Power Company's Plant Research Articles

System Oriented Plant Maintenance

Nuclear power company plant maintenance has been conservative since it was born. Before we adopted DREAMS system, most of PM documents were handled with paperwork and we spent much time to perform plant maintenance. Last year KHNP constructed and implemented the computerized PM system, which was part of SAP system named DREAMS, and it made KHNP cut down expenses, save time, decrease trouble and optimize work intervals. To make PM system much better, we are trying to import equipment reliability process and we have a plan to initiate it within a year. Therefore the purpose of this paper is not only introducing an advanced methodology of plant maintenance, but showing the optimized PM system (equipment reliability process), considering safety and cost-effectiveness simultaneously.

Development of vanadium redox flow battery for electricity storage

There is serious demand today for superior technology for load levelling placed on power generation and transmission facilities. The vanadium battery, developed by Kashima-Kita, uses vanadium compounds as an electrolyte, recovered from boiler soot in Orimulsion-fired power stations to provide a solution to this problem. This battery is eminently suitable for load levelling, being operable at room temperature and normal pressure, easily convertible to a large scale and is environmentally friendly. In September 1997, Kashima-Kita built a 200 kW×4 hour-rate battery after having built both 2 kW and 10 kW prototype units. The battery is interconnected to the company's power plant grid system and has to date achieved 650 cycle continuous operation at the rated efficiency. This success has proved that a high-efficiency heat power station system equipped with such an electricity storage battery reusing byproducts of the power plant can be commercially viable.

Southern company tests of wood/coal cofiring in pulverized coal units

Tests were conducted in June 1992 at Georgia Power Company's plant Hammond Unit 1 to evaluate the impact of cofiring wood waste with pulverized coal on plant performance. Hammond 1 is a 100 MW Babcock and Wilcox (B & W) unit fueled by pulverized coal. Over a three day period, 11 full load performance tests were conducted, five with coal and six with wood/coal mixture. A total of 125 tonnes (140 tons) (as received, 19% moisture) was burned, the wood waste a mixture of sawdust and ground tree trimming waste. Wood percentage in the fuel ranged between 9.7 and 13.5%, with an average for the cofire tests of 11.5% (all percentages by weight). At medium and high O 2 levels, boiler efficiency with wood cofiring was within 0.2-0.4% of boiler efficiency with coal alone. Mill fineness was slightly affected, as the wood particles did not grind as small as the coal particles. Coal particles experienced only a minimal effect due to the presence of the wood. Mill power increased with wood cofiring. Opacity was observed to increase with wood cofiring, the cause of which is presently under investigation. NO x emissions with wood were about the same or slightly less than with coal firing. Sulfur emissions theoretically should have been 6–7% lower with wood cofiring. This decrease was not observed because of fluctuations in the coal sulfur content.

Dynamic oscillations predicted by computer studies

During the latter part of 1988, a study was begun to review the dynamic stability performance of Georgia Power Company's Plant Scherer. The scope of the study was to identify any operating conditions that might contribute to system oscillations and to examine alternative solutions that would control these oscillations. The study was performed in several phases. The authors briefly discuss the study process which utilized two different software packages for the analysis: dynamic stability studies using time-domain software and eigenvalue analysis using frequency-domain software.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

The Impact of Climatic Extremes on Cotton Rat (Sigmodon hispidus) Populations

The impact of weather extremes was examined for cotton rat (Sigmodon hispidu-s) populations occupying an Andropogon-dominated old field and a fescue (Festuca spp.) pasture on the Piedmont of Georgia. Cotton rat abundance was greatly reduced in spring 1977 relative to the springs of 1975 and 1976. Record winter cold followed by prolonged drought in spring and summer 1977 was associated with reduced Sigmodon reproduction and an absence of the normal autumn population buildups. The old-field Sigmodon population remained depressed through March 1979, whereas the pasture population became locally extinct after September 1977. Weather-induced habitat modification also occurred in conjunction with the Sigmodon collapses. The old field experienced some Andropogon mortality and a retrogressive shift to an earlier successional stage as Solidago, Lespedeza and several other species became established in 1977. Vegetation cover in the old field became patchy as these plant species colonized the area. In contrast, plant species composition remained unchanged in the pasture despite the weather conditions. The reduction in cotton rat abundance in the pasture was associated with a sharp decline in vegetation biomass and cover through 1978. INTRODUCTION The direct effects of local climatic conditions on Sigmodon populations have been documented (Dunaway and Kaye, 1961; Fleharty et al., 1972; Glass and Slade, 1980; Sauer, 1985). In particular, the effects of cold weather on reproduction (Goertz, 1964) and nest-building (Dawson and Lang, 1973) have been examined. Exposure to long periods of subfreezing temperatures can kill cotton rats (Goertz, 1964; Dunaway and Kaye, 1961) or weaken their resistance to further climatic stresses (Sauer, 1985). Severe local climatic conditions may also reduce the available food and cover and thus exert indirect effects on Sigmodon populations. The possible impact of these indirect effects have remained largely unstudied. The Piedmont region of Georgia experienced one of the most severe winters on record during 1976-1977 (U.S. Dep. Commerce, 1973-1982), which included prolonged periods of subfreezing temperatures. The severe winter was followed by a particularly dry spring and below average rainfall for 11 months (U.S. Dep. Commerce, 19731982). The direct effects of these conditions on wild animal populations were probably severe (Robbins et al., 1986). However, in some areas the indirect effects resulting from habitat modification appeared to be even more critical. The extreme weather conditions seemed to interrupt natural successional processes and alter vegetation structure. The purpose of the present study was to determine the changes which occurred in two Sigmodon populations during this period of extreme climatic conditions. We were also interested in assessing the nature and extent of habitat modification that resulted and the possible effect of any changes on Sigmodon populations. MATERIALS AND METHODS The study was conducted on Georgia Power Company's Plant Bowen near Cartersville, Georgia. This 800-ha reservation occurs at the transition from Piedmont to Ridge 'Present address: Department of Natural Resources, Environmental Protection Division, 205 Butler Street, S.E., Suite 1154, Atlanta, Ga. 30334.

An analysis of the water-level monitoring system for a boiling-water reactor

The water-level instrumentation system is very important to the overall safety of a BWR. This system is being monitored by the Safety Parameter Display System (SPDS) that is being installed in Georgia Power Company's Plant Hatch. One of the most significant functions of the SPDS is the comparison of redundant instrument readings and formation of the best estimate of each parameter from those readings which are consistent. When comparing water-level instrument readings, it is necessary to correct the individual readings for differences between current and calibration conditions as well as for differences between calibration conditions for the multiple instruments. This paper documents the examination of the water-level instrumentation system at Plant Hatch and presents the development of the equations that were used to determine the differences between indicated and actual water levels.

A model of second-order chemical reactions in turbulent fluid — part II. Application to atmospheric plumes

The model developed in Part I to describe second order chemical reactions in turbulence is adapted for predicting the rates of chemical reactions occurring in plumes from atmospheric sources. The numerical planetary boundary layer model of Deardorff is employed to obtain the turbulence statistics required to implement the closure model in this role under unstable atmospheric conditions. A test of the model is performed by simulating the rate of nitric oxide oxidation in the near-source portion of a plume from the Potomac Electric Company's power plant at Morgantown, Maryland. The results, which agree well with observations, indicate that turbulent concentration fluctuations greatly inhibit the rate of nitric oxide conversion in the plume for a period of about 2z 1 w ∗ , where z 1 is the height of the inversion layer below which convection is confined and w ∗ is the convective velocity scale. When fluctuation effects were eliminated from the model in one particular case, the 50%-conversion time dropped from 20 minutes to about three minutes.