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111.
The long time scale of the climate change problem and the inherent nature of the carbon cycle bring important implications for present technology development efforts. Even if major technology improvements are achieved for non-carbon-emitting technologies such as energy-intensity improvements, wind, solar, biomass, and nuclear over the course of the 21st century, most examinations of potential future greenhouse emissions conclude that additional technology development will be required to stabilize greenhouse gas concentrations. The evelopment of an expanded suite of technologies including carbon capture and disposal, hydrogen systems and biotechnology hold the potential to dramatically reduce the cost of stabilizing greenhouse gas concentrations. This paper examines these technologies in the context of a global integrated assessment model of energy, agriculture, land-use, economics, and carbon cycle processes.  相似文献   
112.
In recent years there has been an increase in the intensity and frequency of environmental monitoring surveys at UK sewage sludge disposal sites. These have been carried out by the regulatory authorities and by the licensees. in order to ensure maximum efficiency, a coordinated and harmonised programme of monitoring has been developed. the programme concentrates on sediment chemical and biological quality but also includes assessments of water and fish quality

In England and Wales the Ministry of Agriculture, Fisheries and Food is the regulatory authority and the Water Authorities are the licensees. the Ministry's first priority is the collection of samples for temporal trend analysis but in addition, infrequent surveys are made to check the status of the disposal site and surrounding areas. in the periods between status surveys, regular spatial surveys designed to define the area of impact are carried out by the Water Authorities.  相似文献   
113.
设计了一种高效实用的钻井防污土建结构,该结构与原结构相比能杜绝处理渣泥流入废水沉砂池参与废水循环,也可防止废弃钻井液和掏罐泥浆水直接进入沉砂池,因此能更好地控制钻井废水浓度,一定程度上提高钻井废水处理达标率,同时该结构具有对处理水进一步隔油、净化等优点,现场推广应用后得到证实。  相似文献   
114.
市政污泥是污水生物处理过程中产生的城市固废,产量巨大、污染严重."十三五"期间中国污泥无害化处理任务艰巨,常规的污泥处理处置在二次污染、占地、能耗等方面具有局限,影响了在中国的广泛应用.污泥的能源化利用是兼具污泥量削减和新附加值产生的发展方向,本文围绕当前市政污泥能源化的研究、应用领域的发展加以讨论,探讨了污泥能源利用的潜能和存在的主要问题.  相似文献   
115.
稠油污水处理系统改造与絮凝剂筛选试验研究   总被引:2,自引:1,他引:2  
河南油田井楼稠油联合站含油污水中的污油和悬浮物含量较高,超过150mg/L。为此,对该处理系统进行了改造,并对絮凝剂的筛选进行了试验。结果表明:无机絮凝剂与有机絮凝剂联合作用,可对污水中所含有的污油和有机物杂质的悬浮物产生很好的絮凝沉降效果。加药浓度、加药顺序及沉降时间均对絮凝沉降效果有一定的影响。改造后的污水处理系统实现了污水达标回注,降低了无效回注费用。同时还回收了污油,降低了药剂成本,产生了十分明显的经济效益,每年节约成本约500万元。  相似文献   
116.
我国城市生活垃圾的处理和发展趋势   总被引:6,自引:0,他引:6  
城市生活垃圾给城市环境造成了严重污染,威胁了城市居民的生存环境和经济、社会的可持续发展。目前,国内采取的垃圾处理技术主要有卫生填埋、焚烧、堆肥等,热解技术由于具有资源回收率高、二次污染小、综合效益好等优点,越来越适合我国中小城市的垃圾处理。垃圾气化技术的研究成为当今世界的热点。此外,我国对垃圾衍生燃料的研究也刚刚起步。为促进城市持续、稳定的发展,提出了垃圾分类收集、分拣、综合利用垃圾处理技术的措施。  相似文献   
117.
Disposal of sewage sludge in the New York Bight Apex (12-Mile Dump Site) ceased at the end of December 1987. Previous efforts to quantify the effects of sludge were hindered by the inability to obtain true replication. the cessation of dumping afforded the opportunity to apply the technique of replication in time, also known as a Before/After, Control/Impact design. Conditionally, this method allows one to separate treatment effects from the natural differences that confound many environmental impact studies. the Environmental Processes Division of the Northeast Fisheries Center, National Marine Fisheries Service sampled the benthic environment of the New York Bight Apex from June 1986 through September 1989 using a sample design based on the technique of replication in time.

Three dominant species (rock crab, Cancer irroratus; little skate; Raja erinacea; and winter flounder, Pseudopleuronectes americanus) and total demersal finfish, collected by otter trawl, showed no statistically significant response to the cessation of disposal. American lobster (Homarus americanus) increased in local abundance, but this result was possibly confounded by a change in fishing effort.  相似文献   
118.
Pilot-scale combustion is required to treat arsenic-enriched biomass in China. CaO addition to arsenic-enriched biomass reduces arsenic emission. CaO captures arsenic via chemical adsorption to form Ca3(AsO4)2. Large quantities of contaminated biomass due to phytoremediation were disposed through combustion in low-income rural regions of China. This process provided a solution to reduce waste volume and disposal cost. Pilot-scale combustion trials were conducted for in site disposal at phytoremediation sites. The reaction mechanism of arsenic capture during pilot-scale combustion should be determined to control the arsenic emission in flue gas. This study investigated three Pteris vittata L. biomass with a disposal capacity of 600 kg/d and different arsenic concentrations from three sites in China. The arsenic concentration in flue gas was greater than that of the national standard in the trial with no emission control, and the arsenic concentration in biomass was 486 mg/kg. CaO addition notably reduced arsenic emission in flue gas, and absorption was efficient when CaO was mixed with biomass at 10% of the total weight. For the trial with 10% CaO addition, arsenic recovery from ash reached 76%, which is an ~8-fold increase compared with the control. Synchrotron radiation analysis confirmed that calcium arsenate is the dominant reaction product.  相似文献   
119.
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   
120.
对工业含铬废水、铬渣处理的新方法和综合利用的新思路   总被引:1,自引:0,他引:1  
本文以可靠的数据和化学原理,针对工业铬渣和含铬废水的实际情况提出处理的新方法和新思路,并应用于实践.  相似文献   
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