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1.
Most of the two billion tonnes of limestone consumed annually is used either as the basic raw material in the manufacture of cement or as flux input in the metallurgical industries. Of the total flux, 90% is used by the steel industry. The cement industry needs limestone in a finely pulverized form, whereas the steel industry uses it in lump form, with the lumps not less than 12 mm in size. The exploitation of limestone as flux for the steel industry must be scientifically planned. This article covers the methodology of planning, incorporating the study of the detailed status of the resource inventory, demand for limestone, exploration of new deposits, and calculating and manipulating the costs of production, transport and development of each project to match the demand pattern of steel plants. A computer was used for the optimization of supplies and their selection on planning horizons.  相似文献   

2.
The circular economy is an essential component of China's sustainable development. To promote the recycling of end-of-life products, the government has adopted various policies. Steel scrap is an important resource for steelmaking. Yet, the Chinese iron and steel industry uses less scrap to produce new steel compared to other large steelmaking countries. This article examines the reasons, why steel recycling is still relatively weak in China and what measures the government takes to improve the situation. We found that limited availability of scrap, high scrap prices, inadequate steelmaking capacities, industry fragmentation and unclear responsibilities for manufacturers are the main obstacles for steel recycling in China. The government is trying to improve steel recycling through tax incentives, import facilitation, support for supply, industry reorganization, and recycling parks, but with modest results.  相似文献   

3.
Closed-loop recycling of steel in automobiles is particularly difficult because of the low tolerance for impurities and the use of composites of various types of steel products. Technologies that reduce impurities or increase impurity tolerance must be developed and introduced to the steel recycling system at the appropriate time. This study evaluated the feasibility of closed-loop recycling in the automobile industry in China. Material pinch analysis combined with dynamic modeling of the life cycle of steel sheets used in the manufacture of automobiles was employed to estimate the amount of steel sheet scrap available for closed-loop recycling and the amount of copper contamination in the scrap. The results indicate that by 2050, more than half of the old steel sheet scrap generated annually will have to be down-cycled because of its high copper contamination. However, scenario analyses of three types of technologies for mitigating the problem of copper contamination showed the potential for increasing the amount of old scrap used in closed-loop recycling. In particular, improving copper tolerance in the steel production process could be effective both now and in 2050.  相似文献   

4.
To establish a sustainable society, it is necessary to understand the flows and stocks of materials. However, traditional material flow analysis requires large quantities of data relating to the consumption and trade of materials in the past and the lifetime distributions of end use. To overcome the problem that such data may not be available, we have proposed using nighttime light images to estimate the in-use stocks of materials in countries for which the data are unavailable. In the previous study, in-use steel stock for civil engineering and building in 2006 was estimated using nighttime light images. However, several aspects of the methodology must be improved, and time-series analyses using nighttime light images have not yet been performed. Therefore, in this study, we improved the estimation of in-use steel stock by using new geological information (i.e., LandScan population distribution data) and correcting the pixel area. We prepared radiance-calibrated nighttime light data for 2006 and 2010 and conducted time-series analyses of the in-use steel stock using the nighttime light data. The in-use steel stock for civil engineering and building in 2010 was found to amount to approximately 11.3 Gt, which was approximately 21% higher than that in 2006.  相似文献   

5.
2009年2月,国务院发布《废弃电器电子产品回收处理管理条例》,成为我国废弃电器电子产品回收处理的纲领性文件。在《废弃电器电子产品处理目录(第一批)》中,明确将电视机、电冰箱、洗衣机、房间空调器、微型计算机等5种产品纳入第一批目录。同时,为了为了能够及时、客观地与经济发展、技术进步以及电器电子产品行业的发展变化等相适应,《目录》管理委员会起草了《制订和调整废弃电器电子产品处理目录的若干规定》,明确随着经济发展变化及电子产品废弃形势调整电器电子产品处理目录的原则。废弃电池在近几年来在我国增长速度很大,将来的管理形势十分紧迫。本文在此分析我国几种废弃电池(铅酸电池、镍氢电池及锂电池)的产生量、再生处理处置情况及管理政策导向。并在目录一批筛选原则的基础上利用权重分析法,筛选评估废弃电池能否进入废弃电器电子产品处理目录(第二批)管理的可能,研究显示铅酸电池已具备进入管理目录的资质。  相似文献   

6.
To improve the efficiency of water use and reuse, a digitalized water network system was implemented in a steel industrial complex. The system consisted of four parts: online instrument and sensing devices, programmable logic controller, data communication network and control center based on expert knowledge. The system achieved real-time monitoring, diagnosis, and early warning of cooling water system using data collected inline, and enabled data connectivity and transmission of self-developed software applications on personal computer. This research used a steel enterprise as a case study. After the analysis of its cooling water system and water-saving potential using water balance test, a digitalized water network was evaluated and implemented, and we believe this network can be suitable for steel industry in general.  相似文献   

7.
Material flow analysis (MFA) is an evaluation technique that systematically identifies the flows and stocks of materials within predefined spatial and temporal boundaries. In this paper, the steel resources in Korea are investigated using dynamic MFA. Iron ore and steel scrap are added as raw material components during the production processes of steel, which is then used in a variety of product groups such as construction products, transportation equipment, machinery/metal products, electrical/electronic devices, and other products through fabrication and manufacturing processes. When such product groups are discarded, they are either recycled or landfilled. With consideration for the lifetimes of various product groups in conjunction with steel resource flows in Korea, dynamic MFA is conducted on the flows of steel stock change and annual scrap generation. By 2020, these two flows are expected to increase by as much as 40% and 30%, respectively, compared to 2008, with transportation equipment, in particular, envisaged to experience high growth. At the current recycling rate, however, it will be hard to meet future scrap demand. According to the scenario analysis, 100% of this future scrap demand can be supplied domestically if the recycling rate is increased to over 70% for all product groups, except construction products and transportation equipment, which already have high recycling rates. By 2020, the reduction in scrap importation costs is projected to offer a financial gain of 2.3 billion dollars.  相似文献   

8.
An iron resource efficiency is proposed to define a measure of the natural iron resources saved in the steel manufacturing process. A simplified iron flow diagram is presented for the steel manufacturing process. The influences of various deviations in iron flow from the simplified iron flow diagram on iron resource efficiency are analyzed. The relationships between iron resource efficiency of unit processes and the final product are also discussed. As an example, data from a steel plant are used to analyze the influence of iron flow on its iron resource efficiency of finial product in the steel manufacturing process, the influence of iron resource efficiency of unit process on iron resource efficiency of the final product, and give some measures to improve the iron resource efficiency of the steel manufacturing process.  相似文献   

9.
湿热环境应力下产品失效机理分析   总被引:2,自引:0,他引:2  
马志宏  李金国 《环境技术》2006,24(5):31-33,44
阐述了湿热环境下产品的失效模式,分析了在湿热环境应力下产品功能失效的原因,指出了产品一般都会受到湿度与温度的综合影响,产品的各种劣化效应往往是产品表面受潮和体积受潮两种现象所造成的,并针对性地提出了对产品进行有效防护的方法.  相似文献   

10.
Fresh water has become a very topical, emotive and sensitive issue in Zimbabwe following the recent continued droughts in conjunction with lack of finance to expand water resources development. Heated debates have arisen over the availability, allocation, distribution, disbursement and conservation of this precious resource. A great deal of inefficiency has also resulted from Government Ministries or Departments playing all the roles, from policymaking to supply operations. Government authorities often make the mistake of controlling day-to-day management of water and sewage services. In fact, greater accountability results when Government authorities focus on policymaking, establishing regulatory regimes that provide incentives for achieving goals and sanctions for serious failures, while giving sufficient autonomy to entities responsible for investment and operations to control outcomes. It is becoming more and more evident throughout the world that provision of water, as opposed to the planning and allocation of the water resource, should be handled by commercial undertakers. Indeed, Zimbabwe and its neighbours are currently involved with changing the status of their water departments to corporate entities; Botswana, Malawi, Namibia, South Africa and Zambia have already commercialised or are currently in the process of commercialising their freshwater supply services.  相似文献   

11.
Targets to cut 2050 CO2 emissions in the steel and aluminium sectors by 50%, whilst demand is expected to double, cannot be met by energy efficiency measures alone, so options that reduce total demand for liquid metal production must also be considered. Such reductions could occur through reduced demand for final goods (for instance by life extension), reduced demand for material use in each product (for instance by lightweight design) or reduced demand for material to make existing products. The last option, improving the yield of manufacturing processes from liquid metal to final product, is attractive in being invisible to the final customer, but has had little attention to date. Accordingly this paper aims to provide an estimate of the potential to make existing products with less liquid metal production.Yield ratios have been measured for five case study products, through a series of detailed factory visits, along each supply chain. The results of these studies, presented on graphs of cumulative energy against yield, demonstrate how the embodied energy in final products may be up to 15 times greater than the energy required to make liquid metal, due to yield losses. A top-down evaluation of the global flows of steel and aluminium showed that 26% of liquid steel and 41% of liquid aluminium produced does not make it into final products, but is diverted as process scrap and recycled. Reducing scrap substitutes production by recycling and could reduce total energy use by 17% and 6% and total CO2 emissions by 16% and 7% for the steel and aluminium industries respectively, using forming and fabrication energy values from the case studies. The abatement potential of process scrap elimination is similar in magnitude to worldwide implementation of best available standards of energy efficiency and demonstrates how decreasing the recycled content may sometimes result in emission reductions.Evidence from the case studies suggests that whilst most companies are aware of their own yield ratios, few, if any, are fully aware of cumulative losses along their whole supply chain. Addressing yield losses requires this awareness to motivate collaborative approaches to improvement.  相似文献   

12.
温度影响造成产品的故障是各种环境中最多的,本文对温度环境下产品失效机理进行了分析,并针对性地提出了对产品进行有效防护的方法.  相似文献   

13.
This study investigates how environmental strategies change over time. We submit evidence from the US steel industry that firms have modified their strategies over time. We offer that US industry passed through three stages--cost minimization, cost-effective compliance, and beneficial environmental controls. We compare typologies of environmental strategies and choose that of C. Oliver as the most appropriate. We investigate how environmental strategies in the steel industry changed over time a 4-year period. We offer that a further understanding of Oliver's strategies may increase understanding of the relationship between business and government on environmental issues. One over-arching problem in our field is the need to adequately operationalize how firms change strategies and pass through different stages. We hope that our study will help future researchers and practitioners better articulate the concepts of environmental strategies over time. Our study focused on the steel industry in the United States. We chose the US steel industry as one of the major environmental actors in the United States. The United States Environmental Protection Agency ranks the iron and steel industry as the largest industrial source of toxic environmental contamination. We encourage researchers to evaluate and test our methodology and findings in other contexts--both in other nations and different industries.  相似文献   

14.
Construction industry consumes about half of all material resources taken from nature, and generates a large portion of waste to landfill. A way of tackling negative environmental impacts impending from continuous material extraction and waste generation is the use of recycled materials for construction projects. However, the use of recycled materials is yet to become a commonplace in construction industry. This study evaluates the factors hampering the use of recycled products in UK construction industry as well as strategies that could be adopted to enhance its use in the industry. In order to identify the impediments and critical strategies, a two-fold methodical approach was used. An unstructured interview preceded a quantitative questionnaire survey which was used to elicit broader industry practitioners’ opinion.The study shows that designers rarely specify recycled products. This is due to lack of adequate information about quality and market availability of the products, negative perception from clients, and unexpectedly high cost of the products, despite its perceived low quality. The study suggests that a number of strategies could be adopted to promote the use of the products. These include allocation of points to the use of recycled products in sustainable design appraisal tools, governments legislative measures, improved collaboration between designers, contractors and materials suppliers, contractors involvement at earlier stage of design, improved education of the professionals about the products, and the use of tax break to influence the cost of the products. The findings of this study would therefore help policy makers, manufacturers and construction professionals to identify the factors hampering the use of recycled products for construction projects as well as the strategies that could be adopted in order to create market for the products.  相似文献   

15.
Summary While there is a burgeoning literature on national approaches to environmental policy and programmes, much less interest thus far has been shown in the role of local government. However, the State of Victoria in Australia, in the period 1988–1990, took a world lead in encouraging local municipalities to formulate Local Conservation Strategies (LCSs) with a high level of citizen input. The paper places this programme initiative in context and reports on the results of consultations and workshops with local Municipal Conservation Officers who have been in the front line in terms of developing and implementing LCSs in that State. In particular, the paper explores the process of LCS formulation and highlights some of the benefits and problems with the programme so far.Dr David Mercer is a Senior Lecturer in the Department of Geography and Environmental Science at Monash University, Melbourne. His major research interest is Australian environmental policy. Dr Meg Keen's research interests are in environmental education and management.  相似文献   

16.
This paper has two main objectives: (1) to discuss the basics of component modeling and its conceptual implications in environmental modeling; and (2) based on this discussion, to present a component-based design to support the simulation of wildlife movements. Components are independently developed, ready-to-use software units that can be assembled together to construct a modeling system. The conceptual implications of component modeling for the representation of environmental phenomena are discussed. A comparison is made between these conceptual implications and those of the more familiar object-oriented approach. A component-based design for supporting the simulation of wildlife movements is presented in this paper in order to illustrate how component modeling can be used to support the spatial representation of ecological phenomena and processes.  相似文献   

17.
In developing countries, the recycling of municipal solid waste (MSW) as an alternative to the traditional MSW management requires an economic sustainability valuation. From this perspective, the estimation of demand for recycling is crucial. In this paper, we study the case of recycling MSW in Santiago, Chile. We estimate the relation between the monthly amount of MSW separated voluntarily from apartments located in Santiago and the monthly price required to participate in a municipal recycling program. We consider the transference of the municipal cost savings to the owners of the apartments due to the amount of MSW separated for recycling, which is not collected and deposited in the current MSW system. For the estimation, we use concepts from environmental economics and psychology, analyzing the operation and municipal costs incurred by current MSW management and designing and applying a survey based on a contingent valuation method (CVM) approach. The results indicate that the percentage of MSW separated for recycling varies between a 27.98% and 33.18%, that only four MSW types are affected by a variation of the monthly price, and that a reduction of monthly collection trips in the current MSW system from 24 to 18 can be obtained. Additionally, we discuss a number of methodological aspects to be considered in a similar study of valuation of recycling in developing countries. Our conclusion is that Santiago has favorable conditions for the implementation of a recycling program as an alternative to the current MSW system.  相似文献   

18.
王秀兰 《四川环境》2001,20(1):75-75
根据测定BOD5所须具备条件,经过理论推导,得出水样稀释倍数的大致范围,对多种工业废水测试证,表明方法简便易行。  相似文献   

19.
20.
研究絮凝剂硫酸铝Al2(SO4)3与助凝剂聚丙烯酰胺(PAM)联合处理生活污水的效果。研究表明:Al2(SO4)3与PAM联用比单独用Al2(SO4)3处理生活污水效果更好;Al2(SO4)3 PAM对生活污水CODCr和浊度具有良好的去除能力;当投加1:1的50mg/L的Al2(SO4)3 0.5mg/L的PAM,调节水体pH=7时,处理效果最理想,CODCr去除率可达95.8%,浊度去除率可达97.5%。为复合絮凝剂Al2(SO4)3 PAM处理生活污水的应用提供了有价值的参考依据。  相似文献   

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