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This paper describes a new procedure for real-time fusion of ballistic missile track data from multiple sensors of varying phenomenologies and update rates. This method can add value to missile defense systems by providing enhanced missile position and velocity information for warning and handover, using only position data from any number of existing sensors. This procedure is based on very minimal assumptions, making it broadly applicable to many ballistic estimation situations. >

The fluidized-bed combustion of coal is finding increasing applications in industry. By employing heat exchange surfaces located in and above the fluidized bed, it is possible to generate hot water, steam or hot gas which can be used for a range of heating and process applications. For some types of combustor design, it has been observed that unacceptably high rates of metal wastage can occur on heat exchanger surfaces which come into contact with the fluidized bed. The reason why only some units exhibit wastage is unclear and is probably masked by the wide range of operating conditions and boiler designs employed. Additionally, the precise wastage mechanism is unknown; however, it is widely believed that the wearing action of the fluidized bed on metallic surfaces is largely responsible. Whether wear occurs as a result of erosion and/or abrasion, and what role is played by corrosion, is open to question. In an attempt to resolve these issues, the metallographic nature of heat exchanger surfaces removed from a number of fluidized-bed combustors, some of which have suffered wear, has been studied using microscopic analysis. Also, laboratory-based experiments have been devised in order to simulate the type of wastage experienced in industrial units. A laboratory rig has been constructed, which allows erosion tests to be performed at low particle velocities and at elevated temperatures. Erosion tests at a low velocity and at ambient temperature are reported. Erosion rates and morphologies produced in the laboratory are compared with those observed in commercial fluidized-bed combustors. Areas of future work are also identified.

The influence of operating conditions in a coal fired fluidized bed combustor on the rate of fireside corrosion of air cooled heat exchanger tubes, with metal temperatures in the range 540/sup 0/C to 900/sup 0/C, has been investigated. Four 250 hour tests were carried out on a 0.3 m square atmospheric pressure fluidized bed combustor operating with a fluidizing velocity of 0.9 ms/sup -1/, 10 to 20% excess air and bed temperatures of 850/sup 0/C and 900/sup 0/C. The feed coal was Illinois No. 6 which was used both with and without the addition of limestones to suppress the emission of sulfur oxides. A test without the addition of limestone showed very little corrosive attack of any metal components. Tests with the addition of limestone showed a range of corrosive attack. In general, where different alloy types were exposed at the same metal temperature, the iron based austenitic steels showed a better corrosion resistance than the nickel based alloys. This result strongly supports the model for the corrosion which has been developed as a result of the earlier investigations. This model postulates that local regions of low oxygen activity exist in the system, and, in the presence of calcium sulfate,more » these result in the generation of high local sulfur activities. The combination of low oxygen and high sulfur activities leads to sulfidation of sensitive alloys.« less

When comparing coal transportation with electric transmission as a means of delivering electric power, it is desirable to compare entire energy systems rather than just the transportation/transmission components because the requirements of each option may affect the requirements of other energy system components. PNL's assessment consists of two parts. The first part, which is the subject of this document, is a detailed description of the technical, cost, resource and environmental characteristics of each system component and technologies available for these components. The second part is a computer-based model that PNL has developed to simulate construction and operation of alternative system configurations and to compare the performance of these systems under a variety of economic and technical conditions. This document consists of six chapters and two appendices. A more thorough description of coal-based electric energy systems is presented in the Introduction and Chapter 1. Each of the subsequent chapters describes technologies for five system components: Western coal resources (Chapter 2), coal transportation (Chapter 3), coal gasification and gas transmission (Chapter 4), and electric power transmission (Chapter 6).

Water may be a constraint on the expanded development of coal resources in the semi-arid western United States. Water allocation in the West has been determined by the appropriative rights doctrine which allows perpetual use of water sources by those who first claim it for beneficial purposes. This has had the effect of placing a dominative interest in water allocation in one economic sector: agriculture. New water sources are available to coal producers but political and economic problems must be overcome. Water is required by every phase of coal development. Mines use water for dust control and land reclamation. Coal slurry pipelines would use water as a transport medium. Steam electric power plants use water for cooling, cleaning, and in the boiler. Coal gasification plants would use water for cooling, cleaning, and as a material input. In addition to these direct uses of water by coal development, the people who build and operate the development demand water for domestic and recreational purposes. The quantity of water required for a given element of a coal development is site specific and dependent on many factors. The available literature cites a range of estimates of the amount of water required for each typemore » of development. The width of this range seems related to the stage of development of the particular technology. Estimates of water requirements for various schemes to provide an average electrical load of 9 GWe to a load center 1000 miles from western mines are shown in Table 5.« less

Manufacturers of irrigation equipment perform research and development in an effort to improve or maintain their position in a very competitive market. The market forces and conditions that create the intense competition and provide incentive for invention are described. Particular emphasis is placed on the market force of increased energy costs, but the analysis is developed from the perspective that energy is but one of many inputs to agricultural production. The analysis is based upon published literature, patent activity profiles, microeconomic theory, and conversations with many representatives of the irrigation industry. The published literature provides an understanding of the historical development of irrigation technology, a description of the industry's structure, and various data, which were important for the quantitative analyses. The patent activity profiles, obtained from the US Patent Office, provided details of patent activity within the irrigation industry over the past decade. Microeconomic theory was used to estimate industry-wide research and development expenditures on energy-conserving products. The results of these analyses were then compared with the insights gained from conversations with the industry representatives.

Background information is presented on the characteristics of liquid wastes and the available disposal options. Regulations that may directly or indirectly influence liquid waste disposal are reviewed. An assessment of the available wastewater-treatment systems is provided. A case study of expected liquid-waste-treatment and disposal costs is summarized. (MHR)