Francis C. McMichael

A Chinese cokemaking process-flow model for energy and environmental analyses

Abstract The purpose of this paper is to describe the design of a process-flow model that will improve our understanding of the industrial energy use, efficiency, and pollution in the cokemaking sector in the Peoples Republic of China (China). We use a modified version of the input–output process model (IOPM), developed by Lin and Polenske. By modifying the design of the IOPM model for use in the cokemaking sector, we have made three key contributions. First, the end result of our design is a generic energy process-flow model that can be easily adapted for use in conducting energy and environmental analyses of cokemaking in China and other countries as well as examining other industrial processes in other sectors. Second, as we constructed our design framework, we have identified the key differences in energy use and pollution generation among three generic cokemaking technologies in China. Third, we have determined the crucial issues, such as changes in iron and steel making technologies, plant location, and world coal and coke trade, that may affect the cokemaking sector in China in the next decade. Our research is a micro-level examination of the production processes and input–output structure of three alternative types of cokemaking technologies (modified indigenous, small machinery, and nonrecovery) in use in Shanxi Province, China, in the year 2000.

Reducing environmental burdens of solid-state lighting through end-of-life design

With 20% of US electricity used for lighting, energy efficient solid-state lighting technology could have significant benefits. While energy efficiency in use is important, the life cycle cost, energy and environmental impacts of light-emitting diode (LED) solid-state lighting could be reduced by reusing, remanufacturing or recycling components of the end products. Design decisions at this time for the nascent technology can reduce material and manufacturing burdens by considering the ease of disassembly, potential for remanufacturing, and recovery of parts and materials for reuse and recycling. We use teardowns of three commercial solid-state lighting products designed to fit in conventional Edison light bulb sockets to analyze potential end-of-life reuse strategies for solid-state lighting and recommend strategies for the industry. Current lamp designs would benefit from standardization of part connections to facilitate disassembly and remanufacturing of components, and fewer material types in structural pieces to maximize homogeneous materials recovery. The lighting industry should also start now to develop an effective product take-back system for collecting future end-of-life products.

Recycling batteries

Hundreds of millions of large and billions of small batteries are used up annually in the service of all manner of electronic devices. Until recently, the tons of toxic materials in these batteries would wind up in the garbage, but the systematic collection and recycling of spent batteries is growing. Effective recycling involves changes at all stages of battery life, starting with production. Manufacturers should attempt to use recycled materials themselves, label batteries clearly for easier sorting, and ensure that batteries can be effectively recycled. Consumers need to take part in recycling programs by separating batteries from other wastes-doing so after their disposal in general municipal solid wastes is quite expensive per ton of battery material recovered. Retailers and shippers are needed to collect and return post-consumer batteries to recyclers. Finally, recycling plants and processes are needed for each of the various battery types and materials. The authors discuss materials management, battery design issues, systematic collection, recycling technologies, nickel and cadmium recovery, consumer cell recycling, detoxification costs, and future prospects.

Economic input/output analysis to aid life cycle assessment of electronics products

Economic input/output (EIO) analysis is a well established modelling framework for tracing the flows of inputs and outputs throughout an economy. It can aid life cycle analysis by providing a comprehensive framework for analyzing environmental costs, thereby eliminating the ad hoc boundary assumptions required in conventional life cycle analysis. We illustrate use of the EIO method with applications to electronics manufacture, including Household Refrigerators and Freezers (SIG 3632), Computers and Office Equipment (SIG 357), and Household Audio and Video Equipment (SIG 3651). The EIO provides an estimate of all direct and indirect pollution discharges associated with manufacture of these products. Our EIO model is based upon the Department of Commerce 480/spl times/480 commodity sector data and a variety of environmental impact indices, including the toxic release inventory (TRI) and energy use.

Product disposal and re-use issues for portable computer design

Portable computers including laptops, notebooks, sub-notebooks and portable digital assistants are a rapidly growing segment of the computer market. Manufacturers of portable computers have an opportunity to win public praise and to avoid censure and liability by embracing green design and sensible product disposal systems. This paper analyzes the environmental issues associated with disposal, re-use and recycling of these machines, focusing on potential design changes to alleviate environmental burdens. Portable computers can replace larger machines, resulting in lower energy use and lower overall material demand. Since the number of portable computers purchased may be as many as 100 million over the next decade, environmental concerns become increasingly important. Portable computers use batteries with toxic components, so there are disposal or recycling problems. Another significant issue in assessment of disposal and recycling processes is the expected life time of portable computers. Machine design with capability for easy upgrade can be expected to have a longer useful life. The paper uses experience gained in several generations of wearable computer designs at Carnegie Mellon University for illustration.<<ETX>>

Cross-Media Environmental Impacts of Air Pollution Regulations for a Coal-Fired Power Plant

The types and rates of pollutant emissions from a coal-fired power plant depend upon plant design, coal characteristics, and environmental control policy. In the past, air pollution regulations were often promulgated without rigorous analysis of the resulting energy penalties and secondary environmental impacts that occur in other environmental media (air, land, or water), which are counterproductive to overall environmental quality. This paper describes a Comparative Assessment Model that has been developed to consider systematically such tradeoffs for conventional and advanced coal-to-electric technologies. The model is applied to quantify the secondary (“cross-media”) environmental and resource impacts resulting from alternative air pollution control policies that reduce sulfur dioxide emissions from a 1000 MW power plant. Multimedia pollutant burdens are presented, together with the increased requirements for coal, limestone, and water that are incurred in generating a fixed net quantity of electricit...

Life-cycle environmental comparison of primary and secondary batteries

Life-cycle assessment (LCA) is used to improve the environmental performance of products over their entire life, and LCA methods are in a constant state of evolution. A quantitative model for product analysis has been developed at Carnegie Mellon. The model is based on economic input-output life-cycle analysis (EIO-LCA), a tool that allows a user to quantify direct and indirect relationships among industry sectors and associated environmental burdens during the manufacturing stage of a product. However, to study environmental effects over a products entire life, use and end-of-life impacts must also be quantified. This paper presents a hybrid LCA approach to product environmental assessment in which both EIO-LCA and a conventional LCA approach are applied to comparing the total environmental impacts of primary and rechargeable batteries. We find that through the manufacturing stage, the environmental impact of primary batteries is greater than that of storage batteries. Resource use and associated impacts after manufacturing can be partially quantified at present.

A characterization and critical discussion of models and their use in environmental policy

Formal models, most of them implemented with computers, play a critically important role in the development, implementation and enforcement of environmental regulatory policy. As in the social sciences, some of these models serve as research tools which are useful in developing and testing theoretical insight. But a large set of models are used directly in the day-to-day processes of impact assessment, policy-formulation, and most importantly, regulatory enforcement.This paper is not a systematic literature review of models used in environmental impact assessment. Such a review would require a book-length manuscript and would probably not serve the needs of most readers of Policy Sciences. Instead we construct a conceptual framework for classifying and thinking about environmental impact assessment models. We discuss the major model types and attempt to identify and explore some of their limitations and problems, particularly as these models relate to the development, implementation and enforcement of environmental regulatory policy. We summarize the major policy approaches to environmental control and talk very briefly about how models are used and misused in the development and implementation of environmental policy.Finally, we attempt to identify and discuss areas in this field where we believe that policy-oriented social science researchers might make important future contributions.

Environmental legacy: the impact of the manufactured gas industry in the United States

Levels of concern over the air and water impacts of U.S. industrial wastes have existed for over a century. A focus on land contamination is a more recent development but also has earlier antecedents. Air, water, and land pollution were a matter of societal concern, even though they were not necessarily identified as “environmental” effects, and information about them can be found in a variety of reports and court cases. This paper will examine the pollution effects of the manufactured gas industry—an industry that was widely distributed in cities and towns throughout the nation in the period from approximately 1825–1950.

International environmental performance measurement in the electronics industry

The electronics industry is under increasing pressure to reduce its environmental impact. Assemblers demand that component manufacturers document their environmental performance. Performance measures are needed to sort out good from bad environmental performance and practices. We present an approach to characterize the environmental burdens associated with materials, products and processes based on material use and environmental discharge data from manufacturing facilities. Each chemical is weighted by its toxicity, a first order approximation to the health burden on the population. We illustrate this method with a time trend analysis for the electronics industry, using data from the US Toxics Release Inventory (TRI) and the Census of Manufacturers. We find that the sectors environmental emissions are showing a downward trend. Comparable data availability in other countries (e.g., Canada and the Netherlands) are discussed. We examine the possibility of international environmental performance measurement and benchmarking using discharge data from different countries. The limitations of the approach are mentioned. Our indices provide information to electronics firms in making decisions about environmental control investments and plant performance. They facilitate internal and external benchmarking and allow for better environmental information about the industry.