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891.
系统掌握污水深度处理臭氧氧化系统的工程造价构成及其影响因素对降低其工程造价具有重要意义。详细分析了臭氧发生、臭氧投加、臭氧接触反应及臭氧尾气处理等污水深度处理臭氧氧化系统4个子系统的工程造价构成及其影响因素,结果表明:臭氧发生单元的造价所占比重最大,高达60%~70%,其次是臭氧尾气破坏设备(16%~18%)和臭氧投加单元(12%~15%),臭氧接触反应设备的造价所占比重最小,约为3%~5%。影响臭氧氧化系统工程造价的主要因素除处理规模外,还有臭氧投加量、臭氧气体浓度及水力停留时间等工艺参数,其中臭氧投加量和臭氧气体浓度的影响较大。在达到处理要求的情况下,提高臭氧利用率、降低臭氧投加量以及升高臭氧气体浓度,是有效降低臭氧氧化系统工程造价的关键。 相似文献
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本文对建立符合国情的光污染防治体系提出相关建议。首先阐述了光污染的概况;然后对国内外光污染防治的立法现状进行研究和探讨;最后提出具体的立法构想。与欧美和日本等发达国家相比,我国的光污染防治工作才刚起步,关于光污染防治的环境立法还是空白,对光污染防治的系统性研究处于初始阶段。以经济、生态的可持续发展为指导思想,采用符合国情的立法模式,修订《中华人民共和国环境保护法》,制定光污染防治单行法《光污染防治法》,制定光环境质量标准和排放标准,建立光污染防治体系,全面防治光污染。 相似文献
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装备试验分析研究与管理监督 总被引:1,自引:1,他引:0
装备试验种类多、任务重,实际工作中存在许多模糊认识与做法。从试验的概念入手,理清、辨析了几种重要试验,分析研究了各种试验的特点,给出了具有实践应用意义上的试验原理、程序和方法,在此基础上对试验进行了相应的管理与监督。 相似文献
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Abstract It is difficult to realize the transformation from traditional economy industrial system to circular economy industrial system. Regarding primary raw materials as the indicators, the industrial system has been specified according to the divergence among the indicators and the circular utilization modes. In comparison with the association among industrial systems, the relationship among industrial sub-systems is named as industrial cross-linking in this paper. The industrial system which could completely utilize and recycle the indicators should be increased and strengthened, and the circular economy industrial system with complete industrial association and industrial cross-linking should also be constructed. Taking the development of circular agricultural system basing on the traditional agricultural system as an example, the traditional agricultural products are regarded as the indicators which have been divided into foodstuff and crop straws which are used to produce food and articles for use, like fertilizer, energy and papers etc. The way to construct the circular agricultural industrial system is to increase the industrial systems that could utilize the products generated from crop straws, feces and other castoffs and transform the wastewater and other trucks into environmental friendly products. It has also been pointed out that the construction of circular economy industrial system is conducive to the foundation of circular industrial economics and the establishment of the construction layout of circular economy and the application schemes. Suggestions to the theoretical and practical work of the next step have also been brought forward in this paper. 相似文献
900.
《International Journal of Sustainable Engineering》2013,6(3):235-243
The numerous buildings that currently require thermal rehabilitation in Romania means that substantial resources and a large number of competent people are required to carry out surveys and energy audits. However, commercial energy balance software is mostly unaffordable for those organisations involved in this process. This paper describes an energy balance programme – ENEFControl – developed to be a rapid, low cost, local tool able to assist in the choice of energy efficient solutions for buildings. To test the software, thermal and energy analyses were carried out on a 1970s built apartment block in Transylvania. Based on these analyses, three constructive scenarios were proposed for thermal rehabilitation. Compared to the performance of the analysed building, the thermal and energy performance of the retrofitted building in all three scenarios significantly improved. Since European Union accession in 2007, rapidly rising energy costs have affected the Romanian population. ENEFControl offers Romanian engineers and architects an opportunity to speed up the rehabilitation programme of buildings without the need for more expensive expertise and tools. 相似文献