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There are unconventional fuels that may serve as near term major replacements for conventional mineral oil and natural gas. These include fuels from oil shale and bitumen, liquid fuels from coal, methane from methane hydrates, biofuels and the secondary fuel hydrogen. Here, these fuels will be reviewed as to their presumable stocks and life cycle wastes, emissions and inputs of natural resources. The unconventional fuels are usually characterized by a relatively poor source-to-burner energy efficiency when compared with current conventional mineral oil and gas. Apart from some varieties of hydrogen and biofuel, their life cycles are characterized by relatively large water inputs, emissions, and wastes. The unconventional...
Governmental policy options in response to increasing concern over an emerging greenhouse warming are reviewed. These will reflect differing levels of pofitical concem as understanding on the future size and impacts of the greenhouse effect evolves. High levels of concem will place emphasis on the option of limiting C02 emissions by restricting fossil fuel use. This option requires emphasis on energy efficiency and changes in energy supply, with increased use of natural gas, nuclear power or renewable energy sources. The progressive industrialization of the LDCs with the consequent growth in energy demand, may put additional pressure on developed countries to take action on this policy option.
Environmental monitoring has been an ongoing activity on the U.S. Department of Energy's Hanford Site in southeastern Washington for almost 50 years. Objectives are to detect and assess potential impacts of Site operations on air, surface and ground waters, foodstuffs, fish, wildlife, soil and vegetation. Data from monitoring effects are used to calculate the overall radiological dose to humans working onsite or residing in nearby communities. In 1989, measured Hanford Site perimeter concentrations of airborne radionuclides were below applicable guidelines. Concentrations of radionuclides and nonradiological water quality in the Columbia River were in compliance with applicable standards. Foodstuffs irrigated with...
Issues related to energy saving and pollution reduction are closely related. Their importance has increased in recent years and presents considerable academic and industrial challenges. They generally represent complex tasks of a considerable scale and comprehensive interactions. The methodology and concepts of Process Integration have been developing over last thirty years [1] and have been considerably expended to tackle these problems [2]. International conferences provide a good opportunity to review the state-of-the-art in this field. One of the most established and well known conference is PRES. The 13th Conference on “Process Integration, Modelling and Optimisation for Energy Saving and Pollution Reduction...
This study proposes a new use of Data Envelopment Analysis (DEA) to measure the operational, environmental and both-unified efficiency measures of US coal-fired power plants. The power plants produce not only desirable outputs (e.g., electricity) but also undesirable outputs (e.g., CO2 and NOx) as a result of their plant operations. A Range-Adjusted Measure (RAM) is used as an original non-radial DEA model. Then, it is reformulated for handling undesirable (bad) outputs. The proposed use of DEA models measures the environmental and unified performance of power plants under two variable alternatives (with and without CO2 emission control) in order to examine both the influence of US Clean Air Act (CAA) on the acid...
The Swedish programme for geological disposal of spent nuclear fuel is approaching major milestones in the form of permit applications for an encapsulation plant and a deep geologic repository. This paper presents an overview of the bedrock and surface modelling work that comprises a major part of the on-going site characterization in Sweden and that results in syntheses of the sites, called site descriptions. The site description incorporates descriptive models of the site and its regional setting, including the current state of the geosphere and the biosphere as well as natural processes affecting long-term evolution. The site description is intended to serve the needs of both repository engineering with respect...