WorldWideScience

Sample records for cooling tower water

  1. Hot-water cooling tower

    International Nuclear Information System (INIS)

    The covering of a cooling tower as suggested prevents the escape of steam possibly mixed with other components into the environment, thus preventing the possibility of smog formation. From the cap sealing the cooling tower on its upper side, the steam is sucked off by an external jacket-cooled pipe line by means of a ventilator. The ventilator lies in a bypass of the pipeline, thus keeping condensates developed away from the ventilator. The condensate reaches the draintank in the footing of the cooling tower through the pipeline. This drain tank also takes up the condensate developing directly in the tower. (HP)

  2. Asbestos in cooling-tower waters

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, B.A.G.

    1977-12-01

    Fill material in natural- or mechanical-draft cooling towers can be manufactured from a variety of materials, including asbestos cement or asbestos paper. To aid in the environmental impact assessment of cooling towers containing these asbestos types of fill, information on these materials was obtained from cooling-tower vendors and users. Samples of makeup, basin, and blowdown waters at a number of operating cooling towers were obtained, and identification and enumeration of asbestos in the samples were performed by transmission electron microscopy, selected-area electron diffraction, and energy-dispersive x-ray analysis. Asbestos fibers were detected in cooling-tower water at 10 of the 18 sites sampled in the study. At all but three sites, the fibers were detected in cooling-tower basin or blowdown samples, with no fibers detected in the makeup water. The fibers were identified as chrysotile at all sites except one. Concentrations were on the order of 10/sup 6/ to 10/sup 8/ fibers/liter of water, with mass concentrations between <0.1 ..mu..g/liter to 37 ..mu..g/liter. The maximum concentrations of asbestos fibers in air near ground due to drift from cooling towers were estimated (using models) to be on the order of asbestos concentrations reported for ambient air up to distances of 4 km downwind of the towers. The human health hazard due to abestos in drinking-water supplies is not clear. Based on current information, the concentrations of asbestos in natural waters after mixing with cooling-tower blowdown containing 10/sup 6/ to 10/sup 8/ fibers/liter will pose little health risk. These conclusions may need to be revised if future epidemiological studies so indicate.

  3. Cooling tower water ozonation at Southern University

    International Nuclear Information System (INIS)

    Cooling-tower water is a critical utility for many industries. In the past, inexpensive water coupled with moderate regulation of discharge water led to the neglect of the cooling tower as an energy resource. Now, with the increased cost of chemical treatment and tough EPA rules and regulations, this situation is rapidly changing. The operator of the DOE Y-12 Plant in Oak Ridge as well as many other industries are forced to develop an alternate method of water treatment. The cooling tower is one of the major elements in large energy systems. The savings accrued from a well engineered cooling tower can be a significant part of the overall energy conservation plan. During a short-term ozonation study between 1987-1988, the Y-12 Plant has been successful in eliminating the need for cooling tower treatment chemicals. However, the long-term impact was not available. Since April 1988, the ozone cooling water treatment study at the Y-12 Plant has been moved to the site at Southern University in Baton Rouge, Louisiana. The purpose of this continued study is to determine whether the use of ozonation on cooling towers is practical from an economic, technical and environmental standpoint. This paper discusses system design, operating parameter and performance testing of the ozonation system at Southern University

  4. Isolation of Legionella pneumophila from Cooling Tower Water by Filtration

    OpenAIRE

    Orrison, Leta H.; Cherry, William B.; Milan, David

    1981-01-01

    Methods are described for detection of Legionella pneumophila in cooling tower water or other water sources by direct fluorescent-antibody staining. A procedure for isolation of Legionella bacteria from water samples by guinea pig inoculation is described. Two different serogroups of L. pneumophila were isolated repeatedly from one of the cooling towers.

  5. The catalytic disinfection of cooling water in cooling tower systems

    Energy Technology Data Exchange (ETDEWEB)

    Koppe, J. [MOL Katalysatortechnik, Schkopau (Germany); Mielke, D. [Ausimont (Deutschland) GmbH (Germany); Polster, D. [AmpereDirect AG (Germany)

    2000-12-01

    The catalytic disinfection of cooling water in cooling tower systems applying the GEA-MOLCLEAN procedure is based on the combined effect of hydrogen peroxide, solid metal catalysts and microorganisms present in the cooling water. In contrast to many other disinfection treatments, no toxic or environmentally problematic substances are required. Hydrogen peroxide decomposes to oxygen and hydrogen after the disinfection reaction. For the last 18 months, this treatment has been successfully applied in the cooling system of AUSIMONT Deutschland GmbH, Bitterfeld, among other sites. The treatment employment in existing systems is, as a rule, simple and does not require particular protective measures or maintenance. The biocide and algaecide effect is limited only to the treated cooling system.

  6. Cooling towers

    International Nuclear Information System (INIS)

    This paper investigates the internal elements of the typical types of cooling towers currently used, delineates their functions and shows how to upgrade them in the real world for energy savings and profitability of operation. Before and after statistics of costs and profits obtained through optimization of colder water by engineered thermal upgrading are discussed

  7. Asbestos in cooling-tower waters. Final report

    International Nuclear Information System (INIS)

    Water discharges from cooling towers constructed with asbestos fill were found to contain chrysotile--asbestos fibers at concentrations as high as 108 fibers/liter. The major source of these fibers, appears to be the components of the towers rather than the air drawn through the towers or the makeup water taken into the towers. Suggested mechanisms for the release of chrysotile fibers from cooling-tower fill include freeze-thaw cycles and dissolution of the cement due to acidic components of the circulating water. Ash- or other material-settling ponds were found to reduce asbestos-fiber concentrations in cooling-tower effluent. The literature reviewed did not support the case for a causal relationship between adverse human health effects and drinking water containing on the order of 106 chrysotile--asbestos fibers/liter; for this and other reasons, it is not presently suggested that the use of asbestos fill be discontinued. However, caution and surveillance are dictated by the uncertainties in the epidemiological studies, the absence of evidence for a safe threshold concentration in water, and the conclusive evidence for adverse effects from occupational exposure. It is recommended that monitoring programs be carried out at sites where asbestos fill is used; data from such programs can be used to determine whether any mitigative measures should be taken. On the basis of estimates made in this study, monitoring for asbestos in drift from cooling towers does not appear to be warranted

  8. Sand filter system keeps cooling water clean; eliminates tower downtime

    Energy Technology Data Exchange (ETDEWEB)

    Phelan, M.; Hodel, A.E.

    1985-01-01

    Water circulating through a cooling tower scrubs dust and other atmospheric particulates from the air. The cooling tower at ARCO Oil and Gas Company, Plano, TX, serves a computer/data processing complex which has a 2000 ton air conditioning system, normally operating at about 70% capacity, that is required to provide temperature-humidity control for the operation of the computers and associated electronic equipment. The water is circulated by a 300 hp pump through 24'' diam pipes to chillers and other heat transfer equipment located on four floors of a six story building about 50' below the tower. The equipment must be kept in operation at all times. Any downtime for preventative maintenance must be minimized and has to be coordinated with user schedules. Normal practice has been to schedule a shutdown over a weekend about once a year and clean out the cooling tower during the downtime. It takes a crew of 4 men about 6-8 hours to clean out the system. ARCO investigated a continuous cooling tower water filtration system and decided to purchase a permanent (sand) media filtration system. The sand filter has eliminated the need for cleaning the cooling tower. Downtime for tower cleaning no longer has to be scheduled once or twice a year as it was before the filter installation. ARCO expects to be able to reduce the amount of algaecide, inhibitor and oxygen scavenger treatment through the removal of suspended and settled particulates that have added to the requirements for chemical treatment. The cooling tower system now operates as one of the cleanest in the area.

  9. Cooling tower calculations

    International Nuclear Information System (INIS)

    The problems are summed up of the dynamic calculation of cooling towers with forced and natural air draft. The quantities and relations are given characterizing the simultaneous exchange of momentum, heat and mass in evaporative water cooling by atmospheric air in the packings of cooling towers. The method of solution is clarified in the calculation of evaporation criteria and thermal characteristics of countercurrent and cross current cooling systems. The procedure is demonstrated of the calculation of cooling towers, and correction curves and the effect assessed of the operating mode at constant air number or constant outlet air volume flow on their course in ventilator cooling towers. In cooling towers with the natural air draft the flow unevenness is assessed of water and air relative to its effect on the resulting cooling efficiency of the towers. The calculation is demonstrated of thermal and resistance response curves and cooling curves of hydraulically unevenly loaded towers owing to the water flow rate parameter graded radially by 20% along the cross-section of the packing. Flow rate unevenness of air due to wind impact on the outlet air flow from the tower significantly affects the temperatures of cooled water in natural air draft cooling towers of a design with lower demands on aerodynamics, as early as at wind velocity of 2 m.s-1 as was demonstrated on a concrete example. (author). 11 figs., 10 refs

  10. Reducing water consumption of an industrial plant cooling unit using hybrid cooling tower

    International Nuclear Information System (INIS)

    Water consumption is an important problem in dry zones and poor water supply areas. For these areas use of a combination of wet and dry cooling towers (hybrid cooling) has been suggested in order to reduce water consumption. In this work, wet and dry sections of a hybrid cooling tower for the estimation of water loss was modeled. A computer code was also written to simulate such hybrid cooling tower. To test the result of this simulation, a pilot hybrid tower containing a wet tower and 12 compact air cooled heat exchangers was designed and constructed. Pilot data were compared with simulation data and a correction factor was added to the simulation. Ensuring that the simulation represents the actual data, it was applied to a real industrial case and the effect of using a dry tower on water loss reduction of this plant cooling unit was investigated. Finally feasibility study was carried out to choose the best operating conditions for the hybrid cooling tower configuration proposed for this cooling unit.

  11. Computerized engineering model for evaporative water cooling towers

    International Nuclear Information System (INIS)

    The evaporative cooling tower is often used to reject waste heat from industrial processes, especially power plants and chemical facilities. A consistent physical model for crossflow and counterflow cooling towers which imposes rigorous heat and mass balances on each increment of the tower under study is presented. Individual towers are characterized by specification of a mass evaporation rate equation. The solution algorithm allows reduction of test data, interpolation of the reduced data, and comparison of test results to design data. These capabilities can be used to evaluate acceptance tests for new towers, to monitor changes in tower performance as an aid in planning maintenance, and to predict tower performance under changed operating conditions

  12. Deuterium- and 18O-content in the cooling water of power station cooling towers

    International Nuclear Information System (INIS)

    The 0-18/0-16 and D/H isotope ratios of water from two different cooling towers were determined by mass spectrometry. The observed isotope fractionation corresponds to that known from natural evaporation or transpiration processes: cooling tower I: delta(D) = 46.8 per thousand, delta(18O) = 7.6 per thousand cooling tower II: delta(D) = 33.9 per thousand delta(18O) = 5.7 per thousand Evaluation of simple compartment models of a cooling tower and a distillation device suggests that there exists some isotope discrimination within the open trickling unit of a cooling tower analogous to that in a rectification column. In a real cooling tower, however, this effect is compensated largely by the recycling of the cooling water, resulting only in a small enrichment of the heavy isotopes. This can be understood as the result of three partial effects: 1) a fractionation in the vapor pressure equilibrium, 2) a kinetic effect due to diffusion of the water vapor into a turbulent atmosphere, and 3) an exchange effect which is proportional to relative humidity. This low enrichment of the heavy isotope excludes the technical use of cooling towers as isotope separation devices. (orig.)

  13. Calculating the evaporated water flow in a wet cooling tower

    International Nuclear Information System (INIS)

    On a cooling tower, it is necessary to determine the evaporated water flow in order to estimate the water consumption with a good accuracy according to the atmospheric conditions, and in order to know the characteristics of the plume. The evaporated flow is small compared to the circulating flow. A direct measurement is very inaccurate and cannot be used. Only calculation can give a satisfactory valuation. The two usable theories are the Merkel's one in which there are some simplifying assumptions, and the Poppe's one which is more exact. Both theories are used in the numerical code TEFERI which has been developed and is run by Electricite de France. The results obtained by each method are compared and validated by measurements made in the hot air of a cooling tower. The consequences of each hypothesis of Merkel's theory are discussed. This theory does not give the liquid water content in the plume and it under-estimates the evaporated flow all the lower the ambient temperature is. On the other hand, the Poppe's method agrees very closely with the measurements as well for the evaporated flow than for the liquid water concentration. This method is used to establish the specific consumption curves of the great nuclear plants cooling towers as well as to calculate the emission of liquid water drops in the plumes. (author). 11 refs., 9 figs

  14. On hydraulics calculation of water distribution in cooling towers

    International Nuclear Information System (INIS)

    A mathematical model is described for the hydraulics calculation of water distribution in the natural draught cooling towers for the Temelin nuclear power plant. The model allows determining the form of the mechanical energy curve along the asbestos cement pipe and the main distribution trough, the form of the pressure curve in the pipe and the form of the level in an open trough, the cross section velocities in the individual distribution network sections, and the flow through nozzles, i.e., the actual distribution over the tower surface of specific load due to cooling water. The values are suggested of coefficients for calculations of losses due to friction, of local losses, and of outlet coefficients obtained from the results of original studies and completed with literature data. The computer program is written in the Fortran 77 language. (Z.M.). 5 figs., 5 tabs., 9 refs

  15. Engineering and economic evaluation of wet/dry cooling towers for water conservation

    International Nuclear Information System (INIS)

    The results are presented of a design and cost study for wet/dry tower systems used in conjunction with 1000 MWe nuclear power plants to reject waste heat while conserving water. Design and cost information for wet/dry tower systems are presented, and these cooling system alternatives are compared with wet and dry tower systems to determine whether the wet/dry tower concept is an economically viable alternative. The wet/dry cooling tower concept investigated is one which combines physically separated wet towers and dry towers into an operational unit. In designing the wet/dry tower, a dry cooling tower is sized to carry the plant heat load at low ambient temperatures, and a separate wet tower is added to augment the heat rejection of the dry tower at higher ambient temperatures. These wet/dry towers are designed to operate with a conventional low back pressure turbine commercially available today. The component wet and dry towers are state-of-the-art designs. From this study it was concluded that: wet/dry cooling systems can be designed to provide a significant economic advantage over dry cooling yet closely matching the dry tower's ability to conserve water, a wet/dry system which saves as much as 99 percent of the make-up water required by a wet tower can maintain that economic advantage, and therefore, for power plant sites where water is in short supply, wet/dry cooling is the economic choice over dry cooling

  16. Cooling tower

    International Nuclear Information System (INIS)

    The proposal concerns the reinforcement of a cooling tower made of reinforced concrete, which has a dish-shaped supporting structure and has ribs running in the vertical direction. In order to reduce the cost for fitting the reinforcement, the dish-shaped supporting structure is made wholly or partly as an anisotropic dish. By this construction of the reinforcement (spatial grating with different thickness of beam reinforcement of vertical ribs and of the circular beams provided in the dish, site reinforcement of the areas between the beams) one achieves the anisotropy of the dish. The fixing of constructional steel mats as site reinforcement is advantageous. (UWI)

  17. Coagulation chemistries for silica removal from cooling tower water.

    Energy Technology Data Exchange (ETDEWEB)

    Nyman, May Devan; Altman, Susan Jeanne; Stewart, Tom

    2010-02-01

    The formation of silica scale is a problem for thermoelectric power generating facilities, and this study investigated the potential for removal of silica by means of chemical coagulation from source water before it is subjected to mineral concentration in cooling towers. In Phase I, a screening of many typical as well as novel coagulants was carried out using concentrated cooling tower water, with and without flocculation aids, at concentrations typical for water purification with limited results. In Phase II, it was decided that treatment of source or make up water was more appropriate, and that higher dosing with coagulants delivered promising results. In fact, the less exotic coagulants proved to be more efficacious for reasons not yet fully determined. Some analysis was made of the molecular nature of the precipitated floc, which may aid in process improvements. In Phase III, more detailed study of process conditions for aluminum chloride coagulation was undertaken. Lime-soda water softening and the precipitation of magnesium hydroxide were shown to be too limited in terms of effectiveness, speed, and energy consumption to be considered further for the present application. In Phase IV, sodium aluminate emerged as an effective coagulant for silica, and the most attractive of those tested to date because of its availability, ease of use, and low requirement for additional chemicals. Some process optimization was performed for coagulant concentration and operational pH. It is concluded that silica coagulation with simple aluminum-based agents is effective, simple, and compatible with other industrial processes.

  18. Cooling tower waste reduction

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, S.J.; Celeste, J.; Chine, R.; Scott, C.

    1998-05-01

    At Lawrence Livermore National Laboratory (LLNL), the two main cooling tower systems (central and northwest) were upgraded during the summer of 1997 to reduce the generation of hazardous waste. In 1996, these two tower systems generated approximately 135,400 lbs (61,400 kg) of hazardous sludge, which is more than 90 percent of the hazardous waste for the site annually. At both, wet decks (cascade reservoirs) were covered to block sunlight. Covering the cascade reservoirs reduced the amount of chemical conditioners (e.g. algaecide and biocide), required and in turn the amount of waste generated was reduced. Additionally, at the northwest cooling tower system, a sand filtration system was installed to allow cyclical filtering and backflushing, and new pumps, piping, and spray nozzles were installed to increase agitation. the appurtenance upgrade increased the efficiency of the cooling towers. The sand filtration system at the northwest cooling tower system enables operators to continuously maintain the cooling tower water quality without taking the towers out of service. Operational costs (including waste handling and disposal) and maintenance activities are compared for the cooling towers before and after upgrades. Additionally, the effectiveness of the sand filter system in conjunction with the wet deck covers (northwest cooling tower system), versus the cascade reservoir covers alone (south cooling tower south) is discussed. the overall expected return on investment is calculated to be in excess of 250 percent. this upgrade has been incorporated into the 1998 DOE complex-wide water conservation project being led by Sandia National Laboratory/Albuquerque.

  19. Design change of tower cooling water system for proton accelerator research center

    International Nuclear Information System (INIS)

    The Tower Cooling Water System (TC) is designed to reject the heat load generated by operating the accelerators and the utility facilities through the component cooling water (CCW) heat exchangers. The circulating water discharged from the circulating water pumps passes through the CCW heat exchangers, the Chiller condenser and the air compressor, and the heated circulating water is return to the cooling tower for the heat removal. In this study, The design of Tower Cooling Water System is changed as follows : At First, The quantity of cells is changed into six in order to operate the cooling tower accurately correspond with condition of each equipment of head loads. The fans of cooling tower are controlled by the signal of TEW installed in the latter parts of it. The type of circulation water pump is modified to centrifugal pump and debris filter system is deleted

  20. Cooling performance of solid containing water for spray assisted dry cooling towers

    International Nuclear Information System (INIS)

    Highlights: • Multicomponent discrete phase model in FLUENT is modified. • The new model is partially validated against experimental data. • Micro analysis of data obtained from SEM was performed. • Various benefits of using saline water in spray cooling are outlined. - Abstract: This article investigates the performance of saline water, compared to pure water in spray cooling and demonstrates the existence of several advantages. To simulate the crystallisation behaviour of saline water droplets, a set of modifications are made to the multicomponent discrete phase model (DPM) of ANSYS FLUENT. After validation against single droplet data, a practical spraying application with a single nozzle in a vertical flow path is studied. The results are compared with a similar case using pure water as the coolant. It is shown that using saline water for spray cooling improves cooling efficiency by 8% close to the nozzle. Furthermore, full evaporation takes place substantially earlier compared to the pure water case. The mechanism behind this phenomenon is explained. The consequence of this is a reduction of up to 30% in the distance between nozzle and the creation of a dry gas stream. This paper provides new fundamental understanding in the area of saline spray cooling, and shows that the use of saline water can lead to a number of benefits, such as reduced water costs (compared to pure fresh water), reduced infrastructure costs (more compact cooling towers), and improved cooling performance

  1. Analyzing the possibility of achieving more efficient cooling of water in the evaporative cooling towers of the Armenian NPP

    Science.gov (United States)

    Petrosyan, V. G.; Yeghoyan, E. A.

    2015-10-01

    The specific features of the service cooling water system used at the Armenian NPP and modifications made in the arrangement for supplying water to the water coolers in order to achieve more efficient cooling are presented. The mathematical model applied in carrying out the analyses is described, the use of which makes it possible to investigate the operation of parallel-connected cooling towers having different hydraulic and thermal loads. When the third standby cooling tower is put into operation (with the same flow rate of water supplied to the water coolers), the cooled water temperature is decreased by around 2-3°C in the range of atmospheric air temperatures 0-35°C. However, the introduced water distribution arrangement with a decreased spraying density has limitation on its use at negative outdoor air temperatures due to the hazard intense freezing of the fill in the cooling tower peripheral zone. The availability of standby cooling towers in the shutdown Armenian NPP power unit along with the planned full replacement of the cooling tower process equipment create good possibilities for achieving a deeper water cooling extent and better efficiency of the NPP. The present work was carried out with the aim of achieving maximally efficient use of existing possibilities and for elaborating the optimal cooling tower modernization version. Individual specific heat-andmass transfer processes in the chimney-type evaporative cooling towers are analyzed. An improved arrangement for distributing cooled water over the cooling tower spraying area (during its operation with a decreased flow rate) is proposed with the aim of cooling water to a deeper extent and preserving the possibility of using the cooling towers in winter. The main idea behind improving the existing arrangement is to exclude certain zones of the cooling tower featuring inefficient cooling from operation. The effectiveness of introducing the proposed design is proven by calculations (taking as an example the particular adopted design sizes and operating parameters). It is expected that after modernizing all four cooling towers (with increasing the total spraying area by 42%) the NPP power output will increase by more than 7 MW.

  2. Simultaneous effects of water spray and crosswind on performance of natural draft dry cooling tower

    OpenAIRE

    Ahmadikia Hossein; Soleimani Mohsen; Gholami Ehsan

    2013-01-01

    To investigate the effect of water spray and crosswind on the effectiveness of the natural draft dry cooling tower (NDDCT), a three-dimensional model has been developed. Efficiency of NDDCT is improved by water spray system at the cooling tower entrance for high ambient temperature condition with and without crosswind. The natural and forced heat convection flow inside and around the NDDCT is simulated numerically by solving the full Navier-Stokes equations in both air and water droplet...

  3. Simultaneous effects of water spray and crosswind on performance of natural draft dry cooling tower

    Directory of Open Access Journals (Sweden)

    Ahmadikia Hossein

    2013-01-01

    Full Text Available To investigate the effect of water spray and crosswind on the effectiveness of the natural draft dry cooling tower (NDDCT, a three-dimensional model has been developed. Efficiency of NDDCT is improved by water spray system at the cooling tower entrance for high ambient temperature condition with and without crosswind. The natural and forced heat convection flow inside and around the NDDCT is simulated numerically by solving the full Navier-Stokes equations in both air and water droplet phases. Comparison of the numerical results with one-dimensional analytical model and the experimental data illustrates a well-predicted heat transfer rate in the cooling tower. Applying water spray system on the cooling tower radiators enhances the cooling tower efficiency at both no wind and windy conditions. For all values of water spraying rate, NDDCTs operate most effectively at the crosswind velocity of 3m/s and as the wind speed continues to rise to more than 3 m/s up to 12 m/s, the tower efficiency will decrease by approximately 18%, based on no-wind condition. The heat transfer rate of radiator at wind velocity 10 m/s is 11.5% lower than that of the no wind condition. This value is 7.5% for water spray rate of 50kg/s.

  4. Cooling towers of electric power generation plants

    International Nuclear Information System (INIS)

    After a definition and a presentation of the aim of cooling, this paper deals with the operation principle of the main types of cooling towers. The main types of cooling towers can be classified in two categories: mechanical draft cooling towers and natural draft cooling towers. Equations governing heat transfers in wet or dry cooling towers are presented and applied to some problems such as dimensioning, or evaporated water rate-mass. Finally, criteria to choose a type of cooling tower are briefly given

  5. Cooling tower and environment

    International Nuclear Information System (INIS)

    The influence of a cooling tower on the environment, or rather the influence of the environment on the cooling tower stands presently -along with the cooling water supply - in the middle of much discussion. The literature on these questions can hardly be overlooked by the experts concerned, especially not by the power station designers and operators. The document 'Cooling Tower and Environment' is intented to give a general idea of the important publications in this field, and to inform of the present state of technology. In this, the explanations on every section make it easier to get to know the specific subject area. In addition to older standard literature, this publication contains the best-known literature of recent years up to spring 1975, including some articles written in English. Further English literature has been collected by the ZAED (KFK) and is available at the VGB-Geschaefsstelle. Furthermore, The Bundesumweltamt compiles the literature on the subject of 'Environmental protection'. On top of that, further documentation centres are listed at the end of this text. (orig.)

  6. Water vapour rises from the cooling towers for the ATLAS detector at Point 1

    CERN Multimedia

    Brice, Maximilien

    2015-01-01

    Electronics on the ATLAS detector produce heat when the experiment is running. An elaborate cooling system keeps the detector from overheating. On the surface, the warm water vapour that rises from the detector 100metres underground is clearly visible from the ATLAS cooling towers on the CERN Meyrin site in Switzerland.

  7. Water tower

    CERN Multimedia

    1970-01-01

    The water tower, being built on the highest point of the site, 460.5 m above the sea level. The tank will hold 750 m3 of water, and the tower will be topped by a knob which can serve as a geological survey reference mark.

  8. 40 CFR 63.1329 - Process contact cooling towers provisions.

    Science.gov (United States)

    2010-07-01

    ...associated with a vacuum system to a process contact cooling tower. (2...that contact condenser effluent associated with vacuum systems is not sent to process contact cooling towers. (c...the cooling tower water shall be...

  9. Cooling tower symposium 1977

    International Nuclear Information System (INIS)

    Natural draft cooling towers are structures remarkable in many ways. They are extremely large shell structures, mainly affected by the wind load. It is above all the aerodynamic effects that have to be taken into account in cooling tower design. Their construction also differs in many ways from the construction of other buildings or structures and, finally, they are an unused-to sight in the landscape. The topics dealt with in this issue correspond to the lectures presented to the KIB symposium of 1977, giving a survey of the state-of-the-art at that time of cooling tower design and construction. (orig./HP)

  10. Genome Sequence of Legionella massiliensis, Isolated from a Cooling Tower Water Sample

    OpenAIRE

    Pagnier, Isabelle; Croce, Olivier; Robert, Catherine; Raoult, Didier; La Scola, Bernard

    2014-01-01

    We present the draft genome sequence of Legionella massiliensis strain LegAT, recovered from a cooling tower water sample, using an amoebal coculture procedure. The strain described here is composed of 4,387,007 bp, with a G+C content of 41.19%, and its genome has 3,767 protein-coding genes and 60 predicted RNA genes.

  11. Numerical study of coupled transfer of heat and mass between air and water inside a geothermal water cooling tower

    Science.gov (United States)

    Bassem, Mohamed Mehdi; Bourouni, Karim; Thameur Chaibi, Mohamed

    2006-11-01

    In the south of Tunisia, geothermal water is used to irrigate cultures. Since its temperature is very high (70 C), geothermal water is cooled by cooling towers. These towers are sized empirically and present many operating problems such as excessive energy consumption, big loss of vapour and low cooling efficiency. The aim of our work is modelling the coupled heat and mass transfer between air and water inside the cooling tower. The most important results obtained are that the evaporative potential is dominating the convective one in the cooling process. That's why the cooling is more efficient in summer than in hibernal period when humidity of ambient air reaches high values. In other hand, the negative convective phenomenon is illustrated. In fact, at the bottom of the tower, water temperature reaches the air one; the two fluids begin to cooling simultaneously. Air is cooled by convection and water by evaporation. We demonstrate also that there is no point in putting fans in working during cold weather. We studied also the effect of the variation of heat transfer coefficient on the efficiency of cooling.

  12. Determination of fan flow and water rate adjustment for off-design cooling tower tests

    International Nuclear Information System (INIS)

    The determination of the performance of a mechanical draft cooling tower requires that the air mass flow through the tower be known. Since this flow is not measured, it has been customary to use the manufacturer's design air flow and adjust it by the one-third power of the ratio of the design to test fan horsepower. The most nearly correct approximation of air flow through a tower can be obtained by incrementally moving through the tower from air inlet to outlet while calculating mass flows, energy balances, and pressure drops for each increment and then utilizing fan curves to determine volumetric and mass flows. This procedure would account for changes in air humidity and density through the tower, evaporation of water, effect of water rate on air pressure drop, and changes in fan characteristics. These type calculations may be within the capabilities of all in the near future, but for the interim, it is recommended that a more elementary approach be used which can be handled with a good calculator and without any proprietary data. This approach depends on certain assumptions which are acceptable if the tower test is conducted within CTI code requirements. The fan must be considered a constant suction volume blower for a given blade pitch. The total pressure at the fan, a function of volumetric flow and wet air density, must be assumed to be unaffected by other considerations, and the fan horsepower must be assumed to change only as volumetric flow and wet air density changes. Given these assumptions, along with design information normally provided with a tower, the determination of air flow through a tower in a test can be made from CTI test data. The air flow, and consequently the water rate adjustment and corrected water to air ratio, are derived and found to be direct functions of horsepower and density and an inverse function of wet air humidities

  13. INVESTIGATION OF THE PERFORMANCE OF AN ATMOSPHERIC COOLING TOWER USING FRESH AND SALTED WATER

    Directory of Open Access Journals (Sweden)

    A Haddad

    2012-01-01

    Full Text Available Cooling towers are extensively used to evacuate large quantities of heat at modest temperatures through a change of phase of the flowing cooling fluid. Based on this classical principle, the present study investigates the influence of salty water on the heat exchange produced. For that purpose, experiments are carried out using fresh and salty water. Furthermore, a comparison with the results produced through an approach involving the solution of energy equation involving the flow of air on an evaporating film of fluid. The detailed results show a preponderance of fresh water over the salty.

  14. A STUDY ON LEGIONELLA PNEUMOPHILA, WATER CHEMISTRY, AND ATMOSPHERIC CONDITIONS IN COOLING TOWERS AT THE SAVANNAH RIVER SITE

    Energy Technology Data Exchange (ETDEWEB)

    Smith, C.; Brigmon, R.

    2009-10-20

    Legionnaires disease is a pneumonia caused by the inhalation of the bacterium Legionella pneumophila. The majority of illnesses have been associated with cooling towers since these devices can harbor and disseminate the bacterium in the aerosolized mist generated by these systems. Historically, Savannah River Site (SRS) cooling towers have had occurrences of elevated levels of Legionella in all seasons of the year and in patterns that are difficult to predict. Since elevated Legionella in cooling tower water are a potential health concern a question has been raised as to the best control methodology. In this work we analyze available chemical, biological, and atmospheric data to determine the best method or key parameter for control. The SRS 4Q Industrial Hygiene Manual, 4Q-1203, 1 - G Cooling Tower Operation and the SRNL Legionella Sampling Program, states that 'Participation in the SRNL Legionella Sampling Program is MANDATORY for all operating cooling towers'. The resulting reports include L. pneumophila concentration information in cells/L. L. pneumophila concentrations >10{sup 7} cells/L are considered elevated and unsafe so action must be taken to reduce these densities. These remedial actions typically include increase biocide addition or 'shocking'. Sometimes additional actions are required if the problem persists including increase tower maintenance (e.g. cleaning). Evaluation of 14 SRS cooling towers, seven water quality parameters, and five Legionella serogroups over a three-plus year time frame demonstrated that cooling tower water Legionella densities varied widely though out this time period. In fact there was no one common consistent significant variable across all towers. The significant factors that did show up most frequently were related to suspended particulates, conductivity, pH, and dissolved oxygen, not chlorine or bromine as might be expected. Analyses of atmospheric data showed that there were more frequent significant elevated Legionella concentrations when the dew point temperature was high--a summertime occurrence. However, analysis of the three years of Legionella monitoring data of the 14 different SRS Cooling Towers demonstrated that elevated concentrations are observed at all temperatures and seasons. The objective of this study is to evaluate the ecology of L. pneumophila including serogroups and population densities, chemical, and atmospheric data, on cooling towers at SRS to determine whether relationships exist among water chemistry, and atmospheric conditions. The goal is to more fully understand the conditions which inhibit or encourage L. pneumophila growth and supply this data and associated recommendations to SRS Cooling Tower personnel for improved management of operation. Hopefully this information could then be used to help control L. pneumophila growth more effectively in SRS cooling tower water.

  15. Plumes from one and two cooling towers

    International Nuclear Information System (INIS)

    Use of mechanical- and natural-draft cooling towers is expanding in the United States in response to pressures for better resource allocation and preservation. Specifically, increasing public and regulatory concern over the effects of the intake and discharge of large volumes of cooling water has encouraged electric utilities to accept cooling towers as the primary method of removing condenser waste heat even though once-through cooling is considerably less expensive. Other factors encouraging the use of cooling towers include small water supply and consumption rates, reduction in land requirements (compared to cooling ponds or lakes), and operational flexibility. The growing demand for electric energy should also add to the increase of cooling tower use. The experimental program and its comparison to model prediction suggest that optimal siting of cooling towers, particularly multiple towers, is a task requiring knowledge of ambient wind history, plume dynamics, and tower operating conditions. Based on the tower wake effects and on the results for interaction of plumes from two cooling towers, site terrain may be a very significant factor in plume dynamics and interaction

  16. The future cooling tower; Fremtidens koeletaarn

    Energy Technology Data Exchange (ETDEWEB)

    Ibsen, C.H. (Vestas Aircoil A/S, Lem St. (Denmark)); Schneider, P. (Teknologisk Institut, AArhus (Denmark)); Haaning, N. (Ramboell A/S, Copenhagen (Denmark)); Lund, K. (Nyrup Plast A/S, Nyrup (Denmark)); Soerensen, Ole (MultiWing A/S, Vedbaek (Denmark)); Dalsgaard, T. (Silhorko A/S, Skanderborg (Denmark)); Pedersen, Michael (Skive Kommune, Skive (Denmark))

    2011-03-15

    This project has designed and built a pilot-scale cooling tower with an output of up to 100 kW for which good correlation has been ascertained between measured and calculated values for output and pressure loss. The new cooling tower will save approximately 15% of electricity consumption compared with the widespread dry coolers. The pilot tower uses rainwater so that both water consumption and electricity consumption are saved in softening plants. On the basis of this cooling tower, models have been made and these have been implemented in PackCalc II in order to calculate electricity and other operating savings. (Energy 11)

  17. Optimizing cooling tower performance refrigeration systems, chemical plants, and power plants all have a resource quietly awaiting exploitation - cold water

    International Nuclear Information System (INIS)

    The cooling towers are hidden bonanzas for energy conservation and dollar savings when properly engineered and maintained. In many cases, the limiting factor of production is the quality and quantity of cold water coming off the cooling tower. The savings accrued in energy conservation and additional product manufactured can be an important factor on the operator's company's profit and loss sheet (7). Energy management analysis is a very important consideration in today's escalating climate of costs of energy. It is advisable to consider a thorough engineering inspection and evaluation of the entire plant to leave no stone unturned iii the search to reduce energy consumption (8). The cooling tower plays the major role on waste heat removal and should be given a thorough engineering inspection and evaluation by a specialist in this field. This can be performed at nominal cost and a formal report submitted with recommendations, budget costs, and evaluation of the thermal, structural, and mechanical condition of the equipment. This feasibility study will assist in determining the extent of efficiency improvement available with costs and projected savings. It can be stated that practically all cooling towers can be upgraded to perform at higher levels of efficiency which can provide a rapid, cost-effective payback. However, while all cooling tower systems might not provide such a dramatic cost payback as these case histories, the return of a customer's investment in upgrading his cooling tower can be a surprising factor of operation and should not be neglected

  18. Hydraulic cooling tower driver

    International Nuclear Information System (INIS)

    One of the weaknesses of present day cooling tower drives are fan wrecks caused by shaft couplings breaking, gear box malfunctions due to inadequate lubrication, gear tooth wear, and inaccessibility for inspection and routine maintenance. The hydro-drive eliminates these items from the drive train and puts the same electric motor HP at ground level close coupled to a hydraulic pump, filters, and oil reservoir. Hydraulic lines bring oil pressure to the hydraulic motor, which is more than 75% less weight than comparable gear boxes and presents a smooth practically trouble free performance. In this three cell installation, the original 75 horsepower motors and 18' diameter fans were cooling a total of 14,000 GPM which were CTI tested at 74.7% of capability. The upgrading and retrofit consisted of installing at ground level 100 horsepower motors, 22' diameter fans, 14' high velocity recovery fan cylinders, V PVC splash bars, and high efficiency cellular drift eliminators. Testing indicates a 92% tower now circulating 21,000 GPM instead of the original 14,000

  19. Cooling towers and the microclimate

    International Nuclear Information System (INIS)

    Three different types of dry cooling towers and several types of cooling elements are studied and optimized on the basis of proposed design data. The most important possible effects on the microclimate are listed. A newly developed one-dimensional stationary computer model will help to calculate plumes of dry and wet cooling towers and their effects on the surrounding air down to the ground. Finally, current measurements are reported on. (UA/AK)

  20. Application of a semi-spectral cloud water parameterization to cooling tower plumes simulations

    Science.gov (United States)

    Bouzereau, Emmanuel; Musson Genon, Luc; Carissimo, Bertrand

    2008-10-01

    In order to simulate the plume produced by large natural draft cooling towers, a semi-spectral warm cloud parameterization has been implemented in an anelastic and non-hydrostatic 3D micro-scale meteorological code. The model results are compared to observations from a detailed field experiment carried out in 1980 at Bugey (location of an electrical nuclear power plant in the Rhône valley in East Central France) including airborne dynamical and microphysical measurements. Although we observe a slight overestimation of the liquid-water content, the results are satisfactory for all the 15 different cases simulated, which include different meteorological conditions ranging from low wind speed and convective conditions in clear sky to high wind and very cloudy. Such parameterization, which includes semi-spectral determination for droplet spectra, seems to be promising to describe plume interaction with atmosphere especially for aerosols and cloud droplets.

  1. Effects of wet cooling towers

    International Nuclear Information System (INIS)

    The paper, based on statistical data and model calculations with the SAUNA and WALKUERE codes, shows that the following effects of waste heat should be expected, although only in the direct neighbourhood (up to 10 km) of the cooling tower: 1) Reduced sunshine periods; 2) air humidity and temperature near the ground; 3) precipitations; 4) cloud formation; 5) inversion effects on the rise of cooling tower plumes, and 6) effects of the low-pressure area on the lee side of the cooling tower on plume dispersion. (HP)

  2. Environmental effects of cooling tower plumes

    International Nuclear Information System (INIS)

    Cooling tower plumes from natural draught wet cooling towers are consisting of 90% steam and 10% condensate. The water quantity going into the atmosphere via cooling towers e.g. at a power plant with an electrical output of 1,500 MW 3,000 t per hour on the average. The length of the plumes is depending on the individual weather situation and may be between 100 meters and a few kilometers. The vapour released by nuclear power plants is not nuclear activated. It contains a tiny amount of a radio-nuclear mixture and tritium (as tritiated water) of which the largest part is originated from the preliminary load of the cooling water. Cooling tower vapours have a small decreasing effect on the solar radiation. The effect of the solar radiation decrease on the vegetation, in the environment of power plants up to 200 m is very small, and can at further distances no longer be identified. The increase of rain will distribute itself in a district of approx. 1 km around the power plant and is probably less the 2% of the average annual rainfall. The cooling tower plumes will not cause violent weather conditions. The emission of dirt, salt and germs from the flow of cooling water is so small that there is no danger to public health. (orig.)

  3. Prevention of strong stench for stocked radioisotope sewerage using total water treatment agent for small-sized cooling towers

    International Nuclear Information System (INIS)

    In general, the sewerage at radioisotope laboratories has very strong stench. We treated the sewerage with a total water treatment agent (Tachileslegi, Nippon Nouyaku Co., Ltd. ) that is widely used for prevention of slime, scale, corrosion in cooling towers. As the result, the stench was decreased to about two thirds to that of control estimated by odor-test. (author)

  4. Technical Evaluation of Side Stream Filtration for Cooling Towers

    Energy Technology Data Exchange (ETDEWEB)

    None

    2012-10-01

    Cooling towers are an integral component of many refrigeration systems, providing comfort or process cooling across a broad range of applications. Cooling towers represent the point in a cooling system where heat is dissipated to the atmosphere through evaporation. Cooling towers are commonly used in industrial applications and in large commercial buildings to release waste heat extracted from a process or building system through evaporation of water.

  5. Technology to Facilitate the Use of Impaired Waters in Cooling Towers

    Energy Technology Data Exchange (ETDEWEB)

    Colborn, Robert

    2012-04-30

    The project goal was to develop an effective silica removal technology and couple that with existing electro-dialysis reversal (EDR) technology to achieve a cost effective treatment for impaired waters to allow for their use in the cooling towers of coal fired power plants. A quantitative target of the program was a 50% reduction in the fresh water withdrawal at a levelized cost of water of $3.90/Kgal. Over the course of the program, a new molybdenum-modified alumina was developed that significantly outperforms existing alumina materials in silica removal both kinetically and thermodynamically. The Langmuir capacity is 0.11g silica/g adsorbent. Moreover, a low cost recycle/regeneration process was discovered to allow for multiple recycles with minimal loss in activity. On the lab scale, five runs were carried out with no drop in performance between the second and fifth run in ability to absorb the silica from water. The Mo-modified alumina was successfully prepared on a multiple kilogram scale and a bench scale model column was used to remove 100 ppm of silica from 400 liters of simulated impaired water. Significant water savings would result from such a process and the regeneration process could be further optimized to reduce water requirements. Current barriers to implementation are the base cost of the adsorbent material and the fine powder form that would lead to back pressure on a large column. If mesoporous materials become more commonly used in other areas and the price drops from volume and process improvements, then our material would also lower in price because the amount of molybdenum needed is low and no additional processing is required. There may well be engineering solutions to the fine powder issue; in a simple concept experiment, we were able to pelletize our material with Boehmite, but lost performance due to a dramatic decrease in surface area.

  6. Keystone station cooling tower fill fouling

    International Nuclear Information System (INIS)

    This paper reports on Keystone Station which is a coal-fired nine-mouth electric generating station located 50 miles northeast of Pittsburgh in western Pennsylvania, with two 850 MW supercritical pressure generating units. Main condenser and service water cooling is provided by two natural draft hyperbolic cooling towers per unit. Each of the four cooling towers is 325 feet tall and 247 feet across at the basin. Operation of the station began in 1967. A consortium of mid-Atlantic utilities owns Keystone Station, and it is operated by the Pennsylvania Electric Company

  7. Counter-Flow Cooling Tower Test Cell

    OpenAIRE

    Dvo?ák Lukáš; Noži?ka Ji?í

    2014-01-01

    The article contains a design of a functional experimental model of a cross-flow mechanical draft cooling tower and the results and outcomes of measurements. This device is primarily used for measuring performance characteristics of cooling fills, but with a simple rebuild, it can be used for measuring other thermodynamic processes that take part in so-called wet cooling. The main advantages of the particular test cell lie in the accuracy, size, and the possibility of changing the water distr...

  8. Distribution of Sequence-Based Types of Legionella pneumophila Serogroup 1 Strains Isolated from Cooling Towers, Hot Springs, and Potable Water Systems in China

    OpenAIRE

    Qin, Tian; Zhou, Haijian; Ren, Hongyu; Guan, Hong; Li, Machao; Zhu, Bingqing; Shao, Zhujun

    2014-01-01

    Legionella pneumophila serogroup 1 causes Legionnaires' disease. Water systems contaminated with Legionella are the implicated sources of Legionnaires' disease. This study analyzed L. pneumophila serogroup 1 strains in China using sequence-based typing. Strains were isolated from cooling towers (n = 96), hot springs (n = 42), and potable water systems (n = 26). Isolates from cooling towers, hot springs, and potable water systems were divided into 25 sequence types (STs; index of discriminatio...

  9. AUTOMATED DEAD-END ULTRAFILTRATION FOR ENHANCED SURVEILLANCE OF LEGIONELLA 2 PNEUMOPHILA AND LEGIONELLA SPP. IN COOLING TOWER WATERS

    Energy Technology Data Exchange (ETDEWEB)

    Brigmon, R.; Leskinen, S.; Kearns, E.; Jones, W.; Miller, R.; Betivas, C.; Kingsley, M.; Lim, D.

    2011-10-10

    Detection of Legionella pneumophila in cooling towers and domestic hot water systems involves concentration by centrifugation or membrane filtration prior to inoculation onto growth media or analysis using techniques such as PCR or immunoassays. The Portable Multi-use Automated Concentration System (PMACS) was designed for concentrating microorganisms from large volumes of water in the field and was assessed for enhancing surveillance of L. pneumophila at the Savannah River Site, SC. PMACS samples (100 L; n = 28) were collected from six towers between August 2010 and April 2011 with grab samples (500 ml; n = 56) being collected before and after each PMACS sample. All samples were analyzed for the presence of L. pneumophila by direct fluorescence immunoassay (DFA) using FITC-labeled monoclonal antibodies targeting serogroups 1, 2, 4 and 6. QPCR was utilized for detection of Legionella spp. in the same samples. Counts of L. pneumophila from DFA and of Legionella spp. from qPCR were normalized to cells/L tower water. Concentrations were similar between grab and PMACS samples collected throughout the study by DFA analysis (P = 0.4461; repeated measures ANOVA). The same trend was observed with qPCR. However, PMACS concentration proved advantageous over membrane filtration by providing larger volume, more representative samples of the cooling tower environment, which led to reduced variability among sampling events and increasing the probability of detection of low level targets. These data highlight the utility of the PMACS for enhanced surveillance of L. pneumophila by providing improved sampling of the cooling tower environment.

  10. Cooling towers in the landscape

    International Nuclear Information System (INIS)

    The cooling tower as a large technical construction is one of the most original industrial buildings. It sticks out as an outlandish element in our building landscape, a giant which cannot be compared with the traditional forms of technical buildings. If it is constructed as a reinforced-concrete hyperboloid, its shape goes beyond all limits of building construction. Judgment of these highly individual constructions is only possible by applying a novel standard breaking completely with tradition. This new scale of height and dimension in industrial construction, and in particular the modern cooling tower, requires painstaking care and design and adaptation to the landscape around it. (orig.)

  11. Legionella detection and subgrouping in water air-conditioning cooling tower systems in Kuwait.

    Science.gov (United States)

    Al-Matawah, Qadreyah; Al-Zenki, Sameer; Al-Azmi, Ahmad; Al-Waalan, Tahani; Al-Salameen, Fadila; Hejji, Ahmad Ben

    2015-07-01

    The main aim of the study was to test for the presence of Legionnaires' disease-causing microorganisms in air-conditioned buildings in Kuwait using molecular technologies. For this purpose, 547 samples were collected from 38 cooling towers for the analysis of Legionella pneumophila. These samples included those from water (n?=?178), air (n?=?231), and swabs (n?=?138). Out of the 547 samples, 226 (41%) samples were presumptive positive for L. pneumophila, with L. pneumophila viable counts in the positive water samples ranging from 1 to 88 CFU/ml. Of the Legionella culture-positive samples, 204 isolates were examined by latex agglutination. These isolates were predominately identified as L. pneumophila serogroup (sg) 2-14. Using the Dresden panel of monoclonal antibodies, 74 representatives isolates were further serogrouped. Results showed that 51% of the isolates belonged to serogroup 7 followed by 1 (18%) and 3 (18%). Serogroups 4 (4%) and 10 (7%) were isolated at a lower frequency, and two isolates could not be assigned to a serogroup. These results indicate the wide prevalence of L. pneumophila serogroup 7 as the predominant serogroup at the selected sampling sites. Furthermore, the 74 L. pneumophila (sg1?=?13; sg3?=?13; sg4?=?3; sg7?=?38; sg10?=?5; sgX?=?2) isolates were genotyped using the seven gene protocol sequence-based typing (SBT) scheme developed by the European Working Group for Legionella Infections (EWGLI). The results show that Legionella isolates were discriminated into nine distinct sequence typing (ST) profiles, five of which were new to the SBT database of EWGLI. Additionally, all of the ST1 serogroup 1 isolates were of the OLDA/Oxford subgroup. These baseline data will form the basis for the development of a Legionella environmental surveillance program and used for future epidemiological investigations. PMID:25701245

  12. Biofilm formation comparison of the SANIPACKING® cooling tower fill material against standard polypropylene fill material in a recirculating model water system

    OpenAIRE

    TÜRETGEN, ?rfan; YÜRÜDÜ, Nazmiye Özlem ?ANLI; NORDEN, Imke

    2012-01-01

    Cooling towers are heat rejection systems that are used in some industrial applications, and they have the potential to develop infectious concentrations of Legionella pneumophila. SANIPACKING® cooling tower fill material and standard polypropylene fill material were compared in terms of biofilm formation potential and anti-Legionella activity within a 4-month period using a laboratory-scale recirculating water system. The recirculating water system was experimentally infected with a L. pneum...

  13. Modeling of Direct Contact Wet Cooling Tower in ETRR-2

    International Nuclear Information System (INIS)

    The Egyptian Testing and Research Reactor no.2 (ETRR-2) was commissioned at 1997 with maximum power 22 MW for research purposes; an induced draft wet cooling tower (counter flow type) was putted in operation in 2003 instead of the first one. Investigations are achieved to evaluate cooling tower performance to guarantee that the cooling tower capable to dissipate heat generated in reactor core. Merkel and Poppe analysis was applied to simulate this cooling tower packing. Merkel analysis was applied to predict water outlet temperature from cooling tower and also to show the effect of ambient conditions on this temperature. Poppe analysis was applied to predict Merkel number which evaluate cooling tower. The Runge-Kutta numerical method was applied to solve the differential equations in this model and an engineering equation solver (EES) is the language used to model the cooling tower. This research illustrates that the cooling tower achieves good performance in various sever ambient condition at maximum operating condition of reactor power. The results show that at severe summer condition of wet bulb temperature equals 24 degree c and tower inlet temperature equals 37 degree c, the outlet water temperature equals 30.4 degree c from cooling tower, while the Merkel number is be found 1.253

  14. Origin and prevention of infection with Legionella pneumophila through cooling towers and evaporative cooling towers

    International Nuclear Information System (INIS)

    Evaporative cooling towers and industrial ventilator cooling towers have repeatedly been described as the origin of Legionnaires' disease. This article describes the design and function of cooling towers and evaporative cooling towers, sums up knowledge on the colonization of such systems with Legionella pneumophila, and describes conditions permitting the transmission of Legionella. Furthermore, design, maintenance, cleaning and disinfection measures are indicated which are believed to reduce the risk of infection through industrial and evaporative cooling towers. (orig.)

  15. Treatment of auxiliary cooling tower water - influence on drainage canals and deposits

    International Nuclear Information System (INIS)

    The increasingly performed turning to re-cooled power plants, as a result of the waste heat problem, in connection with the water protection, required that the technical world has to do something about the problems of preliminary stresses of the surface waters, and the cooling water quality, necessary for the operation of power plants. The thickening of the cooling water in the circulation, connected with the wet re-cooling, as a result of evaporation, requires treatment of the water, taken for cooling purposes under several quality points of view. The water treatment procedures, practical according to the latest state of todays technology, show different influences on the returned cooling water, and on the residues occuring during the treatment (in accordance with the substances separated from the receiving canal). Therefore, depending on location the individual influence factors shall be determined and valuated during the selection of the treatment procedure. Make-up water quantity, raw water quality, quality of the returned water from the receiving canal (cleaning effect for the flow). Composition and storage ability of the residues from the water treatment. (orig.)

  16. Cooling tower analysis consideration of environmental factors

    International Nuclear Information System (INIS)

    This paper will survey the evolution of techniques used in the analysis of cooling towers over the past fifty years. It will also present two ways of analyzing the towers including the carryover on the cooling towers; performance. Cooling towers have been used in conventional fossil and nuclear power plants to remove waste heat from the condensers. This energy, in the form of low grade heat, must be transferred to the environment

  17. Three-dimensional numerical analysis of wet cooling tower

    International Nuclear Information System (INIS)

    A mathematical model for water evaporation and water droplet movement is established to describe the air-water interaction in natural draft wet cooling tower (NDWCT). The standard k - ? model is used to close the Reynolds average Navier-Stokes equations. The three-dimensional heat and mass transfer process in NDWCT is simulated to analyze the crosswind effect on wet cooling tower performance. It is found that the heat and mass transfer in fill zone is seriously affected by crosswind, while the wet cooling tower performance is improved when crosswind velocity is higher than 5 mcs-1. Conditions and locations for good cooling performance are pointed out

  18. Plant Vogtle cooling tower studies

    Energy Technology Data Exchange (ETDEWEB)

    O' Steen, L.

    2000-01-26

    Intensive ground-based field studies of plumes from two large, natural-draft cooling towers were conducted in support of the MTI modeling effort. Panchromatic imagery, IR imagery, meteorological data, internal tower temperatures and plant power data were collected during the field studies. These data were used to evaluate plume simulations, plume radioactive transfer calculations and plume volume estimation algorithms used for power estimation. Results from six field studies indicate that a 3-D atmospheric model at sufficient spatial resolution can effectively simulate a cooling tower plume if the plume is of sufficient size and the ambient meteorology is known and steady. Small plumes and gusty wind conditions degrade the agreement between the simulated and observed plumes. Thermal radiance calculations based on the simulated plumes produced maximum IR temperatures (near tower exit) which were in good agreement with measured IR temperatures for the larger plumes. For the smaller plumes, the calculated IR temperature was lower than the measured temperature by several degrees. Variations in maximum IR plume temperature with decreasing power (one reactor was undergoing a shutdown process), were clearly observed in the IR imagery and seen in the simulations. These temperature changes agreed with those calculated from an overall tower energy and momentum balance. Plume volume estimates based on camcorder images at three look angles were typically 20--30 percent larger than the plume volumes derived from the simulations, although one estimate was twice the simulated volume. Volume overestimation is expected and will have to be accounted for to some degree if plume volume is to be a useful diagnostic quantity in power estimation. Volume estimation with MTI imagery will require a large, stable plume and two looks in the visible bands (5m GSD) along with a solar shadow.

  19. The study on the evaporation cooling efficiency and effectiveness of cooling tower of film type

    Energy Technology Data Exchange (ETDEWEB)

    Li Yingjian, E-mail: szulyj@sohu.co [College of Chemistry and Chemical Engineering, Shenzhen University, Shenzhen 518060 (China); You Xinkui; Qiu Qi [College of Chemistry and Chemical Engineering, Shenzhen University, Shenzhen 518060 (China); Li Jiezhi [Ecole Centrale de Lyon 69130 (France)

    2011-01-15

    Based on heat and mass transport mechanism of film type cooling, which was combined with an on-site test on counter flow film type cooling tower, a mathematical model on the evaporation and cooling efficiency and effectiveness has been developed. Under typical climatic conditions, air conditioning load and the operating condition, the mass and heat balances have been calculated for the air and the cooling water including the volume of evaporative cooling water. Changing rule has been measured and calculated between coefficient of performance (COP) and chiller load. The influences of air and cooling water parameters on the evaporative cooling efficiency were analyzed in cooling tower restrained by latent heat evaporative cooling, and detailed derivation and computation revealed that both the evaporative cooling efficiency and effectiveness of cooling tower are the same characteristics parameters of the thermal performance of a cooling tower under identical assumptions.

  20. The study on the evaporation cooling efficiency and effectiveness of cooling tower of film type

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yingjian; You, Xinkui; Qiu, Qi [College of Chemistry and Chemical Engineering, Shenzhen University, Shenzhen 518060 (China); Li, Jiezhi [Ecole Centrale de Lyon 69130 (France)

    2011-01-15

    Based on heat and mass transport mechanism of film type cooling, which was combined with an on-site test on counter flow film type cooling tower, a mathematical model on the evaporation and cooling efficiency and effectiveness has been developed. Under typical climatic conditions, air conditioning load and the operating condition, the mass and heat balances have been calculated for the air and the cooling water including the volume of evaporative cooling water. Changing rule has been measured and calculated between coefficient of performance (COP) and chiller load. The influences of air and cooling water parameters on the evaporative cooling efficiency were analyzed in cooling tower restrained by latent heat evaporative cooling, and detailed derivation and computation revealed that both the evaporative cooling efficiency and effectiveness of cooling tower are the same characteristics parameters of the thermal performance of a cooling tower under identical assumptions. (author)

  1. Experimental data coupling atmospheric temperature inversions and cooling tower performances

    International Nuclear Information System (INIS)

    Two natural draft cooling towers were recently tested for which the authors obtained readings of the vertical profile of the temperature in the atmosphere. One is the cooling tower of the Unit 2 of the Belgian Nuclear Power Station of Tihange. The other is a cooling tower of the Gavin Power Station in Ohio (USA). These discussions are restricted to the effect of air density profiles on the thermal draft of these towers, and hence on the cooling tower performances (the cold water temperatures or the tower capability). The authors begin with theoretical reflections about the thermal draft, and continue with the report of the Tihange measurement results and the Gavin ones, before concluding with some recommendations

  2. Side Stream Filtration for Cooling Towers

    Energy Technology Data Exchange (ETDEWEB)

    None

    2012-10-20

    This technology evaluation assesses side stream filtration options for cooling towers, with an objective to assess key attributes that optimize energy and water savings along with providing information on specific technology and implementation options. This information can be used to assist Federal sites to determine which options may be most appropriate for their applications. This evaluation provides an overview of the characterization of side stream filtration technology, describes typical applications, and details specific types of filtration technology.

  3. Wet or wet/dry cooling tower

    International Nuclear Information System (INIS)

    A wet or wet/dry cooling tower is described having heat exchanger elements to provide heat exchange between water and cooling air and having an arrangement for transferring the cooled water to a return to the water distribution, the same having below the heat exchanger elements a number of adjacent inclined run-off surfaces, water-guiding plates into which the bottom longitudinal edges of the run-off surfaces merge, the plates having vertical areas and having channels which are disposed one above another and which extend transversely of the substantially vertical cooling-air flow, and water-collecting troughs which are disposed perpendicularly to the water-guiding plates at the bottom end of the lateral vertical edges of such plates, the run-off surfaces covering the distance between two adjacent water-guiding plates, the channels extending at an inclination to the horizontal and terminating in lateral vertical edges of such plates, characterised in that the run-off surfaces are connected by way of edged or rounded transition zones to the surface zones of the water-guiding plates and the channels are embodied by guide-groove structures which are stamped out of the surface zones at least on one side and which supply at least from the transition zones the cooling water from the run-off surfaces to the water-collecting troughs with the use of the surface tension of such water. 10 figs

  4. Improving the efficiency of natural draft cooling towers

    International Nuclear Information System (INIS)

    This study shows how the efficiency of a natural draft cooling tower can be improved by optimising the heat transfer along the cooling tower (CT) packing using a suitable water distribution across the plane area of the cooling tower. On the basis of cooling air measurements, it is possible to distribute the water in such a way that it approaches the optimal local water/air mass flow ratio and ensures the homogeneity of the heat transfer and a reduction of entropy generation, thus minimising the amount of exergy lost. The velocity and temperature fields of the air flow were measured with the aid of a remote control mobile robot unit that was developed to enable measurements at an arbitrary point above the spray zone over the entire plane area of the cooling tower. The topological structures of the moist air velocity profiles and the temperature profiles above the spray zone were used as input data for calculation of the local entropy generation in the tower. On the basis of the measured boundary conditions, a numerical analysis of the influence of the water distribution across the cooling tower's plane area on entropy generation and exergy destruction in the cooling tower was conducted

  5. Method for dimensioning crossflow cooling towers

    International Nuclear Information System (INIS)

    EDF has started a research programme relating to the operation of crossflow cooling towers. Tests have been conducted at the Nantes-Chevire bench as part of this programme: different fill configurations have been tested, varying the height and depth of the splash bars and the type of distribution nozzles. Measurements have also been taken in large cooling towers coupled with 900 MW(e) nuclear units. Test bench and on-site measurements consisted of vertical temperature and air velocity profiles at the inlet and outlet of the fill, as well as horizontal flow and water temperature profiles at the base of the fill. These readings have revealed horizontal transfer phenomena of the water flow and vertical transfer of the air flow, which are not portrayed by small test benches. These phenomena have been taken into account in a simplified two dimensional computation model of a crossflow fill, integrated to the TEFERI model. The results secured by computation using the exchange laws measured using the Nantes test bench are in good agreement with on-site measurements. This method has been applied to the prediction of efficiency of large cooling towers coupled with 1300 MW units and to the study of possible improvements to their operation

  6. Cooling towers of nuclear power plants

    International Nuclear Information System (INIS)

    The specifications are given of cooling towers of foreign nuclear power plants and a comparison is made with specifications of cooling towers with natural draught in Czechoslovak nuclear power plants. Shortcomings are pointed out in the design of cooling towers of Czechoslovak nuclear power plants which have been derived from conventional power plant design. The main differences are in the adjustment of the towers for winter operation and in the designed spray intensity. The comparison of selected parameters is expressed graphically. (J.B.)

  7. Optimization of cooling tower performance analysis using Taguchi method

    OpenAIRE

    Ramkumar Ramakrishnan; Ragupathy Arumugam

    2013-01-01

    This study discuss the application of Taguchi method in assessing maximum cooling tower effectiveness for the counter flow cooling tower using expanded wire mesh packing. The experiments were planned based on Taguchi’s L27 orthogonal array .The trail was performed under different inlet conditions of flow rate of water, air and water temperature. Signal-to-noise ratio (S/N) analysis, analysis of variance (ANOVA) and regression were carried out in order to determine the effects of process...

  8. Observed cooling tower plume characteristics

    International Nuclear Information System (INIS)

    In-plume measurements with an instrumented Cessna 411 aircraft were made at the Rancho Seco Nuclear Generating Station (913 MWe) near Sacramento, California; the Trojan nuclear plant (1130 MWe) on the Columbia River 50 mi. north of Portland, Oregon; and the coal-fired Centralia Steam Plant (1400 MWe) 50 mi. north of the Trojan plant. Additional surface-based operations conducted at Rancho Seco included pibal tracking to determine the wind velocity profile, time-exposure photographs of the plume for external plume definition and measurements of sulfate deposition due to the drift of entrained circulating water. Heat rejection at Rancho Seco is from two 425 ft. natural-draft towers whose exit diameters are 195 ft; at Trojan, from a single 500 ft. natural-draft tower with exit diameter of 250 ft; and at Centralia, from four mechanical-draft towers. Results of the analyses to date are summarized for three days' operation at Rancho Seco (February 17, 18, and 20 in 1975) and one day (May 13, 1976) at Trojan and Centralia. During the course of these flights, measurements of temperature, humidity, turbulence, Aitken nuclei, and cloud droplet spectra were taken

  9. Possible cooling tower designs and their economy

    International Nuclear Information System (INIS)

    The supporting shells of natural-draught cooling towers make very high demands on calculation and construction. Of the possible constructions, reinforced-concrete cooling towers constructed with the aid of climbing forms are the only ones which appear to be functional and economical. THe choice of the meridian curve of the cooling tower shell, which may be a hyperboloid of revolution or, in a more recent construction, of bell shape, is of great importance. In very large cooling towers, bracing rings cannot be dispensed with, as they improve the buckling and vibrational behaviour of the shell. This type of construction is also more economical than cooling tower shell with continuously varying shell thickness. (orig.)

  10. Comparison of plate counts, Petrifilm, dipslides, and adenosine triphosphate bioluminescence for monitoring bacteria in cooling-tower waters.

    Science.gov (United States)

    Mueller, Sherry A; Anderson, James E; Kim, Byung R; Ball, James C

    2009-04-01

    Effective bacterial control in cooling-tower systems requires accurate and timely methods to count bacteria. Plate-count methods are difficult to implement on-site, because they are time- and labor-intensive and require sterile techniques. Several field-applicable methods (dipslides, Petrifilm, and adenosine triphosphate [ATP] bioluminescence) were compared with the plate count for two sample matrices--phosphate-buffered saline solution containing a pure culture of Pseudomonas fluorescens and cooling-tower water containing an undefined mixed bacterial culture. For the pure culture, (1) counts determined on nutrient agar and plate-count agar (PCA) media and expressed as colony-forming units (CFU) per milliliter were equivalent to those on R2A medium (p = 1.0 and p = 1.0, respectively); (2) Petrifilm counts were not significantly different from R2A plate counts (p = 0.99); (3) the dipslide counts were up to 2 log units higher than R2A plate counts, but this discrepancy was not statistically significant (p = 0.06); and (4) a discernable correlation (r2 = 0.67) existed between ATP readings and plate counts. For cooling-tower water samples (n = 62), (1) bacterial counts using R2A medium were higher (but not significant; p = 0.63) than nutrient agar and significantly higher than tryptone-glucose yeast extract (TGE; p = 0.03) and PCA (p < 0.001); (2) Petrifilm counts were significantly lower than nutrient agar or R2A (p = 0.02 and p < 0.001, respectively), but not statistically different from TGE, PCA, and dipslides (p = 0.55, p = 0.69, and p = 0.91, respectively); (3) the dipslide method yielded bacteria counts 1 to 3 log units lower than nutrient agar and R2A (p < 0.001), but was not significantly different from Petrifilm (p = 0.91), PCA (p = 1.00) or TGE (p = 0.07); (4) the differences between dipslides and the other methods became greater with a 6-day incubation time; and (5) the correlation between ATP readings and plate counts varied from system to system, was poor (r2 values ranged from < 0.01 to 0.47), and the ATP method was not sufficiently sensitive to measure counts below approximately 10(4) CFU/mL. PMID:19445329

  11. Cooling towers - terms and definitions

    International Nuclear Information System (INIS)

    In the field of cooling tower construction and operation, the use of publications has shown that a systematic glossary has not yet been developed. Therefore a dictionary of the terms used in this field, together with their clear definitions, is urgently required. This work has been started by the V.I.K. (Association for the Industrial Power Economy) in Essen and completed by the VDI-Group 'Energy Engineering'. Because of the strong international links and the increasing overseas trade in this field also the corresponding terms in other languages, English, French and Spanish are included. As to make it possible to find the German terms and definitions when starting from a foreign language, alphabetical lists are included for the various languages giving the number of the corresponding German term. In such cases where the technical term used in the United States is not identical with the corresponding term used in the United Kingdom, both terms are included. (orig./HP)

  12. Corrosion control when using secondary treated municipal wastewater as alternative makeup water for cooling tower systems.

    Science.gov (United States)

    Hsieh, Ming-Kai; Li, Heng; Chien, Shih-Hsiang; Monnell, Jason D; Chowdhury, Indranil; Dzombak, David A; Vidic, Radisav D

    2010-12-01

    Secondary treated municipal wastewater is a promising alternative to fresh water as power plant cooling water system makeup water, especially in arid regions. Laboratory and field testing was conducted in this study to evaluate the corrosiveness of secondary treated municipal wastewater for various metals and metal alloys in cooling systems. Different corrosion control strategies were evaluated based on varied chemical treatment. Orthophosphate, which is abundant in secondary treated municipal wastewater, contributed to more than 80% precipitative removal of phosphorous-based corrosion inhibitors. Tolyltriazole worked effectively to reduce corrosion of copper (greater than 95% inhibition effectiveness). The corrosion rate of mild steel in the presence of free chlorine 1 mg/L (as Cl2) was approximately 50% higher than in the presence of monochloramine 1 mg/L (as Cl2), indicating that monochloramine is a less corrosive biocide than free chlorine. The scaling layers observed on the metal alloys contributed to corrosion inhibition, which could be seen by comparing the mild steel 21-day average corrosion rate with the last 5-day average corrosion rate, the latter being approximately 50% lower than the former. PMID:21214028

  13. Performance characteristics of counter flow wet cooling towers

    International Nuclear Information System (INIS)

    Cooling towers are one of the biggest heat and mass transfer devices that are in widespread use. In this paper, we use a detailed model of counter flow wet cooling towers in investigating the performance characteristics. The validity of the model is checked by experimental data reported in the literature. The thermal performance of the cooling towers is clearly explained in terms of varying air and water temperatures, as well as the driving potential for convection and evaporation heat transfer, along the height of the tower. The relative contribution of each mode of heat transfer rate to the total heat transfer rate in the cooling tower is established. It is demonstrated with an example problem that the predominant mode of heat transfer is evaporation. For example, evaporation contributes about 62.5% of the total rate of heat transfer at the bottom of the tower and almost 90% at the top of the tower. The variation of air and water temperatures along the height of the tower (process line) is explained on psychometric charts

  14. Effects of cooling towers. Auswirkungen von Kuehltuermen

    Energy Technology Data Exchange (ETDEWEB)

    Schikarski, W.

    1983-01-01

    A description is given of function, operational performance, emissions and effects, the emphasis being on showing the present state of knowledge on the diffusion and effects of plumes from cooling towers. Meteorological and chemical as well as microbiological aspects are dealt with. The state of knowledge of the superposition of several cooling tower plumes in a single location, noise pollution as well as aesthetic aspects are discussed. The commission is still arguing that meteorological location expertises are no more necessary for such cooling towers where the effects are concerned.

  15. On thermal performance of seawater cooling towers

    OpenAIRE

    Sharqawy, Mostafa H.; Lienhard, John H.; Zubair, Syed M.

    2010-01-01

    Seawater cooling towers have been used since the 1970s in power generation and other industries, so as to reduce the consumption of freshwater. The salts in seawater are known to create a number of operational problems, including salt deposition, packing blockage, corrosion, and certain environmental impacts from salt drift and blowdown return. In addition, the salinity of seawater affects the thermophysical properties that govern the thermal performance of cooling towers, including vapor pre...

  16. Enhancing performance of wet cooling towers

    International Nuclear Information System (INIS)

    The effect of windbreak walls on the thermal performance of natural draft wet cooling towers (NDWCT) under crosswind has been investigated numerically. The three dimensional CFD model has utilised the standard k-? turbulence model as the turbulence closure to quantify the effects of the locations and porosities of the wall on the NDWCT thermal performance. Moreover, the improvement in the NDWCT thermal performance due to windbreak walls has been examined at different crosswind directions. Results from the current investigation have demonstrated that installing solid impermeable walls in the rain zone results in degrading the performance of the NDWCT. However, installing solid walls at the inlet of the NDWCT has enhanced the NDWCT performance at all of the investigated crosswind velocities. Similarly, installing walls with low porosity has shown improvement in the performance of the NDWCT. A reduction of 0.5-1 K in the temperature of the cooling water coming from the tower to the condenser has been achieved at all of the investigated crosswind velocities by installing porous walls both inside and outside the rain zone

  17. Reducing the risk of Legionnaires' disease associated with cooling towers

    Energy Technology Data Exchange (ETDEWEB)

    Freije, M.R. [HC Information Resources Inc., Carlsbad, CA (United States)

    2008-08-15

    To reduce the health and legal risks associated with Legionnaires' disease, facility managers should take steps to minimize Legionella bacteria in plumbing systems, open industrial equipment, water features, cooling towers, and other aerosolizing water systems. The risk of Legionnaires' disease associated with cooling towers can be reduced by controlling Legionella bacteria in cooling water and preventing transmission of the bacteria from towers to people. This paper presents nine reasonable ways to accomplish these goals. (orig.)

  18. Design of SMART waste heat removal dry cooling tower using solar energy

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Yong Jae; Jeong, Yong Hoon [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2014-10-15

    The 85% of cooling system are once-through cooling system and closed cycle wet cooling system. However, many countries are trying to reduce the power plant water requirement due to the water shortage and water pollution. Dry cooling system is investigated for water saving advantage. There are two dry cooling system which are direct and indirect cooling system. In direct type, turbine exhaust is directly cooled by air-cooled condenser. In indirect system, turbine steam is cooled by recirculating intermediate cooling water loop, then the loop is cooled by air-cooled heat exchanger in cooling tower. In this paper, the purpose is to remove SMART waste heat, 200MW by using newly designed tower. The possibility of enhancing cooling performance by solar energy is analyzed. The simple cooling tower and solar energy cooling tower are presented and two design should meet the purpose of removing SMART waste heat, 200MW. In first design, when tower diameter is 70m, the height of tower should be 360m high. In second design, the chimney height decrease from 360m to 180m as collector radius increase from 100m to 500m due to collector temperature enhancement by solar energy, To analyze solar cooling tower further, consideration of solar energy performance at night should be analyzed.

  19. Design of SMART waste heat removal dry cooling tower using solar energy

    International Nuclear Information System (INIS)

    The 85% of cooling system are once-through cooling system and closed cycle wet cooling system. However, many countries are trying to reduce the power plant water requirement due to the water shortage and water pollution. Dry cooling system is investigated for water saving advantage. There are two dry cooling system which are direct and indirect cooling system. In direct type, turbine exhaust is directly cooled by air-cooled condenser. In indirect system, turbine steam is cooled by recirculating intermediate cooling water loop, then the loop is cooled by air-cooled heat exchanger in cooling tower. In this paper, the purpose is to remove SMART waste heat, 200MW by using newly designed tower. The possibility of enhancing cooling performance by solar energy is analyzed. The simple cooling tower and solar energy cooling tower are presented and two design should meet the purpose of removing SMART waste heat, 200MW. In first design, when tower diameter is 70m, the height of tower should be 360m high. In second design, the chimney height decrease from 360m to 180m as collector radius increase from 100m to 500m due to collector temperature enhancement by solar energy, To analyze solar cooling tower further, consideration of solar energy performance at night should be analyzed

  20. Distribution of Monoclonal Antibody Subgroups and Sequence-Based Types among Legionella pneumophila Serogroup 1 Isolates Derived from Cooling Tower Water, Bathwater, and Soil in Japan

    OpenAIRE

    Amemura-Maekawa, Junko; Kikukawa, Kiyomi; Helbig, Jürgen H.; Kaneko, Satoko; Suzuki-Hashimoto, Atsuko; Furuhata, Katsunori; CHANG, BIN; Murai, Miyo; Ichinose, Masayuki; Ohnishi, Makoto; Kura, Fumiaki

    2012-01-01

    Legionella pneumophila serogroup (SG) 1 is the most frequent cause of legionellosis. This study analyzed environmental isolates of L. pneumophila SG 1 in Japan using monoclonal antibody (MAb) typing and sequence-based typing (SBT). Samples were analyzed from bathwater (BW; n = 50), cooling tower water (CT; n = 50), and soil (SO; n = 35). The distribution of MAb types varied by source, with the most prevalent types being Bellingham (42%), Oxford (72%), and OLDA (51%) in BW, CT, and SO, respect...

  1. Structure of natural draft cooling towers, 1

    International Nuclear Information System (INIS)

    Thousands of natural draft cooling towers have been utilized, in Europe and America, as cooling systems of power plants or as countermeasures against thermal polution. Recently in Japan, demands for cooling tower systems have been increasing remarkably with the construction of large power plants and the legislation of environmental regulations. In view of the severe natural conditions in Japan such as strong wind and seismic loadings, etc., the establishment of the optimum design and construction method is essential for the building of safe and economical towers. In order to establish a comprehensive plan of a power plant cooling system of the appropriate structural type, the authors have made researches and experiments on design conditions, static and dynamic analyses, and comparative studies of various structural types such as reinforced concrete thin-shell structures, steel framed structures and composite shell segment structures, based on the investigation results of towers in Europe and America. These results are presented in three reports, the 1st of which concerns cooling tower shells as are hereinafter described. (auth.)

  2. Noise from cooling towers of power parks

    International Nuclear Information System (INIS)

    A study is presented of the noise pollution problem for large power parks proposed for the future. Such parks might have an area of about 75 sq. miles, and a generating capacity up to 48000 MW. A comparative analysis has been done for natural and mechanical-draft wet towers as the major sources of acoustic power. Noise radiation from single isolated towers as well as from a dispersed array of towers has been considered for both types of cooling systems. Major noise attenuation effects considered are due to the atmospheric absorption and A-weighting. Conditions of 60F and 70 percent relative humidity in a still atmosphere have been assumed

  3. Corrosion control studies in a mini cooling tower

    International Nuclear Information System (INIS)

    Generally, raw water is used for cooling the condensers in packaged air conditioning (AC) units installed in separate buildings. These AC units and their cooling water systems are operated on as-and-when required basis. The cooling water remains untreated generally. The Fast Breeder Test Reactor (FBTR) at Kalpakkam, TamiInadu, India is a 40 MWt sodium cooled, (uranium and plutonium) mixed carbide fuelled nuclear test reactor. In FBTR, four freon-based packaged AC units having 40 TR capacities with cooling water system have been installed in Annexe Building. Palar river water serves as the make-up to the system. The heat extracted from condensers is rejected in natural draft cooling tower. Initially, algae fouling and increased corrosion attacks were observed in the system. Sodium hypo chlorite dosing reduced the algae fouling considerably. Corrosion monitoring program was initiated with installation of corrosion monitoring set up. Inhibitors and dispersants like hydroxy ethylidene diphosphonic acid, sodium hexa meta phosphate, sodium dodecyl sulphate, ortho phosphoric acid and poly acrylic acid were used. It has been observed that minimum corrosion rate of 5 mpy could be obtained with 20 ppm of Hydroxy Ethylidene Diphosphonic Acid (HEDP) and 20 ppm of poly acrylic acid as against 9 mpy for the untreated water. This paper describes the problems associated with irregular operation of cooling water systems in corrosion control and experience gained in control of bio fouling and corrosion in cooling water system installed in packaged AC units having natural draft cooling tower. (author)

  4. Universal Engineering Model for Cooling Towers

    Directory of Open Access Journals (Sweden)

    Mohd Arif

    2015-05-01

    Full Text Available This paper presents a universal engineering model, which can be used to formulates both counter-flow and cross-flow cooling towers. By using fundamental laws of mass and energy balance, the effectiveness of heat exchange is approximated by a second order polynomial equation. Gauss -Newton and Levenberg-Marquardt methods are then used to determine the coefficients from manufactures data. Compared with the existing models, the new model has two main advantages: (1 As the engineering model is derived from engineering perspective, it involves fewer input variables and has better description of the cooling tower operation; (2 There is no iterative computation required, this feature is very important for online optimization of cooling tower performance. Although the model is simple, the results are very accurate. Application examples are given to compare the proposed model with commonly used models.

  5. Hybrid cooling towers in economic comparison with wet and dry cooling towers

    International Nuclear Information System (INIS)

    The hybrid cooling tower for Unit 5 at the Neckarwerke Electricity Supply Company, a bituminuous coal-fired unit with an installed capacity of 465 MW, erected in Altbach/Deizisau under a contract with the Neckar Heating Power Station Company, has been in operation since the middle of 1985 with a waste heat capacity of 558 MW. In the meantime the cooling tower has not only met the requirements imposed on it but has also permitted vapour plume-free operation on days with low atmospheric temperature - which has occurred more often than forecasted. Another cooling tower of the same design is currently being erected for the second unit of the Neckar Community Nuclear Power Station Company (GKN) at Neckarwestheim, 1300 MW 'convoy' unit. Its waste heat capacity is about 4.5 times as great. Using this cooling tower as an example an economic comparison is made with the natural draught cooling tower and with the dry cooling tower. The comparison led to the result that the hybrid cooling tower can be offered as a solution in special cases for future new power station construction and for retrofit installations. (orig.)

  6. The water-saving and environmentally-minded utilization of waste heat as a substitute for cooling towers-Agrotherm

    International Nuclear Information System (INIS)

    Since 1976 the conditions for the utilization of waste heat from power plants in agriculture has been investigated in different test plants in the F.R. of Germany. The system 'Agrotherm' is to substitute traditional cooling towers by closed underground pipe networks. The various investigations showed an overall increase of yield and premature harvest on acreages which had been heated by such pipe networks. The reactions of the various agricultures differ very much, so that a careful choice of sorts is necessary. Possibly considerable infestations of diseases must be expected. The article gives a summary of the most important results gained from the test plants. (KH)

  7. The shape of natural draft cooling towers

    International Nuclear Information System (INIS)

    The shape of cooling towers is more often designed empirically. There, it is considered from a theoretical point of view. The analysis of dynamic of natural draft and of the air flow in a cooling tower shell is presented. It is shown, that although it is convergent, a tower works like a diffuser for pressure recovery. And it is turbulence that produces a transfer of kinetic energy and allows a good operation of the diffusor. The equations permit to define a shell profile which depends upon the operating conditions of the cooling tower. In the same way, a stability criteria for natural draft depending upon operating conditions is established. A heating model of one meter diameter has been built in a thermal similitude. The turbulence rate has been measured with a hot wire anemometer at the tower exit and visualizations have also been made. Natural draft stability has been studied by these means for four different shell shapes and a wide range of operating conditions. Experimental and theoretical results agree satisfactorily and experiments can be considered as a validation of theory

  8. Energy savings: SCAM a new type of cooling tower

    International Nuclear Information System (INIS)

    Counter current natural draft cooling towers equipped with the device for cold water recovery and the adapted hydraulic circuit studied by CEM- (Compagnie Electro-Mecanique) SCAM system lead to a decrease in pumping energy. For a 1300 MW nuclear power plant energy saved is around 6 MWe, at the cost of energy in France in 1982 saving is F 4 500 000 which compensate for higher investment. They will be used in Golfech power plant; with a high of 178.5 m they will by the highest cooling towers in the world

  9. Cooling tower windage: a new aspect to environmental assessment

    International Nuclear Information System (INIS)

    Results of the several investigations provided quantitative estimates of windage from Oak Ridge Gaseous Diffusion Plant cooling towers. Windage water deposited on the ground has the potential to reach nearby streams through runoff. Windage deposited on moisture depleted soils would not be significant. During winter months at Oak Ridge soils generally have a high moisture content such that windage deposition could be quickly transported as runoff. It is during this time that cooling towers are sometimes operated without fan-induced draft. Since windage water contains the same hexavalent chromium concentration (9 ppM) as the recirculating cooling water system, the runoff stream from the K-892J tower constitues a NPDES violation as an unpermitted discharge. As a long-term abatement strategy, concrete aprons were constructed along each side of new cooling towers at the Paducah, Kentucky Gaseous Diffusion Plant. The maximum distance of windage impact is wind dependent. If apron construction is envisioned as an abatement strategy at Oak Ridge, the maximum distance of impact can be inferred graphically from the several points where windage (fans off) and drift (fans on) loss curves intersect under the different meteorological conditions. Once the hexavalent chromium laden runoff stream reaches Poplar Creek, it is diluted well below the standards for drinking water and poses little potential for biological effects to aquatic systems

  10. Indiana State University Graduates to Advanced Plastic Cooling Towers

    Science.gov (United States)

    Sullivan, Ed

    2012-01-01

    Perhaps more than many other industries, today's universities and colleges are beset by dramatically rising costs on every front. One of the areas where overhead can be contained or reduced is in the operation of the chilled water systems that support air conditioning throughout college campuses, specifically the cooling towers. Like many…

  11. Cooling towers, the overlooked energy profits generating center

    International Nuclear Information System (INIS)

    What is the effect of 0.6C (1F) temperature rise across turbines, compressors, or evaporators? Enthalpy charts indicate for every 0.6C (1F) hotter water off the cooling tower will require an additional 2 1/2 % more energy cost. Therefore, running 2.2C (4F) warmer due to substandard cooling towers could result in a 10% penalty for overcoming high heads and temperatures. If it costs $1,250,000.00 a year to operate the system, $125,000.00 is the energy penalty for hotter water. This paper will investigate extra fuel costs involved in maintaining design electric production with cooling water 0.6C (1F) to 3C (5.5F) hotter than design.design

  12. Dynamic analysis of hyperbolic cooling towers

    International Nuclear Information System (INIS)

    The methodology of analysis and the design criteria of a cooling tower as related to the wind and earthquake loads are reviewed based on the current state of the art for the two types of load. Recent development of the dynamic analysis for wind and earthquake loadings is discussed. Since the meridional tension is highly sensitive to the wind and earthquake forces, it is worthwhile to analyze the tower using the rational approach. The wind and earthquake loadings should be defined with great care. (Author)

  13. A systemic approach for optimal cooling tower operation

    International Nuclear Information System (INIS)

    The thermal performance of a cooling tower and its cooling water system is critical for industrial plants, and small deviations from the design conditions may cause severe instability in the operation and economics of the process. External disturbances such as variation in the thermal demand of the process or oscillations in atmospheric conditions may be suppressed in multiple ways. Nevertheless, such alternatives are hardly ever implemented in the industrial operation due to the poor coordination between the utility and process sectors. The complexity of the operation increases because of the strong interaction among the process variables. In the present work, an integrated model for the minimization of the operating costs of a cooling water system is developed. The system is composed of a cooling tower as well as a network of heat exchangers. After the model is verified, several cases are studied with the objective of determining the optimal operation. It is observed that the most important operational resources to mitigate disturbances in the thermal demand of the process are, in this order: the increase in recycle water flow rate, the increase in air flow rate and finally the forced removal of a portion of the water flow rate that enters the cooling tower with the corresponding make-up flow rate.

  14. Electrocoagulation to Remove Silica from Cooling Towers Water / Electrocoagulación para remover sílice en agua de torres de enfriamiento

    Scientific Electronic Library Online (English)

    Iván Emmanuel, Villegas-Mendoza; Alejandra, Martín-Domínguez; Sara, Pérez-Castrejón; Silvia Lucila, Gelover-Santiago.

    2014-06-01

    Full Text Available El presente artículo muestra los resultados de un estudio que se llevó a cabo para evaluar el efecto de la calidad del agua en la remoción de sílice disuelto mediante un proceso de electrocoagulación utilizando electrodos de aluminio. El sílice se encuentra en el agua de repuesto (RW) y de purga de [...] las torres de enfriamiento (CTBW). Las pruebas se hicieron a escala semipiloto a flujo continuo en un tren de tratamiento consistente de electrocoagulación (EC), floculación, sedimentación y filtración en arena. Se estudiaron dos RW y CTBW, con características fisicoquímicas diferentes. Las variables de respuesta analizadas fueron las siguientes: eficiencia del aluminio para remover sílice (relación mgl-1 de Al3+ dosificado/mgl-1 de sílice removido), eficiencia de remoción de Al3+ dosificado, pérdida de carga hidráulica a través del reactor electroquímico y el voltaje. Se calculó el costo del tratamiento de los cuatro tipos de agua. La relación mgl-1 de Al3+ dosificado/mgl-1 de sílice removido osciló de 1.09 ± 0.06 a 1.33 ± 0.05 al tratar RW, mientras que para CTBW fue de 0.85 ± 0.1. Los costos de energía, sustancias químicas y consumo de electrodos para el tratamiento de RW osciló de US$ 0.52 a US$ 0.74 m-3, y el costo del tratamiento de CTBW fue de aproximadamente US$ 0.53 m-3. Abstract in english This paper presents the results of a study carried out about the effect of water quality on the removal of dissolved silica using an electrocoagulation process with aluminum electrodes. Silica is found in replacement water (RW), usually known as make up water, and in cooling tower blowdown water (CT [...] BW). Tests were conducted on a small pilot scale (~2 lmin-1) with a continuous flow device. The treatment train consisted of electrocoagulation (EC), flocculation, sedimentation and sand filtration. Two distinct RW and two CTBW with different physicochemical characteristics were studied. The response variables analyzed were: efficiency of aluminum to remove silica (ratio mgl-1 of dosed Al3+/mgl-1 SiO2 removed), removal efficiency of dosed Al3+, hydraulic head loss throughout the electrochemical reactor and voltage. The cost of the treatment for the four types of water is discussed. The ratio mgl-1 Al3+ dosed /mgl-1 silica removed ranged from 1.09 ± 0.06 to 1.33 ± 0.05 when treating RW and 0.85 ± 0.1 when treating CTBW. The consumption costs of energy, chemicals and electrodes for RW treatment ranged from US$ 0.52 to 0.74 m-3, and was approximately US$0.53 m-3 for CTBW.

  15. Effectiveness of bromicide against Legionella pneumophila in a cooling tower

    Energy Technology Data Exchange (ETDEWEB)

    Fliermans, C.B.; Harvey, R.S.

    1983-01-01

    Cooling towers are considered to be man-made amplifiers of Legionella. Thus the proper maintenance and choice of biocides is important. The only biocide that has thus far been shown to be effective in field tests is the judicious use of chlorination. Perturbation studies were conducted on an industrial cooling tower shown to contain Legionella, using 1-bromo-3-chloro-5,5-dimethylhydantoin (Bromicide, Great Lakes Chemical Corp.). At the manufacturer's recommended concentrations neither the density nor the activity of Legionella was affected. At concentrations greater than 2.0 ppM free residual, the Bromicide was not effective in reducing Legionella to source water concentrations, nor was it effective in reducing the INT activity of the bacterium in situ. The data indicate that at concentrations up to 2.0 ppM, Bromicide is not effective in these tower studies. 23 references, 3 tables.

  16. European dry cooling tower operating experience

    International Nuclear Information System (INIS)

    Interviews were held with representatives of major plants and equipment manufacturers to obtain current information on operating experience with dry cooling towers in Europe. The report documents the objectives, background, and organizational details of the study, and presents an itemized account of contacts made to obtain information. Plant selection was based on a merit index involving thermal capacity and length of service. A questionnaire was used to organize operational data, when available, into nine major categories of experience. Information was also solicited concerning the use of codes and standards to ensure the achievement of cooling tower performance. Several plant operators provided finned-tube samples for metallographic analysis. Additionally, information on both operating experience and developing technology was supplied by European technical societies and research establishments. Information obtained from these contacts provides an updated and representative sample of European experience with dry cooling towers, which supplements some of the detailed reviews already available in the literature. In addition, the study presents categorized operating experience with installations which have not been reviewed so extensively, but nevertheless, have significant operational histories when ranked by the merit index. The contacts and interviews reported in the survey occurred between late March and October 1975. The study was motivated by the expressed interest of U.S. utility industry representatives who expect European experience to provide a basis of confidence that dry cooling is a reliable technology, applicable when necessary, to U.S. operating requirements

  17. Laboratory simulations of interactive plumes from mechanical draft cooling towers

    International Nuclear Information System (INIS)

    In connection with studies being conducted under the Meteorological Effects of Thermal Energy Releases (METER) Program, Pacific Northwest Laboratory (PNL) has been simulating discharges from physical models of mechanical draft cooling towers to determine the impact of various conditions in cooling tower plume mixing and trajectory. Analysis of the data suggests that siting cooling towers should be based on ambient wind history, plume dynamics, and tower operating conditions, and possibly on site terrain

  18. Test results of the cooling tower with the capacity of 100000 m/sup 3//h

    Energy Technology Data Exchange (ETDEWEB)

    Sereda, A.P.; Gorbenko, V.I.; Borisyuk, V.D.

    1984-02-01

    Unique cooling towers with the capacity of 100000 m/sup 3//h have been used for the first time in power generation practice of the USSR as coolers for the Rovno NPP circulation water supply. During tests in the summer-autumn, period of 1981 the thermohydraulic characteristics of such a tower were determined. The tests have shown that the tower has a high cooling efficiency in a wide range of thermal and hydraulic loadings. Deviation of actual temperatures of cooled water in the tower from their value, found according to nomograms, has not exceeded +-1.0 deg C.

  19. Realistic approximation of hyperbolic cooling towers

    International Nuclear Information System (INIS)

    A critical assessment of our present knowledge on the load and stress on hyperbolic cooling towers showed that this knowledge is still very restricted when measured values and rather extensive theoretical calculations are compared. This lack of knowledge has to be compensated for by relatively high safety coefficients which in turn reduce efficiency. In order to overcome the disproportion between extensive calculations and inaccurate results, a very simple, semi-empirical approximation method to determine the shell cutting forces due to stationary wind pressure was developed from model measurements. With this method, the wind frictional forces, which have until now always been neglected in spite of their importance can be included in the calculation. The exceptionally high sensitivity of hyperbolic cooling towers to earthquakes is also taken into consideration. (orig./AK)

  20. String net construction for a cooling tower

    International Nuclear Information System (INIS)

    On the site of the VEW power station 'Westfalen' near Uentrop-Schmehausen, 40 km east of Dortmund, a string net cooling tower is being constructed for the 300 MW THTR nuclear power station now under construction. The building, which has a total height of 180 m, will have a top diameter of 92 m and a basis diameter of 141 m. Its air outlet opening will be at a height of 146 m. (orig./AK)

  1. Recent developments of cooling tower design

    OpenAIRE

    HARTE, Reinhard; WITTEK, Udo

    2009-01-01

    Natural draught cooling towers (NDCT) are the characterizing landmarks of power stations. They contribute both to an efficient energy output and to a careful balance with our environment. In the last decade the building of new power plants stagnated all over the world. Nowadays the German power suppliers have started an extensive renewal program, where old units will be replaced by new ones, which will be much cleaner and more efficient. Besides innovative boiler techniques the sustainable an...

  2. Toward to the control system of mechanical draft cooling tower of film type

    Energy Technology Data Exchange (ETDEWEB)

    Fisenko, S.P.; Petruchik, A.I. [National Academy of Sciences of Belarus, Minsk (Belarus). A V Luikov Heat and Mass Transfer Inst.

    2005-01-01

    For changing atmospheric conditions the mathematical model of a control system of a mechanical draft cooling tower has been developed. The model includes a heat and mass transfer processes between water films and turbulent damp air flow at quasi-state approximation. Various regimes of cooling tower performance are compared and the optimization method is proposed. (author)

  3. Measurements on cooling tower plumes. Pt. 3

    International Nuclear Information System (INIS)

    In this paper an extended field experiment is described in which cooling tower plumes were investigated by means of three-dimensional in situ measurements. The goal of this program was to obtain input data for numerical models of cooling tower plumes. Data for testing or developing assumptions for sub-grid parametrizations were of special interest. Utilizing modern systems for high-resolution aerology and small aircraft, four measuring campaigns were conducted: two campaigns (1974) at the cooling towers of the RWE power station at Neurath and also two (1975) at the single cooling tower of the RWE power station at Meppen. Because of the broad spectrum of weather situations, it can be assumed that the results are representative with regard to the interrelationship between the structure of cooling tower plumes and the large-scale meteorological situation. A large number of flights with a powered glider ASK 16 (more than 100 flight hours) crossing the plumes on orthogonal tracks was performed. All flights showed that the plume could be identified up to large downwind distances by discontinuous jumps of temperature and vapour pressure. Therefore a definite geometry of the plume could always be defined. In all cross sections a vertical circulation could be observed. At the plumes boundaries, which could be defined by the mentioned jumps of temperature and vapour pressure, a maximum of downward vertical motion was observed in most cases. Entrainment along the boundary of a cross section seems to be very small, except at the lower part of the plume. There, the mass entrainment is maximum and is responsible for plume rise as well as for enlargement of the cross section. The visible part of the plume (cloud) was only a small fraction of the whole plume. The discontinuities of temperature and vapour pressure show that the plume fills the space below the visible plume down to the ground. However, all effects decrease rapidly towards the ground. It turned out that high-resolution aerology is necessary in order to explain the structure and behaviour of such plumes. This is especially the case in investigations regarding the dynamic break-through of temperature inversions. Such cases were observed quite frequently under various meteorological conditions and are described in this paper. (orig.)

  4. Modeling of existing cooling towers in ASPEN PLUS using an equilibrium stage method

    International Nuclear Information System (INIS)

    Highlights: ? Simulation of cooling tower performance under different operating conditions. ? Cooling tower performance is simulated using ASPEN PLUS. ? Levenberg–Marquardt method used to adjust model parameters. ? Air and water outlet temperatures are in good accordance with experimental data. - Abstract: Simulation of cooling tower performance considering operating conditions away from design is typically based on the geometrical parameters provided by the cooling tower vendor, which are often unavailable or outdated. In this paper a different approach for cooling tower modeling based on equilibrium stages and Murphree efficiencies to describe heat and mass transfer is presented. This approach is validated with published data and with data collected from an industrial application. Cooling tower performance is simulated using ASPEN PLUS. Murphree stage efficiency values for the process simulator model were optimized by minimizing the squared difference between the experimental and calculated data using the Levenberg–Marquardt method. The minimization algorithm was implemented in Microsoft Excel with Visual Basic for Applications, integrated with the process simulator (ASPEN PLUS) using Aspen Simulation Workbook. The simulated cooling tower air and water outlet temperatures are in good accordance with experimental data when applying only the outlet water temperature to calibrate the model. The methodology is accurate for simulating cooling towers at different operational conditions.

  5. Analysis of the evaporative towers cooling system of a coal-fired power plant

    Directory of Open Access Journals (Sweden)

    Lakovi? Mirjana S.

    2012-01-01

    Full Text Available The paper presents a theoretical analysis of the cooling system of a 110 MW coal-fired power plant located in central Serbia, where eight evaporative towers cool down the plant. An updated research on the evaporative tower cooling system has been carried out to show the theoretical analysis of the tower heat and mass balance, taking into account the sensible and latent heat exchanged during the processes which occur inside these towers. Power plants which are using wet cooling towers for cooling condenser cooling water have higher design temperature of cooling water, thus the designed condensing pressure is higher compared to plants with a once-through cooling system. Daily and seasonal changes further deteriorate energy efficiency of these plants, so it can be concluded that these plants have up to 5% less efficiency compared to systems with once-through cooling. The whole analysis permitted to evaluate the optimal conditions, as far as the operation of the towers is concerned, and to suggest an improvement of the plant. Since plant energy efficiency improvement has become a quite common issue today, the evaluation of the cooling system operation was conducted under the hypothesis of an increase in the plant overall energy efficiency due to low cost improvement in cooling tower system.

  6. Study on Characteristics of Special Turbine in Hydrodynamic Cooling Tower

    OpenAIRE

    Li Yanpin; Zhang Lanjin; Chen Dexin

    2012-01-01

    Today a special type of hydraulic turbine is used to replace electromotor to drive the fan in hydrodynamic cooling tower. This is a brand new turbine application. At present, systematic researching about the special turbine has still not been seen. The energy consumption of the electromotor is saved entirely because the power source comes from the surplus energy of circulating water system. But the special turbine works in a series of pressure flow system, its flow characteristic, working cha...

  7. First annual report on weather modification effects of cooling towers

    International Nuclear Information System (INIS)

    Single cooling towers emit as much as 1000 MW of sensible and latent heat to the atmosphere. Planned energy centers or power parks may contain clusters of cooling towers which emit a total of 100,000 MW. Heat releases of this magnitude have the potential to significantly alter local weather. Cooling towers can also alter the local environment by the production of fog and clouds, and the deposition of drift salts. A basic one-dimensional mathematical model is presented for plume and cloud growth in the vicinity of cooling towers. Since the cooling tower emissions are usually constant with time, at least over time periods less than four or five hours, the steady-state assumption is good. Phenomena such as multiple plume merging and changes in the environmental air surrounding the plume are accounted for only by crude parameterization. Applications in analysis of the environmental effects of cooling towers at fossil-fuel and nuclear power plants are reported

  8. Experimental study on the thermal performance of mechanical cooling tower with rotational splash type packing

    International Nuclear Information System (INIS)

    Highlights: • Effect of rotational packing on a counter flow wet cooling tower is experimented. • By increasing packing rotational velocity, water cooling range is increased. • Packing rotation does not have significant effect on water evaporation rate. • Packing rotation improves tower characteristic and heat rejection from water. • Increasing air temperature does not have positive effect on thermal characteristic. - Abstract: This paper deals with an experimental investigation of thermal performance of a forced draft counter flow wet cooling tower filled with a rotational splash type packing. Tower’s parameters are compared when the packing has been rotated and when it does not rotate (like common existing towers). However, no references regarding the effect of the rotational packing on the cooling tower performance have been found in the reviewed bibliography. The packing has 0.85 m2 area and consists of six horizontal wooden slats fixed on a threaded metallic shaft. This investigation is carried out for three inlet air temperatures 27 °C, 34 °C and 41 °C while water temperature is kept constant at 45 °C. The ranges of packing velocities are between 0 to 17 RPM and also several ranges of water to air flow rate ratio are experimented: 0.4 < L/G < 2.8. The obtained results showed that thermal characteristics of the cooling tower are affected by packing’s rotation. The results show that rotational splash type packing with higher rotational velocity rejects more heat from water considerably

  9. Windtunnel measurements of windload on cooling towers in group configuration

    International Nuclear Information System (INIS)

    The wind load conditions of the cooling tower set-up projected for Stendal nuclear power plant were tested in a wind tunnel model, compared with a solitary cooling tower, the transient wind load in a cooling tower group will be higher as referred to the steady wind load component. There is no danger of resonance vibrations in the given physical and constructional boundary conditions. (orig.)

  10. Stiffened cooling tower shells of reinforced concrete

    International Nuclear Information System (INIS)

    Presenting a kinetic method to derive the linear buckling and vibration problem of unstiffened and stiffened hyperboloidal cooling tower shells of reinforced concrete a parametric study is carried out using finite elements. The following parameters are varied: the type of axisymmetric load, the main geometric dimensions, the curvature of the meridional function and the type of stiffening, that means number, dimension and arrangement of meridional ribs and stiffening rings. The numerical results are interpreted. The tendencies recognizable are formulated and summarized in forme of recommendations. (orig.)

  11. Measurements at cooling tower plumes. Pt. 1

    International Nuclear Information System (INIS)

    Referring to the present status of knowledge model conceptions, assumptions and approaches are summarized, which can lead to mathematical models for the simulation of dry or wet cooling tower plumes. By developing a one-dimensional plume model (FOG) the most important problems are considered in detail. It is shown that for the calibration of the necessary parameters as well as for the development of models full scale measurements are of decisive importance. After a discussion of different possibilities of measurement the organisation of a campaign of measurement is described. (orig.)

  12. Cooling towers and prevention of legionella; Koeltorens en legionellapreventie

    Energy Technology Data Exchange (ETDEWEB)

    Schalekamp, J.D. [Afdeling Medische Milieukunde, Gemeentelijke Gezondheidsdienst voor Rotterdam en omstreken, Rotterdam (Netherlands)

    2001-03-01

    Two years ago an epidemic of legionellosis occurred on a flower show in the north of The Netherlands. It resulted in the biggest outbreak of legionnaires' disease in the world with more than 200 cases of legionellosis and an estimate of 28 deceased persons. The incident made prevention of legionellosis a major health topic in The Netherlands. However, little attention is given to the prevention of legionella bacteria in wet cooling towers. In the Netherlands, sporadic reports can be found about the presence of legionella bacteria in cooling towers. Cooling towers have n ever been associated with cases of legionnaires' disease, as whirlpools, faucets and showers have. Experiences elsewhere, for example in Australia and Great-Britain, show that the use of cooling towers imposes a health risk for persons in the surrounding area, i.e. inside the building or in the open air. The experiences and guidelines from other countries can be used to define rules for legionella prevention in Dutch cooling towers because the circumstances in cooling towers are universal: temperature, aeration and nutrients make cooling towers an ideal incubator for micro-organisms. Drift spreads little droplets containing legionella bacteria. Criteria for design, proper maintenance and monitoring can reduce the health risk. In the article, suggestions are given for preventive measures. As the exploitation costs of cooling towers will rise, and because health risks will never be reduced to zero, it is expected that wet cooling towers will gradually disappear. 8 refs.

  13. Method and system for simulating heat and mass transfer in cooling towers

    Science.gov (United States)

    Bharathan, Desikan (Lakewood, CO); Hassani, A. Vahab (Golden, CO)

    1997-01-01

    The present invention is a system and method for simulating the performance of a cooling tower. More precisely, the simulator of the present invention predicts values related to the heat and mass transfer from a liquid (e.g., water) to a gas (e.g., air) when provided with input data related to a cooling tower design. In particular, the simulator accepts input data regarding: (a) cooling tower site environmental characteristics; (b) cooling tower operational characteristics; and (c) geometric characteristics of the packing used to increase the surface area within the cooling tower upon which the heat and mass transfer interactions occur. In providing such performance predictions, the simulator performs computations related to the physics of heat and mass transfer within the packing. Thus, instead of relying solely on trial and error wherein various packing geometries are tested during construction of the cooling tower, the packing geometries for a proposed cooling tower can be simulated for use in selecting a desired packing geometry for the cooling tower.

  14. Natural draft cooling tower with shell disconnected from the substructure

    International Nuclear Information System (INIS)

    The aim of this paper is the analysis of results of a research done by Electricite de France, concerning a new type of cooling tower. The traditional structure (i.e. a hyperbolic shell supported by X shaped or diagonal columns) is replaced by two independent structures: the shell, becoming a self-contained structure, the lower rim being stiffened by an annular beam; the substructure, resting on the soil. This new type of cooling tower has an improved thermal performance due to the increase of the area of air entrance. Bearing pads are provided between the lower ring beam of the shell and the substructure. Any differential settlement can be coped with by jacking. The water distribution structure can be laid out so as to benefit from advantages offered by the presence of the stiff ring and columns of the substructure

  15. Studies of cooling tower components on the Mistral test bench

    International Nuclear Information System (INIS)

    The conception of a humid air cooling tower with natural or forced draught, requires the knowledge of the thermal and aerodynamic exchange surfaces performances. Several points, among which the distribution nozzles and drift eliminators efficiencies, or the mechanical behavior of the components, should be considered. In order to be able to test this type of equipment and analyse its behavior, ELECTRICITE DE FRANCE set up in 1987 of a large dimensions test bench: MISTRAL. The investigations performed over the 3000 working hours of MISTRAL concern mainly the optimization of the counterflow and crossflow exchange surfaces proposed by the industrial cooling tower equipment suppliers. The quality of the experimental results is assured by the implementation of an extensive instrumentation on the air and water circuits, and by a severe control of the tests conditions

  16. Efficiency control in a commercial counter flow wet cooling tower

    International Nuclear Information System (INIS)

    This paper presents open and closed-loop analyses of a counter flow wet cooling tower. The closed-loop system analysis was based on a comparative evaluation of three control strategies. The first and second comprised a split-range control of the cooling water temperature and an index of thermal performance (efficiency), respectively, and the third strategy comprised a combination of override and split-range control in order to control two performance indexes (efficiency and effectiveness). In this case, a SISO (Single-Input Single-Output) loop for each controlled variable is considered. In each case the water loss through evaporation and the energy consumption in the cooling tower (pump and fans) were estimated in order to analyze its eco-efficiency. All the simulation tests were carried out considering the same regulatory problem and the results show a notable improvement in the tower's performance when compared to open-loop operation, thus attesting the potential benefits of the use of an efficient control strategy for such equipment.

  17. Measurements at cooling tower plumes. Part 3. Three-dimensional measurements at cooling tower plumes

    International Nuclear Information System (INIS)

    An extended field experiment is described in which cooling tower plumes were studied by means of three-dimensional in situ measurements. The goal was to obtain input data for numerical models of cooling tower plumes. Of special interest were data for testing or developing assumptions for sub-grid parametrizations. Utilizing modern systems for high-resolution aerology and small aircraft, four measuring campaigns were conducted: two campaigns (1974) at the cooling towers of the RWE power station Neurath and also two (1975) at the single cooling tower of the RWE power station Meppen. Because of the broad spectrum of weather situations it can be assumed that the results are representative with regard to the interrelationship between structure of cooling tower plume and large-scale meteorological situation. A large number of flights with a powered glider crossing the plumes on orthogonal tracks was performed. All flights showed that the plume could be identified up to large downwind distances by discontinuous jumps of temperature and vapor pressure. Therefore, a definite geometry of the plume could always be defined. In all cross sections a vertical circulation could be observed. At the boundary, which could be defined by the mentioned jumps of temperature and vapor pressure, a maximum of downward vertical motion could be observed in most cases. Entrainment along the boundary of a cross section seems to be very small, except at the lower part of the plume. There, the mass entrainment is maximum and is responsible for plume rise as well as for enlargement of the cross section. The visible part of the plume (cloud) was only a small fraction of the whole plume. High-resolution aerology is necessary in order to explain the structure and behavior of such plumes. This is especially the case in investigations regarding the dynamic break-through of temperature inversions. Such cases were observed frequently under various meteorological conditions and are described

  18. Investigation of emissions of harmful substances in the cooling tower of the final coke oven gas cooling cycle

    International Nuclear Information System (INIS)

    It is known that the cooling tower of the open coke oven gas cooling cycle is the main source of emissions to the atmosphere of hydrogen cyanide. Desorption of volatile harmful substances in cooling tower depends on a large number of processing parameters and the compositions of the circulating water. The authors conducted a study of desorption of volatile components and a model of adequate scale of the final gas cooling cycle on an experimental industrial unit with a gas output of about 500 m3/hr. The unit was built at the Cherepovets Integrated Iron and Steel Works. In includes a cooling tower made of tubes 100 mm in diameter with a total height of about 5,100 mm. The volume of the lower part is 2.12 m3. Preliminary experimental evaluation of operation of the cooling tower according to the material and heat balances showed that it models operation of an industrial cooling tower quite well. Emissions of harmful substances in the cooling tower were determined by analyzing the circulating water and air before and after the cooling tower. Averaged samples for specified times were collected and the process parameters were simultaneously recorded (flow rates and temperatures of water and air), as well as the relative humidity and air pressure. Analysis of possible errors and the actual agreement of the determinations of the content of substances in air and water showed that evaluation of desorption of volatile components according to water analyses is more reliable (this conclusion is especially valid for industrial cooling towers). Results are described

  19. The Damaging Effects of Earthquake Excitation on Concrete Cooling Towers

    International Nuclear Information System (INIS)

    Reinforced concrete cooling towers of hyperbolic shell configuration find widespread application in utilities engaged in the production of electric power. In design of critical civil infrastructure of this type, it is imperative to consider all the possible loading conditions that the cooling tower may experience, an important loading condition in many countries is that of the earthquake excitation, whose influence on the integrity and stability of cooling towers is profound. Previous researches have shown that the columns supporting a cooling tower are sensitive to earthquake forces, as they are heavily loaded elements that do not possess high ductility, and understanding the behavior of columns under earthquake excitation is vital in structural design because they provide the load path for the self weight of the tower shell. This paper presents the results of a finite element investigation of a representative 'dry' cooling tower, using realistic horizontal and vertical acceleration data obtained from the recent and widely-reported Tabas, Naghan and Bam earthquakes in Iran. The results of both linear and nonlinear analyses are reported in the paper, the locations of plastic hinges within the supporting columns are identified and the ramifications of the plastic hinges on the stability of the cooling tower are assessed. It is concluded that for the (typical) cooling tower configuration analyzed, the columns that are instrumental in providing a load path are influenced greatly by earthquake loading, and for the earthquake data used in this study the representative cooling tower would be rendered unstable and would collapse under the earthquake forces considered

  20. Thermal performances investigation of a wet cooling tower

    International Nuclear Information System (INIS)

    This paper presents an experimental investigation of the thermal performances of a forced draft counter flow wet cooling tower filled with an 'VGA' (Vertical Grid Apparatus) type packing. The packing is 0.42 m high and consists of four (04) galvanised sheets having a zigzag form, between which are disposed three (03) metallic vertical grids in parallel with a cross sectional test area of 0.0222 m2 (0.15 m x 0.148 m). This study investigates the effect of the air and water flow rates on the cooling water range as well as the tower characteristic, for different inlet water temperatures. Two operating regimes were observed during the air water contact, a pellicular regime (PR) and a bubble and dispersion regime (BDR). These two regimes can determine the best way to promote the heat transfer. The BDR regime seems to be more efficient than the pellicular regime, as it enables to cool larger water flow rates. The comparison between the obtained results and those found in the literature for other types of packing indicates that this type possesses very interesting thermal performances

  1. Hydroaerothermal investigations conducted in the USSR to justify the construction of large cooling towers

    International Nuclear Information System (INIS)

    The multi-purpose task of improving water cooling systems of thermal and nuclear power plants is aimed at the development of efficient designs of cooling towers and other types of industrial coolers which call for comprehensive scientific justification. Cooling towers of 60-70 thou m3/h capacity with a chimney height of 130 m and those of 80-100 thou m3/h capacity with a chimney height of 150 m were developed. For circulating water systems of large power plants the design of a counterflow chimney cooling tower of 180 thou m3/h capacity has been recently developed. At present the work is being conducted on developing a new three-cell cooling tower featuring high reliability, operational flexibility and cost-effectiveness of the design. This cooling tower, besides having higher operating reliability than the conventional one of circular shape, can ensure the commissioning, current repairs and overhauls of water cooling arrangements in a cell-wise sequence, i.e. without shutting down the power generating units. Laboratory and field investigations of the spray-type cooling towers having no packing (fill), studies on heat and mass exchanges processes, aerodynamics of droplet flows and new designs of sprayers made it possible to come to a conclusion that their cooling capacity can be substantially increased and brought up to the level of the cooling towers with film packings. The pilot cooling towers were designed according to the counterflow, crossflow and cross-counterflow schemes. The basic investigation method remains to be the experimental one. On the test rigs and aerodynamic models the heat and mass transfer and aerodynamic resistance coefficients are determined. These studies and subsequent calculations are based on the heat balance equation

  2. Improving performance and reducing costs of cooling towers

    International Nuclear Information System (INIS)

    Cooling towers represent a significant capital investment at a steam electric power station. In addition, deficiencies in thermal performance can result in major operating penalties of fuel cost, replacement energy, and capacity addition. This paper summarizes two recent EPRI research projects aimed at reducing thermal performance deficiencies and decreasing installed costs of evaporative cooling towers. First, EPRI Research Project 2113, Cooling Tower Performance Prediction and Improvement, is summarized. This project has resulted in published data sets on the measured thermal performance characteristics of a variety of cooling tower packings, computer codes to predict tower performance, and computer code validation through large-scale tower performance measurements. Principal results are contained in an EPRIGEMS software module, Cooling Tower Advisor. This PC- based software contains a tutorial plus codes to predict tower thermal performance, arranged in a user-friendly format. The second EPRI effort, Research Project 2819-10/11, Fabric Structures for Power Plant Applications, has resulted in designs and costs of large structures with shells constructed of recently-developed fabrics. Primary power plant applications for such structures are the shells of natural draft cooling towers and coal-pile covers. Fabric structures offer low initial cost, acceptable life, and seismic superiority, among other advantages. Detailed conceptual designs and installed cost data are reviewed. 8 refs., 9 figs., 3 tabs

  3. Emission of air-borne pollutants from cooling towers

    International Nuclear Information System (INIS)

    The operation of natural-draught wet cooling towers involves water released to the atmosphere as vapour and by windage loss. The emission of pollutants are no physical or ecological problem, all the more so as no highly active raw waters are used for operation. Meteorological effects may be neglected. The same applies to the emission of chemicals and microorganisms. The effects of large buildings on the landescape must be assessed from a political angle. The electrical power industries is still requested to efficiently recuperate waste heat even in unfavourable locations. (DG)

  4. Thermal performance upgrade of the Arkansas Nuclear One cooling tower: A ''root cause'' analysis approach

    International Nuclear Information System (INIS)

    The thermal performance efficiency of the natural draft cooling tower at Entergy Operations' 858 MWe Arkansas Nuclear One, Unit 2 was successfully upgraded to 101% of design performance capability in April 1994 as the end result of a unique root-cause analysis of the cooling tower's long-standing performance deficiencies. Through application of state-of-the-art diagnostic testing methods and computer modeling techniques, Entergy was able to identify and correct air/water maldistribution problems in the 447 foot tall counterflow cooling tower at minimal cost. Entergy estimates that the savings realized, as a result of the 1.2 F reduction in cooling tower outlet water temperature, will pay for the thermal upgrade project in approximately 14 months

  5. Discrete model-based operation of cooling tower based on statistical analysis

    International Nuclear Information System (INIS)

    Highlights: • We introduce an index to describe the cooling capability of a cooling tower. • The effect of ambient air on cooling capability is studied by statistics analysis. • Physical-meaningful and precise-enough model is built by actual operation data. • The application to a real cooling tower is promising for energy conservation. - Abstract: This study is aimed to utilize the operation data to build a physical-meaningful and precise-enough model to assist the operation of a cooling tower. To do so, this work introduces a dimensionless index, which can describe the cooling capability of a cooling tower in terms of effective power utilization. In the first phase of this study, principal component analysis, one of factor analysis methods, is used to investigate effects of ambient air temperature and relative humidity on the cooling capability of a cooling tower. Based on the proposed cooling capability index, the operation data are partitioned into different groups by the fuzzy c-mean clustering algorithm. The resulted groups are distinctly categorized by the conditions of ambient air temperature and relative humidity. In the second phase of the study, data within the same mode of a set of fans are partitioned by the fuzzy c-mean clustering algorithm. The resulted groups of data are then modeled by linear regression. The acquired multiple models are highly accurate in predicting the output temperature of cooling water from the cooling tower. The acquired models assist the operator to accurately select the proper fan mode when process conditions, e.g., cooling loading, or environment conditions, e.g., ambient air temperature, change. It results in electricity saving. This study is concluded by the presentation of a discrete model-based approach to determine the fan mode. The application to a real cooling tower in an iron and steel plant is promising in saving electricity consumed by the fan set

  6. Strategy for the Operation of Cooling Towers with variable Speed Fans

    CERN Document Server

    Iñigo-Golfín, J

    2001-01-01

    Within the SPS Cooling Water Project at CERN aimed at the reduction of water consumption, this primary open cooling loop will be closed and all the primary cooling circuit components will be upgraded to the new required duty and brought to the necessary safety and operability standards. In particular the tower fans will be fitted with variable frequency drives to replace the existing two speed motors. This paper presents a study to optimize the operation of SPS cooling towers taking into account outdoor conditions (wet and dry bulb temperatures) and the entirety of the primary circuit in which they will operate.

  7. Design of a water tower in steel

    OpenAIRE

    Nicolaou, Irini

    1994-01-01

    The main objective of this project is t? design a Water Tower in Steel for potable water. The Water Tower will be constructed to act as a water reservoir, in a water supply system. The size of the tank depends on the capacity of water to be stored. The cost of Water Tower depends mainly on its shape and on the type of structural material that is going to be used. In this project the Water Tower is made of Mild Steel, Grade 43. The choice of the shape was done, taking into account the di...

  8. Thermal performance of a fluidized bed cooling tower

    Energy Technology Data Exchange (ETDEWEB)

    Egbe, L.M.; Lewis, J.S.; Barham, P. [Middlesex University, London (United Kingdom). School of Engineering Systems; Kubie, J. [Napier University, Edinburgh (United Kingdom). School of Engineering

    1999-07-01

    Experiments have been performed to measure the thermal performance of a fluidized bed cooling tower of 290 mm diameter. Hollow plastic spheres of three different sizes, with diameters of 20, 25.4 and 37.5 mm and particle densities ranging from 69 to 326 kg/m{sup 3} were investigated as packing materials, and results for static bed heights of 100 mm and 300 mm are reported. Measurements were obtained at an approximately constant inlet hot water temperature of around 42{sup o}C and cover a range of water mass flux from 0.3 to 3.6 kg/s m{sup 2}. Liquid/gas ratios varied between 0.1 and 5.5. Results for thermal performance are presented showing the effects on the cooling tower characteristic, KaV/L, of the different packing elements and of varying water flow rate, air flow rate and the height of the hot water distributor above the bed. (author)

  9. Experimental investigation of the hydraulic characteristics of a counter flow wet cooling tower

    International Nuclear Information System (INIS)

    Thermal and nuclear electric power plants as well as several industrial processes invariably discharge considerable energy to their surrounding by heat transfer. Although water drawn from a nearby river or lake can be employed to carry away this energy, cooling towers offer an excellent alternative particularly in locations where sufficient cooling water cannot be easily obtained from natural sources or where concern for the environment imposes some limits on the temperature at which cooling water can be returned to the surrounding. This paper concerns an experimental investigation of the hydraulic characteristics of a counter flow wet cooling tower. The tower contains a 'VGA.' (Vertical Grid Apparatus) type packing which is 0.42 m high and consists of four (04) galvanised sheets having a zigzag form, between which are disposed three (03) metallic vertical grids in parallel with a cross sectional test area of 0.15 m x 0.148 m. The present investigation is focused mainly on the effect of the air and water flow rates on the hydraulic characteristics of the cooling tower, for different inlet water temperatures. The two hydrodynamic operating regimes which were observed during the air/water contact operation within the tower, namely the Pellicular Regime (PR) and the Bubble and Dispersion Regime (BDR) have enabled to distinguish two different states of pressure drop characteristics. The first regime is characterized by low pressure drop values, while in the second regime, the pressure drop values are relatively much higher than those observed in the first one. The dependence between the pressure drop characteristics and the combined heat and mass transport (air-water) through the packing inside the cooling tower is also highlighted. The obtained results indicate that this type of tower possesses relatively good hydraulic characteristics. This leads to the saving of energy. -- Highlights: ? Cooling towers are widely used to reject waste heat from thermal and nuclear electric power plants to the atmosphere. ? The hydraulic characteristics of a counter flow wet cooling tower have been studied experimentally. ? The effect of the air and water flow rates on the hydraulic characteristics of tower was investigated. ? Different inlet water temperatures: 35 oC, 43 oC and 50 oC, respectivelly, were used in the investigation. ? The results indicate that this type of tower possesses relatively good hydraulic characteristics.

  10. Numerical simulation of visible plumes of mechanical draft cooling towers

    International Nuclear Information System (INIS)

    The numerical model SMOKA for moist buoyant plumes is calibrated with measured data from single large natural draft cooling towers. This investigation checks the applicability of the model on groups of low mechanical draft cooling towers. The needed meteorological and technical data were measured during the homologation tests at the nuclear power plant Isar/Ohu in Southern Germany. The visible plumes were simulated for 16 test cases. The calculated plume lengths agree with the observations well, however in strong wind situations the calculated plume heights are too low. The results of these test cases supply a basis for the interpretation of further model calculations with low cooling tower groups. (orig.)

  11. State of development of centripetal ventilators for cooling towers

    International Nuclear Information System (INIS)

    In the nuclear power station at Biblis, the conventional central cooling tower ventilator has been replaced by a large number of smaller axial ventilators arranged on the outer shell of the cooling tower in the air intake region. Tests have been carried out with the aim of finding a practicable blade system for a centripetal cooling tower ventilator. The blower veel diameter of this model ventilator is about 1 m. Using the model laws, the knowledge gained here may be applied to large-scale systems with diameters of 100-150 m or more. (orig.)

  12. Fire behaviour of cooling tower packing; Brandverhalten von Kuehlturmeinbauten

    Energy Technology Data Exchange (ETDEWEB)

    Mattausch, Tim [DMT GmbH und Co. KG, Dortmund (Germany). Fachstelle fuer Brandschutz

    2013-10-01

    The rapid burning down of the cooling tower of the shutdown power plant in Schwandorf revealed the potential of a total loss of a cooling tower in case of fire. VGB ordered a research project in order to obtain more knowledge about the fire risk of cooling tower packing currently applied. Depending on kind and age of the plastics used, the results of these tests manifest a big variation of the fire behaviour. For the applications of plastics, it is essential to determine and to adhere to organisational fire protection measures. (orig.)

  13. CTP method - diagnostic method for control of cooling tower operation

    International Nuclear Information System (INIS)

    Optimal operation of cooling towers of thermal systems, such as fossil-fired power plants, nuclear power plants, heating plants, thermal systems in process and petro-chemical industry, significantly raises the efficiency of the entire systems. With the reconstruction of cooling towers and introduction of new technologies significant economic and ecologic profits could be expected. The increased system efficiency after cooling tower reconstruction is estimated from 2 to 5%, what is an enormous amount of energy and money saving considering the output power of such systems. Within the frame of the EU Copernicus Project 'OCTEBAMA', a modification of the described method was performed. (orig.)

  14. Numerical simulation of a cooling tower coupled with heat pump system associated with single house using TRNSYS

    International Nuclear Information System (INIS)

    Highlights: • We simulate a cooling tower coupled with heat pump system and a single zone using TRNSYS. • We examine the temperature of water inside the cooling tower and inside the single zone. • We study the temporal evolution of the all parameters for 4500 h operation in winter in Tunisia. - Abstract: The industrial cooling towers in Tunisia meet difficulties due to the poor coordination between the utility and process sectors. In this study, we will consider especially the vapor recovery of the wastewater from the industrial activity in south Tunisia. By using the heat pump for high capacity, the problem for vapor from wastewater may be resolved. The coupling for the cooling tower and the heat pump system is investigated by TRNSYS software. The system of cooling tower is also associated with a single zone which is related to heat exchangers. An optimization model for the operation of a cooling water system was developed that accounts for a cooling tower, and a network of pipelines and heat exchangers for heating a single house. This work is based on numerical studies; the cooling tower performance, the single house, the heat pump and the heat exchanger that are simulated using TRNSYS model. The circulation of cooling water system is assured by a counter flow. The evaluations of the cooling tower geometry and performances are based on an adaptive version of Merkel’s method witch integrated in TRNSYS. The results of optimization using TRNSYS are validated by several theoretical and experimental studies

  15. Dynamic behavior and identification of failure modes of cooling towers

    International Nuclear Information System (INIS)

    The major thrust of this paper is to provide an engineering assessment of two hyperboloidal 540-foot high reinforced concrete cooling towers at a nuclear power plant relative to the proposed construction of a new safety-related facility in the shadow of these cooling towers. A three-dimensional full 360-degree finite-element model that is capable of realistically representing the response of the two cooling towers subjected to the plant design-basis safe shutdown earthquake, 90 mph wind, and 300 mph tornado is used to create a data pool which supports the proposed construction of the new facility. Dynamic time history analyses are performed to represent the complex interplay of the dynamic characteristics of the cooling towers and the input wind-pressure excitation in terms of gust factors. This study resulted in the confirmation and enhancement of many of the important aspects in the design/analysis methodologies for cooling towers reported in literature. In summary, this study provides a high confidence that no significant damage will be caused to the two cooling towers when subjected to the plant design-basis safe shutdown earthquake and the 90 mph basic wind velocity. However, the two cooling towers are expected to collapse if subjected in a direct hit to a 300 mph tornado. The nonlinear finite element analyses including base uplift performed for this study and the literature research on past failures of cooling towers due to severe wind storms confirm that the mode of failure will not be the overturning cantilever tree-type and the towers will collapse inwardly with the exception of few isolated debris

  16. Experimental investigation of the performance characteristics of a counterflow wet cooling tower

    International Nuclear Information System (INIS)

    An experimental investigation of the performance characteristics of a counter flow wet cooling tower represented by the heat rejected by the tower and its thermal effectiveness is presented in this paper. The tower is filled with a 'VGA.' (Vertical Grid Apparatus) type packing which is 0.42 m high and contains four (04) galvanized sheets having a zigzag form, between which are disposed three (03) metallic vertical grids in parallel with a cross-sectional test area of 0.15 m - 0.148 m. The investigation is concerned mainly on the effect of the air, water flow rates and the inlet water temperatures on the thermal effectiveness of the cooling tower as well as the heat rejected by this tower from water to be cooled to the air stream discharged into the atmosphere. The two operating regimes which were observed during the air/water contact inside the tower, a Pellicular Regime (PR) and a Bubble and Dispersion Regime (BDR) appear to be important, as The BDR regime enables to cool larger amount of water flow rates, while the Pellicular regime results with higher thermal effectiveness. (authors)

  17. Numerical study on the cooling performance of dry cooling tower with vertical two-pass column radiators under crosswind

    International Nuclear Information System (INIS)

    To study the cooling performance of a natural draft dry cooling tower with vertical two-pass column radiators (NDDCTV) under crosswind, a three-dimensional (3D) numerical model was established for NDDCTV and validated by some published results. By the numerical model, the aerodynamic field around cooling columns was computed and analyzed at 4 m/s crosswind. It was found that the large inflow air deviation angle at delta entry induced large eddy near column ??1. With the air static pressure contours, the air mass flow rates through each column, delta and sector were analyzed and calculated. Based on the water temperature distribution at column exits, the exit water temperatures of each column, delta and sector were presented and analyzed. So the crosswind impact mechanism on each sector and the tower was clarified. With the increasing crosswind velocity, the cooling performance of tower deteriorates rapidly. But at high velocity crosswind, the tower performance varies gently. - Highlights: • A 3D numerical model was set up for NDDCTV with two-pass radiators around tower. • The aerodynamic field around cooling deltas was analyzed under crosswind impact. • An inflow air deviation angle was used to clarify the column cooling performance. • Cross wind effect on NDDCTV cooling performance was elaborated from columns

  18. Evaluation of IR technology applied to cooling tower performance

    Science.gov (United States)

    MacNamara, Neal A.; Zayicek, Paul A.

    1999-03-01

    Infrared thermography (IR) is widely used by electric utilities as an integral part of their predictive maintenance program. IR is utilized for inspection of a variety of plant mechanical and electrical components. Additionally, IR can be used to provide thermal performance information for other key plant systems, including assessment of cooling towers. Cooling tower performance directly affects availability and heat rate in fossil and nuclear power plants. Optimal tower performance contributes to efficient turbine operation and maximum power output. It is estimated that up to half of the cooling towers installed have failed to meet their design performance specifications. As a result, any additional degradation of tower performance resulting from fouling, valve degradation, unbalanced flow, or a poor maintenance practice has a direct effect on generation output. We have collected infrared thermography images of mechanical draft cooling towers, as part of Evaluation of IR Technology Applied to Cooling Tower Performance. IR images have been analyzed to provide information regarding general performance conditions and identification of operational deficiencies related to thermal performance. Similarly, IR can be implemented for monitoring of tower flow balance activities and for post-maintenance surveillance. To date, IR images have been used to identify areas of general flow imbalance, flooding or limited flow in individual cells, missing or broken tower fill material, fan performance and other problems related to maintenance or operational issues. Additionally, an attempt is being made to use quantitative thermal data, provided by the IR image analysis software, in conjunction with condenser input/output site ambient information, to evaluate and compare individual tower cell performance.

  19. Stimulatory effect of cooling tower biocides on amoebae.

    OpenAIRE

    Srikanth, S.; Berk, S G

    1993-01-01

    Two species of amoebae were isolated from the cooling tower of an air-conditioning system and examined for effects of exposure to four cooling tower biocides, a thiocarbamate compound, tributyltin neodecanoate mixed with quaternary ammonium compounds, another quaternary ammonium compound alone, and an isothiazolin derivative. The amoebae isolated were Acanthamoeba hatchetti and a Cochliopodium species. Two other amoeba cultures, an A. hatchetti culture and Cochliopodium bilimbosum, were obtai...

  20. Experimental study on the performance of mechanical cooling tower with two types of film packing

    Energy Technology Data Exchange (ETDEWEB)

    Gharagheizi, Farhad [Department of Chemical Engineering, Faculty of Engineering, University of Tehran, PO Box 11365-4563, Tehran (Iran, Islamic Republic of)]. E-mail: fghara@engmail.ut.ac.ir; Hayati, Reza [Department of Chemical Engineering, Faculty of Engineering, University of Tehran, PO Box 11365-4563, Tehran (Iran, Islamic Republic of); Fatemi, Shohreh [Department of Chemical Engineering, Faculty of Engineering, University of Tehran, PO Box 11365-4563, Tehran (Iran, Islamic Republic of)

    2007-01-15

    In this work, an experimental and a comparative study on terms of tower characteristics (KaV/L), water to air flow ratio (L/G) and efficiency for two film type packings are presented for a wide range of (L/G) ratio from 0.2 to 4. The packings used in this work are vertical corrugated packing (VCP) and horizontal corrugated packing (HCP). The obtained results showed that the performance of the cooling tower is affected by the type and arrangement of the packings. Also, the tower performance showed a decrease with an increase in the (L/G) ratio as is also observed in other types of cooling towers. The results showed the tower with vertical corrugated packing (VCP) has higher efficiency than the one with horizontal corrugated packing (HCP)

  1. Assessment of the effect of water source of health risk in a pilot project to promote the reuse of reclaimed water in cooling towers; Valoracion del efecto del origen del agua en el riesgo sanitario en una experiencia piloto para promover la reutilizacion de agua regenerada en torres de refrigeracion

    Energy Technology Data Exchange (ETDEWEB)

    Fittipaldi, M.; Codony, F.; Puigdengoles, J. M.; Molist; Morato, J.

    2009-07-01

    Wastewater regeneration and reuse of regenerated water permits to increase the amount of water and guarantees the availability required, in terms of both quantity and quality. In this context, a research project on regenerated water reuse for cooling towers has been carried out by the Universitat Politecnica de Catalunya (UPC), the Water Catalan Agency (ACA) and the Council of Chambers of Commerce. The research consisted of two steps. A first objective was to verify the effect of water source in the colonization of cooling towers by Legionella. In order to achieve those objectives, effluents from different wastewater treatment plant stages were used. The second objective was to evaluate in situ the disinfection process in order to decrease the sanitary risk from water reuse for cooling towers. For the entire duration of the project, both conventional culture methods and new molecular techniques with real times PCR were performed to detect Legionella from water samples. (Author) 17 refs.

  2. High Flux Isotopes Reactor (HFIR) Cooling Towers Demolition Waste Management

    Energy Technology Data Exchange (ETDEWEB)

    Pudelek, R. E.; Gilbert, W. C.

    2002-02-26

    This paper describes the results of a joint initiative between Oak Ridge National Laboratory, operated by UT-Battelle, and Bechtel Jacobs Company, LLC (BJC) to characterize, package, transport, treat, and dispose of demolition waste from the High Flux Isotope Reactor (HFIR), Cooling Tower. The demolition and removal of waste from the site was the first critical step in the planned HFIR beryllium reflector replacement outage scheduled. The outage was scheduled to last a maximum of six months. Demolition and removal of the waste was critical because a new tower was to be constructed over the old concrete water basin. A detailed sampling and analysis plan was developed to characterize the hazardous and radiological constituents of the components of the Cooling Tower. Analyses were performed for Resource Conservation and Recovery Act (RCRA) heavy metals and semi-volatile constituents as defined by 40 CFR 261 and radiological parameters including gross alpha, gross beta, gross gamma, alpha-emitting isotopes and beta-emitting isotopes. Analysis of metals and semi-volatile constituents indicated no exceedances of regulatory limits. Analysis of radionuclides identified uranium and thorium and associated daughters. In addition 60Co, 99Tc, 226Rm, and 228Rm were identified. Most of the tower materials were determined to be low level radioactive waste. A small quantity was determined not to be radioactive, or could be decontaminated. The tower was dismantled October 2000 to January 2001 using a detailed step-by-step process to aid waste segregation and container loading. The volume of waste as packaged for treatment was approximately 1982 cubic meters (70,000 cubic feet). This volume was comprised of plastic ({approx}47%), wood ({approx}38%) and asbestos transite ({approx}14%). The remaining {approx}1% consisted of the fire protection piping (contaminated with lead-based paint) and incidental metal from conduit, nails and braces/supports, and sludge from the basin. The waste, except for the asbestos, was volume reduced via a private contract mechanism established by BJC. After volume reduction, the waste was packaged for rail shipment. This large waste management project successfully met cost and schedule goals.

  3. Hudson River cooling tower proceeding: Interface between science and law

    International Nuclear Information System (INIS)

    As the Hudson River power plant case proceeded, the regulatory ground shifted under the utility companies. At first, the US Environmental Protection Agency (EPA) contended that the utilities should build expensive closed-cycle cooling towers at three plants to minimize the plants' discharge of heated effluents to the river. When the formal hearing began, however, EPA claimed that cooling towers were needed to minimize the number of organisms impinged at and entrained through the plants. The Hudson River proceeding became a policy dispute over what the appropriate standard of environmental conduct should be, instead of a determination of whether a standard had been met or not. Such policy issues, which arise when legal precedent has yet to be developed for new laws like the Clean Water Act, are better addressed by a rule-making proceeding than by the adjudicatory hearing format used in the Hudson case. A rule-making proceeding would have markedly shortened the Hudson deliberations, probably without substantive change in the final settlement, and is recommended for future cases in which ambiguity in legislation or the lack of precedent has left policy matters unresolved. 2 refs

  4. Sampling and detection of Legionella pneumophila aerosols generated from an industrial cooling tower

    Energy Technology Data Exchange (ETDEWEB)

    Ishimatsu, Sumiyo; Hori, Hajime [University of Occupational and Environmental Health, Kitakyushu (Japan). Dept. of Environmental Management; Miyamoto, Hiroshi [University of Occupational and Environmental Health, Kitakyushu (Japan). Dept. of Microbiology; Tanaka, Isamu [University of Occupational and Environmental Health, Kitakyushu (Japan). Dept. of Environmental Health Engineering; Yoshida, Shinichi [Kyusha Univ., Fukuoka (Japan). Dept. of Bacteriology

    2001-07-01

    Cooling tower water has frequently been cited as a source of infection in outbreaks of Legionnaires' disease. However, there have been few reports on the presence of legionellae in aerosols from cooling towers. This paper describes our use of an impinger or a six-stage microbial impactor for detecting legionellae in air around a cooling tower contaminated with L. pneumophila (1.2{+-}0.3x10{sup 5} CFU/100ml). Phosphate-buffered saline, Page's saline, 2% yeast extract solution and buffered yeast extract (BYE) broth were tested to evaluate their collection efficiency. These solutions were compared in laboratory experiments using an aerosol of L. pneumophila serogroup (SG) 1. Because BYE broth was the most efficient and storable collecting fluid among them, it was used for outdoor air sampling. In the outdoor air sampling, aerosolized L. pneumophila SG 6 was detected in the air around the cooling tower by the impinger (0.09 CFU/1. air). No legionellae were detected by the impactor with Legionella-selective agar plates (WYO{alpha}) because the plates were overgrown with fungi. Repetitive element PCR (rep-PCR) and arbitrarily primed PCR (AP-PCR) were employed to assess the epidemiological relationship among Legionella isolates from the air sample and the cooling tower water samples. L. pneumophila SG 6 isolated from the aerosols produced rep-PCR and AP-PCR fingerprints identical to those of L. pneumophila SG 6 strains from the cooling tower water, suggesting that the bacterium was aerosolized from the cooling tower. (author)

  5. Flue gas injection control of silica in cooling towers.

    Energy Technology Data Exchange (ETDEWEB)

    Brady, Patrick Vane; Anderson, Howard L., Jr.; Altman, Susan Jeanne

    2011-06-01

    Injection of CO{sub 2}-laden flue gas can decrease the potential for silica and calcite scale formation in cooling tower blowdown by lowering solution pH to decrease equilibrium calcite solubility and kinetic rates of silica polymerization. Flue gas injection might best inhibit scale formation in power plant cooling towers that use impaired makeup waters - for example, groundwaters that contain relatively high levels of calcium, alkalinity, and silica. Groundwaters brought to the surface for cooling will degas CO{sub 2} and increase their pH by 1-2 units, possibly precipitating calcite in the process. Recarbonation with flue gas can lower the pHs of these fluids back to roughly their initial pH. Flue gas carbonation probably cannot lower pHs to much below pH 6 because the pHs of impaired waters, once outgassed at the surface, are likely to be relatively alkaline. Silica polymerization to form scale occurs most rapidly at pH {approx} 8.3 at 25 C; polymerization is slower at higher and lower pH. pH 7 fluids containing {approx}220 ppm SiO{sub 2} require > 180 hours equilibration to begin forming scale whereas at pH 8.3 scale formation is complete within 36 hours. Flue gas injection that lowers pHs to {approx} 7 should allow substantially higher concentration factors. Periodic cycling to lower recoveries - hence lower silica concentrations - might be required though. Higher concentration factors enabled by flue gas injection should decrease concentrate volumes and disposal costs by roughly half.

  6. Alternative geometry for cylindrical natural draft cooling tower with higher cooling efficiency under crosswind condition

    International Nuclear Information System (INIS)

    Highlights: • Alternative cross sections for natural draft cooling tower were proposed. • Numerical solution was applied to study thermal and hydraulic performances. • Thermal and hydraulic performances were assessed by comparative parameters. • Cooling tower with elliptical cross section had better thermal performance under crosswind. • It could successfully used at the regions with invariant wind direction. - Abstract: Cooling efficiency of a natural draft dry cooling tower may significantly decrease under crosswind condition. Therefore, many researchers attempted to improve the cooling efficiency under this condition by using structural or mechanical facilities. In this article, alternative shell geometry with elliptical cross section is proposed for this type of cooling tower instead of usual shell geometry with circular cross section. Thermal performance and cooling efficiency of the two types of cooling towers are numerically investigated. Numerical simulations show that cooling tower with elliptical cross section improves the cooling efficiency compared to the usual type with circular cross section under high-speed wind moving normal to the longitudinal diameter of the elliptical cooling tower

  7. Statistical multi-model approach for performance assessment of cooling tower

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Tian-Hong [School of Electrical and Information Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013 (China); Shieh, Shyan-Shu [Department of Occupational Safety and Health, Chang Jung Christian University, 71101 (China); Jang, Shi-Shang; Tseng, Wen-Hung [Chemical Engineering Department, National Tsing-Hua University, Hsin-Chu 30047 (China); Wu, Chan-Wei; Ou, Jenq-Jang [Energy and Air Pollution Control Section, New Materials Research and Development Dept., China Steel Corporation, Kaohsiung 80012 (China)

    2011-02-15

    This paper presents a data-driven model-based assessment strategy to investigate the performance of a cooling tower. In order to achieve this objective, the operations of a cooling tower are first characterized using a data-driven method, multiple models, which presents a set of local models in the format of linear equations. Satisfactory fuzzy c-mean clustering algorithm is used to classify operating data into several groups to build local models. The developed models are then applied to predict the performance of the system based on design input parameters provided by the manufacturer. The tower characteristics are also investigated using the proposed models via the effects of the water/air flow ratio. The predicted results tend to agree well with the calculated tower characteristics using actual measured operating data from an industrial plant. By comparison with the design characteristic curve provided by the manufacturer, the effectiveness of cooling tower can be obtained in the end. A case study conducted in a commercial plant demonstrates the validity of proposed approach. It should be noted that this is the first attempt to assess the cooling efficiency which is deviated from the original design value using operating data for an industrial scale process. Moreover, the evaluated process need not interrupt the normal operation of the cooling tower. This should be of particular interest in industrial applications. (author)

  8. An exergy analysis on the performance of a counterflow wet cooling tower

    International Nuclear Information System (INIS)

    Cooling towers are used to extract waste heat from water to atmospheric air. An energy analysis is usually used to investigate the performance characteristics of cooling tower. However, the energy concept alone is insufficient to describe some important viewpoints on energy utilization. In this study, an exergy analysis is used to indicate exergy and exergy destruction of water and air flowing through the cooling tower. Mathematical model based on heat and mass transfer principle is developed to find the properties of water and air, which will be further used in exergy analysis. The model is validated against experimental data. It is noted from the results that the amount of exergy supplied by water is larger than that absorbed by air, because the system produces entropy. To depict the utilizable exergy between water and air, exergy of each working fluid along the tower are presented. The results show that water exergy decreases continuously from top to bottom. On the other hand, air exergy is expressed in terms of convective and evaporative heat transfer. Exergy of air via convective heat transfer initially loses at inlet and slightly recovers along the flow before leaving the tower. However, exergy of air via evaporative heat transfer is generally high and able to consume exergy supplied by water. Exergy destruction is defined as the difference between water exergy change and air exergy change. It reveals that the cooling processes due to thermodynamics irreversibility perform poorly at bottom and gradually improve along the height of the tower. The results show that the lowest exergy destruction is located at the top of the tower

  9. Analysis of the evaporative towers cooling system of a coal-fired power plant

    OpenAIRE

    Lakovi? Mirjana S.; Lakovi? Slobodan V.; Banjac Miloš J.

    2012-01-01

    The paper presents a theoretical analysis of the cooling system of a 110 MW coal-fired power plant located in central Serbia, where eight evaporative towers cool down the plant. An updated research on the evaporative tower cooling system has been carried out to show the theoretical analysis of the tower heat and mass balance, taking into account the sensible and latent heat exchanged during the processes which occur inside these towers. Power plants which are using wet cooling towers fo...

  10. Scaling prediction and prevention in condenser cooling circuits with cooling towers

    International Nuclear Information System (INIS)

    The condenser cooling circuits are the place of a large number of chemicals reactions interacting with some other phenomena like scaling, dissolved gases stripping, additives injections, cooling tower evaporation, etc. The purpose of the present work is to reconcile the experimental data obtained on a pilot plant (1/145 000 scale) for nuclear cooling circuits with carbonate scale theoretical models. The theoretical scaling models currently available in scientific literature have been developed using laboratory data obtained under ideal conditions (quality controlled solutions, absence of total suspended solids, clean surfaces ...). The final goal is to provide a practical engineering tool, including thermodynamics and kinetics, for simulation and prevention of scaling phenomenon in nuclear cooling water circuits equipped with cooling towers. The simplified equations and the program structure have been presented in a previous work. In this paper we present the results of the application of a theoretical carbonate-scaling model to industrial purposes, calibration and validation of the model in order to adjust the results obtained from modeling to those obtained from experience. This numerical model is a very interesting tool to predict, in any configuration, discharge composition (temperature and chemistry), scaling rate and additive injections, in order to optimize costs, improve safety, respect the environment and increase operational performance. (author)

  11. Influence of wind on conditions of plumes at natural draft cooling towers

    International Nuclear Information System (INIS)

    It was the objective of this research project, to establish the influence of wind on the emission characteristics, the plume data at the top of cooling towers and on the dispersion of plumes in free atmosphere. Data from field-measurements on a natural draft wet cooling-tower were analyzed systematically, a model for the calculation of the plume characteristics was further developed, and the plume dispersion under different conditions was investigated by a model computation. Plume velocity and cooling air massflow show a minimum at a wind speed around 4 m/s. Their depression in this area of wind speed leads to an increase of the cold water temperature of the cooling tower and hence to a loss of power station efficiency. Temperature and humidity of plume have a maximum value in this area. Halving of wind velocity leads to doubling of the cross section area in the symmetry plane of the plume. (orig./HP)

  12. CFD MODELING AND ANALYSIS FOR A-AREA AND H-AREA COOLING TOWERS

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.; Garrett, A.; Bollinger, J.

    2009-09-02

    Mechanical draft cooling towers are designed to cool process water via sensible and latent heat transfer to air. Heat and mass transfer take place simultaneously. Heat is transferred as sensible heat due to the temperature difference between liquid and gas phases, and as the latent heat of the water as it evaporates. Mass of water vapor is transferred due to the difference between the vapor pressure at the air-liquid interface and the partial pressure of water vapor in the bulk of the air. Equations to govern these phenomena are discussed here. The governing equations are solved by taking a computational fluid dynamics (CFD) approach. The purpose of the work is to develop a three-dimensional CFD model to evaluate the flow patterns inside the cooling tower cell driven by cooling fan and wind, considering the cooling fans to be on or off. Two types of the cooling towers are considered here. One is cross-flow type cooling tower located in A-Area, and the other is counterflow type cooling tower located in H-Area. The cooling tower located in A-Area is mechanical draft cooling tower (MDCT) consisting of four compartment cells as shown in Fig. 1. It is 13.7m wide, 36.8m long, and 9.4m high. Each cell has its own cooling fan and shroud without any flow communications between two adjacent cells. There are water distribution decks on both sides of the fan shroud. The deck floor has an array of about 25mm size holes through which water droplet falls into the cell region cooled by the ambient air driven by fan and wind, and it is eventually collected in basin area. As shown in Fig. 1, about 0.15-m thick drift eliminator allows ambient air to be humidified through the evaporative cooling process without entrainment of water droplets into the shroud exit. The H-Area cooling tower is about 7.3 m wide, 29.3 m long, and 9.0 m high. Each cell has its own cooling fan and shroud, but each of two corner cells has two panels to shield wind at the bottom of the cells. There is some degree of flow communications between adjacent cells through the 9-in gap at the bottom of the tower cells as shown in Fig. 2. Detailed geometrical dimensions for the H-Area tower configurations are presented in the figure. The model was benchmarked and verified against off-site and on-site test results. The verified model was applied to the investigation of cooling fan and wind effects on water cooling in cells when fans are off and on. This report will discuss the modeling and test results.

  13. French operational experience on fouling problems (algae, bryozoas) in cooling towers

    International Nuclear Information System (INIS)

    Electricite de France (EDF) has committed itself to the adoption of some technical procedures and the development of environmental research actions in the fields of water, air, noise, fauna, flora, landscapes and the occupation of space. Continuous chlorination has been replaced by massive chlorination with the blowdown of the cooling tower closed, which prevents free chlorine from being released into the environment. In addition, massive chlorination is only undertaken when a fouling threshold has been reached. However, other arms need to be introduced by EDF by reason of major biological growth (algea, bryozoa) which remains unaffected by sodium hypochlorite solution injections. This paper presents the findings of studies conducted by the Aquatic and Atmospheric Environment Department on the optimization of the injections of sodium hypochlorite solution and the infestation of cooling towers by algae and bryozoa. It is a part of the inter-directorate working group's mandate relating to conditioning of the circulation water cooling towers

  14. The status and development prospects of cooling tower design from the point of view of various environmental effects

    International Nuclear Information System (INIS)

    The manufacturers of wet and dry cooling towers are striving to develop plants for discharging waste heat into the atmosphere which are as operationally safe and favourable from the environmental point of view as possible. Using as an example plants which have been tendered and designed for water cooling, the paper indicates how the cooling tower design can be adapted to suit the particular environmental protection requirements of the location. (orig.)

  15. Computer optimization of dry and wet/dry cooling tower systems for large fossil and nuclear power plants

    International Nuclear Information System (INIS)

    This study determined the cost of dry cooling compared to the conventional cooling methods. Also, the savings by using wet/dry instead of all-dry cooling were determined. A total optimization was performed for power plants with dry cooling tower systems using metal-finned-tube heat exchangers and surface condensers. The optimization minimizes the power production cost. The program optimizes the design of the heat exchanger and its air and water flow rates. In the base case study, the method of replacing lost capacity assumes the use of gas turbines. As a result of using dry cooling towers in an 800 MWe fossil plant, the incremental costs with the use of high back pressure turbine and conventional turbine over all-wet cooling are 11 and 15%, respectively. For a 1200 MWe nuclear plant, these are 22 and 25%, respectively. Since the method of making up lost capacity depends on the situation of a utility, considerable effort has been placed on testing the effects of using different methods of replacing lost capacity at high ambient temperatures by purchased energy. The results indicate that the optimization is very sensitive to the method of making up lost capacity. It is, therefore, important to do an accurate representation of all possible methods of making up capacity loss when optimizating power plants with dry cooling towers. A solution for the problem of losing generation capability by a power plant due to the use of a dry cooling tower is to supplement the dry tower during the hours of peak ambient temperatures by a wet tower. A separate wet/dry cooling tower system with series tower arrangement was considered in this study, and proved to be an economic choice over all-dry cooling where some water is available but supplies are insufficient for a totally evaporative cooling tower

  16. Cooling tower environmental impact prediction at inland nuclear power plant

    International Nuclear Information System (INIS)

    As a heat dissipation system, natural-draft cooling tower is usually used for inland nuclear power plant. The waste heat of plant is transferred to atmosphere primarily by evaporating, which will bring out the potential adverse impacts,including visible plume, shadow of plume,ground deposition of drift droplet and noise. In this paper, the environmental impact prediction model of cooling tower, based on SACTI program recommended by NRC, was used to predict impacts of current three inland nuclear power sites (Hunan, Hubei and Anhui provinces). To illustrate the compatibility of SACTI in China, the prediction results were compared with GGNS power station in U.S. (authors)

  17. Calculation of cooling tower plumes for high pressure wintry situations

    International Nuclear Information System (INIS)

    The diffusion of the plumes of the projected nuclear power plants at Kaiseraugst and Schwoerstadt, during high pressure wintry conditions, has been examined using a mathematical model to simulate the plumes. For these calculations, microaerological measurements were made in the proximity of Kaiseraugst and Schwoerstadt. These give a typical image of the weather during high pressure wintry conditions, which is normally associated with an inversion, sometimes strong, at a low height. Dry cooling towers with natural draught, which offer an alternative solution to the wet cooling towers proposed for Kasieraugst, are examined equally. (Auth./G.T.H.)

  18. Results of a cooling tower performance test and analysis project

    International Nuclear Information System (INIS)

    Recent measurements of the heat and mass transfer characteristics on cooling tower fills (packings) are reported. Results include laboratory-quality data from a 1.5 MW (thermal) facility constructed for this effort, and corresponding full-scale data from 10 MW (thermal) cooling tower cells. State-of-the-art models of the heat and mass transfer process that vary in refinement and complexity are described. These models, which are being used to correlate the data, are assessed. This assessment is aimed at improvement in predictive ability compared to using conventional Merkel analysis

  19. Cooling tower practice in Germany: state of the art

    International Nuclear Information System (INIS)

    Development in design and construction of natural draught cooling towers that has taken place in Germany is discussed. Research has been concentrated on theory and analysis of shells, on acting forces, especially on wind effects, on buckling behavior and constructional problems. An approximate earthquake analysis allows a quick estimation of seismic response. The earthquake analysis is carried out by the response-spectrum-method. All design methods develop construction methods minimizing the imperfections and their control and correction during the erection process. It is shown how by arranging stiffening rings the buckling resistance and the lowest natural frequency of this new generation of cooling towers can be improved. 13 refs

  20. Study of the comparative costs of five wet/dry cooling tower concepts

    Energy Technology Data Exchange (ETDEWEB)

    Zaloudek, F.R.; Allemann, R.T.; Faletti, D.W.; Johnson, B.M.; Parry, H.L.; Smith, G.C.; Tokarz, R.D.; Walter, R.A.

    1976-09-01

    The projected cost of five alternative dry/wet power plant heat rejection concepts was studied under conditions imposed by hypothetical use in association with the San Juan Plant Unit 3, a 550-MWe facility currently under construction near the ''Four Corners'' area of New Mexico. The five alternative concepts were: integrated dry/wet tower; separate dry and wet towers; metal fin-tube induced draft tower with deluge water augmentation; plastic heat exchanger tower with deluge water augmentation, and metal fin-tube/deluge augmentation tower with an intermediate ammonia evaporation-condensation condenser and the cooling tower. The integrated dry/wet tower concept, already chosen for service at San Juan Unit 3, was included for reference purposes. All concepts were conceptually designed and estimated using the same bases and employing uniform practices. Each concept was assumed to use all water allocated for consumptive use in Unit 3. The cost estimates obtained showed the following descending order of ''comparable capital cost'': separate dry/wet; metal fin-tube/deluge; integrated dry/wet; plastic tube/deluge; and metal fin-tube/deluge/ammonia. The results indicate that two of the advanced concepts considered, i.e., the plastic tube/deluge concept and the metal fin tube/deluge/ammonia concept, can possibly reduce the overall costs of dry/wet cooling under conditions imposed by the site considered. It was recommended that these two concepts receive additional attention by the ERDA Dry Cooling Tower Program and industry to further quantify their potential benefits and demonstrate their performance and reliability.

  1. Performance prediction of wet cooling tower using artificial neural network under cross-wind conditions

    International Nuclear Information System (INIS)

    This paper describes an application of artificial neural networks (ANNs) to predict the thermal performance of a cooling tower under cross-wind conditions. A lab experiment on natural draft counter-flow wet cooling tower is conducted on one model tower in order to gather enough data for training and prediction. The output parameters with high correlation are measured when the cross-wind velocity, circulating water flow rate and inlet water temperature are changed, respectively. The three-layer back propagation (BP) network model which has one hidden layer is developed, and the node number in the input layer, hidden layer and output layer are 5, 6 and 3, respectively. The model adopts the improved BP algorithm, that is, the gradient descent method with momentum. This ANN model demonstrated a good statistical performance with the correlation coefficient in the range of 0.993-0.999, and the mean square error (MSE) values for the ANN training and predictions were very low relative to the experimental range. So this ANN model can be used to predict the thermal performance of cooling tower under cross-wind conditions, then providing the theoretical basis on the research of heat and mass transfer inside cooling tower under cross-wind conditions. (authors)

  2. Numerical analysis of crosswind effect on wet cooling tower aerodynamic field

    International Nuclear Information System (INIS)

    Based on CFD code FLUENT, three-dimensional numerical analyses were carried out for natural draft wet cooling tower under crosswind conditions.Sensitivity analyses to parameters such as ambient crosswind velocity profile and water droplet equivalent diameter validated the adopted numerical model. The effect of crosswind on wet cooling tower inner and outer aerodynamic field and tower internal heat and mass transfer performance were investigated numerically. The results show that crosswind causes the increase of air inflow relative departure degree and induces horizontal air mass flow rate which improves rain zone heat and mass transfer but reduces tower vertical air mass flow rate, and then produces an unfavorable effect on fill zone and increases outflow water temperature. The analyses about air inflow relative departure degree show that improving the air inflow aerodynamic field can reduce the unfavorable effect of crosswind on the circumference distribution of air inlet air radial velocity and then improve the total cooling performance of wet cooling tower under crosswind conditions. (authors)

  3. A construction method of reinforced-concrete very high stacks and natural draft cooling towers

    International Nuclear Information System (INIS)

    The new Shimizu flex-lip system was developed by the Shimizu Construction Co., Ltd. for constructing very high (about 200 m) towers made of reinforced concrete. Utilizing this system, towers of any shape, circular, triangular, square and polygonal, can be constructed. The wall thickness can be varied from 200 mm to 1 m. The diameter of towers can be enlarged from 3 m to any valve and the inclination of tower walls can be designed in any way between +1/5 and -1/5. The advantage of this system is to use the jack down mechanism, to test concrete strength without sampling, to reduce the connections of reinforcing steel bars and to adopt the continuous, and to use automatic measuring system using laser for checking up positional error. The design and analysis of high tower structures were systemized and automated with the development of the flex-lip construction method. The several past records of having applied this method to industrial areas are shown. As for natural draft cooling towers, the Shimizu jump-up system has been studied for the cooling water capacity of 60,000 m3/h. The towers are 120 m high, 110 m in diameter at the bottom and 65 m in diameter at the top. The advantage of this construction method, the plan of concrete jump-up and the construction test are explained. (Nakai, Y.)

  4. EDF's ageing management program for cooling towers

    International Nuclear Information System (INIS)

    EDF operates a large fleet of cooling towers for its thermal and nuclear plants. Proactive maintenance strategies require ranking the towers according to the risk of failure and the observed damage. The ranking includes monitoring data such as: foundation settlements, material properties, quantified crack patterns, shell deformation, meteorological data, and corrosion. The numerical tool suite includes a finite element analysis of each tower under thermal and mechanical loadings and a corrosion predicting tool, based on carbonation. The first module computes the behavior of cooling towers under five types of loading: soil differential settlement, self-weight, moisture transport, temperature and wind. By comparison with the ultimate resisting capacity of the reinforced concrete cross section, a risk index map is produced for each tower. This risk index is used to rank the cooling towers and then to identify which structures should be monitored more closely or reinforced - if needed - first in the case of an extended operating life. The second module aims to anticipate the corrosion depth of reinforcement steel of the towers in the future. Examination of the existing carbonation is currently done for each structure and evolution of the carbonation depth is computed so as to predict with reasonable assurance when carbonation reaches the rebars. A prediction of the eventual cross-section loss of rebars is then made for long term analysis (i.e. up to 60 years of operating life). When corrosion is predicted the first module takes into account this loss and computes the behavior of the predicted corrosion damaged structure under the same loadings. (authors)

  5. Add helper cooling towers to control discharge temperatures

    International Nuclear Information System (INIS)

    This article describes the retrofitting of helper cooling towers to the Crystal River energy complex to reduce thermal pollution to the Gulf of Mexico. The topics of the article include the design concept, evaluation of design alternatives, a project description, economic evaluation, marine organism control, power requirements, and auxiliary systems

  6. Cooling tower improvement cuts costs at Illinois Power

    International Nuclear Information System (INIS)

    The inevitable deregulation of the electric utility industry has caused many electric utility companies to look closely at their existing assets with a view to reducing unit' production costs. Illinois Power has identified improving cooling tower performance at Unit 6 of its Havana station as an economically attractive option. (author)

  7. Effects of wet cooling towers on weather and climatic conditions

    International Nuclear Information System (INIS)

    Type and efficiency of the occuring process are treated in connection with the important external conditions. The description of the direct effects and the indirect as well leads to the conclusion that thorough investigations of environmental influences by wet cooling towers have to be carried out in a few particular cases only. (orig.)

  8. Optimization design of solar enhanced natural draft dry cooling tower

    International Nuclear Information System (INIS)

    Highlights: • We proposed a cost model for solar enhanced natural draft dry cooling tower. • We proposed an optimization scheme for this new cooling system. • We optimally designed one for a 50 MW EGS geothermal plant as a demonstration. • Results proved its economic advantages for EGS geothermal application. - Abstract: This paper proposed an optimization scheme for solar enhanced natural draft dry cooling tower design, in which a detailed cost model was proposed including capital, labour, maintenance and operation costs of each component. Based on the developed cost model, the optimal design option can be identified in terms of the relatively lower annual cost and the relatively higher total extra income over the Solar Enhanced Natural Draft Dry Cooling Tower (SENDDCT) lifetime. As a case study, a SENDDCT was optimally designed to meet the cooling demand for a 50 MW geothermal power plant with Engineered Geothermal System (EGS) technology. The results showed that the optimized SENDDCT not only has better cooling performance during the daytime but also is a cost effective option for EGS geothermal power plants

  9. Construction of a 146m height stay-structured cooling tower

    International Nuclear Information System (INIS)

    Construction of cooling tower for 300 MW NPP with the THTR-300 type reactors has been described. Dry stay-structured cooling tower with capacity 31700 m3/hr is designed for water cooling from 38.4 to 26.5 deg C under the pressure of 10.1 kPa and at the environment temperature 12 deg C. The assessed period of operation is 50 years. The tower height is 146 m and the foundation diameter is 141 m. The construction is designed for wind loading exceeding by a factor of 1.5 the loading 1550 H/m2 in the areas of the smallest transverse cross section. Under the loading the fluidity limit, corresponding to relative elongation of element of 0.02%, will not be surpassed in any of the steel elements. A central ferroconcrete pylon 180 m high and 6.6 m in diameter serves as the tower support. One upper and two intermediate rings are suspended to the pylon by ropes. To the upper ring the stay-structured net is fixed, which is lined from the inner side with corrugated sheets 1 mm thick; the lining area is 38000 m2. As compared with conventional cooling towers the one described is less metal-consuming (approximately 30%), it is characterized by increased resistance of structure to wind and seismic loadings, increased plant completeness of its elements, and it can be erected not using cranes

  10. Study the factors on which efficiency of cooling tower can be critically acclaimed (A case Study

    Directory of Open Access Journals (Sweden)

    Krishna S. Vishwakarma

    2015-04-01

    Full Text Available Water cooling is widely used in many industrial processes to control heat removal from a hot material surface. In order to control the temperature distributions, a deeper understanding more accurate estimation of spray heat transfer rates is needed. In a new technique combining experiment and computational modeling developed for water cooling. It is better to understand the heat transfer mechanisms from the combustion gases to the cooling water and then from the cooling water to the environment. To meet this need a logic tree is developed to provide guidance on how to balance and identify problems within cooling system and schedule appropriate maintenance. Fluid dynamics, Thermodynamics and Heat transfer are involved in developing a cooling system model and the operation is familiar to the general operating companies. There will be the comparison and parametric investigation of the cooling system model in the logic tree and the results are summarized as tables and charts. The objective is to identify the several ways of improving efficiency of cooling tower. In this study we are doing the comparison ofsome calculations regarding the cooling tower.

  11. New natural draft cooling tower of 200 m of height

    Energy Technology Data Exchange (ETDEWEB)

    Busch, D. [RWE Solution AG, Essen (Germany); Harte, R. [University of Wuppertal (Germany). Department of Civil Engineering; Kraetzig, W.B. [Ruhr-University Bochum (Germany). Department of Civil Engineering; Montag, U. [Kraetzig and Partner Engineering Consultants, Bochum (Germany)

    2002-12-01

    In the years 1999 to 2001 a new natural draft cooling tower has been built at the RWE power station at Niederaussem, with 200 m elevation the highest cooling tower world-wide. For many reasons, such structures can not be designed merely as enlargement of smaller ones, on the contrary, it is full of innovative new design elements. The present paper starts with an overview over the tower and a description of its geometry, followed by an elucidation of the conceptual shape optimization. The structural consequences of the flue gas inlets through the shell at a height of 49 m are explained as well as the needs for an advanced high performance concrete for the wall and the fill construction. Further, the design and structural analysis of the tower is described with respect to the German codified safety concept for these structures. Finally, the necessity of extended durability of this tower is commented, the durability design concept is explained in detail and illustrated by virtue of a series of figures. (author)

  12. Biocide usage in cooling towers in the electric power and petroleum refining industries

    Energy Technology Data Exchange (ETDEWEB)

    Veil, J.; Rice, J.K.; Raivel, M.E.S.

    1997-11-01

    Cooling towers users frequently apply biocides to the circulating cooling water to control growth of microorganisms, algae, and macroorganisms. Because of the toxic properties of biocides, there is a potential for the regulatory controls on their use and discharge to become increasingly more stringent. This report examines the types of biocides used in cooling towers by companies in the electric power and petroleum refining industries, and the experiences those companies have had in dealing with agencies that regulate cooling tower blowdown discharges. Results from a sample of 67 electric power plants indicate that the use of oxidizing biocides (particularly chlorine) is favored. Quaternary ammonia salts (quats), a type of nonoxidizing biocide, are also used in many power plant cooling towers. The experience of dealing with regulators to obtain approval to discharge biocides differs significantly between the two industries. In the electric power industry, discharges of any new biocide typically must be approved in writing by the regulatory agency. The approval process for refineries is less formal. In most cases, the refinery must notify the regulatory agency that it is planning to use a new biocide, but the refinery does not need to get written approval before using it. The conclusion of the report is that few of the surveyed facilities are having any difficulty in using and discharging the biocides they want to use.

  13. Air-Water Cooling in the Bubble Column

    Directory of Open Access Journals (Sweden)

    Medvedev Gennadiy

    2015-01-01

    Full Text Available The processes of air-water interaction are in general use in engineering. Air and water tend to be the most popular heat-storage media. In particular, the process of air-water cooling is widely used in water cooling at thermal electric power stations in cooling towers, in systems of in-plant water recirculation, etc.

  14. Potential weather modification caused by waste heat release from large dry cooling towers

    International Nuclear Information System (INIS)

    A numerical model of a cooling tower plume is employed to study the possible atmospheric effects of thermal plumes from natural draft dry cooling towers. Calculations are performed for both single and multiple towers, each of which can dissipate the waste heat from a nominal 1000 MWe power generating unit, and the results are compared with those for wet cooling towers associated with plants of the same generating capacity. Dry cooling tower plumes are found to have a higher potential for inducing convective clouds than wet cooling tower plumes, under most summertime meteorological conditions. This is due to the fact that both the sensible heat and momentum fluxes from a dry tower in summer are approximately one order of magnitude larger than those from a wet cooling tower

  15. Anomalous snowfall caused by natural-draft cooling towers

    International Nuclear Information System (INIS)

    Scattered reports of significant amounts of snow anomalously produced by cooling-tower plumes suggest that this process may be of importance. This conclusion is supported by study of high-resolution satellite images. Tabulation of a number of aerial observations of plumes at subfreezing temperatures indicates that a plume is likely to produce measurable snow if its temperature is colder than -130C and the saturation deficit of the ambient air is less than 0.5 g m-3. These factors are important because they affect the rates of nucleation and growth of ice particles. The rate of mixing between plume and ambient air is also important because it affects the rate of evaporation within the plume, which in turn determines the length of time available for snow particles to grow large enough to fall out. These empirically derived criteria were tested using a numerical model of cloud microphysics that simulates the most important processes of transfer of water substance between vapor, liquid, and ice, including nucleation and development of particle-size spectra. Dynamic processes were specified, not modeled. Among the many quantities computed is the flux density of snow at the base of the plume. From this, together with average fallspeed and horizontal wind speed, one can compute the amount and pattern of snowfall at the ground

  16. Synthetic image generation of factory stack and cooling tower plumes

    Science.gov (United States)

    Kuo, Shiao D.; Schott, John R.

    1997-07-01

    A new model for generating synthetic images of plumes has been developed using a radiometrically based ray-tracing algorithm. Existing plume models that describe the characteristics of the plume (constituents, concentration, particulate sizing, and temperature) are used to generate AutoCAD models for input into the code. The effects of scattered light using Mie theory and radiative transfer, as well as thermal self-emission/absorption from within the plume, are modeled for different regions of the plume. The ray-tracing accounts for direct sunlight, scattered skylight, reflected sunlight from the background, and thermal self-emission from both the atmosphere and background. Synthetic generated images of a cooling tower plume, composed of water droplets, and a factor stack plume, composed of methyl chloride, are produced for visible, MWIR, and LWIR bands. Images of the plume from different view angles are also produced. Observations are made on the interaction between the plume and its background and possible effects for remote sensing. Images are made of the methyl chloride plume in which the concentration and temperature are varied to determine the sensitivity of the radiance reaching the sensor.

  17. Study on Characteristics of Special Turbine in Hydrodynamic Cooling Tower

    Directory of Open Access Journals (Sweden)

    Li Yanpin

    2012-11-01

    Full Text Available Today a special type of hydraulic turbine is used to replace electromotor to drive the fan in hydrodynamic cooling tower. This is a brand new turbine application. At present, systematic researching about the special turbine has still not been seen. The energy consumption of the electromotor is saved entirely because the power source comes from the surplus energy of circulating water system. But the special turbine works in a series of pressure flow system, its flow characteristic, working characteristics and regulative characteristics different from conventional power turbine. This study introduces the theory analysis and experimental study on these characteristics. The research shows that special turbine has more complex flow characteristics and the turbine-fan unit has good self-adaptive characteristics and regulative characteristics. When the turbine is not in its optimal condition we can regulate it to a proper condition by adjusting the guide glade and the angle of the fan's vane or replacing the diameter of fan. These are never been found.

  18. Numerical research of a super-large cooling tower subjected to accidental loads

    International Nuclear Information System (INIS)

    With the continued development of nuclear power plants, more and more super-large cooling towers are to be built in China and around the world. For the safe operation of nuclear power plants, research work has been done on the causes of collapse of cooling towers, collapse modes and the secondary disasters caused by the collapse of cooling towers. However, the collapse modes and the ground vibration induced by the collapse of cooling towers subjected to the accidental loads have not been fully understood. This paper has been focused on the modes and mechanisms behavior of the collapse of cooling towers subjected to accidental loads. Meanwhile, prediction of the ground vibration due to the collapse of the cooling towers has also been completed in a parallel project. Using dynamic finite element program LS-DYNA, a 3D finite element model for a super-large cooling tower was developed and the nonlinear material models were incorporated. In this paper, four types of accidental loads were considered to trigger the collapse or local failure of the tower, including vehicle collision, airplane impact, local explosion and missile attack. It was found that vehicle collision, missile attack and small TNT equivalent explosives (2 kg, 20 kg, 200 kg) might result in local failure of the cooling tower, however, the tower can still keep stable. On the other hand, large TNT equivalent explosives (2000 kg, 4500 kg) could cause severe damages in the inclined columns of the cooling tower, and lead to progressive collapse of the entire cooling tower. The two kinds of TNT equivalent explosives caused the same collapse mode while the collapsing duration was different. The airplane impacted at the throat of the cooling tower caused the local failure of shell structure of the tower, and then the progressive collapse of the cooling tower happened due to the gravitational action. The resulting collapse mode was different from that triggered by the local explosion

  19. Numerical research of a super-large cooling tower subjected to accidental loads

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yi; Lin, Feng [Department of Building Engineering, Tongji University, Shanghai 200092 (China); Gu, Xianglin, E-mail: gxl@tongji.edu.cn [Department of Building Engineering, Tongji University, Shanghai 200092 (China); Lu, Xiaoqin [Guangdong Electric Power Design Institute, Guangzhou 510660 (China)

    2014-04-01

    With the continued development of nuclear power plants, more and more super-large cooling towers are to be built in China and around the world. For the safe operation of nuclear power plants, research work has been done on the causes of collapse of cooling towers, collapse modes and the secondary disasters caused by the collapse of cooling towers. However, the collapse modes and the ground vibration induced by the collapse of cooling towers subjected to the accidental loads have not been fully understood. This paper has been focused on the modes and mechanisms behavior of the collapse of cooling towers subjected to accidental loads. Meanwhile, prediction of the ground vibration due to the collapse of the cooling towers has also been completed in a parallel project. Using dynamic finite element program LS-DYNA, a 3D finite element model for a super-large cooling tower was developed and the nonlinear material models were incorporated. In this paper, four types of accidental loads were considered to trigger the collapse or local failure of the tower, including vehicle collision, airplane impact, local explosion and missile attack. It was found that vehicle collision, missile attack and small TNT equivalent explosives (2 kg, 20 kg, 200 kg) might result in local failure of the cooling tower, however, the tower can still keep stable. On the other hand, large TNT equivalent explosives (2000 kg, 4500 kg) could cause severe damages in the inclined columns of the cooling tower, and lead to progressive collapse of the entire cooling tower. The two kinds of TNT equivalent explosives caused the same collapse mode while the collapsing duration was different. The airplane impacted at the throat of the cooling tower caused the local failure of shell structure of the tower, and then the progressive collapse of the cooling tower happened due to the gravitational action. The resulting collapse mode was different from that triggered by the local explosion.

  20. Effects of wet cooling towers on weather and climate

    International Nuclear Information System (INIS)

    According to all the facts known until now, it may be stated that with the current cooling powers up to about 3,000 MW, the waste heat released through wet cooling towers results in no disadvantageous consequences for the environment. This is also valid for the concentration of several cooling towers of comparable size. Small changes of individual meteorological elements in the immediate neighborhood can no more be considered a hazard for the environment than negligible increases of temperature and rainfall in large cities and industrial agglomerations, known since a long time ago. It therefore seems justified to no longer consider the waste heat emission of large cooling towers set up in a flat, well ventilated terrain as an important part in the official licensing procedure and to carry out the time-consuming efficiency calculations only in individual cases or with especially unfavorable ground conditions. Climatic effects of a larger extent cannot be excluded if by application of higher cooling powers and concentration of groups of power stations the energy supply to the atmosphere occurs on larger areas and with higher vertical energy flows. Until now, the long-term effects on the regional climate which may arise as a consequence of the vapor release of a larger number of wet cooling plants by a change of the low-energy radiation conversion in the atmospheric boundary layer, cannot be assessed. By this mechanism lasting changes of the temperature level, the atmospheric stratifications, and the cloud climatology will be possible by means of variations of the conditions of insulation and emission of radiation. (orig./HP)

  1. A numerical study of interacting buoyant cooling-tower plumes

    Science.gov (United States)

    Bornoff, R. B.; Mokhtarzadeh-Dehghan, M. R.

    The compact design of mechanical cooling towers necessitates that the plumes are issued into the cross-wind in close proximity. An improved understanding of the interaction of adjacent plumes is therefore required for better design of such cooling towers, which may lead to a reduction in their environmental impact. This paper presents the results of a numerical investigation into the interaction of two adjacent plumes in a cross-flow. The numerical model simulates small-scale wind tunnel experiments of a cooling tower arrangement. The computations are performed for three-dimensional, turbulent, buoyant and interacting plumes, and for a single plume for comparison. Two double-source arrangements, namely, tandem and side-by-side, with respect to the oncoming atmospheric boundary layer are considered. A low Reynolds number k- ? turbulence model is used with two discretisation schemes, hybrid and QUICK, and the results are compared. Comparisons are also made with the experimental results. The results show that the interaction of side-by-side plumes is dominated by the interaction of the rotating vortex pairs within the plumes. A tandem source arrangement leads to early merging and efficient rise enhancement. Comparisons of the predicted results with experimental data show good agreement for the plume rise.

  2. Comparison of methods for measurement of cooling tower drift

    Science.gov (United States)

    Golay, M. W.; Glantschnig, W. J.; Best, F. R.

    An international comparison of methods for measurement of cooling tower drift has been performed at the Massachusetts Institute of Technology. Participants from Belgium, the United States and the Federal Republic of Germany participated in measurements of a spectrum of test environments, which span the range of cases which would typically be encountered in operating cooling towers. The environments differed according to droplet mass flux, droplet size distribution and gas speed. A wind tunnel was built to provide the various test environments, and a special optical drift measurement system was built to permit simultaneous monitoring of the environment sampled in the tests. Cases tested included both mechanical and natural draft cooling tower environments. Among the types of instruments tested are the pulsed laser light scattering system (PILLS), sensitive paper and other sensitive surface droplet impaction systems, isokinetic drift mass flux measurement systems and photographic systems. The results indicate that the instruments tested vary widely in their capabilities, with droplet sizing instruments being more effective in low load, small droplet size spectrum situations, and isokinetic mass and chemical assay techniques being most accurate in high load, large droplet distribution cases. Instruments relying upon thermodynamic state measurements in most cases agreed mutually within an order of magnitude. Their major source of error is believed to arise in the measurement of the gas stream relative humidity. This quantity is necessary for inferring the drift mass flux from the measurement provided by such instruments, which is the mixture saturation deficit or excess. For these tests the relative humidity was typically ? 98%.

  3. Vibration Analysis of a Cooling Fan Gear Reducer of the Secondary Cooling Tower in HANARO

    International Nuclear Information System (INIS)

    HANARO is an open-tank-in-pool-type Korean research reactor that generates 30MW of thermal power. It differs from power plant reactor in that the heat generated by HANARO is exhausted into the atmosphere through a secondary cooling tower, thus maintaining the core temperature constant. During every monthly inspection of the cooling tower, large vibrations that exceeded the permissible limit were observed at cooling fan gear reducer No. 4 of the cooling tower. The purpose of this study is to identify the origin of the large vibration and to repair it. FFT spectrum analysis is performed to identify the part that caused the large vibration. The results of the frequency analysis showed that the vibration frequency was 354 Hz, which is twice the natural frequency of the pinion gear. A check of the pinion gear revealed that there was a crack on the surface of the pinion gear. After the gear was replaced, the reducer operated normally

  4. Operational cost minimization in cooling water systems

    Scientific Electronic Library Online (English)

    M.M., Castro; T.W., Song; J.M., Pinto.

    2000-12-01

    Full Text Available In this work, an optimization model that considers thermal and hydraulic interactions is developed for a cooling water system. It is a closed loop consisting of a cooling tower unit, circulation pump, blower and heat exchanger-pipe network. Aside from process disturbances, climatic fluctuations are [...] considered. Model constraints include relations concerning tower performance, air flowrate requirement, make-up flowrate, circulating pump performance, heat load in each cooler, pressure drop constraints and climatic conditions. The objective function is operating cost minimization. Optimization variables are air flowrate, forced water withdrawal upstream the tower, and valve adjustment in each branch. It is found that the most significant operating cost is related to electricity. However, for cooled water temperatures lower than a specific target, there must be a forced withdrawal of circulating water and further makeup to enhance the cooling tower capacity. Additionally, the system is optimized along the months. The results corroborate the fact that the most important variable on cooling tower performance is not the air temperature itself, but its humidity.

  5. Operational cost minimization in cooling water systems

    Directory of Open Access Journals (Sweden)

    Castro M.M.

    2000-01-01

    Full Text Available In this work, an optimization model that considers thermal and hydraulic interactions is developed for a cooling water system. It is a closed loop consisting of a cooling tower unit, circulation pump, blower and heat exchanger-pipe network. Aside from process disturbances, climatic fluctuations are considered. Model constraints include relations concerning tower performance, air flowrate requirement, make-up flowrate, circulating pump performance, heat load in each cooler, pressure drop constraints and climatic conditions. The objective function is operating cost minimization. Optimization variables are air flowrate, forced water withdrawal upstream the tower, and valve adjustment in each branch. It is found that the most significant operating cost is related to electricity. However, for cooled water temperatures lower than a specific target, there must be a forced withdrawal of circulating water and further makeup to enhance the cooling tower capacity. Additionally, the system is optimized along the months. The results corroborate the fact that the most important variable on cooling tower performance is not the air temperature itself, but its humidity.

  6. Modeling of heat transfer in cooling towers with natural convection.

    Czech Academy of Sciences Publication Activity Database

    Zuniga-Gonzalez, Israel; Maršík, František

    Gdansk : IFFM Publishers, 2005 - (Mikielewicz, J.; Butrymowicz, D.; Trela, M.; Cie?li?ski, J.), s. 585-592 ISBN 83-88237-90-X. [ HEAT 2005 : International Conference on Transport Phenomena in Multiphase Systems. Gdansk (PL), 26.06.2005-30.06.2005] R&D Projects: GA ?R GA101/02/0364; GA ?R(CZ) GA101/05/2536 Institutional research plan: CEZ:AV0Z20760514 Keywords : cooling tower * heat transfer * evaporative cooling Subject RIV: BK - Fluid Dynamics

  7. A numerical study for performance analysis and design of a counterflow type cooling tower

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.Y.; Lee, J.H. [Chung-Ang University Graduate School, Seoul (Korea, Republic of); Choi, Y.K.; Ryou, H.S. [Chung-Ang University, Seoul (Korea, Republic of)

    1998-04-01

    A numerical study for performance analysis of a counterflow type natural draft cooling tower has been performed using the finite volume method with non-orthogonal body fitted, non-staggered grid system. For solving the coupling problem between water and air, air enthalpy balance, moisture fraction balance, water enthalpy balance, and water mass balance equations are solved with Navier-Stoke`s equations simultaneously. For the effect of turbulence, the standard k-{epsilon} turbulent model is implied in this analysis. The predicted result of the present analysis is compared with the experimental data and the commercial software result to validate the present study. The predicted results show good agreement with the experimental data and the commercial software result. To investigate the influence of the cooling tower design parameters such as approach, range and wet bulb temperature, parametric studies are also performed. (author). 15 refs., 11 figs., 8 tabs.

  8. Cementitious stabilization of chromium, arsenic, and selenium in a cooling tower sludge

    International Nuclear Information System (INIS)

    The Federal Facility Compliance Agreement (FFCA) establishes an aggressive schedule for conducting studies and treatment method development under the treatability exclusion of RCRA for those mixed wastes for which treatment methods and capabilities have yet to be defined. One of these wastes is a radioactive cooling tower sludge. This paper presents some results of a treatability study of the stabilization of this cooling tower sludge in cementitious waste forms. The sample of the cooling tower sludge obtained for this study was found to be not characteristically hazardous in regard to arsenic, barium, chromium, lead, and selenium, despite the waste codes associated with this waste. However, the scope of this study included spiking three RCRA metals to two orders of magnitude above the initial concentration to test the limits of cementitious stabilization. Chromium and arsenic were spiked at concentrations of 200, 2,000, and 20,000 mg/kg, and selenium was spiked at 100, 1,000, and 10,000 mg/kg (concentrations based on the metal in the sludge solids). Portland cement, Class F fly ash, and slag were selected as stabilizing agents in the present study. Perlite, a fine, porous volcanic rock commonly used as a filter aid, was used as a water-sorptive agent in this study in order to control bleed water for high water contents. The highly porous perlite dust absorbs large amounts of water by capillary action and does not present the handling and processing problems exhibited by clays used for bleed water control

  9. The Worlds First Ever Cooling Tower Acceptance Test Using Process Data Reconciliation

    International Nuclear Information System (INIS)

    The cooling capacity of cooling towers is influenced by multiple constructive and atmospheric parameters in a very complex way. This leads to strong variations of the measured cold-water temperature and causes unacceptable unreliability of conventional acceptance tests, which are based on single point measurements. In order to overcome this lack of accuracy a new approach to acceptance test based on process data reconciliation has been developed by BTB Jansky and applied at a nuclear power plant. This approach uses process data reconciliation according to VDI 2048 to evaluate datasets over a long period covering different operating conditions of the cooling tower. Data reconciliation is a statistical method to determine the true process parameters with a statistical probability of 95% by considering closed material-, mass-and energy balances. Datasets which are not suitable for the evaluation due to strong transient gradients are excluded beforehand, according to well-defined criteria. The reconciled cold-water temperature is then compared, within a wet bulb temperature range of 5 deg. C to 20 deg. C to the manufacturer's guaranteed temperature. Finally, if the average deviation between reconciled and guaranteed value over the evaluated period is below zero, the cooling tower guarantee is fulfilled. (authors)

  10. Rainfall enhancement due to scavenging of cooling tower condensate

    International Nuclear Information System (INIS)

    Estimates of rainfall enhancement resulting from scavenging of cooling tower condensate droplets were made using relevant aerosol scavenging theory and a range of meteorological conditions. For a large natural-draft tower, releasing 1.7 x 105 g/sec of condensate, plume centerline rainfall enhancement is predicted to be measurably high at downwind distances between 100 m and 1 km for moderate wind speeds and rainfall rates. The cumulative removal of condensate by scavenging should be significant, even in a light rain (1 mm/hr), where removal half-distances are predicted to be 2.5, 10, and 20 km for wind speeds of 1, 5, and 10 m/sec, respectively

  11. Experience with the operation during winter of wet cooling towers with a varied concept of the main cooling system

    International Nuclear Information System (INIS)

    On the basis of experience gained from cooling towers in operation it is prudent to operate 'in advance' new cooling towers in accordance with the load and air temperature to be expected. Experience during winter operation, which influences the design of new installations, has been accumulated from the cooling towers at Philippsburg and Grohnde nuclear power stations and also from those at the district heating power plant of Volkswagen at Wolfsburg. The measures taken cannot and should not totally prevent ice formation; however, with future expected methods of operation of cooling towers it is possible to foresee uninterrupted operation during winter. (orig.)

  12. Thermal investigation of ETRR-2 research reactor with different induced draft wet cooling tower

    International Nuclear Information System (INIS)

    The thermal performance of nuclear reactor is directly affected by its cooling system. The cooling tower plays an important role in this cooling system to evacuate the heat generated in the nuclear reactor core. In this work simple mathematical model is used to compare a two cooling towers; the first cooling tower which operated in the reactor till 2003 and the second one (current) which replaced the first.in 2003, to predict a core inlet temperature and a cooling tower outlet temperature. The effect of ambient condition on the performance is measured. An Engineering Equation Solver program (EES) is used to simulate the integrated cooling system and the model is validated by readings from control room monitors in the reactor. The results showed better performance of the present cooling tower

  13. Noise radiation from natural-draft cooling towers for nuclear power plants

    International Nuclear Information System (INIS)

    A procedure for computing the noise levels in the vicinity of natural-draft cooling towers is presented. The noise levels are computed in overall and octave band levels with A-weighting and with no weighting. Attenuation of the noise by wave spreading, atmospheric absorption, barrier screening, vegetation, and wind and temperature gradients are included. The procedure is applied to a nuclear power plant served by four cooling towers and to a nuclear energy center with forty cooling towers

  14. the effect of design changes of cooling tower on the performance of ETRR-2 reactor

    International Nuclear Information System (INIS)

    the egyptian testing and research reactor(ETRR-2) were established in 1998 with maximum power 22 MW for research purposes. two induced draft cooling towers with different specifications was installed inh the system, a replaced (old) cooling tower was in operation from 1998 to 2003, and the present (new) cooling tower was in operation from 2003 till now. the reactor was put into operation since 1998 but it faced a lot of problems in the cooling system concerning with the thermal load dissipation. some efforts guided to study this problem to evaluate the old and present cooling tower to decide if the present cooling tower achieves a good performance in the reactor cooling system and to know why the old cooling tower have to be replaced ? and to avoid thermal problems in the future to satisfy the stable operation. in this work the study of the cooling system of the ETRR-2 is presented. this study is based on analytical, numerical and measurement investigations of the cooling system following three parts. he first part depicts the analytical solution of integrated cooling system of the reactor, the second part depicts the numerical solution of the cooling tower packing , and the third part is the evaluation of the cooling system using cooling technology, institute procedure (CTI)

  15. Reuse of refinery's tertiary-treated wastewater in cooling towers: microbiological monitoring.

    Science.gov (United States)

    Dos Santos, Vera Lúcia; Veiga, Andréa Azevedo; Mendonça, Rafael Silva; Alves, Andrea Lima; Pagnin, Sérgio; Santiago, Vânia M J

    2015-02-01

    The study was planned to quantify the distribution of bacteria between bulk water and biofilm formed on different materials in an industrial scale cooling tower system of an oil refinery operating with clarified and chlorinated freshwater (CCW) or chlorinated tertiary effluent (TRW) as makeup water. The sessile and planktonic heterotrophic bacteria and Pseudomonas aeruginosa densities were significantly higher in the cooling tower supplied with clarified and chlorinated freshwater (CTCW) (p?towers, the biofilm density was higher on the surface of glass slides and stainless steel coupons than on the surface of carbon steel coupons. The average corrosion rates of carbon steel coupons (0.4-0.8 millimeters per year (mpy)) and densities of sessile (12-1.47?×?10(3) colony-forming unit (CFU)?cm(-1)) and planktonic (0-2.36?×?10(3) CFU mL(-1)) microbiota remained below of the maximum values of reference used by water treatment companies as indicative of efficient microbial control. These data indicate that the strategies of the water treatment station (WTS) (free chlorine) and industrial wastewater treatment station (IWTS) followed by reverse electrodialysis system (RES) (free chlorine plus chloramine) were effective for the microbiological control of the two makeup water sources. PMID:25226836

  16. Studies of the environmental impact of evaporative cooling tower plumes

    International Nuclear Information System (INIS)

    This ongoing research program of the environmental impact of natural-draft evaporative cooling tower plumes consists principally of a comprehensive series of airborne measurements of a variety of the physical characteristics of the plumes and, to a lesser extent, of preliminary studies of remote sodar plume probing techniques and the development of simplified dynamical numerical models suitable for use in conducting field measurement programs. The PSU Doppler sodar was used at the Keystone Power Plant in southwestern Pennsylvania for an extended series of remote measurements of the characteristics of plume turbulent temperature and velocity fluctuations and results are discussed

  17. Heat rejection enhancement in natural draft cooling tower using radiator-type windbreakers

    International Nuclear Information System (INIS)

    Highlights: • Radiator-type windbreakers are more efficient than solid types. • They can improve cooling efficiency by three times of solid types. • Radiator-type windbreakers are efficient even at normal condition. - Abstract: Cooling efficiency of a natural draft dry cooling tower decreases under crosswind condition. Many researchers frequently recommended solid windbreakers to improve the cooling efficiency. The present research work concerns with the cooling performance assessment of the cooling tower under crosswind condition when the windbreakers are fabricated from the same type of cooling tower radiators. Computational fluid dynamics approach based on the finite volume method has been used to assess the cooling performance of the cooling tower. Numerical results show that radiator type windbreakers can substantially more improve the cooling efficiency than the usual solid types do

  18. Effects of inlet relative humidity and inlet temperature on the performance of counterflow wet cooling tower based on exergy analysis

    International Nuclear Information System (INIS)

    The purpose of this study is to analyze the influence of the ambient temperature and humidity on the performance of a counterflow wet cooling tower according to the second law, exergy analysis, of thermodynamics. First, the properties of water and air flow through the tower were predicted and validated by the experiment. Exergy analysis then has been carried out for investigating the cooling tower performance with various inlet air conditions, relative humidity and dry bulb temperature, while the water side condition is kept constant. According to the analysis in this paper, the similar result in terms of required dry air flow rate, exergy change of water and that of air, exergy destruction and second law efficiency were obtained for the various inlet air conditions. The exergy change of water ?xw is higher than that of air ?xair, since ?xw is the available energy of water to supply to air throughout the tower while ?xair is the available energy of air to recover or utilize that supplied by water. It reveals that ?xair is dominated by the exergy change of air due to evaporative heat transfer. In addition, it gives a clearer explanation of the cooling tower performance and gives clear trends for optimization

  19. Towards safe and economic seismic design of cooling towers of extreme height

    International Nuclear Information System (INIS)

    Nuclear power plants are being increasingly equipped with natural draught cooling towers of heights greater than 160 m. In many arid zones, where high natural draught cooling towers with dry cooling systems are being projected, wind loads are relativelly small while site seismicity is relatively high. Thus the ability of the tower to withstand earthquake induced forces governs its design. On the other hand, most reinforced concrete cooling towers of extreme height built so far were designed to withstand high wind loads and moderate earthquake loads. The effects of special structural measures for obtaining an economic design, such as the introduction of ring stiffened shells, have been studied mainly for those towers. In view of the previous aspects it is the purpose of this paper to analyze the effects of various structural measures and other parameters on the seismic response of such high cooling towers. (orig.)

  20. Optimization of mechanical draft counter flow wet-cooling tower using artificial bee colony algorithm

    International Nuclear Information System (INIS)

    Research highlights: ? ABC algorithm is used for optimization of counter flow wet-cooling tower. ? Minimizing the total annual cost for specific heat duty is the objective function. ? Six examples are presented to demonstrate the effectiveness of the proposed algorithm. ? The results are compared with the results of GAMS optimization package. ? The ABC algorithm can be modified to suit optimization of other thermal systems. -- Abstract: This study explores the use of artificial bee colony (ABC) algorithm for design optimization of mechanical draft counter flow wet-cooling tower. Minimizing the total annual cost for specific heat duty requirement is considered as objective function. Three design variables such as water to air mass ratio, mass velocity of water and mass velocity of air are considered for optimization. Evaluations of the cooling tower geometry and performances are based on an adaptive version of Merkel's method. Temperature and enthalpy constraints are included in the optimization procedure. Six examples are presented to demonstrate the effectiveness and accuracy of the proposed algorithm. The results of optimization using ABC are validated by comparing with those obtained by using GAMS optimization package. The effect of variation of ABC parameters on the convergence and optimum value of the objective function has also been presented.

  1. Optimization of mechanical draft counter flow wet-cooling tower using artificial bee colony algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Rao, R.V., E-mail: ravipudirao@gmail.co [S.V. National Institute of Technology, Surat, Gujarat State 395 007 (India); Patel, V.K. [S.V. National Institute of Technology, Surat, Gujarat State 395 007 (India)

    2011-07-15

    Research highlights: {yields} ABC algorithm is used for optimization of counter flow wet-cooling tower. {yields} Minimizing the total annual cost for specific heat duty is the objective function. {yields} Six examples are presented to demonstrate the effectiveness of the proposed algorithm. {yields} The results are compared with the results of GAMS optimization package. {yields} The ABC algorithm can be modified to suit optimization of other thermal systems. -- Abstract: This study explores the use of artificial bee colony (ABC) algorithm for design optimization of mechanical draft counter flow wet-cooling tower. Minimizing the total annual cost for specific heat duty requirement is considered as objective function. Three design variables such as water to air mass ratio, mass velocity of water and mass velocity of air are considered for optimization. Evaluations of the cooling tower geometry and performances are based on an adaptive version of Merkel's method. Temperature and enthalpy constraints are included in the optimization procedure. Six examples are presented to demonstrate the effectiveness and accuracy of the proposed algorithm. The results of optimization using ABC are validated by comparing with those obtained by using GAMS optimization package. The effect of variation of ABC parameters on the convergence and optimum value of the objective function has also been presented.

  2. Emission of asbestos fibres from natural-draught cooling towers. Pt. 1 and 2

    International Nuclear Information System (INIS)

    Sampling for the studies reported has been done in a relatively new nuclear power plant with natural-draught, wet cooling tower, and in an older, brown-coal fired power plant with the same type of cooling towers, both towers equipped with internal structures made of asbestos cement. Samples have been taken from the plumes, air in the environment, cooling water receiving tank, make-up water. The samples have been primarily examined for their content of asbestos fibres. The results show that relatively few asbestos is found in the environmental air and in the cooling water receiving tank. Putting it continuously, it can be said that the cooling water entrains only little amounts of the asbestos of the internal structures. The plume samples indicate emission of some thousand asbestos fibres per m3, or less than 1 ng. Taking into account one sample exhibiting an extremely high amount of asbestos, the average emission of asbestos fibres with the plumes is 106 fibres per m3, or 100 ng/m3 of plume. The maximum air pollution thus calculated in accordance with TA Luft (Clean Air Technical Directive), for the less favourable weather conditions at a hight of 2 m above ground, is 10 fibres per one m3 of air; including the extreme data of the single sample mentioned above, the result is some thousand fibres per m3. The data are far below the TRK data (Technical guiding data for maximum concentration at the place of work), which state a maximum of 106 fibres per m3. (orig.)

  3. Study plan for conducting a section 316(a) demonstration: K-Reactor cooling tower, Savannah River Site

    International Nuclear Information System (INIS)

    The K Reactor at the Savannah River Site (SRS) began operation in 1954. The K-Reactor pumped secondary cooling water from the Savannah River and discharged directly to the Indian Grave Branch, a tributary of Pen Branch which flows to the Savannah River. During earlier operations, the temperature and discharge rates of cooling water from the K-reactor were up to approximately 70 degree C and 400 cfs, substantially altering the thermal and flow regimes of this stream. These discharges resulted in adverse impacts to the receiving stream and wetlands along the receiving stream. As a component of a Consent Order (84-4-W as amended) with the South Carolina Department of Health and Environmental Control, the Department of Energy (DOE) evaluated the alternatives for cooling thermal effluents from K Reactor and concluded that a natural draft recirculating cooling tower should be constructed. The cooling tower will mitigate thermal and flow factors that resulted in the previous impacts to the Indian Grave/Pen Branch ecosystem. The purpose of the proposed biological monitoring program is to provide information that will support a Section 316(a) Demonstration for Indian Grave Branch and Pen Branch when K-Reactor is operated with the recirculating cooling tower. The data will be used to determine that Indian Grave Branch and Pen Branch support Balanced Indigenous Communities when K-Reactor is operated with a recirculating cooling tower. 4 refs., 1 fig. 1 tab

  4. Design of a water tower in concrete

    OpenAIRE

    Tsiakouris, Marios

    1995-01-01

    The water tower will be designed using the British standard BS 811 (Structural use of concrete) and BS 8007 (Design of concrete structuresfor( retaining aqueous liquids).The design should be carried out using limit state design. The application of limit state design by BS 8110 is subjected to modifications contained in BS 8007. The limit state design is based on both ultimate and serviceability limit state.

  5. A computer code for particular operating conditions of wet cooling towers

    International Nuclear Information System (INIS)

    In most cases, normal operation of wet cooling towers can be described with a one dimensional model because the flows are practically uniform. Nevertheless, more accurate calculations are sometimes requested. Packing thickness is not always constant. And the antifreeze system which consist in putting the whole water flow on one part only of the packing or in closing a part of the air inlet leads to non-uniform operating conditions. ETHER computer code was developed for the studies of non-uniform operating conditions of counter-flow natural draft wet cooling towers. ETHER is a bidimensional axisymetric code which solves Navier-Stokes equations with a method of finite differences for the air flow in a region limited by the inlet and the outlet of the tower. Water, flow, packing thickness, cold rain height and inlet air velocity are given in every mesh. The only experimental correlations needed are those of heat and mass transfer and those of head loss in the packing. With a time of computation from 20 s to 400 s, the code provides air velocities, pressures and the profile of cold water temperature

  6. Prevalence and Molecular Characteristics of Waterborne Pathogen Legionella in Industrial Cooling Tower Environments

    Directory of Open Access Journals (Sweden)

    Lijie Li

    2015-10-01

    Full Text Available Cooling towers are a source of Legionnaires’ disease. It is important from a public health perspective to survey industrial cooling towers for the presence of Legionella. Prospective surveillance of the extent of Legionella pollution was conducted at factories in Shijiazhuang, China between March 2011 and September 2012. Overall, 35.7% of 255 industrial cooling tower water samples showed Legionella-positive, and their concentrations ranged from 100 Colony-Forming Units (CFU/liter to 88,000 CFU/liter, with an average concentration of 9100 CFU/liter. A total of 121 isolates were obtained. All isolates were L. pneumophila, and the isolated serogroups included serogroups 1 (68 isolates, 56.2%, 6 (25, 20.7%, 5 (12, 9.9%, 8 (8, 6.6%, 3 (6, 5.0% and 9 (2, 1.6%. All 121 isolates were analyzed by pulsed-field gel electrophoresis (PFGE and 64 different patterns were obtained. All 121 isolates were analyzed sequence-based typing (SBT, a full 7-allele profile was obtained from 117 isolates. One hundred and seventeen isolates were divided into 49 sequence types. Two virulence genes, lvh and rtxA, are analyzed by polymerase chain reaction (PCR. 92.6% (112/121 and 98.3% (119/121 isolates carried lvh and rtxA respectively and 90.9% (110/121 of tested isolates carried both genes. Our results demonstrated high prevalence and genetic polymorphism of L. pneumophila in industrial cooling tower environments in Shijiazhang, China, and the SBT and virulence gene PCR results suggested that the isolates were pathogenic. Improved control and prevention strategies are urgently needed.

  7. Wind effects on optimal aerodynamic conditions for a wet cooling tower with natural draft

    International Nuclear Information System (INIS)

    Among the problems of an aerodynamic nature, related to the wind action, the two following ones have to be studied through model tests to reach a better knowledge of design and operating conditions of counterflow natural draft wet cooling towers with water recovery systems. - Wind effects on performance. A very general phenomenon. In order to minimize this alteration, a common idea is to install radio windbrake walls. - Wind effects on the forces applied to the internal structures and thermal components. A relatively elaborate model, representative of a lower plenum layout was fitted with a sufficiently large number of pressure tapes to draw up the distribution of the pressure acting upon: - the packing, - the water recovery system, - the windbrake walls (eventually) and for various combination of these elements. The air flow mode in the tower was also observed. All these observations were made with different wind directions. This study showed that the forces were very variable geographically, very sensitive to the layout

  8. Wind effects on optimal aerodynamic conditions for a wet cooling tower with natural draft

    Energy Technology Data Exchange (ETDEWEB)

    Blanquet, J.C.; Goldwirt, F.; Manas, B.

    1988-04-01

    Among the problems of an aerodynamic nature, related to the wind action, the two following ones have to be studied through model tests to reach a better knowledge of design and operating conditions of counterflow natural draft wet cooling towers with water recovery systems. - Wind effects on performance. A very general phenomenon. In order to minimize this alteration, a common idea is to install radio windbrake walls. - Wind effects on the forces applied to the internal structures and thermal components. A relatively elaborate model, representative of a lower plenum layout was fitted with a sufficiently large number of pressure tapes to draw up the distribution of the pressure acting upon: - the packing, - the water recovery system, - the windbrake walls (eventually) and for various combination of these elements. The air flow mode in the tower was also observed. All these observations were made with different wind directions. This study showed that the forces were very variable geographically, very sensitive to the layout.

  9. Solving the heat transfer in the cold rain of a cross flow cooling tower. N3S code - cooling tower release

    International Nuclear Information System (INIS)

    A simplified model for heat and mass transfer in the lower rainfall of a counter-flow cooling toward had to be implemented in the N3S code-cooling tower release It is built from an old code: ZOPLU. The air velocity field is calculated by N3S. The air and water temperature fields are solved by a Runge-Kutta method on a mesh in an adequate number of vertical plans. Heat exchange and drags correlations are given. And all the necessary parameters are specified. All the subroutines are described. They are taken from ZOPLU and modified in order to adapt their abilities to the N3S requirements. (author). 6 refs., 3 figs., 3 tabs., 3 appends

  10. Thermodynamic study of the effects of ambient air conditions on the thermal performance characteristics of a closed wet cooling tower

    International Nuclear Information System (INIS)

    A thermodynamic model was developed and used to assess the sensitivity of thermal performance characteristics of a closed wet cooling tower to inlet air conditions. In the present study, three cases of different ambient conditions are considered: In the first case, the average mid-winter and mid-summer conditions as well as the extreme case of high temperature and relative humidity, in Athens (Greece) during summer are considered according to the Greek Regulation for Buildings Energy Performance. In the second case, the varied inlet air relative humidity while the inlet air dry bulb temperature remains constant were taken into account. In the last case, the effects on cooling tower thermal behaviour when the inlet air wet bulb temperature remains constant were examined. The proposed model is capable of predicting the variation of air thermodynamic properties, sprayed water and serpentine water temperature inside the closed wet cooling tower along its height. The reliability of simulations was tested against experimental data, which were obtained from literature. Thus, the proposed model could be used for the design of industrial and domestic applications of conventional air-conditioning systems as well as for sorption cooling systems with solid and liquid desiccants where closed wet cooling towers are used for precooling the liquid solutions. The most important result of this theoretical investigation is that the highest fall of serpentine water temperature and losses of sprayed water are observed for the lowest value of inlet wet bulb temperature. Hence, the thermal effectiveness, which is associated with the temperature reduction of serpentine water as well as the operational cost, which is related to the sprayed water loss due to evaporation, of a closed wet cooling tower depend predominantly on the degree of saturation of inlet air.

  11. Reuso de efluentes em torres de resfriamento - estudo conceitual: Aeroporto Internacional do Rio de Janeiro = Water reuse for cooling towers – conceptual study: Rio de Janeiro International Airport

    Directory of Open Access Journals (Sweden)

    Denize Dias de Carvalho

    2010-07-01

    Full Text Available O reuso de água é ferramenta valiosa na gestão da água, que promove a otimização da utilização do recurso desta, que reduz e, muitas vezes, até elimina os impactos no meio ambiente. Neste trabalho foi investigada a composição do efluente secundário da estação de tratamento de efluentes (ETE APOIO do Aeroporto Internacional do Rio de Janeiro, com o objetivo de propor o processo adequado à reutilização deste efluente como água de reposição nas torres de resfriamento desse Aeroporto. Com base nas análises de cátions, ânions, DBO e DQO, verificou-se o parâmetro SDT - Cl- como crítico para processamento do efluente. Foi proposta uma sequência para reutilização do efluente que continha o tratamento de osmose inversa, o custo do m3 produzido por essa sequência foi estimado em R$ 2,90 m-3. Water reuse is an important tool in water management; it is a conceptthat promotes optimization of the water resource, reducing and often even eliminating environmental impacts. In this work, the composition of a secondary effluent (from the effluent treatment station (ETE APOIO at Rio de Janeiro International Airport was analyzed, with theaim of determining an adequate process for the reutilization of this effluent as replacement cooling water. Chemical analyses such as cation and anion analysis, BOD and COD were performed. Based on these analyses, it was found that TDS - Cl- was the critical parameter foreffluent processing. A treatment system was proposed for effluent reuse including reverse osmosis; the cost estimate per m3 produced by this system was R$ 2.90 m-3.

  12. Thermal performance analysis of heat exchanger for closed wet cooling tower using heat and mass transfer analogy

    International Nuclear Information System (INIS)

    In closed wet cooling towers, the heat transfer between the air and external tube surfaces can be composed of the sensible heat transfer and the latent heat transfer. The heat transfer coefficient can be obtained from the equation for external heat transfer of tube banks. According to experimental data, the mass transfer coefficient was affected by the air velocity and spray water flow rate. This study provides the correlation equation for mass transfer coefficient based on the analogy of the heat and mass transfer and the experimental data. The results from this correlation equation showed fairly good agreement with experimental data. The cooling capacity and thermal efficiency of the closed wet cooling tower were calculated from the correlation equation to analyze the performance of heat exchanger for the tower

  13. Deposition and corrosion phenomena on aluminum surfaces under deluged dry cooling-tower condisions. Interim report

    Energy Technology Data Exchange (ETDEWEB)

    Wheeler, K.R.; May, R.P.; Douglas, J.G.; Tylczak, J.H.

    1981-07-01

    Deposition and corrosion on aluminum heat exchanger surfaces resulting from deluge in wet/dry cooling towers is simulated in a laboratory Corrosion/Deposition Loop (CDL). Heat exchanger deposition buildup was found to be linearly dependent on concentration factor and number of wet/dry cycles. Deionized water rising after deluge reduced rate of deposition. Laboratory data obtained from CDL relates directly to operation of the Advanced Concepts Test (ACT) demonstration cooling tower. Technology transferable to ACT shows that deposition from supersaturated solution can be effectively controlled by attention to water chemistry, pH, water conditioning, and good heat transfer design. The additional mechanism of deposition by water film evaporation is effectively managed by soft water rinsing and uniform surface wetting. Exposure of a model TRANE surface (the ACT wet/dry exchanger) produced short-term deposition extrapolating to 0.011 mm buildup in three years. Studies continue to verify 4X as maximum cycles of concentration through control of water chemistry and rinsing after deluge. Deluge water used at ACT facility is sufficiently aggressive to warrant use of Alclad to extend tube service life.

  14. Analysis Of Cooling Tower Performance From Safety Factor Of Kartini Reactor Operation

    International Nuclear Information System (INIS)

    Analysis of cooling tower performance from power generation of Kartini reactor has been done. The data's was observed with cooling tower coupled by plate and cylinder type heat exchanger. The Kartini reactor operated with nominal power at 100 k W during 24 hours and environmental data's observation have been done in ever 2 hours, Analysis and calculation used by Number of diffusion Unit and Enthalpy Balance Method to find NDU parameter. The NDU parameter is value heat transfer processing in cooling tower system. The NDU parameter used to find of safety factor and maintenance schedule of cooling tower. From analysis and calculation resulted value of NDU operation under of NDU design and performance of cooling tower is safe

  15. Girassol, Riser Towers for ultra deep water

    Energy Technology Data Exchange (ETDEWEB)

    Rougier, Regis

    1999-07-01

    This is a brief presentation of the technical concept developed by ALTO MAR GIRASSOL (AMG) for the Girassol umbilical and flowlines system. In 1998 AMG was awarded a contract by Elf Exploration Angola for the engineering, procurement, construction and installation (EPCI) of the umbilical and flowline system. The technical concept is based around the use of sealine bundles and self-supporting hybrid riser towers which carry the production, water injection, gas injection, gas lift and service lines. The items discussed are: (1) selected field layout, (2) seabed flowlines, hybrid riser system, umbilicals, export lines, installation plan and overall project schedule.

  16. Building concept of cooling towers for WWER-1000 nuclear power plants

    International Nuclear Information System (INIS)

    A project is described of cooling towers with natural draught for the Temelin nuclear power plant. The concept proceeds from the classical design of the so-called Itterson type, i.e., the outer cladding of the draught stack is made of a monolithic reinforced concrete unit in the shape of a hyperboloid of revolution supported by a system of oblique supports mounted along the edge of the cooled water tank. The procedure is explained of the thermal calculation for the given operating conditions. The basic alternatives are considered of the choice of material and design of the cooling system. Questions are discussed relating to the design of the eliminator, the windwart wall and the shape of the shell of the draught stack and its loading by wind and seismic effects. (E.S.)

  17. Exergy transfer and parametric study of counter flow wet cooling towers

    International Nuclear Information System (INIS)

    A thermodynamic analysis of the counter flow wet cooling tower (CWCT) is performed in this paper. Both energy and exergy formulations are developed and validated for the system. Four types of exergy transfer processes occurring inside the CWCT are investigated schematically. A parametric study is conducted under various operating conditions in order to investigate the effects of thermal efficiency and water-to-air ratio on the exergy performance of the CWCT. Unlike past studies, the transiting exergy contained in the inlet and outlet water is not considered. It is found that the exergy efficiency is always less than 25%. The exergy parameters including evaporation water loss, exergy efficiency, exergy input, internal and external exergy losses are very sensitive to the thermal efficiency when it is very close to 1.0 at lower water-to-air ratios. - Research highlights: ? We model counter flow wet cooling towers and make a detailed exergy analysis. ? Four types of exergy transfer processes are investigated schematically. ? Only a small part of exergy input, less than 25%, is effectively utilized.

  18. Concept of CFD model of natural draft wet-cooling tower flow

    OpenAIRE

    Hyhlík T.

    2014-01-01

    The article deals with the development of CFD model of natural draft wet-cooling tower flow. The physical phenomena taking place within a natural draft wet cooling tower are described by the system of conservation law equations along with additional equations. The heat and mass transfer in the counterflow wet-cooling tower fill are described by model [1] which is based on the system of ordinary differential equations. Utilization of model [1] of the fill allows us to apply commonly measured f...

  19. Radiometric modeling of mechanical draft cooling towers to assist in the extraction of their absolute temperature from remote thermal imagery

    Science.gov (United States)

    Montanaro, Matthew; Salvaggio, Carl; Brown, Scott D.; Messinger, David W.; Garrett, Alfred J.; Bollinger, James S.

    2009-05-01

    Determining the internal temperature of a mechanical draft cooling tower (MDCT) from remotely-sensed thermal imagery is important for many applications that provide input to energy-related process models. The problem of determining the temperature of a MDCT is unique due to the geometry of the tower and due to the exhausted water vapor plume. The radiance leaving the tower is dependent on the optical and thermal properties of the tower materials (i.e., emissivity, BRDF, temperature, etc.) and also the internal geometry of the tower. The tower radiance is then propagated through the exhaust plume and through the atmosphere to arrive at the sensor. The expelled effluent from the tower consists of a warm plume with a higher water vapor concentration than the ambient atmosphere. Given that a thermal image has been atmospherically compensated, the remaining sources of error in extracted tower temperature due to the exhausted plume and the tower geometry must be accounted for. A temperature correction factor due to these error sources will be derived through the use of three-dimensional radiometric modeling. A range of values for each important parameter are modeled to create a target space (i.e., look-up table) that predicts the internal MDCT temperature for every combination of parameter values. This LUT, along with user knowledge of the scene, provides a means to convert the imagederived apparent temperature into the estimated absolute temperature of a MDCT. Preliminary results indicate that temperature error corrections of approximately 1 - 9 Kelvin can be achieved with the range of MDCT parameters encompassed by the LUT.

  20. Maintenance of cooling towers following two outbreaks of Legionnaires' disease in a city.

    OpenAIRE

    Bhopal, R.S.; Barr, G.

    1990-01-01

    This survey assessed the maintenance of evaporative cooling towers in Glasgow, following two Legionnaires' disease outbreaks. Information was obtained from 76 of 81 premises and a maintenance score was calculated for each of 174 towers. The quality of maintenance was extremely varied (range of maintenance scores, 8-30; mean, 22 (S.D., 5.0); median, 23; maximum possible, 33) and some towers were neglected. Breaches of maintenance principles were mainly structural and organizational, e.g. inade...

  1. Cooling tower for the throughput of atmospheric cooling air for thermal power plants and other plants

    International Nuclear Information System (INIS)

    The special configuration of the heat exchanger of this dry-type cooling tower is to bring about an improvement of the specific cooling capacity, i.e. a reduction of the overall light and/or a saving of the capacity necessary for a permanent draught increase. This is achieved by enlarging the distance between tubes presenting the numerous tube bundles which form the heat exchanger, because the flow resistance for cooling air is drastically reduced. Although the tube bundles - the number of tubes per tube bundle being nearly the same - require more depth in the direction of the air-flow, the overall effect will be achieved in the sense of the task to be fulfilled. (HP)

  2. Structural inspection and wind analysis of redwood cooling towers at the Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    As part of the plant upgrade program, structural analyses and field inspections were performed on four redwood cooling towers at the DOE Portsmouth gaseous diffusion plant located in Piketon, Ohio. The cooling towers are categorized as important hazard facilities. The loadings are derived from UCRL-15910 according to the pertinent hazard category. In addition to the seismic and wind loadings, the wood cooling towers are constantly subject to adverse environmental effects such as elevated temperature, chemical attack, icing and snow load, and motor vibrations. A thorough structural evaluation for all load combinations was performed for each of the cooling towers based on the structural code requirements of the Cooling Tower Institute and National Forest Products Association. Most stress criteria are unique for the redwood material. This evaluation was performed using finite element techniques on the global structural integrity and supplemented by hand calculations on the individual connection joints. Overloaded wood structural members and joints are identified by the analysis. The rectangular tower structure sits on a concrete basin that span across 60 ft by 200 ft. A major part of the cooling towers upgrading program involved field inspections of the individual cells of each tower. The primary purpose of these inspections was to identify any existing structural damage or deficiencies such as failed members, degraded wood, and deficiencies resulting from poor construction practice. Inspection of 40 cells identified some generic deficiencies that mostly are consistent with the analytical finding. Based on the analysis, some effective but inexpensive upgrading techniques were developed and recommended to bring the cooling towers into compliance with current DOE requirements

  3. The dynamics of natural-draft cooling towers under seismic excitation

    International Nuclear Information System (INIS)

    In the present paper a calculation model is presented permitting to evaluate the intersection and deformation parameters, occuring on the cooling towers due to seismic excitation, by means of the method of response spectra. (RW)

  4. Cooling towers: denvironmental studies (citations from the engineering index data base). Report for 1970-August 1978

    International Nuclear Information System (INIS)

    Abstracts from worldwide research on thermal, meteorological, and ecological effects associated with cooling towers used primarily by fossil fuel and nuclear power plants are cited. Citations cover plume behavior studies, including measurement of airborne particulate concentration, and characterization and management of drift as well as noise pollution and salt deposition effects on vegetation. A few abstracts pertain to environmental effects from cooling towers used in wastewater treatment

  5. Experimental study of the influence of atmospheric conditions on the performance of natural draft dry cooling towers

    International Nuclear Information System (INIS)

    The heat dissipation of cooling towers is influenced by atmospheric conditions. In order to establish these influences EIR conducted measurements on a natural draft dry cooling tower. During two measuring campaigns with a duration of total 10 weeks the performance of the cooling tower, the ambient air temperatures, the wind velocities and directions as well as air temperature at the top of the tower and in front of the heat exchangers were continuously measured and registered. The results achieved enable the quantitative description of the influence of the ambient air temperature, wind and temperature inversion on the performance of natural draft dry cooling towers. (Auth.)

  6. Transmission of waste heat to the environment - cooling with river-water and in circulating systems

    International Nuclear Information System (INIS)

    There is at present in the Federal Republic a revolution in the application of cooling methods, due to the present water economy situation for cooling water supply. Until the end of the 60's fresh-water cooling governed; today, wet closed-circuit cooling in cooling towers is coming through. Furthermore, the application of dry cooling required for the future is being prepared. A survey of the cooling methods, the related problems and the economic effects is given. (orig.)

  7. Optimization of water-cooled chiller system with load-based speed control

    International Nuclear Information System (INIS)

    This study investigates the energy performance of chiller and cooling tower systems integrated with variable condenser water flow and optimal speed control for tower fans and condenser water pumps. Thermodynamic-behaviour chiller and cooling tower models were developed to assess how different control methods of cooling towers and condenser water pumps influence the trade-off between the chiller power, pump power, fan power and water consumption under various operating conditions. Load-based speed control is introduced for the tower fans and condenser water pumps to achieve optimum system performance. With regard to an example chiller system serving an office building, the optimal control coupled with variable condenser water flow could reduce the annual system electricity use by 5.3% and operating cost by 4.9% relative to the equivalent system using constant speed fans and pumps with a fixed set point for cooling water temperature control

  8. Climatic uncertainty in Himalayan water towers

    Science.gov (United States)

    Mishra, Vimal

    2015-04-01

    The Himalayan water towers (e.g., Indus, Ganges, and Brahmaputra) play a major role in water resource availability and affect a significant population in the South Asia region. Climatic uncertainty in the region not only hampers progress toward process understanding but also decision making. Observational data sets show uncertainty (standard deviation in mean temperature in data sets) of 0.2 to 0.5°C in winter (January-February-March-April) and the monsoon season (June-July-August-September) air temperature. Observational uncertainty in precipitation in the winter and monsoon seasons ranged between 6 and 17% (with respect to ensemble mean seasonal precipitation) in the Indus, Ganges, and Brahmaputra river basins. The Coordinated Regional Climate Downscaling Experiment (CORDEX) South Asia regional climate models (CORDEX-RCMs) show larger uncertainty (1-3.6°C in temperature and 18-60% in precipitation) than that of the observations. Moreover, RCMs exhibit a large cold bias (6-8°C) and are not able to reproduce the observed warming in the Himalayan water towers. In fact, the CORDEX-RCMs overestimate observed warming by threefold in Ganges and Brahmaputra basins, which raises a question on their reliability on future warming trends in the region. The CORDEX-RCMs overestimate the area that experienced significant warming and fail to reproduce precipitation trends in both magnitude as well as direction. In observational data sets, uncertainty in precipitation and air temperature increases with elevation, which may be associated with sparse observations. However, the CORDEX-RCMs showed larger uncertainty at the lower elevations in both precipitation as well as temperature. The host general circulation models show a better performance in simulating winter climate than the CORDEX-RCMs, which suggest that an improved representation of elevation may not necessarily improve the model's performance. While observations show significant warming in the Indus basin and decline in the monsoon season precipitation in the Ganges basin, reliability of future climate projections and their impacts on water resources in the region will depend on improvements in the models and observations in coming years.

  9. Methodology for evaluation of cooling tower performance - Part 1: Description of the methodology

    International Nuclear Information System (INIS)

    Highlights: ? New methodology for evaluation of CT performance is presented. ? It enables to study impacts of local irregularities in CT on plant's power output. ? Poppe model for applications on the local basis of CTs is presented. ? Empirical model connecting cooling water temperature with power output is derived. ? Study is based on measured data from a plant and natural draft CT. - Abstract: A methodology for the evaluation of a natural draft cooling tower (CT) that is a part of a power plant is proposed. In this work the connection between CT performance and power output is established. The methodology consists of three subparts, i.e. Cooling Tower Profiler (CTP) method, CT model and model of a power plant. In the first part of the paper the three subparts of the methodology are described. Focus is given to the empirical model of the plant and a new application of the Poppe model. The simple empirical model enables accurate prediction of the power increase as a function of cooling water temperature and load to the plant. On the other hand, Poppe governing equations were derived for application on the local basis of CT. Moreover, the constraints and assumptions of CT analysis are discussed. The methodology is presented on real data from the power plant and CT. This is the base for application of the methodology presented in the second part of the paper where the focus is given on minimizing the error of the methodology. A small area with irregularities is analyzed and results are reported. Furthermore, a simplified computational approach to solving the Poppe equations is proposed yielding faster calculation with preserved accuracy.

  10. Methodology for evaluation of cooling tower performance - Part 1: Description of the methodology

    Energy Technology Data Exchange (ETDEWEB)

    Smrekar, J., E-mail: jure.smrekar@uis.no [Department of Mechanical and Structural Engineering and Materials Science, University of Stavanger, 4036 Stavanger (Norway); Kustrin, I.; Oman, J. [Department of Power Engineering, University of Ljubljana, Askerceva 6, SI-1000 Ljubljana (Slovenia)

    2011-10-15

    Highlights: {yields} New methodology for evaluation of CT performance is presented. {yields} It enables to study impacts of local irregularities in CT on plant's power output. {yields} Poppe model for applications on the local basis of CTs is presented. {yields} Empirical model connecting cooling water temperature with power output is derived. {yields} Study is based on measured data from a plant and natural draft CT. - Abstract: A methodology for the evaluation of a natural draft cooling tower (CT) that is a part of a power plant is proposed. In this work the connection between CT performance and power output is established. The methodology consists of three subparts, i.e. Cooling Tower Profiler (CTP) method, CT model and model of a power plant. In the first part of the paper the three subparts of the methodology are described. Focus is given to the empirical model of the plant and a new application of the Poppe model. The simple empirical model enables accurate prediction of the power increase as a function of cooling water temperature and load to the plant. On the other hand, Poppe governing equations were derived for application on the local basis of CT. Moreover, the constraints and assumptions of CT analysis are discussed. The methodology is presented on real data from the power plant and CT. This is the base for application of the methodology presented in the second part of the paper where the focus is given on minimizing the error of the methodology. A small area with irregularities is analyzed and results are reported. Furthermore, a simplified computational approach to solving the Poppe equations is proposed yielding faster calculation with preserved accuracy.

  11. 4. Meeting on cooling towers. From practice - for practice; 4. Kuehlturm-Tagung. Aus der Praxis - Fuer die Praxis

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-09-01

    The 4th Cooling Tower meeting brought into focus aspects of economic efficiency of the water cooling system, i.e. the papers analyse investment cost and operating cost taking into account environmental policy and interests. Numerous examples from practice are discussed in the papers showing how wet cooling tower design and application-specific selection of design features can influence the performance of the entire system. (orig./CB) [Deutsch] Im Mittelpunkt der 4. Kuehlturm-Tagung steht die Wirtschaftlichkeit der Wasserrueckkuehlanlage, d.h. die Betrachtung der Investitions- und Betriebskosten unter Beruecksichtigung der Belange des Umweltschutzes. Mit Beispielen aus der Praxis zeigen die Referenten, wie sich die Auslegung und Auswahl eines Nasskuehlturms auf das Betriebsergebnis der Anlage auswirken. (orig./GL)

  12. Conversion of water towers – an instrument for conserving heritage assets

    Directory of Open Access Journals (Sweden)

    Andreea-Loreta Cercleux

    2014-06-01

    Full Text Available Water towers are symbolical landmarks that refer to the industrialization. The oldest water towers are technical and industrial assets whose current and future evolution is a sensitive matter as a result of the economic context that brought about the closing of numerous industrial enterprises and abandoning infrastructure assets, including water towers. Some water towers were included on the national cultural-heritage lists across the world, thanks to the manifold values they incorporate (technological, historical, architectural, esthetical, among others. In this context, it has become necessary to convert them, with the twofold purpose of conserving them and assigning them a new function, for the local community members. Although there are numerous models for good practice in the conversion of water towers in several European countries, in Romania their reuse is a difficult process, most of the time burdened by shortcomings of legislation or lack of financial support. The study’s main purpose is to present reasons for the conversion of water towers and to highlight several good practice models, as well as to present several water towers with a high potential for conversion.

  13. Reinforced concrete column- supported by hyperboloid cooling tower stability assessment for seismic loads

    International Nuclear Information System (INIS)

    In recent years, the use of larger reinforced concrete column-supported hyperboloid cooling towers has been increased significantly. Thus, the investigation on failure criteria for structural components of such structures under different loads has been found as an essential need. Construction of cooling towers in seismic zones initiated the study on the dynamic behavior of such structures due to seismic loads. In this paper, finite element analyses have been performed to obtain the stress concentration, nonlinear behavior, stability or safety factor of the R. C. tower due to earthquakes loads. Outcomes of the study show that considerable plastic hinges were created in the X shape long columns of the R.C. hyperboloid cooling tower due to seismic loads, which resulted in a significant decrease in the stability safety factor and, an increase in concerns

  14. Dynamics of Legionella spp. and Bacterial Populations during the Proliferation of L. pneumophila in a Cooling Tower Facility?

    OpenAIRE

    Wéry, Nathalie; Bru-Adan, Valérie; Minervini, Céline; Delgénes, Jean-Philippe; Garrelly, Laurent; Godon, Jean-Jacques

    2008-01-01

    The dynamics of Legionella spp. and of dominant bacteria were investigated in water from a cooling tower plant over a 9-month period which included several weeks when Legionella pneumophila proliferated. The structural diversity of both the bacteria and the Legionella spp. was monitored by a fingerprint technique, single-strand conformation polymorphism, and Legionella spp. and L. pneumophila were quantified by real-time quantitative PCR. The structure of the bacterial community did not chang...

  15. Operation practice and implications of circulating cooling water system of American nuclear power plants

    International Nuclear Information System (INIS)

    In this paper, the circulating cooling water system of nuclear power plants (NPP) in United States is summarized, and the operation practices of different cooling water systems, such as once-through, natural and mechanical draft cooling tower, cooling pond, and mixed cooling mode, used by several coastal and inland NPPs are given. Also, based on the related experiences, some suggestions for use of cooling water system in China NPPs are presented. (authors)

  16. On cooling-water systems design for South African industry: Two recent developments

    Scientific Electronic Library Online (English)

    Thokozani, Majozi; Nongezile, Nyathi.

    2007-06-01

    Full Text Available This paper presents two recent developments in the targeting and design of cooling-water systems using process integration. The basis of this work is the observation that true optimization of any cooling-water system, comprising a cooling tower and a network of operations that use cooling water, can [...] be realized only by considering the system as a whole. Traditional approaches have focused separately on either the cooling tower or the operational network. Optimality, in the context of this paper, refers to minimum cooling-water flowrate to the network or maximum return temperature to the source of the cooling water (a cooling tower). Only systems with at least two cooling towers instead a single one are considered here, to highlight the complexity of a typical cooling-water system. The first exercise is based on a graphical technique in which targeting for the minimum cooling water precedes design of the cooling-water network to achieve the target. The second exercise uses mathematical modelling to optimize a superstructure that entails all possible topological arrangements of the cooling-water network. An industrial case study involving a South African explosives manufacturing plant is used to demonstrate the effectiveness of both techniques. Cooling-water savings of more than 20% were realized with modest capital investment.

  17. Nonlinear analysis of safety, damage and lifespan of wind-loaded natural draft cooling towers

    International Nuclear Information System (INIS)

    While being important and optically impressive components of thermal power plants, natural draught cooling towers are in effect comparatively thin shell structures that must withstand hurricane force winds. As past experience has proven, current German design and analysis concepts implicitly lead to safe structures, but due to their linear-elastic background they cannot supply answers to questions dealing with realistic collapse loads, failure mechanisms and estimations of life expectancies. In this paper, appropriate computer-based nonlinear analysis concepts are presented which deal with those aspects. After a short exposition of the theoretical background for modeling tower shells as multi-layered shell continua by mixed finite elements under consideration of shear deformations, the approach is demonstrated through numerical simulation of collapse loads and failure modes of the Gundremmingen cooling towers. Based on the methodology presented, appraisals of reduced life times for hurricane-damaged towers, as well as different repair and retrofitting strategies can be carried out. (orig.)

  18. Concept of CFD model of natural draft wet-cooling tower flow

    Directory of Open Access Journals (Sweden)

    Hyhlík T.

    2014-03-01

    Full Text Available The article deals with the development of CFD model of natural draft wet-cooling tower flow. The physical phenomena taking place within a natural draft wet cooling tower are described by the system of conservation law equations along with additional equations. The heat and mass transfer in the counterflow wet-cooling tower fill are described by model [1] which is based on the system of ordinary differential equations. Utilization of model [1] of the fill allows us to apply commonly measured fill characteristics as shown by [2].The boundary value problem resulting from the fill model is solved separately. The system of conservation law equations is interlinked with the system of ordinary differential equations describing the phenomena occurring in the counterflow wet-cooling tower fill via heat and mass sources and via boundary conditions. The concept of numerical solution is presented for the quasi one dimensional model of natural draft wet-cooling tower flow. The simulation results are shown.

  19. Updating of a finite element model of the Cruas 2 cooling tower

    International Nuclear Information System (INIS)

    A method based on modal analysis and inversion of a dynamic FEM model is used to detect changes in the dynamic behavior of nuclear plant cooling towers. Prior to detection, it is necessary to build a representative model of the structure. In this paper are given details about the CRUAS N. 2 cooling tower modelling and the updating procedure used to match the model to on-site measurements. First, were reviewed previous numerical and experimental studies on cooling towers vibrations. We found that the first eigenfrequencies of cooling towers are very sensitive to boundary conditions at the top and the bottom of the structure. Then, we built a beam and plate FEM model of the CRUAS N. 2 cooling tower. The first calculated modes were located in the proper frequency band (0.9 Hz - 1.30 Hz) but not distributed according to the experimental order. We decided to update the numerical model with MADMACS, an updating model software. It was necessary to: - decrease the shell stiffness by 30%; - increase the top ring stiffness by 300%; - modify the boundary conditions at the bottom by taking into account the soil impedance. In order to obtain a difference between the measured and the corresponding calculated frequencies less than 1%. The model was then judged to be realistic enough. (author). 23 figs., 13 refs., 1 annex

  20. Sea water for cooling Koeberg

    International Nuclear Information System (INIS)

    The Koeberg-1 reactor under construction will house three separate water cooling systems. The third of these is the sea water cooling system, which draws sea water through the condensers to cool the low pressure steam exhausted by the turbine. The designs of the inlet basin, which provides sea water for the tertiary water cooling system, and the outfall point of the used water back into the sea are described

  1. Thermal performance of cross flow cooling towers in variable wet bulb temperature

    International Nuclear Information System (INIS)

    Cooling towers are widely used in most industrial units to reject waste heat to the atmosphere. Wet towers are usually designed to operate in hot and dry weather conditions with narrow range of wet bulb temperature, but many cooling towers are required to operate in weather condition with large variation of wet bulb temperature which strongly affects the thermal performance of the towers. In this paper a conventional mathematical model is used to predict the thermal behavior of an existing cross flow tower under variable wet bulb temperature and the results are compared with experimental data in various operating conditions. Available fill characteristic curve of the tower is obtained to estimate its departure from the design conditions. It is found that when the wet bulb temperature increases, the approach, range and evaporation loss would increase considerably. Variation of evaporation loss versus wet bulb temperature was estimated. Finally the effect of placing an impact separator in front of air louvers on thermal performance of the tower is investigated.

  2. Performance analysis of heat transfer processes from wet and dry surfaces : cooling towers and heat exchangers

    OpenAIRE

    Hasan, Ala Ali

    2005-01-01

    The objective of this work is to study the thermal and hydraulic performance of evaporatively cooled heat exchangers, including closed wet cooling towers, and dry tube heat exchangers with various geometries. Applications utilising such equipment exist in almost every thermal process. The investigation includes theoretical analysis, computational approaches, and experimental measurements. In this work, a computational model is presented for the thermal performance of closed wet cooling to...

  3. Experimental study of the application of two trickle media for inlet air pre-cooling of natural draft dry cooling towers

    International Nuclear Information System (INIS)

    Highlights: • Two trickle media were experimentally studied in a low-speed wind tunnel. • Correlations for cooling efficiency and pressure drop were developed. • Both trickle media were proven to have relatively low pressure drops. • Both trickle media had severe water entrainment at large air velocities. - Abstract: This paper is part two of a broader investigation into pre-cooling the air that enters natural draft dry cooling towers. Evaporative cooling of air is to some extent different from evaporative cooling of water. Two trickle media (Trickle125 and Trickle100) originally designed for evaporative cooling of water were studied in an open-circuit wind tunnel for evaporative cooling of air. Three medium thicknesses (200, 300 and 450 mm) and two water flow rates (10 and 5 l/min per m2 horizontally exposed surface area) were used in the tests. The air velocities ranged from 0.5 to 3.0 m/s. The cooling efficiency and the pressure drop of the two media were curve fitted to yield a set of correlations. The pressure drop ranges for Trickle125 and Trickle100 were 0.7–50 Pa and 0.6–41.6 Pa, respectively. The cooling efficiencies of Trickle125 and Trickle100 fell within 15.7–55.1% and 11–44.4%, respectively. Generally, media with large effective surfaces provide high cooling efficiencies and high pressure drops; there is a trade-off between cooling efficiency and pressure drop when selecting a particular medium for a specific application. The water entrainment off the media was detected with water-sensitive papers, and both media had severe water entrainment at large air velocities

  4. Semiempirical model of a building with a passive evaporative cool tower

    Energy Technology Data Exchange (ETDEWEB)

    Givoni, B. (Univ. of California, Los Angeles (United States))

    1993-05-01

    An experimental mathematical model that calculates the performance of a passive evaporative cool tower (also known as downdraft evaporative chimney), has been developed by Cunningham and Thompson. The model calculates the tower's exit air temperature, flow rate and the speed of the air exiting from the tower, and the diurnal patterns of the indoor temperature of a lightweight building cooled by this system. Initial validation of the model, by comparing predictions with independent measurements of the indoor temperature of the test building, was done by Cunningham et al. In its present state the applicability of the model is limited to the use of evaporating pads of the type used in the Tucson study (CELdek) cooling a lightweight building (stud wall construction).

  5. Overview of the Chalk Point Cooling Tower Project, 1972-1979

    Energy Technology Data Exchange (ETDEWEB)

    Moon, M.L. (ed.)

    1979-03-01

    The objectives, methodologies, data, and analytical results of the Chalk Point Cooling Tower Program are reviewed. The overview intergrates the concepts and activities of the various program elements to provide a coherent view of the program in its entirety. Samples of the various data acquired are included together with very brief summaries of the conclusions. The report is extensively referenced to provide specific directions to the more extensive treatments of the program, data tabulations, and tape libraries available in the complete library of Chalk Point reports. The Chalk Point data is a resource for the study of cooling tower salt deposition processes and impacts in general. The methods used, while developed to facilitate the assessment of salt drift impact at Chalk Point, also have applicability to cooling tower impact analysis at other sites.

  6. Simultaneous prediction of internal and external aerodynamic and thermal flow fields of a natural-draft cooling tower in a cross-wind

    International Nuclear Information System (INIS)

    The quantitative simulation of cooling-tower performance is useful to designers, enabling them to make optimal choices regarding: the type, volume and shape of the packing (i.e. fill); and the shape and size of the tower. In order to simulate performance realistically, non-uniformities of distribution of water and air mass-flow rates across the tower radius must be taken into account. This necessitates at least 2D modeling; and in order to establish the influence of a cross-wind, boundary conditions must be far away from the tower inlet and outlet, and 3D modeling must be performed. This paper is concerned with large wet natural-draught cooling towers of the type used in many steam power stations for cooling large quantities of water by direct contact with the atmosphere. The aim of the present work has been to improve the procedures of calculation by using numerical integration of the heat and mass transfer equations, and to connect internal and external aerodynamics thus enabling wind influence to be studied. It permits predicting the performance of a proposed design of the tower over a range of operating conditions. PHOENICS, a general-purpose computer code for fluid-flow simulation, is used to provide numerical solutions to governing differential equations

  7. Water cooled reactor

    International Nuclear Information System (INIS)

    Purpose: To attain excellent core cooling performance even when all of the internal pumps for recycling reactor water are stopped. Constitution: Internal pumps provided to a shroud support plate forcively recycle the reactor water to the reactor core supported by the shroud support to cool the reactor core. In this case, hydraulic pressure is applied to the valve bodies of check valves provided to the shroud support plate from the exhaust side of the internal pumps and the valve opening slits formed in the shroud support plate are closed by the valve bodies to thereby prevent the back flow from the exhaust side to the suction side of the internal pumps. When all of the internal pumps are stopped, the check valves are automatically opened to spontaneously circulate a great amount of recycling water by way of the slits. This can avoid the restriction applied to the reactor operation range at low core flow rate region. (Moriyama, K.)

  8. Measurements in natural-draft wet cooling towers at the nuclear power station Philippsburg 1

    International Nuclear Information System (INIS)

    An extensive measuring programme was carried out on the cooling tower of the nuclear power plant Phillipsburg in spring 1980, to simultaneously record all necessary parameters, and to compile the results to complete data sets. The aim of the programme was as follows: - to improve the state of knowledge by means of an extensive interdisciplinary field study, - to verify expert opinions- and calculated predictions (models for operation characteristics, emissions and propagation), - to inform the public of efforts made for environmentally sound cooling tower operation. The work was performed in 8 partial projects by interdisciplinary working groups of scientists. (orig./GL)

  9. WALKUERE - simulation of the vortex-pair structure of cooling tower plumes by a computer program

    International Nuclear Information System (INIS)

    The theoretical fundamentals are presented of the WALKUERE computercode for computation of the three-dimensional rise of cooling tower plumes. Examples demonstrate the distribution of the excess temperature, the additional humidity, the vertical velocity, and the content of rain droplets in the plume, which are calculated by this program. Although, at the time being, only a qualitative comparison is possible with measurements in a cooling tower plume carried out by H. Fortak, it already shows good agreement between experimental and theoretical results. Deficiencies of 1-dimensional models are discussed and the planned further development of the 3-dimensional model is presented. (orig.)

  10. Water Cooled Mirror Design

    Energy Technology Data Exchange (ETDEWEB)

    Dale, Gregory E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Holloway, Michael Andrew [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pulliam, Elias Noel [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-03-30

    This design is intended to replace the current mirror setup being used for the NorthStar Moly 99 project in order to monitor the target coupon. The existing setup has limited movement for camera alignment and is difficult to align properly. This proposed conceptual design for a water cooled mirror will allow for greater thermal transfer between the mirror and the water block. It will also improve positioning of the mirror by using flexible vacuum hosing and a ball head joint capable of a wide range of motion. Incorporating this design into the target monitoring system will provide more efficient cooling of the mirror which will improve the amount of diffraction caused by the heating of the mirror. The process of aligning the mirror for accurate position will be greatly improved by increasing the range of motion by offering six degrees of freedom.

  11. Experimental evaluation of aerodynamic inlet losses in natural draft dry cooling towers

    International Nuclear Information System (INIS)

    The aerodynamic inlet losses at the base of circular natural draft dry cooling towers with horizontal radial and vertical circumferential heat exchanger arrangements, are investigated experimentally. Since the rectangular heat exchanger bundles in the horizontal radial arrangement cannot effectively cover the entire cross-sectional area and do not stretch continuously along the entire circumference of the tower, the inlet loss is found to be dependent on the particular layout. The actual flow pattern before the heat exchangers is found to be complex and unstable under certain geometric conditions. The losses are furthermore found to be dependent on the tower geometry and the heat exchanger flow resistance in the horizontal layout. In the vertical arrangement, the loss is found to be essentially independent of the heat exchanger resistance. By rounding off the inlet to the tower, reductions in inlet flow losses can be achieved under certain conditions

  12. Experimental study regarding the evolution of temperature profiles inside wet cooling tower under cross-wind conditions

    International Nuclear Information System (INIS)

    Based on similarity theory, this research details a thermal-state model experiment, concerning the evolution of the air/water temperature profiles inside a Natural Draft Wet Cooling Tower (NDWCT) under windless and cross-wind conditions. Prior studies have shown that the air/water temperature distribution is fairly uniform and stable under windless (stagnant) conditions, but the uniformity is destroyed in the presence of windy conditions, and the air/water temperature of different points displays a large variation subject to the same cross-wind velocity. Generally speaking, the highest air/water temperature values inside the whole tower lie on the windward and leeward direction, but the highest air temperature at the tower outlet appears near the leeward side zone, rather than exactly on the leeward side. Based on this research, the air/water temperature profiles regarding measurement of values can be obtained accurately under windless and cross-wind conditions, a fact that can help confirm the specific location of vortex on the windward and leeward side. All of above findings can provide an important theoretical foundation concerning further research, specifically for energy-saving aspects NDWCTs. (authors)

  13. Wind dependence on the flow rate in a natural draught cooling tower

    International Nuclear Information System (INIS)

    The efficiency of a natural draught cooling tower depends, among other things, on the effect of the wind on the flow in the tower stack. Determinations were made on a natural draught wet cooling tower 100 metres high, for the purpose of studying this effects. As characteristic quantity, a typical height was determined, the values of which were worked out from the results of the measurements. The efficiency of the stack is affected the most in the case of average wind velocities (when the velocity of the wind is about equal to the mean velocity of the plume). This effect diminishes when the velocity of the wind increases. In the case of average wind velocities, the direction of the wind has an effect, owing to the neighbouring buildings; for slightly greater wind velocities, no effect could be found

  14. Use of Air2Air Technology to Recover Fresh-Water from the Normal Evaporative Cooling Loss at Coal-Based Thermoelectric Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Ken Mortensen

    2009-06-30

    This program was undertaken to build and operate the first Air2Air{trademark} Water Conservation Cooling Tower at a power plant, giving a validated basis and capability for water conservation by this method. Air2Air{trademark} water conservation technology recovers a portion of the traditional cooling tower evaporate. The Condensing Module provides an air-to-air heat exchanger above the wet fill media, extracting the heat from the hot saturated moist air leaving in the cooling tower and condensing water. The rate of evaporate water recovery is typically 10%-25% annually, depending on the cooling tower location (climate).

  15. Phototrophic biofilms on the interior walls of concrete Iterson-type cooling towers.

    Czech Academy of Sciences Publication Activity Database

    Hauer, Tomáš

    2010-01-01

    Ro?. 22, ?. 6 (2010), s. 733-736. ISSN 0921-8971 R&D Projects: GA ?R GA206/08/0318 Institutional research plan: CEZ:AV0Z60050516 Keywords : cyanobacteria * algae * cooling towers Subject RIV: EF - Botanics Impact factor: 1.792, year: 2010

  16. A model for radionuclide transport in the Cooling Water System

    International Nuclear Information System (INIS)

    A radionuclide transport model developed to assess radiological levels in the K-reactor Cooling Water System (CWS) in the event of an inadvertent process water (PW) leakage to the cooling water (CW) in the heat exchangers (HX) is described. During and following a process water leak, the radionuclide transport model determines the time-dependent release rates of radionuclide from the cooling water system to the environment via evaporation to the atmosphere and blow-down to the Savannah River. The developed model allows for delay times associated with the transport of the cooling water radioactivity through cooling water system components. Additionally, this model simulates the time-dependent behavior of radionuclides levels in various CWS components. The developed model is incorporated into the K-reactor Cooling Tower Activity (KCTA) code. KCTA allows the accident (heat exchanger leak rate) and the cooling tower blow-down and evaporation rates to be described as time-dependent functions. Thus, the postulated leak and the consequence of the assumed leak can be modelled realistically. This model is the first of three models to be ultimately assembled to form a comprehensive Liquid Pathway Activity System (LPAS). LPAS will offer integrated formation, transport, deposition, and release estimates for radionuclides formed in a SRS facility. Process water and river water modules are forthcoming as input and downstream components, respectively, for KCTA

  17. Influence of building and supply conditions on coolant pumps and the various coolant pump designs for cooling towers

    International Nuclear Information System (INIS)

    This contribution tries to present the various factors influencing the design of cooling tower pumps. As cooling tower pumps are very often designed as concrete speral casing pumps, the suction bend construction often offers itself. The running wheel of cooling tower pumps is usually of semi-axial design, whereby one has to differ between rigid, adjustable, and resetable running wheels. Finally, the type of cooling system and the nominal width are decisive for either the construction type of the spiral casing pump or the tubular type pump. Both methods are compared in a critical way. (orig.)

  18. Cooling water requirements and nuclear power plants

    International Nuclear Information System (INIS)

    Indian nuclear power programme is poised to scuttle the energy crisis of our time by proposing joint ventures for large power plants. Large fossil/nuclear power plants (NPPs) rely upon water for cooling and are therefore located near coastal areas. The amount of water a power station uses and consumes depends on the cooling technology used. Depending on the cooling technology utilized, per megawatt existing NPPs use and consume more water (by a factor of 1.25) than power stations using other fuel sources. In this context the distinction between 'use' and 'consume' of water is important. All power stations do consume some of the water they use; this is generally lost as evaporation. Cooling systems are basically of two types; Closed cycle and Once-through, of the two systems, the closed cycle uses about 2-3% of the water volumes used by the once-through system. Generally, water used for power plant cooling is chemically altered for purposes of extending the useful life of equipment and to ensure efficient operation. The used chemicals effluent will be added to the cooling water discharge. Thus water quality impacts on power plants vary significantly, from one electricity generating technology to another. In light of massive expansion of nuclear power programme there is a need to develop new ecofriendly cooling water technologies. Seawater cooling towers (SCT) could be a viable option for power plants. SCTs can be utilized with the proper selection of materials, coatings and can achieve long service life. Among the concerns raised about the development of a nuclear power industry, the amount of water consumed by nuclear power plants compared with other power stations is of relevance in light of the warming surface seawater temperatures. A 1000 MW power plant uses per day ?800 ML/MW in once through cooling system; while SCT use 27 ML/MW. With the advent of new marine materials and concrete compositions SCT can be constructed for efficient operation. However, the concentration of salts usually encountered in seawater need to be properly rated for better thermal performance of SCTs. This paper addresses the basic and applied aspects of seawater cooling technology in the context of NPPs to orient towards SCTs. (author)

  19. Cooling water injection system

    International Nuclear Information System (INIS)

    In a BWR type reactor, ECCS system is constituted as a so-called stand-by system which is not used during usual operation and there is a significant discontinuity in relation with the usual system. It is extremely important that ECCS operates upon occurrence of accidents just as specified. In view of the above in the present invention, the stand-by system is disposed along the same line with the usual system. That is, a driving water supply pump for supplying driving water to a jet pump is driven by a driving mechanism. The driving mechanism drives continuously the driving water supply pump in a case if an expected accident such as loss of the function of the water supply pump, as well as during normal operation. That is, all of the water supply pump, jet pump, driving water supply pump and driving mechanism therefor are caused to operate also during normal operation. The operation of them are not initiated upon accident. Thus, the cooling water injection system can perform at high reliability to remarkably improve the plant safety. (K.M.)

  20. Mathematical model of drift deposition from a bifurcated cooling tower plume

    International Nuclear Information System (INIS)

    Cooling tower drift deposition modeling has been extended by including centrifugal force induced through plume bifurcation in a crosswind as a mechanism for drift droplet removal from the plume. The model, in its current state of development, is capable of predicting the trajectory of a single droplet from the stage of strong interaction with the vortex field soon after droplet emission at the tower top through the stage of droplet evaporation in an unsaturated atmosphere after droplet breakaway from the plume. The computer program developed from the mathematical formulation has been used to explore the dependency of the droplet trajectory on droplet size, vortex strength, point of droplet emission, drag coefficient, droplet efflux speed, and ambient conditions. A specific application to drift from a mechanical-draft cooling tower (for a wind speed twice the efflux speed, a relative humidity of 70 per cent, and an initial droplet radius of 100 ?m) showed the droplet to follow a helical trajectory within the plume, with breakaway occurring at 2.5 tower diameters downwind and ground impact of the droplet (reduced through evaporation to 55 ?m radius) at 11 tower diameters

  1. Water cooled nuclear reactor

    International Nuclear Information System (INIS)

    The pressure vessel is divided by a transverse separating wall above the core into a high pressure and a low pressure plenum chamber. The cooling water flows vertically from below upwards through the core, so that hydraulic lifting forces act on the core. To compensate for these forces a core holding down device, consisting of a pressure piston system is provided. The piston surface is at the pressure of the upper high pressure plenum chamber, while the piston rod acts through the separating wall inside a sealing cylinder on the fuel elements in the core. (DG)

  2. Water cooled nuclear reactor

    International Nuclear Information System (INIS)

    In the reactor operating with supercritical pressure and temperature part of the water flowing through the moderator tubes is deflected at the outlet and mixed with a residual partial flow of the coolant fed into the core as well as passed along the fuel rods in opposite direction. By special guiding of the flow downward through the guide tubes of the control rods insertion of the control rods is simplified because of reduced frictional forces. By this means it is also achieved to design less critical the control rod cooling with respect to flow rate control and operating behavior in case of a scram. (orig.)

  3. Design and construction of the cooling tower at the Niederaussem power plant, unit K

    Energy Technology Data Exchange (ETDEWEB)

    Busch, D. [RWE Plus AG, Essen (Germany)

    2001-07-01

    The world's largest natural draught cooling tower is currently being erected at the Niederaussem site western of Cologne/Germany. The construction works started in 1998, and the tower is scheduled to be completed in 2001. The paper is describing the planning stage and erection of the cooling tower shell. The climbing form work for the shell was in March 1999, and the concrete works were completed with the upper ring beam in February 2000. The construction of the shell reached beyond the experience made until then: The size, i.e. height of 200 metres and surface of 60 000 m{sup 3}, is larger than any other cooling tower built before and the concrete has not been lined for the first time although the volume amounts to 17 500 m{sup 3} and the cleaned flue gases are discharged via the cooling tower. (orig.) [German] Zurzeit entsteht in der Gemeinde Niederaussem, westlich von Koeln, der weltgroesste Naturkuehlturm. Baubeginn war 1998, die Fertigstellung ist fuer 2001 geplant. Der Beitrag berichtet ueber die Planung und den Bau der Kuehlturmschale. Kletterbeginn fuer die Schale war Maerz 1999 und die Betonierarbeiten wurden mit der Fertigstellung des oberen Randgliedes im Februar 2000 abgeschlossen. Beim Bau der Schale ist auf zwei Gebieten der bisherige Erfahrungsbereich verlassen worden: Die Schale ueberragt mit einer Hoehe von 200 m und einer Flaeche von ueber 60 000 m{sup 3} alle bisher gebauten Kuehltuerme, und zum ersten Mal wird bei einem Volumen von 17 500 m{sup 3} ein Beton eingesetzt, bei dem auf eine Beschichtung verzichtet wird, obwohl die gereinigten Rauchgase in den Kuehlturm geleitet werden. (orig.)

  4. Energy penalty analysis of possible cooling water intake structurerequirements on existing coal-fired power plants.

    Energy Technology Data Exchange (ETDEWEB)

    Veil, J. A.; Littleton, D. J.; Gross, R. W.; Smith, D. N.; Parsons, E.L., Jr.; Shelton, W. W.; Feeley, T. J.; McGurl, G. V.

    2006-11-27

    Section 316(b) of the Clean Water Act requires that cooling water intake structures must reflect the best technology available for minimizing adverse environmental impact. Many existing power plants in the United States utilize once-through cooling systems to condense steam. Once-through systems withdraw large volumes (often hundreds of millions of gallons per day) of water from surface water bodies. As the water is withdrawn, fish and other aquatic organisms can be trapped against the screens or other parts of the intake structure (impingement) or if small enough, can pass through the intake structure and be transported through the cooling system to the condenser (entrainment). Both of these processes can injure or kill the organisms. EPA adopted 316(b) regulations for new facilities (Phase I) on December 18, 2001. Under the final rule, most new facilities could be expected to install recirculating cooling systems, primarily wet cooling towers. The EPA Administrator signed proposed 316(b) regulations for existing facilities (Phase II) on February 28, 2002. The lead option in this proposal would allow most existing facilities to achieve compliance without requiring them to convert once-through cooling systems to recirculating systems. However, one of the alternate options being proposed would require recirculating cooling in selected plants. EPA is considering various options to determine best technology available. Among the options under consideration are wet-cooling towers and dry-cooling towers. Both types of towers are considered to be part of recirculating cooling systems, in which the cooling water is continuously recycled from the condenser, where it absorbs heat by cooling and condensing steam, to the tower, where it rejects heat to the atmosphere before returning to the condenser. Some water is lost to evaporation (wet tower only) and other water is removed from the recirculating system as a blow down stream to control the building up of suspended and dissolved solids. Makeup water is withdrawn, usually from surface water bodies, to replace the lost water. The volume of makeup water is many times smaller than the volume needed to operate a once-through system. Although neither the final new facility rule nor the proposed existing facility rule require dry cooling towers as the national best technology available, the environmental community and several States have supported the use of dry-cooling technology as the appropriate technology for addressing adverse environmental impacts. It is possible that the requirements included in the new facility rule and the ongoing push for dry cooling systems by some stakeholders may have a role in shaping the rule for existing facilities. The temperature of the cooling water entering the condenser affects the performance of the turbine--the cooler the temperature, the better the performance. This is because the cooling water temperature affects the level of vacuum at the discharge of the steam turbine. As cooling water temperatures decrease, a higher vacuum can be produced and additional energy can be extracted. On an annual average, once-through cooling water has a lower temperature than recirculated water from a cooling tower. By switching a once-through cooling system to a cooling tower, less energy can be generated by the power plant from the same amount of fuel. This reduction in energy output is known as the energy penalty. If a switch away from once-through cooling is broadly implemented through a final 316(b) rule or other regulatory initiatives, the energy penalty could result in adverse effects on energy supplies. Therefore, in accordance with the recommendations of the Report of the National Energy Policy Development Group (better known as the May 2001 National Energy Policy), the U.S. Department of Energy (DOE), through its Office of Fossil Energy, National Energy Technology Laboratory (NETL), and Argonne National Laboratory (ANL), has studied the energy penalty resulting from converting plants with once-through cooling to wet towers or indirect-dry towers. Five l

  5. Cooling clothing utilizing water evaporation

    DEFF Research Database (Denmark)

    Sakoi, Tomonori; Tominaga, Naoto

    2014-01-01

    We developed cooling clothing that utilizes water evaporation to cool the human body and has a mechanism to control the cooling intensity. Clean water was supplied to the outer surface of the T-shirt of the cooling clothing, and a small fan was used to enhance evaporation on this outer surface. To prevent wet discomfort, the T-shirt was made of a polyester material having a water-repellent silicon coating on the inner surface. The chest, front upper arms, and nape of the neck were adopted as the cooling areas of the human body. We conducted human subject experiments in an office with air temperature ranging from 27.4 to 30.7 °C to establish a suitable water supply control method. A water supply control method that prevents water accumulation in the T-shirt and water dribbling was validated; this method is established based on the concept of the water evaporation capacity under the applied environment.

  6. The influence of the finned-tube assembly on the dimensions of natural-draft dry-type cooling towers

    International Nuclear Information System (INIS)

    For various heat exchanger systems the required heights of the towers are evaluated by means of a simplifying mathematical model for dimensioning cooling towers. The characteristics of the cooling systems are for each case taken from literature. The number of tube banks of the heat exchanger systems in flow direction was optimized using the operational data of the Schnehausen dry-type cooling tower. It may be assumed that by changing the tube configuration the performance of very closely spaced, aligned finned systems can be considerably improved. (GL)

  7. Construction and operation of natural draught cooling towers made of highly acid-resistant concrete; Bau und Betrieb von Naturzugkuehltuermen aus Beton mit erhoehtem Saeurewiderstand

    Energy Technology Data Exchange (ETDEWEB)

    Niepel, A. [RWE Power AG, Kraftwerk Niederaussem, Bergheim (Germany); Huettl, R. [Materialpruefungsanstalt Berlin-Brandenburg GmbH, Berlin (Germany); Kloeker, T.; Meyer, J. [Zerna Ingenieure GmbH, Bochum (Germany); Busch, D.

    2007-07-01

    In 1999 the construction of the first cooling tower shell using highly acid-resistant concrete started at the RWE power station of Niederaussem. This type of concrete was developed after four years of research to avoid the necessary coating of the inner cooling tower shell due to the discharge of flue gases via cooling tower. The positive experience led RWE Power to build two more cooling towers of this type at the power station of Neurath and even order four more cooling towers for two planned power stations in the west and southwest of Germany. (orig.)

  8. Calder Hall Cooling Tower Demolition: Landmark Milestone for Decommissioning at Sellafield

    International Nuclear Information System (INIS)

    September 2007 saw a very visible change to the Sellafield site following the culmination of a major decommissioning project; the demolition of the four Calder Hall cooling towers. A key part of the UK's nuclear industrial heritage, Calder Hall, the world's first commercial nuclear power station, was opened by Her Majesty Queen Elizabeth II in October 1953 and continued to generate electricity until its closure in 2003. Following the decision to decommission the Calder Hall site, explosive demolition was identified as the safest and most cost effective route for the removal of the towers. The technique, involving the placement of explosive in 60% of the circumference of both shell and legs, is a tried and tested method which had already been used successfully in more than 200 cooling towers in the UK in the last 30 years. The location and composition of the four 88 metre high towers also created additional challenges. Situated only 40 metres away from the UK's only nuclear Fuel Handling Plant, as well as other sensitive structures on the Sellafield site, the project had to address the impact of a number of key areas, including dust, ground vibration and air over pressure, to ensure that the demolition could be carried out safely and without significant impact on other operational areas on the site. At the same time, the towers had to be prepared for demolition in a way that minimised the amounts of radioactive or hazardous waste materials arising. This paper follows the four year journey from the initial decision to demolish the towers right through to the demolition itself as well as the clean up of the site post demolition. It will also consider the massive programme of work necessary not only to carry out the physical work safely but also to gain regulatory confidence and stakeholder support to carry out the project successfully. In summary: The demolition of the four Calder Hall cooling towers was a highly visible symbol of the changes that are occurring on the Sellafield site as it moves forward towards a decommissioning future. Although in itself the demolition was both straightforward and standard, the various complexities posed by the towers situation at Sellafield introduced an entirely new element to the project, with a number of complex challenges which had to be overcome or resolved before the demolition could take place. It is a testament to the skill and dedication of the project team and its associated contractors that the project was delivered safely and successfully without a single accident, injury or event throughout the entire four years, and with minimal impact on both site operations and the local community. (authors)

  9. Experimental study of crosswind effects on the performance of small cylindrical natural draft dry cooling towers

    International Nuclear Information System (INIS)

    Highlights: • A 1:12.5 scaled NDDCT model equipped with a round electric heater has been tested in a wind tunnel. • The experimental results match well with those of the same-size CFD cooling tower model. • The experiment verifies that the reversed hot airflow exists near the heat exchanger. • The heat dumping of NDDCTs under crosswind is a combination of a natural convection and a forced one. • In small NDDCTs, the forced convection is comparable with the natural convection under fast winds. - Abstract: Crosswind effect is a common issue which limits the cooling efficiency of natural draft dry cooling towers (NDDCTs) of all sizes. On short NDDCTs with total heights less than 30 m, this effect might be much more significant. Following the authors’ previous numerical investigation on crosswind effects in a 15 m-tall cylindrical NDDCT, an experimental study was carried out and is presented in this paper. The study used a 1:12.5 scaled cooling tower model equipped with an electric resistance heater simulating horizontally placed heat exchangers. The air velocity, temperature, and the heat input on the model were measured at different crosswind speeds in a wind tunnel. Comparisons against CFD models show good agreement between the experimental and numerical results when the similarity conditions between the CFD model and the experimental model are fully satisfied. Based on these results, the total heat transfer rate of NDDCTs was proposed to be a combination of a natural convective heat transfer term and a forced convective one. In small cooling towers, the natural convection term is comparable with the forced convection term. This explains why the correlation of the total heat transfer with the wind speed has a turnabout point below which the heat transfer decreases with increasing crosswind speed and above which it does the reverse. The turnabout point occurs when the sum of natural and forced convection terms is the minimum

  10. Effects of discharge recirculation in cooling towers on energy efficiency and visible plume potential of chilling plants

    International Nuclear Information System (INIS)

    Due to limited space and/or improper placement of evaporative cooling towers, discharge recirculation likely occurs in practical applications. The air recirculation may adversely affect energy efficiency of the chilling plants and increase the potential of visible plume around the towers. In this study, the amount of recirculation in a counter-flow cooling tower is evaluated by computational fluid dynamics (CFD) simulation tests under different enclosure structures and crosswind conditions. Then the effects of recirculation in cooling towers on energy performance of a chilling plant and plume potential are investigated. The evaluation is conducted on a dynamic simulation platform using the weather data in a typical meteorological year of Hong Kong. Results show that crosswind can enhance recirculation in cooling towers under lower air flow rate conditions. The recirculation ratio can reach up to 15%. Results also reveal that air recirculation in cooling towers could result in the increase of overall chilling plant energy consumption by over 1.5%. The recirculation also results in significant increase of plume occurrence frequency, particularly in spring season. - Highlights: ? Discharge recirculation in a cooling tower is evaluated by CFD modeling. ? The recirculation ratio can reach up to 15%. ? The recirculation can increase the overall chilling plant energy consumption by over 1.5%. ? The recirculation can significantly increase the plume occurrence frequency.

  11. Methodology for evaluation of cooling tower performance - Part 2: Application of the methodology and computational aspects of Poppe equations

    International Nuclear Information System (INIS)

    Highlights: ? Application of the methodology for evaluation of CT performance is presented. ? Proposed is calculation procedure that minimizes systematic error of applied models. ? Faster numerical integration of Poppe equations is presented. ? Study is based on measured data from a plant and natural draft CT. ? Significance of efficient CT operation and its impact on power output are depicted. - Abstract: A methodology for evaluation of natural draft cooling tower (CT) performance and its application is presented. The study establishes the connection between CT performance and power output. It can estimate a change in a CT's efficiency as well as an increase in power output as a function of cooling water temperature and load to the plant. The methodology consists of three subparts, i.e. Cooling Tower Profiler (CTP) method, CT model and a model of the power plant that are described in the first part of the paper. The second part focuses on application of the methodology in a way that minimizes error of the CT model. One week of data from the power plant were acquired for the analysis. In the CT a small area with irregularities was examined, and increased efficiency and power output are estimated by the methodology. Furthermore, another aspect of solving Poppe equations is examined resulting in reduced computational effort by approximately a half without losing any computational accuracy.

  12. Methodology for evaluation of cooling tower performance - Part 2: Application of the methodology and computational aspects of Poppe equations

    Energy Technology Data Exchange (ETDEWEB)

    Smrekar, J., E-mail: jure.smrekar@uis.no [Department of Mechanical and Structural Engineering and Materials Science, University of Stavanger, 4036 Stavanger (Norway); Senegacnik, A. [Department of Power Engineering, University of Ljubljana, Askerceva 6, SI-1000 Ljubljana (Slovenia); Fuehrer, C. [Department of Numerical Analysis, Lund University, P.O. Box 118, SE 22100 Lund (Sweden)

    2011-10-15

    Highlights: {yields} Application of the methodology for evaluation of CT performance is presented. {yields} Proposed is calculation procedure that minimizes systematic error of applied models. {yields} Faster numerical integration of Poppe equations is presented. {yields} Study is based on measured data from a plant and natural draft CT. {yields} Significance of efficient CT operation and its impact on power output are depicted. - Abstract: A methodology for evaluation of natural draft cooling tower (CT) performance and its application is presented. The study establishes the connection between CT performance and power output. It can estimate a change in a CT's efficiency as well as an increase in power output as a function of cooling water temperature and load to the plant. The methodology consists of three subparts, i.e. Cooling Tower Profiler (CTP) method, CT model and a model of the power plant that are described in the first part of the paper. The second part focuses on application of the methodology in a way that minimizes error of the CT model. One week of data from the power plant were acquired for the analysis. In the CT a small area with irregularities was examined, and increased efficiency and power output are estimated by the methodology. Furthermore, another aspect of solving Poppe equations is examined resulting in reduced computational effort by approximately a half without losing any computational accuracy.

  13. Influence of Flow Rotation Within a Cooling Tower on the Aerodynamic Interaction with Crosswind Flow

    Science.gov (United States)

    Kashani, M. M. Hemmasian; Dobrego, K. V.

    2014-03-01

    Environmental crosswind changes the aerodynamic pattern inside a cooling tower, destroys uniform and axisymmetric distribution of flow at its inlet and outlet, and may degrade fill zone performance. In this paper, the effect of flow rotation in the over-shower zone of a natural draft cooling tower (NDCT) on the aerodynamic interaction with crosswind is studied numerically. The 3D geometry of an actual NDCT and three models of induced rotation velocity fields are utilized for simulation. It is demonstrated that flow rotation results in homogenization of the aerodynamic field in the over-shower zone. The inhomogeneity of the velocity field in the outlet cross section decreases linearly with rotation intensification. The effect of main stream switching under strong wind conditions is found. It is shown that even moderate flow rotation eliminates this effect.

  14. Proposal for the award of a contract for the construction of cooling-tower structures

    CERN Document Server

    1999-01-01

    This document concerns the award of a contract for the construction of reinforced-concrete cooling-tower structures at LHC Point 1. Following a market survey carried out among 79 firms in 17 Member States, a call for tenders (IT-2710/ST/LHC) was sent on 13 August 1999 to eight firms and two consortia, both consisting of three firms, in eight Member States. By the closing date, CERN had received four tenders. The Finance Committee is invited to agree to the negotiation of a contract for the construction of reinforced-concrete cooling towers at LHC Point 1 with the consortium PAT (AT), BARESEL (DE) and ZSCHOKKE LOCHER (CH), the lowest bidder complying with the specification, for an amount of 3 393 493 Swiss francs, not subject to revision. The consortium has indicated the following distribution by country of the supply covered by this adjudication proposal: BE-60%, AT-18%, CH-11% and DE-11%.

  15. Proposal for the award of a contract for the upgrade of the SPS cooling towers

    CERN Document Server

    2000-01-01

    This document concerns the award of a contract for the upgrade of the SPS cooling towers. Following a market survey carried out among 56 firms in sixteen Member States, a call for tenders (IT-2740/ST/SPS) was sent on 14 February 2000 to 10 firms in six Member States. By the closing date, CERN had received seven tenders from seven firms. The Finance Committee is invited to agree to the negotiation of a contract with SPIG (IT), the lowest bidder, for the upgrade of the SPS cooling towers, for an amount of 1 073 757 Swiss francs, not subject to revision. SPIG has indicated the following distribution by country of the contract value covered by this adjudication proposal: IT-73%; FI-24%; DE-3%.

  16. SIMULATION AND VIBRATION ANALYSIS OF GEAR BOX USED IN COOLING TOWER FAN

    Directory of Open Access Journals (Sweden)

    K.G.Patel

    2015-02-01

    Full Text Available Vibration and cross wind pressure are suspected as the major reason for the failure of the gear box of the cooling tower fan. Also, Vibration suppression of rotating machinery is an important engineering problem. In the present thesis work, I have done a study of the mathematical modeling of gear box of cooling tower fan, target setting for vibration & noise refinement in a system, and investigated various modes of active & passive vibration control techniques. This thesis presents a novel approach to determine the noise and vibration characteristics by predicting the vibration response of a rotating mechanism through data obtained by vibration simulation of a CAD model. Vibration analysis is widely used in industry for condition monitoring of a variety of machines and components. The simulation is then compared to a real-life testing & the 2 results are compared. The experiments are performed for pre-determined loading conditions.

  17. Statistical study on meteorological effects due to the cooling tower of Goesgen

    International Nuclear Information System (INIS)

    A specific statistical method has been developed to study the effects of a cooling tower plume on local meteorological parameters. It is based on the comparison of hourly meteorological measurements, made simultaneously at stations near the cooling tower and in other stations unaffected by the plume. To study the reduction of sunshine duration due to the shadowing of the plume, measurements from two stations situated within a radius of about 1 km eastward and westward of the power station are compared. In clear weather, only one of these two stations usually lays in the shadow of the plume. Statistical treatment of differences detected in temperature, humidity, precipitation, sunshine duration and solar radiation shows systematic results, observed mainly when the power station is active. It appears that the effects on sunshine duration are the most important, followed by the influence on solar radiation. Differences in temperature and humidity are also detectable. No relevant influences have been found on precipitation

  18. Reliability Analysis of Cooling Towers: Influence of Rebars Corrosion on Failure

    International Nuclear Information System (INIS)

    Natural-draught cooling towers are used in nuclear power plants as heat exchangers. These structures are submitted to environmental loads such as wind and thermal gradients that are stochastic in nature. A probabilistic framework has been developed by EDF (Electricite de France) for assessing the durability of such structures. In this paper, the corrosion of the rebars due to concrete carbonation and the corresponding weakening of the reinforced concrete sections is considered. Due to the presence of time in the definition of the limit state function associated with the loss of serviceability of the cooling tower, time-variant reliability analysis has to be used. A novel approach is proposed to take into account the random 'initiation time', which corresponds to the time necessary for the carbonation to attain the rebars. Results are given in terms of the probability of failure of the structure over its life time. (authors)

  19. Flue gas discharge through cooling towers. Measurements at the pilot power plant Voelklingen of the Saarbergwerke AG

    Energy Technology Data Exchange (ETDEWEB)

    Leidinger, B.; Natusch, K.; Scholl, G.

    1985-10-01

    The flue gases are cooled in wet desulphurization plants. This enables the combined discharge of the cleaned gases mixed with the air from the cooling tower through natural draught-wet cooling towers. The favourable rising behaviour and the compact coherence of the cooling tower vapour are employed to spread the flue gases loaded with the remaining amounts of noxious matter. In power station units which are not equipped with natural draught-wet cooling towers the cleaned flue gases have to be heated up and discharged through high chimneys. - So far, the only plant that has realized the combined discharge of flue gases and cooling tower vapour is the Pilot Power Plant Voelklingen of the Saarbergwerke AG. Two extensive measuring campaigns run by the Rheinisch Westfaelisches Elektrizitaetswerk AG and by the Saarbergwerke AG. proved the variant of the cooling tower to be a favourble alternative to the variant of the chimneys which have been used so far with regard to immissions. During the taking of the measurements and extensive picture of the operational behaviour of the plant, the condition of the emission and their spreading into the atmosphere was gained. (orig.).

  20. The influence of inlet system and inlet conditions on the cooling pumps and on the different types of coolant pumps for cooling towers

    International Nuclear Information System (INIS)

    The paper attempts to give the influencing parameters determining the type of cooling pump to be constructed. As cooling pumps are often constructed as pumps with a spiral concrete housing, the suction bend construction appears to be the most suitable. The impeller of cooling tower pumps is usually semiaxial. The type of pump - pump with spiral housing or pump with tubular housing - is determined by the cooling process and the nominal bore of the pump. Of the control techniques known, rotor blade control and inlet vane control are suitable for cooling tower pumps. The two methods of control are critically compared. (orig.)

  1. Cooling clothing utilizing water evaporation

    DEFF Research Database (Denmark)

    Sakoi, Tomonori; Tominaga, Naoto; Melikov, Arsen Krikor; Kolencíková, Sona

    2014-01-01

    We developed cooling clothing that utilizes water evaporation to cool the human body and has a mechanism to control the cooling intensity. Clean water was supplied to the outer surface of the T-shirt of the cooling clothing, and a small fan was used to enhance evaporation on this outer surface. To prevent wet discomfort, the T-shirt was made of a polyester material having a water-repellent silicon coating on the inner surface. The chest, front upper arms, and nape of the neck were adopted as the...

  2. From large natural draft cooling tower shells to chimneys of solar upwind power plants

    OpenAIRE

    KRAETZIG, Wilfried B.; HARTE, Reinhard; MONTAG, Ulrich; WOERMANN, Ralf

    2009-01-01

    Natural draft cooling towers (NDCTs) presently form the world-largest RC shell structures, solar updraft power plants (SUPPs) will do this in future. The paper starts with explanations of the working principles of NDCTs and SUPPs. In industrialized countries with strong legal emphasis on sustainable power production technologies, NDCTs are widely spread, while SUPPs represent future solar power generation concepts in the world¿s tropical areas, using solar irradiation as power plant fuel. Con...

  3. Three-dimensional calculations of plumes in the near field of a cooling tower

    International Nuclear Information System (INIS)

    This paper shows a comparison between 3D computation and some results of scale models experiments in the near field of a cooling tower. We compare the velocity and temperature fields and we found a rather good agreement with the measurements. The rough description of the shell in the computation gives rise to a pressure field which has not the same intensity as the measured field

  4. Large natural draught cooling towers of reinforced concrete - present state and future developments

    International Nuclear Information System (INIS)

    The paper attempts to give a survey of the present state of safety theory as well as of construction and erection of reinforced-concrete natural draught cooling towers. Today these constructions have reached heights of over 150 m and may be built still higher. From the point of view of safety and relibility this is undoubtedly possible. From an economical point of view, new constructional elements will probably have to be introduced into the design. (orig./AK)

  5. Prediction of ground vibration due to the collapse of a 235 m high cooling tower under accidental loads

    International Nuclear Information System (INIS)

    Highlights: ? Ground vibration due to the collapse of a huge cooling tower was predicted. ? Accidental loads with different characteristics caused different collapse modes. ? Effect of ground vibration on the nuclear-related facilities cannot be ignored. -- Abstract: A comprehensive approach is presented in this study for the prediction of the ground vibration due to the collapse of a 235 m high cooling tower, which can be caused by various accidental loads, e.g., explosion or strong wind. The predicted ground motion is to be used in the safety evaluation of nuclear-related facilities adjacent to the cooling tower, as well as the plant planning of a nuclear power station to be constructed in China. Firstly, falling weight tests were conducted at a construction site using the dynamic compaction method. The ground vibrations were measured in the form of acceleration time history. A finite element method based “falling weight-soil” model was then developed and verified by field test results. Meanwhile, the simulated collapse processes of the cooling tower under two accidental loads were completed in a parallel study, the results of which are briefly introduced in this paper. Furthermore, based on the “falling weight-soil” model, “cooling tower-soil” models were developed for the prediction of the ground vibrations induced by two collapse modes of the cooling tower. Finally, for a deep understanding of the vibration characteristics, a parametric study was also conducted with consideration of different collapse profiles, soil geologies as well as the arrangements of an isolation trench. It was found that severe ground vibration occurred in the vicinity of the cooling tower when the collapse happened. However, the vibration attenuated rapidly with the increase in distance from the cooling tower. Moreover, the “collapse in integrity” mode and the rock foundation contributed to exciting intense ground vibration. By appropriately arranging an isolation trench, the ground vibration can be significantly reduced

  6. Improvements achieved in the cooling tower performance at the Leibstadt Nuclear Power Plant

    International Nuclear Information System (INIS)

    Appreciable improvements in the overall efficiency of various power plants can be obtained by modifications at the cold end of the thermal cycle. This paper summarizes new methods of analysis of this part of the plant and how these have successfully been used at the Leibstadt Nuclear Power Plant. The relatively low cost of performing these modifications has led to an investment pay back time of only 2 months. The problem of non optimum design of the cooling systems, cooling towers, condenser evacuation systems etc. seems to be caused generically by the lack of adequate engineering tools at the time the plants were built

  7. Application of an Optimum Design of Cooling Water System by Regeneration Concept and Pinch Technology for Water and Energy Conservation

    OpenAIRE

    Ataei, A.; M.H. Panjeshahi; Parand, R.; N. Tahouni

    2009-01-01

    In this study, using a combination of Pinch Technology and Mathematical Programming, a new technique is presented in order to grass-root design for a cooling water system to achieve minimum total annual cost. The presented technique is further improved by using patterns from the concept of regeneration recycling in water systems; in a sense that cooling water is regenerated locally by an air cooler. Moreover, in the proposed method, optimum design of cooling tower has been achieved thr...

  8. Predicted and observed cooling tower plume rise and visible plume length at the John E. Amos power plant

    International Nuclear Information System (INIS)

    A one-dimensional numerical cloud growth model and several empirical models for plume rise and cloud growth are compared with twenty-seven sets of observations of cooling tower plumes from the 2900 MW John E. Amos fossil-fuel power plant in West Virginia. The three natural draft cooling towers are 200m apart. In a cross wind, the plumes begin to merge at a distance of about 500m downwind. In calm conditions, with reduced entrainment, the plumes often do not merge until heights of 1000m. The average plume rise, 750m, is predicted well by the models, but day-to-day variations are simulated with a correlation coefficient of about .5. Model predictions of visible plume length agree, on the average, with observations for visible plumes of short to moderate length (less than about 1km). The prediction of longer plumes is hampered by our lack of knowledge of plume spreading after the plumes level off. Cloud water concentrations predicted by the numerical model agree with those measured in natural cumulus clouds

  9. 18 CFR 420.44 - Cooling water.

    Science.gov (United States)

    2010-04-01

    ... 2010-04-01 2010-04-01 false Cooling water. 420.44 Section 420.44 Conservation...CHARGES Charges; Exemptions § 420.44 Cooling water. Water used exclusively for cooling purposes which is returned to the...

  10. Reconstruction of the process towers at the Glace Bay heavy water plant

    International Nuclear Information System (INIS)

    Certain aspects of the rehabilitation of the Glace Bay heavy water plant are described, primarily the rebuilding of the process towers. Preparation of used materials for reuse is described, along with tower stability, materials of construction, rehabilitation of tower walls and welds, redesign of joints, stress relieving, and hydrostatic testing. (E.C.B.)

  11. Quasi One-Dimensional Model of Natural Draft Wet-Cooling Tower Flow, Heat and Mass Transfer

    Directory of Open Access Journals (Sweden)

    Hyhlík Tomáš

    2015-01-01

    Full Text Available The article deals with the development of CFD (Computational Fluid Dynamics model of natural draft wet-cooling tower flow, heat and mass transfer. The moist air flow is described by the system of conservation laws along with additional equations. Moist air is assumed to be homogeneous mixture of dry air and water vapour. Liquid phase in the fill zone is described by the system of ordinary differential equations. Boundary value problem for the system of conservation laws is discretized in space using Kurganov-Tadmor central scheme and in time using strong stability preserving Runge-Kutta scheme. Initial value problems in the fill zone is solved by using standard fourth order Runge-Kutta scheme. The interaction between liquid water and moist air is done by source terms in governing equations.

  12. Quasi One-Dimensional Model of Natural Draft Wet-Cooling Tower Flow, Heat and Mass Transfer

    Science.gov (United States)

    Hyhlík, Tomáš

    2015-05-01

    The article deals with the development of CFD (Computational Fluid Dynamics) model of natural draft wet-cooling tower flow, heat and mass transfer. The moist air flow is described by the system of conservation laws along with additional equations. Moist air is assumed to be homogeneous mixture of dry air and water vapour. Liquid phase in the fill zone is described by the system of ordinary differential equations. Boundary value problem for the system of conservation laws is discretized in space using Kurganov-Tadmor central scheme and in time using strong stability preserving Runge-Kutta scheme. Initial value problems in the fill zone is solved by using standard fourth order Runge-Kutta scheme. The interaction between liquid water and moist air is done by source terms in governing equations.

  13. Performance of indices in cooling water system - a case study

    International Nuclear Information System (INIS)

    The corrosion/scale forming tendency of cooling water systems is generally predicted by measuring different saturation indices. For this purpose, indices like Langelier Saturation Index (LSI), Ryznar Stability Index (RSI) and Puckorius Scale Index (PSI) are generally used though many other indices have also been formulated for the same purpose. The main objective of using these indices is to adjust the cooling water chemistry to a non-corrosive condition. The Fast Breeder Test Reactor (FBTR) at Kalpakkam, Tamilnadu, India is a 40 MWt sodium cooled, mixed carbide (uranium and plutonium) fuelled nuclear test reactor. Cooling water system of FBTR comprises of service water system and condenser cooling water systems. Service water system forms the terminal heat sink for various process heat exchangers and steam water system auxiliary coolers. The condenser cooling water (CCW) system caters to main condenser, dump condenser, turbine oil cooler, generator air cooler and condensate cooler. Both the systems share a common induced draft-cooling tower, cooling water pit, corrosion monitoring set up, chlorinator and side stream filtration unit. In FBTR, cooling water system chemistry is maintained by dosing proprietary formulations comprising corrosion inhibitor, inorganic dispersant, bio-dispersant, chlorine activator and biocides along with chlorination. Water indices like LSI, RSI and PSI are being monitored for over a decade. These indices were formulated earlier to predict the corrosion/scaling tendency in the municipal drinking water systems which were not subjected to any kind of chemical treatment. In this paper, the usefulness and applicability of these indices for predicting the corrosion/scale forming tendency of chemically treated cooling water is discussed based on the obtained corrosion and scale data for the period from May 1998 to Dec 2007. (author)

  14. Water Towers, Water Tower & Standpipes FC of Water Utility Map of City of Ashland, WI, Published in 2007, 1:600 (1in=50ft) scale, City of Ashland.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Water Towers dataset, published at 1:600 (1in=50ft) scale, was produced all or in part from Other information as of 2007. It is described as 'Water Tower in a...

  15. Improvement to Air2Air Technology to Reduce Fresh-Water Evaporative Cooling Loss at Coal-Based Thermoelectric Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Ken Mortensen

    2011-12-31

    This program was undertaken to enhance the manufacturability, constructability, and cost of the Air2Air{TM} Water Conservation and Plume Abatement Cooling Tower, giving a validated cost basis and capability. Air2Air{TM} water conservation technology recovers a portion of the traditional cooling tower evaporate. The Condensing Module provides an air-to-air heat exchanger above the wet fill media, extracting the heat from the hot saturated moist air leaving in the cooling tower and condensing water. The rate of evaporate water recovery is typically 10% - 25% annually, depending on the cooling tower location (climate). This program improved the efficiency and cost of the Air2Air{TM} Water Conservation Cooling Tower capability, and led to the first commercial sale of the product, as described.

  16. Radar observation of snowfall from a natural-draft cooling tower plume

    International Nuclear Information System (INIS)

    One of the potential atmospheric effects of energy dissipation at large power parks is the mesoscale modification of the precipitation field. Meteorological conditions favorable for such an influence mainly correspond to naturally precipitating atmospheres and make the identification of the anthropogenic components difficult. In this paper, millimetric Doppler radar data are used in order to analyze the three-dimensional structure of snowfalls associated, in a perturbed environment, with a natural-draft cooling tower park. The plumes observed spread out in the atmospheric boundary layer with spread angles of 150--300 over a distance of more than 20 km. Their main characteristics compare favorably with Koenig's numerical simulation results

  17. Response Analysis of an RC Cooling Tower Under Seismic and Windstorm Effects

    OpenAIRE

    D. Makovi?ka

    2006-01-01

    The paper compares the RC structure of a cooling tower unit under seismic loads and under strong wind loads. The calculated values of the envelopes of the displacements and the internal forces due to seismic loading states are compared with the envelopes of the loading states due to the dead, operational and live loads, wind and temperature actions. The seismic effect takes into account the seismic area of ground motion 0.3 g and the ductility properties of a relatively rigid structure. The d...

  18. Measures for noise pollution abatement in existing cooling tower systems; Massnahmen zur Geraeuschminderung an bestehenden Kuehlturmanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Niessen, R. [Sulzer-Escher Wyss GmbH, Lindau (Germany)

    1998-09-01

    The operator`s order discussed by the paper was for planning and performance of backfitting measures for noise pollution abatement in an existing cooling tower system equipped with sound attenuation devices. Although the existing plant was operating in compliance with the legal noise emission limits, residents of neighbouring dwellings had been complaining about noise pollution. (orig./CB) [Deutsch] Die Aufgabe, eine nachtraegliche Massnahme zur Laermminderung an einer bestehenden, mit Schalldaempfern ausgeruesteten Anlage zu planen und durchzufuehren, wurde vom Betreiber einer Rueckkuehlanlage gestellt. Der vom Gesetzgeber definierte Grenzwert fuer den Nachtbetrieb wurde mit der bestehenden Anlage zwar erreicht, doch die Anwohner fuehlten eine Belaestigung durch den Anlagenbetrieb. (orig./GL)

  19. An experimental investigation on air-side performances of finned tube heat exchangers for indirect air-cooling tower

    Directory of Open Access Journals (Sweden)

    Du Xueping

    2014-01-01

    Full Text Available A tremendous quantity of water can be saved if the air cooling system is used, comparing with the ordinary water-cooling technology. In this study, two kinds of finned tube heat exchangers in an indirect air-cooling tower are experimentally studied, which are a plain finned oval-tube heat exchanger and a wavy-finned flat-tube heat exchanger in a cross flow of air. Four different air inlet angles (90°, 60 °, 45°, and 30° are tested separately to obtain the heat transfer and resistance performance. Then the air-side experimental correlations of the Nusselt number and friction factor are acquired. The comprehensive heat transfer performances for two finned tube heat exchangers under four air inlet angles are compared. For the plain finned oval-tube heat exchanger, the vertical angle (90° has the worst performance while 45° and 30° has the best performance at small ReDc and at large ReDc, respectively. For the wavy-finned flat-tube heat exchanger, the worst performance occurred at 60°, while the best performance occurred at 45° and 90° at small ReDc and at large ReDc, respectively. From the comparative results, it can be found that the air inlet angle has completely different effects on the comprehensive heat transfer performance for the heat exchangers with different structures.

  20. Epidemic dangers on account of the operation of cooling towers and the heating up of rivers

    International Nuclear Information System (INIS)

    For some time fear has been growing amongst the population that through a temperature increase in waters as a result of cooling water discharges there may be an increase in pathogenic agents, especially in typhoid bacteria. After the conclusions brought about by personal, extensive examinations in still and running waters burdened with cooling water as well as by a test plant supplied with cooling water, neither an increase in the colony numerical values exceeding 4 digit numbers nor an increase in Salmonellae or the typhoid bacteria belonging to this group, could be determined. (orig.)

  1. Condenser cooling water quality at Kaiga

    International Nuclear Information System (INIS)

    Once-through circulation of river water is envisaged in Kaiga for cooling the condenser and other related equipment. Water drawn from Kali river will be used for this purpose. After cooling the condenser, the water is let into the river through the outfall system. The materials used in the cooling water system consist mainly of SS 316 and carbon steel. Chlorination is the treatment proposed to the cooling water. The cooling water quality is found to be satisfactory. (author). 2 refs

  2. Optimization of low-potential complex of NPP with mixed closed-cycle water cooling system

    International Nuclear Information System (INIS)

    The results of optimal design calculation of a circulation water cooling system in an NPP, whose power is stepped up from 2000 to 4000 MW are presented. It is assumed that the NPP comprises power plant units with a WWER-1000 reactor and saturated 6.5 MPa steam turbine of 1000 MW capacity. For two climatic zones of the European part of the USSR - the Center and the South - the possibility of raising the thermal load of the existing reservoir-cooler (R-C) system or using instead a combination of R-C plus cooling tower system is considered. It is shown that when the combination of R-C and cooling towers is used the low-potential complex parameters correspond to those of the most expensive part of the combined cooling system - the cooling towers

  3. Cooling tower performance improvements for a cycling PC-fired unit

    International Nuclear Information System (INIS)

    The inevitable deregulation of the electric utility industry has caused many electric utility companies to look closely at their existing assets and predict what role these units will play in the future. Reducing a unit's production cost is the best way to prepare for the deregulated market but this benefit often comes with an associated capital expenditure. Spending capital dollars today can pose a quandary for an investor-owned utility committed to maintaining low consumer rates. The dilemma is: How does a utility improve its competitiveness position today while ensuring that the shareholders are getting a fair return on their investment when any fuel savings are passed through to the consumer? Illinois Power (IP) has been aggressively looking to improve their current competitive position while facing the current regulatory challenges. Studies have been commissioned to identify the most attractive cost reduction opportunities available. One study identified that improving the performance of the Unit 6 cooling tower at the Havana Station would be a very economically attractive option. This paper addresses the economics of refurbishing a cooling tower for a cycling pulverized-coal (PC) unit to provide a competitive advantage leading into the deregulated electricity market

  4. Auxiliary equipment cooling water system for nuclear power plant

    International Nuclear Information System (INIS)

    The present invention concerns an auxiliary equipment cooling water system for a nuclear power plant, which reduces after-heat during operation, increases heat efficiency of the plant, improves the economy and mitigates circumstantial problems. That is, condensates condensed in a main condensator are introduced to a condensate desalting tower by a pump and then cleaned. Cleaned condensates are bypassed and introduced to an auxiliary equipment heat exchanger used for the time during operation and cooled. Cooled condensates are introduced to a feedwater heater by a highly pressurized condensate pump connected to the downstream of the condensate desalting tower and then heated. They are supplied into a reactor pressure vessel as coolants. That is, heat removed by using condensates, instead of sea water, which are condensed in the main condensator is recovered to a feedwater system of the nuclear reactor. As a result, a heat efficiency of the plant can be increased by 0.5 to 0.6%. With such procedures, possibility of releasing radioactivity into the sea water due to leakage of the cooling water of the equipments during operation is decreased. (I.S.)

  5. Lawrence Livermore National Laboratory (LLNL) Experimental Test Site (Site 300) Salinity Evaluation and Minimization Plan for Cooling Towers and Mechanical Equipment Discharges

    Energy Technology Data Exchange (ETDEWEB)

    Daily III, W D

    2010-02-24

    This document was created to comply with the Central Valley Regional Water Quality Control Board (CVRWQCB) Waste Discharge Requirement (Order No. 98-148). This order established new requirements to assess the effect of and effort required to reduce salts in process water discharged to the subsurface. This includes the review of technical, operational, and management options available to reduce total dissolved solids (TDS) concentrations in cooling tower and mechanical equipment water discharges at Lawrence Livermore National Laboratory's (LLNL's) Experimental Test Site (Site 300) facility. It was observed that for the six cooling towers currently in operation, the total volume of groundwater used as make up water is about 27 gallons per minute and the discharge to the subsurface via percolation pits is 13 gallons per minute. The extracted groundwater has a TDS concentration of 700 mg/L. The cooling tower discharge concentrations range from 700 to 1,400 mg/L. There is also a small volume of mechanical equipment effluent being discharged to percolation pits, with a TDS range from 400 to 3,300 mg/L. The cooling towers and mechanical equipment are maintained and operated in a satisfactory manner. No major leaks were identified. Currently, there are no re-use options being employed. Several approaches known to reduce the blow down flow rate and/or TDS concentration being discharged to the percolation pits and septic systems were reviewed for technical feasibility and cost efficiency. These options range from efforts as simple as eliminating leaks to implementing advanced and innovative treatment methods. The various options considered, and their anticipated effect on water consumption, discharge volumes, and reduced concentrations are listed and compared in this report. Based on the assessment, it was recommended that there is enough variability in equipment usage, chemistry, flow rate, and discharge configurations that each discharge location at Site 300 should be considered separately when deciding on an approach for reducing the salt discharge to the subsurface. The smaller units may justify moderate changes to equipment, and may benefit from increased cleaning frequencies, more accurate and suitable chemical treatment, and sources of make up water and discharge re-use. The larger cooling towers would be more suitable for automated systems where they don't already exist, re-circulation and treatment of blow down water, and enhanced chemical dosing strategies. It may be more technically feasible and cost efficient for the smaller cooling towers to be replaced by closed loop dry coolers or hybrid towers. There are several potential steps that could be taken at each location to reduce the TDS concentration and/or water use. These include: sump water filtration, minimization of drift, accurate chemical dosing, and use of scale and corrosion coupons for chemical calibration. The implementation of some of these options could be achieved by a step-wise approach taken at two representative facilities. Once viable prototype systems have been proven in the field, systematic implementation should proceed for the remaining systems, with cost, desired reduction, and general feasibility taken into consideration for such systems.

  6. Lawrence Livermore National Laboratory (LLNL) Experimental Test Site (Site 300) Salinity Evaluation and Minimization Plan for Cooling Towers and Mechanical Equipment Discharges

    International Nuclear Information System (INIS)

    This document was created to comply with the Central Valley Regional Water Quality Control Board (CVRWQCB) Waste Discharge Requirement (Order No. 98-148). This order established new requirements to assess the effect of and effort required to reduce salts in process water discharged to the subsurface. This includes the review of technical, operational, and management options available to reduce total dissolved solids (TDS) concentrations in cooling tower and mechanical equipment water discharges at Lawrence Livermore National Laboratory's (LLNL's) Experimental Test Site (Site 300) facility. It was observed that for the six cooling towers currently in operation, the total volume of groundwater used as make up water is about 27 gallons per minute and the discharge to the subsurface via percolation pits is 13 gallons per minute. The extracted groundwater has a TDS concentration of 700 mg/L. The cooling tower discharge concentrations range from 700 to 1,400 mg/L. There is also a small volume of mechanical equipment effluent being discharged to percolation pits, with a TDS range from 400 to 3,300 mg/L. The cooling towers and mechanical equipment are maintained and operated in a satisfactory manner. No major leaks were identified. Currently, there are no re-use options being employed. Several approaches known to reduce the blow down flow rate and/or TDS concentration being discharged to the percolation pits and septic systems were reviewed for technical feasibility and cost efficiency. These options range from efforts as simple as eliminating leaks to implementing advanced and innovative treatment methods. The various options considered, and their anticipated effect on water consumption, discharge volumes, and reduced concentrations are listed and compared in this report. Based on the assessment, it was recommended that there is enough variability in equipment usage, chemistry, flow rate, and discharge configurations that each discharge location at Site 300 should be considered separately when deciding on an approach for reducing the salt discharge to the subsurface. The smaller units may justify moderate changes to equipment, and may benefit from increased cleaning frequencies, more accurate and suitable chemical treatment, and sources of make up water and discharge re-use. The larger cooling towers would be more suitable for automated systems where they don't already exist, re-circulation and treatment of blow down water, and enhanced chemical dosing strategies. It may be more technically feasible and cost efficient for the smaller cooling towers to be replaced by closed loop dry coolers or hybrid towers. There are several potential steps that could be taken at each location to reduce the TDS concentration and/or water use. These include: sump water filtration, minimization of drift, accurate chemical dosing, and use of scale and corrosion coupons for chemical calibration. The implementation of some of these options could be achieved by a step-wise approach taken at two representative facilities. Once viable prototype systems have been proven in the field, systematic implementation should proceed for the remaining systems, with cost, desired reduction, and general feasibility taken into consideration for such systems.

  7. Fill fouling experiences on both mechanical and natural draft towers

    International Nuclear Information System (INIS)

    Fouling of the film fill in cooling towers is becoming an increasingly serious problem in the Utility Industry. This paper discusses Florida Power Corporation's experience with fouling of film type fill in two mechanical draft and two natural draft towers. The two mechanical draft towers were placed in service as helper towers at the Anclote Plant in 1981. The two natural draft towers went into service at the Crystal River North Site in 1982 and 1984 for closed cycle cooling. All the towers are on salt water systems

  8. Chlorination and dechlorination of nuclear reactor cooling water

    International Nuclear Information System (INIS)

    Effects from chlorination and dechlorination of Savannah River water were studied during the development of biofouling countermeasures for a proposed cooling tower system required for thermal mitigation of nuclear reactor cooling water effluent. Testing was conducted to assess chlorine demand and dissipation rates as well as the environmental acceptability of using sodium sulfite as a dechlorinating agent. Chlorine demand varied significantly, but in an unpredictable manner during seven seasonal sampling dates. A chlorine dosage of 3-5 mg/l was generally adequate to provide a free chlorine residual of 1 mg/l. Static 48-h bioassays with bluegill showed no acute toxicity for chlorinated/dechlorinated cooling water containing up to 64 times the calculated stoichiometric concentration of sodium sulfite required for dechlorination. Experiments measuring the depletion of dissolved oxygen and flow-through (96-h) bioassays with bluegill and largemouth bass further substantiated the environmental acceptability of using sodium sulfite as a dechlorinating agent. (author)

  9. Development of wet-bulb-temperatures in Germany with special regard to conventional thermal power plants using wet cooling towers

    Energy Technology Data Exchange (ETDEWEB)

    Aich, Valentin; Paeth, Heiko [Univ. of Wuerzburg (Germany). Inst. of Geography; Strauch, Ulrike [European Institute for Energy Research, Karlsruhe (Germany); Sieck, Kevin; Jacob, Daniela [Max-Planck-Institute for Meteorology, Hamburg (Germany); Leyens, Dirk [EnBW Energie Baden-Wuerttemberg AG, Karlsruhe (Germany)

    2011-12-15

    Wet-bulb-temperature (WBT) defines the cooling distance of cooling water in wet cooling towers (or wet honeycomb radiators) at water-cooled power plants. Thus, the development of WBT in the 21{sup st} century under different scenarios of future climate change is highly relevant for the electricity production sector and is examined in this study for Germany. We use high-resolution simulated data from the regional climate model REMO. As WBT is no direct model output, it is calculated using dry-bulb-temperature (DBT), relative humidity and surface air pressure using two alternative methods. The iterative method provides better results for validation. The computed WBT is quite close to the observations. It reveals a statistically significant exponential increase until 2100 ranging from 1.6 C to 2.4 C in the B1 scenario and from 2.6 C to 3.4 C in the A2-scenario. Furthermore the study indicates that changes of the DBT will be the decisive factor for the WBT-increase in the 21{sup st} century. Significant differences in the increase of extreme heat events between a region in northern and one in southwestern Germany are highlighted by a threshold analysis. The increase of hourly extreme values in southwestern Germany is about 30% higher than in the north. A detected west-east gradient is probably related to the North Atlantic Oscillation and a general increase in westerly situations over Germany. The discrepancies between B1 and A2 scenario are striking and highlight the impact of different levels of global greenhouse gas emissions on regional climate. (orig.)

  10. Recirculating cooling water solute depletion models

    International Nuclear Information System (INIS)

    Chromates have been used for years to inhibit copper corrosion in the plant Recirculating Cooling Water (RCW) system. However, chromates have become an environmental problem in recent years both in the chromate removal plant (X-616) operation and from cooling tower drift. In response to this concern, PORTS is replacing chromates with Betz Dianodic II, a combination of phosphates, BZT, and a dispersant. This changeover started with the X-326 system in 1989. In order to control chemical concentrations in X-326 and in systems linked to it, we needed to be able to predict solute concentrations in advance of the changeover. Failure to predict and control these concentrations can result in wasted chemicals, equipment fouling, or increased corrosion. Consequently, Systems Analysis developed two solute concentration models. The first simulation represents the X-326 RCW system by itself; and models the depletion of a solute once the feed has stopped. The second simulation represents the X-326, X-330, and the X-333 systems linked together by blowdown. This second simulation represents the concentration of a solute in all three systems simultaneously. 4 figs

  11. Effect of water treatment on the comparative costs of evaporative and dry cooled power plants

    International Nuclear Information System (INIS)

    The report presents the results of a study on the relative cost of energy from a nominal 1000 Mwe nuclear steam electric generating plant using either dry or evaporative cooling at four sites in the United States: Rochester, New York; Sheridan, Wyoming; Gallup, New Mexico and Dallas, Texas. Previous studies have shown that because of lower efficiencies the total annual evaluated costs for dry cooling systems exceeds the total annual evaluated costs of evaporative cooling systems, not including the cost of water. The cost of water comprises the cost of supplying the makeup water, the cost of treatment of the makeup and/or the circulating water in the tower, and the cost of treatment and disposal of the blowdown in an environmentally acceptable manner. The purpose of the study is to show the effect of water costs on the comparative costs of dry and evaporative cooled towers

  12. Cooling-water effluents into polluted waters

    International Nuclear Information System (INIS)

    The knowledge how cooling water effluents influence the waters has been extensively deepened during the past years. This applies mainly to heavily loaded waters which are subjected to many scientific investigations. Special attention is paid to the quality data for waters, which have been established by the water supply authorities and the power plant corporations. Together with model calculations, they do not only extend the conventional random test measurements by continuous recordings, they do however also show, how problematic these measurements unfortunately were, on which the statements of the water quality economy was based until today. With the discharge of cooling water into a water, four parameters with more or less extensive influence on the water quality are effective: lead-in of heat, oxygen content, entry of chemicals, vaporization. Their magnitude however is different, depending on the type of cooling of the concerned power plant. It also would be wrong to consider their effects each one isolated by itself, as it was done for a long time. Moreover they can only be judged and valuated by considering the close mutual relation. Wide ranged knowledge of the mentioned connections makes it possible today to harmonize the requirements for the protection of waters with the interests of the public energy supply and to obtain adaptable solutions. (orig.)

  13. Cost and performance optimization of natural draft dry cooling towers using genetic algorithm. Paper no. IGEC-1-002

    International Nuclear Information System (INIS)

    In this paper the cost - performance optimization of natural draft dry cooling towers with specific kind of heat exchangers, known as Forgo T60 has been investigated. These cooling towers are used in combined and steam cycle power plants. The optimization has been done using genetic algorithm. The objective function has two parts, which are minimizing the cost and maximizing the performance. In the first part the geometrical and operating parameters are defined and for the next part the performance of the designed tower for different ambient temperatures during a year is calculated considering the characteristic curve of the turbine. The applied genetic algorithm has been tuned up using the data of some working power cycles. The results show it is possible to find an optimum for all design parameters; however it is very dependent on how exact the cost analysis is. (author)

  14. Cost and performance optimization of natural draft dry cooling towers using genetic algorithm. Paper no. IGEC-1-002

    Energy Technology Data Exchange (ETDEWEB)

    Shokuhmand, H.; Ghaempanah, B. [Univ. of Tehran, Dept. of Mechanical Engineering, Tehran (Iran, Islamic Republic of)]. E-mail: hshokouh@me.ut.ac.ir; bghaempanah@me.ut.ac.ir

    2005-07-01

    In this paper the cost - performance optimization of natural draft dry cooling towers with specific kind of heat exchangers, known as Forgo T60 has been investigated. These cooling towers are used in combined and steam cycle power plants. The optimization has been done using genetic algorithm. The objective function has two parts, which are minimizing the cost and maximizing the performance. In the first part the geometrical and operating parameters are defined and for the next part the performance of the designed tower for different ambient temperatures during a year is calculated considering the characteristic curve of the turbine. The applied genetic algorithm has been tuned up using the data of some working power cycles. The results show it is possible to find an optimum for all design parameters; however it is very dependent on how exact the cost analysis is. (author)

  15. Dry cooling towers for GT-MHR - HTR2008-58182

    International Nuclear Information System (INIS)

    Due to problems with the availability and the price of water, and the concerns relating to adverse environmental effects of wet cooling systems, the need for water conserving cooling systems has been increasing. Presently, dry cooling accounts for over 30, 000 MWe of capacity in more than 30 countries. GT-MHR is specially suited for use of dry cooling due to 1) high efficiency, 2) high heat rejection temperatures and 3) large temperature difference between the turbine inlet and heat rejection temperatures. Higher efficiency means the amount of energy rejected to the cooling per MWe is less. The majority of heat is rejected in pre-cooler and inter-cooler at helium temperature of more than 100 deg. C. This results in higher temperature difference for heat rejection. Also due to large temperature difference between the turbine inlet and heat rejection temperatures, changes in ambient temperature have a smaller effect on overall thermal efficiency. Preliminary evaluation shows that pure dry cooling is economical for GT-MHR for water cost of more than 0.8$/m3 and power cost of 3.5 c/kWh. A combination of dry and wet cooling can reduce large percentage of the water use without affecting the efficiency. (authors)

  16. Response Analysis of an RC Cooling Tower Under Seismic and Windstorm Effects

    Directory of Open Access Journals (Sweden)

    D. Makovi?ka

    2006-01-01

    Full Text Available The paper compares the RC structure of a cooling tower unit under seismic loads and under strong wind loads. The calculated values of the envelopes of the displacements and the internal forces due to seismic loading states are compared with the envelopes of the loading states due to the dead, operational and live loads, wind and temperature actions. The seismic effect takes into account the seismic area of ground motion 0.3 g and the ductility properties of a relatively rigid structure. The ductility is assessed as the reduction in seismic load. In this case the actions of wind pressure are higher than the seismicity effect under ductility correction. The seismic effects, taking into account the ductility properties of the structure, are lower than the actions of the wind pressure. The other static loads, especially temperature action due to the environment and surface insulation are very important for the design of the structure. 

  17. Calculation of air gap between the protective screen and the shell of reinforced concrete cooling tower

    Directory of Open Access Journals (Sweden)

    Svetlana Vyacheslavovna Belyaeva

    2013-04-01

    Full Text Available Article is devoted to a question of maintenance of effective protection of the cooling tower shell, using the screen with ventilated air gap. The purpose of the work is to determine the optimal parameters of the air gap by the calculation of heat and humidity and aerodynamic mode. In this article, there are calculations showing influence of temperature conditions and thickness of a ventilated air gap on warm, humidity and aerodynamic modes of its work. The thickness of the 140-160 mm of an air gap, provided on the heating air inlet gap, provides the ability to assimilate air moisture throughout the layer and to remove it in an atmosphere which prevents moisture condensation on cold surfaces of the concrete shell.

  18. Effect of cooling tower vapours on agriculture in the environment of power plants

    International Nuclear Information System (INIS)

    The effect of cooling tower vapours according to investigations made so far are mainly noticeable regarding solar radiation, and this is practically merely in the immediate neighbourhood of the power plant. The effective influence on photosynthesis should be hardly detectable even in this limited area around the power plant. The effect on the temperature is minimum, the influence on the relative moisture is so small that it lies within the margin of error of measuring, with the exception of the few cases in which the vapours are pressed down to the ground. One need not reckon with an increased fungoid growth and bad drying conditions. Rainfall could be additionally increased if the weather situation is likely to rain or if it is raining anyway. Regarding fog frequency, one may assume that there might be a certain increase in fog. So far no cases are known in which fog would occur where there is no general tendency for fog formation. (orig.)

  19. Heat and mass transfer in cooling towers - comparison of 1D numerical simulation with the technical approach.

    Czech Academy of Sciences Publication Activity Database

    Zuniga-Gonzalez, Israel; Maršík, František

    Vol. 2. Tokyo : Hosei University, 2005 - (Mizuki, S.; Setoguchi, T.), s. 505-510 [ISAIF /7./ : International Symposium on Experimental and Computational Aerothermodynamics of Internal Flows /7./. Tokyo (JP), 11.09.2005-15.09.2005] R&D Projects: GA ?R(CZ) GA101/05/2536; GA MŠk 1P05ME726 Institutional research plan: CEZ:AV0Z20760514 Keywords : cooling tower * evaporative cooling * heat transfer Subject RIV: BK - Fluid Dynamics

  20. Concerning calculation and construction of the natural-draft cooling tower of the Goesgen-Daeniken nuclear power station

    International Nuclear Information System (INIS)

    The principal design criteria and constructional details of the 150 m high reinforced concrete, natural-draft cooling tower and its foundations are described, presenting an outline and the results of static and dynamic calculations and laboratory model tests. The article does not include the functional and operational aspects of the design. (S.R.)

  1. Cooling Tower Optimization A Simple Way to Generate Green Megawatts and to Increase the Efficiency of a Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Strohmer, F.

    2014-07-01

    The profitability of nuclear power plants is worldwide challenged by low electricity prices. One hand low cost shale gas is offering a low price electricity production , other hand additional taxes on fuel are reducing the operating income of nuclear power stations. The optimization of cooling towers can help to increase the efficiency and profit of a nuclear power plant. (Author)

  2. Cooling Tower Optimization A Simple Way to Generate Green Megawatts and to Increase the Efficiency of a Power Plant

    International Nuclear Information System (INIS)

    The profitability of nuclear power plants is worldwide challenged by low electricity prices. One hand low cost shale gas is offering a low price electricity production , other hand additional taxes on fuel are reducing the operating income of nuclear power stations. The optimization of cooling towers can help to increase the efficiency and profit of a nuclear power plant. (Author)

  3. Chalk point cooling tower project. Progress report No. 1, FY 1977, July 1, 1976--February 28, 1977

    International Nuclear Information System (INIS)

    Progress is reported on equipment documentation, meteorological data acquisition and reduction, data archiving format preparation, and data analyses for the Chalk Point fossil-fuel power plant cooling tower environmental effects. A description of the work performed in these areas together with recommendations for future work is presented in this report

  4. Horizontal cooling towers: riverine ecosystem services and the fate of thermoelectric heat in the contemporary Northeast US

    International Nuclear Information System (INIS)

    The electricity sector is dependent on rivers to provide ecosystem services that help regulate excess heat, either through provision of water for evaporative cooling or by conveying, diluting and attenuating waste heat inputs. Reliance on these ecosystem services alters flow and temperature regimes, which impact fish habitat and other aquatic ecosystem services. We demonstrate the contemporary (2000–2010) dependence of the electricity sector on riverine ecosystem services and associated aquatic impacts in the Northeast US, a region with a high density of thermoelectric power plants. We quantify these dynamics using a spatially distributed hydrology and water temperature model (the framework for aquatic modeling in the Earth system), coupled with the thermoelectric power and thermal pollution model. We find that 28.4% of thermoelectric heat production is transferred to rivers, whereas 25.9% is directed to vertical cooling towers. Regionally, only 11.3% of heat transferred to rivers is dissipated to the atmosphere and the rest is delivered to coasts, in part due to the distribution of power plants within the river system. Impacts to the flow regime are minimal, while impacts to the thermal regime include increased river lengths of unsuitable habitats for fish with maximum thermal tolerances of 24.0, 29.0, and 34.0?° C in segments downstream of plants by 0.6%, 9.8%, and 53.9%, respectively. Our analysis highlights the interactions among electricity production, cooling technologies, aquatic impacts, and ecosystem services, and can be used to assess the full costs and tradeoffs of electricity production at regional scales. (letter)

  5. 18 CFR 420.44 - Cooling water.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Cooling water. 420.44 Section 420.44 Conservation of Power and Water Resources DELAWARE RIVER BASIN COMMISSION ADMINISTRATIVE MANUAL BASIN REGULATIONS-WATER SUPPLY CHARGES Charges; Exemptions § 420.44 Cooling water. Water...

  6. Cooling water for Koeberg nuclear power station

    International Nuclear Information System (INIS)

    A major water system of the nuclear power plant under construction at Koeberg is the cooling water system which provides the cooling to condense the steam exhausted from the turbines. Seawater will be used for this system and an intake basin has been designed to supply the condenser cooling water. The process of refining the layout is described

  7. Hydraulic design of a low-specific speed Francis runner for a hydraulic cooling tower

    International Nuclear Information System (INIS)

    The air blower in a cooling tower is normally driven by an electromotor, and the electric energy consumed by the electromotor is tremendous. The remaining energy at the outlet of the cooling cycle is considerable. This energy can be utilized to drive a hydraulic turbine and consequently to rotate the air blower. The purpose of this project is to recycle energy, lower energy consumption and reduce pollutant discharge. Firstly, a two-order polynomial is proposed to describe the blade setting angle distribution law along the meridional streamline in the streamline equation. The runner is designed by the point-to-point integration method with a specific blade setting angle distribution. Three different ultra-low-specificspeed Francis runners with different wrap angles are obtained in this method. Secondly, based on CFD numerical simulations, the effects of blade setting angle distribution on pressure coefficient distribution and relative efficiency have been analyzed. Finally, blade angles of inlet and outlet and control coefficients of blade setting angle distribution law are optimal variables, efficiency and minimum pressure are objective functions, adopting NSGA-II algorithm, a multi-objective optimization for ultra-low-specific speed Francis runner is carried out. The obtained results show that the optimal runner has higher efficiency and better cavitation performance.

  8. Hydraulic design of a low-specific speed Francis runner for a hydraulic cooling tower

    Science.gov (United States)

    Ruan, H.; Luo, X. Q.; Liao, W. L.; Zhao, Y. P.

    2012-11-01

    The air blower in a cooling tower is normally driven by an electromotor, and the electric energy consumed by the electromotor is tremendous. The remaining energy at the outlet of the cooling cycle is considerable. This energy can be utilized to drive a hydraulic turbine and consequently to rotate the air blower. The purpose of this project is to recycle energy, lower energy consumption and reduce pollutant discharge. Firstly, a two-order polynomial is proposed to describe the blade setting angle distribution law along the meridional streamline in the streamline equation. The runner is designed by the point-to-point integration method with a specific blade setting angle distribution. Three different ultra-low-specificspeed Francis runners with different wrap angles are obtained in this method. Secondly, based on CFD numerical simulations, the effects of blade setting angle distribution on pressure coefficient distribution and relative efficiency have been analyzed. Finally, blade angles of inlet and outlet and control coefficients of blade setting angle distribution law are optimal variables, efficiency and minimum pressure are objective functions, adopting NSGA-II algorithm, a multi-objective optimization for ultra-low-specific speed Francis runner is carried out. The obtained results show that the optimal runner has higher efficiency and better cavitation performance.

  9. Driving gear for cooling towers - design, noise abatement, maintenance; Antriebssysteme fuer Kuehltuerme - Auslegung, Schallschutz, Instandhaltung

    Energy Technology Data Exchange (ETDEWEB)

    Niestegge, J.; Plesser, J. [Flender (A.F.) und Co., Bocholt (Germany)

    1998-09-01

    Any optimal design of a cooling tower driving gear requires as precise as possible information on the operating conditions in practice. In addition, design engineers use verified data warranting reliable operation of the driving gears. From those data together with information on the specific operating environment and position in the cooling system, engineers derive the application-specific design data for the driving mechanisms, such as for instance special protective coatings, or specific bearing geometries. Other requirements considered include aspects of maintenance and noise abatement. (orig./CB) [Deutsch] Eine optimale Auslegung von Kuehlturmantrieben bedingt eine moeglichst exakte Angabe der Betriebsbedingungen. Darueber hinaus fliessen in die Auslegung Erfahrungswerte ein, die einen stoerungsfreien Betrieb der Getriebe gewaehrleisten. Mit diesen Daten und unter Beruecksichtigung des speziellen Aufstellortes ergibt sich ein kuehlturmspezifisches Getriebe, das z.B. durch den vergroesserten Lagerabstand oder durch die Sonderlackierung den Anforderungen im Kuehlturmbau in groesstmoeglicher Weise gerecht wird. Massgaben hinsichtlich der Wartungsfreundlichkeit und des Geraeuschverhaltens werden bei der Auslegung ebenfalls beruecksichtigt. (orig.)

  10. Design of, and results of investigations into, indirect cooling for 1200 MW pressurised water reactor power stations

    International Nuclear Information System (INIS)

    Indirect dry cooling for extreme air temperature variations from -160C to +420C has been investigated for a site in an earthquake zone which is short of water. In addition, high wind velocities and storms occur at this site. The investigation was based on four similar dry cooling towers operating in parallel,in order to keep broadly within the range of proven ratings for dry cooling towers using this type of cooling system. The results of the optimised design data and of wind tunnel and laboratory investigations are described in detail together with literature studies under prescribed conditions. (orig.)

  11. Unusual Decommissioning of Contaminated Facilities at the Savannah River Site - The Demolition of Cooling Towers 285-H and 285-F

    International Nuclear Information System (INIS)

    Savannah River Site is an 800-square kilometer (310-square mile) U.S. Department of Energy (DOE) industrial facility located in Aiken, Allendale, and Barnwell Counties in South Carolina. The site is dedicated to environmental cleanup, developing and deploying technologies to support the cleanup mission, processing and storing nuclear materials, and supporting national security missions. The current focus in environmental management is on the cleanup of legacy materials, facilities and wastes left from the Cold War. In 2002 the DOE initiated actions to expedite cleanup focusing on significant risk reduction coupled with reducing costs. SRS published the Savannah River Site Environmental Management Integrated Deactivation and Decommissioning Plan in 2003 which addressed the final disposition and physical end state of all 1,013 Environmental Management facilities on site by the year 2025. Included in this list of facilities are reactors, fabrication facilities, process facilities and the support facilities that were required during the past 50 years. By the end of FY06, over 200 facilities had been decommissioned. This paper describes the demolition of two facilities, cooling towers 285-H and 285-F that were associated with the operation of the process canyons. Because of the circumstances surrounding these decommissions, unique and unusual techniques were safely employed to demolish and remove the cooling towers. Both 285-H and 285-F were safely felled by pulling the columns remotely to weaken the internal portion of the structure so it would collapse inwards into the basin. Cooling tower 285-H fell in less than 1 second after approximately two-thirds of the columns had been broken. See Figure 3 for a photo of 285-H after its collapse. 285-F, which was larger than 285-H, fell in three sections, two cells at a time. Once the towers were felled conventional demolition equipment was used to segregate and remove the debris. All protective measures used to protect surrounding equipment and structures were successful and the basins were cleaned out and returned to service in less than two weeks. The demolition of both cooling towers 285- H and 285-F was completed safely and timely using unconventional means to fell the towers due to structural degradation, height, limited access, radiological and asbestos hazards, and a requirement to protect equipment on all sides of the facility as well as preservation of the basins. During felling operations personnel were required to stay outside the fall zone equivalent to a distance of 150% of the height of the towers. Remote operations outside the fall zone required a tracked vehicle to pull cables attached to the columns in a predetermined sequence so as to fell the tower straight down into the basin. Once the towers fell traditional demolition equipment segregated and removed the waste. Wooden cooling towers of this vintage present a difficult challenge to traditional demolition techniques. Because of the height and potential instability of these types of facilities, considerable effort is placed on reducing the potential energy to a point where heavy equipment can reach safely without endangering the operators. The column-pulling technique chosen for both 285-H and 285-F cooling towers proved to be a safe and efficient method for demolition of these types of facilities

  12. Measuring environmental pollution and the effect of cooling towers in the 220 kV substation of the V-1 nuclear power plant at Jaslovske Bohunice

    International Nuclear Information System (INIS)

    Two methods are described used to study the level of environmental pollution and the effect of cooling towers on the insulation of the 220 kV substation of the nuclear power plant. The use of the IMICONT apparatus is based on a change in the conductivity of an absorption solution following the passage of air. The change in conductivity is proportional to air pollution. The EGU method is based on measuring the conductivity of fallout trapped in a constant amount of water. The results of measurement show good agreement for the two measuring methods. (J.C.)

  13. Biocide efficiency against Legionellae and amoebae in cooling towers - the necessity to control the risk of Legionnaires' disease

    Energy Technology Data Exchange (ETDEWEB)

    Guhl, W.; Hater, W.; Stumpe, S. [Henkel KGaA, Duesseldorf (Germany)

    2007-08-15

    Legionella, known to be the causative agent of Legionnaires' disease, is a wide-spread bacteria occurring naturally in water. Favorable growing conditions in man-made systems can lead to massive growth and thus to a considerable risk for human beings. Evaporative cooling towers provide good living conditions due to their operational conditions. As a consequence, the growth of Legionella in these systems has to be controlled. Amongst other measures biocides are dosed to control the growth of the microbiological population and thus the possible risk of an infection by Legionellae. However, Legionella preferably lives in biofilms and/or amoebae, which strongly shelter this microbe. Furthermore, amoebae by themselves can be harmful to humans as well. Therefore, a biocide treatment should control Legionella (planktonic in water and in biofilms/amoebae) as well as the amoebae. This paper shows that an adapted biocide treatment can increase the efficiency of a biocide against Legionellae and amoebae und therefore minimize the risk of an infection by Legionella. (orig.)

  14. Supporting behaviour of natural-draft cooling towers under special consideration of mining influences

    International Nuclear Information System (INIS)

    Axially symmetrical cooling shells with their supports and foundation elements exhibit a very favorable supporting behavior with respect to mining influences, resisting them demage-free without or with little additional constructional effort. This paper primarily deals with cooling shells including their supports and foundations. Water supply and distribution, cascading system, and water basin are admittedly unseparable components of wet coolers, but their safety problems with respect to damage due to mining operations lie in the range of classical methods of solution. (orig./TK)

  15. Optimized performance of surface protection systems on natural draught cooling towers with flue gas discharge; Optimierte Leistungsfaehigkeit von Oberflaechenschutzsystemen in Naturzugkuehltuermen mit Abgaseinleitung

    Energy Technology Data Exchange (ETDEWEB)

    Engelfried, R. [oe.b.u.v. Sachverstaendiger fuer Beschichtungen im Bauwesen, Betoninstandsetzung, Herdecke (Germany); Bandt, N. [RWE Power AG, Technische Dienste Instandhaltungsprojekte, Grevenbroich (Germany); Titze, B. [Vattenfall Europe Generation AG und Co. KG, Cottbus (Germany)

    2006-07-01

    Epoxy coatings were applied on the inside shell surface of natural draught cooling towers in the 80s and 90s to protect the surfaces against the acid impact of vapour/flue gas condensate after these cooling towers were retrofitted for discharge of flue gas downstream of FGD. Currently proved perceptions concerning the behaviour of modern coating systems show that they have a significantly increased resistance against operational impacts and environmental influences than the epoxy systems that were used in the 90s. This results in a better performance and higher durability expectations of the protection systems especially on new but also on retrofitted cooling towers. (orig.)

  16. 40 CFR 749.68 - Hexavalent chromium-based water treatment chemicals in cooling systems.

    Science.gov (United States)

    2010-07-01

    ... claim of confidentiality only to the extent permitted by section 14 of TSCA and 40 CFR part 2, subpart B... dedicated exlusively to and are an integral part of heating, ventilation, and air conditioning or... chemicals, where the mixture can be used to treat water. (12) Industrial cooling tower means any...

  17. Effect of supporting structure stiffness on the drive train assembly of an induced draft cooling tower under seismic effects

    International Nuclear Information System (INIS)

    In a nuclear power project an induced draft cooling tower, as a safety-related structure and part of the main cooling system, has to perform satisfactorily under designated seismic effects. While the structural elements can be designed by conventional methods to ensure adequate safety, the seismic qualification of the mechanical components poses a challenge. The paper describes a methodology adopted for the seismic qualification of a typical Drive Train Assembly for the axial flow fan of an induced draft cooling tower, to ensure the structural integrity and functional operability of the assembly during Operating Base Earthquake and Safe Shutdown Earthquake conditions. This is achieved by performing a detailed finite element analysis of the rotating equipment assembly consisting of the electric motor, gear box and fan along with the drive shaft between the motor and the gear box. The various components are modeled using beam elements, plate elements and spring elements to idealize the flexible connections and supports. The floor response spectra derived from a dynamic analysis of the overall structure under stipulated seismic acceleration spectra are the main excitation inputs into the system. The results validate the adequacy of gaps for movement and the strengths of the couplings and bolts to withstand the applied loads. The assumed modeling and analysis methodology are seen to be acceptable procedures for seismic qualification of important components of the cooling tower. (authors)

  18. An experimental study on natural draft-dry cooling tower as part of the passive system for the residual decay heat removal

    International Nuclear Information System (INIS)

    An experimental apparatus has been built in order to perform sensitivity analysis on the performance of a natural draft-dry cooling tower. This component plays an important role in the passive system for the residual heat decay removal foreseen in the MARS reactor and in the GCFR of the Generation IV reactors. The sensitivity analysis has investigated: 1) the heat exchanger arrangement; two different arrangements have been considered: a horizontal arrangement, in which a system of electrical heaters are placed at the inlet cross section of the tower, and a vertical arrangement, with the heaters distributed vertically around the circumference of the tower. 2) The shape of the cooling tower; by varying the angle of the shell inclination it is possible to obtain a different shape for the tower itself. An upper and a lower angle inclination were modified and by a calculation procedure eleven different configuration were selected. 3) The effect of cross wind on the tower performance. An equation-based procedure to design the dry-cooling tower is presented. In order to evaluate the influence of the shape and the heat exchanger arrangement on the performance of the cooling tower, a geometrical factor (FG) and a thermal factor (FT) are introduced. By analyzing the experimental results, engineering design relations are obtained to model the cooling tower performance. The comparison between the experimental heat transfer coefficient and the heat transfer coefficient obtained by the mathematical procedure shows that there is a good agreement. The obtained results show that it is possible to evaluate the shape and the heat exchanger arrangement to optimize the performance of the cooling tower either in wind-less condition either in presence of cross wind. (authors)

  19. A multi-layered model for collapse analysis of large reinforced concrete natural-draft cooling towers

    International Nuclear Information System (INIS)

    The modelling of the material behavior of the reinforced concrete is managed by utilizing Bazant's plastic-fracturing theory for the concrete and an elasto-plastic material law, including the Bauschinger effect, for the rebar. The theoretical basis of the model is the shear deformation theory as well as the Kirchhoff-Love theory in the sense of Donnell-Marguerre's approach. To consider the discontinuity of strains in the case of the cracked concrete, mixed FE-models that are based on Hellinger-Reissner's variational principle and its modified version are developed. At last, the damage evolution of a large natural draught cooling tower until collapse is traced numerically. The collapse analysis was performed under dead load and quasi-static wind action. The collapse simulation demonstrates the weakening of the cooling tower under the load combinations according to Euro-code and BTR taking the variability of the material properties into account. (orig./HP)

  20. Temperature effects on the design of cooling tower shells; Zum Einfluss der Temperatur auf die Bemessung von Kuehlturmschalen aus Stahlbeton

    Energy Technology Data Exchange (ETDEWEB)

    Bender, M.; Bockhold, J.; Mark, P. [Bochum Univ. (Germany). Lehrstuhl fuer Stahlbeton- und Spannbetonbau; Meyer, J. [Zerna, Koepper und Partner, Ingenieurgesellschaft fuer Bautechnik, Bochum (Germany)

    2005-11-01

    Bending moments caused by temperature constraints substantially influence required reinforcement quantities in cooling tower shells. Important parameters in linear structural analyses are the extents of characteristic thermal actions and their combinations as well as global reduction factors that account for the loss of stiffness by cracking. The sensitivity to variations in temperature scenarios is presented using numerical simulations of a representative cooling tower shell and the design specifications of BTR-Kuehltuerme (2005). The characteristic design-scenarios are simulated in geometrically and materially nonlinear computations to realistically estimate the loss of stiffness by cracking, the influence of temperature effects on the ultimate load bearing capacity as well as actual extents of steel and concrete stresses. (orig.)

  1. European supercritical water cooled reactor

    International Nuclear Information System (INIS)

    Highlights: ? The HPLWR reactor design is an example of a supercritical water cooled reactor. ? Cladding material tests have started but materials are not yet satisfactory. ? Numerical heat transfer predictions are promising but need further validation. ? The research project is most suited for nuclear education and training. - Abstract: The High Performance Light Water Reactor (HPLWR), how the European Supercritical Water Cooled Reactor is called, is a pressure vessel type reactor operated with supercritical water at 25 MPa feedwater pressure and 500 oC average core outlet temperature. It is designed and analyzed by a European consortium of 10 partners and 3 active supporters from 8 Euratom member states in the second phase of the HPLWR project. Most emphasis has been laid on a core with a thermal neutron spectrum, consisting of small fuel assemblies in boxes with 40 fuel pins each and a central water box to improve the neutron moderation despite the low coolant density. Peak cladding temperatures of the fuel rods have been minimized by heating up the coolant in three steps with intermediate coolant mixing. The containment design with its safety and residual heat removal systems is based on the latest boiling water reactor concept, but with different passive high pressure coolant injection systems to cause a forced convection through the core. The design concept of the steam cycle is indicating the envisaged efficiency increase to around 44%. Moreover, it provides the constraints to design the components of the balance of the plant. The project is accompanied by numerical studies of heat transfer of supercritical water in fuel assemblies and by material tests of candidate cladding alloys, performed by the consortium and supported by additional tests of the Joint Research Centre of the European Commission. Besides the scientific and technical progress, the HPLWR project turned out to be most successful in training the young generation of nuclear engineers in the technologies of light water reactors. More than 20 bachelor or master theses and more than 10 doctoral theses on HPLWR technologies have been submitted at partner organizations of this consortium since the start of this project.

  2. Buffeting along-wind loads on ventilation stack of nuclear power stations due to nearby natural draft cooling towers

    International Nuclear Information System (INIS)

    Buffet loads due to high turbulence wakes of natural draft cooling towers (NDCT) on ventilation stacks of nuclear power stations is analysed using existing theories by making certain assumptions about the scale and intensity of turbulence. This issue can be important since these stacks do not carry any heavy linings as on stacks of thermal power stations and hence are prone to higher buffet loads. Results are compared with some wind tunnel model experimental data and found to give reasonable conservative estimates. (author)

  3. Study of modes of operation water system movement with bypass system towers cooling by Ecosimpro; Estudio de modos de operacion del sistema de agua de circulacion con sistema de bypass de las torres de refrigeracion mediante Ecosimpro

    Energy Technology Data Exchange (ETDEWEB)

    Prieto, J.; Molina, M. C.; Gavilan, C.; Molina, J. J.

    2013-07-01

    The present paper is based on the thermodynamic study of the system of water circulation of the Central Nuclear de Cofrentes. The objective of the study is the operation of the system through different modes of operation, with the aim of analyze the impact of these modes over the operation of the same. For a complete analysis, it has created a computer model of the system through the EcosimPro software, which is the simulation of the operation modes system and through the results, is the analysis of their feasibility.

  4. Present knowledge on physical relations in drift ejection from wet cooling towers and hitherto applied measuring methods to determine the droplet size

    International Nuclear Information System (INIS)

    Modern cooling towers are equipped with drift eliminators. Besides the knowledge of the spray loss ejection rate, the drift spectrum of the spray loss is also of interest. Possibilities of improving the degree of separation of the drift eliminators are shown by means of theories. These considerations are confirmed by measurements. Furthermore, measuring methods of the drift ejection rate and the droplet size determination are given. Finally, drift spectra of various drift eliminator and cooling tower constructions are given. (orig.)

  5. Johnson screen for cooling water intakes

    International Nuclear Information System (INIS)

    Johnson surface-water screens provide an alternative to vertical traveling screens for power plant cooling water intakes. In this paper, flow field modeling is discussed, and a series of case studies is presented. The hydraulic information obtained is discussed as it applies to the exclusion of biota and debris from cooling water intake systems

  6. Efficient Water Management in Water Cooled Reactors

    International Nuclear Information System (INIS)

    One of the IAEA's statutory objectives is to 'seek to accelerate and enlarge the contribution of atomic energy to peace, health and prosperity throughout the world'. One way this objective is achieved is through the publication of a range of technical series. Two of these are the IAEA Nuclear Energy Series and the IAEA Safety Standards Series. According to Article III.A.6 of the IAEA Statute, the safety standards establish 'standards of safety for protection of health and minimization of danger to life and property.' The safety standards include the Safety Fundamentals, Safety Requirements and Safety Guides. These standards are written primarily in a regulatory style, and are binding on the IAEA for its own programmes. The principal users are the regulatory bodies in Member States and other national authorities. The IAEA Nuclear Energy Series comprises reports designed to encourage and assist R and D on, and application of, nuclear energy for peaceful uses. This includes practical examples to be used by owners and operators of utilities in Member States, implementing organizations, academia, and government officials, among others. This information is presented in guides, reports on technology status and advances, and best practices for peaceful uses of nuclear energy based on inputs from international experts. The IAEA Nuclear Energy Series complements the IAEA Safety Standards Series. Water scarcity is becoming one of the most pressing crises affecting the planet. A reliable supply of water and energy is an important prerequisite for sustainable development. A large number of nuclear power reactors are being planned in many developing countries to address these countries' increasing energy demands and their limited fossil resources. New construction is expected in the USA, Europe and Asia, as well. Reducing water use and consumption by nuclear power plants is likely to help developing countries in introducing nuclear power into their energy supply mix. A large number of the countries that have recently begun to consider the introduction of nuclear power are in water scarce regions, which would certainly limit the possibility for deployment of nuclear power plants, in turn hindering these countries' development and energy security. Thus, there is a large incentive to enhance efforts to introduce innovative water use, water management practices and related technologies. Water management for nuclear power plants is gaining interest in IAEA Member States as an issue of vital importance for the deployment of nuclear power. Recent experience has shown that some nuclear power plants are susceptible to prolonged drought conditions, forcing reactors to be shut down or power to be reduced to a minimal level. In some cases, environmental issues have resulted in regulations that limit the possibility for water withdrawal as well as water discharge. Regarding the most common design for cooling nuclear power plants, this has led to a complicated siting procedure for new plants and expensive retrofits for existing ones. The IAEA has already provided its Member States with reports and documents that address the issue. At the height of nuclear power expansion in the 1970s, the need for guidance in the area resulted in publications such as Thermal Discharges at Nuclear Power Stations - Their Management and Environmental Impact (Technical Reports Series No. 155) and Environmental Effects of Cooling Systems (Technical Reports Series No. 202). Today, amid the so-called nuclear renaissance, it is of vital importance to offer guidance to the Member States on the issues and possibilities that nuclear power water management brings. Management of water at nuclear power plants is an important subject during all phases of the construction, operation and maintenance of any nuclear power plant. Water management addresses the issue of securing water for condenser cooling during operation, for construction (during the flushing phase), and for inventory control, including make-up to the primary coolant system and discharge from the radioactive liquid w

  7. Determination of both thermohydraulic and mass-sized parameters of a power unit cooling system on the base of dry tower

    International Nuclear Information System (INIS)

    The block diagram of calculate of thermohydraulic and mass-sized parameters of a cooling system of power units on the basis of dry tower is described. Data of optimization calculations on determination of main parameters dry towers and condenser for power unit of WWER-1000 are indicated. On the basis of the analysis mass-sized and cost characteristics, a choice of optimum parameters of dry towers for a cooling system of the power unit is justified. 10 refs., 5 tabs., 2 figs

  8. Explosive Demolition of a Fire-Water Tower At East Tennessee Technology Park, Oak Ridge TN

    International Nuclear Information System (INIS)

    On June 17, 2006, the Department of Energy (DOE) successfully demolished a ?60 year old fire-water tower (K-1206-E), located at the East Tennessee Technology Park (ETTP) in Oak Ridge, TN, using strategically placed explosive charges. The subject demolition project was executed by MCM Management Corporation and Demolition Dynamics under the management of DoE's prime contractor Bechtel Jacobs Company LLC (BJC). The K-1206-E Fire Water Tower (Tower) supported the ETTP fire water protection system from the mid- 1950's until 1991. The 378,500-L (100,000-gallon) Tower, elevated 53-m (175-feet) above grade, was located in a grassy area within 152-m (500-feet) of several other occupied facilities. Electrical, control circuits and supply water servicing the Tower were deactivated in 2003. Free liquids and sludge were removed from the tank prior to demolition. Demolition of a facility employing explosive demolition at a federal site in the 'post-9/11 era' was a substantial challenge. The subject paper discusses: - the planning and coordination steps that were taken to successfully overcome the challenges prior to the demolition of the empty, deactivated Tower; - the method used for the engineered demolition of the Tower; and - the factors responsible for the successful execution of this demolition project. At least two previous attempts were made to demolish the Tower. In the first attempt, the execution of the project was deferred by the re-allocation of funds. In the subsequent attempt in 2004, the execution of this project was postponed due to concerns that an adjacent facility would have to shut down operations during the duration of mobilization and execution of the project and thereby incur potential financial losses. A total of 51 cubic meters (1,800 cubic feet) of demolition debris was generated, which was compliantly disposed of at a local landfill followed by site restoration

  9. Cross-winds effect on the performance of natural draft wet cooling towers

    International Nuclear Information System (INIS)

    Effects of cross-winds on the thermal performance of natural draft wet cooling towers (NDWCTs) have been investigated. A three-dimensional CFD model has been used to determine the effect of cross-winds on NDWCTs performance surrounded by power plant building structures. The three-dimensional CFD model has utilized the standard k-? turbulence model as the turbulence closure. Two cases have been investigated: a stand-alone NDWCT and two NDWCTs within a proposed power plant structures (PPS). It has been found that regardless of the cross-winds direction, an increase of 1.3 k or more could be predicted at cross-winds speeds greater than 4 m/s. Furthermore, the performance of NDWCTs under cross-winds has been found to be dependent on the three major factors: the structure of the approaching cross-winds and whether it is disturbed or undisturbed, the location of the NDWCT in the wake of the other NDWCT, and the location of the NDWCT in front of/in the wake of the PPS. When comparing results from the stand-alone and from the NDWCTs within PPS simulations, differences in ?Two were found to be less than 1 K for the whole span of cross-winds speeds and could be decreased to 0.7 K for speeds less than 8 m/s. Finally, results obtained from the simulation of a stand-alone NDWCT could be used instead of those from NDWCTs within PPS at a certain cross-winds direction for qualitative comparisons. (authors)

  10. Water Cooled FBNR Nuclear Reactor

    International Nuclear Information System (INIS)

    A new era of nuclear energy is emerging through innovative nuclear reactors that are to satisfy the new philosophies and criteria that are developed by the INPRO program of the International Atomic Energy Agency (IAEA). The IAEA is establishing a new paradigm in relation to nuclear energy. The future reactors should meet the new standards in respect to safety, economy, non-proliferation, nuclear waste, and environmental impact. The Fixed Bed Nuclear Reactor (FBNR) is a small (70 MWe) nuclear reactor that meets all the established requirements. It is an inherently safe and passively cooled reactor that is fool proof against nuclear proliferation. It is simple in design and economic. It can serve as a dual purpose plant to produce simultaneously both electricity and desalinated water thus making it especially suitable to the needs of most of developing countries. FBNR is developed with the support of the IAEA under its program of Small Reactors Without On-Site Refuelling (SRWOSR). The FBNR reactor uses the pressurized water reactor (PWR) technology. It fulfills the objectives of design simplicity, inherent and passive safety, economy, standardization, shop fabrication, easy transportability and high availability. The inherent safety characteristic of the reactor dispenses with the need for containment; however, a simple underground containment is envisaged for the reactor in order to reduce any adverse visual impact. (author)

  11. Legionnaires’ disease from a cooling tower in a community outbreak in Lidköping, Sweden- epidemiological, environmental and microbiological investigation supported by meteorological modelling

    Directory of Open Access Journals (Sweden)

    Ulleryd Peter

    2012-11-01

    Full Text Available Abstract Background An outbreak of Legionnaires’ Disease took place in the Swedish town Lidköping on Lake Vänern in August 2004 and the number of pneumonia cases at the local hospital increased markedly. As soon as the first patients were diagnosed, health care providers were informed and an outbreak investigation was launched. Methods Classical epidemiological investigation, diagnostic tests, environmental analyses, epidemiological typing and meteorological methods. Results Thirty-two cases were found. The median age was 62 years (range 36 – 88 and 22 (69% were males. No common indoor exposure was found. Legionella pneumophila serogroup 1 was found at two industries, each with two cooling towers. In one cooling tower exceptionally high concentrations, 1.2 × 109 cfu/L, were found. Smaller amounts were also found in the other tower of the first industry and in one tower of the second plant. Sero- and genotyping of isolated L. pneumophila serogroup 1 from three patients and epidemiologically suspected environmental strains supported the cooling tower with the high concentration as the source. In all, two L. pneumophila strains were isolated from three culture confirmed cases and both these strains were detected in the cooling tower, but one strain in another cooling tower as well. Meteorological modelling demonstrated probable spread from the most suspected cooling tower towards the town centre and the precise location of four cases that were stray visitors to Lidköping. Conclusions Classical epidemiological, environmental and microbiological investigation of an LD outbreak can be supported by meteorological modelling methods. The broad competence and cooperation capabilities in the investigation team from different authorities were of paramount importance in stopping this outbreak.

  12. Steam-Electric Power-Plant-Cooling Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Sonnichsen, J.C.; Carlson, H.A.; Charles, P.D.; Jacobson, L.D.; Tadlock, L.A.

    1982-02-01

    The Steam-Electric Power Plant Cooling Handbook provides summary data on steam-electric power plant capacity, generation and number of plants for each cooling means, by Electric Regions, Water Resource Regions and National Electric Reliability Council Areas. Water consumption by once-through cooling, cooling ponds and wet evaporative towers is discussed and a methodology for computation of water consumption is provided for a typical steam-electric plant which uses a wet evaporative tower or cooling pond for cooling.

  13. Application of an Optimum Design of Cooling Water System by Regeneration Concept and Pinch Technology for Water and Energy Conservation

    Directory of Open Access Journals (Sweden)

    A. Ataei

    2009-01-01

    Full Text Available In this study, using a combination of Pinch Technology and Mathematical Programming, a new technique is presented in order to grass-root design for a cooling water system to achieve minimum total annual cost. The presented technique is further improved by using patterns from the concept of regeneration recycling in water systems; in a sense that cooling water is regenerated locally by an air cooler. Moreover, in the proposed method, optimum design of cooling tower has been achieved through a mathematical model. Related coding in MATLAB version 7.3 was used for the illustrative example to get optimal values in the proposed cooling water design method computations. The result of the recently introduced design methodology was compared with the conventional and Kim and Smith design methods. The outcomes indicate that by using this new design method, more water and energy can be saved and a lower level of total annual cost can be reached.

  14. Performance analysis of an earth-to-air heat exchanger assisted by a wind tower for passive cooling of buildings in arid and hot climate

    International Nuclear Information System (INIS)

    Highlights: • Combination of two techniques of passive cooling: Wind tower and earth-to-air heat exchangers. • A transient model was developed and validated against both theoretical and experimental data of other works. • The performances of the system are almost insensitive to the variation of tower dimensions. • The annual behaviour of the system is also investigated in this paper. • The cooling potential of the system is higher than that of the traditional cooling tower. - Abstract: In this paper, a new design of passive cooling system which consists in an Earth-to-Air Heat Exchanger (EAHE) assisted by a wind tower is presented. This system is intended for the summer cooling in hot and arid regions of Algeria. A transient analytical model was developed in order to investigate the influence of design parameters on the performance of the EAHE. The model of the EAHE is validated against both theoretical and experimental data carried out by other authors. Since it is well-known that the performance of the EAHE systems is more influenced by the air flow velocity, another model was presented to predict the air velocity inside the buried pipe. Moreover, a burying depth of 2 m was adopted and the period under consideration is July where the ambient temperature exceeds 45 °C. This study was also extended to examine the behaviour of system during the whole year. In addition, a sensitivity survey was curried out to investigate the influence of tower and pipe dimensions on the air flow velocity and the performances of the EAHE. Results showed that the wind tower dimensions (height, cross section) have not an important impact compared to the pipe dimensions (length, diameter). It is found that a tower with a total height of 5.1 m and a cross section area of 0.57 m2 can generate an air flow rate of 592.61 m3/h. Furthermore, it has been also observed that the daily cooling potential reached a maximum of 30.7 kW h corresponding to a pipe length of 70 m. The cooling effectiveness of the system is compared to that of traditional passive cooling system consisting in a wind tower with wet surfaces. The results indicated that the ambient air after passing through the wind tower coupled to the EAHE is colder than of that of the leaving the conventional cooling tower

  15. Alternative cooling water systems, Savannah River Plant, Aiken, South Carolina: Final environmental impact statement

    International Nuclear Information System (INIS)

    This Environmental Impact Statement (EIS) provides environmental input into the selection and implementation of cooling water systems for thermal discharges from the K- and C-Reactors and from a coal-fired powerhouse at the Savannah River Plant. This EIS addresses the potential environmental consequences of constructing and operating once-through and recirculating cooling towers for the K- and C-Reactors; increased pumping to a raw water basin and direct discharge to the Savannah River for a coal-fired powerhouse; and no action. The potential environmental consequences assessed include effects on air and water quality, ecological systems, archaeological resources, endangered species, and wetlands. 172 refs., 27 figs., 59 tabs

  16. Experimental investigation on a one-step centripetal blower as a model of a blower to ventilate cooling towers

    International Nuclear Information System (INIS)

    Model tests were performed on a one-step centripetal blower (impeller external diameter of 1 m) whose aim was to clarify whether this kind of blower is suitable to ventilate a cooling tower. Aside from the investigation of the general operational behaviour, it was above all important in the tests to investigate the sensitivity of the centripetal blower to rotating tearing with regular flow as well as with side wind, as the main difficulty was suspected in controlling the blower with side wind. (orig./LN)

  17. Reinforced concrete corrosion: application of Bayesian networks to the risk management of cooling towers in nuclear plants

    International Nuclear Information System (INIS)

    Degradation modeling of concrete structures uses uncertain variables and leads, using reliability assessment, to time dependant evolution of failure probabilities. However, only few data are generally available to feed models leading to two types of uncertainties: an intrinsic one depending on the modeled phenomena and one related to the precision of the measurements. Each new data available is a piece of information which allows updating the initial prediction. In this article, an example of updating process, based on a Bayesian network, is presented and applied on the corrosion risk of a cooling tower in a nuclear plant. (authors)

  18. Corrosion of reinforced concrete in nuclear plants: application of Bayesian networks to the risk management of cooling towers

    International Nuclear Information System (INIS)

    Degradation modelling of concrete structures uses uncertain variables and leads, using reliability assessment, to time dependant evolution of failure probabilities. However, only few data are generally available to feed models leading to two types of uncertainties: an intrinsic one depending on the modelled phenomena and one related to the precision of the measurements. Each new data available is a piece of information which allows updating the initial prediction. In this article, an example of updating process, based on a Bayesian network, is presented and applied on the corrosion risk of a cooling tower in a nuclear plant. (authors)

  19. Variations of parameters on the turbine outlet at nuclear power plant with dissociating coolant and ''dry'' cooling tower

    International Nuclear Information System (INIS)

    The characteristics of the BRGD-1500 and PWR-1300 nuclear power plants with ''dry'' cooling towers under changing meteorological conditions are compared. It is shown that relative variations of specific volume on the turbine outlet for the BRGD-1500 nuclear power plant are appreciably smaller than that for a conventional nuclear power plant steam turbine. As a result, the turbine of a nuclear power plant with dissociating coolant can operate under the wider outside air temperature range without the risk of blade damaging during the turbine exhaust as compared with the nuclear power plant steam turbines

  20. A cooling water system as a biofilm reactor for the treatment of municipal water

    OpenAIRE

    Cloete, T. E.; Smith, Z.; G. Saayman

    1999-01-01

    In this study, a water cooling tower was used as a low-rate biofilm reactor for treating municipal wastewater. The performance of the system was evaluated at three different flow rates. The biofilm reactor gave the best results at a flow rate of 1.6l/s, namely 43.3% nitrogen removal, 42.3% chemical oxygen demand (COD) removal, 1.7% phosphorus removal and 39.8% suspended solids (SS) removal. These results were achieved with a once-through flow and low organic and hydraulic loads. This type of ...

  1. Thermal calculations for water cooled research reactors

    International Nuclear Information System (INIS)

    The formulae and the more important numerical data necessary for thermic calculations on the core of a research reactor, cooled with low pressure water, are presented. Most of the problems met by the designer and the operator are dealt with (calculations margins, cooling after shut-down). Particular cases are considered (gas release, rough walls, asymmetric cooling slabs etc.), which are not generally envisaged in works on general thermics

  2. Water injection device of cooling water and nuclear reactor

    International Nuclear Information System (INIS)

    A jet pump is disposed to a water injection flow channel below a pressure accumulation vessel incorporating cooling water and pressurized gases. A driving water nozzle in the jet pump is connected to a driving water flow channel having an opening below the liquid surface of cooling water in the pressure accumulation vessel. A sucking channel in communication with the diffuser guide portion of the jet pump is disposed to the bottom of the pressure accumulation vessel. Upon reactor accident, cooling water in the driving water channel is jetted from the driving water nozzle to a throat of the diffuser of the jet pump. With such a procedure, cooling water in the sucking flow channel is sucked into the throat of the diffuser and mixed with the cooling water from the driving water nozzle. As a result, a great amount of cooling water flows to the water injection channel and is injected into a reactor pressure vessel. If the water level in the pressure accumulation vessel is reduced lower than the opening of the driving water flow channel, the operation of the jet pump is stopped. The flow rate of the water injection is changed to small amount only from the sucking flow channel by the stoppage of the jet pump. (I.N.)

  3. Design and application-specific design features of wet cooling towers and their impact on economic efficiency of the cooling system; Einfluss der Auslegung und Auswahl eines Nasskuehlturms auf die Wirtschaftlichkeit der Wasserrueckkuehlanlage

    Energy Technology Data Exchange (ETDEWEB)

    Knopf, M. [GEA Management Gesellschaft fuer Waerme- und Energietechnik mbH, Nonnenhorn (Germany)

    1998-09-01

    Cooling towers and their required and appropriate design features continue to be an issue of debate among owners/operators, planning engineers and manufacturers. Often, the requirements and interests of the parties involved cannot be reconciled. Such incompatible requirements for instance are all as-low-as-possible requirements, relating to cold water temperatures - investment cost - performance requirements - noise emissions. Any requirement on its own can be met without problems, but their combination is the crucial aspect, and of course the compromise to be found has to be as near to an optimal solution as possible. Meeting the requirement of low cold water temperature for instance, with a close approach (a), implies that the cooling tower must be a large structure, needing high investment, which in turn can be justified if the design ensures a higher performance efficiency of the system or equipment to be cooled while reducing operating costs. (orig./CB) [Deutsch] Kuehltuerme und ihre Auslegung geben immer wieder Anlass zu Diskussionen zwischen Betreibern, Planern und Herstellern. Oft stehen sich Forderungen gegenueber, die miteinander nicht in Einklang zu bringen sind, wie z.B. - Kaltwassertemperatur so tief wie moeglich - Investitionskosten so niedrig wie moeglich - Leistungsbedarf so gering wie moeglich - Schallemission so wenig wie moeglich. Jede Forderung fuer sich betrachtet, kann erfuellt werden. Gefragt ist jedoch ein Kompromiss, der - bezogen auf die Gesamtanlage - ein Optimum darstellt. So bedeutet beispielsweise eine geringe Kaltwassertemperatur mit einem kleinen Kuehlgrenzabstand (a) die Wahl eines grossen Kuehlturms mit einer hohen Investitionssumme. Diese ist gerechtfertigt, wenn dadurch der Wirkungsgrad der zu kuehlenden Anlage oder Maschine vergroessert und die Betriebskosten damit verringert werden. (orig.)

  4. Can payments for ecosystem services secure the water tower of Tibet?

    OpenAIRE

    Immerzeel, W.; Stoorvogel, J.J.; Antle, J.

    2008-01-01

    Tibet can be considered as the water tower of Asia and the protection of its water resources crucial. We show that a minimum data approach to model the supply of ecosystem services can potentially be applied to water conservation in Tibet. The approach integrates the spatial heterogeneity of the biophysical environment and the economic behaviour of farmers. A spatially distributed hydrological model is used to simulate the effect of irrigation on evapotranspiration reduction and stream flow e...

  5. The experimental study on the wind turbine’s guide-vanes and diffuser of an exhaust air energy recovery system integrated with the cooling tower

    International Nuclear Information System (INIS)

    Highlights: • On-site exhaust air energy recovery turbine generator mounted above cooling tower. • Energy from wasted wind resources is re-used for electricity generation. • Optimum angle arrangement of guide-vanes and diffusers help to improve wind-flow. • Enclosure solves conventional wind turbine problems. • 13.3% reduction in CO2 emission is expected to be achieved from this system. - Abstract: An assembly of two vertical axis wind turbines (VAWTs) and an enclosure is installed above a cooling tower to harness the discharged wind for electricity generation. The enclosure consists of guide-vanes and diffuser-plates, is used to enhance the rotational speed of the turbines for power augmentation. The angle of the guide-vanes is optimized to ensure the oncoming wind stream impinges the rotor blades of the turbine at an optimum angle. The diffuser-plates are tilted at an optimum angle to increase the discharged airflow rate. The performance of the system is tested in the laboratory followed by a field test on an actual size cooling tower. The VAWT performance is increased in the range of 7–8% with the integration of enclosure. There is no significant difference in the current consumption of the fan motor between the bare cooling tower and the one with installed VAWTs. With the presence of this system, approximately 17.5 GW h/year is expected to be recovered from 3000 units of cooling towers at commercial areas, assuming the cooling tower is driven by a 7.5 kW fan motor and operates 16 h/day. This amount of recovered energy can also be translated into 13% reduction in CO2 emission

  6. Development of a new method of measurement of the polarization resistance to estimate the level of corrosion of the reinforced concrete of cooling towers

    International Nuclear Information System (INIS)

    This paper summarises the results obtained from the numerical simulations of an operative measurement mode of polarization resistance adapted for evaluating the corrosion of reinforced concrete on cooling towers. A simple operative measurement mode of Rp is proposed, adapted for cooling towers submitted to corrosion due to carbonation. By means of numerical experimentations, abacuses and correction laws are built involving the different influencing parameters: steel reinforcement's concrete cover, concrete resistivity and current intensity injected from the counter electrode. Finally, a first application of the proposed procedure for calculating the real value of Rp in laboratory conditions is presented. (authors)

  7. The influence of the static wind load concept on the material requirements for reinforced-concrete natural-draught cooling towers

    International Nuclear Information System (INIS)

    The natural wind is the decisive risk factor in natural-draught cooling towers; therefore, the establishment of an assumed velocity is indispensable for the safety and reliability of the construction. In the framework of a statistical wind concept, static substitution loads for the assumed dynamic wind pressure have been determined, also including dynamic wind effects and the resonance response of the structure. On this basis, it has been studied how wind loads with different periodicity affect the material requirements of reinforced-concrete natural-draught cooling towers. It is found that the additional steel requirements, related to the total building cost, remain within acceptable limits even for extreme wind loads. (orig.)

  8. Air and water cooled modulator

    Science.gov (United States)

    Birx, Daniel L. (Oakley, CA); Arnold, Phillip A. (Livermore, CA); Ball, Don G. (Livermore, CA); Cook, Edward G. (Livermore, CA)

    1995-01-01

    A compact high power magnetic compression apparatus and method for delivering high voltage pulses of short duration at a high repetition rate and high peak power output which does not require the use of environmentally unacceptable fluids such as chlorofluorocarbons either as a dielectric or as a coolant, and which discharges very little waste heat into the surrounding air. A first magnetic switch has cooling channels formed therethrough to facilitate the removal of excess heat. The first magnetic switch is mounted on a printed circuit board. A pulse transformer comprised of a plurality of discrete electrically insulated and magnetically coupled units is also mounted on said printed board and is electrically coupled to the first magnetic switch. The pulse transformer also has cooling means attached thereto for removing heat from the pulse transformer. A second magnetic switch also having cooling means for removing excess heat is electrically coupled to the pulse transformer. Thus, the present invention is able to provide high voltage pulses of short duration at a high repetition rate and high peak power output without the use of environmentally unacceptable fluids and without discharging significant waste heat into the surrounding air.

  9. Operations improvement of the recycling water-cooling systems of sugar mills

    Directory of Open Access Journals (Sweden)

    Shcherbakov Vladimir Ivanovich

    Full Text Available Water management in sugar factories doesn’t have analogues in its complexity among food industry enterprises. Water intensity of sugar production is very high. Circulation water, condensed water, pulp press water and others are used in technological processes. Water plays the main role in physical, chemical, thermotechnical processes of beet processing and sugar production. As a consequence of accession of Russia to the WTO the technical requirements for production processes are changing. The enforcements of ecological services to balance scheme of water consumption and water disposal increased. The reduction of fresh water expenditure is one of the main tasks in economy of sugar industry. The substantial role in fresh water expenditure is played by efficiency of cooling and aeration processes of conditionally clean waters of the 1st category. The article contains an observation of the technologies of the available solutions and recommendations for improving and upgrading the existing recycling water-cooling systems of sugar mills. The authors present the block diagram of the water sector of a sugar mill and a method of calculating the optimal constructive and technological parameters of cooling devices. Water cooling towers enhanced design and upgrades are offered.

  10. Fish-eye view from the water tower towards Jura

    CERN Multimedia

    1977-01-01

    In the very front, the cooling plant for the ISR magnets followed by Storage (housing ISR electric generators)and CAO (Control Accelerator Operation) Buildings (Bld 378-377), and the main Building of the ISR Division (Bld 30). Behind stands the West Hall, followed along the neutrino beam line, by the BEBC building, the building housing the neutrino experiments WA1 and WA18, and the Gargamelle Building.

  11. Wind towers architecture, climate and sustainability

    CERN Document Server

    Bahadori, Mehdi N; Sayigh, Ali

    2014-01-01

    This unique volume provides the only holistic treatment of wind towers, a core aspect of sustainable architecture in hot, arid climates. The authors explain how traditional incarnations of these structures provide significant decreases in energy consumption through their use of renewable wind resources to cool buildings and water storage facilities. Beginning with the underlying scientific principles, the design and operation of wind towers is explained in depth and suggestions for optimization are provided, supported by the authors' findings from recent analytical studies.

  12. COOLING WATER ISSUES AND OPPORTUNITIES AT U.S. NUCLEAR POWER PLANTS

    International Nuclear Information System (INIS)

    This report has been prepared for the Department of Energy, Office of Nuclear Energy (DOE-NE), for the purpose of providing a status report on the challenges and opportunities facing the U.S. commercial nuclear energy industry in the area of plant cooling water supply. The report was prompted in part by recent Second Circuit and Supreme Court decisions regarding cooling water system designs at existing thermo-electric power generating facilities in the U.S. (primarily fossil and nuclear plants). At issue in the courts have been Environmental Protection Agency regulations that define what constitutes 'Best Technology Available' for intake structures that withdraw cooling water that is used to transfer and reject heat from the plant's steam turbine via cooling water systems, while minimizing environmental impacts on aquatic life in nearby water bodies used to supply that cooling water. The report was also prompted by a growing recognition that cooling water availability and societal use conflicts are emerging as strategic energy and environmental issues, and that research and development (R and D) solutions to emerging water shortage issues are needed. In particular, cooling water availability is an important consideration in siting decisions for new nuclear power plants, and is an under-acknowledged issue in evaluating the pros and cons of retrofitting cooling towers at existing nuclear plants. Because of the significant ongoing research on water issues already being performed by industry, the national laboratories and other entities, this report relies heavily on ongoing work. In particular, this report has relied on collaboration with the Electric Power Research Institute (EPRI), including its recent work in the area of EPA regulations governing intake structures in thermoelectric cooling water systems.

  13. COOLING WATER ISSUES AND OPPORTUNITIES AT U.S. NUCLEAR POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    Gary Vine

    2010-12-01

    This report has been prepared for the Department of Energy, Office of Nuclear Energy (DOE-NE), for the purpose of providing a status report on the challenges and opportunities facing the U.S. commercial nuclear energy industry in the area of plant cooling water supply. The report was prompted in part by recent Second Circuit and Supreme Court decisions regarding cooling water system designs at existing thermo-electric power generating facilities in the U.S. (primarily fossil and nuclear plants). At issue in the courts have been Environmental Protection Agency regulations that define what constitutes “Best Technology Available” for intake structures that withdraw cooling water that is used to transfer and reject heat from the plant’s steam turbine via cooling water systems, while minimizing environmental impacts on aquatic life in nearby water bodies used to supply that cooling water. The report was also prompted by a growing recognition that cooling water availability and societal use conflicts are emerging as strategic energy and environmental issues, and that research and development (R&D) solutions to emerging water shortage issues are needed. In particular, cooling water availability is an important consideration in siting decisions for new nuclear power plants, and is an under-acknowledged issue in evaluating the pros and cons of retrofitting cooling towers at existing nuclear plants. Because of the significant ongoing research on water issues already being performed by industry, the national laboratories and other entities, this report relies heavily on ongoing work. In particular, this report has relied on collaboration with the Electric Power Research Institute (EPRI), including its recent work in the area of EPA regulations governing intake structures in thermoelectric cooling water systems.

  14. Materials for advanced water cooled reactors

    International Nuclear Information System (INIS)

    The current IAEA programme in advanced nuclear power technology promotes technical information exchange between Member States with major development programmes. The International Working Group on Advanced Technologies for Water Cooled Reactors recommended to organize a Technical Committee Meeting for the purpose of providing an international forum for technical specialists to review and discuss aspects regarding development trends in material application for advanced water cooled reactors. The experience gained from the operation of current water cooled reactors, and results from related research and development programmes, should be the basis for future improvements of material properties and applications. This meeting enabled specialists to exchange knowledge about structural materials application in the nuclear island for the next generation of nuclear power plants. Refs, figs, tabs

  15. Combined thermal storage pond and dry cooling tower waste heat rejection system for solar-thermal steam-electric power plants. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Guyer, E.C.; Bourne, J.G.; Brownell, D.L.; Rose, R.M.

    1979-02-28

    The thermal performance and economics of the combined thermal storage pond and dry cooling tower waste heat rejection system concept for solar-thermal steam-electric plants have been evaluated. Based on the computer simulation of the operation of southwest-sited solar-thermal plants, it has been determined that the combined pond-tower concept has significant cost and performance advantages over conventional dry cooling systems. Use of a thermal storage pond as a component of the dry cooling system allows a significant reduction in the required dry cooling heat exchange capacity and the associated parasitic power consumption. Importantly, it has been concluded that the combined pond-tower dry cooling system concept can be employed to economically maintain steam condensing temperatures at levels normally achieved with conventional evaporative cooling systems. An evaluation of alternative thermal storage pond design concepts has revealed that a stratified vertical-flow cut-and-fill reservoir with conventional membrane lining and covering would yield the best overall system performance at the least cost.

  16. The atmospheric cooling of nuclear power stations

    International Nuclear Information System (INIS)

    Four different types of nuclear reactor are considered: light water reactors, high temperature reactors with steam circulation and with direct gas turbine circulation, and fast breeder reactors. Wet and dry cooling towers are described and experimental studies carried out using cooling tower models are presented. (G.T.H.)

  17. A study on the formation of fouling in a heat exchanging system for Han-river water as cooling water

    International Nuclear Information System (INIS)

    Scale is formed when hard water is heated or cooled in heat transfer equipments such as heat exchangers, condensers, evaporators, cooling towers, boilers, and pipe walls. When scale deposits in a heat exchanger surface, it is traditionally called fouling. The objective of the present study is to investigate the formation of fouling in a heat exchanging system. A lab-scale heat exchanging system is built-up to observe and measure the formation of fouling experimentally. Water analyses are conducted to obtain the properties of Han river water. In the present study a microscopic observation is conducted to visualize the process of scale formation. Hardness of Han-river water is higher than that of tap water in Seoul

  18. Thermohydraulic relationships for advanced water cooled reactors

    International Nuclear Information System (INIS)

    This report was prepared in the context of the IAEA's Co-ordinated Research Project (CRP) on Thermohydraulic Relationships for Advanced Water Cooled Reactors, which was started in 1995 with the overall goal of promoting information exchange and co-operation in establishing a consistent set of thermohydraulic relationships which are appropriate for use in analyzing the performance and safety of advanced water cooled reactors. For advanced water cooled reactors, some key thermohydraulic phenomena are critical heat flux (CHF) and post CHF heat transfer, pressure drop under low flow and low pressure conditions, flow and heat transport by natural circulation, condensation of steam in the presence of non-condensables, thermal stratification and mixing in large pools, gravity driven reflooding, and potential flow instabilities. The objectives of the CRP are (1) to systematically list the requirements for thermohydraulic relationships in support of advanced water cooled reactors during normal and accident conditions, and provide details of their database where possible and (2) to recommend and document a consistent set of thermohydraulic relationships for selected thermohydraulic phenomena such as CHF and post-CHF heat transfer, pressure drop, and passive cooling for advanced water cooled reactors. Chapter 1 provides a brief discussion of the background for this CRP, the CRP objectives and lists the participating institutes. Chapter 2 provides a summary of important and relevant thermohydraulic phenomena for advanced water cooled reactors on the basis of previous work by the international community. Chapter 3 provides details of the database for critical heat flux, and recommends a prediction method which has been established through international co-operation and assessed within this CRP. Chapter 4 provides details of the database for film boiling heat transfer, and presents three methods for predicting film boiling heat transfer coefficients developed by institutes participating in this CRP. Chapter 5 compiles a range of pressure drop correlations, and reviews assessments of these relations and the resulting recommendations. Chapter 6 provides general remarks and conclusions, and comments on future research needs in thermohydraulics of advanced water cooled reactors

  19. Organohalogen products from chlorination of cooling water at nuclear power stations

    International Nuclear Information System (INIS)

    Eight nuclear power units at seven locations in the US were studied to determine the effects of chlorine, added as a biocide, on the composition of cooling water discharge. Water, sediment and biota samples from the sites were analyzed for total organic halogen and for a variety of organohalogen compounds. Haloforms were discharged from all plants studied, at concentrations of a few ?g/L (parts-per-billion). Evidence was obtained that power plants with cooling towers discharge a significant portion of the haloforms formed during chlorination to the atmosphere. A complex mixture of halogenated phenols was found in the cooling water discharges of the power units. Cooling towers can act to concentrate halogenated phenols to levels approaching those of the haloforms. Examination of samples by capillary gas chromatography/mass spectrometry did not result in identification of any significant concentrations of lipophilic base-neutral compounds that could be shown to be formed by the chlorination process. Total concentrations of lipophilic (Bioabsorbable) and volatile organohalogen material discharged ranged from about 2 to 4 ?g/L. Analysis of sediment samples for organohalogen material suggests that certain chlorination products may accumulate in sediments, although no tissue bioaccumulation could be demonstrated from analysis of a limited number of samples. 58 references, 25 figures, 31 tables

  20. Investigations of effects of thermal discharges in Rhine river waters. Part of a coordinated programme on the physical and biological effects of cooling systems and thermal discharges at nuclear power plants

    International Nuclear Information System (INIS)

    The report envisages two aspects of cooling systems: heat exchange between water and atmosphere; cooling tower plume modelling. The author gives the estimated ''cooling capacity'' of German rivers and estuaries and describes a station at Rheinhausen, measuring directly the heat exchange between the river Rhine and the atmosphere. The influence of meteorological and topographical parameters is discussed and the total incertainty in extrapolating formular is assessed. A number of field studies have been carried out to measure plume behaviour of cooling towers and to provide the data basis for comparison of existing models. The average plume rise is well predicted. The experimental programme carried out in Germany since 1973 is described. The one dimensional models TOWER and SAUNA.S are in agreement with experimental results except for short plumes. The last plume model WALKURE shows considerable improvement. It is specially suited for the calculations of the cooling tower plume behaviour under influence of temperature and humidity stratifications in the ambient atmosphere

  1. Climate Change Will Affect the Asian Water Towers

    Science.gov (United States)

    Immerzeel, Walter W.; van Beek, Ludovicus P. H.; Bierkens, Marc F. P.

    2010-06-01

    More than 1.4 billion people depend on water from the Indus, Ganges, Brahmaputra, Yangtze, and Yellow rivers. Upstream snow and ice reserves of these basins, important in sustaining seasonal water availability, are likely to be affected substantially by climate change, but to what extent is yet unclear. Here, we show that meltwater is extremely important in the Indus basin and important for the Brahmaputra basin, but plays only a modest role for the Ganges, Yangtze, and Yellow rivers. A huge difference also exists between basins in the extent to which climate change is predicted to affect water availability and food security. The Brahmaputra and Indus basins are most susceptible to reductions of flow, threatening the food security of an estimated 60 million people.

  2. Coolant technology of water cooled reactors. V. 1: Chemistry of primary coolant in water cooled reactors

    International Nuclear Information System (INIS)

    This report is a summary of the work performed within the framework of the Coordinated Research Programme on Investigations on Water Chemistry Control and Coolant Interaction with Fuel and Primary Circuit Materials in Water Cooled Power Reactors organized by the IAEA and carried out from 1987 to 1991. It is the continuation of a programme entitled Reactor Water Chemistry Relevant to Coolant-Cladding Interaction (IAEA-TECDOC-429), which ran from 1981 to 1986. Subsequent meetings resulted in the title of the programme being changed to Coolant Technology of Water Cooled Reactors. The results of this Coordinated Research Programme are published in four volumes with an overview in the Technical Reports Series. The titles of the volumes are: Volume 1: Chemistry of Primary Coolant in Water Cooled Reactors; Volume 2: Corrosion in the Primary Coolant Systems of Water Cooled Reactors; Volume 3: Activity Transport Mechanisms in Water Cooled Reactors; Volume 4: Decontamination of Water Cooled Reactors. These publications should be of interest to experts in water chemistry at nuclear power plants, experts in engineering, fuel designers, research and development institutes active in the field and to consultants to these organizations. Refs, figs and tabs

  3. Method to remove the waste heat from the cooling circuit of industrial plants

    Energy Technology Data Exchange (ETDEWEB)

    Wieser, R.

    1977-05-18

    Improving present cooling methods in order to lower the temperature in the cooling circuit of an industrial plant and thus to increase the efficiency of the plant are described. This is achieved by removing part of the heat with the aid of fresh water led through a heat exchanger on the secondary side which is connected in series with the dry cooling tower in the cooling circuit. The fresh water is cooled in a wet cooling tower.

  4. Supercritical-pressure light water cooled reactors

    CERN Document Server

    Oka, Yoshiaki

    2014-01-01

    This book focuses on the latest reactor concepts, single pass core and experimental findings in thermal hydraulics, materials, corrosion, and water chemistry. It highlights research on supercritical-pressure light water cooled reactors (SCWRs), one of the Generation IV reactors that are studied around the world. This book includes cladding material development and experimental findings on heat transfer, corrosion and water chemistry. The work presented here will help readers to understand the fundamental elements of reactor design and analysis methods, thermal hydraulics, materials and water

  5. The DA?NE water cooling system

    International Nuclear Information System (INIS)

    a water cooling system for the DA?NE complex has been constructed and operated successfully. Special care has been taken to improve system reliability and temperature accuracy during the design, the realization and the commissioning; specific solutions have been adopted to meet accelerator requirements. Here the design, specifications and results of performance tests are revised

  6. Anomalous Effects in Air While Cooling Water

    OpenAIRE

    Sardo, Rachel; Brownridge, James D.

    2008-01-01

    Water is a unique compound with many anomalies and properties not fully understood. Designing an experiment in the laboratory to study such anomalies, we set up a series of experiments where a tube was placed inside a sealed container with thermocouples attached to the outer surface of the tube and in the air adjacent to the tube. Alternately, deionized water and other compounds were added to the tube and cooled to freezing. Several of the thermocouples suspended in the air ...

  7. Seismic analysis of two 1050 mm diameter heavy water upgrading towers for 235 MWe Kakrapar Atomic Power Plant Site

    International Nuclear Information System (INIS)

    This report deals with the analysis carried out for the evaluation of earthquake induced stresses and deflections in two 1050 mm diameter heavy water upgrading towers for Kakrapar Atomic Power Plant Site. The analysis of upgrading tower has been carried out for two mutually perpendicular horizontal excitations and the vertical excitation. The upgrading towers have been analysed using beam model taking into account soil-structure interaction. response spectrum analysis has been carried out using site spectra for 235 MWe KAPP site. The seismic analysis has been carried out for both the towers with supporting structure along with concrete pedestals and raft foundation. The towers have been checked for their stability due to compressive stresses to avoid buckling so that the nearby safety related structures are not damaged in the event of SSE loading. (author). 13 refs., 11 figs., 14 tabs

  8. Seismic analysis of two 1050 mm diameter heavy water upgrading towers for 235 MWe Kaiga Atomic Power Plant Site

    International Nuclear Information System (INIS)

    This report deals with the analysis carried out for the evaluation of earthquake induced stresses and deflections in two 1050 mm diameter heavy water upgrading towers for Kaiga Atomic Power Plant Site. The analysis of upgrading tower has been carried out for two mutually perpendicular horizontal excitations and one vertical excitation applied simultaneously. The upgrading towers have been analysed using beam model taking into account soil-structure interaction. Response spectrum analysis has been carried out using site spectra for 235 MWe Kaiga reactor site. The seismic analysis has been performed for both the towers with supporting structure along with concrete pedestals and raft foundation. The towers have been checked for its stability due to compressive stresses to avoid buckling so that the nearby safety related structures are not geopardised in the event of safe shutdown earthquake (SSE) loading. (author). 14 refs., 12 figs., 18 tabs

  9. Seismic analysis of two heavy water upgrading towers for 500 MWe Tarapur Atomic Power Plant-3 and 4

    International Nuclear Information System (INIS)

    The report deals with the analysis carried out for the evaluation of earthquake induced stresses and deflections in two 1500 mm diameter heavy water upgrading towers for Tarapur Atomic Power Plant-3 and -4. The analysis of upgrading towers has been carried out for two mutually perpendicular horizontal excitations and one vertical excitation applied simultaneously. The upgrading towers have been analysed using beam model taking into account soil-structure interaction. Response spectrum analysis has been carried out using envelope spectra for 500 MWe sites. The seismic analysis has been carried out for the towers with supporting structure along with concrete pedestals and raft foundation. The towers have been checked for their stability due to compressive stresses to avoid buckling so that safety of the nearby structures is not damaged even in the event of SSE (Safe Shutdown Earthquake) loading. (author). 16 refs., 11 figs., 18 tabs

  10. MHD/gas turbine systems designed for low cooling water requirements

    Science.gov (United States)

    Annen, K. D.; Eustis, R. H.

    1983-12-01

    The MHD/gas turbine combined-cycle system has been designed specifically for applications where the availability of cooling water is very limited. The base case systems which were studied consist of a coal-fired MHD plant with an air turbine bottoming plant and require no cooling water. In addition to the base case systems, systems were considered which included the addition of a vapor cycle bottoming plant to improve the thermal efficiency. These systems require a small amount of cooling water. The results show that the MHD/gas turbine systems have very good thermal and economic performances. The base case I MHD/gas turbine system (782 MWe) requires no cooling water, has a heat rate which is 13 percent higher, and a cost of electricity which is only 7 percent higher than a comparable MHD/steam system (878 MWe) having a cooling tower heat load of 720 MW. The case I vapor cycle bottomed systems have thermal and economic performances which approach and even exceed those of the MHD/steam system, while having substantially lower cooling water requirements. Performances of a second-generation MHD/gas turbine system and an oxygen-enriched, early commercial system are also evaluated. An analysis of nitric oxide emissions shows compliance with emission standards.

  11. MHD/gas turbine systems designed for low cooling water requirements

    International Nuclear Information System (INIS)

    The MHD/gas turbine combined-cycle system has been designed specifically for applications where the availability of cooling water is very limited. The base case systems which were studied consist of a coal-fired MHD plant with an air turbine bottoming plant and require no cooling water. In addition to the base case systems, systems were considered which included the addition of a vapor cycle bottoming plant to improve the thermal efficiency. These systems require a small amount of cooling water. The results show that the MHD/gas turbine systems have very good thermal and economic performances. The base case I MHD/gas turbine system (782 MW /SUB e/ ) requires no cooling water, has a heat rate which is 13% higher, and a cost of electricity which is only 7% higher than a comparable MHD/steam system (878 MW /SUB e/ ) having a cooling tower heat load of 720 MW. The case I vapor cycle bottomed systems have thermal and economic performances which approach and even exceed those of the MHD/steam system, while having substantially lower cooling water requirements. Performances of a second-generation MHD/gas turbine system and an oxygen-enriched, early commercial system are also evaluated. An analysis of nitric oxide emissions shows compliance with emission standards

  12. Reduction of Langelier index of cooling water by electrolytic treatment with stainless steel electrode

    Scientific Electronic Library Online (English)

    Rapeepat, Rungvavmanee; Chantaraporn, Phalakornkule.

    Full Text Available The efficiency of electrolytic treatment in reducing the Langelier saturation index (LSI) of the cooling water from a cooling tower of a textile industry was investigated. Sacrificial anodes were employed which prevent obnoxious chlorine generation. A series of batch experiments using stainless stee [...] l electrodes were conducted with 4 different current densities (5, 7, 10 and 15 A/m²) and 6 different electrolysis times (20, 30, 40, 50, 60 and 70 min). The use of 7 A/m² for 50 min electrolysis time yielded a satisfactory efficiency in reducing the LSI index from 2.57 to zero, indicating that the treated water was of sufficient quality to be reused in the cooling process.

  13. Implementing the power station cooling water standard AS 5059-2003

    Energy Technology Data Exchange (ETDEWEB)

    Spowart, G. [Loy Yang Power, Traralgon (Australia)

    2004-04-01

    The new Australian standard ''power station cooling tower systems - management of legionnaires' disease health risk'' (AS 5059-2003) was released in September 2003 following several years of work by a large number of chemists in the power industry. The standard uses a risk based methodology to allow power stations to develop plans to minimise legionella levels in cooling water systems. This paper addresses the issues that stations are likely to encounter in meeting the requirements of the standard. The paper discusses the impacts of the: cooling system design, operating and maintenance philosophies, characteristics of the makeup water, biocide treatment program, alternative treatment program, monitoring requirements and reporting requirements. (orig.)

  14. Use of Produced Water in Recirculating Cooling Systems at Power Generating Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Kent Zammit; Michael N. DiFilippo

    2005-07-01

    The purpose of this study is to evaluate produced water as a supplemental source of water for the San Juan Generating Station (SJGS). This study incorporates elements that identify produced water volume and quality, infrastructure to deliver it to SJGS, treatment requirements to use it at the plant, delivery and treatment economics, etc. SJGS, which is operated by Public Service of New Mexico (PNM) is located about 15 miles northwest of Farmington, New Mexico. It has four units with a total generating capacity of about 1,800 MW. The plant uses 22,400 acre-feet of water per year from the San Juan River with most of its demand resulting from cooling tower make-up. The plant is a zero liquid discharge facility and, as such, is well practiced in efficient water use and reuse. For the past few years, New Mexico has been suffering from a severe drought. Climate researchers are predicting the return of very dry weather over the next 30 to 40 years. Concern over the drought has spurred interest in evaluating the use of otherwise unusable saline waters. This deliverable describes possible test configurations for produced water demonstration projects at SJGS. The ability to host demonstration projects would enable the testing and advancement of promising produced water treatment technologies. Testing is described for two scenarios: Scenario 1--PNM builds a produced water treatment system at SJGS and incorporates planned and future demonstration projects into the design of the system. Scenario 2--PNM forestalls or decides not to install a produced water treatment system and would either conduct limited testing at SJGS (produced water would have to be delivered by tanker trucked) or at a salt water disposal facility (SWD). Each scenario would accommodate demonstration projects differently and these differences are discussed in this deliverable. PNM will host a demonstration test of water-conserving cooling technology--Wet Surface Air Cooling (WSAC) using cooling tower blowdown from the existing SJGS Unit 3 tower--during the summer months of 2005. If successful, there may be follow-on testing using produced water. WSAC is discussed in this deliverable. Recall that Deliverable 4, Emerging Technology Testing, describes the pilot testing conducted at a salt water disposal facility (SWD) by the CeraMem Corporation. This filtration technology could be a candidate for future demonstration testing and is also discussed in this deliverable.

  15. Simulación de una Torre de Enfriamiento Mecánica Comparada con Curvas Experimentales Simulation of a Mechanical Cooling Tower Compared with Experimental Curves

    Directory of Open Access Journals (Sweden)

    Jader D Alean

    2009-01-01

    Full Text Available El objetivo del trabajo es modelar y simular una torre de enfriamiento mecánica forzada a escala piloto. Las variables físicas se correlacionaron a partir de la transferencia de calor y materia y los resultados de la simulación son analizados mediante graficas que muestran la variación de la humedad, flujo de agua, calor latente, calor sensible, calor total, temperatura del agua y del aire. El coeficiente de transferencia de materia se obtuvo a partir de los datos experimentales y la solución numérica del modelo se obtuvo con el método Runge-Kutta en Matlab. La verificación de los resultados fue realizada, comparando las curvas simuladas con las curvas experimentales. Se concluye que la cercanía entre las curvas depende del coeficiente de transferencia de materia.The objective of this work was the modeling and simulation of a pilot-scale mechanical enforced cooling tower. The physical variables were correlated from the heat and mass transfer and the simulation results were analyzed using graphs showing the change in humidity, water flow, latent heat, heat sensitive, total heat, water temperature and air. The mass transfer coefficient was obtained from experimental data and the numerical solution of the model was obtained using Runge-Kutta method in Matlab. Comparison between stimulation results and experimental data was done. It is concluded that the shape of the curves and the deviations of the simulated results depend on the mass transfer coefficient.

  16. Simulación de una Torre de Enfriamiento Mecánica Comparada con Curvas Experimentales / Simulation of a Mechanical Cooling Tower Compared with Experimental Curves

    Scientific Electronic Library Online (English)

    Jader D, Alean; Gail A, Gutiérrez; Farid, Chejne; Marlon J, Bastidas.

    Full Text Available El objetivo del trabajo es modelar y simular una torre de enfriamiento mecánica forzada a escala piloto. Las variables físicas se correlacionaron a partir de la transferencia de calor y materia y los resultados de la simulación son analizados mediante graficas que muestran la variación de la humedad [...] , flujo de agua, calor latente, calor sensible, calor total, temperatura del agua y del aire. El coeficiente de transferencia de materia se obtuvo a partir de los datos experimentales y la solución numérica del modelo se obtuvo con el método Runge-Kutta en Matlab. La verificación de los resultados fue realizada, comparando las curvas simuladas con las curvas experimentales. Se concluye que la cercanía entre las curvas depende del coeficiente de transferencia de materia. Abstract in english The objective of this work was the modeling and simulation of a pilot-scale mechanical enforced cooling tower. The physical variables were correlated from the heat and mass transfer and the simulation results were analyzed using graphs showing the change in humidity, water flow, latent heat, heat se [...] nsitive, total heat, water temperature and air. The mass transfer coefficient was obtained from experimental data and the numerical solution of the model was obtained using Runge-Kutta method in Matlab. Comparison between stimulation results and experimental data was done. It is concluded that the shape of the curves and the deviations of the simulated results depend on the mass transfer coefficient.

  17. Cooling tower restoration in the joint nuclear power station Neckar 1

    International Nuclear Information System (INIS)

    Since the starting operation of the Power Station GKN I (Joint Nuclear Power Station Neckar I) in the year 1976, the cell cooler of the plant was, except for those cases in which continuous-flow cooling was possible, continually in operation. Aim of the restoration, after an operational time of 17 years, is a further constructional and thermal service life of about 15 to 20 years. (orig.)

  18. From chip to cooling tower data center modeling: Part II Influence of chip temperature control philosophy

    OpenAIRE

    Walsh, EJ; Breen, TJ; Punch, J.; Shah, AJ; Bash, CE

    2010-01-01

    The chiller cooled data center environment consists of many interlinked elements that are usually treated as individual components. This chain of components and their influences on each other must be considered in determining the benefits of any data center design and operational strategies seeking to improve efficiency, such as temperature control fan algorithms. Using the models developed in part I of this work, this paper extends the analysis to include the electronics within the rack thro...

  19. Effect of cold inflow on chimney height of natural draft cooling towers

    International Nuclear Information System (INIS)

    Highlights: ? Natural convection data were obtained from an air-cooled heat exchanger model. ? The extent of cold inflow was quantified to relate to the decrease in effective chimney height. ? Installation of wire mesh screen on chimney outlet blocked off cold inflow to improve the chimney efficiency. ? Evidence of existence of effective plume-chimney for when cold inflow was blocked off warrants further work. - Abstract: Temperature and pressure drop data obtained from an air-cooled heat exchanger model with cross-sectional flow areas of 0.56 m2, 1.00 m2 and 2.25 m2 operating under natural convection are presented that indicate significant cold inflow, resulting in the reduction of effective chimney height. Cold inflows encountered in actual applications where the Froude number is typically 0.2, may not be as severe as described in this paper, which was of the order of 10?6–10?4. Additional tests on smaller scale models appeared to favor the explanation that the occurrence of cold inflow in the air-cooled heat exchanger model was primarily due to the relative ease in either drawing cold air from inlet or from outlet, and to a lesser extent the Froude number of the chimney or the critical velocity estimated by formula. A CFD study will bring much understanding of the phenomenon for the different situations.

  20. WET/DRY COOLING AND COOLING TOWER BLOWDOWN DISPOSAL IN SYNTHETIC FUEL AND STEAM-ELECTRIC POWER PLANTS

    Science.gov (United States)

    This report extends the results of a previous study dealing with the detailed determination of consumptive water use and wet-solids residuals for coal and oil shale conversion plants and coal-fired steam-electric power generation plants located in the western United States. The p...

  1. Laboratory Experiments with Supersonic Radiatively Cooled Jets: Jet Deflection via Crosswinds and Magnetic Tower Outflows

    International Nuclear Information System (INIS)

    We present results of high energy density laboratory experiments on the production of supersonic radiatively cooled plasma jets with dimensionless parameters (Mach number ?30, cooling parameter ?1 and density contrast ?j/?a ?10) similar to those in YSO jets. The jets are produced using two modifications of wire array Z-pinch driven by 1MA, 250ns current pulse of MAGPIE facility at Imperial College London. In the first set of experiments the produced jets are purely hydrodynamic and are used to study deflection of the jets by the plasma cross-wind, including the structure of internal oblique shocks in the jets. In the second configuration the jets are driven by the pressure of the toroidal magnetic field and this configuration is relevant to the astrophysical models of jet launching mechanisms. Modifications of the experimental configuration allowing addition of the poloidal magnetic field and angular momentum to the jets are also discussed. We also present three-dimensional resistive magneto-hydrodynamic (MHD) simulations of the experiments and discuss the scaling of the experiments to the astrophysical systems

  2. Kinetic model for predicting the concentrations of active halogens species in chlorinated saline cooling waters. Final report

    International Nuclear Information System (INIS)

    A kinetic model has been developed for describing the speciation of chlorine-produced oxidants in seawater as a function of time. The model is applicable under a broad variety of conditions, including all pH range, salinities, temperatures, ammonia concentrations, organic amine concentrations, and chlorine doses likely to be encountered during power plant cooling water chlorination. However, the effects of sunlight are not considered. The model can also be applied to freshwater and recirculating water systems with cooling towers. The results of the model agree with expectation, however, complete verification is not feasible at the present because analytical methods for some of the predicted species are lacking

  3. Kinetic model for predicting the concentrations of active halogens species in chlorinated saline cooling waters. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Haag, W.R.; Lietzke, M.H.

    1981-08-01

    A kinetic model has been developed for describing the speciation of chlorine-produced oxidants in seawater as a function of time. The model is applicable under a broad variety of conditions, including all pH range, salinities, temperatures, ammonia concentrations, organic amine concentrations, and chlorine doses likely to be encountered during power plant cooling water chlorination. However, the effects of sunlight are not considered. The model can also be applied to freshwater and recirculating water systems with cooling towers. The results of the model agree with expectation, however, complete verification is not feasible at the present because analytical methods for some of the predicted species are lacking.

  4. Micro-Organisms of Cooling Tower Problems and How to Manage Them

    OpenAIRE

    Amir-Samimi

    2013-01-01

    Microorganisms are found everywhere in nature. In air, water and soil are scattered and they are crucial role in the health of humans and animals. many microorganisms are beneficial, while others are pathogenic. Life and activity of microbial processes are effective in many industries. For example, Zugloel bacteria in activated sludge and in the refinery are benefit. They make sludge polysaccharides that help other bacteria digest organic material otherwise organic material into the water rec...

  5. Cooling water purification by means of ozone; Koelwater reiniging met ozon

    Energy Technology Data Exchange (ETDEWEB)

    Van den Einden, A.W.J. [DHV AIB, Eindhoven (Netherlands)

    2003-08-01

    The advantages of the use of ozone to clean water from cooling towers are highlighted. [Dutch] Waterbehandeling van het koelwater van koeltorens is noodzakelijk en wordt voomamelijk gedaan door toevoeging van chemicalien. Ozon als vervanger van de gebruikelijke chemicalien lijkt zeer geschikt om koeltorenwater te reinigen. Wordt aan de technische randvoorwaarden voldaan, dan is het een ideaal reinigingsmiddel dat met geringe operationele kosten de waterkwaliteit onderhoudt. Naast de reinigende eigenschappen, is het een groot voordeel dat de chemische belasting op het milieu en de daarbij komende locale lozingskosten sterk afnemen.

  6. Effects of discharging warm cooling water from a nuclear power station into the Upper Elbe

    International Nuclear Information System (INIS)

    The permissible discharge of heat to a watercourse is determined by the limiting values of the temperature and degree of warming of river and cooling water. If these limiting values are exceeded the heat transfer to the watercourse must be restricted. This can be achieved by installing a cooling tower or by reducing the output of the power station. The most economic solution from the point of view of the overall undertaking can be achieved by a combination of both methods. Detailed statistical analyses of outflows and of river water temperatures are essential, in order to determine the most favourable variants. The paper reports on such a statistical evaluation using as an example the Upper Elbe and a nuclear power station. (orig.)

  7. MIC in Circulating Cooling Water System

    OpenAIRE

    Li Zhang; Yajun Zhang; Jin Wang; Ping Xu; Zhaoyi Xu

    2012-01-01

    MIC is one of the main problems of circulating cooling water system. The direct economic loss by MIC is about 300 to 500 billion dollars. It is good to understand MIC in order to control MIC. Source and species of microorganisms was introduced firstly. There are three kinds of microorganisms in the system, including bacteria, fungi and algae. Species of these microorganisms are shown in the paper. Then, mechanisms of MIC are analysed. Although there is no universal mechanism of MIC, MIC is st...

  8. Cooling methods for power plants

    International Nuclear Information System (INIS)

    There are some results of measurements carried out on the wet cooling tower 275 MWe at TE Sostanj and on the experimental cooling tower at Jozef Stefan Institute, as well. They are including: the measurements of the output air conditions, the measurements of the cross current of water film and vapour-air flowing through two plates, and the distribution of velocity in boundary layer measured by anemometer

  9. Feasibility to cool component cooling water with containment spray system in nuclear power plant

    International Nuclear Information System (INIS)

    The feasibility to cool component cooling water with refueling water storage tank through the containment spray test line, spray pump and spray heat exchanger in the event of loss of essential service water in nuclear power plant is analyzed. It is concluded that after a loss of essential service water, the cooling component cooling water system with containment spray system is difficult to succeed in summer, but it is successful in winter if only operator switches off the unnecessary heat loads within 8 min. (authors)

  10. Pollution of public waters by condenser cooling water of power plants

    International Nuclear Information System (INIS)

    Due to the falling oxygen consentration in flowing waters through temperature rises resulting from power plant industry, the construction and operation of ventilation systems will be made a condition in water rights in industries. This kind of cooling water-back-cooling system which saturates the warm condenser cooling water with air and introduces it into the river is described. The cooling-down of the warm cooling water is illustrated in a Mollier diagram. (GL)

  11. Seismic analysis of 1500 mm diameter heavy water upgrading tower for 500 MWe sites and 235 MWe Kaiga site

    International Nuclear Information System (INIS)

    This report deals with the analysis carried out for the evaluation of earthquake induced stresses and deflections in the single 1500 mm diameter heavy water upgrading tower for 500 MWe sites and 235 MWe Kaiga site. The analysis of upgrading tower has been carried out for two mutually perpendicular horizontal excitations and the vertical excitation. The upgrading tower has been analysed using beam model taking into account soil-structure interaction. Response spectrum analysis has been carried out using envelop spectra for 500 MWe site and the site spectra for Kaiga. The seismic analysis has been carried out for two cases viz. for tower alone and for tower with supporting structure along with concrete pedestals and raft foundation. The tower has been checked for its stability due to compressive stresses to avoid buckling so that nearby safety related structures are not damaged in the event of SSE loading. The report addresses in detail about the calculation of critical buckling stresses due to various modes of buckling failure and also makes a comparative study of various available international codes in this respect. (author). 15 refs., 20 figs., 18 tabs

  12. Comparative validation of three water cooling coil models

    OpenAIRE

    Gendebien, Samuel; Bertagnolio, Stéphane; Lemort, Vincent

    2010-01-01

    Water cooling coils are widely used in common HVAC systems. Accurate and robust cooling coil simulation models are required to perform reliable calculations of building cooling needs. Many different cooling coil simulation models were developed during the last decades. The most commonly used cooling coil models are presented and compared in terms of implementation in the first part of the paper. A simplified variable boundary model is presented and comparatively and empirically validated to t...

  13. Repair criteria and methods of repair for concrete structures of nuclear power plants - Particular application on natural draught cooling towers in belgium

    International Nuclear Information System (INIS)

    A previous paper was presented at the OCDE Workshop held 22-23 March 2000 in Brussels explaining different aspects of the techniques used for 'Instrumentation and monitoring of natural draught cooling towers in Belgium'. These monitoring and preventive techniques are now applied in Belgium since already more then 10 years by Tractebel on the towers of the nuclear plants. These huge constructions have to sustain considerable physical, chemical and biological loads. As one can figure out, and as years go by, these inspections showed deterioration of which type, progress, quantity eventually led to the need of repairing these structures. The present paper goes over 4 main different sorts of defects (beam supports breaking, fast carbonation rate, concrete porosity, and a series of local deteriorations like insufficient concrete cover, cracking, gravel pockets, corroded reinforcement) encountered on 3 cooling towers situated in Belgium, and affecting the shell as well as the inner structures. The diagnosis, the choice of the appropriate repair techniques and products which will avoid having to face much higher costs in the future are explained. It also gives an illustration of the works carried on site and points out the uncommon and complex aspects the treatment of such a construction implies (planning, both horizontal and vertical curved shape, works at great height,...). (author)

  14. Electrochemistry of Water-Cooled Nuclear Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Macdonald, Dgiby; Urquidi-Macdonald, Mirna; Pitt, Jonathan

    2006-08-08

    This project developed a comprehensive mathematical and simulation model for calculating thermal hydraulic, electrochemical, and corrosion parameters, viz. temperature, fluid flow velocity, pH, corrosion potential, hydrogen injection, oxygen contamination, stress corrosion cracking, crack growth rate, and other important quantities in the coolant circuits of water-cooled nuclear power plants, including both Boiling Water Reactors (BWRs) and Pressurized Water Reactors (PWRs). The model is being used to assess the three major operational problems in Pressurized Water Reactors (PWR), which include mass transport, activity transport, and the axial offset anomaly, and provide a powerful tool for predicting the accumulation of SCC damage in BWR primary coolant circuits as a function of operating history. Another achievement of the project is the development of a simulation tool to serve both as a training tool for plant operators and as an engineering test-bed to evaluate new equipment and operating strategies (normal operation, cold shut down and others). The development and implementation of the model allows us to estimate the activity transport or "radiation fields" around the primary loop and the vessel, as a function of the operating parameters and the water chemistry.

  15. Electrochemistry of Water-Cooled Nuclear Reactors

    International Nuclear Information System (INIS)

    This project developed a comprehensive mathematical and simulation model for calculating thermal hydraulic, electrochemical, and corrosion parameters, viz. temperature, fluid flow velocity, pH, corrosion potential, hydrogen injection, oxygen contamination, stress corrosion cracking, crack growth rate, and other important quantities in the coolant circuits of water-cooled nuclear power plants, including both Boiling Water Reactors (BWRs) and Pressurized Water Reactors (PWRs). The model is being used to assess the three major operational problems in Pressurized Water Reactors (PWR), which include mass transport, activity transport, and the axial offset anomaly, and provide a powerful tool for predicting the accumulation of SCC damage in BWR primary coolant circuits as a function of operating history. Another achievement of the project is the development of a simulation tool to serve both as a training tool for plant operators and as an engineering test-bed to evaluate new equipment and operating strategies (normal operation, cold shut down and others). The development and implementation of the model allows us to estimate the activity transport or ''radiation fields'' around the primary loop and the vessel, as a function of the operating parameters and the water chemistry

  16. Reuso de efluentes em torres de resfriamento - estudo conceitual: Aeroporto Internacional do Rio de Janeiro - doi: 10.4025/actascitechnol.v32i3.865 Water reuse for cooling towers – conceptual study: Rio de Janeiro International Airport - doi: 10.4025/actascitechnol.v32i3.865

    Directory of Open Access Journals (Sweden)

    Bernardo José Farah Machado

    2010-11-01

    Full Text Available O reuso de água é ferramenta valiosa na gestão da água, que promove a otimização da utilização do recurso desta, que reduz e, muitas vezes, até elimina os impactos no meio ambiente. Neste trabalho foi investigada a composição do efluente secundário da estação de tratamento de efluentes (ETE APOIO do Aeroporto Internacional do Rio de Janeiro, com o objetivo de propor o processo adequado à reutilização deste efluente como água de reposição nas torres de resfriamento desse Aeroporto. Com base nas análises de cátions, ânions, DBO e DQO, verificou-se o parâmetro SDT – Cl- como crítico para processamento do efluente. Foi proposta uma sequência para reutilização do efluente que continha o tratamento de osmose inversa, o custo do m3 produzido por essa sequência foi estimado em R$ 2,90 m-3.Water reuse is an important tool in water management; it is a concept that promotes optimization of the water resource, reducing and often even eliminating environmental impacts. In this work, the composition of a secondary effluent (from the effluent treatment station (ETE APOIO at Rio de Janeiro International Airport was analyzed, with the aim of determining an adequate process for the reutilization of this effluent as replacement cooling water. Chemical analyses such as cation and anion analysis, BOD and COD were performed. Based on these analyses, it was found that TDS – Cl- was the critical parameter for effluent processing. A treatment system was proposed for effluent reuse including reverse osmosis; the cost estimate per m3 produced by this system was R$ 2.90 m-3.

  17. An evaluation of fish behavior upstream of the water temperature control tower at Cougar Dam, Oregon, using acoustic cameras, 2013

    Science.gov (United States)

    Adams, Noah S.; Smith, Collin; Plumb, John M.; Hansen, Gabriel S.; Beeman, John W.

    2015-01-01

    This report describes the initial year of a 2-year study to determine the feasibility of using acoustic cameras to monitor fish movements to help inform decisions about fish passage at Cougar Dam near Springfield, Oregon. Specifically, we used acoustic cameras to measure fish presence, travel speed, and direction adjacent to the water temperature control tower in the forebay of Cougar Dam during the spring (May, June, and July) and fall (September, October, and November) of 2013. Cougar Dam is a high-head flood-control dam, and the water temperature control tower enables depth-specific water withdrawals to facilitate adjustment of water temperatures released downstream of the dam. The acoustic cameras were positioned at the upstream entrance of the tower to monitor free-ranging subyearling and yearling-size juvenile Chinook Salmon (Oncorhynchus tshawytscha). Because of the large size discrepancy, we could distinguish juvenile Chinook salmon from their predators, which enabled us to measure predators and prey in areas adjacent to the entrance of the tower. We used linear models to quantify and assess operational and environmental factors—such as time of day, discharge, and water temperature—that may influence juvenile Chinook Salmon movements within the beam of the acoustic cameras. Although extensive milling behavior of fish near the structure may have masked directed movement of fish and added unpredictability to fish movement models, the acoustic-camera technology enabled us to ascertain the general behavior of discrete size classes of fish. Fish travel speed, direction of travel, and counts of fish moving toward the water temperature control tower primarily were influenced by the amount of water being discharged through the dam.

  18. Experimental study of swirl flow patterns in Gas Conditioning Tower at various entry conditions

    DEFF Research Database (Denmark)

    Jinov, Andrei A.; Larsen, Poul Scheel

    1999-01-01

    In a gas conditioning tower hot flue gas with relatively high dust loads is cooled by injecting water spray near the top. For satisfactory operation wet particles should be kept off walls and all water should have evaporated to yield a uniformly cooled flow before it reaches the bottom of the tower. For practical reasons and space limitations the gas often enters through an inlet pipe making a 150-180° bend shortly before a short diffuser expanding to full tower diameter (Fig. 1). A swirl genera...

  19. Basic regulations and standards for and performance of measurements in wet cooling towers; Norm-Grundlagen und praktische Durchfuehrung von Leistungsmessungen an Nasskuehltuermen

    Energy Technology Data Exchange (ETDEWEB)

    Tesche, W. [Balcke-Duerr GmbH, Ratingen (Germany). Geschaeftsbereich Nasskuehlung

    1998-09-01

    Performance measurement in wet cooling towers is a process well covered and specified by national standards, which meanwhile have been harmonized. The European standard recently eleaborated by the cooling tower manufacturing firms that are members of the VDMA association reflects the state of the art and presents a regulatory framework for applications that has been well tuned to conditions met in practice. Evaluation of measurements relies on a comparative analysis of measured data with the cooling characteristics supplied by the manufacturer, either in the form of a diagram, a computer program, or as tabulated information. (orig./CB) [Deutsch] Leistungsmessungen am Nasskuehlturm sind in laenderspezifischen Normen genau spezifiziert. Die Normen haben sich mittlerweile angeglichen. Die von dem im VDMA zusammengeschlossenen Kuehlturmfirmen erarbeitete Euronorm zu diesem Thema spiegelt den aktuellen Stand in einer praxisnahen Durchfuehrungsverordnung wieder. Die Bewertung der Messung erfolgt im Vergleich mit der vor Messbeginn bekannten Kuehlcharakteristik, die entweder als Diagramm, Rechenprogramm oder zumindest als Tabelle vom Lieferanten erstellt wurde. (orig./GL)

  20. Deposit control in process cooling water systems

    International Nuclear Information System (INIS)

    In order to achieve efficient heat transfer in cooling water systems, it is essential to control the fouling of heat exchanger surfaces. Solubilities of scale forming salts, their growth into crystals, and the nature of the surfaces play important roles in the deposition phenomenon. Condensed phosphates, organic polymers and compounds like phosphates are effective in controlling deposition of scale forming salts. The surface active agents inhibit crystal growth and modify the crystals of the scale forming salts, and thus prevent deposition of dense, uniformly structured crystalline mass on the heat transfer surface. Understanding the mechanism of biofouling is essential to control it by surface active agents. Certain measures taken in the plant, such as back flushing, to control scaling, sometimes may not be effective and can be detrimental to the system itself. (author)

  1. Heavy water moderated gas-cooled reactors

    International Nuclear Information System (INIS)

    France has based its main effort for the production of nuclear energy on natural Uranium Graphite-moderated gas-cooled reactors, and has a long term programme for fast reactors, but this country is also engaged in the development of heavy water moderated gas-cooled reactors which appear to present the best middle term prospects. The economy of these reactors, as in the case of Graphite, arises from the use of natural or very slightly enriched Uranium; heavy water can take the best advantages of this fuel cycle and moreover offers considerable development potential because of better reactor performances. A prototype plant EL 4 (70 MW) is under construction and is described in detail in another paper. The present one deals with the programme devoted to the development of this reactor type in France. Reasons for selecting this reactor type are given in the first part: advantages and difficulties are underlined. After reviewing the main technological problems and the Research and Development carried out, results already obtained and points still to be confirmed are reported. The construction of EL 4 is an important step of this programme: it will be a significant demonstration of reactor performances and will afford many experimentation opportunities. Now the design of large power reactors is to be considered. Extension and improvements of the mechanical structures used for EL 4 are under study, as well as alternative concepts. The paper gives some data for a large reactor in the present state of technology, as a result from optimization studies. Technical improvements, especially in the field of materials could lead to even more interesting performances. Some prospects are mentioned for the long run. Investment costs and fuel cycles are discussed in the last part. (authors)

  2. Surface protection of inner shells of cooling towers. Positive long-term experience with coating systems.; Oberflaechenschutz von Kuehlturminnenschalen. Positive Langzeiterfahrungen mit Beschichtungssystemen

    Energy Technology Data Exchange (ETDEWEB)

    Heine, Peer [MC-Bauchemie Mueller GmbH und Co.KG, Bottrop (Germany)

    2010-07-15

    Natural-draught cooling tower are modern power plant components with great importance for safe and reliable power supply. Due to the complex effects of operating and environmental conditions especially on the inner shell, the concrete must be protected by special resin-based surface coating systems. Parallel to the development of the power plant technology, also the coating systems are under constant improvement in order to ensure reliable and permanent protection. The positive long-term experience suggests that power plant operators may rely on a high level of safety here. (orig.)

  3. The role of water in cooling ignimbrites

    Science.gov (United States)

    Keating, Gordon N.

    2005-04-01

    A summary of observational literature on ignimbrites provides the basis for the development of a two-dimensional numerical model of ignimbrite cooling processes. Factors include emplacement conditions, post-emplacement processes, and the nature and timing of interactions with water during cooling. The model uses the multiphase finite element heat and mass transfer (FEHM) code, which has been enhanced to handle conditions up to 1500 °C. The instantaneous emplacement of a 750 °C ignimbrite with internal gas pressures of up to 0.5 MPa (lithostatic) has a great effect on the variably saturated substrate. A water table present within a few tens of meters of the base of the ignimbrite produces a region of high pressure and temperature that exists for about 20 years, driving vapor upward through the ignimbrite as diffuse flow and in gas escape structures and enhancing cooling at the base of the ignimbrite. Variations in initial gas pressure between atmospheric and lithostatic conditions have little effect on the thermal evolution. The results of the numerical modeling of 20- and 40-m-thick ignimbrites indicate that, even for moderate pore water saturations in the substrate, vaporization and resultant pressurization may exceed lithostatic confining pressures in the upper substrate and basal ignimbrite, and explosive pressure release may occur, resulting in the development of discrete fumarole conduits or phreatic explosions. The likelihood for explosive pressure release appears to be greater when the nominal ignimbrite thickness is on the order of the depth of a buried valley. The pressure buildup is enhanced by the geometry of the ignimbrite-substrate interface, especially at convex corners such as on the edges of a buried valley. The boiling zones at the top and bottom of a cooling ignimbrite involve the development of a heat-pipe, which provides an efficient means of transporting heat from the superheated tephra out tens of meters into the ambient environment. The predicted temporal evolution of temperature, pressure, and vapor flow in a 40-m ignimbrite support the conceptual model of degassing, welding and compaction, devitrification, and alteration occurring concomitantly in the first several years after emplacement and driven in part by production and migration of meteoric steam. This vapor flowing through the ignimbrite matrix at 5×10 -5 kg s -1 in the first 10 years enhances devitrification in any part of the ignimbrite above the base in nonwelded deposits. In the case where welding occurs, lower permeability limits the diffuse flow of gas upward through the ignimbrite from the region of boiling and pore pressurization at the base, and enhanced devitrification in the basal parts of the ignimbrite may occur where pore vapors circulate in abundance. Immediately above the welded zone, a devitrified horizon may develop where the upper boiling/condensation zone and perched meteoric infiltration results in enhanced saturations.

  4. Process and device for removing radio-active waste water

    International Nuclear Information System (INIS)

    The waste water is treated by one or several evaporation processes, chemical precipitation or filtering. The waste water treated in this way is then evaporated in a dry cooling tower of a PWR or gas cooled high temperature reactor. (DG)

  5. Technical analysis of a river basin-based model of advanced power plant cooling technologies for mitigating water management challenges

    Science.gov (United States)

    Stillwell, Ashlynn S.; Clayton, Mary E.; Webber, Michael E.

    2011-07-01

    Thermoelectric power plants require large volumes of water for cooling, which can introduce drought vulnerability and compete with other water needs. Alternative cooling technologies, such as cooling towers and hybrid wet-dry or dry cooling, present opportunities to reduce water diversions. This case study uses a custom, geographically resolved river basin-based model for eleven river basins in the state of Texas (the Brazos and San Jacinto-Brazos, Colorado and Colorado-Brazos, Cypress, Neches, Nueces, Red, Sabine, San Jacinto, and Trinity River basins), focusing on the Brazos River basin, to analyze water availability during drought. We utilized two existing water availability models for our analysis: (1) the full execution of water rights—a scenario where each water rights holder diverts the full permitted volume with zero return flow, and (2) current conditions—a scenario reflecting actual diversions with associated return flows. Our model results show that switching the cooling technologies at power plants in the eleven analyzed river basins to less water-intensive alternative designs can potentially reduce annual water diversions by 247-703 million m3—enough water for 1.3-3.6 million people annually. We consider these results in a geographic context using geographic information system tools and then analyze volume reliability, which is a policymaker's metric that indicates the percentage of total demand actually supplied over a given period. This geographic and volume reliability analysis serves as a measure of drought susceptibility in response to changes in thermoelectric cooling technologies. While these water diversion savings do not alleviate all reliability concerns, the additional streamflow from the use of dry cooling alleviates drought concerns for some municipal water rights holders and might also be sufficient to uphold instream flow requirements for important bays and estuaries on the Texas Gulf coast.

  6. Technical analysis of a river basin-based model of advanced power plant cooling technologies for mitigating water management challenges

    International Nuclear Information System (INIS)

    Thermoelectric power plants require large volumes of water for cooling, which can introduce drought vulnerability and compete with other water needs. Alternative cooling technologies, such as cooling towers and hybrid wet-dry or dry cooling, present opportunities to reduce water diversions. This case study uses a custom, geographically resolved river basin-based model for eleven river basins in the state of Texas (the Brazos and San Jacinto-Brazos, Colorado and Colorado-Brazos, Cypress, Neches, Nueces, Red, Sabine, San Jacinto, and Trinity River basins), focusing on the Brazos River basin, to analyze water availability during drought. We utilized two existing water availability models for our analysis: (1) the full execution of water rights-a scenario where each water rights holder diverts the full permitted volume with zero return flow, and (2) current conditions-a scenario reflecting actual diversions with associated return flows. Our model results show that switching the cooling technologies at power plants in the eleven analyzed river basins to less water-intensive alternative designs can potentially reduce annual water diversions by 247-703 million m3-enough water for 1.3-3.6 million people annually. We consider these results in a geographic context using geographic information system tools and then analyze volume reliability, which is a policymaker's metric that indicates the percentage of total demand actually supplied over a given period. This geographic and volume reliability analysis serves as a measure of drought susceptibility in response to changes in thermoelectric cooling technologies. While these water diversion savings do not alleviate all reliability concerns, the additional streamflow from the use of dry cooling alleviates drought concerns for some municipal water rights holders and might also be sufficient to uphold instream flow requirements for important bays and estuaries on the Texas Gulf coast.

  7. WGOTHIC analysis of AP1000 passive containment cooling water

    International Nuclear Information System (INIS)

    The WGOTHIC code was used to analyze the influence of the containment cooling water inventory to containment safety for different cases. The results show that if passive containment cooling system fails, the pressure in containment is beyond design limit after 1000 s; if cooling water can't be supplied after 72 h, the pressure in containment is beyond design limit after 0.9 d; if cooling water can't be supplied after 19.6 d, the pressure in containment is beyond design limit but less than the breakdown pressure; if cooling water is supplied for 30 d, the air cooling can remove the decay heat without any aid. It is a reference for making emergency plan and improving containment design. (authors)

  8. Equipment cooling system and sea water cooling system in the after-heat removal system

    International Nuclear Information System (INIS)

    Purpose: To improve the reliability of an emergency diesel generator in the after-heat removal system and of pumps for the equipment cooling system and the sea water cooling system, as well as improve the reliability of the after-heat removal system upon accident to thereby facilitate the cooling for a long time. Constitution: The after-heat removal system of a BWR type reactor actuated upon accident comprises each two equipment cooling systems and sea water cooling systems. For each of the two systems of the equipment cooling system and the sea water cooling system in the after-heat removal system, are provided pipeways for connecting the upstream side of the pumps, pipeways for connecting the downstream sides of the pumps, a pump equipped with an emergency diesel generator independent from the two systems connected with the pipeways and check valves provided at the upstream and the downstream of the pumps. These equipments are controlled in accordance with low pressure water injection mode, reactor container spray mode, pool water cooling mode, steam condensation mode and shutdown cooling mode. (Aizawa, K.)

  9. Ozonation of cooling water prevents biofilms and legionella. Hygiene; Kuehlwasserbehandlung mit Ozon haelt Biofilme und Legionellen in Schach. Hygiene

    Energy Technology Data Exchange (ETDEWEB)

    Hackl, W.; Hoffmann, M. [BWT Wassertechnik GmbH, Schriesheim (Germany). Forschung und Entwicklung

    2006-11-15

    Legionella in plumes of evaporation cooling towers have often caused serious illnesses and even deaths. To prevent the growth of microorganisms in cooling towers, operators often use hazardous and toxic biocides or chlorine. There is an ecologically and also technically efficient alternative: In the Briey plant of the international Norma group, biofilm and legionella prophylaxis is achieved by ozonation. (orig.)

  10. Validation of the kinetic model for predicting the composition of chlorinated water discharged from power plant cooling systems

    International Nuclear Information System (INIS)

    The purpose of this report is to present a validation of a previously described kinetic model which was developed to predict the composition of chlorinated fresh water discharged from power plant cooling systems. The model was programmed in two versions: as a stand-alone program and as a part of a unified transport model developed from consistent mathematical models to simulate the dispersion of heated water and radioisotopic and chemical effluents from power plant discharges. The results of testing the model using analytical data taken during operation of the once-through cooling system of the Quad Cities Nuclear Station are described. Calculations are also presented on the Three Mile Island Nuclear Station which uses cooling towers

  11. New structural design standard for cooling towers. Pilot project BoA 2 and 3 in Neurath; Pilotprojekt der neuen Normengeneration im Kuehlturmbau. Die Naturzugkuehltuerme von BoA 2 and 3 in Neurath

    Energy Technology Data Exchange (ETDEWEB)

    Woermann, Ralf [Kraetzig und Partner Ingenieurgesellschaft fuer Bautechnik mbH, Bochum (Germany); Haupt, Ralf [ALPINE BAU DEUTSCHLAND AG NL Industrie- und Kraftwerksbau, Dortmund (Germany); Ohlmann, Uwe [RWE Power AG, Essen (Germany). Bautechnik

    2010-01-15

    Starting in 2006 RWE Power is erecting two lignite power plants with highly optimized efficiency (BoA) in Neurath near Cologne. These will be the second and third plant of this most advanced technique after the completion of BoA1 in Niederaussem in 2003. The most outstanding buildings of the new power-station are the natural draught cooling towers with a height of 173 m. Their design and execution will be described in this paper. For the first time in cooling tower design the completely revised new edition 2005 of the VGB-Guideline ''Structural Design of Cooling Towers'' was applied in connection with other related new design standards. (orig.)

  12. Technology for Water Treatment (National Water Management)

    Science.gov (United States)

    1992-01-01

    The buildup of scale and corrosion is the most costly maintenance problem in cooling tower operation. Jet Propulsion Laboratory successfully developed a non-chemical system that not only curbed scale and corrosion, but also offered advantages in water conservation, cost savings and the elimination of toxic chemical discharge. In the system, ozone is produced by an on-site generator and introduced to the cooling tower water. Organic impurities are oxidized, and the dissolved ozone removes bacteria and scale. National Water Management, a NASA licensee, has installed its ozone advantage systems at some 200 cooling towers. Customers have saved money and eliminated chemical storage and discharge.

  13. Study on water cooled high conversion reactor

    Energy Technology Data Exchange (ETDEWEB)

    Ochiai, Masaaki [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1999-12-01

    As a part of study on advanced reactors for the future, conceptual design of high conversion water cooled reactors is being studied, aiming at the contribution to nuclear fuel cycle by the LWR technology, since the utilization of LWRs will extend over a long period of time . We are studying on the reactor core concepts for BWR and PWR reactor systems. As for BWR system, three types of reactor cores are investigating for three different design goals; long operation period, high conversion ratio and high applicability for the existing BWR system. In all the cases, we have obtained a fair prospect of a large core concept with a capacity of 1,000 MWe class having negative void reactivity coefficient. This study is a part of JAERI-JAPCO (Japan Atomic Power Company) cooperative studies. Various kinds of conceptual designs will be created until the end of FY 1999. The designs will be checked and reviewed at that time, then experimental studies on the realization of the concepts will start with further design works from FY 2000. (author)

  14. Controlled Cooling of Hot Rolled Steel Channels by Water Spraying on the Final Cooling Bed

    OpenAIRE

    Srinivas Rachamadagu; Malur Srinivasan

    2013-01-01

    The objective of this research is to design an effective and relatively simple method for controlled cooling of hot rolled steel channels by water spraying on the final cooling bed after continuous cast steel billets passing through reheating furnace and sequential rolls to form channels. The need for this research arose as the channels were being cooled by forced air draft and natural convection which brought the temperature of the channels to about 270°C (518°F) at the shear stand. Ste...

  15. Water cooled reactor technology: Safety research abstracts no. 1

    International Nuclear Information System (INIS)

    The Commission of the European Communities, the International Atomic Energy Agency and the Nuclear Energy Agency of the OECD publish these Nuclear Safety Research Abstracts within the framework of their efforts to enhance the safety of nuclear power plants and to promote the exchange of research information. The abstracts are of nuclear safety related research projects for: pressurized light water cooled and moderated reactors (PWRs); boiling light water cooled and moderated reactors (BWRs); light water cooled and graphite moderated reactors (LWGRs); pressurized heavy water cooled and moderated reactors (PHWRs); gas cooled graphite moderated reactors (GCRs). Abstracts of nuclear safety research projects for fast breeder reactors are published independently by the Nuclear Energy Agency of the OECD and are not included in this joint publication. The intention of the collaborating international organizations is to publish such a document biannually. Work has been undertaken to develop a common computerized system with on-line access to the stored information

  16. Assessing MODIS GPP in Non-Forested Biomes in Water Limited Areas Using EC Tower Data

    Directory of Open Access Journals (Sweden)

    Flor Álvarez-Taboada

    2015-03-01

    Full Text Available Although shrublands, savannas and grasslands account for 37% of the world’s terrestrial area, not many studies have analysed the role of these ecosystems in the global carbon cycle at a regional scale. The MODIS Gross Primary Production (GPP product is used here to help bridge this gap. In this study, the agreement between the MODIS GPP product (GPPm and the GPP Eddy Covariance tower data (GPPec was tested for six different sites in temperate and dry climatic regions (three grasslands, two shrublands and one evergreen forest. Results of this study show that for the non-forest sites in water-limited areas, GPPm is well correlated with GPPec at annual scales (r2 = 0.77, n = 12; SEE = 149.26 g C?m?2?year?1, although it tends to overestimate GPP and it is less accurate in the sites with permanent water restrictions. The use of biome-specific models based on precipitation measurements at a finer spatial resolution than the Data Assimilation Office (DAO values can increase the accuracy of these estimations. The seasonal dynamics and the beginning and end of the growing season were well captured by GPPm for the sites where (i the productivity was low throughout the year or (ii the changes in the flux trend were abrupt, usually due to the restrictions in water availability. The agreement between GPPec and GPPm in non-forested sites was lower on a weekly basis than at an annual scale (0.44 ? r2 ? 0.49, but these results were improved by including meteorological data at a finer spatial scale, and soil water content and temperature measurements in the model developed to predict GPPec (0.52 ? r2 ? 0.65.

  17. Operating manual for the Tower Shielding Facility

    International Nuclear Information System (INIS)

    This manual provides information necessary to operate and perform maintenance on the reactor systems and all equipment or systems which can affect their operation or the safety of personnel at the Tower Shielding Facility. The first four chapters consist of introductory and descriptive material of benefit to personnel in training, the qualifications required for training, the responsibilities of the personnel in the organization, and the procedures for reviewing proposed experiments. Chapter 8, Emergency Procedures, is also a necessary part of the indoctrination of personnel. The procedures for operation of the Tower Shielding Reactor (TSR-II), its water cooling system, and the main tower hoists are outlined in Chapters 5, 6, and 7. The Technical Specification surveillance requirements for the TSR-II are summarized in Chapter 9. The maintenance and calibration schedule is spelled out in Chapter 10. The procedures for assembly and disassembly of the TSR-II are outlined in Chapter 11

  18. 77 FR 73056 - Initial Test Programs for Water-Cooled Nuclear Power Plants

    Science.gov (United States)

    2012-12-07

    ...Programs for Water-Cooled Nuclear Power Plants AGENCY: Nuclear Regulatory...Programs for Water-Cooled Nuclear Power Plants.'' This guide describes...ITPs) for light water cooled nuclear power plants. DATES: Submit comments...

  19. 78 FR 35330 - Initial Test Programs for Water-Cooled Nuclear Power Plants

    Science.gov (United States)

    2013-06-12

    ...Programs for Water-Cooled Nuclear Power Plants AGENCY: Nuclear Regulatory...Programs for Water-Cooled Nuclear Power Plants.'' This guide describes...ITPs) for light water cooled nuclear power plants. ADDRESSES: Please...

  20. Naegleria fowleri in cooling waters of power plants.

    Science.gov (United States)

    Cerva, L; Kasprzak, W; Mazur, T

    1982-01-01

    Six strains of nonvirulent and three strains of virulent variants of Naegleria fowleri amoebae were isolated from the examined cooling water samples from 9 power plants. The virulent variants were obtained solely from effluents discharged from power plants with a closed-circuit cooling N. fowleri was not detected outside the reach of the thermal pollution. A disinfection of out-flowing cooling water seems to be an unnecessary investment in our climate. Warm discharge water should under no conditions be used directly for sports and recreational purposes. PMID:7119430

  1. Use of Produced Water in Recirculated Cooling Systems at Power Generating Facilities

    Energy Technology Data Exchange (ETDEWEB)

    C. McGowin; M. DiFilippo; L. Weintraub

    2006-06-30

    Tree ring studies indicate that, for the greater part of the last three decades, New Mexico has been relatively 'wet' compared to the long-term historical norm. However, during the last several years, New Mexico has experienced a severe drought. Some researchers are predicting a return of very dry weather over the next 30 to 40 years. Concern over the drought has spurred interest in evaluating the use of otherwise unusable saline waters to supplement current fresh water supplies for power plant operation and cooling and other uses. The U.S. Department of Energy's National Energy Technology Laboratory sponsored three related assessments of water supplies in the San Juan Basin area of the four-corner intersection of Utah, Colorado, Arizona, and New Mexico. These were (1) an assessment of using water produced with oil and gas as a supplemental supply for the San Juan Generating Station (SJGS); (2) a field evaluation of the wet-surface air cooling (WSAC) system at SJGS; and (3) the development of a ZeroNet systems analysis module and an application of the Watershed Risk Management Framework (WARMF) to evaluate a range of water shortage management plans. The study of the possible use of produced water at SJGS showed that produce water must be treated to justify its use in any reasonable quantity at SJGS. The study identified produced water volume and quality, the infrastructure needed to deliver it to SJGS, treatment requirements, and delivery and treatment economics. A number of produced water treatment alternatives that use off-the-shelf technology were evaluated along with the equipment needed for water treatment at SJGS. Wet surface air-cooling (WSAC) technology was tested at the San Juan Generating Station (SJGS) to determine its capacity to cool power plant circulating water using degraded water. WSAC is a commercial cooling technology and has been used for many years to cool and/or condense process fluids. The purpose of the pilot test was to determine if WSAC technology could cool process water at cycles of concentration considered highly scale forming for mechanical draft cooling towers. At the completion of testing, there was no visible scale on the heat transfer surfaces and cooling was sustained throughout the test period. The application of the WARMF decision framework to the San Juan Basis showed that drought and increased temperature impact water availability for all sectors (agriculture, energy, municipal, industry) and lead to critical shortages. WARMF-ZeroNet, as part of the integrated ZeroNet decision support system, offers stakeholders an integrated approach to long-term water management that balances competing needs of existing water users and economic growth under the constraints of limited supply and potential climate change.

  2. The influence of Savannah River discharge and changing SRS cooling water requirements on the potential entrainment of ichthyoplankton at the SRS Savannah River intakes

    International Nuclear Information System (INIS)

    Entrainment (i.e., withdrawal of fish larvae and eggs in cooling water) at the SRS Savannah River intakes is greatest when periods of high river water usage coincide with low river dischargeduring the spawning season. American shad and striped bass are the two species of greatest concern because of their recreational and/or commercial importance and because they produce drifting eggs and larvae vulnerable to entrainment. In the mid-reaches of the Savannah River, American shad and striped bass spawn primarily during April and May. An analysis of Savannah River discharge during April and May 1973--1989 indicated the potential for entrainment of 4--18% of the American shad and striped bass larvae and eggs that drifted past the SRS. This analysis assumed the concurrent operation of L-, K-, and P-Reactors. Additional scenarios investigated were: (1) shutting down L- and P-Reactors, and operating K-Reactor with a recycle cooling tower; and (2) shutting down L- and P-Reactors, eliminating minimum flows to Steel Creek, and operating K-Reactor with a recycle cooling tower. The former scenario reduced potential entrainment to 0.7--3.3%, and the latter scenario reduced potential entrainment to 0.20.8%. Thus, the currently favored scenario of operating K-Reactor with a cooling tower and not operating L- and P-Reactors represents a significant lessening of the impact of SRS operations

  3. Thermodynamic analysis of cooling systems for nuclear power stations condenser

    International Nuclear Information System (INIS)

    This work is an attempt to concentrate on the thermodynamic theory, the engineering solution and the quantities of water needed for the operation of a wet as well as a wet/dry cooling towers coupled to a nuclear turbine condenser,. About two hundred variables are needed for the design of a condenser - cooling tower system. In order to make the solution fast and handy, a computer model was developed. The amount of water evaporation from cooling towers is a function of the climate conditions prevailing around the site. To achieve an authentic analysis, the meteorological data of the northern Negev was used. The total amount of water necessary to add to the system in a year time of operation is large and is a function of both the blow-down rate and the evaporation. First estimations show that the use of a combined system, wet/dry cooling tower, is beneficial in the northern Negev area. Such a system can reduce significantly the amount of wasted fresh water. Lack of international experience is the major problem in the acceptability of wet/dry cooling towers. The technology of a wet cooling tower using sea water is also discussed where no technical or engineering limitations were found. This work is an attempt to give some handy tools for making the choice of cooling systems for nuclear power plants easier

  4. Hydraulic problems in cooling water recirculating systems of nuclear power plants

    International Nuclear Information System (INIS)

    Hydraulic design problems of the structures in the free-surface part of the recirculating system (intake and distribution structure, control weir, cooling tower) are described. The capacity of the cooling system required for realization of once-through cooling, blow-down, recirculation and mixed mode operation is discussed, and experimental and numerical methods of solution are illustrated by means of several representative investigations of existing and planned installations. (orig.)

  5. Evaluation of cooling water treatment programme at RAPS-3 and 4 with reference to chlorination and microbial control

    International Nuclear Information System (INIS)

    Water from Rana Pratap Sagar Lake is used in Rajasthan Atomic Power Station (RAPS) units 3 and 4 for cooling the condenser system. As the lake water is rich in nutrients and microflora, investigations were carried out on the nutrient quality, microflora distribution and chlorine decay to evaluate the cooling water treatment programme. Algal growth in emergency storage makeup water pools, weed growth on the cooling tower decks and biofilm growth on various materials (carbon steel, stainless steel, admiralty brass and cupronickel) were studied with an objective to understand the reasons for corrosion and failure of fire water pipeline. Visual examination showed that the emergency makeup water pools were infested with green algae and cyano-bacterial mats. Some algal growth was observed on induced draft cooling tower-3 structures. The bacterial counts in various water samples were low, except in emergency makeup water pool. Sulphate reducing bacteria (SRB) were present in makeup and demineralised waters. Chlorophyll pigment analysis showed that the makeup and emergency storage water pool had abundant algal growth. To prevent biofouling, chlorine is dosed at the rate of 7 kg/hr for 10 minutes; free residual oxidant (FRO) and chlorine decay were monitored at regular intervals. After 24 hrs, biofilm thickness on different materials ranged from 27-45 ?m. However, the thickness was reduced by 50 % after exposure to 2 ppm of chlorine for 15 minutes. In further investigations, it was found that the anion resin beads of demineraliser plant were infested with filamentous microbes. Hence, It is recommended to treat the feed water of DM plant. Tubercles were observed inside the failed fire water carbon steel pipeline and on removing the tubercles concentric ring patterns, typical signatures of SRB corrosion were observed. For controlling the biofouling problem in the cooling water system, it is recommended to maintain a chlorine dose of 2.3 ppm (which gives 0.8 ppm FRO) for two hours in every shift. To control the algal growth in the emergency storage water pools, it is recommended to dose 4.0 ppm of sodium hypochlorite on alternate days. (author)

  6. The meteorological measuring system of the Karlsruhe Nuclear Research Centre - evaluation of special measurements to determine the seasonal and daily distribution of long cooling tower plumes

    International Nuclear Information System (INIS)

    The measuring system mainly serves to record the parameters which are relevant for the diffusion of off-gas plumes and it comprises a total of 47 instruments allowing to measure the wind velocity, wind direction, wind vector, temperature, dew point, global and thermal radiation, precipitation, and atmospheric pressure. An account is given of the methods of measurement, measurement accuracy and operating experience gathered during several years. As an example of the versatile application of the data stored a statistical evaluation of humidity conditions is performed taking into account the length of visible cooling tower plumes. Work concentrates on the representation of the seasonal and daily distribution of situations during which the visible plumes get longer than 2.5 km. (orig.)

  7. Cooling performance of helium-gas/water coolers in HENDEL

    International Nuclear Information System (INIS)

    The helium engineering demonstration loop (HENDEL) has four helium-gas/water coolers where the cooling water flows in the tubes and helium gas on the shell side. Their cooling performance was studied using the operational data from 1982 to 1991. The heat transfer of helium gas on the shell was obtained for segmental and step-up baffle type coolers. Also, the change with operation time was investigated. The cooling performance was lowered by the graphite powder released from the graphite components for several thousand hours and thereafter recovered because the graphite powder from the components was reduced and the powder in the cooler shell was blown off during the operation. (orig.)

  8. Cooling water intakes utilizing Ranney Collectors or Ranney Intakes

    International Nuclear Information System (INIS)

    Minimization of the loss of aquatic biota is a major factor in the location, design, construction, and capacity of cooling water intake structures. In a comprehensive report, the U.S. Environmental Protection Agency (1976) has reviewed the present methods and technology available for minimizing adverse environmental impact of cooling water intakes. Two types of intakes, described in the report and classified as non-conventional intakes, are discussed in this paper: the Ranney Collector, which is a subsurface intake utilizing natural sand and gravel deposits to transmit water from a surface source, and the Ranney Surface Water Intake, which is a submerged, horizontal perforated-pipe intake

  9. DUSEL Facility Cooling Water Scaling Issues

    Energy Technology Data Exchange (ETDEWEB)

    Daily, W D

    2011-04-05

    Precipitation (crystal growth) in supersaturated solutions is governed by both kenetic and thermodynamic processes. This is an important and evolving field of research, especially for the petroleum industry. There are several types of precipitates including sulfate compounds (ie. barium sulfate) and calcium compounds (ie. calcium carbonate). The chemical makeup of the mine water has relatively large concentrations of sulfate as compared to calcium, so we may expect that sulfate type reactions. The kinetics of calcium sulfate dihydrate (CaSO4 {center_dot} 2H20, gypsum) scale formation on heat exchanger surfaces from aqueous solutions has been studied by a highly reproducible technique. It has been found that gypsum scale formation takes place directly on the surface of the heat exchanger without any bulk or spontaneous precipitation in the reaction cell. The kinetic data also indicate that the rate of scale formation is a function of surface area and the metallurgy of the heat exchanger. As we don't have detailed information about the heat exchanger, we can only infer that this will be an issue for us. Supersaturations of various compounds are affected differently by temperature, pressure and pH. Pressure has only a slight affect on the solubility, whereas temperature is a much more sensitive parameter (Figure 1). The affect of temperature is reversed for calcium carbonate and barium sulfate solubilities. As temperature increases, barium sulfate solubility concentrations increase and scaling decreases. For calcium carbonate, the scaling tendencies increase with increasing temperature. This is all relative, as the temperatures and pressures of the referenced experiments range from 122 to 356 F. Their pressures range from 200 to 4000 psi. Because the cooling water system isn't likely to see pressures above 200 psi, it's unclear if this pressure/scaling relationship will be significant or even apparent. The most common scale minerals found in the oilfield include calcium carbonates (CaCO3, mainly calcite) and alkaline-earth metal sulfates (barite BaSO4, celestite SrSO4, anhydrite CaSO4, hemihydrate CaSO4 1/2H2O, and gypsum CaSO4 2H2O or calcium sulfate). The cause of scaling can be difficult to identify in real oil and gas wells. However, pressure and temperature changes during the flow of fluids are primary reasons for the formation of carbonate scales, because the escape of CO2 and/or H2S gases out of the brine solution, as pressure is lowered, tends to elevate the pH of the brine and result in super-saturation with respect to carbonates. Concerning sulfate scales, the common cause is commingling of different sources of brines either due to breakthrough of injected incompatible waters or mixing of two different brines from different zones of the reservoir formation. A decrease in temperature tends to cause barite to precipitate, opposite of calcite. In addition, pressure drops tend to cause all scale minerals to precipitate due to the pressure dependence of the solubility product. And we can expect that there will be a pressure drop across the heat exchanger. Weather or not this will be offset by the rise in pressure remains to be seen. It's typically left to field testing to prove out. Progress has been made toward the control and treatment of the scale deposits, although most of the reaction mechanisms are still not well understood. Often the most efficient and economic treatment for scale formation is to apply threshold chemical inhibitors. Threshold scale inhibitors are like catalysts and have inhibition efficiency at very low concentrations (commonly less than a few mg/L), far below the stoichiometric concentrations of the crystal lattice ions in solution. There are many chemical classes of inhibitors and even more brands on the market. Based on the water chemistry it is anticipated that there is a high likelihood for sulfate compound precipitation and scaling. This may be dependent on the temperature and pressure, which vary throughout the system. Therefore, various types and amounts of scaling ma

  10. Water cooling system for sintering furnaces of nuclear fuel pellets

    International Nuclear Information System (INIS)

    This work has as a main objective to develop a continuous cooling water system, which is necessary for the cooling of the sintering furnaces. This system is used to protect them as well as for reducing the water consumption, ejecting the heat generated into this furnaces and scattering it into the atmosphere in a fast and continuous way. The problem was defined and the reference parameters established, making the adequate research. The materials were selected as well as the length of the pipeline which will carry the secondary refrigerant fluid (water). Three possible solutions were tried,and evaluated, and from these, the thermal and economically most efficient option was selected. The layout of the solution was established and the theoretical construction of a cooling system for liquids using dichlorofluoromethane (R-22), as a refrigerant and a air cooled condenser, was accomplished. (Author)

  11. Cooling water conditioning and quality control for tokamaks

    International Nuclear Information System (INIS)

    Designers and operators of Tokamaks and all associated water cooled, peripheral equipment, are faced with the task of providing and maintaining closed-loop, low conductivity, low impurity, cooling water systems. Most of these systems must provide large volumes of high quality cooling water at reasonable cost and comply with local and state government orders and EPA mandated national pretreatment standards and regulations. This paper discusses the DIII-D water quality requirements, the means used to obtain the necessary quality and the instrumentation used for control and monitoring. Costs to mechanically and chemically condition and maintain water quality are discussed as well as the various aspects of complying with government standards and regulations

  12. Auxiliary equipment for cooling water in a reactor

    International Nuclear Information System (INIS)

    Object: To effectively make use of pressure energy of reactor water, which has heretofore been discarded, to enable supply of emergency power supply of high reliability and to prevent spreading of environmental contamination. Structure: Sea water pumped by a sea water supply pump is fed to a heat exchanger. Reactor water carried through piping on the side to be cooled is removed in heat by the heat exchanger to be cooled and returned, and then again returned to the reactor. On the other hand, sea water heated by the heat exchanger is fed to a water wheel to drive the water wheel, after which it is discharged into a discharging path. A generator may be directly connected to the water wheel to use the electricity generated by the generator as the emergency power source. (Kamimura, M.)

  13. Experiences on condenser cooling water treatment programme at NAPS

    International Nuclear Information System (INIS)

    The Narora Atomic Power Station has twin units of 220 MWe pressurized heavy water reactors, situated at the banks of river Ganges in Bulandshahr District of Uttar Pradesh. The plant cooling water takes the make up water supply from river Ganges after pretreatment using polyelectrolyte at two number of clariflocculators. The condenser cooling water system of the station is of open recirculating type and the clarified raw water used as a cooling medium is having a concentration cycle of cooling about 2.0. The calcium concentration in recirculating water is around 160 mg/litre as CaCO3 at full power of the unit. The Langelier Saturation Index of the recirculating water is observed to be in the range + 1.2 to + 1.8, indicating moderately high tendency, towards scale formation on heat transfer surfaces, such as condenser tubes, Turbine lubricating oil coolers and other associated heat exchangers. The condenser cooling water treatment was not envisaged in the original design. Therefore untreated surface water resulting in scale formation (0.3 to 0.5 mm thickness) due to deposition of calcium carbonate was observed in the condenser tubes of NAPS Unit 1 and 2 during initial period of operation (1989 to 1992). It was observed that the scaling on condenser tube surfaces caused increase in terminal temperature difference (TTD) from a design value of 5.5 degC to 13.0 degC. In addition to this a substantial drop in heat transfer coefficient from a value of about 2000 kcal/hr/m2/degC to 1200 kcal/hr/m2/degC occurred. On thorough review actions were initiated at NAPS to restore the heat transfer through condensers. The present paper highlights the experiences on the treatment of cooling water

  14. Study of the cooling characteristics of the water cooling panel system. Pressure vessel without stand pipes

    International Nuclear Information System (INIS)

    Experimental works using the test apparatus of water cooling panel system of Modular High Temperature Gas cooled Reactor were performed to acquire the experimental data of cooling performance and temperature distribution of the components. And also the analytical works were carried out to analyze the experimental data acquired from the three cases of the vacuum, helium gas at 0.73MPa and nitrogen gas at 1.1MPa in the pressure vessel, to verify the validity of two-dimensional analytical code -THANPACST2- to investigate the cooling performance of the water cooling panel system. Conclusions are summarized as follows, (1) In the condition of nitrogen gas, in which maximum temperature of the pressure vessel is 420degC, analytical results of the temperature of the pressure vessel using the emissivity ?p.v=0.80 of the surfaces of the pressure vessel and the cooling panel was estimated within the errors of -18% and +42% compared to the experimental one. The analytical result of heat transferred to the cooling panel was estimated to be 16.4% lower than the experimental result of heat input. (2) It was indicated that natural convection of air in the reactor cavity considerably affected on the temperature distribution of the pressure vessel although only 15-30% of the total heat was transferred by natural convection

  15. Operation and maintenance of the cooling source

    International Nuclear Information System (INIS)

    This paper successively deals with the four main questions pertaining to operation and maintenance of the cooling source in nuclear power stations: treatment of water for cooling, watching for silt in various parts of the cooling circuit and the cleanliness of the condenser, operating and maintenance problems pertaining to the condenser (erosion, corrosion and vibratory fatigue of tubes and solutions developed) and the cooling towers (freezing and freeze protection)

  16. Use of reclaimed water for power plant cooling.

    Energy Technology Data Exchange (ETDEWEB)

    Veil, J. A.; Environmental Science Division

    2007-10-16

    Freshwater demands are steadily increasing throughout the United States. As its population increases, more water is needed for domestic use (drinking, cooking, cleaning, etc.) and to supply power and food. In arid parts of the country, existing freshwater supplies are not able to meet the increasing demands for water. New water users are often forced to look to alternative sources of water to meet their needs. Over the past few years, utilities in many locations, including parts of the country not traditionally water-poor (e.g., Georgia, Maryland, Massachusetts, New York, and North Carolina) have needed to reevaluate the availability of water to meet their cooling needs. This trend will only become more extreme with time. Other trends are likely to increase pressure on freshwater supplies, too. For example, as populations increase, they will require more food. This in turn will likely increase demands for water by the agricultural sector. Another example is the recent increased interest in producing biofuels. Additional water will be required to grow more crops to serve as the raw materials for biofuels and to process the raw materials into biofuels. This report provides information about an opportunity to reuse an abundant water source -- treated municipal wastewater, also known as 'reclaimed water' -- for cooling and process water in electric generating facilities. The report was funded by the U.S. Department of Energy's (DOE's) National Energy Technology Laboratory (NETL) Innovations for Existing Plants research program (Feeley 2005). This program initiated an energy-water research effort in 2003 that includes the availability and use of 'nontraditional sources' of water for use at power plants. This report represents a unique reference for information on the use of reclaimed water for power plant cooling. In particular, the database of reclaimed water user facilities described in Chapter 2 is the first comprehensive national effort to identify and catalog those plants that are using reclaimed water for cooling.

  17. New system of cooling download Arrocampo. Project TEVA; Nuevos sistema refrigeracion descarga Arrocampo. Proyecto TEVA

    Energy Technology Data Exchange (ETDEWEB)

    Puerta Munoz, S.

    2012-07-01

    Project TEVA The new system is basically a mechanical forced-cooling tower, a system of pumping water from Arrocampo, pipes and valves supply a collection basin water tower, a channel to drain the existing auxiliary spillway own shot dam and a new power line from the Central.

  18. WRI 50: Strategies for Cooling Electric Generating Facilities Utilizing Mine Water

    Energy Technology Data Exchange (ETDEWEB)

    Joseph J. Donovan; Brenden Duffy; Bruce R. Leavitt; James Stiles; Tamara Vandivort; Paul Ziemkiewicz

    2004-11-01

    Power generation and water consumption are inextricably linked. Because of this relationship DOE/NETL has funded a competitive research and development initiative to address this relationship. This report is part of that initiative and is in response to DOE/NETL solicitation DE-PS26-03NT41719-0. Thermal electric power generation requires large volumes of water to cool spent steam at the end of the turbine cycle. The required volumes are such that new plant siting is increasingly dependent on the availability of cooling circuit water. Even in the eastern U.S., large rivers such as the Monongahela may no longer be able to support additional, large power stations due to subscription of flow to existing plants, industrial, municipal and navigational requirements. Earlier studies conducted by West Virginia University (WV 132, WV 173 phase I, WV 173 Phase II, WV 173 Phase III, and WV 173 Phase IV in review) have identified that a large potential water resource resides in flooded, abandoned coal mines in the Pittsburgh Coal Basin, and likely elsewhere in the region and nation. This study evaluates the technical and economic potential of the Pittsburgh Coal Basin water source to supply new power plants with cooling water. Two approaches for supplying new power plants were evaluated. Type A employs mine water in conventional, evaporative cooling towers. Type B utilizes earth-coupled cooling with flooded underground mines as the principal heat sink for the power plant reject heat load. Existing mine discharges in the Pittsburgh Coal Basin were evaluated for flow and water quality. Based on this analysis, eight sites were identified where mine water could supply cooling water to a power plant. Three of these sites were employed for pre-engineering design and cost analysis of a Type A water supply system, including mine water collection, treatment, and delivery. This method was also applied to a ''base case'' river-source power plant, for comparison. Mine-water system cost estimates were then compared to the base-case river source estimate. We found that the use of net-alkaline mine water would under current economic conditions be competitive with a river-source in a comparable-size water cooling system. On the other hand, utilization of net acidic water would be higher in operating cost than the river system by 12 percent. This does not account for any environmental benefits that would accrue due to the treatment of acid mine drainage, in many locations an existing public liability. We also found it likely that widespread adoption of mine-water utilization for power plant cooling will require resolution of potential liability and mine-water ownership issues. In summary, Type A mine-water utilization for power plant cooling is considered a strong option for meeting water needs of new plant in selected areas. Analysis of the thermal and water handling requirements for a 600 megawatt power plant indicated that Type B earth coupled cooling would not be feasible for a power plant of this size. It was determined that Type B cooling would be possible, under the right conditions, for power plants of 200 megawatts or less. Based on this finding the feasibility of a 200 megawatt facility was evaluated. A series of mines were identified where a Type B earth-coupled 200 megawatt power plant cooling system might be feasible. Two water handling scenarios were designed to distribute heated power-plant water throughout the mines. Costs were developed for two different pumping scenarios employing a once-through power-plant cooling circuit. Thermal and groundwater flow simulation models were used to simulate the effect of hot water injection into the mine under both pumping strategies and to calculate the return-water temperature over the design life of a plant. Based on these models, staged increases in required mine-water pumping rates are projected to be part of the design, due to gradual heating and loss of heat-sink efficiency of the rock sequence above the mines. Utilizing pumping strategy No.1 (two mines) capital costs wer

  19. Comprehensive cooling water study: Volume 4, Wetlands: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Mackey, H.E. (ed.)

    1987-09-01

    The Comprehensive Cooling Water Study (CCWS) was initiated in 1983 to evaluate the environmental effects of the intake and release of cooling water on the structure and function of aquatic ecosystems at the Savannah River Plant. The initial report (Gladden et al., 1985) described the results from the first year of the study. This document is the final report and concludes the program. The report comprises eight volumes. The first is a summary of environmental effects. The other seven volumes address water quality, radionuclide and heavy metal transport, wetlands, aquatic ecology, Federally endangered species, ecology of Par Pond, and waterfowl. 87 refs. 49 figs., 58 tabs.

  20. Fish culture using cooling water from thermal power plants

    International Nuclear Information System (INIS)

    Special problems associated with the use of heated effluents from thermal power plants in aquaculture include fluctuating temperatures, chemicals added to cooling water, gas supersaturation, and inflexibility in the effluent temperature, in many cases obviating a continuous one year culture cycle. In Sweden, salmonids are the preferred cultural species as long as water temperatures do not exceed 20 deg C during the summer. A pilot fish farm is now using cooling water from he Oskarshamn nuclear power plant. An additional concern in this case will be the accumulation of radioisotopes. (E.C.B.)

  1. Open air-vapor compression refrigeration system for air conditioning and hot water cooled by cool water

    International Nuclear Information System (INIS)

    This paper presents an open air-vapor compression refrigeration system for air conditioning and hot water cooled by cool water and proves its feasibility through performance simulation. Pinch technology is used in analysis of heat exchange in the surface heat exchanger, and the temperature difference at the pinch point is selected as 6 oC. Its refrigeration depends mainly on both air and vapor, more efficient than a conventional air cycle, and the use of turbo-machinery makes this possible. This system could use the cool in the cool water, which could not be used to cool air directly. Also, the heat rejected from this system could be used to heat cool water to 33-40 oC. The sensitivity analysis of COP to ? c and ? t and the simulated results T 4, T 7, T 8, q 1, q 2 and W m of the cycle are given. The simulations show that the COP of this system depends mainly on T 7, ? c and ? t and varies with T 3 or T wet and that this cycle is feasible in some regions, although the COP is sensitive to the efficiencies of the axial compressor and turbine. The optimum pressure ratio in this system could be lower, and this results in a fewer number of stages of the axial compressor. Adjusting the rotation speed of the axial compressor can easily control the pressure ratio, mass flow rate and the refrigerating capacity. The adoption of this cycle will make the air conditioned room more comfortable and reduce the initial investment cost because of the obtained very low temperature air. Humid air is a perfect working fluid for central air conditioning and no cost to the user. The system is more efficient because of using cool water to cool the air before the turbine. In addition, pinch technology is a good method to analyze the wet air heat exchange with water

  2. Prototype solar heating and cooling systems including potable hot water

    Science.gov (United States)

    1978-01-01

    Progress is reviewed in the development, delivery, and support of two prototype solar heating and cooling systems including potable hot water. The system consisted of the following subsystems: collector, auxiliary heating, potable hot water, storage, control, transport, and government-furnished site data acquisition.

  3. Water-cooled units in ultrapower electric arc furnaces

    Science.gov (United States)

    Kuz'min, M. G.; Cherednichenko, V. S.; Bikeev, R. A.; Cherednichenko, M. V.

    2014-12-01

    The thermophysical processes that occur in the skull-metallic pipe-water system under quasistationary and dynamic conditions, when shock heat flows appear, are analyzed. The limiting conditions of water cooling of panels, which are accompanied by the appearance of boiling crisis and pre-emergency and emergency thermophysical processes, are considered.

  4. USE OF PRODUCED WATER IN RECIRCULATING COOLING SYSTEMS AT POWER GENERATING FACILITIES

    Energy Technology Data Exchange (ETDEWEB)

    Michael N. DiFilippo

    2004-08-01

    The purpose of this study is to evaluate produced water as a supplemental source of water for the San Juan Generating Station (SJGS). This study incorporates elements that identify produced water volume and quality, infrastructure to deliver it to SJGS, treatment requirements to use it at the plant, delivery and treatment economics, etc. SJGS, which is operated by Public Service of New Mexico (PNM) is located about 15 miles northwest of Farmington, New Mexico. It has four units with a total generating capacity of about 1,800 MW. The plant uses 22,400 acre-feet of water per year from the San Juan River with most of its demand resulting from cooling tower make-up. The plant is a zero liquid discharge facility and, as such, is well practiced in efficient water use and reuse. For the past few years, New Mexico has been suffering from a severe drought. Climate researchers are predicting the return of very dry weather over the next 30 to 40 years. Concern over the drought has spurred interest in evaluating the use of otherwise unusable saline waters. Deliverable 2 focuses on transportation--the largest obstacle to produced water reuse in the San Juan Basin (the Basin). Most of the produced water in the Basin is stored in tanks at the well head and must be transported by truck to salt water disposal (SWD) facilities prior to injection. Produced water transportation requirements from the well head to SJGS and the availability of existing infrastructure to transport the water are discussed in this deliverable.

  5. Assessment of effectiveness of water mist cooling of casting die

    Directory of Open Access Journals (Sweden)

    R. W?adysiak

    2007-12-01

    Full Text Available At work research findings of the process of cooling the research casting die in the range of the 600-100°C temperature were presented and of the research-production casting die while pouring the cycle out cooled with compressed air about the pressure 0.6 MPa and the water mist about the pressure of air and water appropriately 0.3/0.35 MPa. The character and the speed of the temperature changes in the die and being formed of gradient of the temperature on the thickness partition walls were shown the die with the help of thermal and derivative curves. A course of changes was presented to the density of the thermal stream during cooling and in function of the temperature as well as results were shown a computer simulation of the process of pouring the production casting die. A scheme of the device for generating the water mist cooling the die and an image of spraying water were shown with the help of the designed rotary sprayer. They showed that applying the water mist for cooling dies is increasing the intensity of casting process and is accelerating it.

  6. Cooling water in the study of nuclear power plants sites

    International Nuclear Information System (INIS)

    The location of an electric power plant has its limitations as regards the availability of apt sites. The radiosanitary risk, seismic risk and the overload capacity of the ground can be generically enumerated, being the cooling water availability for an electric power plant a basic requirement. Diverse cooling systems may be employed but the aim must always be that thermal contamination in the immediate environment be the least possible. (Author)

  7. Effect of Oxidizing Bioxides to the Microorganism Growth at RSG-GAS Secondary Cooling Water

    International Nuclear Information System (INIS)

    The RSG-GAS secondary cooling system is open recirculation cooling water. One of the problem at the recirculation open cooling water system is the microorganism growth. To control of the microorganism growth at RSG-GAS secondary cooling system carried out by addition oxidizing biocides chemical and monitoring of the microorganism growth in secondary cooling water. Monitoring of the microorganism growth carried out by determine total count of bacteria in secondary cooling water system with Dipslides Test. From the monitoring result showed that at the secondary cooling system shutdown was the microorganism growth at secondary cooling water system growth faster and than decrease growth after addition of the oxidizing biocides. (author)

  8. Characteristics of cooling water fouling in a heat exchange system

    International Nuclear Information System (INIS)

    This study investigated the efficiency of the physical water treatment method in preventing and controlling fouling accumulation on heat transfer surfaces in a laboratory heat exchange system with tap and artificial water. To investigate the fouling characteristics, an experimental test facility with a plate type heat exchange system was newly built, where cooling and hot water moved in opposite directions forming a counter-flow heat exchanger. The obtained fouling resistances were used to analyze the effects of the physical water treatment on fouling mitigation. Furthermore, the surface tension and pH values of water were also measured. This study compared the fouling characteristics of cooling water in the heat exchange system with and without the mitigation methods for various inlet velocities. In the presence of the electrode devices with a velocity of 0.5m/s, the fouling resistance was reduced by 79% compared to that in the absence of electrode devices

  9. [The behavier of Pseudomonas aeruginosa in surface water, cooling water and waste water (author's transl)].

    Science.gov (United States)

    Botzenhart, K; Wolf, R; Thofern, E

    1975-09-01

    This is a report on the occurrence and numerical behaviour of Ps. aeruginosa in natural waters with and without waste water contamination, in dams, cooling water circulations and cooling water discharge, in clarification plant and supplementary laboratory tests. The results show that Ps. aeruginosa may occur in the natural flora of open waters, but only following the introduction of human sewage. In the main, a more or less rapid reduction in the number of Ps. aeruginosa to low levels occurs, but periods of several days to several weeks must be allowed for this. In the presence of large quantities of nutrient, multiplication of Ps. aeruginosa in natural waters cannot be excluded. It certainly appears in technical systems such as cooling water circuits and filter plants. Presumably Ps. aeruginosa also multiplies in waste water, whereas in the biological aerobic clarification process a reduction occurs. The effect of a higher temperature on the survival or multiplication of Ps. aeruginosa could not be confirmed by laboratory experiments. PMID:811012

  10. Electricity Prices, River Temperatures and Cooling Water Scarcity

    OpenAIRE

    McDermott, Grant; Nilsen, Øivind Anti

    2011-01-01

    Thermal-based power stations rely on water for cooling purposes. These water sources may be subject to incidents of scarcity, environmental regulations and competing economic concerns. This paper analyses the effect of water scarcity and increased river temperatures on German electricity prices from 2002 to 2009. Having controlled for demand effects, the results indicate that the electricity price is significantly impacted by both a change in river temperatures and the relative abundance of r...

  11. Assessment of requirements for dry towers

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, D E; Sonnichsen, J C

    1976-09-01

    The regional limitations of surface water supplies in the U.S. were assessed with respect to the consumptive use requirements of wet cooling towers. The study simulated unit consumptive use factors by region, assessed regional water supplies, and examined electric load projections through 2000 A.D. to ascertain where and when water limitations may occur and, therefore, where dry cooling may be required. It was concluded that the cooling water supply situation in the United States through the year 2000 is adequate in most areas, but is uncertain over much of the Southwest. The uncertainty is related to increasing competition for the available supplies and to potential Federal and/or State policy decisions that may have a significant effect on power plant cooling. Limitations on coastal siting, seismic zone constraints, and state constraints on the purchase and transfer of water rights from other uses to cooling supply have the potential of bringing wet/dry or dry cooling into relatively common use in the 1990's. (LCL)

  12. Cool, elevated chlorophyll-a waters off northern Mozambique

    Science.gov (United States)

    Malauene, B. S.; Shillington, F. A.; Roberts, M. J.; Moloney, C. L.

    2014-02-01

    Direct in-situ observations from a shallow underwater temperature recorder on the continental shelf and from a shipboard oceanographic survey, were combined with MODIS satellite data (sea surface temperature and chlorophyll-a) to assess the temporal and spatial variability of temperature and chlorophyll-a in the Mozambique Channel near the coastal town of Angoche, 16°S. Intermittent, relatively cool surface water and elevated chlorophyll-a signatures were found, indicating upwelling near Angoche over an area between 15°S and 18°S. A 5-year (2002-2007) analysis of temperature (from both in-situ and satellite) revealed two distinct periods: (1) the August-March period with highly variable intermittent "cool water" events and (2) the April-July period with little temperature variability. Generally, periods of cooling occurred at about 2 months intervals, but shorter period occurrences (8-30 days) of cool coastal events were also observed. Two possible forcing mechanisms are discussed: (1) wind derived coastal upwelling (using satellite blended sea surface wind derived from NOAA/NCDC) and (2) the effect of passing transient southward moving eddies (using sea level anomalies from AVISO altimetry). It is suggested that the cool surface, elevated chlorophyll-a waters are primed and formed by favourable wind-driven Ekman-type coastal upwelling, responding to alongshore northeasterly monsoon winds prevailing between August and March. These waters are then enhanced in chlorophyll-a and advected further offshore by anti-cyclonic/cyclonic eddy pairs interacting with the shelf.

  13. Potentials of heat recovery from 850C LEP cooling water

    International Nuclear Information System (INIS)

    Most of the cooling water from LEP has a too low temperature (30 to 400C) to be considered for economical recovery of energy. However, it is hoped that the heat from the klystrons be removed at a temperature of 850C and that this part of the LEP cooling water might be used for saving primary energy. In this study different possibilities have been investigated to make use of the waste heat for heating purposes during winter time, for saving energy in the refrigeration process in summer and for power generation. Cost estimates for these installations are also given and show their economic drawbacks. (orig.)

  14. Assessment of effectiveness of water mist cooling of casting die

    OpenAIRE

    R. W?adysiak

    2007-01-01

    At work research findings of the process of cooling the research casting die in the range of the 600-100°C temperature were presented and of the research-production casting die while pouring the cycle out cooled with compressed air about the pressure 0.6 MPa and the water mist about the pressure of air and water appropriately 0.3/0.35 MPa. The character and the speed of the temperature changes in the die and being formed of gradient of the temperature on the thickness partition walls were sho...

  15. Analytical study of falling water film cooling in PCCS

    International Nuclear Information System (INIS)

    The outer side cooling of containment steel vessel by falling water film in the gap of PCCS is studied through numerical simulation. Simplified boundary layer equations for film are solved with transient turbulent elliptic type equations for air/vapor mixed gases, satisfying interface continuity conditions. The effects of wave that occurs on water film surface were indirectly refleted on eddy viscosity model. The heat transfer at interface of falling water film is larger than that of direct steel vessel cooling by buoyancy-induced air flow, which is dominated by surface evaporation of water film. The developed methodology could by utilized to determine the adeuated PCCS design parameters such as water film mass flow rate, gap size. (Author)

  16. Fundamental study on submerged dischaege of condenser cooling water

    International Nuclear Information System (INIS)

    Most of thermal and nuclear power plants and steel mills in Japan are located in coastal areas to get supply of a large quantity of cooling water from the sea, and the warm waste water from these plants is discharged into the water areas in front of their locations. The effect of the warm waste water on our environment, particularly, on aquatics, has come to draw public attention with the increase of their capacities and concentrated location. In the past, warm waste water was discharged to the surface layer of coastal waters through open channels. Recently, submerged discharging method is given much attention as a new discharging method of warm waste water. This method has a merit that it is capable of larger mixing ratio of the warm waste water and cool sea water around the discharge port. The submerged discharging method is classified into coastal submerged discharge and off-shore submerged discharge. The latter has a merit that it can select mixing ratio of waste water and sea water freely and that it does not have effect on the tidal zone aquatics. In this paper the authors describe the results of their theoretical and experimental studies on the behavior of warm waste water discharged off-shore, pressure loss in discharge pipes and flow rate distribution into discharge port. (auth.)

  17. Computer modeling of lime-soda softening of cooling waters

    International Nuclear Information System (INIS)

    A computer model is developed to fully describe the lime soda ash softening process. This process has a long history of being used to remove calcium and magnesium hardness from cooling waters in order to prevent scaling on heat exchangers. Softening of makeup water and/or a sidestream from the recirculating water will allow a reduction in blowdown. In the extreme case, zero blowdown may be accomplished to conserve cooling waters and to save the costs of disposing of blowdown. Cooling waters differ from most natural waters in having higher temperature and higher concentration of dissolved solids, and, therefore, a higher ionic strength. These factors plus the effects of complex formation are taken into consideration in the development of the computer model. To determine the composition of a softened water, the model assumes that an equilibrium state is reached in a reactor, and employs the equations of mass action and mass balance. The resulting nonlinear simultaneous equations are then linearized by Taylor series expansion and solved by the multidimensional Newton-Raphson method. The computer predictions are compared to the results of laboratory studies using synthetic waters

  18. Conditioning of cooling water in power stations. Feedback from twenty years of experience with acid feeding

    International Nuclear Information System (INIS)

    In the late 1970's and early 1980's, with the development of the nuclear programme in many European countries, the recirculation of cooling water in power stations became an issue which required urgent attention. The concentration of several plants of 1000 MW or more on sites along inland waterways actually made simple once-through cooling impossible, owing to the risk of an unacceptable rise in the river's water temperature. The chemical composition of natural freshwater in western European waterways is such that when it becomes slightly concentrated, scale is rapidly formed. The relatively low solubility of calcium carbonate and the degassing of the carbon dioxide during close contact between the water and air in the heat exchangers of the cooling tower explain this precipitation tendency. Fairly soon, experts in the electricity power generation companies highlighted the need for on-site, pilot loop simulations, in order to foresee the physico-chemical phenomena that could arise in industrial installations. The number of financially justifiable processing possibilities could be briefly summarised by the following three solutions: to adapt the concentration factor in order to be under the calcium carbonate solubility limit and thereby avoid the need for any water conditioning; to accept concentration factors of between 1.4 and 1.9 and control the calcium carbonate precipitation through controlled acid injection in the circulation water; to raise the concentration factor over 5 and soften the makeup water through the addition of lime and flocculant. The last of these solutions was rarely ever used in Belgium and France. It was however widely used in Germany. Its application requires a greater investment and leads to higher operating costs than acid injection. Furthermore, it leads to the problem of daily drying and disposal of several dozen tonnes of sludge, which have to be recycled or dumped. In an increasingly stringent environmental context, this solution is no longer easily justifiable. The research efforts undertaken to better understand and control calcium carbonate precipitation and scale formation have paid off and have resulted in the standardisation of the treatment process and the control procedure of the cooling circuits by ELECTRABEL. The initial experience gained in the fossil power plants of AMERCOEUR (2 x 125 MW units) was finally successfully applied to plants 2 and 3 at TIHANGE. Since then, all of the conventional or combined cycle power plants have adopted the same treatment philosophy. Six units of between 125 and 1000 MW have been treated in this manner, some of them for over twenty years, without showing any signs of scale deposits. It is true that adaptations have had to be made in the control recommendations defined during the pilot trials, in order to allow for the impact of cathodic protections and certain cooling tower fills. (authors)

  19. Cool-Water Carbonates, SEPM Special Publication No. 56

    Science.gov (United States)

    Hallock, Pamela

    Doesn't field work on modern carbonates mean scuba diving on spectacular coral reefs in gin-clear water teeming with brightly colored fish? Not if you are one of the researchers that Jonathan Clarke of the Western Mining Corporation Ltd., in Preston, Victoria, Australia, assembled at a workshop in Geelong, Victoria, in January 1995. Their field work involves research cruises in high-latitude oceans, where mal de mer and chilling winds are constant companions. Many braved 10-m seas in modest-sized research vessels to sample shelves stripped of fine sediments by storm waves whose effects can reach to depths exceeding 200 m. Noel James of Queen's University in Kingston, Ontario, carefully lays the groundwork for the book in a paper titled, “The Cool-Water Carbonate Depositional Realm,” which will assuredly become a standard reading assignment in advanced undergraduate-and graduate-level courses in carbonate sedimentology. James skillfully shows how cool-water carbonates are part of the greater carbonate depositional spectrum. By expanding recognition of the possible range of carbonate environments, sedimentologists expand their ability to understand and interpret ancient carbonates, particularly Paleozoic limestones that often show striking similarities to modern cool-water sediments. James' paper is followed by nine papers on modern cool-water carbonates, seven on Tertiary environments, and seven examples from Mesozoic and Paleozoic limestones

  20. Experimental evaluation of the water ingression mechanism for corium cooling

    International Nuclear Information System (INIS)

    Experiments were performed to assess the significance of water ingression cooling in the quenching of molten corium. Water ingression is a mechanism by which water penetrates into cracks and pores of solidified corium to enhance cooling that would otherwise be severely limited by the low thermal conductivity of the material. Quench tests were conducted with 2100 deg. C melts weighing ?75 kg composed of UO2, ZrO2 and chemical constituents of concrete. The amount of concrete in the melts was varied between 4% and 23%. The melts were quenched with an overlying water layer; three tests were conducted at a system pressure of 1 bar and four tests at 4 bar. The measured cooling rates were found to decrease with increasing concrete content and, contrary to expectations, are essentially independent of system pressure. For the lower concrete content melts, cooling rates exceeded the conduction-limited rate with the difference being attributed to the water ingression mechanism. Measurements of the permeability of the corium 'ingots' produced by the quench tests were used to obtain a second, independent set of dryout heat flux data, which exhibits the same trend as the quench test data. The data was used to validate an existing dryout heat flux model based on corium permeability associated with thermally induced cracking. The model uses the thermal and mechanical properties of the corium and coolant, and it reproduces the very particular data trend found for the dryout heat flux as a function of concrete content. The model predicts that water ingression cooling would be most effective for concrete-free corium mixtures such as in-vessel type melts. For such a melt the model predicts a dryout heat flux of ?400 kW/m2 at a pressure of 1 bar. The results of this study provide an experimental basis for a water ingression model that can be incorporated into computer codes used to assess accident management strategies

  1. Test apparatus for ITER blanket cooling water distributor design

    International Nuclear Information System (INIS)

    Current Japanese breeding blanket concept being developed for the ITER driver blanket is comprised of three breeding layers, nine multiplier layers and five water cooling panels. In order to meet design requirements of tritium release efficiency and material temperature restrictions, configuration of these layers should be designed to achieve optimum temperature profiles in the radial direction of the blanket. Such temperature conditions are attained by appropriate water flow rate distribution in each cooling panel. Furthermore, the cooling panel must be designed to accommodate variation of D-T burning plasma density during ITER operation. We have developed an engineering test apparatus composed of three parallel cooling panel models. It was designed to examine performance of orifice type passive distributions for cooling header design. The apparatus can be operated under ITER blanket design conditions: temperature range; 60 - 100degC, water pressure; 1.5MPa, flow rate; 0.5-5m/s, pressure drop; up to 50kPa, heat flux of heater; 20-2000kW/m2. (author)

  2. POOL WATER TREATMENT AND COOLING SYSTEM DESCRIPTION DOCUMENT

    International Nuclear Information System (INIS)

    The Pool Water Treatment and Cooling System is located in the Waste Handling Building (WHB), and is comprised of various process subsystems designed to support waste handling operations. This system maintains the pool water temperature within an acceptable range, maintains water quality standards that support remote underwater operations and prevent corrosion, detects leakage from the pool liner, provides the capability to remove debris from the pool, controls the pool water level, and helps limit radiological exposure to personnel. The pool structure and liner, pool lighting, and the fuel staging racks in the pool are not within the scope of the Pool Water Treatment and Cooling System. Pool water temperature control is accomplished by circulating the pool water through heat exchangers. Adequate circulation and mixing of the pool water is provided to prevent localized thermal hotspots in the pool. Treatment of the pool water is accomplished by a water treatment system that circulates the pool water through filters, and ion exchange units. These water treatment units remove radioactive and non-radioactive particulate and dissolved solids from the water, thereby providing the water clarity needed to conduct waste handling operations. The system also controls pool water chemistry to prevent advanced corrosion of the pool liner, pool components, and fuel assemblies. Removal of radioactivity from the pool water contributes to the project ALARA (as low as is reasonably achievable) goals. A leak detection system is provided to detect and alarm leaks through the pool liner. The pool level control system monitors the water level to ensure that the minimum water level required for adequate radiological shielding is maintained. Through interface with a demineralized water system, adequate makeup is provided to compensate for loss of water inventory through evaporation and waste handling operations. Interface with the Site Radiological Monitoring System provides continuous radiological monitoring of the pool water. The Pool Water Treatment and Cooling System interfaces with the Waste Handling Building System, Site-Generated Radiological Waste Handling System, Site Radiological Monitoring System, Waste Handling Building Electrical System, Site Water System, and the Monitored Geologic Repository Operations Monitoring and Control System

  3. Hydrogen treating device in water cooled reactor

    International Nuclear Information System (INIS)

    Purpose: To absorb and recover hydrogen gases produced in a nuclear power plant for reuse. Constitution: A processing device incorporating hydrogen storage alloy is disposed at the root of waste disposing system or reactor water system. Since hydrogen in the form of hydrides is used instead of highly explosive gaseous form, it can be stored with no risk of explosion. This can eliminate the hydrogen concentration reducing treatment by the addition of the steam or N2 gas sealing conducted so far for the prevention of the explosion. Further, the entire value of the exhaust gas is also decreased. In addition, by controlling the temperature of the hydrogen storage alloy, hydrogen can be released from the alloy and supplied to the reactor water. TiFe, Mg2Ni, LaNi5 or like other hydrogen storage alloys are known. (Ikeda, J.)

  4. Introduction of variable operational conditions for water cooled reactors

    International Nuclear Information System (INIS)

    State of the problem of water cooled reactor transition to operational condition with variable load is described. Peculiarities of control systems for fast change of power applied in France, USA and FRG are discussed. The importance of in-core monitoring to provide reactor operation safety at full load cycles is shown. Fuel reliability, when reactor operates under variable conditions, is analyzed

  5. 244-AR vault cooling water stream-specific report

    International Nuclear Information System (INIS)

    The proposed wastestream designation for the 244-AR Vault cooling water wastestream is that this stream is not a dangerous waste, pursuant to the Washington (State) Administration Code (WAC) 173-303, Dangerous Waste Regulations. A combination of process knowledge and sampling data was used to make this determination. 21 refs., 6 figs., 7 tabs

  6. Computational Simulation of a Water-Cooled Heat Pump

    Science.gov (United States)

    Bozarth, Duane

    2008-01-01

    A Fortran-language computer program for simulating the operation of a water-cooled vapor-compression heat pump in any orientation with respect to gravity has been developed by modifying a prior general-purpose heat-pump design code used at Oak Ridge National Laboratory (ORNL).

  7. Methodologies for estimating air emissions from three non-traditional source categories: Oil spills, petroleum vessel loading and unloading, and cooling towers. Final report, October 1991-March 1993

    International Nuclear Information System (INIS)

    The report discusses part of EPA's program to identify and characterize emissions sources not currently accounted for by either the existing Aerometric Information Retrieval System (AIRS) or State Implementation Plan (SIP) area source methodologies and to develop appropriate emissions estimation methodologies and emission factors for a group of these source categories. Based on the results of the identification and characterization portions of this research, three source categories were selected for methodology and emission factor development: oil spills, petroleum vessel loading and unloading, and cooling towers. The report describes the category selection process and presents emissions estimation methodologies and emission factor data for the selected source categories. The discussions for each category include general background information, emissions generation activities, pollutants emitted, sources of activity and pollutant data, emissions estimation methodologies and data issues. The information used in these discussions was derived from various sources including available literature, industrial and trade association publications and contracts, experts on the category and activity, and knowledgeable federal and state personnel

  8. Grohnde. Documentation of the police operation during the demonstration against the NPP Grohnde on 19.03.1977 and the evacuation of the occupied cooling tower site on 23.08.1977

    International Nuclear Information System (INIS)

    The documentation of the police operation during the demonstration against the NPP Grohnde on 16.03.1977 and the evacuation of the occupied cooling tower site on 23.08.1977 covers the following issues: involved action forces: police Niedersachsen, police Nordrhein-Westfalen, police Schleswig-Holstein, police Bremen and the Bundesgrenzschutz; concept of the police operation, provisions (lodging and board) for the police, operating resources, details of the operation sequence; post-processing of the operation; the Grohnde trials.

  9. Natural Circulation Phenomena and Modelling for Advanced Water Cooled Reactors

    International Nuclear Information System (INIS)

    The role of natural circulation in advanced water cooled reactor design has been extended with the adoption of passive safety systems. Some designs utilize natural circulation to remove core heat during normal operation. Most passive safety systems used in evolutionary and innovative water cooled reactor designs are driven by natural circulation. The use of passive systems based on natural circulation can eliminate the costs associated with the installation, maintenance and operation of active systems that require multiple pumps with independent and redundant electric power supplies. However, considering the weak driving forces of passive systems based on natural circulation, careful design and analysis methods must be employed to ensure that the systems perform their intended functions. Several IAEA Member States with advanced reactor development programmes are actively conducting investigations of natural circulation to support the development of advanced water cooled reactor designs with passive safety systems. To foster international collaboration on the enabling technology of passive systems that utilize natural circulation, in 2004 the IAEA initiated a coordinated research project (CRP) on Natural Circulation Phenomena, Modelling and Reliability of Passive Systems that Utilize Natural Circulation. Three reports were published within the framework of this CRP. The first report (IAEA-TECDOC-1474) contains the material developed for the first IAEA training course on natural circulation in water cooled nuclear power plants. The second report (IAEA-TECDOC-1624) describes passive safety systems in a wide range of advanced water cooled nuclear power plant designs, with the goal of gaining insights into system design, operation and reliability. This third, and last, report summarizes the research studies completed by participating institutes during the CRP period.

  10. Effect of Power Plant Cooling Water Discharge upon Water Quality in the Tokyo Bay

    Science.gov (United States)

    Kitahara, Kouichi; Wada, Akira; Uehara, Yoshikazu; Fukuoka, Ippei; Kawanaga, Mitsuhito; Takano, Tairyu

    Water quality in the Tokyo Bay is controlled by the load input from rivers, seawater currents, temperature variation, photosynthetic processes and others. On the other hand, 23.5 GJ/s of heat, as of 1995, is discharged into the Bay as cooling water effluent from thermal power plants along the coast. Low temperature water of bottom layers is pumped up and utilized as cooling water in thermal power plants. Although the intake and discharge of cooling water may influence water quality of coastal and inner bay areas where power plants are sited, few quantitative evaluations of the effects of cooling water on the water quality have been made yet. In the present study, we report a result of computations to predict the effects of cooling water discharge on the water quality of the Tokyo Bay in the summer, based on a "primary ecological model" for two thermal conditions: the current heat discharge of 23.5 GJ/s, and a heat discharge of 28.9 GJ/s which is expected in the future. Flow and water temperature distribution data, computed by Kitahara et al.(2003), were used to run the model. It was concluded that except in the vicinities of outlet points, water quality of the Tokyo Bay in the summer might be little changed by the future increase of 5.4 GJ/s of heat discharge.

  11. Can rupture detector for water cooled piles

    International Nuclear Information System (INIS)

    The object of this study was to develop a simple, easy to-build, apparatus for showing the appearance of a defect on a fuel element can of a swimming pool reactor. The apparatus used consists of a coil of activated carbon around a NaI(Tl) crystal. Through this coil pass the gases obtained by degassing a sample of water from the reactor; the fission gases which appear when a can leaks are trapped in the carbon; the NaI(Tl) crystal is coupled with a photomultiplier followed by a single-channel selector fixed on a photo-electric peak characteristic of the ? spectrum of fission gases. Preliminary experiments were carried out in laboratory; a more complete device was then built and is now working in the reactor Melusine. (author)

  12. Procedure for operating a heavy water cooled power reactor

    International Nuclear Information System (INIS)

    Nuclear reactors cooled by heavy water usually have equipment for fuel element exchange during operation, with the primary circuit remaining contained. This fuel element exchange equipment is expensive and complicated in many respects. According to the invention, the heavy water is therefore replaced by light water after a certain time of operation in such way that light water is led in and heavy water is led off. After the replacement, at least a quarter of the fuel elements of the reactor core is exchanged with the reactor pressure vessel being open. Then the light water serving as a shielding is replaced by heavy water, with the reactor pressure vessel being closed. The invention is of interest particularly for high-conversion reactors. (orig.)

  13. Distributed power from solar tower systems : a MIUS approach

    Energy Technology Data Exchange (ETDEWEB)

    Romero, M.; Marcos, M.J.; Tellez, F.M.; Blanco, M. [CIEMAT/DER-PSA, Madrid (Spain); Fernandez, V. [AICIA, Escuela Superior de Ingenieros, Seville (Spain); Baonza, F. [Escuela Politecnica Superior, Madrid (Spain). Dpto. Ingenieria Mecanica; Berger, S. [Ecole Nat. des Ponts et Chaussees, Marne-la-Vallee (France)

    1999-07-01

    One of the short-term priorities for renewable energies in Europe is their integration into communities and energy islands for local power supply (blocks of buildings, new neighborhoods in residential areas, shopping centers, hospitals, recreational areas, ecoparks, small rural areas or isolated ones such as islands or mountain communities). Following this strategy, the integration of small solar tower fields into so-called MIUS (Modular Integrated Utility Systems) is proposed. This application strongly influences field concepts leading to modular multi-tower systems able to more closely track demand, meet reliability requirements with fewer megawatts of installed power and spread construction costs over time after output has begun. In addition, integration into single-cycle high-efficiency gas turbines plus waste-heat applications clearly increments the solar share. The main questions are whether solar towers can be redesigned for such distributed markets and how to make them feasible. This paper includes the design and performance analysis of a 1.36 MW plant and its integration in the MIUS system, as well as the expected cost of electricity and a sensitivity analysis of the small tower plant's performance with design parameters like heliostat configuration and tower height. A practical application is analyzed for a shopping center with a solar tower producing electricity and waste heat for hot water and heating and cooling of spaces. (Author)

  14. Isolation and identification of legionellosis agents from fishponds, swimming pools and cooling towers in Khuzestan province, Iran

    Directory of Open Access Journals (Sweden)

    Amir Dashti

    2011-10-01

    Full Text Available Introduction and objective: Legionella are the causative agents of pneumonia in human and it is reported that up to 90% cases of legionnaires` disease are due to Legionella pneumophila. These organisms are ubiquitous distributed in natural and man made water sources. They are spread to human by inhalation or aspiration of contaminated aerosols of these sources. We studied some of man made water sources in view of the presence of Legionella, by two methods of culture and PCR. Materials and methods: One hundred and fifty water samples collected from different man made water sources were examined. After acidic treatment of samples, water pellet was inoculated onto buffered charcoal yeast extract agar (BCYE and BMPA (BCYE supplemented with three antibiotics media. Isolated colonies were identified by morphological and biochemical tests. DNA was extracted from the bacteria and was used for PCR technique. DNA pattern of Legionella were identified after electrophoresis of PCR products.Results: Survey of water samples collected from different sources resulted in isolation of Legionella pneumophila (7.3% by culture, and identification of them (15.3% by PCR. The highest isolates of L. pneumophila were from fish ponds in rates of 6.6% by culture and 13.3% by PCR method. Sensitivity and specificity of PCR in this survey were 100% and 95%, respectively. Conclusion: This study showed that legionnaires` disease agents were widely spread in our examined water sources and compared with culture; PCR method has suitable sensitivity and specificity for rapid detection of these organisms in environmental water sources. Significance and impact of the study: The results of this study will increase physicians and microbiologists awareness about spreading of Legionella and this will be useful for control of legionellosis agents.

  15. Cooling rate, heating rate and aging effects in glassy water

    CERN Document Server

    Giovambattista, N; Sciortino, F; Giovambattista, Nicolas; Sciortino, Francesco

    2004-01-01

    We report a molecular dynamics simulation study of the properties of the potential energy landscape sampled by a system of water molecules during the process of generating a glass by cooling, and during the process of regenerating the equilibrium liquid by heating the glass. We study the dependence of these processes on the cooling/heating rates as well as on the role of aging (the time elapsed in the glass state). We compare the properties of the potential energy landscape sampled during these processes with the corresponding properties sampled in the liquid equilibrium state to elucidate under which conditions glass configurations can be associated with equilibrium liquid configurations.

  16. Corrosion of hollow conductors of water cooled generator stator windings

    International Nuclear Information System (INIS)

    After the observation of the plugging phenomenon, due to copper oxidation, in stator conductors of French PWR units, theoretical studies pointed out the importance of the gaseous conditioning of cooling water; research tests have been carried out on corrosion loops. The results of these works allow to understand the complex mechanism of copper oxidation in a neutral aqueous medium. The experience and the results of these experiments led EDF and Alsthom to condition with air the surge tanks of stator winding cooling systems of the CP1 series, those of Fessenheim and Bugey alternators being so conditioned since the beginning

  17. Technology for Water Treatment

    Science.gov (United States)

    1992-01-01

    There are approximately 500,000 water cooling towers in the United States, all of which must be kept clear of "scale" and corrosion and free of pollutants and bacteria. Electron Pure, Ltd. manufactures a hydro cooling tower conditioner as well as an automatic pool sanitizer. The pool sanitizer consists of two copper/silver electrodes placed in a chamber mounted in the pool's recirculation system. The tower conditioner combines the ionization system with a water conditioner, pump, centrifugal solids separator and timer. The system saves water, eliminates algae and operates maintenance and chemical free. The company has over 100 distributors in the U.S. as well as others in 20 foreign countries. The buildup of scale and corrosion is the most costly maintenance problem in cooling tower operation. Jet Propulsion Laboratory successfully developed a non-chemical system that not only curbed scale and corrosion, but also offered advantages in water conservation, cost savings and the elimination of toxic chemical discharge. In the system, ozone is produced by an on-site generator and introduced to the cooling tower water. Organic impurities are oxidized, and the dissolved ozone removes bacteria and scale. National Water Management, a NASA licensee, has installed its ozone advantage systems at some 200 cooling towers. Customers have saved money and eliminated chemical storage and discharge.

  18. Hydrogen production using water cooled reactors

    International Nuclear Information System (INIS)

    Full text: Today the world is facing tremendous energy challenges. There is a demographic explosion, which even in the most conservative scenario will drive the energy demand to high levels whilst at the same time fossil resources are becoming scarcer, and more particularly oil which bears most of the weight in the transportation area. Global warming is also becoming a major concern as the last Intergovernmental Panel on Climate Change concluded that anthropogenic greenhouse gases (GHG) are responsible for most of the observed temperature increase since the middle of the twentieth century. To address these difficulties, the first step is to look for ways to save energy whenever possible. Then, the part of GHG free sources - renewable energies (wind, solar, hydraulic, biomass) as well as nuclear energy - has to be increased in electricity production. Lastly, since the part of electricity in the final consumption of energy is less than 20% worldwide, GHG free sources of energy have to look for other markets such as transportation, whether directly (electric cars) or indirectly via hydrogen (fuel cells) and/or process heat. Hydrogen is produced currently from fossil fuels (less than 5% is produced by splitting water), and production is increasing steadily, mostly because of its use for refining crude oil and the more demanding standards of purity required. This alone is already stimulating interest in producing hydrogen by sustainable means. Moreover, the hydrogen market is bound to expand soon: hydrogen has been identified as a leading candidate for transport applications. A near term solution is to use the hydrogen produced together with a carbon source (biomass, coal, waste, CO2) to make synthetic fuel. A longer term and more hypothetical development could be the direct use of hydrogen to power cars. Hydrogen could also be used in the iron and cement industries as a reducing agent and also help these CO2 intensive industries to significantly decrease their GHG emissions. The French context has also to be taken into account. More than 80% of electricity is produced by nuclear power plants and the hour to hour variations of the electricity demand have to be absorbed by having some plants operating at intermediate power over significant periods of time. This situation presents the double drawback of not taking full benefit of an expensive investment as well as having to take careful steps when going back to full power in order to preserve the fuel cladding. Hydrogen production during off peak periods could help regulate the electricity demand and operate the nuclear plants in base load. This then requires hydrogen production means that are flexible and not investment intensive, as they would be used only on a part time basis. CEA's strategy is hence to focus on processes which could be coupled to nuclear plants or renewable energy sources and thus be able to produce hydrogen in a sustainable way, by splitting the water molecule using GHG free electricity and/or heat. Low temperature electrolysis, even if it is used currently for limited amounts, is a mature technology which uses only electricity and can be generalized in the near future. However, this technology, which requires about 4 kWh of electricity per Nm of hydrogen produced, is energy intensive and therefore three advanced processes have also been investigated: High temperature steam electrolysis (HTSE), the Sulfur-Iodine (S-I) and Hybrid sulfur (HyS) thermochemical cycles. These processes look promising but the last two require the development of high temperature reactors, still necessitate extensive R and D work and will not be mature for industrial development within the next 20 years. Therefore, beside the optimization of LTE, our focus will be on HTSE, which will be available sooner and can also operate in autothermal mode, offering the capacity to be coupled to a LWR. In this paper, we will present the French road map for hydrogen production. (author)

  19. Engineered safeguard systems for the prototype heavy water moderated, boiling light water cooled reactor 'FUGEN'

    International Nuclear Information System (INIS)

    The prototype heavy water-moderated, boiling light water-cooled reactor, or Advanced Thermal Reactor, ''FUGEN'' is different in many respects from conventional light water reactors because of its construction comprising multipressure-tube core. This report describes on the emergency core cooling system of FUGEN and the results of examining the adaptability to the new evaluation guide proposed for that of light water reactors. The emergency core cooling system of FUGEN is composed of 3 injection systems, each comprising two independent systems. The analysis code S are used to evaluate cooling water behaviour and the operation of emergency core cooling system, and have been improved or the unsettled parameters were determined, and the reliability was confirmed by the results of experiments. The basic concept of the ''new evaluation guide for emergency core cooling system of light water reactors'' is (1) requirement of exact backing data, (2) consideration of appropriate safety allowance for backing data, and (3) adoption and proof of more detailed physical model. The discussed results show that the max. temperature of cald tubes is 9900C even taking fuel deformation in consideration, and sufficiently lower than 12000C, the reference value indicated in the guide. Thus the core safety of FUGEN has been confirmed to be fully maintained with the present emergency core cooling system. (Wakatsuki, Y.)

  20. Materials challenges for the Supercritical Water-Cooled Reactor (SCWR)

    International Nuclear Information System (INIS)

    This paper discusses the materials requirements of the Supercritical Water-cooled Reactor (SCWR) which arise from its severe expected operating conditions: (i) Outlet Temperature (to 650 C); (ii) Pressure of 25 MPa for the coolant containment, (iii) Thermochemical stress in the presence of supercritical water, and (iv) Radiative damage (up to 150 dpa for the fast spectrum variant). These operating conditions are reviewed; the phenomenology of materials in the supercritical water environment that create the materials challenges is discussed; knowledge gaps are identified, and efforts to understand material behaviour under the operating conditions expected in the SCWR are described. (author)