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231.
介绍了NID脱硫技术在410 t/h燃煤锅炉与气动脱硫技术在220 t/h水煤浆锅炉上的应用情况,比较分析了两种脱硫装置的运行成本,并提出成本控制建议.  相似文献   
232.
Urban green land compensation plays an important role in county development, ecological environment management and many other fields. The concept, methods and principles of urban green land are introduced in this paper. According to the pay fee method, the value and ecological function of various types of urban green land were analyzed. The cost-benefit analysis method (CBAM) was used to estimate different external diseconomy benefits caused by green land loss. The authors applied CBAM to estimate such benefits in the case of Shanghai, China, and calculated the actual compensation value for green land. Results indicated that in 2002, the compensation value for the green land of Shanghai was RMB 8.58 × 105 Yuan/hm2. Translated from Urban Environment & Urban Ecology, 2006, 19(3): 4–6, 11 [译自: 城市环境与城市生态]  相似文献   
233.
处理印染废水的厌氧-好氧系统技术经济分析   总被引:1,自引:0,他引:1  
对印染废水采用厌氧-好氧(A/O)处理系统与好氧处理系统的实际运行数据进行数理统计与回归运算,建立两种系统的费用函数.着重对A/O处理系统的基建投资、占地面积、电耗及运行成本等技术经济指标进行分析,并与好氧处理系统作比较,以供工程技术人员进行方案评估时参考.  相似文献   
234.
Implementing service-based chemical procurement: lessons and results   总被引:2,自引:0,他引:2  
Chemical use reduction is strongly desirable for environmental and public welfare reasons, and is a critical element of moving towards more sustainable consumption in the business-to-business economy. However, the fundamental economic relationship between chemical supplier and chemical customer creates supply side incentives for increased chemical use. Chemical management services (CMS) is a business model that aligns economic incentives in the chemical supplier–customer relationship towards reduced chemical use by making chemical services rather than chemical volume the basis of supplier compensation. CMS thus ‘servicizes’ the chemical supply chain and is a Product Service System with significant potential environmental benefits. CMS enjoys high penetration in the US auto and semiconductor sectors, and is emergent in other sectors. The paper synthesizes lessons learned from hands-on work with 15 chemical-using firms over 5 years in all aspects of CMS program implementation. Key points are that poor cost accounting and chemical information management form significant barriers to making, understanding and evaluating the CMS business case. The details of contractual compensation mechanisms are critical to achieving in practice the potential environmental benefits of the CMS model.  相似文献   
235.
Many proponents of disaster mitigation claim that it offers potential benefits in terms of saved lives and property far exceeding its costs. To provide evidence for this, and to justify the use of public funds, agencies involved in mitigation can use benefit–cost analysis (BCA). Such analysis, if well done, offers a testable, defensible means of evaluating and comparing projects, helps decision-makers choose between mitigation projects, and provides a means to assess the way we spend public funds. In this critical overview of the more contentious issues and latest developments in BCA, I emphasize the pragmatic choices that one can make in accordance with good practice in project evaluation.  相似文献   
236.
城镇污水处理厂运行成本分析   总被引:10,自引:0,他引:10  
对城镇污水处理厂运行成本的概念和组成进行分析和探讨,运行成本主要由人员费、动力费、维修费、药剂费和其他费用组成。以日处理量三万吨的城镇污水处理厂为例,结合实际工程经验,通过经验公式测算运行成本,其中动力费和维修费是运行成本的主要部分,占运行成本的78.6%,人员费占9.5%,药剂费7.1%,其他费用4.8%。并提出降低运行成本的相关措施,包括强化管理,定期保养设备,减低维修费用,改进运行方式和中水回用等。  相似文献   
237.
从安全运行和经济运行两方面论述了昆钢煤气系统中存在的问题,针对存在问题提出解决措施及建议。  相似文献   
238.
The RAMseS project, under the European Commission's 6th Framework Program, is dedicated to the construction and test of low-power operations based on photovoltaic power and a multipurpose electric vehicle. In the present study, the life-cycle costs and economical indices for the vehicle during its life span were assessed, compared to those of a standard internal combustion engine vehicle (ICEV). The results indicated that the life-cycle costs for the RAMseS vehicle and the ICEV are the same for a fuel unit price of 1.8 €/L. Also, the levelized cost of energy (LCE) for the RAMseS vehicle, was found to be 2.13 €/kWh, while RAMseS LCE, without EV taken into account, was shown to be 0.62 €/kWh. The RAMseS payback period (PBP) without EV taken into account was calculated to be 9 years if the value of the produced energy becomes at least 0.35 €/kWh. Vehicles that use PV systems as their power source, such as RAMseS, will be economically effective for fuel costs higher than 1.8 €/L, but considering the environmental benefits that are provided in terms of external costs, they can be considered profitable even at lower fuel costs.  相似文献   
239.
电除尘器粉尘层反电晕击穿厚度理论与试验   总被引:1,自引:0,他引:1  
为了合理地确定静电除尘器清灰振打周期,通过理论与试验方法确定静电除尘器粉尘层反电晕击穿厚度很有必要的。首先基于静电学理论导出带电粉尘层内的电量分布和电场分布数学模型,然后根据粉尘层反电晕发生条件,得出粉尘层反电晕击穿厚度的计算式,结果表明,反电晕击穿厚度是粉尘比电阻、电晕电流密度及极配的函数。通过对高比电阻不同厚度的粉尘层的反电晕击穿试验研究,结果表明,各击穿点的连线呈较连续光滑的弧线,提出了利用伏安特性曲线确定粉尘层反电晕击穿厚度的简易图解法。  相似文献   
240.
Coal-based olefin (CTO) industry as a complement of traditional petrochemical industry plays vital role in China's national economic development. However, high CO2 emission in CTO industry is one of the fatal problems to hinder its development. In this work, the carbon emission and mitigation potentials by different reduction pathways are evaluated. The economic cost is analyzed and compared as well. According to the industry development plan, the carbon emissions from China's CTO industry will attain 189.43 million ton CO2 (MtCO2) and 314.11 MtCO2 in 2020 and 2030, respectively. With the advanced technology level, the maximal carbon mitigation potential could be attained to 15.3% and 21.9% in 2020 and 2030. If the other optional mitigation ways are combined together, the carbon emission could further reduce to some extent. In general, the order of mitigation potential is followed as: feedstock alteration by natural gas > CO2 hydrogenation with renewable electricity applied > CCS technology. The mitigation cost analysis indicates that on the basis of 2015 situation, the economic penalty for feedstock alteration is the lowest, ranged between 186 and 451 CNY/tCO2, and the cost from CCS technology is ranged between 404 and 562 CNY/tCO2, which is acceptable if the CO2 enhanced oil recovery and carbon tax are considered. However, for the CO2 hydrogenation technology, the cost is extremely high and there is almost no application possibility at present.  相似文献   
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