有限公司开发的工业废水处理及回用技术适用于炼化企业、大型化工企业和发电厂。主要技术内容一、基本原理根据工业企业达标外排污水水质特点进行吸附过滤处理,经吸附过滤处理后的污水回用于循环冷却水系统开发出高效杀菌剂、缓蚀阻垢剂、黏泥剥离剂及相应的  相似文献   

5.
以磁铁矿滤料与石英砂滤料为填设滤料层的级配模式一直广泛应用于油田含聚污水处理过程中,但这种滤料级配与污水过滤性能之间的影响关系及规律认识却较为缺乏,本文以悬浮粒子吸附与截留形成的聚集特征为切入,定量分析出水水质特性,对含聚污水过滤过程中滤料级配的影响效果展开数值模拟研究。研究认为:磁铁矿滤料层厚度较大的级配模式过滤具有更好的悬浮粒子吸附与截留效果,对更小粒径悬浮粒子过滤能力更优,但滤料填充高度比与过滤效果存在一定适配性;以1.28以上磁铁矿滤料厚度较大的级配模式过滤较低含聚浓度污水、以1.67以上磁铁矿滤料厚度较小的级配模式过滤较高含聚浓度污水,均可以使出水悬浮固体颗粒与油滴含量均低于5mg/L,满足过滤出水水质指标要求。  相似文献   

6.
BSF型注水井洗井液处理装置根据气浮、过滤等工艺原理,成功地解决了油田注水井洗井水的污染问题,经现场生产性试验证明,处理效果达到排放甚至回用标准。本文详细介绍了该装置的工艺流程、工作原理、试验效果及其应用价值等情况。  相似文献   

7.
为解决稠油废水达标排放问题,构建了5m3/h中试实验装置,以经过除油、浮选和过滤预处理的 富含溶解性有机化合物、氮磷缺乏的低浓度难生化稠油废水为原水,开展了半饱和褐煤活性焦预吸附-生物降解-活性焦吸附、活性焦吸附-生物降解-臭氧催化氧化、臭氧催化预氧化-生物降解-臭氧催化氧化3种不同组合工艺 深度处理稠油废水研究。实验各运行30d。结果表明:在确保处理后水质满足辽宁省DB21/1627—2008《污水综合排放标准》的条件下,3种工艺成本均可控制在6元/m3以内,半饱和褐煤活性焦预吸附-生物降解-活性焦-吸附工艺处理效果最好,成本最低,仅为4.31元/m3。采用吸附生化出水且尚未饱和的活性焦吸附原水,既提 高了活性焦的利用率,也降低了生化降解的负荷,为稠油污水处理厂深度处理达标外排工程建设提供了技术依据。  相似文献   

8.
《中国环保产业》2002,(4):42-42
由浙江洁华环保科技有限公司开发、浙江省环境保护局推荐的LCM型长袋脉冲除尘器,适用于电力、冶金、化工、建材及垃圾焚烧行业废气净化。主要技术内容一、基本原理利用布袋过滤除尘机理,除去含尘气体中的粉尘。当含尘气体从下部锥体进入除尘器,粉尘被阻留在滤袋表面上,经过滤的净气进入上气箱,经排风管排出。随过滤工况的进行,滤袋阻力升高,由自动控制仪控制脉冲阀、离线阀、进行逐室逐排脉冲清灰,使滤袋恢复过滤能力。二、技术关键离线脉冲喷吹技术,克服了粉尘“再吸附”现象,提高了清灰效果,降低设备阻力达到长滤袋(为传统…  相似文献   

9.
以磁铁矿滤料和石英砂滤料为填设滤料层的级配模式,一直被广泛应用于油田含聚污水处理过程,但目前这种滤料级配对过滤性能的影响及规律认识较为缺乏。文章从悬浮粒子(包含悬浮固体颗粒和油滴)吸附与截留形成的聚集特征切入,定量分析出水水质特性,对含聚污水过滤过程中滤料级配的影响效果展开数值模拟研究。研究表明:磁铁矿滤料层厚度较大的级配模式过滤,对悬浮粒子具有更好的吸附与截留效果,对小粒径悬浮粒子的截留能力更优,但滤料填充高度比与过滤效果存在一定适配性;以填充高度比1.28以上磁铁矿滤料厚度较大的级配模式过滤较低含聚浓度的污水,及以填充高度比1.67以上磁铁矿滤料厚度较小的级配模式过滤较高含聚浓度的污水,均可以实现出水悬浮固体颗粒和油滴含量低于或约等于5 mg/L,满足大庆油田含聚污水二级过滤出水回注水质指标要求。  相似文献   

10.
回收涂布生产废气中甲苯的新型装置   总被引:4,自引:0,他引:4  
文章介绍了从涂布生产废气中回收甲苯的新型自动化回收工艺和装置。与传统的颗粒活性炭装置相比,该装置由于采用了性能优越的吸附材料和先进的工艺设计,使甲苯的回收率达95%以上,而且回收的甲苯品质好,可以直接作为原料使用,实现了清洁生产和废气资源化,收到了很好的环境效益和经济效益。  相似文献   

11.
当前发展环保产业需要重新认识的几个问题   总被引:6,自引:0,他引:6  
本文就当前在社会主义市场经济体制下如何更好地加快环保产业的发展,提出了如下看法:目前环保产业应是以服务业为重点内容,以市场化、产业化为其发展方式的一个综合性新兴产业,要开展以企业为主体的经济活动,建立政府激励机制,改变以政府为主体的投资机制,并加强对环保设施运营的监督管理。  相似文献   

12.
本文介绍了成都麻羊品种特征、体型结构、生产性能及其产区概况,讨论了保种选育的方向、指标和种群建设规模;提出了规划保种区、建立良种繁育体系、组建保种核心群、严格选种选配、科学饲养、合理培育、健全卫生防疫制度等配套技术措施,以及强化管理、加强协作、扶持发展专业户、搞好技术培训、合理利用等组织措施。  相似文献   

13.
We draw attention to a number of key factors in the evaluation of major projects, such as smelters, which are highly capital- and energy-intensive as well as export-orientated. The practice of justifying such projects by upvaluing foreign exchange is considered, as is the cost of distortion. Export efficiency is introduced as the key criterion: the efficiency of some recent smelter proposals in Oceania was between 36 and 50 cents in the dollar. A correct power price is essential: hydropower (in contrast with hydroenergy) should be priced as a depletable resource.  相似文献   

14.
周庄旅游者的结构特征及利益追求   总被引:1,自引:0,他引:1  
旅游客源市场由不同结构特征的旅游者组成,其利益追求各不相同,对此加以分析,可以制定正确的营销策略,提供科学依据.以周庄为案例,采用随机抽样问卷调查法,分别对周庄旅游者的性别结构、年龄结构、文化结构、家庭收入水平结构和职业结构进行了分析.结果显示,周庄旅游者以男性游客为主体,25~44岁的中青年游客占大多数;文化程度以大专及以上层次为主,职业构成比较分散,企事业管理人员居多;家庭月收入水平高于全国平均水平.对旅游者的利益追求进行了初步的探讨,并结合游客结构特征和利益追求的分析结果,提出了周庄未来旅游产品的营销策略.  相似文献   

15.
岳喜云 《四川环境》2009,28(3):11-13
本文采用改进的BCR三步连续提取法对河北某食道癌高发地土壤中钙、镁进行了形态分析及提取序列的研究。实验表明:该地区土壤中镁主要以残渣态形式存在(占总量的83.66%-88.36%),钙则受提取序列的影响很大,在第一提取序列中,以酸溶态为主(74.11%-83.38%);第二提取序列中,以有机物结合态为主(78.12%-97.17%);第三、四提取序列中,以氧化物结合态为主(87.49%-103%)。提取剂的加入顺序明显影响到钙的各个形态的真实含量。  相似文献   

16.
渗灌——设施园艺先进的节水灌溉技术   总被引:19,自引:0,他引:19  
渗灌具有降低室内湿度、改善土壤环境、节约灌溉用水、减少肥料用量、省工省时、价格适中等优点,是目前设施园艺先进的节水灌溉技术。详细介绍了渗灌系统的结构,渗灌管的种类以及使用维护方法。  相似文献   

17.
With existing and proposed air-quality regulations, ecological disasters resulting from air emissions such as those observed at Copperhill, Tennessee, and Sudbury, Ontario, are unlikely. Current air-quality standards, however, may not protect ecosystems from subacute and chronic exposure to air emissions. The encouragement of the use of coal for energy production and the development of the fossil-fuel industries, including oil shales, tar sands, and coal liquification, point to an increase and spread of fossil-fuel emissions and the potential to influence a number of natural ecosystems. This paper reviews the reported responses of ecosystems to air-borne pollutants and discusses the use of animals as indicators of ecosystem responses to these pollutants. Animal species and populations can act as important indicators of biotic and abiotic responses of aquatic and terrestrial ecosystems. These responses can indicate long-term trends in ecosystem health and productivity, chemical cycling, genetics, and regulation. For short-term trends, fish and wildlife also serve as monitors of changes in community structure, signaling food-web contamination, as well as providing a measure of ecosystem vitality. Information is presented to show not only the importance of animals as indicators of ecosystem responses to air-quality degradation, but also their value as air-pollution indices, that is, as air-quality-related values (AQRV), required in current air-pollution regulation.  相似文献   

18.
循环经济是以科学发展观为统领,以先进的科学技术为基础,以低消耗、低排放、高效率为特征的集约化、内涵式经济增长模式。为了促使我国走上循环经济发展之路,就必须建立循环经济科技支撑体系,即以政府为主导、企业为主体、社会化服务机构健全的循环经济科技创新体系和完善的循环经济科技政策体系、法律法规体系以及绿色文化与教育体系。  相似文献   

19.
There is currently a lack of access to affordable sanitation in urban areas of Sub-Saharan Africa. This study evaluated the potential for resource recovery from innovative faecal sludge treatment processes to generate a profit that could help sustain the sanitation service chain. A total of 242 interviews were conducted in Accra, Ghana; Dakar, Senegal; and Kampala, Uganda to compare markets in different cultural and regional contexts. Products identified to have potential market value include dry sludge as a fuel for combustion, biogas from anaerobic digestion, protein derived from sludge processing as animal feed, sludge as a component in building materials, and sludge as a soil conditioner. The market demand and potential revenue varied from city to city based on factors such as sludge characteristics, existing markets, local and regional industrial sectors, subsidies, and locally available materials. Use as a soil conditioner, which has been the most common end use of treated sludge, was not as profitable as other end uses. These findings should help policy and decision makers of sanitation service provision to design financially viable management systems based on resource recovery options.  相似文献   

20.
ABSTRACT

This paper revisits the development of Toronto and Brussels’ local food policies by analysing reflexivity and co-learning as important dimensions within a Hybrid Governance Approach (HGA); it approaches the interaction between four forms of governance (bottom-up, networked, state, market-led) and the tensions between them as hybrid dynamics. Within this approach, reflexivity refers to the positionality of agents, i.e. to the ways local food actors embody as well as reflect on and reconsider their principles and practices through time. Closely related to reflexivity, co-learning involves agential interactions to co-construct enabling food policy delivery systems. The HGA is mobilised to understand the ways in which reflexive capacities, as well as co-learning, take place in the two cases and how they lay the basis of particular modes of (de)institutionalisation. Learning from the two cases’ trajectories, this paper highlights: (a) the role of key governance tensions as triggers as well as breeding grounds for reflexivity and co-learning outcomes; (b) the challenges of food movement actors to surmount or valorise key tensions in order to build accountable modes of food policy delivery through time; (c) the struggles to build legitimacy and accountability in local food movements through the development of bottom-linked organisations and governance modes.  相似文献   

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