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951.
提高垃圾焚烧电厂热能利用效率的几个途径 总被引:2,自引:0,他引:2
采用能量分析的方法,从几个侧面对垃圾焚烧发电厂热能利用效率低下的原因进行分析,提出了解决垃圾焚烧发电厂热能利用效率的途径:选择合适的炉型,降低散热损失以提高锅炉效率;对进厂垃圾进行堆酵以沥出其中水分,提高入炉垃圾低位热值;提高锅炉出口蒸汽参数,采用回热循环等措施增加蒸汽的可用能,提高系统发电效率。 相似文献
952.
论我国能源利用方式及大气污染防治 总被引:2,自引:0,他引:2
朱巧凤 《中国环境管理干部学院学报》2004,14(4):50-51,65
通过对我国能源结构和利用方式的论述,以及能源燃烧产生的主要大气污染物对环境影响定性和定量的分析,提出了相应的污染防治对策。 相似文献
953.
农业非点源污染的环境影响及防治对策 总被引:3,自引:0,他引:3
非点源污染负荷在水环境污染中所占比例日益增大,而农业生产活动又是最大的非点源污染.由于没有固定的污染源,控制非点源污染要比控制点源污染困难得多.扼要介绍了我国农业非点源污染的现状,分析了农业非点源污染的各种影响因素,讨论了农业非点源污染对水环境的影响,并针对目前农业非点源污染存在的问题,提出了污染防治对策和管理措施. 相似文献
954.
V. Sridhar Amy L. Sansone Jonathan LaMarche Tony Dubin Dennis P. Lettenmaier 《Journal of the American Water Resources Association》2004,40(1):197-213
ABSTRACT: Removal of streamside vegetation changes the energy balance of a stream, and hence its temperature. A common approach to mitigating the effects of logging on stream temperature is to require establishment of buffer zones along stream corridors. A simple energy balance model is described for prediction of stream temperature in forested headwater watersheds that allows evaluation of the performance of such measures. The model is designed for application to “worst case” or maximum annual stream temperature, under low flow conditions with maximum annual solar radiation and air temperature. Low flows are estimated via a regional regression equation with independent variables readily accessible from GIS databases. Testing of the energy balance model was performed using field data for mostly forested basins on both the west and east slopes of the Cascade Mountains, and was then evaluated using the regional equations for low flow and observed maximum reach temperatures in three different east slope Cascades catchments. A series of sensitivity analyses showed that increasing the buffer width beyond 30 meters did not significantly decrease stream temperatures, and that other vegetation parameters such as leaf area index, average tree height, and to a lesser extent streamside vegetation buffer width, more strongly affected maximum stream temperatures. 相似文献
955.
956.
国际环境制度对能源安全战略的重大影响 总被引:1,自引:0,他引:1
刘东民 《中国人口.资源与环境》2003,13(3):44-47
能源安全一直是国际政治和经济领域的重大问题。在追求可持续发展和全球化不断推进的2l世纪,国际环境制度的逐步形成为能源安全赋予了新的涵义,生态安全已经成为能源安全的重要组成部分。以保障能源供应为主要出发点的传统能源安全观逐渐向着涵盖能源供应、经济竞争力和环境质量三大要素的“综合能源安全观”的方向发展。 相似文献
957.
/ Land-based point and diffuse pollution sources in the catchment area of Lake Sapanca, Turkey, were investigated. The present and future distribution of pollution loads were evaluated in terms of nitrogen, phosphorus, biochemical oxygen demand, and pesticides. A methodology for the estimation of pollution loads was presented; most of which were based on "unit loads." Presently domestic and industrial point sources dominate over diffuse sources including fertilizers and pesticides from agricultural use, nutrient loads from forests and meadows, urban runoff, and leachates from unregulated dumps of solid wastes. For the future, the aim of the control action is to maintain the sustainability of the water quality of the lake, at least at the second class of European Community standards. Within this framework; urgent/short-term and medium/long-term control actions will be exercised. In the urgent/short-term stage, simpler and natural ways of treatment will be employed. In the medium/long-term stage an integrated collection and treatment system will be put on operation. After completion of a proposed collection system and treatment plants to handle point sources, the control of diffuse sources will be more significant. Control of diffuse sources for the abatement of further deterioration of water quality then becomes the key issue to be emphasized in the Lake Sapanca catchment area. Diffuse sources control will be achieved by dividing the catchment area into three major protection zones. Use of pesticides and fertilizers on agricultural land and all other activities within these protection zones will be accomplished according to control plans, which will be supervised by an institution established to be responsible of all the activities within the basin.KEY WORDS: Diffuse sources; Land-based pollution; Nutrients; Pesticides; Point sources; Protection zones 相似文献
958.
DDS系列煤炭自燃阻化剂实验研究 总被引:11,自引:0,他引:11
为寻找高效阻化剂以防止煤炭自热引燃,在控温炉中对DDS系列煤自燃阻化剂的阻化效果进行了实验研究,并与经前的阻化剂做了比较。实验采用烟煤作为试样,借助于著名的Frank-Kamenetskii模型,利用4,6,8和10厘米立方体阻化煤磁地60-220℃温度范围估测其氧化反应的活化能。 相似文献
959.
Eric L. Hyman 《Environmental management》1994,18(1):23-32
Fuelwood consumption in Northern Nigeria exceeds the sustainable production, and the deficit is currently met through long-distance
transport from the southern part of the country at an artificially low cost Current household fuel consumption patterns and
factors affecting stove choice are discussed. Little has been done to promote more efficient woodstoves in the region, but
prospects for stove programs are only good where fuelwood is marketed and the policy environment is conducive.
At subsidized official prices for kerosene, liquefied petroleum gas (LPG), and electricity, wood is more expensive on a net
usable heat basis, but the high capital cost of stoves for these fuels prevents many households from switching. Moreover,
these fuels are often only available at much higher parallel market prices, which result in wood being the less expensive
choice. There is little prospect for substitution of coal, solar cookers, or biogas digesters. 相似文献
960.
Martin M. Karpiscak Richard G. Brittain Kennith E. Foster 《Journal of the American Water Resources Association》1994,30(2):329-334
ABSTRACT: In May 1993, a single-family home and adjoining information center opened to the public at the Desert Botanical Garden in Phoenix, Arizona. Desert House is designed as an example of what can be achieved today using available technology to improve residential water and energy efficiency. The home is expected to reduce water and energy use by 40 percent compared with that for the typical three-bedroom, single-family residence in the Phoenix area. Water-conserving features include: landscape design employing low-water use plants, minimum turf area, mulch around plants to reduce evaporation, and drip irrigation system; spa cover for evaporation reduction; rainwater harvesting; low-flow shower heads, faucets, and toilets; and graywater reuse system. The home will be occupied by a family and monitored for water and energy use by computer. Visitors are able to access real time water and energy use data about the home, as well as tour the information center, technical exhibits, surrounding landscape, and the home when it is open (one afternoon a week). 相似文献