WorldWideScience

Sample records for cooling tower water

  1. 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.

  2. 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

  3. Light water nuclear power station with dry cooling tower

    International Nuclear Information System (INIS)

    A sufficient cooling system is to be guaranteed for light water nuclear power stations, which are installed in areas with little water and for which dry cooling towers are provided. It is therefore proposed to divide the cooling water into equal parts. Each partial condenser, which is associated with an exhaust steam flow from the LP turbine has its own closed coolant circuit. It includes the cooling water pipes, cooling water pumps and one dry cooling tower each. (UWI)

  4. Cooling tower water circuits with raceways

    International Nuclear Information System (INIS)

    Two physical models built at the National Hydraulics Laboratory in Chatou have led to the determination of the design of the works. This new design economizes 4 to 5 MW on pumping power for each cooling tower

  5. 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

  6. 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.

  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. Cooling towers

    International Nuclear Information System (INIS)

    The need for the use of cooling systems in power plant engineering is dealt with from the point of view of a non-polluting form of energy production. The various cooling system concepts up to the modern natural-draught cooling towers are illustrated by examples. (TK/AK)

  9. 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.

  10. 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

  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. 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.

  13. 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.)

  14. 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

  15. 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

  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. 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

  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. 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.

  20. In Hot Water: A Cooling Tower Case Study. Instructor's Manual

    Science.gov (United States)

    Cochran, Justin; Raju, P. K.; Sankar, Chetan

    2005-01-01

    Vogtle Electric Generating Plant operated by Southern Nuclear Operating Company, a subsidiary of Southern Company, has found itself at a decision point. Vogtle depends on their natural draft cooling towers to remove heat from the power cycle. Depending on the efficiency of the towers, the cycle can realize more or less power output. The efficiency…

  1. Complex development of cooling towers

    International Nuclear Information System (INIS)

    Development of the design of cooling towers and recirculated cooling water systems at the Industrial Design Co. (IPARTERV). Cooling technological elements, drift eliminators, water distribution systems, water spray equipments, packings. Building technology, building constructions. Reconstruction of cooling towers. Desirable future of the power economy

  2. 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

  3. 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

  4. 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.

  5. 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...

  6. 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.)

  7. 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.

  8. 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

  9. 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.

  10. 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)

  11. Effects of cooling towers

    International Nuclear Information System (INIS)

    A description 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. (DG)

  12. 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.

  13. Cooling towers. A bibliography

    International Nuclear Information System (INIS)

    Included are 905 citations to references on cooling towers for fossil-fuel or nuclear power plants. A few citations are included on other types of condenser cooling systems, e.g., cooling ponds and canals. Corporate Author, Personal Author, Report Number/Availability, and Subject Indexes are provided

  14. 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...

  15. 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.

  16. High performance cooling towers

    International Nuclear Information System (INIS)

    To carry out the extension, in size and number, of its cooling towers, E.D.F. has been undertaking for the last ten years an extensive research and development program on this equipment. Studies have especially dealt with the aerodynamic and thermal behaviour of the towers. On site and test facility studies, numerical and experimental simulations, jointly performed, have contributed to a considerable improvement of components and design and to the development of reliable forecasting tools

  17. Cooling towers: a bibliography

    International Nuclear Information System (INIS)

    Included are 214 citations to references on cooling towers for fossil-fuel or nuclear power plants. A few citations are included on other types of condenser cooling systems, e.g., cooling ponds and canals. The citations were taken from the ERDA Energy Information Data Base (EDB) covering the approximate period June 1977 to December 1977. Corporate, Personal Author, Subject, and Report Number indexes are provided

  18. 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

  19. Hydraulic works study of Golfech cooling towers

    International Nuclear Information System (INIS)

    The GOLFECH Nuclear Power Plant cooling towers (PWR 2 x 1300 MWe), built by SCAM for EDF (French National Electricity Authority), have certain characteristics, including: tower height - 178.50 metres; shell support - made up of a profiled lintel resting on piles; cooled water recovery system installed immediately below the fill; and cold water basin built outside the cooling tower. This paper deals only with the hydraulic circuit design (warm water inlet, cooled water recovery, cooled water return) with particular emphasis on the limitations of conventional methods of hydraulic sizing and, the necessity to carry out tests using models in order to dimension such works

  20. 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.

  1. Experimental investigations on the contribution of the splash-zones in counter-flow cooling towers for water cooling

    International Nuclear Information System (INIS)

    The relatively high cost of cooling tower packs has led to investigate the contribution of the splash-zones in counter-flow cooling towers, and thereby to determine whether the pack could not be reduced so far, as to be - under certain circumstance - completely eliminated. In this case, one would come to a pure splash cooling tower which would contain inside the equipment required for drop formation only. This problem was investigated experimentally, and it was found that the pack of such a cooling tower could not be eliminated without a reduction in tower effectiveness. (orig.)

  2. Cooling towers for nuclear power

    International Nuclear Information System (INIS)

    Briefly described is the design of cooling towers of the Dukovany, Mochovce and Temelin nuclear power plants. The Dukovany cooling tower is designed as an intermediate type of cooling tower for nuclear power plants with WWER-440 reactors. For the Mochovce power plant the type has been innovated by the use of plastics. The design of the Temelin cooling tower incorporates all progressive elements previously used for nuclear power plants with WWER-440 reactors. The concept of only one cooling tower for every 1000 MW unit will be introduced after 1990. (J.B.). 2 figs

  3. Recent developments in cooling towers

    International Nuclear Information System (INIS)

    The last few years have brought about some interesting developments in large cooling towers. Cooling tower technology and research have already been reviewed from the researcher's point of view. The present article describes some practical problems from the planning engineer's point of view. Only development trends in wet natural-draught cooling towers are considered. The shape of cooling towers has been improved as well as their internals. Hints for cooling tower operation are given on the basis of operating experience in winter. (orig.)

  4. New painting on Mochovce cooling towers

    International Nuclear Information System (INIS)

    New protective painting on the south cooling towers is included in the maintenance and modernization project. Slovenske elektrarne have modernized not only concrete surface of the civil structure, but also internal technology of the cooling tower and its cooing efficiency is increased without increasing consumption of the cooling water. The project will continue this and following year on towers of the units No. 1 and 2 at the Mochovce Nuclear Power Plant. Similar works have been already performed on the cooling towers on units 3 and 4 at the Bohunice Nuclear Power Plant and Mochovce Nuclear Power Plant units 3 and 4. (author)

  5. 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

  6. 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.

  7. 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)

  8. Ozone Treatment For Cooling Towers

    Science.gov (United States)

    Blackwelder, Rick; Baldwin, Leroy V.; Feeney, Ellen S.

    1990-01-01

    Report presents results of study of cooling tower in which water treated with ozone instead of usual chemical agents. Bacteria and scale reduced without pollution and at low cost. Operating and maintenance costs with treatment about 30 percent of those of treatment by other chemicals. Corrosion rates no greater than with other chemicals. Advantage of ozone, even though poisonous, quickly detected by smell in very low concentrations.

  9. 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

  10. Environmental impact assessment of cooling towers

    International Nuclear Information System (INIS)

    Downstream and downwind environmental impact of cooling water towers is reported and evaluated. Salt and chemical concentrations affecting downstream ecology in the atmosphere and in fresh and salt water are calculated, and specific examples of large-scale effects are given. Drift losses from towers and the extent and severity of the concurrent effect of chemicals are discussed, including the effects of chromium and zinc. Tower configuration, control measures, and climatic factors influencing mist distribution are explored and reported

  11. 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

  12. Induced draught circular cooling tower

    International Nuclear Information System (INIS)

    Induced draught atmospheric cooling towers are described, to wit those in which the circulation is by power fans. This technique with fans grouped together in the centre enables a single tower to be used and provides an excellent integration of the steam wreath into the atmosphere. This type of cooling tower has been chosen for fitting out two 900 MW units of the Chinon power station in France

  13. 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)

  14. Cooling towers principles and practice

    CERN Document Server

    Hill, G B; Osborn, Peter D

    2013-01-01

    Cooling Towers: Principles and Practice, Third Edition, aims to provide the reader with a better understanding of the theory and practice, so that installations are correctly designed and operated. As with all branches of engineering, new technology calls for a level of technical knowledge which becomes progressively higher; this new edition seeks to ensure that the principles and practice of cooling towers are set against a background of up-to-date technology. The book is organized into three sections. Section A on cooling tower practice covers topics such as the design and operation of c

  15. 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.

  16. 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.)

  17. 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)

  18. Statistics Analysis Measures Painting of Cooling Tower

    OpenAIRE

    Zacharopoulou, A.; Zacharopoulou, E.; G. Batis

    2013-01-01

    This study refers to the cooling tower of Megalopolis (construction 1975) and protection from corrosive environment. The maintenance of the cooling tower took place in 2008. The cooling tower was badly damaged from corrosion of reinforcement. The parabolic cooling towers (factory of electrical power) are a typical example of construction, which has a special aggressive environment. The protection of cooling towers is usually achieved through organic coatings. Because of the different environm...

  19. Legionella species and serogroups in Malaysian water cooling towers: identification by latex agglutination and PCR-DNA sequencing of isolates.

    Science.gov (United States)

    Yong, Stacey Foong Yee; Goh, Fen-Ning; Ngeow, Yun Fong

    2010-03-01

    In this study, we investigated the distribution of Legionella species in water cooling towers located in different parts of Malaysia to obtain information that may inform public health policies for the prevention of legionellosis. A total of 20 water samples were collected from 11 cooling towers located in three different states in east, west and south Malaysia. The samples were concentrated by filtration and treated with an acid buffer before plating on to BCYE agar. Legionella viable counts in these samples ranged from 100 to 2,000 CFU ml(-1); 28 isolates from the 24 samples were examined by latex agglutination as well as 16S rRNA and rpoB PCR-DNA sequencing. These isolates were identified as Legionella pneumophila serogroup 1 (35.7%), L. pneumophila serogroup 2-14 (39%), L. pneumophila non-groupable (10.7%), L. busanensis, L. gormanii, L. anisa and L. gresilensis. L. pneumophila was clearly the predominant species at all sampling sites. Repeat sampling from the same cooling tower and testing different colonies from the same water sample showed concurrent colonization by different serogroups and different species of Legionella in some of the cooling towers. PMID:20009251

  20. Survey of asbestos fibers in cooling tower waters at Goodyear Atomic Corporation

    International Nuclear Information System (INIS)

    Monitoring of the recirculating water (RCW) system at Goodyear Atomic Corporation has been performed since late 1975, when detectable amounts of asbestos were found in the RCW. From August 1976 through may 1979, fiber counts varied from below detectable limits (0.7 x 106 fibers/liter) to 16.2 x 106 fibers/liter in the cooling tower water. These results were nearly identical to the initial asbestos fiber data obtained for RCW from December 1975 through July 1976. From January 1977 through May 1979, water samples from the X-616 Chromate Recovery Facility effluent and the X-611 Water Treatment Plant (RCW makeup) were also analyzed for asbestos, and fiber counts varied from below detectable limits to 0.7 x 106 fibers; liter and 1.4 x 106 fibers/liter, respectively. The number of fibers in the RCW system and at the X-611 and X-616 facilities does not present an environmental problem at this time. Beginning in June 1978, all samples collected were prepared for analysis by two methods after a United States Environmental Protection Agency-sponsored study demonstrated that a method different from the one used at Goodyear Atomic Corporation had essentially zero fiber losses. To date, no significant differences have been observed between the two methods. In the future, monitoring of asbestos fibers should continue on a periodic basis to determine if an asbestos fiber problem develops.Both methods of sample preparation should be utilized to firmly establish which method is best

  1. 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.

  2. On some problems of operation of circulating systems with cooling tower under high hardness and mineralization of make-up water

    International Nuclear Information System (INIS)

    This presentation addresses the deposit of calcium carbonate on the packings of cooling towers. The resistance of several materials to scaling is investigated as well as the effect of the scaling on the performance of the cooling tower. Water treatment to reduce scaling is also addressed

  3. 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

  4. 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.

  5. 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...

  6. Discussion on Energy-saving Applications of Fanless Cooling Tower

    Directory of Open Access Journals (Sweden)

    Kuang-Cheng Yu

    2011-01-01

    Full Text Available Cooling tower is essential to both industrial development and comfortable living. Its development is closely related to human civilization and quality of life. To achieve the cooling effects and the efficiency performance of high inlet/outlet water temperature difference (?t of cooling towers, a number of modern high technologies have been applied, while the design of cooling towers focuses on lightweight, compact size, elegant appearance, and durability. This study studied the performance of fanless cooling tower when applied in a chiller cooling water system of the central air-conditioning in a hospital and discussed the problems and solutions that the fanless cooling tower encountered during practical use and explored whether there is any room to improve energy conservation according to the data recorded in the process of operation. This study also verified the performance and advantages as specified by the manufacturer to provide a reference to the design and installation of same type cooling towers in the future.

  7. Dynamic analysis of cooling towers

    International Nuclear Information System (INIS)

    Natural draught cooling towers are shell structures subjected to random vibrations due to wind turbulence and earthquake. The need of big power plant units has initiated the design of very large cooling towers. The random response of such structures may be analysed using a spectral approach and assuming a linear behaviour of the structure. As the modal superposition method is the most suitable procedure for this purpose it is necessary to determine the natural frequencies and mode shapes with adequate accuracy. (orig./GL)

  8. The effect of civil engineering and access conditions on the cooling water pumps and the various types of cooling water pumps for cooling towers

    International Nuclear Information System (INIS)

    Starting with the pump inlet construction one can see that the designer must decide early on between the acceleration bend and the inlet chamber. To achieve smooth flow, four main conditions must be largely fulfilled. The rotor of cooling tower pumps is usually of the semiaxial type, where one must distinguish between non-adjustable, settable and adjustable rotors. The cooling tower pumps for drain and recirculation cooling are preferably made as spiral casing pumps. For nominal sizes of 1600 and larger, the pump casings are made of concrete, for economic reasons. For combined cooling, the type of pipe casing is decided for the same reasons. The above nominal size limit again decides a conrete design. Of the well-known control processes, the pre-rotor and rotor blade adjustment are at present the most economical. Both types of control are compared. (orig.)

  9. FIELD INVESTIGATION OF COOLING TOWER AND COOLING POND PLUMES

    Science.gov (United States)

    Measurements were made relating to the behavior of water-vapor plumes from forced-draft cooling towers and from cooling ponds. There were three categories of measurements. (1) Ambient weather data including temperature, humidity, wind speed and wind direction. These measurements ...

  10. 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.

  11. Cooling towers for thermal power plants

    International Nuclear Information System (INIS)

    After a brief recall on cooling towers testing and construction, this paper presents four examples of very large French nuclear power plant cooling towers, and one of an Australian thermal power plant

  12. 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...

  13. 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

  14. 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

  15. Upgrading the seismic performance of the interior water pipe supporting system of a cooling tower

    International Nuclear Information System (INIS)

    This paper presents results from a numerical study that was performed in order to simulate the seismic behavior of the interior support system of the piping and cooling features of a cooling tower in one of the old power stations located in an area at the North-Western part of Greece. This cooling tower has a diameter of 60 m and a height of 100 m. The interior piping support system consists mainly of a series of nine-meter high pre-cast vertical columns made by pre-stressed concrete; these columns, together with reinforced concrete pre-cast horizontal beams that are joined monolithically with the columns at their top, form the old interior supporting system. This system represented a very flexible structure, a fact that was verified from a preliminary numerical analysis of its seismic behavior. The maximum response to the design earthquake levels resulted in large horizontal displacements at the top of the columns as well as overstress to some of the columns. The most important part of the current numerical investigation was to examine various strengthening schemes of the old interior support system and to select one that will demonstrate acceptable seismic behavior. (authors)

  16. 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...

  17. 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.)

  18. 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

  19. 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.)

  20. 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.

  1. Emergency-shutdown cooling towers: considerations in the evolution of optimum tower design

    International Nuclear Information System (INIS)

    The article discusses the various regulatory requirements and criteria governing the design of emergency-shutdown cooling towers for nuclear power plants. The effects of key tower parameters (e.g., wet-bulb temperature, flow rates, and heat load) on tower size and their interactions with system and safety requirements are explored. The evolution of the Seabrook station tower and its relationship to a companion cooling-water source (the Atlantic Ocean) are presented as an example of optimum tower/system design that complies with regulatory requirements

  2. 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

  3. Climatic impacts of nuclear power plant cooling towers

    International Nuclear Information System (INIS)

    The problems are discussed relating to the impact of waste heat from cooling towers of nuclear power plants on the energy balance in the atmosphere. The potential impacts from the release of waste heat and water from wet cooling towers into the ambient atmosphere are given. (B.S.)

  4. Vortex-augmented cooling tower-windmill combination

    Science.gov (United States)

    McAllister, Jr., John E. (Aiken, SC)

    1985-01-01

    A cooling tower for cooling large quantities of effluent water from a production facility by utilizing natural wind forces includes the use of a series of helically directed air inlet passages extending outwardly from the base of the tower to introduce air from any direction in a swirling vortical pattern while the force of the draft created in the tower makes it possible to place conventional power generating windmills in the air passages to provide power as a by-product.

  5. The corrosion behaviour of galvanized steel in cooling tower water containing a biocide and a corrosion inhibitor.

    Science.gov (United States)

    Minno?, Bihter; Ilhan-Sungur, Esra; Çotuk, Ay??n; Güngör, Nihal Do?ruöz; Cansever, Nurhan

    2013-01-01

    The corrosion behaviour of galvanized steel in cooling tower water containing a biocide and a corrosion inhibitor was investigated over a 10-month period in a hotel. Planktonic and sessile numbers of sulphate reducing bacteria (SRB) and heterotrophic bacteria were monitored. The corrosion rate was determined by the weight loss method. The corrosion products were analyzed by energy dispersive X-ray spectroscopy and X-ray diffraction. A mineralized, heterogeneous biofilm was observed on the coupons. Although a biocide and a corrosion inhibitor were regularly added to the cooling water, the results showed that microorganisms, such as SRB in the mixed species biofilm, caused corrosion of galvanized steel. It was observed that Zn layers on the test coupons were completely depleted after 3 months. The Fe concentrations in the biofilm showed significant correlations with the weight loss and carbohydrate concentration (respectively, p < 0.01 and p < 0.01). PMID:23439037

  6. 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.

  7. 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

  8. 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

  9. 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

  10. Kaiseraugst nuclear power station: meteorological effects of the cooling towers

    International Nuclear Information System (INIS)

    Considerations of water conservation persuaded the German Government in 1971 not to allow the use of the Aar and Rhine for direct cooling of nuclear power stations. The criticism is often made that the Kaiseraugst cooling towers were built without full consideration of the resulting meteorological effects. The criticism is considered unjustified because the Federal Cooling Tower Commission considered all the relevant aspects before making its recommendations in 1972. Test results and other considerations show that the effect of the kaiseraugst cooling towers on meteorological and climatic conditions is indeed minimal and details are given. (P.G.R.)

  11. 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

  12. 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.)

  13. 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

  14. Ozone inhibits corrosion in cooling towers

    Science.gov (United States)

    French, K. R.; Howe, R. D.; Humphrey, M. F.

    1980-01-01

    Commercially available corona discharge ozone generator, fitted onto industrial cooling tower, significantly reduces formation of scales (calcium carbonate) and corrosion. System also controls growth of algae and other microorganisms. Modification lowers cost and improves life of cooling system.

  15. 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)

  16. 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.)

  17. 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...

  18. 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

  19. The possibility of the free cooling with cooling towers according to a study of the actual conditions of cooling towers

    International Nuclear Information System (INIS)

    This paper reports that based on the results of a study that was conducted in winter on the state of a combined refrigerating machine and cooling tower refrigeration system in an existing large-scale DHC facility, heat load valuations and the actual performance of the cooling towers were quantitatively obtained, based on which the possibility of free cooling, from which energy savings can be expected, was verified. Based on an analysis of the relationship of the circulating water in the cooling tower during free cooling, to the outlet water temperature and the heat load, it was determined that, during a typical winter period, 850 m3/h of circulating water would be needed to remove a heat load equivalent to the manufacturing heat load from the refrigerating machines. In free cooling with 850 m3/h of circulating water, the outlet water temperature is 8.2 degrees C, or about 1.3 times as high as the outlet water temperature from the refrigerating machines. However, due to lower thermal unit of free cooling, an energy savings of about 60% can be achieved

  20. Distribution of sequence-based types of legionella pneumophila serogroup 1 strains isolated from cooling towers, hot springs, and potable water systems in China.

    Science.gov (United States)

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

    2014-04-01

    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 discrimination [IOD], 0.711), 19 STs (IOD, 0.934), and 3 STs (IOD, 0.151), respectively. The genetic variation among the potable water isolates was lower than that among cooling tower and hot spring isolates. ST1 was the predominant type, accounting for 49.4% of analyzed strains (n = 81), followed by ST154. With the exception of two strains, all potable water isolates (92.3%) belonged to ST1. In contrast, 53.1% (51/96) and only 14.3% (6/42) of cooling tower and hot spring, respectively, isolates belonged to ST1. There were differences in the distributions of clone groups among the water sources. The comparisons among L. pneumophila strains isolated in China, Japan, and South Korea revealed that similar clones (ST1 complex and ST154 complex) exist in these countries. In conclusion, in China, STs had several unique allelic profiles, and ST1 was the most prevalent sequence type of environmental L. pneumophila serogroup 1 isolates, similar to its prevalence in Japan and South Korea. PMID:24463975

  1. 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

  2. Different types of cooling towers influence the design and the conditions of the inlet of cooling water pumps

    International Nuclear Information System (INIS)

    Possible solutions of performance and number of cooling water pumps to be installed for 300 mw conventional to 2000 mw nuclear unit powers are shown. As four influencing parameters greatly vary, each pump is individually manufactured. The specific fast-running pumps are sensitive to disturbances on the suction side. 11 examples for the useful shape of chambers and arched beams of the inlet building are given according to their importance. Characteristic and proved inlet chamber types were determined by electron-analog tests and model tests. What one understands by non-destructive flow to the pumps, is determined by means of four criteria, e.g. cavitation and NPSH value (net positive suction head) or according to DIN 'Haltedruckhoehe'. As all four criteria cannot be fulfilled to a maximum, one must be able to decide between them. The constructions of cooling water pumps, pipe and spiral casing with variation are treated in nine examples. Finally, the types of control are discussed. Construction and fabrication of a single cooling pump for a 1300 mw unit would be possible today; pressure joints diameter 4500 mm. (orig.)

  3. Experimental study of cooling tower performance using ceramic tile packing

    Directory of Open Access Journals (Sweden)

    Ramkumar Ramkrishnan

    2013-03-01

    Full Text Available Deterioration of the packing material is a major problem in cooling towers. In this experimental study ceramic tiles were used as a packing material. The packing material is a long life burnt clay, which is normally used as a roofing material. It prevents a common problem of the cooling tower resulting from corrosion and water quality of the tower. In this study, we investigate the use of three different types of ceramic packings and evaluate their heat and mass transfer coefficients. A simple comparison of packing behaviour is performed with all three types of packing materials. The experimental study was conducted in a forced draft cooling tower. The variations in many variables, which affect the tower efficiency, are described.

  4. 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

  5. Design Of Cooling Tower And Standard Of Technical Test

    International Nuclear Information System (INIS)

    This book deals with types, structure and characteristic of cooling tower, design of cooling system like theory of cooling tower, similarity between heat transfer and mass transfer, basic of mass transfer, a system of measuring of cooling tower, theory of cross flow cooling tower, condition on design of cooling system outdoor air, material such as kinds of filling, performance and characteristic of filling, installation of cooling tower, management of operation of cooling tower, test method like procedure, condition and term, measurement, result report, assessment and cooling tower of natural draft.

  6. Hybrid cooling tower Neckarwestheim 2 cooling function, emission, plume dispersion

    International Nuclear Information System (INIS)

    The fan-assisted hybrid cooling tower of the 1300 MW power plant Gemeinschafts-Kernkraftwerk Neckarwestheim 2 was designed and constructed based on results from theoretical and experimental studies and experiences from a smaller prototype. The wet part acts in counterflow. The dry part is arranged above the wet part. Each part contains 44 fans. Special attention was payed to the ducts which mix the dry into the wet plume. The cooling function and state, mass flow and contents of the emission were measured. The dispersion of the plume in the atmosphere was observed. The central results are presented in this paper. The cooling function corresponds to the predictions. The content of drifted cooling water in the plume is extremely low. The high velocity of the plume in the exit causes an undisturbed flow into the atmosphere. The hybrid operation reduces visible plumes strongly, especially in warmer and drier ambient air

  7. Cooling tower fill fouling control in a geothermal power plant

    Energy Technology Data Exchange (ETDEWEB)

    Yu, F.P.; Ginn, L.D.; McCoy, W.F. [Nalco Chemical Co., Naperville, IL (United States); Castanieto, H. [CalEnergy Operating Co., Calipatria, CA (United States)

    1998-12-31

    Since its first introduction to the market in the 1970s, cooling tower film fill technology has significantly increased thermal performance and reduced the size of cooling towers. However, the narrow spaces between film fill sheets make them susceptible to fouling. Without proper chemical treatment, deposits can accumulate within the film fill resulting in reduced tower efficiency, increased fouling and plugging of the fill. These phenomena could eventually lead to collapse of the tower structure, This paper describes a new approach to remedy the high efficiency film fill fouling problem in a geothermal power plant. The plant has a long history of fill fouling problems due to a very complex make-up water chemistry and desert-related environmental conditions. In recent years, various biocide and biodispersant treatments have significantly improved fouling control by slowing down tower fill deposition rates. However, no program has been successful in reducing fill weights, especially during the summer months. Within six weeks after starting a new control program, the average weight of the tower fill deposits dropped 22% and thermal performance of the cooling tower increased 20%. The treatment resulted in significant improvements in cooling tower operation and power production efficiency.

  8. Causes and control of cooling tower film fill deposits

    International Nuclear Information System (INIS)

    Plastic film-type cooling tower fill material is used throughout the utility industry because of its excellent cooling capabilities, compact design, and durability. The remarkable heat rejection of these so-called high efficiency fill materials is due to its ability to form a film of water on a tremendous surface area. For example, hot (80-100 degrees F) recirculating water that is distributed over the cooling tower can be cooled up to 30 degrees with only a 3-4 feet depth of this fill material. By contrast, conventional splash bar cooling tower fill acts by forming droplets can require a volume many times that of film fill to achieve the same drop in cooling water temperature. This paper reports that over the past several years, the utility industry has learned that these high efficiency cooling tower fill materials are subject to fouling, despite the manufacturer or subtle differences in fill design. With certain types of makeup water quality and tower operating practices, it is sometimes impossible to avoid fouling the fill without chemical treatments to control the progression of deposit formation

  9. The effect of evaporation losses in the analysis of crossflow cooling towers

    International Nuclear Information System (INIS)

    The Merkel method for the thermal design of counterflow and crossflow cooling towers neglects the variation of the water flow from the tower inlet to outlet. It has been shown that neglecting the water evaporation losses introduces inaccuracies in the performance calculation of counterflow cooling towers. This study develops a method for including these evaporation losses and demonstrates that the error in the Merkel method for crossflow cooling towers may reach 20% depending on the design conditions. (Auth.)

  10. 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...

  11. Dry cooling tower operating experience in the LOFT reactor

    International Nuclear Information System (INIS)

    A dry cooling tower has been uniquely utilized to dissipate heat generated in a small experimental pressurized water nuclear reactor. Operational experience revealed that dry cooling towers can be intermittently operated with minimal wind susceptibility and water hammer occurrences by cooling potential steam sources after a reactor scram, by isolating idle tubes from the external atmosphere, and by operating at relatively high pressures. Operating experience has also revealed that tube freezing can be minimized by incorporating the proper heating and heat loss prevention features

  12. Dry cooling tower operating experience in the LOFT reactor

    Energy Technology Data Exchange (ETDEWEB)

    Hunter, J.A.

    1980-01-01

    A dry cooling tower has been uniquely utilized to dissipate heat generated in a small experimental pressurized water nuclear reactor. Operational experience revealed that dry cooling towers can be intermittently operated with minimal wind susceptibility and water hammer occurrences by cooling potential steam sources after a reactor scram, by isolating idle tubes from the external atmosphere, and by operating at relatively high pressures. Operating experience has also revealed that tube freezing can be minimized by incorporating the proper heating and heat loss prevention features.

  13. 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

  14. Solution and scope of utilization of the cross-stream cooling towers

    International Nuclear Information System (INIS)

    Technical solutions and operational properties of the cross-stream cooling towers as well as the scope of their utilization are presented. The differences within thermodynamic calculations of the cross-stream and counter-stream cooling towers due to the direction of the air flow as well as water flow in sprinkling system are discussed. The assessment of the capital and operational costs of the cross-stream cooling towers is given and compared with the cost of counter-stream cooling towers (utilizing as an example a calculation conducted for the cooling towers of the 720, 1100 and 1400 MW units). (author). 6 refs, 9 figs

  15. MATHEMATICAL MODELING OF EMISSIONS FROM COOLING TOWERS USING COAL GASIFICATION WASTEWATER

    Science.gov (United States)

    The report describes a computer program that calculates atmospheric emissions from counterflow cooling towers when using pretreated coal gasification wastewaters as tower makeup water. Air stripping and biological oxidation are both incorporated into the mathematical model as pos...

  16. 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.)

  17. Response of cooling towers to wind loads

    Directory of Open Access Journals (Sweden)

    G. Murali

    2012-01-01

    Full Text Available This paper deals with the study of two cooling towers of 122 m and 200 m high above ground level. These cooling towers have been analysed for wind loads using ANSYS software by assuming fixity at the shell base. The wind loads on these cooling towers have been calculated in the form of pressures by using the circumferentially distributed design wind pressure coefficients as given in IS: 11504 - 1985 code [1] along with the design wind pressures at different levels as per IS:875 (Part 3 - 1987 code [2]. The analysis has been carried out using 8-noded shell element (SHELL 93 with 5 degrees of freedom per node. The results of the analysis include membrane forces, viz., meridional force (Nf and hoop force (Nq, and bending moments, viz., meridional moment (Mf and hoop moment (Mq. The vertical distribution of membrane forces and bending moments along 0o and 70o meridians and the circumferential distributions at base, throat and top levels have been studied for both the cooling towers. For circumferential distribution, non-dimensional values have been obtained by normalizing the membrane forces and bending moments using the reference values at 0o meridian. Similarly, the reference values at the base have been used for vertical distribution. These non-dimensional curves for both the cooling towers have been compared in the present study for the feasibility of any generalisation.

  18. 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

  19. 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.

  20. 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

  1. 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.

  2. 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...

  3. 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.)

  4. On the construction of cooling towers in FRG

    International Nuclear Information System (INIS)

    The background of cooling tower construction in Federal Republic of Germany is briefly outlined. The main types of cooling towers used in TPP and NPP cooling systems, design of structural elements, erection methods and prospects of cooling tower construction in FRG are described

  5. 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

  6. 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)

  7. 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)

  8. Water-saving and environmentally-minded utilization of waste heat as a substitute for cooling towers-Agrotherm

    Energy Technology Data Exchange (ETDEWEB)

    Reinken, G.

    1981-07-01

    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.

  9. 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

  10. Piers cooling towers. From first idess to realizations

    International Nuclear Information System (INIS)

    After a first part consecrated at the historical aspect of vertical piers cooling towers the second part indicates the experience pulled of the Chooz and Golfech cooling towers conception and realization

  11. FIELD INVESTIGATIONS OF MECHANICAL DRAFT COOLING TOWER PLUMES

    Science.gov (United States)

    Tethered Kitoon (small blimp) sampling techniques were devised to measure the distribution of temperature and humidity in the invisible portion of power plant cooling tower plumes from both single cell and multiple cell cooling towers under several conditions. These measurements,...

  12. Experiences with a parametrised cooling-tower plume model

    International Nuclear Information System (INIS)

    The model describes the effect of cooling tower plumes of smoke, e.g. superimposed from two circular cooling towers, on the ambient climate. It may be extended to the possibility of simulating cell coolers. (DG)

  13. 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

  14. 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…

  15. 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)

  16. Change structure of cooling towers with deletion cellulose pads (packing) and air blower and use vacuum mechanism

    OpenAIRE

    MOSTAGHELCHI, Mahdi; MIRJALILY, Seyyed Ali Agha; OLOOMI, Seyyed Amir Abbass

    2015-01-01

    Abstract. Topics studied in this project are to change the structure of wet cooling towers that are used in refrigerating industry. Base of working in all existing wet cooling is on upgrading heat exchange between air and cooling liquid and increasing surface evaporation and more contact between water and air. Generally, in cooling towers heated water by pipes is moved to the top of the tower. In this route water has heat exchange ventilator with outgoing air, is cooled and collected in botto...

  17. Analytical Assessment of Environmental Impact for APR1400DC UHS Cooling Tower

    International Nuclear Information System (INIS)

    Hot process water is pumped from the plant process to the cooling towers. Heat is rejected through evaporation of the process water, interacting with ambient air blown upward by fans.. Plumes generated from exit ports of the cooling tower may have adverse effects on the environment, such as deposition of cooling tower drift release, fogging, icing, shadowing, and ground-level temperature and humidity increase. These kinds of environmental impact of the cooling tower are linked closely with the dispersion of the cooling tower plumes. In this respect, predicting the behavior of the plumes has become one of the most important issues in the environmental assessments of the cooling towers. The SACTI (seasonal/annual cooling tower impact) model is an analytical tool to predict the environmental effect of cooling tower, which was developed by Argonne National Laboratory and University of Illinois with support from EPRI (electric power research institute). The initial version of SACTI has been widely used to assess the environmental effect of cooling towers in many industrial fields such as steam power plants and NPPs. Guo et. al. investigated impact of heat rejection and cooling tower height on plume dispersion using the SACTI model, for the purpose of the future construction of inland NPPs. They found that increasing cooling tower height decreases the plume length and height frequencies. Their simulation results showed that the increase in heat rejection increases the plum radius frequency. The APR1400DC is an advanced light water reactor developed for the purpose of NRC-DC (design certification). The cooling towers for APR1400DC UHS consist of two linear mechanical draft cooling towers (LMDCTs). The LMDCT for APR1400DC UHS is conceptually designed because the plant site has not been decided yet. In the present study, the dependency of plume dispersion on the number of cooling towers is investigated using SACTI-2-beta, for predicting annual environmental effect of APR1400DC LMDCT. In the present study, annual/seasonal impacts of cooling towers for APR1400DC are analyzed using SACTI model. The main conclusions are as follows: 1. Increasing the number of cooling towers increases the level of plume length frequency and plume shadowing frequency. However, variation of exit port height has less effect on them. 2. The areas of plume-induced fogging and icing are enlarged with increase in the number of cooling towers

  18. European dry cooling tower operating experience

    Energy Technology Data Exchange (ETDEWEB)

    DeSteese, J.G.; Simhan, K.

    1976-03-01

    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.

  19. 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

  20. 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

  1. 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.

  2. 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.

  3. 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

  4. 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)

  5. 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.

  6. A New Algorithm for Optimum Design of Mechanical Draft Wet Cooling Towers

    Directory of Open Access Journals (Sweden)

    A. Ataei

    2009-01-01

    Full Text Available The present study describes the designing of a thermally and economically optimum mechanical draft counter-flow wet cooling tower. The design model allows the use of a variety of packing materials in the cooling tower toward optimizing heat transfer. The design model incorporated the cooling tower factors to achieve the optimum design. The main factors included: the diameter of the water droplets, the liquid to gas mass ratio, the height of rain zone, packing zone and spray zone, the air and water velocity inside the tower and the frontal area. Once the optimum packing type is chosen, a compact cooling tower with low fan power consumption is modelled within the known design variables. The optimization model is validated against a sample problem. The suggested design algorithms of cooling tower are computed using Visual Studio.Net 2003 (C++.

  7. 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)

  8. 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...

  9. 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.)

  10. Structural problems in the construction of natural draught cooling towers

    International Nuclear Information System (INIS)

    The paper deals with the structural requirements and development possibilities for large cooling towers, and in particular discusses parameter investigations into the reinforcement of cooling tower shells and problems of optimisation. In conclusion proposals are made as to how concrete cooling towers of very large dimensions reinforced with steel, as for example are required in dry cooling for large capacity plant, can be developed economically. (orig.)

  11. COOLING CONDENSERS WITH COLD AIR FLOW OR AIR ELIMINATION IN POWER PLANT TOWERS

    OpenAIRE

    ZADEH, Hemmat Mahmoud

    2015-01-01

    Abstract. Evaporative cooling mechanism and specific heat exchange are principles of cooling happening in towers. Air/water mixture releases enthalpy of vaporization. Vapor rises from consumed hot water to cold air flow and water evaporation energy is 1000 Btu per kilogram. This endothermic process from water decreases water temperature. Water loss is the drawback of this process which enters the air from tower in the form of vapor. The vapor is approximately 1.2 percent for each 5.5 Centigra...

  12. Rainfall enhancement due to scavenging of cooling tower condensate

    International Nuclear Information System (INIS)

    The recent increase in the number of electrical generating plants that use cooling towers and projections for further expansion have prompted considerable concern about the environmental impact of large releases of energy and water effluent. One aspect of a comprehensive research program, Meteorological Effects of Thermal Energy Releases (METER), is an examination of the physical effects of the vast amounts of water vapor and condensate (tens of thousands of kilograms per second) regularly released by modern cooling towers. Such large releases can significantly affect water vapor and cloud-related natural processes, at least in the immediate vicinity. The question of precipitation scavenging of condensate droplets by natural precipitation and the resultant enhancement of precipitation under the plume is considered theoretically

  13. 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.

  14. 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.

  15. 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.)

  16. 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.)

  17. 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

  18. Cooling tower shell and mechanical or draft cooling tower with a such shell

    International Nuclear Information System (INIS)

    The shell is for thermal power plants cooling towers having heat exchange surfaces inside the tower. The vertical is such that the hydraulic diameter D in each horizontal section, at a level z above a reference section of which hydraulic diameter is Do is between once and 1.15 time the value given by the formula: Do(1+(2δρgz/ρVo2))O,25 + 2εz in which Vo is the vertical flow rate through the reference section; ρ is the hot air density; δρ is the density difference of the hot air between the outside and the inside of the shell; ε is an adjustment parameter without dimension of which value is between 0.09 and 0.13. The present invention ensures the cooling tower to operate nearly at the optimum and the construction cost of the shell is reduced

  19. 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...

  20. 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

  1. 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

  2. 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

  3. 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

  4. Experimental study on the thermal performance of a mechanical cooling tower with different drift eliminators

    International Nuclear Information System (INIS)

    Cooling towers are equipment devices commonly used to dissipate heat from power generation units, water-cooled refrigeration, air conditioning and industrial processes. Water drift emitted from cooling towers is objectionable for several reasons, mainly due to human health hazards. It is common practice to fit drift eliminators to cooling towers in order to minimize water loss from the system. It is foreseeable that the characteristics of the installed drift eliminators, like their pressure drop, affect the thermal performance of the cooling tower. However, no references regarding this fact have been found in the reviewed bibliography. This paper studies the thermal performance of a forced draft counter-flow wet cooling tower fitted with different drift eliminators for a wide range of air and water mass flow rates. The data registered in the experimental set-up were employed to obtain correlations of the tower characteristic, which defines the cooling tower's thermal performance. The outlet water temperature predicted by these correlations was compared with the experimentally registered values obtaining a maximum difference of ±3%

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

    Science.gov (United States)

    Abedi-Nik, Farhad; Sabouri-Ghomi, Saeid

    2008-07-01

    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.

  6. 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

  7. 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.

  8. Large wet-type cooling towers and their influence on the environment

    International Nuclear Information System (INIS)

    Large wet-type cooling towers with natural draft are said to be ecologically beneficial today, especially concerning the heat emission from power plants. A description is given of the influence of such cooling towers on the environment and the possible climatic influences are considered in detail. Recent investigations have shown that wet-type cooling towers represent no danger of any kind for fauna and flora as to the bacterial radiation. Physical studies have shown that neither the emitted water vapour nor the heat emitted into the atmosphere, can significantly change the macroclimate and microclimate. At present, wet-type cooling towers cannot be replaced by dry-type or so-called hybrid-type cooling towers, the technical development of which for large units being not yet guaranteed. (orig.)

  9. 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.

  10. Effect of chlorine and temperature on free-living protozoa in operational man-made water systems (cooling towers and hot sanitary water systems) in Catalonia.

    Science.gov (United States)

    Canals, Oriol; Serrano-Suárez, Alejandra; Salvadó, Humbert; Méndez, Javier; Cervero-Aragó, Sílvia; Ruiz de Porras, Vicenç; Dellundé, Jordi; Araujo, Rosa

    2015-05-01

    In recent decades, free-living protozoa (FLP) have gained prominence as the focus of research studies due to their pathogenicity to humans and their close relationship with the survival and growth of pathogenic amoeba-resisting bacteria. In the present work, we studied the presence of FLP in operational man-made water systems, i.e. cooling towers (CT) and hot sanitary water systems (HSWS), related to a high risk of Legionella spp. outbreaks, as well as the effect of the biocides used, i.e. chlorine in CT and high temperature in HSWS, on FLP. In CT samples, high-chlorine concentrations (7.5?±?1.5 mg chlorine L(-1)) reduced the presence of FLP by 63.8 % compared to samples with low-chlorine concentrations (0.04?±?0.08 mg chlorine L(-1)). Flagellates and amoebae were observed in samples collected with a level of 8 mg chlorine L(-1), which would indicate that some FLP, including the free-living amoeba (FLA) Acanthamoeba spp., are resistant to the discontinuous chlorine disinfection method used in the CT studied. Regarding HSWS samples, the amount of FLP detected in high-temperatures samples (53.1?±?5.7 °C) was 38 % lower than in low-temperature samples (27.8?±?5.8 °C). The effect of high temperature on FLP was chiefly observed in the results obtained by the culture method, in which there was a clear reduction in the presence of FLP at temperatures higher than 50 °C, but not in those obtained by PCR. The findings presented here show that the presence of FLP in operational man-made water systems should be taken into account in future regulations. PMID:25410311

  11. 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

  12. 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

  13. 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

  14. 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)

  15. 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

  16. Prevalence study of Simkania negevensis in cooling towers in Spain.

    Science.gov (United States)

    Pérez, Leonardo Martín; Codony, Francesc; Ríos, Karina; Adrados, Bárbara; Fittipaldi, Mariana; De Dios, Gregori; Peñuela, Gustavo; Morató, Jordi

    2011-06-01

    Simkania negevensis is an obligate intracellular bacterium grouped into the order Chlamydiales. This new amoeba-resistant intracellular bacterium might represent a novel etiologic agent of bronchiolitis and community-acquired pneumonia and occurs in aquatic habitats such as drinking water and reclaimed wastewater. Another amoeba-related bacterium, Legionella pneumophila, is an etiologic agent of pneumonia transmitted by environmental aerosols or contaminated water/air cooling systems. These transmission pathways are important in the natural history of Legionellae infections and possibly other intracellular microorganisms such as Parachlamydiaceae; thus, understanding the feasibility of Simkania infection by these routes is relevant. In the present work, we investigated the prevalence of this newly identified pathogenic bacterium in cooling towers by quantitative PCR (qPCR) and its possible relationship with Legionella pneumophila co-infection. Our results show Simkania detection in 2 of 70 cooling towers analyzed. To our knowledge, this report is the first describing Simkania negevensis detection in this category of environmental water samples. PMID:21942196

  17. 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

  18. 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

  19. Observed and predicted cooling tower plume rise at the John E. Amos Power Plant, West Virginia

    International Nuclear Information System (INIS)

    There is much current interest in cooling tower plume rise because of its importance in determining the environmental impact of cooling towers at planned power plants and industrial facilities. Some of the possible environmental problems related to heat and water emissions from cooling towers are drift deposition, ground level fog, cloud formation, and precipitation enhancement. An important factor in all of these problems is the calculation of the plume trajectory, which is often complicated by the presence of multiple sources and water phase changes in the plume. The latent heat does not strongly influence plume rise if there is no cloud present at the top of the plume. A one dimensional plume and cloud growth model was developed to study these effects. In this paper, the predictions of the model are compared with observations of cooling tower plume rise at the John E. Amos, W. Va. fossil-fuel power plant

  20. 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.)

  1. 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.)

  2. 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.)

  3. 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.)

  4. 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.

  5. 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

  6. The dry and adiabatic fluid cooler as an alternative to cooling towers: an experimental view.

    OpenAIRE

    Lucas Miralles, Manuel; Martínez Beltrán, Pedro Juan; Ruiz Ramírez, Javier; Sánchez Kaiser, Antonio; Zamora Parra, Blas; Viedma, A.

    2011-01-01

    Energy and environmental implications of a refrigeration cycle are largely conditioned by the choice of condensing system. Conventional solutions transfer heat to water, and recirculated through cooling towers or to atmospheric air through a dry condenser. While the use of cooling towers means less energy consumption due to lower pressure in the condenser, a number of environmental implications are questioning their installation. Mainly, it represents an emission of chemicals or microorganism...

  7. An improved model for the analysis of evaporative counterflow cooling towers

    International Nuclear Information System (INIS)

    A rigorous approach is applied to the thermal design of counterflow cooling towers, by obviating the six simplifying assumptions in the classical Merkel method. It is indicated that: (1) neglecting evaporation losses is the main cause of inaccuracy in the Merkel results; (2) the error in the Merkel method may reach 12%; and (3) the present solution provides a more accurate and more ecologically favorable prediction for the cooling water tower. (Auth.)

  8. Numerical simulation of cooling performance of wind tower (Baud-Geer) in hot and arid region

    Energy Technology Data Exchange (ETDEWEB)

    Kalantar, Vali [Mechanical Department of Yazd University, Yazd (Iran)

    2009-01-15

    In the present study, an attempt is made to study the cooling performance of a wind tower in a hot and dry region, Yazd, in Iran. For the relevant experiments and numerical studies, at first, the temperature and wind velocity inside and outside of the wind tower measured. Based on four-day measurements during last summer, a computer program was designed with language C{sup ++} to solve the equations. Also in the study the effects of parameters including wind tower height, variety of the materials used in the wind tower walls, the amount of vaporized water, the temperature of input and output air, the wind velocity and the relative humidity were investigated. Furthermore, to develop, a natural flow of air, for days without blowing a wind the role of solar chimney was considered. Finally, to evaluate the method of integral view and take information about streamlines of airflow in wind tower (Baud-Geer), velocity, pressure, humidity, temperature and density profile of fluid, Fluent software is applied to analyze the air flow in the wind tower in differential view for three-dimensional and steady state conditions with water spraying at the top of wind tower. The results indicate that the evaporative cooling is very effective in a hot and dry region. The temperature decreases considerably, if the wind towers are equipped with the water vaporization system. This causes the air becomes heavier and a natural motion of air through downside of wind tower to be produced. (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. On the possibility of a ''dry'' cooling tower application for the APS condensators with a dissociating coolant

    International Nuclear Information System (INIS)

    Calculations have been carried out for a Geller cooling tower of a 1000 MW nuclear power plant aimed at investigating the possibility of using ''dry'' cooling towers to cool condensers of nuclear power plants with N2O4 as coolant, and at estimating specific charges on the process water supply system. Taking into consideration commercialy produced equipment, air condenser plants are assumed to operate with an ordinary surface condenser. The main dimensional and cost parameters of a ''dry'' cooling tower for a thermal cycle version with the maximum temperature of 450 deg C are calculated using the Transelectro (Hungary) nomograms for average annual air temperature. The calculation results show the Geller cooling towers for 1000 MW nuclear power plants to be economically competitive with evaporating cooling towers; and more; besides, is this case atmosphere pollution is avoided and water flow rate for making-up the water supply system is reduced

  11. EXPERIMENTAL SIMULATION OF SINGLE AND MULTIPLE CELL COOLING TOWER PLUMES

    Science.gov (United States)

    An experimental investigation was conducted to determine the dilution characteristics of single and multiple port buoyant discharges typical of modern natural and mechanical draft cooling towers. Simultaneous measurements of velocity and tracer concentration profiles were taken a...

  12. Natural-draught cooling towers made of reinforced concrete

    International Nuclear Information System (INIS)

    Large power plant units and dry cooling tower technology require larger dimensions for natural-draught cooling towers. The main curvation radii in latitudinal and meridian direction are thus increased, which results in a lower three-dimensional support strength. This development is an incentive for constant re-consideration of calculation methods, safety philosophy, and dimensioning criteria. In this context, wind effects have been re-formulated and given a scientific foundation. Constructional measures to improve the static and dynamic behaviour of the structure have been presented and critically assessed. A cost analysis, finally, gave the most rational applications of the new shell construction with reinforcing elements. A cooling tower now under construction gave a realistic example. Fundamental aspects concerning the foundations of cooling tower shells and two special types of foundation are further points to clarify the subject. (orig./HP)

  13. Lower parts of Temelin nuclear power plant cooling towers

    International Nuclear Information System (INIS)

    The progress of work is described in detail on the foundations and lower parts of the cooling towers of the Temelin nuclear power plant. The cooling tower is placed on a reinforced concrete footing of a circular layout. Support pillars are erected on the reinforced concrete continuous footing. They consists of oblique shell stanchions. Inside, the footing joins up to monolithic wall and slab structures of the cooling tower tub. The tub bottom forms a foundation plate supporting prefab structures of the cooling tower inner structural systems. The framed support of the chimney shell consists of 56 pairs of prefabricated oblique stanchions. Following their erection into the final position and anchoring in the continuous footing, the concreting of the casing can start of the reinforced conrete chimney. (Z.M.). 3 figs

  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. 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.

  16. Methods and equipment for investigating plume discharge from atmospheric cooling systems. Application to cooling towers

    International Nuclear Information System (INIS)

    Cooling towers discharge a distinct plume with varying internal temperature, moisture and velocity distributions to atmosphere. Two possible methods of approach to this problem are: scale model tests in a water plume (usually to a geometrical scale of about 1/500); three-dimensional mathematical models with computer data-processing methods. In either case, the results care checked against field measurement data, which frequently provides complementary information

  17. Closed-type cooling system with cooling towers for modern NNPs

    International Nuclear Information System (INIS)

    Arrangement decisions and prospects of the development of closed-type cooling systems with cooling towers for modern NPPs are considered. Design solutions, process parameters, technical and economical properties of large cooling towers for 100x103 and 180x103 m3/h NPP and heat-and-power nuclear plants are presented

  18. Gust factors for hyperbolic cooling towers on soils

    Energy Technology Data Exchange (ETDEWEB)

    Wang Shu (Bochum Univ. (Germany, F.R.). Inst. fuer Konstruktiven Ingenieurbau); Lu Wenda (Shanghai Univ. of Technology (CN). Institute of Applied Mathematics and Mechanics)

    1991-01-01

    The dynamic response of hyperbolic cooling towers on soils are calculated in this paper based on a dynamic region-wise variational principle and the modes of free vibrations reported elsewhere by the authors. The spectrum method of random vibration theory and wind load data from full-scale measurements are used. Gust factors for hyperbolic cooling towers and footings on different soils are presented. (author).

  19. Rainfall enhancement due to washout of cooling tower condensate

    International Nuclear Information System (INIS)

    Theoretical calculations of the washout of cooling tower condensate droplets by frontal raindrops show that rainfall enhancement can be significant and is measurable under typical meteorological and cooling tower effluent source conditions. For the case of moderate rainfall rates and a wind speed of 5 m/sec, centerline rainfall enhancement was as much as 46%, cross-plume average enhancement as much as 7%, and distance to one-half depletion of the source 1 to 10 km

  20. 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...

  1. Improvement of the environmental and economic characteristics of cooling towers. The Periodic Cooling Tower: small scale, full scale, and surface roughening tests. Annual report, 1974--1975

    Energy Technology Data Exchange (ETDEWEB)

    Hon, P.C.; Han, J.; Pilger, P.F.; Fink, D.A.; Andeen, B.R.

    1975-06-30

    Research on the Periodic Cooling Tower is described. The Periodic Tower consists of rotating sheet metal discs partially immersed in hot, power plant condensor effluent. The tower can be either wet or dry, depending upon the amount of water carried into the air side on the plates' surface. An oil layer, floating on the water's surface is effective in eliminating water carryover. The advantages of the Periodic Tower lie in the low cost of the discs and the ability to operate dry. The work emphasized: (1) scale model flow and heat transfer tests, (2) completion of a facility for testing full sized modules, and a parametric study of the oil film thickness on the discs, and (3) construction, instrumentation, and calibration of a test apparatus to study the further enhancement of disc performance by surface roughening. (GRA)

  2. 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

  3. Cooling towers (citations from the NTIS data base). Report for 1964-August 1978

    International Nuclear Information System (INIS)

    Abstracts of Federally-funded research dealing with design and environmental impacts of wet and dry cooling towers are presented. Cooling tower drift instrumentation and thermal and chemical pollution control systems are covered. Citations primarily pertain to cooling towers used in nuclear power plants, with a few pertaining to cooling towers used in wastewater treatment

  4. 75 FR 63802 - Action Affecting Export Privileges; Parto Abgardan Cooling Towers Co.

    Science.gov (United States)

    2010-10-18

    ... of Industry and Security Action Affecting Export Privileges; Parto Abgardan Cooling Towers Co. Parto Abgardan Cooling Towers Co., P.O. Box 966, Folsom, CA 95763; and P.O. Box 19395/5478, Tehran, Iran; and No... Cooling Towers, Co. Applicable to Parto Abgardan Cooling Towers Co. Pursuant to Section 766.23 of...

  5. 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)

  6. A simulation software for cooling towers optimal operation

    Energy Technology Data Exchange (ETDEWEB)

    Damian, M.; Motoiu, I.; Caracasian, L. [Inst. of Power Studies and Design, Bucharest (Romania)

    1998-12-31

    Deregulation of power markets in Europe will facilitate competing alternatives in power supplies, more competitive energy prices and will improve customer service. The Romanian power sector is also characterized by profound transformation from old, polluting system to one reaching for efficiencies of market-driven economy. In order to reduce the production costs of combined electricity and heat generation power plants, the paper presents the software called CTO for optimization of the cross-current cooling tower`s operation. The optimum operation of the cooling tower will be that which performs the removal of the waste heat-of imposed thermal level- at a minimum specific cost. For different alternatives of the known input values and for all possible operation diagrams the cooling tower parameters are calculated through the developed software. As a result its optimum operation conditions are indicated.

  7. 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.

  8. Influence of water droplets from a cooling tower vapour cloud on the deposition of radioactive compounds from waste plumes from nuclear power stations

    International Nuclear Information System (INIS)

    Vapour clouds from cooling towers contain in their visible part condensation droplets which rarely exceed a total quantity of 3g/m3. The diameter of these droplets is on average 10 ?m. They can only reach the ground if they are trapped by coalescence with raindrops passing through the cloud and entrained in their downward path. If the radioactive waste air plume becomes mixed with the visible part of the vapour cloud from the cooling tower, the condensation droplets can easily acquire radioactive contamination, resulting during rainy weather in a deposition of radioactive emissions from the chimney, the level of which will vary appreciably from that obtained without any mixing of the waste air plume with the vapour cloud. Some of the drops of spray emitted by the cooling tower may also reach the ground in view of their greater size (up to a few 100 ?m). They will only have a radioactive content, if they pass through the waste air plume. The short-term deposition rate is discussed: from washout coefficients which are derived, calculations are made of the short-term deposition of gaseous iodine. The long-term effects (i.e. accumulation of deposited iodine at a particular point) are also discussed. (U.K.)

  9. Evaluation of the RSG-GAS cooling tower performance

    International Nuclear Information System (INIS)

    Utilization of RSG-GAS reactor should be operated as efficiently as possible, so that reactor operation planning using one line primary coolant can be anticipated. To analyze the performance of the RSG-GAS cooling tower with one line primary coolant doing by using same data from 10 MW thermal reactor operation. The result were then compare to those achieved using CATHENA code. The results indicated that, for design condition the ratio of water flowrate to air is (L/G) 1.52 and number transfer unit (NTU) is 0.348. For operation condition, the average of L/G and NTU are respectively 1.37 and 0,348. Moreover the results achieved by the code showed that L/G and NTU are respectively 1.35 and 0,302. The performance of cooling tower achieved operation condition and the code results are respectively 91% and 72%. This means that the calculated results are lower than measurement results

  10. 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

  11. Potentially pathogenic amoeba-associated microorganisms in cooling towers and their control.

    Science.gov (United States)

    Pagnier, Isabelle; Merchat, Michèle; La Scola, Bernard

    2009-06-01

    Cooling towers provide a favorable environment for the proliferation of microorganisms. Cooling towers generate a biofilm and often aerosolize contaminated water, thereby increasing the risk of microorganism dissemination by human inhalation. This pathogen dissemination was first revealed by the epidemics of Legionnaires' disease that were directly related to the presence of cooling towers, and since then, the ecology of Legionella pneumophila has been well studied. Each country has specific standards regarding the acceptable amount of microorganisms in cooling tower systems. However, those standards typically only concern L. pneumophila, even though many other microorganisms can also be isolated from cooling towers, including protozoa, bacteria and viruses. Microbiological control of the cooling tower system can be principally achieved by chemical treatments and also by improving the system's construction. Several new treatments are being studied to improve the efficiency of disinfection. However, as most of these treatments continue to focus solely on L. pneumophila, reports of other types of pathogens continue to increase. Therefore, how their dissemination affects the human populous health should be addressed now. PMID:19492970

  12. 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

  13. 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.

  14. 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.

  15. 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)

  16. Predicted climatology of cooling tower plumes from energy centers

    International Nuclear Information System (INIS)

    A one-dimensional plume and cloud growth model is applied to four months of radiosonde observations from Nashville, using as initial conditions the plume from single large cooling towers with waste heat outputs of 103, 104 and 105 MW, and a complex of cooling towers with a total waste heat output of 105 MW. Estimates of average annual plume rise from the four energy sources are 580, 1180, 2460 and 780 m, respectively.The predicted plume rise, visible plume length and cloud formation are given as functions of time of day, year and weather type. For example, a cloud forms at the top of the plume from the 103 MW tower in 65% of the morning soundings during which ground level fog was observed. A cloud is predicted to occur 95% of the time at the top of the plume from the single 105 MW tower. It is found that if the towers in an energy center are separated by a distance greater than the average plume rise from one tower, then plume merging is minimized. Observations from TVA's Paradise steam plant are used to test the predictions of visible plume length from a single 103 MW tower

  17. Cooling towers for 1000 MW nuclear power unit

    International Nuclear Information System (INIS)

    The project is discussed of one single cooling tower with natural draft for one nuclear power plant unit. Two towers are designed for one unit of the Temelin power plant and the construction of one single tower for one unit is being considered. A brief economic analysis is made on the basis of experience and foreign data, and a comparison made with Czechoslovak projects. The use of a single tower will save 20% of capital costs and further savings will be achieved in the pipelines and built-up area. The relative cost of the tower depends on the temperature of ambient air, the dimensions of the tower, on shower intensity. There are also considerable differences in power generation with constant heat consumption. Briefly presented is the procedure of the calculation of deviations in power generation from rated states, which are the basis for economic evaluation and the choice of the optimal variant of cooling towers. (M.D.). 8 figs., 2 tabs., 6 refs

  18. 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

  19. 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...

  20. Cooling towers. A bibliography, March 1976--May 1977

    International Nuclear Information System (INIS)

    Included are 485 citations to references on cooling towers for fossil-fuel or nuclear power plants. A few citations are included on other types of condenser cooling systems, e.g., cooling ponds and canals. The citations were taken from the ERDA Energy Information Data Base (EDB) covering the approximate period March 1976 to May 1977. Corporate, Personal Author, Subject, and Report Number indexes are provided

  1. Influences of height to diameter ratios of dry-cooling tower upon thermo-flow characteristics of indirect dry cooling system

    International Nuclear Information System (INIS)

    Ambient winds may reduce the cooling efficiency of a nature draft dry-cooling tower, so it is of benefit to the design and operation of indirect dry cooling system to determine the preferred tower shape to restrain the adverse impacts of ambient winds. Based on the dry-cooling tower with vertically arranged heat exchanger bundles around the circumference, air-side flow and heat transfer models are developed for three typical height to diameter ratios of tower. The velocity, pressure and temperature fields of cooling air in the absence and presence of ambient winds are presented, and the mass flow rate, heat rejection and outlet water temperature of each sector and air-cooled heat exchangers are calculated. The results show that the dry-cooling tower with a low height to diameter ratio is superior to that with a high ratio in thermo-flow performances of indirect dry cooling system at high wind speeds on condition that the air-cooled heat exchangers have the same heat transfer surface areas. At low wind speeds, the mass flow rate and heat rejection of air-cooled heat exchanger vary little with height to diameter ratios of tower due to almost the same buoyancy forces. It is recommended to take a low height to diameter ratio of tower, especially at strong ambient winds for better thermo-flow performances of indirect dry cooling system. (authors)

  2. 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)

  3. Tower Water-Vapor Mixing Ratio

    Energy Technology Data Exchange (ETDEWEB)

    Guastad, Krista; Riihimaki, Laura; none,

    2013-04-01

    The purpose of the Tower Water-Vapor Mixing Ratio (TWRMR) value-added product (VAP) is to calculate water-vapor mixing ratio at the 25-meter and 60-meter levels of the meteorological tower at the Southern Great Plains (SGP) Central Facility.

  4. Modeling of hydronic radiant cooling of a thermally homeostatic building using a parametric cooling tower

    International Nuclear Information System (INIS)

    Highlights: • Investigated cooling of thermally homeostatic buildings in 7 U.S. cities by modeling. • Natural energy is harnessed by cooling tower to extract heat for building cooling. • Systematically studied possibility and conditions of using cooling tower in buildings. • Diurnal ambient temperature amplitude is taken into account in cooling tower cooling. • Homeostatic building cooling is possible in locations with large ambient T amplitude. - Abstract: A case is made that while it is important to mitigate dissipative losses associated with heat dissipation and mechanical/electrical resistance for engineering efficiency gain, the “architect” of energy efficiency is the conception of best heat extraction frameworks—which determine the realm of possible efficiency. This precept is applied to building energy efficiency here. Following a proposed process assumption-based design method, which was used for determining the required thermal qualities of building thermal autonomy, this paper continues this line of investigation and applies heat extraction approach investigating the extent of building partial homeostasis and the possibility of full homeostasis by using cooling tower in one summer in seven selected U.S. cities. Cooling tower heat extraction is applied parametrically to hydronically activated radiant-surfaces model-buildings. Instead of sizing equipment as a function of design peak hourly temperature as it is done in heat balance design-approach of selecting HVAC equipment, it is shown that the conditions of using cooling tower depend on both “design-peak” daily-mean temperature and the distribution of diurnal range in hourly temperature (i.e., diurnal temperature amplitude). Our study indicates that homeostatic building with natural cooling (by cooling tower alone) is possible only in locations of special meso-scale climatic condition such as Sacramento, CA. In other locations the use of cooling tower alone can only achieve homeostasis partially

  5. Disinfection of bacterial biofilms in pilot-scale cooling tower systems.

    Science.gov (United States)

    Liu, Yang; Zhang, Wei; Sileika, Tadas; Warta, Richard; Cianciotto, Nicholas P; Packman, Aaron I

    2011-04-01

    The impact of continuous chlorination and periodic glutaraldehyde treatment on planktonic and biofilm microbial communities was evaluated in pilot-scale cooling towers operated continuously for 3 months. The system was operated at a flow rate of 10,080 l day(-1). Experiments were performed with a well-defined microbial consortium containing three heterotrophic bacteria: Pseudomonas aeruginosa, Klebsiella pneumoniae and Flavobacterium sp. The persistence of each species was monitored in the recirculating cooling water loop and in biofilms on steel and PVC coupons in the cooling tower basin. The observed bacterial colonization in cooling towers did not follow trends in growth rates observed under batch conditions and, instead, reflected differences in the ability of each organism to remain attached and form biofilms under the high-through flow conditions in cooling towers. Flavobacterium was the dominant organism in the community, while P. aeruginosa and K. pneumoniae did not attach well to either PVC or steel coupons in cooling towers and were not able to persist in biofilms. As a result, the much greater ability of Flavobacterium to adhere to surfaces protected it from disinfection, whereas P. aeruginosa and K. pneumoniae were subject to rapid disinfection in the planktonic state. PMID:21547755

  6. 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.

  7. A case of nosocomial Legionella pneumonia associated with a contaminated hospital cooling tower.

    Science.gov (United States)

    Osawa, Kayo; Shigemura, Katsumi; Abe, Yasuhisa; Jikimoto, Takumi; Yoshida, Hiroyuki; Fujisawa, Masato; Arakawa, Soichi

    2014-01-01

    We report the epidemiological investigation of a nosocomial pneumonia case due to Legionella pneumophila linked to a contaminated hospital cooling tower in an immune-compromised patient. A 73-year-old female patient was diagnosed with nosocomial Legionella pneumonia proven by a culture of L. pneumophila serogroup 1 from bronchoalveolar lavage fluid. Two strains isolated from the patient and two strains isolated from two cooling towers were found to be identical using repetitive-sequence-based-PCR with a 95% probability. This Legionella pneumonia case might be caused by aerosol from cooling towers on the roof of the hospital building which was contaminated by L. pneumophila. We increased up the temperature of hot water supply appropriately for prevention of Legionella breeding in an environment of patients' living. On the other hand, as the maintenance of cooling tower, we increased the frequency of Legionella culture tests from twice a year to three times a year. In addition, we introduced an automated disinfectants insertion machine and added one antiseptic reagent (BALSTER ST-40 N, Tohzai Chemical Industry Co., Ltd., Kawasaki, Japan) after this Legionella disease, and thereafter, we have no additional cases of Legionella disease or detection of Legionella spp. from the cooling tower or hot water supply. This case demonstrates the importance of detecting the infection source and carrying out environmental maintenance in cooperation with the infection control team. PMID:24462430

  8. Successful implementation of ageing management exemplified at the cooling tower of the Emsland nuclear power plant

    International Nuclear Information System (INIS)

    The paper describes the successful implementation of the restoration of water distribution channels at the cooling tower of the Emsland nuclear power plant under the aspect of ageing management. The main challenge of ageing management is the determination of potential ageing mechanism and to avoid systematically and effectively their damaging influences. In the course of the annual site inspections, abnormalities at the lower side of the water-distribution channels of the cooling tower were detected, analysed, and repaired. The procedures conserve the load bearing reinforcement only for a certain period. Therefore permanent structural monitoring is needed. (orig.)

  9. 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)

  10. 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.)

  11. 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

  12. 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

  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. Effects of thermal discharges from large cooling towers

    International Nuclear Information System (INIS)

    The results can be summarized as follows: Direct effects on the local climate at ground level on account of thermal discharges of the cooling towers customary today are small, and they do not represent a problem to meteorological environmental protection. This is to be attributed to technical measures such as sufficient height of the cooling towers, preventing the discharge of large drops, enabling the plumes to reach big heights. On the basis of existing knowledge, it can also be said that waste heat discharged via wet cooling towers with cooling capacities up to 3,000 MWe, which are already quite customary these days, do not bring disadvantages for the surrounding area. This also applies to several cooling towers of similar size put together. Small changes in some meteorological elements in the immediate vicinity can be just as little looked upon as hazards to the environment as the low increases in temperature and precipitation in major towns and industrial, densely populated areas, which - true to say - cannot be compared but which have been known for a long time. (orig.)

  15. 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.)

  16. 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)

  17. Advanced wet--dry cooling tower concept performance prediction

    Energy Technology Data Exchange (ETDEWEB)

    Snyder, T.; Bentley, J.; Giebler, M.; Glicksman, L.R.; Rohsenow, W.M.

    1977-01-01

    The purpose of this year's work has been to test and analyze the new dry cooling tower surface previously developed. The model heat transfer test apparatus built last year has been instrumented for temperature, humidity and flow measurement and performance has been measured under a variety of operating conditions. Tower Tests showed approximately 40 to 50% of the total energy transfer as taking place due to evaporation. This can be compared to approximately 80 to 85% for a conventional wet cooling tower. Comparison of the model tower test results with those of a computer simulation has demonstrated the validity of that simulation and its use as a design tool. Computer predictions have been made for a full-size tower system operating at several locations. Experience with this counterflow model tower has suggested that several design problems may be avoided by blowing the cooling air horizontally through the packing section. This crossflow concept was built from the previous counterflow apparatus and included the design and fabrication of new packing plates. Instrumentation and testing of the counterflow model produced data with an average experimental error of 10%. These results were compared to the predictions of a computer model written for the crossflow configuration. In 14 test runs the predicted total heat transfer differed from the measured total heat transfer by no more than 8% with most runs coming well within 5%. With the computer analogy's validity established, it may now be used to help predict the performance of fullscale wet-dry towers.

  18. 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

  19. 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.

  20. 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)

  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. 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.)

  3. Legionella control in cooling towers by electrolytic disinfection

    Energy Technology Data Exchange (ETDEWEB)

    Forstmeier, M.; Wozny, G. [Institut fuer Prozess- and Anlagentechnik, KWT 9, Technical University Berlin, Strasse des 17. Juni 135, 10623 Berlin (Germany); Buss, K.; Toelle, J. [newtec Umwelttechnik GmbH, Skalitzer Strasse 104, 10997 Berlin (Germany)

    2005-07-01

    The cooling towers of any industrial plant pose a large risk due to the existence of hazardous micro-organisms, especially Legionellae. The electrolytic disinfection process has a wide applicability in the process industry. The results of an industrial case study are presented. (Abstract Copyright [2005], Wiley Periodicals, Inc.)

  4. 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.)

  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. 40 CFR 63.1329 - Process contact cooling towers provisions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Process contact cooling towers provisions. 63.1329 Section 63.1329 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards for Hazardous...

  8. Meteorological effects of heat extraction by cooling towers

    International Nuclear Information System (INIS)

    The meteorological effects depend on the strength and spatial distribution of the sources of emission and on the atmospheric conditions at the time. Numerical simulation models are calculated for individual cases. The problems, e.g. for wet cooling towers, are in the quantitative measurement or estimation of the effects. (DG)

  9. Cooling tower and plume modeling for satellite remote sensing applications

    Energy Technology Data Exchange (ETDEWEB)

    Powers, B.J.

    1995-05-01

    It is often useful in nonproliferation studies to be able to remotely estimate the power generated by a power plant. Such information is indirectly available through an examination of the power dissipated by the plant. Power dissipation is generally accomplished either by transferring the excess heat generated into the atmosphere or into bodies of water. It is the former method with which we are exclusively concerned in this report. We discuss in this report the difficulties associated with such a task. In particular, we primarily address the remote detection of the temperature associated with the condensed water plume emitted from the cooling tower. We find that the effective emissivity of the plume is of fundamental importance for this task. Having examined the dependence of the plume emissivity in several IR bands and with varying liquid water content and droplet size distributions, we conclude that the plume emissivity, and consequently the plume brightness temperature, is dependent upon not only the liquid water content and band, but also upon the droplet size distribution. Finally, we discuss models dependent upon a detailed point-by-point description of the hydrodynamics and thermodynamics of the plume dynamics and those based upon spatially integrated models. We describe in detail a new integral model, the LANL Plume Model, which accounts for the evolution of the droplet size distribution. Some typical results obtained from this model are discussed.

  10. 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

  11. Assessing the environmental health relevance of cooling towers--a systematic review of legionellosis outbreaks.

    Science.gov (United States)

    Walser, Sandra M; Gerstner, Doris G; Brenner, Bernhard; Höller, Christiane; Liebl, Bernhard; Herr, Caroline E W

    2014-03-01

    Bioaerosols from cooling towers are often suspected to cause community-acquired legionellosis outbreaks. Although Legionella infections can mostly be assigned to the emission sources, uncertainty exists about the release and distribution into the air, the occurrence of the respirable virulent form and the level of the infective concentration. Our study aimed to evaluate studies on legionellosis outbreaks attributed to cooling towers published within the last 11 years by means of a systematic review of the literature. 19 legionellosis outbreaks were identified affecting 12 countries. Recurring events were observed in Spain and Great Britain. In total, 1609 confirmed cases of legionellosis and a case-fatality rate of approximately 6% were reported. Duration of outbreaks was 65 days on average. For diagnosis the urinary antigen test was mainly used. Age, smoking, male sex and underlying diseases (diabetes, immunodeficiency) could be confirmed as risk factors. Smoking and underlying diseases were the most frequent risk factors associated with legionellosis in 11 and 10 of the 19 studies, respectively. The meteorological conditions varied strongly. Several studies reported a temporal association of outbreaks with inadequate maintenance of the cooling systems. A match of clinical and environmental isolates by serotyping and/or molecular subtyping could be confirmed in 84% of outbreaks. Legionella-contaminated cooling towers as environmental trigger, in particular in the neighbourhood of susceptible individuals, can cause severe health problems and even death. To prevent and control Legionella contamination of cooling towers, maintenance actions should focus on low-emission cleaning procedures of cooling towers combined with control measurements of water and air samples. Procedures allowing rapid detection and risk assessment in the case of outbreaks are essential for adequate public health measures. Systematic registration of cooling towers will facilitate the identification of the source of outbreaks and help to shorten their duration. PMID:24100053

  12. 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)

  13. ESTIMATION OF DOWNWIND VIABLE AIRBORNE MICROBES FROM A WET COOLING TOWER - INCLUDING SETTLING

    Science.gov (United States)

    In recent years, reuse of municipal waste water as the coolant in drift-producing cooling towers at electrical generating plants has become increasingly common. A hueristic model is presented that can be used to estimate the concentrations of viable airborne microbes in the drift...

  14. 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

  15. Recent developments in the design of large cooling towers

    International Nuclear Information System (INIS)

    The growth of power plant units has initiated the development of very large cooling towers. The shell curvature of such towers is comparably small producing an increase of bending effects due to loads with a non-uniform distribution, such as turbulent wind pressures. The validity of the current concept of equivalent static wind loads is inspected. Some deficiencies may occur underrating the actual stresses. A simplified, quasi-static method of calculation is described including dynamic loading data obtained from wind-tunnel tests. (Author)

  16. Cooling tower drift: experiment design for comprehensive case study

    International Nuclear Information System (INIS)

    A drift experiment program to develop a data base which can be used for validation of drift deposition models has been formulated. The first field effort is designed for a suitable mechanical-draft cooling tower to be selected after site visits have been conducted. The discussion here demonstrates the importance of characterizing the droplet size spectrum emitted from the tower and to accurately account for droplet evaporation, because the downwind droplet deposition patterns and near-surface airborne concentrations are extremely sensitive to these parameters

  17. 40 CFR 61.134 - Standard: Naphthalene processing, final coolers, and final-cooler cooling towers.

    Science.gov (United States)

    2010-07-01

    ... coolers, and final-cooler cooling towers. 61.134 Section 61.134 Protection of Environment ENVIRONMENTAL... Standard: Naphthalene processing, final coolers, and final-cooler cooling towers. (a) No (“zero”) emissions are allowed from naphthalene processing, final coolers and final-cooler cooling towers at coke...

  18. 75 FR 16732 - Action Affecting Export Privileges; Aqua-Loop Cooling Towers, Co.

    Science.gov (United States)

    2010-04-02

    ... of Industry and Security Action Affecting Export Privileges; Aqua-Loop Cooling Towers, Co. In the Matter of: 09-BIS-006, Aqua-Loop Cooling Towers, Co., P.O. Box 966, Folsom, CA 95763, and 116 Hopper Lane, Folsom, CA 95630, Respondent. Order Relating to Aqua-Loop Cooling Towers, Co. The Bureau of Industry...

  19. Geodesy work in the construction of cooling towers of the Temelin nuclear power plant

    International Nuclear Information System (INIS)

    The specifications are described of the cooling tower foundations, the bottom part of the flue chimney and of the cooling tower casing. In view of the cooling tower configuration, the ground control points inside the tower were selected in the pit bottom and the layout and check were performed of the inner tower wall. The methodology of measuring the basic layout network, and of laying out up to the fiftieth (ca. 80 m) and from the 70th (106 m) strip is described. The measurement results are computer-processed. The accuracy is assessed of the cooling tower construction in the Temelin nuclear power plant. (E.J.). 1 fig., 5 refs

  20. 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.

  1. Magnetic fluid conditioning system allows 3000 ppm hardness without cooling tower scale buildup

    International Nuclear Information System (INIS)

    Big Three Industries, a manufacturer of compressed and liquefied atmospheric gases, operates a large production complex in Bayport, TX which recirculates 100,000 gpm cooling water. Due to regulatory agency guidelines, high costs, and limited effectiveness of conventional chemical treatment methods, Big Three was in need of a treatment method to prevent corrosion and scaling in recirculating water cooling systems. In December 1983 a magnetic fluid conditioner (MFC) was installed in the pump discharge piping of one cooling tower at Bayport. The patented MFC is an 18'' long spool pipe fitted with uranium-based alloy magnets. The MFC has no moving parts and requires no chemicals, external power source, or maintenance. The MFC is designed so that the fluid is accelerated through a magnetic field. The high velocity of the fluid causes nucleation of the salts in the fluid. The salts are separated from the water by precipitation. During eighteen months of using the MFC, the cooling tower has concentrated in excess of 50 cycles. Conductivity is in excess of 10,000 micromhos, and total hardness (CaCO3) is above 4000 ppm with pH stabilized between 8 and 9. However, inspections have revealed clean surfaces. The cleaner metal surfaces within the cooling water system provide better heat transfer which has resulted in reduction of tower blowdown, makeup water requirements, and pumping costs. Associated savings will enable the MFC to achieve payback in two and a half years

  2. 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

  3. 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.

  4. Evaluation of plume potential and plume abatement of evaporative cooling towers in a subtropical region

    International Nuclear Information System (INIS)

    Hong Kong is a typical subtropical region with frequently high humidity in late spring and summer seasons. Plume from evaporative cooling towers, which service air-conditioning systems of civil buildings, has aroused public concerns since 2000 when the fresh water evaporative cooling towers were allowed to be used for high energy efficiency and environmental issues. This paper presents the evaluation of the plume potential and its effect on the sizing of the plume abatement system in a large commercial office building in Hong Kong for practical application. This evaluation was conducted based on a dynamic simulation platform using the typical meteorological year of Hong Kong since the occurrence of the plume heavily depends on the state conditions of the exhaust air from cooling towers and the ambient air, while the state condition of the exhaust air is determined by the total building cooling load and the control strategies of cooling towers employed mainly for improving energy efficiency. The results show that the control strategies have a significant effect on the plume potential and further affect the system design and sizing of the plume abatement system

  5. Prevalence of Legionella strains in cooling towers and legionellosis cases in New Zealand.

    Science.gov (United States)

    Lau, Robert; Maqsood, Saadia; Harte, David; Caughley, Brian; Deacon, Rob

    2013-01-01

    Over 3,900 water samples from 688 cooling towers were tested for Legionella in 2008 in New Zealand. Of 80 (2.05% isolation rate) Legionella isolates, 10 (12.5%) were L. pneumophila serogroup 1; 10 (12.5%) were L. anisa; nine (11.2%) were L. pneumophila serogroup 8; and one (1.2%) was L. longbeachae serogroup 2. Forty-one (51.2%) Legionella isolates were L. pneumophila serogroups. Over 3,990 water samples from 606 cooling towers were tested for Legionella in 2009 in New Zealand. Of 51 (1.28% isolation rate) Legionella isolates, 18 (35.3%) were L. pneumophila serogroup 1, and 39 (76.4%) were other L. pneumophila serogroups. L. pneumophila serogroups were significantly associated with legionellosis cases in 2008 and 2009. L. longbeachae serogroups were equally significantly associated with legionellosis cases. This significant association of L. longbeachae with legionellosis particularly of L. longbeachae serogroup 1 is unique in that part of the world. The authors' study also showed that the aqueous environment of the cooling tower is not a natural habitat for pathogenic L. longbeachae. Regular monitoring and maintenance of cooling towers have prevented outbreaks of legionellosis. PMID:23397654

  6. Numerical modeling of cooling tower plumes: comparison with experiments

    International Nuclear Information System (INIS)

    This chapter compares mathematical models designed to study the impact of cooling tower plumes from a nuclear power plant in France. The 3 models are an integral model for a statistical evaluation of plume characteristics and their cumulative effect (reduction of insolation); a spectral microphysical model, to study the interaction processes between a natural cloud and the plume; and a 3D plume model, involving both dynamics, microphysics and their coupling, to investigate the problems of plumes development, especially in convective situations (cumuli formation). Experimental data were obtained near the BUGEY nuclear power plant (two units of 900 MWe, two natural draft cooling towers per unit). The three models currently used are compared to the experimental data. Includes 3 tables and 3 drawings

  7. Legionella control in power station cooling towers using oxidising biocides

    Energy Technology Data Exchange (ETDEWEB)

    Sailer, Christian; Rawlinson, Julia; Killeen, Paul [Ecolab PTY LTD, Ascot, WA (Australia)

    2009-02-15

    Power stations have used oxidising biocides such as chlorine or bromine for many years to control microbial growth in their cooling towers. In this paper Ecolab trademark looks at the direct effect halogen concentration has on Legionella populations in order to determine the most effective halogenation rate required to ensure that the site key performance indicator (KPI) of < 100 colony-forming units (cfu) per mL can be maintained. (orig.)

  8. 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

  9. 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.

  10. 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.

  11. 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.

  12. 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%.

  13. 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)

  14. A high vibration analysis for a cooling fan of the secondary cooling tower in HANARO

    International Nuclear Information System (INIS)

    HANARO, an open-tank-in-pool type research reactor of 30 MWth power in Korea, which is different from a power plant reactor, exhausts a fission heat generated from the reactor core into the atmosphere through a secondary cooling tower instead of an electric power production from the heat. During every one month inspection of the cooling tower, a No. 4 cooling fan gear reducer of the cooling tower recoded a high unstable vibration above the limit. To find the reason, a frequency analysis was conducted. It was conformed through the results of the frequency analysis that the frequency of the high vibration was 354 HZ which was calculated two times rotation of the pinion gear of the gear reducer. There was a broken of the gear surface of the pinion gear transferred the rotation power. After the repair of the pinion gear, the reducer was operated normally.

  15. 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

  16. 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.

  17. 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

  18. Effect mechanism of air deflectors on the cooling performance of dry cooling tower with vertical delta radiators under crosswind

    International Nuclear Information System (INIS)

    Highlights: • A 3D numerical model was set for NDDCTV to study the effect of air deflectors. • The air deflectors improve the tower performance by 1.375 °C at uc = 6 m/s for a case. • The air deflectors reduce the air inflow deviation angle θd at most delta entries. • The reduced θd can improve the cooling performance of former deteriorated columns. • Both the radial inflow air velocity and θd impact the cooling performance of delta. - Abstract: To study the effect mechanism of air deflectors on dry cooling tower, a three dimensional numerical model was established, with full consideration of the delta structure. The accuracy and credibility of dry cooling tower numerical model were validated. By numerical model, the average air static pressure and the average radial inflow air velocity were computed and analyzed at delta air entry, sector air entry and exit faces. By the air inflow deviation angle θd, the effect of air deflectors on the aerodynamic field around tower was analyzed. The water exit temperatures of θ−1 columns, θ+2 columns and cooling sectors were also presented to clarify the effect of air deflectors. It was found that the air deflectors improved the aerodynamic field around cooling columns. The reduced air inflow deviation degree at delta entry improved the cooling performance of deteriorated columns. Referring to the radial inflow air velocity ura and the air inflow deviation degree at delta entry, the effect mechanism of air deflectors are clarified under crosswind

  19. 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.

  20. 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.

  1. 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

  2. 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

  3. 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.

  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. 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.)

  6. 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)

  7. Physical quantities related to measurement campaigns for cooling towers

    International Nuclear Information System (INIS)

    The nomenclature in reports on the measurement campaigns for cooling towers will be adapted as far as possible to the already existing VDI report on this subject. On the other hand, the appropriate standards will also be accounted for. In order to facilitate a decision in individual cases in a first table the meteorologically or generally interesting quantities of the VDI reports are compared with the German, international, and WMO standards and - if necessary - also commented. A second table contains the air humidity parameters standardized by WMO including brief definitions. (orig/HP)

  8. 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

  9. Wind induced vibrations of reinforced concrete cooling tower shells

    International Nuclear Information System (INIS)

    Natural draught cooling towers are shell structures subjected to random vibrations due wind turbulence. The random response may be analyzed using a spectral approach nad assuming a linear elastic behaviour of the structure. Coupling between the different modes of vibration has to be taken into account. The excitation is given in terms of spectra and cross-spectra of the pressure fluctuations on the shell surface which are related to the spectrum of wind turbulence. The results show in particular that the resonant part of the response remains small even under unfavourable conditions. (Author)

  10. 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

  11. 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

  12. The Merkel equation revisited: A novel method to compute the packed height of a cooling tower

    International Nuclear Information System (INIS)

    Highlights: ? A relationship between packed height and excess air flow rate is derived. ? The relationship is independent of tower diameter and water flow rate. ? It is well approximated by a power law curve for industrially relevant cases. ? An algorithm to compute the thermodynamic minimum air flow rate is detailed. ? Computation of the packed height is simplified especially for design-optimization. - Abstract: In this work, a new methodology of analysis and computation is presented which simplifies calculation of the packed height in a counter current cooling tower, especially for design and cost optimization studies. An algorithm is presented with an implementation in MATLAB to compute the thermodynamic minimum air flow rate for the desired cooling. Combining the Merkel equation and a standard empirical mass transfer correlation, the packed height is shown to be independent of the water flow rate and tower diameter, and dependent only on the excess air flow. The relationship is unique for a given cooling range of water and inlet air wet bulb temperature. A simple power law regression is used to approximate this relationship and results are presented for Vertical Corrugated Packing.

  13. 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

  14. Operating experience with cooling towers in French nuclear power stations: hydrobiology - aquatic chemistry

    International Nuclear Information System (INIS)

    This paper summarizes the difficulties encountered because of biological contaminants polluting the cooling towers of nuclear power stations. Then one describes the measures planned to reduce these phenomena

  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. 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.)

  17. 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.

  18. 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.)

  19. 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

  20. 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

  1. Demineralised water cooling in the LHC accelerator

    CERN Document Server

    Peón-Hernández, G

    2002-01-01

    In spite of the LHC accelerator being a cryogenic machine, it remains nevertheless a not negligible heat load to be removed by conventional water-cooling. About 24MW will be taken away by demineralised water cooled directly by primary water from the LHC cooling towers placed at the even points. This paper describes the demineralised water network in the LHC tunnel including pipe diameters, lengths, water speed, estimated friction factor, head losses and available supply and return pressures for each point. It lists all water cooled equipment, highlights the water cooled cables as the most demanding equipment followed by the radio frequency racks and cavities, and by the power converters. Their main cooling requirements and their positions in the tunnel are also presented.

  2. 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

  3. A simulation-based method to analyse the behaviour of rc cooling towers shells

    International Nuclear Information System (INIS)

    This paper deals with numerical simulations undertaken for the service life and maintenance management of EDF cooling towers. Following a presentation of the industrial context and of the numeric tools dedicated to RC structure ageing, two finite element models are presented. The first one aims at simulating the collapse of a tower fallen down in 1979, the second one is devoted to the assessment of damages undergone by cooling towers during the 1999 tempest in France. (authors)

  4. 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.

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

    Science.gov (United States)

    Li, Lijie; Qin, Tian; Li, Yun; Zhou, Haijian; Song, Hongmei; Ren, Hongyu; Li, Liping; Li, Yongguang; Zhao, Dong

    2015-10-01

    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. PMID:26473896

  6. PERFORMANCE EVALUATION OF THE BRAINTREE ELECTRIC LIGHT DEPARTMENT DRY COOLING TOWER

    Science.gov (United States)

    The report gives results of a 5-year evaluation of the performance of a dry cooling tower for the 20-MW steam-electric generation portion of an 85-MW combined-cycle power plant. Objectives of the study were to: demonstrate dry cooling tower technology at a Massachusetts seacoast ...

  7. 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

  8. Fog and drift deposition from evaporative cooling towers

    International Nuclear Information System (INIS)

    Methods of determining fog and drift deposition due to emissions from evaporative cooling towers are reviewed and formulas suggested that can be used as a basis for calculations. The Gaussian plume formula is recommended for calculating fog concentrations from which visibility can be estimated. For drift droplets with diameters greater than 200 ?m, deposition is calculated by ballistics methods, knowing the environmental wind speed and relative humidity and the vertical velocity of the plume and the droplet. Evaporation of the droplets is accounted for. Drift droplets with diameters less than 200 ?m are assumed to be dispersed according to the Gaussian plume formula, with the plume tilted downward to account for the settling speed of the droplet

  9. 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

  10. 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

  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. Successful implementation of ageing management exemplified at the cooling tower of Emsland nuclear power plant

    International Nuclear Information System (INIS)

    The present paper describes the successful implementation of the restoration of water-distribution channels at the cooling tower of the Emsland nuclear power plant under the aspect of ageing management. The main challenge of aging management is the determination of potential aging mechanism and to avoid systematically and effectively their damaging influences. In the course of the annual site inspections abnormalities at the lower side of the water-distribution channels of the cooling tower were detected, analysed, and repaired. The extraordinary high chlorine equivalent of the cooling water was identified as main reason of the damages located. Due to extensive infiltration into the concrete structure, chloride-induced corrosion generates a volume expansion of the reinforcement and thereby to a blast off of the concrete covering. According to the restoration concept, the damaged concrete was removed by maximum pressure water jet blasting; where necessary the reinforcement was retrofitted and a layered concrete substitution was applied by synthetic cement mortar. The realised procedures conserve the load bearing reinforcement only for a certain period, because the permanent chloride infiltration could not be stopped. Therefore, the structure has to be monitored permanently. (orig.)

  13. 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

  14. 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.

  15. 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.

  16. COMPARISON OF MODEL PREDICTIONS AND CONSUMPTIVE WATER USE OF CLOSED CYCLE COOLING SYSTEMS

    Science.gov (United States)

    The report gives results of a comparison of field-data-derived water evaporation rates with predictive model values for cooling towers and cooling ponds at steam-electric generating plants. The Leung Moore cooling tower model and five cooling pond models (Harbeck and Marciano; Ha...

  17. Cooling towers: design and performance (citations from the Engineering Index Data Base). Report for 1970-August 1978

    International Nuclear Information System (INIS)

    Abstracts from worldwide research on design and performance of mechanical draft and natural draft wet, dry, and dry-wet combination cooling towers are discussed. Citations cover studies on size reduction, corrosion protection, and economic optimization of cooling towers primarily used with nuclear power plants and fossil fuel power plants. A few abstracts pertain to cooling towers used in wastewater treatment

  18. 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.)

  19. 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.

  20. 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.

  1. 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...

  2. POWER PLANT COOLING SYSTEM WATER CONSUMPTION AND NONWATER IMPACT REPORTS

    Science.gov (United States)

    This study dealt with water evaporation and consumption of power plant cooling systems and evaluated six simple generic evaporation prediction models, one for cooling towers and five for cooling ponds/lakes using field data provided by twelve utilities. Also evaluated in the stud...

  3. 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)

  4. 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.

  5. Organohalogens in chlorinated cooling waters discharged from nuclear power stations

    International Nuclear Information System (INIS)

    For the power plant discharges studied to date, measured concentrations of trihalomethanes are lower than might be expected, particularly in cooling tower water, which can lose THMs to the atmosphere. In the cooling towers, where chlorine was added in higher concentrations and for longer residence times, halogenated phenols can contribute significantly to the total organic halogen content of the discharge. The way in which cooling towers are operated may also influence the production of halogenated phenols because they concentrate the incoming water by a factor of 4 or 5. In addition, the phenols, which act as a substrate for the halogenating agent, are also probably concentrated by the cooling tower operation and may be prevented from being biodegraded by addition of the same biocide that produces the halogenated phenols. 8 references, 4 tables

  6. 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

  7. 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)

  8. Research on the Flow-Head Characteristics of the Turbine Driving Fan in Cooling tower

    Directory of Open Access Journals (Sweden)

    Li Yanpin

    2012-11-01

    Full Text Available The flow-head characteristics of the special turbine in cooling tower are very different from the general power turbines’. This study has analyzed the former theoretically and proposed the theoretical formula of the head-flow. At the same time, the paper has studied the characteristics of the flow-head using the CFD method. The tests results have proved the principle of the flow-head of the turbine in cooling tower.

  9. Comparison between wind and solar effects on static stresses in natural draught cooling tower

    International Nuclear Information System (INIS)

    A thermal simulation of a cooling tower shell under sunshine was carried out. The associated constraints are virtually isotropic and change signs from one side of the shell to the other. The comparison with a schematic study of wind plus inherent weight shows that the thermal constraints are in the order of one third of the maximum constraints. The results presented correspond to the structure of a proposed 1300 MW type cooling tower 165 metres high

  10. Demolition of Cooling Towers from the World's First Commercial Reactors - the Nuclear Factor

    International Nuclear Information System (INIS)

    The demolition of hyperbolic cooling towers would be a relatively routine demolition project because the method of demolition has been proven straightforward and repeatable with the successful demolition of over 200 similar structures in the last 30 years. This paper will detail the unique aspects of the planning and execution of the cooling tower demolition project due to its location on a nuclear site and proximity to active nuclear operations. (authors)

  11. 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

  12. Effect of output heat from WWER-1000 type nuclear power plants on evaporation in cooling towers

    International Nuclear Information System (INIS)

    The paper deals with problems of the large amounts of waste heat and related problems of large steam discharges from cooling towers which will arise for the WWER-1000 NPP units to be erected in the CSSR. As all these units will be operated in a cogeneration mode, a study has been made to calculate evaporation from a cooling tower as a function of atmospheric conditions of the environment and of the heat power bleeded off the unit. (author)

  13. Loy Yang power - cooling tower chemical dosing implementation: practical findings

    Energy Technology Data Exchange (ETDEWEB)

    Lindsay, J. [BetzDearborn, Latrobe Valley (Australia)

    2004-06-01

    From early 2001, GE Betz were given the opportunity to treat the Loy Yang power station cooling water systems to control microbiological activity and corrosion of the copper-based metallurgy in those systems. After commencing with continuous dosing of sodium hypochlorite as the biocide and the traditional tolyltriazole (TTA) as the copper corrosion inhibitor, the treatment program was optimised over the next year of operation. Sodium hypochlorite efficiency was determined by monitoring of both Legionella and total bacteria to determine the effectiveness of the biocide program and by using oxidation reducing potential to measure on-line the activity of the biocide. Copper corrosion inhibitor efficiency was determined using the on-line linear polarisation resistance technique (corrator), corrosion coupons and by measuring copper concentrations in the recirculating cooling water. (orig.)

  14. 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.)

  15. Controlling the shape of cooling towers in the construction of the Temelin nuclear power plant

    International Nuclear Information System (INIS)

    Eight reinforced concrete shell-type cooling towers with natural draught in the shape of a hyperboloid of revolution were designed for the Temelin nuclear power plant. The tower structure is very sensitive to shape deviations. Calculations confirmed that, e.g., a small alteration in the tower radius from the ideal shape significantly changes the state of stress. A new procedure was designed for measuring the cooling tower shape using electronic equipment from Wild company. Briefly discussed are preliminary results of the measurement of deviations of the top edges of shuttering plates prior to and after concreting. The maximum deviation was 46 mm. It is shown that using the new method, it will be possible to build a tower with tolerances satisfying not only the requirements of the project design but also much more stringent requirements of IASS recommendations. (Z.M.). 5 figs., 4 refs

  16. Substitution of cooling tower components in the nuclear power plant Goesgen-Daeniken AG

    International Nuclear Information System (INIS)

    At the nuclear power plant Goesgen-Daeniken AG (Daeniken, Switzerland), the cooling tower installations of asbestos cement to have been replaced by plastics. The resulting continuous decrease in the cooling capacity is based on a weakly dimensioned wall thickness of the film installations and on a deposition of suspended matter. The deposition of suspended matter additionally was favoured by biofilms on the film surface. Four measures are presented for the remediation of this problematic situation. With this, the contamination of the film installations are minimized. Deformations of foil packets can be avoided. The cooling capacity of the cooling tower significantly has been improved.

  17. 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.

  18. 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.

  19. 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

  20. 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)

  1. A heat recovery system for air conditioning which allows disposal of wet cooling towers.

    Science.gov (United States)

    McCullough, J

    1988-04-01

    The combined run-around coil heat recovery and cooling plant has been in full operation for about four months at the time of writing and appears to be performing as predicted. The predicted energy saving was 19,000 GJ/year and the actual is around 18,000 GJ/year. It provides a general limited cooling facility of 6 degrees K where previously cooling existed for operating theatres only. The capital cost of the total project was 390,000 pounds and disregarding fuel price fluctuations the heat recovery scheme should pay for itself in about seven years. In addition to the heat recovery and cooling provisions offered the scheme also enabled correction of a frost protection problem plus disposal of an existing wet cooling tower and hence should reduce the risk of Legionnaires Disease. Had these two projects been implemented separately the cost would have been 80,000 pounds but without heat recovery. The advantages of the scheme may be summarised as follows. Energy Cost Savings Frost Protection Elimination of Wet Cooling Tower Cooling Facility It is believed that a scheme as described in this paper would be of benefit to other existing hospitals and should be considered at the design stage of future new hospitals. At IRH it was possible to dispense completely with a wet cooling tower; for other schemes this may also be possible or at least the size and capacity of cooling towers could be reduced. PMID:10293020

  2. Assessment of cooling tower (ultimate heat sink) performance in the Byron individual plant examination

    International Nuclear Information System (INIS)

    A time-dependent model of the Byron Nuclear Generation Station safety-related cooling towers has been developed for use with the Byron PRA (IPE). The model can either be run in a stand-alone program with externally supplied heat loads, or can be directly coupled into MAAP (Modular Accident Analysis Program). The primary feature of the model is a careful tracking of the basin temperature through the progression of different severe accidents. Heat removal rates from containment, both from containment fan-coolers and the residual heat removal system, are determined by the feed-back of this time-varying return temperature. Also, the inventory of the basin is tracked in time, and this is controlled by make-up, evaporative losses due to the heat load supplied to the towers, and the possibility of unsecured blowdown. The model has been used to determine the overall capabilities and vulnerabilities of the Byron Ultimate Heat Sink (UHS). It was determined that the UHS is very reliable with respect to maintaining acceptably low basin temperatures, requiring only at most two of eight operating cooling tower fans. Further, when the two units have their Essential Service Water (ESW) systems cross-tied, one of four ESW operating pumps is sufficient to handle the loads from the accident unit with the other unit proceeding to an orderly shutdown. The major vulnerability of the Byron UHS is shown to be the ability to maintain inventory, although the time-scales for basin dry-out are relatively long, being eight to twenty-one hours, depending upon when blowdown is secured. (author)

  3. 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.

  4. 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.)

  5. 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

  6. 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...

  7. 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.)

  8. 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.

  9. 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

  10. Influence of cooling towers and mountain ridges of plume dispersions from nuclear power plants

    International Nuclear Information System (INIS)

    Calculation of atmospheric dispersion of stack-released air pollutants by the Gaussian model is not applicable if the plume is affected by high buildings, especially cooling towers, or mountain ridges. Since for such distortions of plume dispersion calculation models for use in practice are lacking, experiments in two 'atmospheric' wind tunnels were done to investigate the influence of cooling towers (out of action or in operation respectively) and two-dimensional ridges on plume dispersion. Investigations were done for stacks in flat terrain, for one or two nearby cooling towers and for ridges of different shapes upwind and downwind from the stack. The concentration of stack-released tracer-effluents was measured along, across and vertical to the atmospheric flow direction. Measurements show a variation of horizontal and vertical plume spreading and height of plume center line compared with the undisturbed flow in relation to the position upwind or downwind, the height difference and distance between stack and cooling tower or ridge and the fact, whether the cooling tower is in operation or not. Guidance is given how to modify the parameters of the Gaussian plume model describing horizontal and vertical plume spreading and effective release height to take into account ground level concentrations for distorted plumes as measured in the wind tunnel in a good approximation. (orig.)

  11. 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.

  12. Wind tunnel experimental study on effect of inland nuclear power plant cooling tower on air flow and dispersion of pollutant

    International Nuclear Information System (INIS)

    A wind tunnel experiment for the effect of the cooling tower at Taohuajiang nuclear power plant on air flow and dispersion of pollutant was introduced in paper. Measurements of air mean flow and turbulence structure in different directions of cooling tower and other buildings were made by using an X-array hot wire probe. The effects of the cooling tower and its drift on dispersion of pollutant from the stack were investigated through tracer experiments. The results show that the effect of cooling tower on flow and dispersion obviously depends on the relative position of stack to cooling towers, especially significant for the cooling tower parallel to stack along wind direction. The variation law of normalized maximum velocity deficit and perturbations in longitudinal turbulent intensity in cooling tower wake was highly in accordance with the result of isolated mountain measured by Arya and Gadiyaram. Dispersion of pollutant in near field is significantly enhanced and plume trajectory is changed due to the cooling towers and its drift. Meanwhile, the effect of cooling tower on dispersion of pollutant depends on the height of release. (authors)

  13. 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...

  14. Isolation of Legionella pneumophila from cooling towers, public baths, hospitals, and fountains in Seoul, Korea, from 2010 to 2012.

    Science.gov (United States)

    Kim, Changkyu; Jeon, Sujin; Jung, Jihun; Oh, Younghee; Kim, Yeonsun; Lee, Jaein; Choi, Sungmin; Chae, Youngzoo; Lee, Young-Ki

    2015-01-01

    Legionnaire's disease is associated with a high mortality rate. The authors collected 3,495 water samples in Seoul, Korea, between 2010 and 2012 from public facilities (cooling towers, public baths, hospitals, and decorative fountains), which are considered the major habitats of Legionella pneumophila. In all, 527 (15.1%) isolates of L. pneumophila were obtained by microbial culture and polymerase chain reaction. Serological diagnosis and pulsed-field gel electrophoresis (PFGE) analysis were performed for the samples. The authors categorized the samples into four groups (A-D) on the basis of PFGE results. The analysis revealed that cooling towers containing the most samples with L. pneumophila serogroup 1 constituted the highest proportion of isolate. Samples from public facilities and serogroups could be distinctively classified by PFGE patterns. Thus, it is expected that source-specific features revealed through PFGE and serological analyses could serve as the basis for effectively coping with future outbreaks of L. pneumophila. PMID:25619037

  15. 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).

  16. 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.

  17. 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.)

  18. 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)

  19. 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

  20. 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)

  1. 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.

  2. 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

  3. 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

  4. Prevalence and concentration of non-tuberculous mycobacteria in cooling towers by means of quantitative PCR: a prospective study.

    Science.gov (United States)

    Adrados, Bárbara; Julián, Esther; Codony, Francesc; Torrents, Eduard; Luquin, Marina; Morató, Jordi

    2011-01-01

    There is an increasing level of interest in non-tuberculous mycobacteria (NTM) due to the increasing reported rates of diseases caused by them. Although it is well known that NTM are widely distributed in the environment it is necessary to identify its reservoirs to prevent possible infections. In this study, we aimed to investigate the occurrence and levels of NTM in cooling towers to provide evidences for considering these settings as possible sources of respiratory infections. In the current study, we detected and quantified the presence of NTM by means of a rapid method in water samples taken from 53 cooling towers of an urban area (Barcelona, Spain). A genus-specific quantitative PCR (Q-PCR) assay with a quantification limit (QL) of 500 cells l(-1) was used. 56% (30) of samples were positive with a concentration range from 4.6 × 10(3) to 1.79 × 10(6) cells l(-1). In some cases (9/30), samples were positive but with levels below the QL. The colonization rate confirmed that cooling towers could be considered as a potential reservoir for NTM. This study also evaluated Q-PCR as a useful method to detect and quantify NTM in samples coming from environmental sources. PMID:20640853

  5. 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

  6. Improvement of mathematical models for plume rise and drift deposition from cooling towers

    International Nuclear Information System (INIS)

    New models for plume rise and salt-drift deposition from cooling towers and presented. For plume rise, assumptions are made which help resolve the usual difficulty of correclty predicting both plume trajectory and dilution. The multiple-tower plume merging method accounts for different rates of entrainment depending on the orientation of the merging plumes with the wind direction. Model calibration and verification have been made with field and laboratory data from natural- and mechanical-draft cooling towers. For salt-drift deposition modeling, new droplet breakaway and droplet evaporation formulations are developed. The drop evaporation treatment accounts for the usually important effects of droplet salt-concentration gradients. The drift model has been validated with field data taken at the Chalk Point site. (Auth.)

  7. Thermal Characteristics of Heating Towers

    Science.gov (United States)

    Fujita, Toshihiko; Kametani, Shigeki

    Thermal characteristics of heating towers for air-source heat pumps are studied in terms of the overall enthalpy-transfer coefficient. Ka. First. the method of counter-flow calculation is presented taking physical properties of ethylene glycol solutions into account. Next, both cooling-tower and heating-tower experiments are carried out in a small, induced-draft. counterflow tower packed with tubes of a staggerd arrangement. using water and commercial ethylene glycol solutions. The coefficient Ka measured in the heating-tower experiment shows a trend similar to that in the cooling-tower experiment. So. the data on cooling towers will be helpful to the thermal design of heating towers.

  8. 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.

  9. TESTING AND ANALYSIS OF A WET-DRY CROSSFLOW COOLING TOWER, VOLUME II: APPENDICES

    Science.gov (United States)

    The report discusses the test program and performance analysis of a single-cell mechanical-draft wet/dry cooling tower in Cliffside, NC. Objectives of the program were to obtain performance data and results on mass transfer, heat transfer, fluid flow, plume formation, and acousti...

  10. In Situ g-PHA Measurements of the 285-3H Cooling Tower Components

    International Nuclear Information System (INIS)

    The Analytical Development Section of Savannah River Technology Center was requested by the Facility Disposition Division to conduct in-situ gamma-ray pulse height analysis measurements to provide input toward the decision to unconditionally release the 285-3H cooling tower

  11. SIMULATION OF COOLING TOWER AND INFLUENCE OF AERODYNAMIC ELEMENTS ON ITS WORK UNDER CONDITIONS OF WIND

    Directory of Open Access Journals (Sweden)

    K. V. Dobrego

    2015-02-01

    Full Text Available Modern Cooling Towers (CT may utilize different aerodynamic elements (deflectors, windbreak walls etc. aimed to improvement of its heat performance especially at the windy conditions. In this paper the effect of flow rotation in overshower zone of CT and windbreak walls on a capacity of tower evaporating unit in the windy condition is studied numerically. Geometry of the model corresponds to real Woo-Jin Power station, China. Analogy of heat and mass transfer was used that allowed to consider aerodynamic of one-dimension flow and carried out detailed 3D calculations applying modern PC. Heat transfer coefficient of irrigator and its hydrodynamic resistance were established according to experimental data on total air rate in cooling tower. Numerical model is tested and verified with experimental data.Nonlinear dependence of CT thermal performance on wind velocity is demonstrated with the minimum (critical wind velocity at ucr ~ 8 m/s for simulated system. Application of windbreak walls does not change the value of the critical wind velocity, but may improves performance of cooling unit at moderate and strong wind conditions. Simultaneous usage of windbreak walls and overshower deflectors may increase efficiency up to 20–30 % for the deflectors angle a = 60o. Simulation let one analyze aerodynamic patterns, induced inside cooling tower and homogeneity of velocities’ field in irrigator’s area.Presented results may be helpful for the CT aerodynamic design optimization, particularly, for perspective hybrid type CTs.

  12. Modeling and characteristics analysis of hybrid cooling-tower-solar-chimney system

    International Nuclear Information System (INIS)

    Highlights: • A 3-D model for hybrid cooling-tower-solar-chimney system is developed. • The inclusion of heat exchangers into solar chimney boosts the power output. • The huge jump in power output is at the expense of heat dissipation capacity. • The heat exchanger as second heat source has greater impact on system performance. - Abstract: The hybrid cooling-tower-solar-chimney system (HCTSC), combining solar chimney with natural draft dry cooling tower, generates electricity and dissipates waste heat for the coupled geothermal power plant simultaneously. Based on a developed 3-D model, performance comparisons between the HCTSC system, solar chimney and natural draft dry cooling tower were performed in terms of power output of turbine and heat dissipation capacity. Results show that compared to the traditional solar chimney with similar geometric dimensions, HCTSC system can achieve over 20 times increase in the power output of turbine. However, this huge jump in power output is at the expense of heat dissipation capacity, which may lead to the malfunction of the coupled thermal power plant. By increasing the heat transfer area of the heat exchanger, the HCTSC system can manage to recover its heat dissipation capacity

  13. 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)

  14. Wind tunnel experiments on cooling tower plumes. Pt. 2

    International Nuclear Information System (INIS)

    The basic characteristics of plumes issuing into a boundary layer type of cross flow are reported. The flow can be considered as an interaction between two vorticity fields with different length scales and turbulence intensities. The large eddies of the oncoming boundary layer are responsible for the observed sudden changes in the plume direction. The type of structures emanating the tower depends on the instantaneous velocity ratio. Mean velocities and normal velocity gradients are smaller than in the case of uniform cross-flow (Andreopoulos, 1986) and therefore the measured turbulence intensities were lower too. The cross-stream turbulence brings high momentum fluid into the wake region and the velocity defect decays very rapidly. Dilution of the plumes takes place faster in the presence of external turbulence than in the case with uniform cross-flow. The spreading rate is increased dramatically by the external turbulence which causes different effects on the hydrodynamic and thermal fields. (orig.)

  15. 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.)

  16. 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

  17. Model calculations of the space and time distribution of cooling tower clouds on the basis of aerological data delivered by the German Weather Service (Deutscher Wetterdienst)

    International Nuclear Information System (INIS)

    Based on a large amount of aerological data, the simulation model for cooling tower cloud propagation Smoka has been used to allow for a statistical evaluation of the influence of cooling towers. In addition to local differences, the annual and daily variations in the formation of clouds can be obtained together with the dependence on the cloud coverage conditions and the cooling tower characteristics. With these model calculations of the cooling tower clouds, the respective decrease in sunshine duration can be evaluated. (orig.)

  18. Some observations on modelling the mechanical-draft cooling tower plume at plant Gaston

    Science.gov (United States)

    Slawson, P. R.

    Observations on the far-field time mean condensed plumes from the twin mechanical-draft cooling towers at the Gaston Steam Plant, Willsonville, Alabama taken during February 1975 and January-February 1976 are compared with a one-dimensional integral model for moist plume behaviour. Empirical modifications are required to account for the near-field effects of downwash, source geometry, wind direction relative to tower alignment and the far-field effects of vertical and wind direction shear on plume behaviour. Details on source and ambient parameters are given.

  19. 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.)

  20. Light water cooled reactor

    International Nuclear Information System (INIS)

    In an emergency condensator for a light water cooled type reactor, a heat transfer pipe is submerged in a pool of an emergency condensator system, a water condensation chamber is disposed at the outside of the pool by way of concrete walls, and a steam chamber is disposed in the water condensation chamber. The emergency condensator can be reduced in the size and maintenance/inspection for the water condensation chamber and the heat transfer pipe can be conducted without withdrawing pool water. Further, the heat transfer pipe is formed as a horizontally extended U-shaped pipe, both legs of the U-shaped pipe are inclined in order not to stagnate condensates in the heat transfer pipe, and a great number of holes are perforated to a support shell to smooth the flow of coolants on the side of the body, to improve heat exchange performance of the heat transfer pipe. Further, the heat transfer pipe is supported by a buffle, the buffle is secured to the support shell and the support shell is secured to a support saddle, to provide a strength sufficient to withstand the own weight of the heat transfer pipe and earthquakes. A bent tube is disposed to the water condensation chamber to discharge incondensible gases stagnated in the water condensation chamber by leading them to the coolant pool in the wet well. (N.H.)

  1. 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.)

  2. 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)

  3. 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.)

  4. 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)

  5. 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)

  6. The maintenance and Repair of the Secondary Cooling Tower Operation of the HANARO for Ten years and Vibration Analysis of the Cooling Fan

    International Nuclear Information System (INIS)

    The HANARO is a multi-purpose reactor, 30MWth open-tank-in-pool type. Since the HANAO started the critical operation in 1995, it has been normally in operation at present. Heat generated by nuclear fission during the operation of the HANARO is absorbed by the primary coolant and is transmitted to the secondary coolant. The secondary coolant which passes through the cooling tower by means of the circulating pump is refrigerated by the heat exchanger with atmospheric air when the cooling fan operates. In order to operate the HANARO safely, it is essential for the cooling tower to have the sufficient cooling ability. Therefore, the records about maintenance and repair of the cooling tower were analyzed in detail to prevent the failure of the cooling tower in advance. Finally, the cooling tower of the HANARO has a good condition at present and the analysis in maintenance and repair of the cooling tower can be used as the operation data to have the cooling ability for the future

  7. 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

  8. 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).

  9. 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)

  10. Evaluation of the effect of cooling towers on the transfer to the ground environment of the tritium from a receiving stream

    International Nuclear Information System (INIS)

    The studies on the impact of the cooling towers (mechanical draught) of the Tihange-1 Nuclear Power Plant, started in 1978. The first study dealt with the evaluation of the transfer in the terrestrial environment of the tritium released in the Meuse River, upstream of the NPP. This study involved, in 1978, four campaigns of plants exposure of one month duration each, two with the cooling towers in operation and two without. In 1979, three campaigns were performed, one with the towers in operation. The results of measurement of the tritium content of the Meuse water, rainwater, water vapor in air as well as the tissue free water (TFWT) of the plants cultivated in the 9 stations have shown that there was no influence, except in one case, due to the operation of the towers, on the levels of TFWT in the exposed plants. Besides, the comparison of the ratios of the specific activities (OBT plant THO rain) does not show a significant difference between the plants, neither between the stations, with or without the towers operating. One sees nevertheless that this ratio has a value ranging from 2.7 to 7.0 which means that an organic 3H source is available for the plant, this does not seem to be the substratum. On the other hand, the OBT contents of the foliage of trees growing on the site and of algae growing in a pond receiving the water from the Meuse are about the same as the values observed in the plants grown at the stations. On the contrary the OBT content of algae growing in the cooling towers are significantly higher (3 to 9 times), which would indicate the presence in the Meuse Water of tritiated organic molecules biologically available. (author)

  11. 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.

  12. 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.)

  13. Tracking of smokestack and cooling tower plumes using wind measurements at different levels

    International Nuclear Information System (INIS)

    Relationships between cooling tower and smokestack plumes at the Bowen Electric Generating Plant in northwestern Georgia and wind direction measurements at levels from the surface at 850 mb (approx. 1.5 km) are examined. The wind measurements play an important role in estimating plume directions which in turn are utilized to establish control and target (upwind and downwind) areas for a study of plant-induced precipitation modification. Fifty-two plume observations were made during a three week period in December 1979. Results indicate that a windset (4.5 km from the plant) mounted at a level approximating that of the cooling tower plume is a better predictor of plume direction than surface windsets (1.0 km from the plant) or 850 mb level winds. However, an apparent topographical influence on the wind direction measurements at the plume-level windset site somewhat limits its plume tracking capability, at least for ambient winds from the SW quadrant

  14. 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.

  15. 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.

  16. 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)

  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. 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%.

  19. 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%.

  20. Modified technique of in-place fungicide treatment of cooling towers as used at the Paducah Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    A modified technique of in-place fungicide treatment of cooling towers has been developed by Union Carbide Corporation, Paducah, Kentucky. The technique enables the fungicide user to treat towers safely without endangering the personnel applying the fungicide. The technique is time saving and effective in obtaining complete coverage of the plenum areas and the decking

  1. 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)

  2. 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

  3. 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...

  4. 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.

  5. 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.).

  6. 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.)

  7. 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 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...

  8. 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.

  9. 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

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

    OpenAIRE

    Andreea-Loreta Cercleux; Florentina-Cristina Merciu; Daniel Peptenatu

    2014-01-01

    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 (tec...

  11. What comes out of the Goesgen cooling tower

    International Nuclear Information System (INIS)

    The results of a poll of 500 people (118 French-speaking Swiss, and 382 German-speaking Swiss) to find out what they think is discharged into the atmosphere by the Goesgen reactor, are discussed. It seems that, in general, the French-speaking Swiss (Romands) think that there is more pollution in the water vapor than do the German-speaking Swiss. (G.T.H.)

  12. Application of modern measuring and data processing instrumentation in the construction of cooling towers in the Mochovce nuclear power plant

    International Nuclear Information System (INIS)

    The specifications are presented of the cooling tower and the calculation is described of the permissible geometric shape deviation. The polar method was used in laying out the cooling tower and the process was based on the local layout network. The least squares method was used in calculating and aligning the coordinates. Digital theodolites were used in measuring the profile. The instruments allowed automating the collection and processing of the measured data. (E.J.)

  13. 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

  14. Comprehensive study of drift from mechanical draft cooling towers. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Laulainen, N.S.; Webb, R.O.; Wilber, K.R.; Ulanski, S.L.

    1979-09-01

    Drift from mechanical draft cooling towers was studied to establish a data base for use in drift deposition model validation. This objective was met by the simultaneous measurement of cooling tower source emission parameters, meteorological variables and drift deposition patterns during seven of eight test runs. Results from six of these test runs are presented and discussed. Source characterization measurements were made of cooling tower emission parameters such as updraft velocity and temperature profiles, liquid and mineral mass drift emission rates, and drift droplet size distributions. The meteorological measurements included wet- and dry-bulb temperature and wind speed and direction at various heights to provide information on the vertical structure of temperature, moisture and mass transport. Surface deposition measurements included both droplet and bulk mineral mass deposition rates. Substantial variation in drift emissions were noticed. Large day-to-day variations for a given cell and large cell-to-cell variations were observed. The problem of deriving a total droplet emission spectrum and rate from one or two towers is complicated and the modeler must decide on the amount of detail he needs to satisfactorily predict downwind deposition patterns. Meteorological conditions during the drift study were characterized by relatively high winds, warm temperatures and moderate humidities. The relatively high winds increased the uncertainty in the measured deposition patterns. In spite of the large (factor of 2 or 3) uncertainty in the measured deposition rates, preliminary calculations of drift deposition rates are in agreement with each other for test run 1. Although the present study did not meet all the requirements for complete validation of various drift models, it has contributed a unique set of data for that purpose.

  15. The development of natural-draught cooling towers of prestressed wire-rope network construction of aerodynamic design

    International Nuclear Information System (INIS)

    Natural-draught cooling towers carried to a height of up to 200 m will be required for the dissipation of the residual heat from the thermal processes of large-capacity power stations to be erected in future. The structural problems involved in such large-size towers can be overcome by using prestressed wire-rope network construction. A structural concept is discussed which proposes to use a cooling tower shell constructed of a prestressed, planked wire-rope network of circular hyperbolic form carried by a spacer ring attached to the central mast. Comments are given on the ensuing problems of aerodynamics, stress-strength assessment, and erection. (orig.)

  16. Cooling clothing utilizing water evaporation

    OpenAIRE

    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 ...

  17. Nuclear cooling tower submitted to shrinkage; behaviour under weight and wind

    International Nuclear Information System (INIS)

    A numerical formulation to analyse nuclear cooling tower submitted to creep and shrinkage of concrete is presented in this paper. Both humidity effects and non-linear mechanical behaviour of the constitutive materials are taken into account. Moisture migration is described using a single diffusion equation in which the relative humidity is the driving force and delayed strains are obtained in a phenomenological way. To capture the time-dependent behaviour, an extension of a continuum plasticity model which incorporates viscous behaviour, has been developed and its main parameters are obtained from experimental results. The effects produced by internal stresses that result from time-dependent deformations are finally presented for nuclear tower under services loading

  18. 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

  19. Interaction between a natural snowfall and a cooling tower plume: an experimental study with a millimetric Doppler radar

    Energy Technology Data Exchange (ETDEWEB)

    Campistron, B.

    1987-01-01

    A precipitation band, about 30 km long and 2 km wide, downwind of a nuclear power plant was observed with a millimetric Doppler radar. The three-dimensional radar analysis showed that this band resulted from the growth, by a seeder-feeder process, of a natural snowfall falling in the moist plume produced by the exhaust of the nuclear plant. At the exit from the 0.6 km deep plume, the mean snow precipitation rate was approximately enhanced by a factor of two. This corresponds to an extraction rate of water in the plume by snow scavenging of 600 kg per second, that is about one third of the water injection rate into the atmosphere by the cooling towers. 13 refs.

  20. 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.

  1. 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.

  2. A Study on Evaluation of Corrosion Properties in cooling tube of water cooling transformers

    International Nuclear Information System (INIS)

    Most of the thirteen substations in operation in the metropolitan area were installed around the year 2000, and since water cooling methods are used to directly withdraw heat from transformer oils, a stable supply of electric power is required through optimal maintenance of facilities. The water cooling tower installed outdoors, which uses the water supply as sprinkler water, experiences the most problems. Since more than 90% of the cooling water is reused, the dissolved composition in the water becomes concentrated due to long operating hours, and impurities dissolve in the water due to air flowing in from the outside, forming hard scales on the outer surface of the cooling tube, and in extreme cases, reacting with the tube material composition, leading to corrosion. As a result, not only is cooling efficiency lowered, but in extreme cases the cooling tube must be replaced. In this study, the characteristics and composition of the scales formed on the cooling tube were analyzed and corrosion characteristics of material types wee identified in order to find an efficient maintenance method for cooling tubes. In addition, the degree of dissolution of various chemicals were investigated during the removal of scales that have been formed

  3. 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

  4. 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)

  5. 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.)

  6. 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.

  7. 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.)

  8. 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

  9. 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)

  10. 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...

  11. Development of an Accident Management Program for the K-Reactor cooling tower at the Savannah River Site

    International Nuclear Information System (INIS)

    This report discusses the Accident Management program at SRS has developed a new methodology for the safe operation of the K-Reactor. This methodology was recently applied during the loss of ultimate heat sink analysis which answers the question of which alternatives are present when the Reactor loses it primary cooling source. With the addition of a new cooling tower there is a need to reapply and perhaps modify the analysis to include the effects of the tower on the existing systems. This process combines the efforts of many different groups. Included in these efforts are interviews with operators, information from documents and drawings, data from computer codes, practice from in-plant drills, and efforts from multi-functional organizations. The central theme of this paper is the explanation of the task involved in the methodology and its application to the cooling tower addition

  12. 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.

  13. Convection towers

    Science.gov (United States)

    Prueitt, Melvin L. (Los Alamos, NM)

    1996-01-01

    Convection towers which are capable of cleaning the pollution from large quantities of air, of generating electricity, and of producing fresh water utilize the evaporation of water sprayed into the towers to create strong airflows and to remove pollution from the air. Turbines in tunnels at the skirt section of the towers generate electricity, and condensers produce fresh water.

  14. WET/DRY COOLING SYSTEMS FOR FOSSIL-FUELED POWER PLANTS: WATER CONSERVATION AND PLUME ABATEMENT

    Science.gov (United States)

    The report gives results of a study of technical and economic feasibilities of wet/dry cooling towers for water conservation and vapor plume abatement. Results of cost optimizations of wet/dry cooling for 1000-MWe fossil-fueled power plants are presented. Five sites in the wester...

  15. Sensitivity study of a method for updating a finite element model of a nuclear power station cooling tower

    International Nuclear Information System (INIS)

    The Research and Development Division of Electricite de France is developing a surveillance method of cooling towers involving on-site wind-induced measurements. The method is supposed to detect structural damage in the tower. The damage is identified by tuning a finite element model of the tower on experimental mode shapes and eigenfrequencies. The sensitivity of the method was evaluated through numerical tests. First, the dynamic response of a damaged tower was simulated by varying the stiffness of some area of the model shell (from 1 % to 24 % of the total shell area). Second, the structural parameters of the undamaged cooling tower model were updated in order to make the output of the undamaged model as close as possible to the synthetic experimental data. The updating method, based on the minimization of the differences between experimental modal energies and modal energies calculated by the model, did not detect a stiffness change over less than 3 % of the shell area. Such a sensitivity is thought to be insufficient to detect tower cracks which behave like highly localized defaults. (author). 8 refs., 9 figs., 6 tabs

  16. 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.

  17. 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.

  18. 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

  19. 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

  20. 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.)

  1. Energy efficiency and system optimization by replacing of water cooled condenser with air cooler in zagros petrochemical complex

    OpenAIRE

    GHOLÄ°POUR, Mohammad

    2015-01-01

    Abstract. In this paper, the feasibility of replacing the water cooled condenser instead air cooler of using disposable technologies once through and cooling tower water is salty and sweet of economic operations is examined. In hot and humid areas of our country like assluyeh, wide temperature changes during the day especially in warm seasons of year affect the atmospheric distillation tower conditions for purification of products both in quantity and quality. This changeable temperature cond...

  2. Operational issues involving use of supplementary cooling towers to meet stream temperature standards with application to the Browns Ferry Nuclear Plant

    International Nuclear Information System (INIS)

    A mixed mode cooling system is one which operates in either the open, closed, or helper (once-through but with the use of the cooling towers) modes. Such systems may be particularly economical where the need for supplementary cooling to meet environmental constraints on induced water temperature changes is seasonal or dependent upon other transient factors such as stream-flow. The issues involved in the use of mixed mode systems include the design of the open cycle and closed cycle portions of the cooling system, the specification of the environmental standard to be met, and the monitoring system and associated decision rules used to determine when mode changes are necessary. These issues have been examined in the context of a case study of TVA's Browns Ferry Nuclear Plant which utilizes the large quantity of site specific data reflecting conditions both with and without plant operation

  3. 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.)

  4. 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.

  5. 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. 

  6. 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.)

  7. Buckling and failure analysis of cooling tower and its application to a real case

    International Nuclear Information System (INIS)

    The paper presents a computational model for reinforced concrete multilayered shell element taking into account geometrical and physical non-linearities. The shell element results from the superposition of a plate element based on the discretization of the Mindlin theory, and the CST element. The initial curvature is incorporated using the Marguerre shallow shell theory. The constitutive model for the uncracked concrete is based on the elastoplastic theory and for the cracked concrete a tension softening behaviour is assumed. The description of the motion is made in the corotational Lagrangian formulation. The numerical part of the paper contains a detailed study of a built cooling tower. It is shown that the buckling load resulting from linear prebuckling analysis is considerably larger than the ultimate load. (author)

  8. Fuzzy Logic Application for Optimization of the Cooling Towers Control System

    CERN Document Server

    Blanc, D

    2000-01-01

    The control system for the SPS-BA6 cooling towers station is considered in order to introduce the concept of a multivariable process. Multivariable control means the maintenace of several controlled variables at independent set points. In a single-variable system, to keep the single process variables within their critical values is considered a rather simple operation. In a complex multivariable system, the determination of the optimal operation point results in a combination of all set values of the variables. Control of a multivariable system requires therefore a more complex analysis. As the solution based on a mathematical model of the process is far beyond acceptable complexity, most mathematical models involve extensive simplifications and linearizations to optimize the resulting controllers. In this report the author will demonstrate how fuzzy logic might provide elegant and efficient solutions in the design of multivariable control based on experimental results rather than on mathematical models.

  9. 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)

  10. 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)

  11. 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

  12. 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

  13. 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)

  14. 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.)

  15. 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)

  16. TESTING AND ANALYSIS OF A WET-DRY CROSSFLOW COOLING TOWER, VOLUME I: TEST PROGRAM AND RESULTS

    Science.gov (United States)

    The report discusses the test program and performance analysis of a single-cell mechanical-draft wet/dry cooling tower in Cliffside, NC. Objectives of the program were to obtain performance data and results on mass transfer, heat transfer, fluid flow, plume formation, and acousti...

  17. 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)

  18. 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

  19. 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)

  20. 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.)

  1. 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.

  2. 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.

  3. 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.)

  4. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Gold, H.; Goldstein, D.J.; Yung, D.

    1976-07-01

    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.

  6. 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

  7. 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)

  8. 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.)

  9. 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.)

  10. 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)

  11. 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...

  12. Cooling water practices at coal and gas based power stations

    International Nuclear Information System (INIS)

    Water is used for a number of diverse purposes in a power plant. In most cases, the water cannot be used as such and requires treatment to ensure higher efficiency and protection of equipment. Corrosion, scale deposition and fouling have since long posed as challenges to the technical expertise of cooling water chemists at industrial and utility power plants. The study of the raw water, water samples from the CW tower basin and clarified water of various coal and gas based power stations has indicated that problem of corrosion and scale formation are linked with the quality of raw water and operating parameters. The present paper deals with the different cooling water treatment practices being followed at various power stations and which have been quite helpful in improving the quality of water and reduce scale promotion, thereby improving heat transfer of condenser and heat exchangers, and in addition to prevent corrosion in the pipelines, water boxes, tube plates and condenser tubes. The above said studies constitutes a part of the Research work being carried out by corrosion group of Research and Development Centre, NTPC under the project entitled evaluation of standards for cooling water treatment which has been sanctioned under CBIP (Central Board of Irrigation and Power) action plan by Department of Power to Research and Development Centre of NTPC in the 8th plan period. (author)

  13. 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 locations--Delaware River Basin (Philadelphia), Michigan/Great Lakes (Detroit), Ohio River Valley (Indianapolis), South (Atlanta), and Southwest (Yuma)--were modeled using an ASPEN simulator model. The model evaluated the performance and energy penalty for hypothetical 400-MW coal-fired plants that were retrofitted from using once-through cooling systems to wet- and dry-recirculating systems. The modeling was initially done to simulate the hottest time of the year using temperature input values that are exceeded only 1 percent of the time between June through September at each modeled location. These are the same temperature inputs commonly used by cooling tower designers to ensure that towers perform properly under most climatic conditions.

  14. 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.

  15. 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)

  16. 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)

  17. 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.)

  18. 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)

  19. 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.)

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

    Directory of Open Access Journals (Sweden)

    Amir-Samimi

    2013-04-01

    Full Text Available 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 receiving effluent and will cause pollution. Conversely, microorganisms that are present in the water cooling system that can be bad effects on the corrosion and deposition create operational efficiencies.

  1. Pulsed cooling-water systems for actively cooled beam dumps

    International Nuclear Information System (INIS)

    A pulsed water system offers an economically attractive way of supply cooling water for beam dumps, as the water flow and pressure requirements increase. A pilot system was built and used in testing prototype beam dumps. Operating experience gained with the pulsed water system has proved the feasibility of this design

  2. Water quality control and analysis of the secondary cooling system in HANARO

    International Nuclear Information System (INIS)

    The secondary cooling system in HANARO includes the chemical injection system. The cooling system has a basin, a cooling tower with four cooling fans, three cooling pumps of 50% capacity, related valves, pipings and instruments. The chemical injection system has two tanks containing different kinds of chemicals, four injection pumps, related valves and pipings. The cooling method is mechanical induced drift type. While the cooling water is circulating, the heat is transmitted to the cooling water in the exchangers and emitted into the often air by forced draft in the cooling tower. Due to the loss of cooling water by evaporation, various kinds of undesirable substances such as salts in solution and micro organisms are accumulated in the cooling water, and they could result in defects such as corrosion, scale, and slime in the system. Therefore, the causes of degradation such as corrosion, scale, and slime are restrained by injection of the chemicals into the cooling water, and the concentration of chemicals is controlled by the periodic blowdown of the cooling water. While the blowdown is nothing but discharging the water out of the system for the control of the cooling water quality, it causes increasing the amount of waste of service water on the contrary. To avoid such counter effect of the blowdown function, the system to operate without blowdown was considered and investigated. Should the system be realized about 100 tons of service water is expected to be saved every working day. In this report, the basic theory is described about the water quality control for the secondary cooling water. The validity and the amount of chemicals being used were reviewed to maintain the water quality. The overall situation of water quality control were analysed as well by reviewing of the quality of cooling water between 1997 and 1999. Furthermore the relation between the number of cycles and the rate of loss of cooling water was confirmed to demonstrate that the secondary cooling water can be managed by high Ca-hardness treatment without blowdown to minimize the loss of cooling water

  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. Replacement of the cooling tower packing at the Goesgen-Daeniken AG nuclear power plant; Ersatz der Kuehlturmeinbauten im Kernkraftwerk Goesgen-Daeniken

    Energy Technology Data Exchange (ETDEWEB)

    Rich, Hans Walter [Kernkraftwerk Goesgen-Daeniken AG, Daeniken (Switzerland)

    2012-07-01

    In 2005 the asbestos cement cooling tower packing was replaced by plastic material. Two years later, the packing showed strong deformations, deposits of solids and weight gain. At the end of 2007 parts of the packing collapsed into the cooling tower basin. Investigations were made, revealing that the thickness of the packing foil was too low and that packing geometry and biofilms on the surface of the packing favoured deposition of solids. Successful measures were taken to solve the problems. (orig.)

  6. 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...

  7. Water cooled pebble bed reactor

    International Nuclear Information System (INIS)

    Nuclear energy is expected to contribute largely to the worldwide future electricity supply. However, the severe incidents in Three Mile Island / Harrisburg and Tschernobyl have lead to stricter requirements concerning safety aspects as well as final disposal. Therefore new safety concepts are investigated worldwide. The fulfilment of nuclear, thermal, chemical and mechanical stability in each operating state is an essential demand in the new concepts. The development of this innovative reactor is motivated by some general considerations, which transfer the safety characteristics of spherical fuel elements, known from the HTR-technology, to reactors using different cooling media. The use of water as coolant implies the advantage of using advanced primary and secondary circuit technology of existing pressurized-water reactors (PWRs) of western type that are currently at work. Besides thermal-hydraulic parameters of PWRs and therefore high thermal outputs can be obtained. (orig.)

  8. 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.

  9. Cooling water for SSC experiments: Supplemental Conceptual Design Report (SCDR)

    International Nuclear Information System (INIS)

    This paper discusses the following topics on cooling water design on the superconducting super collider; low conductivity water; industrial cooling water; chilled water systems; and radioactive water systems

  10. 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)

  11. 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

  12. Substitution of cooling tower components in the nuclear power plant Goesgen-Daeniken AG; Ersatz der Kuehlturmeinbauten im Kernkraftwerk Goesgen-Daeniken AG

    Energy Technology Data Exchange (ETDEWEB)

    Rich, H.W. [Kernkraftwerk Goesgen-Daeniken AG (Switzerland)

    2011-07-01

    At the nuclear power plant Goesgen-Daeniken AG (Daeniken, Switzerland), the cooling tower installations of asbestos cement to have been replaced by plastics. The resulting continuous decrease in the cooling capacity is based on a weakly dimensioned wall thickness of the film installations and on a deposition of suspended matter. The deposition of suspended matter additionally was favoured by biofilms on the film surface. Four measures are presented for the remediation of this problematic situation. With this, the contamination of the film installations are minimized. Deformations of foil packets can be avoided. The cooling capacity of the cooling tower significantly has been improved.

  13. 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

  14. 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.

  15. 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

  16. 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

  17. 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)

  18. 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

  19. 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)

  20. 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