WorldWideScience

Sample records for cooling tower water

  1. Device for cooling down cooling water especially in cooling towers

    A cooling tower is described where water runs over packing plates being cooled by steaming air. In the cooling process a combination of wet and dry cooling is applied, namely by special design of the packing plates which are arranged inclined to the vertical. Spraying device and packing plates are shaped in such a way that the plates are wetted almost on one side only. 13 drawings explain the construction of the device described in detail. (UWI)

  2. Asbestos in cooling-tower waters

    Lewis, B.A.G.

    1977-12-01

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

  3. Light water nuclear power station with dry cooling tower

    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

    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. Isolation of Legionella pneumophila from Cooling Tower Water by Filtration

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

    1981-01-01

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

  6. Cooling towers

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

  7. Asbestos in cooling-tower waters. Final report

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

    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.)

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

    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

  10. Cooling tower

    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)

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

    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.

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

    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

  13. Complex development of cooling towers

    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

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

    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

  15. Numerical study of coupled heat and mass transfer in geothermal water cooling tower

    Cross flow mechanical cooling towers, widely spreads all over the south region of Tunisia are used for cooling geothermal water for agriculture and domestic ends. These towers are sized empirically and present several problems in regard to operation and electrical energy consumption. This work aims to study the thermal behaviour of this type of cooling towers through a developed mathematical model considering the variation of the water mass flow rate inside the tower. The analysis of the water and air temperatures distribution along the cooling tower had underlined the negative convection phenomenon at a certain height of the tower. This analysis has shown also that the difference in water temperature between the inlet and the outlet of the tower is much higher than the one of air due to the dominance of the evaporative potential compared to the convective one. In addition, the variations of the air humidity along the cooling tower and the quantity of evaporated water have been investigated. The loss of water by evaporation is found to be 5.1% of the total quantity of water feeding the cooling tower. Interesting future prospects are expected for validation of the developed model to optimize the operating of the cooling tower

  16. Ecological impact of chloro-organics produced by chlorination of cooling tower waters

    Jolley, R L; Cumming, R B; Pitt, W W; Taylor, F G; Thompson, J E; Hartmann, S J

    1977-01-01

    Experimental results of the initial assessment of chlorine-containing compounds in the blowdown from cooling towers and the possible mutagenic activity of these compounds are reported. High-resolution liquid chromatographic separations were made on concentrates of the blowdown from the cooling tower at the High Flux Isotope Reactor (HFIR) and from the recirculating water system for the cooling towers at the Oak Ridge Gaseous Diffusion Plant (ORGDP), Oak Ridge, Tennessee. The chromatograms of chlorinated cooling waters contained numerous uv-absorbing and cerate-oxidizable constituents that are now being processed through a multicomponent identification procedure. Concentrates of the chlorinated waters are also being examined for mutagenic activity.

  17. Comparative technical-economical investigation for a counter-flow cooling tower fitted with water collectors

    The paper points out the investigation of a high capacity cooling tower fitted with water collectors, compared with the conventional constructive variant. It is the Romanian concerns with respect to cutting down the cooling tower power consumption that are investigated by means of updated overall expenses method

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

    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

  19. Cooling tower and environment

    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.)

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

    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.

  1. Cooling towers of electric power generation plants

    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

  2. Evaluation Of Cooling Tower Degradation

    Cooling tower degradation has been evaluated for the last 10 years. Its heat transfer capacity has been decreasing after several years of operation due to aging. Evaluation is carried out by calculating the degradation rate, namely the annual increase of outlet temperatures of the cooling tower. Data was randomly taken daily at 15 MW reactor power. Data was taken after the reactor operation of ± 8 hours. Evaluation since 1990 shows that the degradation rate is nearly one degree per year. This degradation can be by minimized, replacement of damaged components, non-excessive operation and design modification of the cooling tower namely by extending the period of contract between water and air

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

    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.

  4. Water tower

    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.

  5. An operational experience with cooling tower water system in chilling plant

    Cooling towers are popular in industries as a very effective evaporative cooling technology for air conditioning. Supply of chilled water to air conditioning equipments of various plant buildings and cooling tower water to important equipments for heat removal is the purpose of chilling plant at PRPD. The cooling medium used is raw water available at site. Water chemistry is maintained by make-up and blowdown. In this paper, various observations made during plant operation and equipment maintenance are discussed. The issues observed was scaling and algal growth affecting the heat transfer and availability of the equipment. Corrosion related issues were observed to be less significant. Scaling indices were calculated to predict the behavior. (author)

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

    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

  7. Hydraulic works study of Golfech cooling towers

    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

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

    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.

  9. Legionella fairfieldensis sp. nov. isolated from cooling tower waters in Australia.

    Thacker, W L; Benson, R F; Hawes, L; Gidding, H; Dwyer, B; Mayberry, W R; Brenner, D.J.

    1991-01-01

    Three Legionella-like organisms were isolated from water from the cooling towers of two Australian institutions. The strains grew on buffered charcoal-yeast extract (BCYE) agar but not on BCYE agar in the absence of L-cysteine. Gas-liquid chromatography profiles of the isolates were consistent with those for Legionella spp. They were serologically distinct from other legionellae in a slide agglutination test. DNA hybridization studies showed that the three isolates belong to a new species of ...

  10. Plumes from one and two cooling towers

    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

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

    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.

  12. The future cooling tower; Fremtidens koeletaarn

    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)

  13. Cooling tower with forced convection

    Using air or magnetic cushions and linear motor drives, frictional losses as well as noise and wear are reduced, so that a blower of large mass can rotate economically and with high efficiency at the point where the cooling tower diameter is largest. This blower at the basis of the cooling tower consists of an endless blade row between two rotating ring elements of cooling tower diameter. (HP)

  14. Hydraulic cooling tower driver

    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

  15. Induced draught circular cooling tower

    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

  16. Large cooling tower drift deposition

    A model for the determination of drift deposition around natural-draft cooling towers is presented. An application of the model in actual operating conditions indicates the effect of drift rate at the cooling tower outlet and weather conditions on the size and shape of wetted area. (author)

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

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

  18. Cooling towers principles and practice

    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

  19. Statistics Analysis Measures Painting of Cooling Tower

    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...

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

    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

    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

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

    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.

  4. Cooling towers in the landscape

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

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

    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.

  6. Frost protection for atmospheric cooling tower

    When the atmospheric temperature is near or lower than zero it is necessary to reduce the air flow entering in a cooling tower. A wire netting mounted on the air inlet is sprinkled with cold water. The level of the ice curtain and consequently the air flow is regulated by aspersion by hot water

  7. Cooling Tower Overhaul of Secondary Cooling System in HANARO

    HANARO, an open-tank-in-pool type research reactor of 30 MWth power in Korea, has been operating normally since its initial criticality in February, 1995. For the last about ten years, A cooling tower of a secondary cooling system has been operated normally in HANARO. Last year, the cooling tower has been overhauled for preservative maintenance including fills, eliminators, wood support, water distribution system, motors, driving shafts, gear reducers, basements, blades and etc. This paper describes the results of the overhaul. As results, it is confirmed that the cooling tower maintains a good operability through a filed test. And a cooling capability will be tested when a wet bulb temperature is maintained about 28 .deg. C in summer and the reactor is operated with the full power

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

    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.

  9. Improved facility and sensitivity in the use of guinea pigs for the isolation of Legionella pneumophila from cooling tower water.

    Leinbach, E D; Winkler, H H; Wood, D O; Coggin, J. H.

    1983-01-01

    The established criteria for the determination of the optimum time for the sacrifice of guinea pigs inoculated with samples of cooling tower water were found to be inadequate for the detection of low levels of Legionella pneumophila. By ignoring the requirement for fever and by sequentially sacrificing the infected guinea pigs on days 3 through 5 postinoculation, we simplified the procedure, and the sensitivity of detection was improved a great deal.

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

    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)

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

    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.)

  12. Improving the efficiency of natural draft cooling towers

    Oman, Janez; Širok, Brane; Smrekar, Jure

    2015-01-01

    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 wateržair mass flow ratio and ensures the homogeneity of the heat transfer and a reduction ofentropy generation, thus minimising th...

  13. Vortex-augmented cooling tower-windmill combination

    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.

  14. Numerical simulation of counter-flow wet-cooling towers

    Heidarinejad, Ghassem; Karami, Maryam [Department of Mechanical Engineering, Tarbiat Modares University, P.O. Box 14115-143, Tehran (Iran); Delfani, Shahram [Building and Housing Research Center (BHRC), P.O. Box 13145-1696, Tehran (Iran)

    2009-08-15

    Cooling towers are used to cool a warm water stream through evaporation of part of the water into an air stream. A cooling tower consists of three zones; namely spray, packing and rain zones. In cooling towers, a significant portion of the total heat rejected may occur in the spray and rain zones. These zones are modeled and solved numerically using a computer code. The developed models of these zones are validated against experimental data. For the case study under consideration, the error in calculation of the tower volume is 1.5% when the spray and rain zones are neglected. This error is reduced to 1.1% and 0.25% as the spray and rain zones are incorporated in the model, respectively. Furthermore, the effect of the Lewis factor on the performance prediction of wet-cooling towers is investigated using Bosnjakovic equation. (author)

  15. Side Stream Filtration for Cooling Towers

    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.

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

    Minnoş, Bihter; Ilhan-Sungur, Esra; Çotuk, Ayşın; Güngör, Nihal Doğruöz; 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

  17. Dynamic interaction effects in cooling tower groups

    A theoretical and experimental determination of the dynamic response of reinforced concrete cooling towers, taking into consideration group effects, are described. The results for an individual tower are thoroughly examined. A complete analysis is then performed for the critical wind orientations, for each tower in a six towers group. It's shown that ignoring group effects in the analysis may lead to a significant underestimation of the structural response. (E.G.)

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

    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

  19. Studies on the conditioning of line-decarbonized cooling-tower make-up feedwater for use as secondary cooling water

    Conditioned Danube water is used in the Gundremmingen nuclear power plant, units B + C, for cooling conventional cooling sites (service water) prior to its application as cooling-tower make-up feedwater. Conditioning is effected by decarbonization using lime (2Ksub(S8.2) proportional Ksub(S4.3); pH proportional 10) with subsequent dosing of hardness stabilizers. The pipelines of the service water system are made of non-alloy non-coated steel and the heat exchanger tubes are largely made of special-grade brass 71 and pure copper. The occurrence of sludge-like deposits in the heat exchanger tubes and strong, partly blister-type formation of deposits on the ferritic pipe surfaces during commissioning caused the examination of different conditioning methods in a test cooling facility while simulating real conditions at 'on-site' operation. One single product out of the range of conditioners tested did not exhibit the formation of sludge-type deposits on the heat exchanger tubes, thus rendering any extra chlorination unnecessary to-date. Assessment of the corrosion behaviour of the C-steel showed operation with decarbonized water at pH proportional 10 to be superior to those employing a reduced pH. (orig./RB)

  20. Cooling tower drift: comprehensive case study

    A comprehensive experiment to study drift from mechanical drift cooling towers was conducted during June 1978 at the PG and E Pittsburg Power Plant. The data from this study will be used for validation of drift deposition models. Preliminary results show the effects of tower geometry and orientation with respect to the wind and to single- or two-tower operation. The effect of decreasing relative humidity during a test run can also be seen

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

    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.)

  2. Design Of Cooling Tower And Standard Of Technical Test

    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.

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

    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.

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

    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

  5. Causes and control of cooling tower film fill deposits

    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

  6. Dry cooling tower operating experience in the LOFT reactor

    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

  7. Dry cooling tower operating experience in the LOFT reactor

    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.

  8. Structure of natural draft cooling towers, 1

    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.)

  9. Determination of the replacement cooling tower capability at the ETRR-2 research reactor

    The ETRR-2 replacement cooling tower capability has been evaluated by the thermal acceptance test performed in June 2003. All instruments used were calibrated prior to the test. The measured data are collected at regular intervals in accordance with the acceptance test code for water cooling towers of the cooling tower institute recommendations. Both the characteristic curve and the performance curve methods were used to evaluate the tower capability. The test results yield a tower capability of about 105% and so the tower is thermally accepted. (orig.)

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

    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

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

    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.

  12. The shape of natural draft cooling towers

    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

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

    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

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

    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)

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

    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.

  16. Experiences with a parametrised cooling-tower plume model

    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)

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

    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

  18. European dry cooling tower operating experience

    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

    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. Analytical Assessment of Environmental Impact for APR1400DC UHS Cooling Tower

    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

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

    Lee, Jaiho [KHNP-Central Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    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.

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

    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...

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

    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.

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

    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

  5. Electrocoagulation to Remove Silica from Cooling Towers Water / Electrocoagulacin para remover slice en agua de torres de enfriamiento

    Ivn Emmanuel, Villegas-Mendoza; Alejandra, Martn-Domnguez; Sara, Prez-Castrejn; Silvia Lucila, Gelover-Santiago.

    2014-06-01

    Full Text Available El presente artculo muestra los resultados de un estudio que se llev a cabo para evaluar el efecto de la calidad del agua en la remocin de slice disuelto mediante un proceso de electrocoagulacin utilizando electrodos de aluminio. El slice 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 electrocoagulacin (EC), floculacin, sedimentacin y filtracin en arena. Se estudiaron dos RW y CTBW, con caractersticas fisicoqumicas diferentes. Las variables de respuesta analizadas fueron las siguientes: eficiencia del aluminio para remover slice (relacin mgl-1 de Al3+ dosificado/mgl-1 de slice removido), eficiencia de remocin de Al3+ dosificado, prdida de carga hidrulica a travs del reactor electroqumico y el voltaje. Se calcul el costo del tratamiento de los cuatro tipos de agua. La relacin mgl-1 de Al3+ dosificado/mgl-1 de slice removido oscil 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 energa, sustancias qumicas y consumo de electrodos para el tratamiento de RW oscil 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

    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. Measurements on cooling tower plumes. Pt. 3

    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.)

  8. Interception and retention of simulated cooling tower drift by vegetation

    A key issue concerning environmental impacts from cooling tower operation is the interception of drift by vegetation and the efficiency of plants in retaining the residue scavenged from the atmosphere. Chromated drift water, typical of the cooling towers of the Department of Energy's uranium enrichment facilities at Oak Ridge, Tennessee, was prepared using radio-labelled chromium. A portable aerosol generator was used to produce a spectrum of droplets with diameters (100 to 1300 μ) characteristic of cooling towers using state-of-the-art drift eliminators. Efficiency of interception by foliage varied according to leaf morphology with yellow poplar seedlings intercepting 72% of the deposition mass in contrast to 45% by loblolly pine and 24% by fescue grass. Retention patterns of intercepted deposition consisted of a short-time component (0 to 3 days) and a long-time component (3 to 63 days). Retention times, estimated from the regression equation of the long component, indicated that drift contamination from any deposition event may persist from between 8 and 12 weeks. In field situations adjacent to cooling towers, the average annual concentration of drift on vegetation at any distance remains relatively constant, with losses from weathering being compensated by chronic deposition

  9. Susceptibility of Legionella pneumophila to three cooling tower microbicides.

    Grace, R D; Dewar, N E; Barnes, W. G.; Hodges, G R

    1981-01-01

    Investigation of epidemic outbreaks of Legionnaires disease by Center for Disease Control personnel has resulted in the isolation of Legionella pneumophila from water in the air-conditioning cooling towers or evaporative condensers at the site of the outbreak. It is suspected that improperly maintained open, recirculating water systems may play a role in the growth and dissemination of this pathogen. The objective of this study was to determine the antimicrobial activity of three chemically d...

  10. Rainfall enhancement due to scavenging of cooling tower condensate

    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

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

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

    Highlights: ? Simulation of cooling tower performance under different operating conditions. ? Cooling tower performance is simulated using ASPEN PLUS. ? LevenbergMarquardt 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 LevenbergMarquardt 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.

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

    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.

  14. Stiffened cooling tower shells of reinforced concrete

    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.)

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

    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

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

    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

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

    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...

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

    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

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

    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

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

    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

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

    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.

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

    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.

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

    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%

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

    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

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

    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

  6. Replacement of diffusers on JRR-3 secondary cooling tower

    The secondary cooling tower of JRR-3 is a facility for dissipating/cooling the heat generated in the reactor core by receiving it via heat exchanger, and the secondary cooling tower diffuser is a facility to efficiently dissipate this heat to atmosphere. Since this equipment had passed 25 years since its establishment, and the corrosion due to aging deterioration was significant, the updating of the equipment was planned aimed at contributing to long-term safety and the stable operation of JRR-3. This paper describes the overview of entire reactor cooling system facility, and the inspection maintenance and performance of the secondary cooling tower. As the improvements in the updating of the secondary cooling tower diffuser, this paper describes the consideration of paints and quality of the base material, and the improvement of inspection port and base frame opening. It also reports the fabrication of these devices, dismantling of existing equipment, and installation of the new diffuser. (A.O.)

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

    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

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

    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

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

    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

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

    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.)

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

    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.)

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

    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

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

    Iigo-Golfn, 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.

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

    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...

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

    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)

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

    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.

  17. On the possibility of a ''dry'' cooling tower application for the APS condensators with a dissociating coolant

    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

  18. Gust factors for hyperbolic cooling towers on soils

    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

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

    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 Merkels method witch integrated in TRNSYS. The results of optimization using TRNSYS are validated by several theoretical and experimental studies

  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

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

    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

  3. Coupling model and solving approach for performance evaluation of natural draft counter-flow wet cooling towers

    Wang Wei

    2016-01-01

    Full Text Available When searching for the optimum condenser cooling water flow in a thermal power plant with natural draft cooling towers, it is essential to evaluate the outlet water temperature of cooling towers when the cooling water flow and inlet water temperature change. However, the air outlet temperature and tower draft or inlet air velocity are strongly coupled for natural draft cooling towers. Traditional methods, such as trial and error method, graphic method and iterative methods are not simple and efficient enough to be used for plant practice. In this paper, we combine Merkel equation with draft equation, and develop the coupled description for performance evaluation of natural draft cooling towers. This model contains two inputs: the cooling water flow, the inlet cooling water temperature and two outputs: the outlet water temperature, the inlet air velocity, equivalent to tower draft. In this model, we furthermore put forward a soft-sensing algorithm to calculate the total drag coefficient instead of empirical correlations. Finally, we design an iterative approach to solve this coupling model, and illustrate three cases to prove that the coupling model and solving approach proposed in our paper are effective for cooling tower performance evaluation.

  4. A simulation software for cooling towers optimal operation

    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.

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

    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.

  6. Evaluation of the RSG-GAS cooling tower performance

    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

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

    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.)

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

    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.

  9. 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

    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.

  10. Predicted climatology of cooling tower plumes from energy centers

    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

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

    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

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

    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)

  13. Tower Water-Vapor Mixing Ratio

    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.

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

    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)

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

    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

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

    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.

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

    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

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

    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

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

    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.)

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

    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)

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

    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.)

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

    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.

  3. EDF's ageing management program for cooling towers

    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)

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

    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

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

    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)

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

    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)

  7. Legionella control in cooling towers by electrolytic disinfection

    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.)

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

    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.)

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

    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

    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. Cooling tower drift: experiment design for comprehensive case study

    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

  12. Recent developments in the design of large cooling towers

    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)

  13. 40 CFR 61.134 - Standard: Naphthalene processing, final coolers, and final-cooler cooling towers.

    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...

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

    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

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

    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.

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

    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

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

    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.

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

    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

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

    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

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

    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.)

  1. Anomalous snowfall caused by natural-draft cooling towers

    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

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

    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.

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

    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.

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

    Zuniga-Gonzalez, Israel; Maršík, František

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

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

    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

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

    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.

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

    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

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

    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.

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

    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

  10. Rainfall enhancement due to scavenging of cooling tower condensate

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

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

    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

  12. N3S-AERO. A multidimensional model for numerical simulation of flows in cooling towers

    In order to obtain a better estimation of thermal efficiency as well as a good description of local phenomena in cooling towers, a specific version of EDF's industrial finite element code N3S, denoted N3S-AERO, has been developed for the simulation of flows in cooling towers. It allows to model obstructed zones by directional head losses tensors and fans using their characteristic curves. A single model might include up to 20 towers (with their components - e.g. anti-freeze system - and their environmental exterior domain) in al kinds of configuration (counter flows with recuperators or with rain zones, cross flows, or any combination). The present paper describes the governing equations for air and water flows as well as the numerical algorithms used. Validation is carried out on some configurations of cooling tower in 2D and 3D geometries, showing the ability of N3S-AERO to predict major physical phenomena. Global results on thermal performance are compared with results of the 1D code TEFERI or experimental data when available. Further validation is underway to achieve finer comparison with experimental data for large industrial configurations. (author)

  13. Nuclear power plant without cooling towers combined with a pumped storage facility

    In meeting the load requirements of the power grid it is very advantageous to combine a thermal power plant with a hydroelectric plant to cover peak loads. The report deals with a nuclear power plant combined with a pumped storage plant with two pools as the cooling and storage pools. This installation would not even need cooling towers, because of the extensive use made of the waste heat for agricultural application, hot water preparation, etc. The heated cooling water is collected downstream of the condenser and passed through various greenhouses, swimming pools, floor heating systems etc., cooled on its way and passed on to the other pool, where it is returned to the condenser of the nuclear power plant for cooling purposes. This concept, which is suggested as a basis for discussion, not only offers advantages in terms of ecology and energy utilization, but also represents a major strategic safety item in energy supply in case of war. (orig.)

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

    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

  15. Mathematical modelling of the atmospheric distribution of cooling tower plumes

    The 3 D model KASTEL is presented which gives a realistic description of the physical processes in cooling tower plumes. Partial differential equations are used as balances of mass, momentum, and energy. The flow field is calculated using the eddy transport equation and Poisson's current function equation. The Reynolds shear stresses and turbulent flows of enthalpy and moisture are described by a complex turbulence model which solves differential equations for turbulence energy, its dissipation rate, and the covariances of enthalpy and moisture. (orig./HP)

  16. Wind induced vibrations of reinforced concrete cooling tower shells

    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)

  17. Operational cost minimization in cooling water systems

    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.

  18. Operational cost minimization in cooling water systems

    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.

  19. Comparison of the efficacy of free residual chlorine and monochloramine against biofilms in model and full scale cooling towers.

    Türetgen, Irfan

    2004-04-01

    The presence of microbial cells on surfaces results in the formation of biofilms, which may also give rise to microbiologically influenced corrosion. Biofilms accumulate on all submerged industrial and environmental surfaces. The efficacy of disinfectants is usually evaluated using planktonic cultures, which often leads to an underestimate of the concentration required to control a biofilm. The aim of this study was to investigate the efficacy of monochloramine on biofilms developed in a cooling tower. The disinfectants selected for the study were commercial formulations recommended for controlling microbial growth in cooling towers. A cooling tower and a laboratory model recirculating water system were used as biofilm reactors. Although previous studies have evaluated the efficacy of free chlorine and monochloramine for controlling biofilm growth, there is a lack of published data concerning the use monochloramine in cooling towers. Stainless steel coupons were inserted in each tower basin for a period of 30 d before removal. Monochloramine and free chlorine were tested under identical conditions on mixed biofilms which had been allowed to grow on coupons. Monochloramine was found to be significantly more effective than free chlorine against cooling tower biofilms. PMID:15203961

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

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

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

    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.

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

    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

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

    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.

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

    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.)

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

    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

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

    Lijie Li

    2015-10-01

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

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

    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 ...

  8. Numerical study on the cooling performance of natural draft dry cooling tower with vertical delta radiators under constant heat load

    Highlights: • A 3D numerical model for NDDCTV under constant heat load was set and validated. • The ambient temperature effect on NDDCTV under constant heat load had been studied. • A suitable crosswind profile index was ascertained by sensitivity analysis. • The crosswind effect on NDDCTV under constant heat load has studied from columns. • The crosswind effect mechanism was clarified from the air inflow deviation angle. - Abstract: From the view of cooling system, the natural draft dry cooling tower with vertical delta radiators (NDDCTV) under constant heat load can be studied by keeping constant water temperature drop Δtw. With computed entry water temperature tw1 as the sum of tower exit water temperature tw2 and the constant Δtw, a three-dimensional (3D) numerical model for NDDCTV under constant heat load was established. Through analyses about mesh-independence, sensitivity about crosswind profile index and comparison with published results, the accuracy and credibility of the established numerical model for NDDCTV were confirmed. The aerodynamic field around cooling deltas was analyzed at windless and crosswind conditions, so as to clarify the impacts of ambient air temperature and air inflow deviation angle θd on the performance of cooling columns. With constant heat load and uniform entry water temperature, the cooling performance of each sector was analyzed under crosswind impact. With increasing crosswind velocity vc, the cooling performance of NDDCTV under constant heat load deteriorates sharply at low vc, but varies slightly at high vc, which can be improved by air deflectors

  9. Fog and drift deposition from evaporative cooling towers

    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

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

    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

  11. Demineralised water cooling in the LHC accelerator

    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.

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

    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

  13. 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

    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.

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

    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.)

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

    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.

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

    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

  17. Girassol, Riser Towers for ultra deep water

    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.

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

    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.

  19. Water cooled nuclear reactor

    The description is given of a water cooled nuclear reactor comprising a core, cooling water that rises through the core, vertical guide tubes located inside the core and control rods vertically mobile in the guide tubes. In this reactor the cooling water is divided into a first part introduced at the bottom end of the core and rising through it and a second part introduced at the top end of the guide tubes so as to drop in them

  20. Geodetic works on the construction of cooling tower of TEŠ 6

    Kolarič, Andrej

    2014-01-01

    The thesis discusses with geodetic works on the construction of cooling tower of sixth block in Šoštanj thermal power plant. It presents briefly the thermal power plant and describes the process of construction of the cooling tower. The establishment of basic surveying network stakeout is explained. It is also contains a full description of the stakeout procedures. Paper states the requirements and accuracy of stakeout and describes practical examples. It shows the concrete implementation ...

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

    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.

  2. 3D simulation of air flow and heat transfers in cooling towers

    Physical phenomena in cooling towers are complex and often diminish the efficiency of the turbine. So, in order to better understand the air flow and heat transfers phenomena in the exchange areas of existing cooling towers, EDF has developed a 3D CFD code named N3S-AERA. Furthermore the impact of new components or technologies could be computed and the results help us to understand the behaviour of the flow. (authors)

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

    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

  4. Numerical analysis on overall performance of Savonius turbines adjacent to a natural draft cooling tower

    Highlights: • New application for Savonius turbine is presented. • Turbine can improve cooling efficiency of a cooling tower like a windbreaker. • New arrangement is useful from thermal and power generation viewpoints. - Abstract: Two large Savonius turbine have been proposed to use near the radiators of a natural draft dry cooling tower instead of previously proposed solid windbreakers. A numerical procedure has been used to predict the flow field unsteadily, and calculate the cooling improvement and power generation in turbines. Numerical results showed that rotating turbines could improve cooling capacity as the same order of solid windbreakers. It was surprisingly concluded that presence of cooling tower near Savonius turbine increased its power generation. Ultimately, it was concluded that overall improvement of the proposed arrangement was considerable from thermal and clean energy production viewpoints

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

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

    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.)

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

    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

  8. Climatic uncertainty in Himalayan water towers

    Mishra, Vimal

    2015-04-01

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

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

    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)

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

    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

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

    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

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

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

    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

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

    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...

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

    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.

  16. Environmental assessment of Chalk Point cooling tower drift and vapor emissions

    Davis, E.A.

    1979-03-01

    An assessment is provided of selected environmental effects of operating the cooling towers and stacks of Units No. 3 and No. 4 of the Potomac Electric Power Company's generating station at Chalk Point, Maryland. The emphasis is on the magnitude of salt deposition to the area surrounding the cooling tower due to saline water drift. A secondary but important consideration is the magnitude of salt loading due to saline drift from the stack which uses saline river water in scrubbing flue gases. This salt loading together with that of the ambient salt background is assessed for its effects on soils, crops, native vegetation and man-made structures. Other atmospheric effects examined are: enhancement of ground level fogging and icing, enhancement of precipitation, and the flight hazards to aircraft. A numerical model of drift deposition has been developed and validated against the data collected in the Dyed Drift Experiment at Chalk Point. Use of the available data model predictions indicate that with fulltime, full load operation of both 600 MW(e) units significant levels of salt deposition occur only on the plant site within 0.4 km of the source. The predicted maximum salt deposition rates are given. The effects on soils, crops and native vegetation are predicted to be negligible at off-site locations. Significant effects to foliage of dogwood is predicted to occur at the most impacted on-site locations. Corrosion of structures at these locations could be enhanced under conditions of heavy plant operation. Enhancement of ground-level fogging, icing, and precipitation is expected to be negligible for all conditions of plant use. Hazards to aircraft because of restricted visibility, turbulence, and icing of structures and engines are estimated to be very slight and of no consequence.

  17. Water-cooled electronics

    Dumont, G; Righini, B

    2000-01-01

    LHC experiments demand on cooling of electronic instrumentation will be extremely high. A large number of racks will be located in underground caverns and counting rooms, where cooling by conventional climatisation would be prohibitively expensive. A series of tests on the direct water cooling of VMEbus units and of their standard power supplies is reported. A maximum dissipation of 60 W for each module and more than 1000 W delivered by the power supply to the crate have been reached. These values comply with the VMEbus specifications. (3 refs).

  18. N3S-AERO: a multidimensional model for numerical simulation of all wet cooling tower systems

    3D model is more required to optimize the design of new cooling tower by way of parameters studies, to improve the performance of the existing ones from changes in fill zone or water distribution. Therefore, the Directions des Etudes et Recherches with collaboration of the Direction de l'Equipement of EDF, has developed a specific version of the finite element CFD code N3S, denoted N3S-AERO, for the simulation of natural or mechanical draught wet cooling towers. It solves mass, momentum, heat and humidity averaged Navier-Stokes equations including buoyancy terms with variable density for air flow in the whole domain mass, heat equations for water flow in exchange zones. With standard results of N3S as air velocity and scalar fields, N3S-AERO gives in return water temperature fields mean values of variables at inlet or outlet of each exchange zone and thermal performance of the tower. 2D axisymmetrical and 3D industrial cases have soon been done. Major flow phenomena are well predicted and averaged cold water values are in good agreement with ID-TEFERI code or measurements

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

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

    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

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

    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.)

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

    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

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

    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)

  4. Thermal Characteristics of Heating Towers

    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.

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

    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

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

    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 2030 % for the deflectors angle a=60o. Simulation let one analyze aerodynamic patterns, induced inside cooling tower and homogeneity of velocities field in irrigators area.Presented results may be helpful for the CT aerodynamic design optimization, particularly, for perspective hybrid type CTs.

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

    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

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

    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...

  9. Sea water for cooling Koeberg

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

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

    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.)

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

    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)

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

    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

  13. Cooling clothing utilizing water evaporation

    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. T...

  14. 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)

    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.)

  15. Water Cooled Mirror Design

    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.

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

    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.

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

    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

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

    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

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

    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.

  20. Light water cooled reactor

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

    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

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

    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.

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

    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

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

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

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

    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

  6. The new cooling tower principle Matrix-Multiflow; Das neue Kuehlturmprinzip Matrix-Multiflow

    Juran, H. [Technisches Pressebuero, Koenigswinter (Germany); Plocki, O. [Marley Kuehlturm GmbH, Duesseldorf (Germany)

    1995-11-01

    All cooling tower construction built so far can be assigned fluidically to the cross-flow or counterflow principle. The new Matrix-Multiflow System, which was developed in cell-construction with ducted aeration for large cooling capacities of the industry and energy economy, corresponds basically to none of the two principles, even if constructively it represents a modified cross-flow tower with cross-flow film internals. In the following the development, function, construction, defined properties and application demand of this patented cooling tower principle is described. It takes over adn extends the typical advantages of the cross-flow principle and minimizes the disadvantages with regard to the counterflow principle. (orig.) [Deutsch] Alle bisher gebauten Kuehlturmausfuehrungen lassen sich stroemungstechnisch dem Kreuz- oder Gegenstromprinzip zuordnen. Das neue Matrix-Multiflow-System, das in Zellenbauweise mit Zwangsbelueftung fuer grosse Kuehlleistungen der Industrie und Energiewirtschaft entwickelt wurde, entspricht im Grunde keinem der beiden Prinzipien, auch wenn es konstruktiv einen modifizierten Kreuzstromturm mit Kreuzstromfilmeinbauten darstellt. Nachfolgend werden Entwicklung, Funktion, Ausfuehrung, markante Eigenschaften und Anwendungsbedarf dieses patentierten Kuehlturmprinzips beschrieben. Es uebernimmt oder erweitert die typischen Vorteile des Kreuzstromprinzips und minimiert die Nachteile gegenueber dem Gegenstromprinzip weitgehend. (orig.)

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

    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...

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

    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

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

    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.)

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

    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

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

    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.

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

    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.)

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

    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

  14. Acidity of vapor plume from cooling tower mixed with flue gases emitted from coal-fired power plant.

    Hlawiczka, Stanislaw; Korszun, Katarzyna; Fudala, Janina

    2016-06-01

    Acidity of products resulting from the reaction of flue gas components emitted from a coal-fired power plant with water contained in a vapor plume from a wet cooling tower was analyzed in a close vicinity of a power plant (710m from the stack and 315m from the cooling tower). Samples of this mixture were collected using a precipitation funnel where components of the mixed plumes were discharged from the atmosphere with the rainfall. To identify situations when the precipitation occurred at the same time as the wind directed the mixed vapor and flue gas plumes above the precipitation funnel, an ultrasound anemometer designed for 3D measurements of the wind field located near the funnel was used. Precipitation samples of extremely high acidity were identified - about 5% of samples collected during 12months showed the acidity below pH=3 and the lowest recorded pH was 1.4. During the measurement period the value of pH characterizing the background acidity of the precipitation was about 6. The main outcome of this study was to demonstrate a very high, and so far completely underestimated, potential of occurrence of episodes of extremely acid depositions in the immediate vicinity of a coal-fired power plant. PMID:26950639

  15. Cooling clothing utilizing water evaporation

    Sakoi, Tomonori; Tominaga, Naoto; Melikov, Arsen Krikor; Kolenckov, 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 ...

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

    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.

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

    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.

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

    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

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

    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

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

    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.

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

    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

  2. Convection towers

    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.

  3. 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.

    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...

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

    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

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

    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

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

    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.

  7. Increase in the turbulent diffusion of pollutants by cooling tower plumes

    Measurements in the vicinity of wet natural-draught cooling towers of large output, carried out with the help of a power glider, show that the atmospheric turbulence can increase drastically within the range of influence of the plumes. If the flue gases from a stack reach this region of increased turbulence they are more rapidly diluted; this can result in appreciable changes in the ground concentration of the precipitated pollutants. Impairment is then greater in the immediate vicinity of the power plant and lower in more remote areas. To enable allowance to be made for this influence when estimating the effects on the environment averaged over a year, the extent to which the plume increases vertical diffusion was investigated. (Auth.)

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

    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.)

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

    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)

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

    GHOLİPOUR, 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...

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

    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)

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

    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...

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

    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)

  14. Water Towers, City of Darlington Water Towers, Published in 2006, 1:24000 (1in=2000ft) scale, Lafayette County Land Records.

    NSGIC GIS Inventory (aka Ramona) — This Water Towers dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Field Survey/GPS information as of 2006. It is described as...

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

    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)

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

    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.

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

    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

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

    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.

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

    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.)

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

    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)

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

    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.

  2. Cooling tower, construction method method therefor and precast prestressed concrete building units

    A large, thin-shell cooling tower, a method for its erection, and novel precast units are described. Upon a foundation a series of angularly-extending columns is erected, and the columns are joined at their upper ends by a lower ring. Then a ribbed, waffle-like reinforced concrete wall is constructed to extend up from the lower ring and to provide a shell with a shape such as a hyperbolic paraboloid. The ribbed outer (or inner) surface strengthens the structure while enabling the thickness of the portions in between the ribs to be relatively thin. A series of vertically-spaced horizontal circumferential reinforcing bars or post-tensioning cables and a series of horizontally-spaced vertical or inclined bars or cables are included in the wall. The wall is preferably made up from a series of precast units that are of novel structure in themselves. At the top of the wall is an upper ring joining the various elements together

  3. Water cooling of RF structures

    We present computer codes for heat transfer in water cooled rf cavities. RF parameters obtained by SUPERFISH or analytically are operated on by a set of codes using PLOTDATA, a command-driven program developed and distributed by TRIUMF [1]. Emphasis is on practical solutions with designer's interactive input during the computations. Results presented in summary printouts and graphs include the temperature, flow, and pressure data. (authors). 4 refs., 4 figs

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

    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)

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

    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)

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

    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)

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

    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.

  8. 18 CFR 420.44 - Cooling water.

    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...

  9. Cooling water for Koeberg nuclear power station

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

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

    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.

  11. Possibility of decreasing pollutant emissions from coke quenching towers by water curtains

    Teper-Szczypiorowska, Z. (Huta Czestochowa, Czestochowa (Poland))

    1992-07-01

    Describes advantages of water curtains applied to reduce air pollution during coke quenching. Three possible constructions of quenching towers were presented: pocket type tower, multi-stage closed cycle tower, and continuous quenching tower. A quenching tower equipped with a water curtain at a coking plant in the Czestochowa Steelworks is described. Emissions from this tower were measured at its outlet to the atmosphere (height of 40 m) and at 29 m height. Spacing of spraying nozzles is shown in a figure. Apart from dust emission, such gases as nitrogen oxides, carbon monoxide, sulfur dioxide and hydrogen sulfide were also investigated with the use of a computer controlled analyzer. Additionally, concentrations of aliphatic and aromatic hydrocarbons were chromatographically determined. The tests involved water curtains operating at full capacity, at lower capacity, and quenching towers with no curtain at all. The water curtain solution was found capable of reducing dust emissions by 78%, hydrogen sulfide by 31%, carbon monoxide by 27%, sulfur dioxide by 43% and nitrogen oxides by 88%. The emission rate is highest at the very beginning of quenching, so it is sufficient to operate the curtain for the first 2 min. 15 refs.

  12. Implications of Transitioning from De Facto to Engineered Water Reuse for Power Plant Cooling.

    Barker, Zachary A; Stillwell, Ashlynn S

    2016-05-17

    Thermoelectric power plants demand large quantities of cooling water, and can use alternative sources like treated wastewater (reclaimed water); however, such alternatives generate many uncertainties. De facto water reuse, or the incidental presence of wastewater effluent in a water source, is common at power plants, representing baseline conditions. In many cases, power plants would retrofit open-loop systems to cooling towers to use reclaimed water. To evaluate the feasibility of reclaimed water use, we compared hydrologic and economic conditions at power plants under three scenarios: quantified de facto reuse, de facto reuse with cooling tower retrofits, and modeled engineered reuse conditions. We created a genetic algorithm to estimate costs and model optimal conditions. To assess power plant performance, we evaluated reliability metrics for thermal variances and generation capacity loss as a function of water temperature. Applying our analysis to the greater Chicago area, we observed high de facto reuse for some power plants and substantial costs for retrofitting to use reclaimed water. Conversely, the gains in reliability and performance through engineered reuse with cooling towers outweighed the energy investment in reclaimed water pumping. Our analysis yields quantitative results of reclaimed water feasibility and can inform sustainable management of water and energy. PMID:27077957

  13. 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

    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.

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

    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

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

    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

  16. Water cooled pebble bed reactor

    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.)

  17. European supercritical water cooled reactor

    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.

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

    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

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

    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.

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

    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

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

    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

  2. Johnson screen for cooling water intakes

    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

  3. Efficient Water Management in Water Cooled Reactors

    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

  4. Water Cooled FBNR Nuclear Reactor

    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)

  5. Electricity production with low grade heat in thermal power plants by design improvement of a hybrid dry cooling tower and a solar chimney concept

    Highlights: • A system of a dry cooling tower and a solar chimney are recombined. • The hot flue gas is injected in the hybrid tower to maximize the power output. • Effects of the angle of the tower walls (convergent or divergent) are studied. • Effects of the collector roof slope and base ground slope are studied. • The thermal efficiency of a 250 MW power plant is increased more than 0.5%. - Abstract: In this study, an improved concept design is presented to increase the thermal efficiency of the Rankine cycle of a typical steam power plant by combining a solar chimney and a dry cooling tower. The sources of the wind energy generation, include: the rejected heat from condenser to the air entering dry cooling tower, solar radiation and the airlift pumping effect on the air flow created by the stack hot flue gas which is injected into the hybrid tower as a novel change. This research primarily focuses on the Shahid Rajaee 250 MW steam power plant to determine the velocity of generated flow at the turbine inlet; a numerical finite volume code was employed for a dry cooling tower having a base diameter and a chimney height of 250 and 200 m, respectively. Calculations have been iterated for different angles of chimney walls, slopes of collectors and the base ground to find their effects on the output power. A range of 360 kW to more than 4.4 MW power is captured by the wind turbine by changing the hybrid tower geometrical parameters. Obtained results reveal a maximum of 0.538% increase for the thermal efficiency of the fossil fuel power plant

  6. Passive cooling means for water cooled nuclear reactor plants

    This patent describes a water cooled, nuclear fission reactor plant having an improved auxiliary passive cooling system for dissipating heat produced during periods of other than normal operation, the nuclear fission reactor plant. It comprises the combination of: a reactor pressure vessel containing a core of heat producing fissionable fuel material provided with reciprocally removable fission control rods and having external steam and hot coolant water conduits extending out therefrom including a circulation loop passing through a heat exchanger comprising a steam driven turbine, the reactor pressure vessel and adjacent components being housed within an enclosing, substantially gas impermeable containment structure for retaining a gaseous atmosphere enveloping the reactor pressure vessel and adjacent components; a container retaining a pool of cooling water isolated from the atmosphere of the containment structure and positioned at a level within the containment structure above the reactor pressure vessel, the isolation container including a heat exchanger unit submerged in the retained pool of cooling water having an inlet which is in optional fluid communication with the interior of the reactor pressure vessel and with the atmosphere of the containment structure enveloping the pressure vessel; a suppression pool chamber containing a pool of cooling water for condensing steam positioned adjacent to the reactor pressure vessel and having a horizontal vent passing to an adjoining area which is in open communication to the atmosphere of the containment structure; a vent duct extending from an outlet of the heat exchanger unit submerged in the isolation container pool downward into the suppression pool chamber with its open end terminating below the surface of the cooling water pool and above the level of the horizontal vent passing an adjoining area

  7. Three decades of experience with cooling water system of a fast reactor

    The cooling water system constitutes the terminal heat exchange system for the fast breeder test reactor (FBTR) which is a sodium cooled fast reactor of 40 MWt capacity. It transfers the residual heat to atmosphere through a cooling tower. Cooling water system of FBTR comprises two sub-systems namely condenser cooling water system and service water system. Condenser cooling water is circulated through main condenser, dump condenser, condensate cooler, generator air cooler and turbine oil cooler. Service water system removes heat from several heat exchangers of auxiliary systems like air compressor, cold trap cooling, nitrogen plant, Biological Shield Cooling (BSC), Diesel Generator (DG) and steam-water system sample coolers. The cooling water system consists of an open recirculating type with an induced draft cooling tower as the ultimate heat sink. Initially, Palar river water was used as the cooling medium. At present, due to scarcity of river water, sub soil water and output from Nuclear Desalination Demonstration Plant (NDDP) are also used as cooling water. The material of construction of pipe line is carbon steel and the heat exchanger tube and other equipment materials are copper, admiralty brass, aluminium brass, bronze, Cu-Ni and carbon steel. The construction of the cooling water system of FBTR was completed in 1980. Since then the sub-systems were commissioned one by one. Whenever a sub system was commissioned, it generated a lot of impurities which affected the existing treatment programme. Sodium hexa meta phosphate treatment, Langelier Index monitoring, chlorination, global and target dispersant addition at high heat flux heat exchanger, chemical cleaning of corroded pipelines, corrosion monitoring, side stream filtration, addition of phosphonate-based corrosion inhibitor, broad spectrum biocide and specific biocide for iron oxidising bacteria are some of the phases of the cooling water treatment programme. At present, corrosion rates are generally less than 3 mpy for carbon steel and less than 0.5 mpy for brass. This paper details the challenges faced and remedial measures implemented in the cooling water system of FBTR for better performance and increased availability. (author)

  8. Steam-Electric Power-Plant-Cooling Handbook

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

    1982-02-01

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

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

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

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

    A. Ataei

    2009-01-01

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

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

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

  12. Proposal for an alternative operative method for determination of polarisation resistance for the quantitative evaluation of corrosion of reinforcing steel in concrete cooling towers

    Mitzithra, M.E., E-mail: me.mitzithra@gmail.com [EDF R& D, 6 quai Watier, 78401 Chatou Cedex (France); Université de Toulouse, UPS, INSA, LMDC, 135, Avenue de Rangueil, 31077 Toulouse Cedex 4 (France); Deby, F.; Balayssac, J.P. [Université de Toulouse, UPS, INSA, LMDC, 135, Avenue de Rangueil, 31077 Toulouse Cedex 4 (France); Salin, J. [EDF R& D, 6 quai Watier, 78401 Chatou Cedex (France)

    2015-07-15

    This paper summarises the results obtained from numerical simulations of an operational measurement mode of polarisation resistance adapted for evaluating corrosion of reinforcing steel in concrete on cooling towers. A simple operational measurement mode of R{sub p} is proposed, adapted for cooling towers prone to corrosion due to carbonation. By means of numerical experimentations, calculation diagrams and semi-empirical equations are built involving the different influencing parameters: concrete cover to steel reinforcement, concrete resistivity and current intensity injected from the counter electrode. Finally, a first application of the proposed procedure for calculating the real value of R{sub p} in laboratory conditions is presented.

  13. Proposal for an alternative operative method for determination of polarisation resistance for the quantitative evaluation of corrosion of reinforcing steel in concrete cooling towers

    This paper summarises the results obtained from numerical simulations of an operational measurement mode of polarisation resistance adapted for evaluating corrosion of reinforcing steel in concrete on cooling towers. A simple operational measurement mode of Rp is proposed, adapted for cooling towers prone to corrosion due to carbonation. By means of numerical experimentations, calculation diagrams and semi-empirical equations are built involving the different influencing parameters: concrete cover to steel reinforcement, concrete resistivity and current intensity injected from the counter electrode. Finally, a first application of the proposed procedure for calculating the real value of Rp in laboratory conditions is presented

  14. "Hot" for Warm Water Cooling

    IBM Corporation; Energy Efficient HPC Working Group; Hewlett Packard Corporation; SGI; Cray Inc.; Intel Corporation; U.S. Army Engineer Research Development Center; Coles, Henry; Ellsworth, Michael; Martinez, David J.; Bailey, Anna-Maria; Banisadr, Farhad; Bates, Natalie; Coghlan, Susan; Cowley, David E.; Dube, Nicholas; Fields, Parks; Greenberg, Steve; Iyengar, Madhusudan; Kulesza, Peter R.; Loncaric, Josip; McCann, Tim; Pautsch, Greg; Patterson, Michael K.; Rivera, Richard G.; Rottman, Greg K.; Sartor, Dale; Tschudi, William; Vinson, Wade; Wescott, Ralph

    2011-08-26

    Liquid cooling is key to reducing energy consumption for this generation of supercomputers and remains on the roadmap for the foreseeable future. This is because the heat capacity of liquids is orders of magnitude larger than that of air and once heat has been transferred to a liquid, it can be removed from the datacenter efficiently. The transition from air to liquid cooling is an inflection point providing an opportunity to work collectively to set guidelines for facilitating the energy efficiency of liquid-cooled High Performance Computing (HPC) facilities and systems. The vision is to use non-compressor-based cooling, to facilitate heat re-use, and thereby build solutions that are more energy-efficient, less carbon intensive and more cost effective than their air-cooled predecessors. The Energy Efficient HPC Working Group is developing guidelines for warmer liquid-cooling temperatures in order to standardize facility and HPC equipment, and provide more opportunity for reuse of waste heat. This report describes the development of those guidelines.

  15. Thermal calculations for water cooled research reactors

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

  16. Importance of biological monitoring of cooling waters

    In 2007, technical recommendation 'Biological monitoring of cooling waters I-F-23' was issued in the Czech Republic, which is addressed namely to operators and attending personnel of water cooling systems and similar equipment. The attention is paid to the biological problems and to the specification of biological methods (introduction into the subject matter, picked indicators, practice of determination and evaluation respectively, follow-up outline). Further are mentioned the characteristics of water-cooling facilities with the intent to inform likewise the biology specialists, which may face the aforesaid topic. (author)

  17. Environmental assessment of cooling reservoirs

    The environmental impacts, both adverse and beneficial, of cooling reservoirs are compared to cooling towers as an alternative closed cycle cooling system. Generally, the impacts associated with the construction of a cooling reservoir system are greater than for a comparable cooling tower system. Operational impacts are generally greater for cooling towers due to their visual impact, plus icing, fogging, and noise problems. The principle advantages of cooling reservoirs are their lower operating and maintenance costs, greater reliability, greater cooling efficiency, reduced water consumption in areas where cooling water storage is required, and their multiple use potential. A review of pertinent literature on cooling reservoir ecosystems, has revealed that entrainment, thermal, and chemical effects generally result in reduced populations of phytoplankton, zooplankton, and benthos in the vicinity of the power plant discharge. Adverse far field effects are generally less significant and are sometimes stimulatory. The overall effects of a power plant on the fish populations of cooling reservoirs appear to be minor. Based on the thermal characteristics of a model 6400 acre cooling reservoir with four 1150 MWe reactors, the ecological characteristics of the reservoir were predicted. The multiple use possibilities of cooling reservoirs provide their most significant beneficial aspect when compared to cooling towers. In addition, the cage culture of food fishes in cooling reservoirs provides an economical and practical method of commercially utilizing the waste heat discharged by power plants. For many areas of the country, cooling reservoirs appear to provide an environmentally and socially desirable alternative to cooling towers

  18. Fouling of cooling tower film fill: Causes, cleanup techniques and operating guidelines to minimize reoccurrence

    Robinette, D.J.; Puckorius, P.R. [Puckorius and Associates, Inc., Evergreen, CO (United States)

    1996-10-01

    The old adage an ounce of prevention is worth a pound of cure could not be more appropriate than in the case of film fill fouling. It is relatively easy to keep new film fill from fouling if a good chemical treatment program is established from day one. On the other hand, if fill becomes fouled, it often goes undetected until the problem has progressed to such an extent that--at best, the tower performance is severely impaired, or--at worst, a portion of the tower collapses from the weight of the deposit. It is usually an extremely difficult, costly, and time-consuming task to restore the fill`s cleanliness under the latter circumstances. It requires proper foulant diagnosis and development of an effective cleanup procedure, but restoration to near 100% cleanliness can be achieved. This paper discusses the phenomenon of film fill fouling from a perspective developed through numerous actual case histories in which the authors were called in to diagnose and correct the problem.

  19. Mathematical Model of Two Phase Flow in Natural Draft Wet-Cooling Tower Including Flue Gas Injection

    Hyhlík, Tomáš

    2016-03-01

    The previously developed model of natural draft wet-cooling tower flow, heat and mass transfer is extended to be able to take into account the flow of supersaturated moist air. The two phase flow model is based on void fraction of gas phase which is included in the governing equations. Homogeneous equilibrium model, where the two phases are well mixed and have the same velocity, is used. The effect of flue gas injection is included into the developed mathematical model by using source terms in governing equations and by using momentum flux coefficient and kinetic energy flux coefficient. Heat and mass transfer in the fill zone is described by the system of ordinary differential equations, where the mass transfer is represented by measured fill Merkel number and heat transfer is calculated using prescribed Lewis factor.

  20. Experiences with generator stator water cooling

    In large generators heat losses are removed by water cooling. To allow this, the stator bars and in many cases also the rotors contain hollow conductors bearing the cooling water. This report will focus on stator water cooling and the behaviour of hollow conductor materials in the generator cooling water. We originally used copper as hollow conductor material, but, since 1973, also stainless steel. As a standard, we operate all our generators in high-purity water without any additives, and under minimized low-oxygen conditions. We have not encountered any problems with reduction in the integrity of the hollow conductors by corrosion in the cooling water. On the other hand, copper can produce copper-oxides which may impair the cooling water flow through the narrow channels of the hollow conductors. This is a phenomenon we have observed in son of our generators and which is also reported by other manufactures Stainless steel hollow conductors do not produce such oxides and are therefore spared from this phenomenon. (authors)

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

    1977-01-01

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

  2. Meteorological effects of the cooling towers at the Oak Ridge Gaseous Diffusion Plant. II. Predictions of fog occurrence and drift deposition

    The frequency of occurrence of fogs and the rate of deposition of chromate due to emissions from the cooling towers at the Oak Ridge Gaseous Diffusion Plant are calculated. Observations of drift deposition agree fairly well with calculated values. A detailed summary of significant findings is given

  3. Flow Stability of Supercritical Water Cooled Systems

    Research activities are ongoing worldwide to develop nuclear power plants with supercritical water cooled reactor (SCWR) with the purpose to achieve a high thermal efficiency and to improve their economical competitiveness. However, the strong variation of the thermal-physical properties of water in the vicinity of the pseudo-critical line results in challenging tasks in thermal-hydraulic design of a SCWR. One of the challenging tasks is to understand and to predict the dynamic behavior and flow stability of supercritical water cooled systems. Although extensive thermal-hydraulic research activities have been carried out worldwide, studies on flow stability of SC water cooled systems are scarce. The present study deals with the flow behavior of SC water cooled systems. For this purpose the computer code SASC was developed, which is applied to a simplified cooling system. The effect of various parameters on the flow behavior is investigated. The first results achieved up to now reveals a complicated dynamic performance of a system cooled by supercritical water. (authors)

  4. Water injection device of cooling water and nuclear reactor

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

  5. Air and water cooled modulator

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

    1995-01-01

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

  6. Outbreak of legionnaires' disease from a cooling water system in a power station (Heysham)

    In September and October 1981 six cases of pneumonia occurred among men working in a power station under construction. Three were identified as cases of legionella pneumonia and two others had serology suggestive of legionella infection. In a sample of 92 men from the site 10 had low levels of antibodies to legionella; a similar sample of men working on an adjacent site showed none with positive serology. In a case control study it was found that cases of pneumonia were more likely than controls to have worked on a part of the site where four small capacity cooling towers were located. Legionella pneumophila serogroup 1 was isolated from the water systems of these four towers but was not found in samples from any other cooling towers or hot or cold water outlets on the site. It would appear that there was airborne spread of the organism from these cooling water systems which had not received conventional treatment to inhibit corrosion and organic growth. This is the first outbreak of legionnaires' disease to be recorded in an industrial setting in the United Kingdom. No cases of legionella infection have occurred on the site since the introduction of control measures. (author)

  7. Cooling water cleaning for steam turbine condensers

    The design of filters for cooling water cleaning for steam turbine condensers are described. It is pointed out that mounting of additional filters before the condensers particularly in case of contaminated water and crag development in the circulation system is economically justified. Additional filters are mounted in combination with the system of ball cleaning of condenser tubes as well as independently of it

  8. Climate change will affect the Asian water towers.

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

    2010-06-11

    More than 1.4 billion people depend on water from the Indus, Ganges, Brahmaputra, Yangtze, and Yellow rivers. Upstream snow and ice reserves of these basins, important in sustaining seasonal water availability, are likely to be affected substantially by climate change, but to what extent is yet unclear. Here, we show that meltwater is extremely important in the Indus basin and important for the Brahmaputra basin, but plays only a modest role for the Ganges, Yangtze, and Yellow rivers. A huge difference also exists between basins in the extent to which climate change is predicted to affect water availability and food security. The Brahmaputra and Indus basins are most susceptible to reductions of flow, threatening the food security of an estimated 60 million people. PMID:20538947

  9. Laboratory observations of biocide efficiency against Legionella in model cooling tower systems

    Thomas, W.M.; Eccles, J.; Fricker, C.

    1999-07-01

    The efficacy of specific oxidizing and non-oxidizing biocides was examined using a model cooling system inoculated with a microcosm containing an environmental isolate of Legionella pneumophila. The microcosm was prepared in a two-stage chemostat, which provided a consistent source of microbiological inoculum for the study. The microcosm consisted of both sessile (within biofilms) and planktonic Legionella in association with other microorganisms, including Pseudomonas species and cyst-forming ameobae. A procedure was established to successfully transfer the chemostat grown inoculum to the model cooling system and establish both sessile and planktonic forms of Legionella in the model cooling system. The greatest biocidal effect for all of the biocides was observed immediately after dosing. This effect was relatively short-lived even for the slow acting biocides such isothiazolin (as 8 ppm active) where an effect was only observed over the first 12 hours. The faster acting biocides, DBNPA (as 8 ppm active) and gluteraldehyde (as 27 ppm active), did initially reduce Legionella populations but did not totally eliminate Legionella or provide lasting control. Chlorine and bromine (as 0.5--1.5 ppm free halogen), and ozone (as 0.1--0.5 ppm free reserve) reduced and controlled Legionella populations so long as a free reserve of oxidant was maintained. Legionella recovered quickly after biocide dosing, reestablishing similar levels to those observed before dosing.

  10. Materials for advanced water cooled reactors

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

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

    Shcherbakov Vladimir Ivanovich

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

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

    Gary Vine

    2010-12-01

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

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

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

  14. Water Towers, Published in 2000, 1:1200 (1in=100ft) scale, City of Fort Wayne.

    NSGIC GIS Inventory (aka Ramona) — This Water Towers dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Hardcopy Maps information as of 2000. Data by this publisher are...

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

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

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

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

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

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

  18. Thermohydraulic relationships for advanced water cooled reactors

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

  19. The atmospheric cooling of nuclear power stations

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

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

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

  1. Analysis of water cooled reactors stability

    A model for stability analysis of non-boiling water cooled nuclear system is developed. The model is based on linear reactor kinetics and space averaged heat transfer in reactor and heat-exchanger. The transfer functions are defined and the analysis was applied to nuclear reactor RA at 'Boris Kidric' Institute - Vinca. (author)

  2. Mixed oxide fuel for water cooled reactors

    The problems connected with introduction of plutonium extracted from spent fuels of operating NPPs into water cooled reactor fuel cycle are considered. The trends in formation of the World market of mixed fuel are illustrated taking as examples Great Britain and Japan

  3. Subchannel analysis of supercritical water cooled reactors

    Subchannel analysis of supercritical water cooled reactors is carried out for estimating hot channel factors. A subchannel code for supercritical-water cooled reactors is developed. It is verified by comparing the calculated result of ASFRE-III code. The outlet coolant and cladding temperature are sensitive to the local power peaking and the assembly flow maldistribution because of the large coolant density change and high sensitivity of coolant temperature to the enthalpy change above the pseudo-critical temperature. However, it is shown that the effect is mitigated when the area of the peripheral subchannels is reduced and the mixing is enhanced 4-8 times of ordinary value at the grid spacers. The hot channel factor of a high temperature supercritical pressure light water cooled fast reactor (SCFR-H) is calculated using the uncertainties of Clinch River Breeder Reactor Plant (CRBRP). The factor is slightly higher than that of CRBRP because of the characteristics of supercritical water. The sensitivities of the hot channel factor is decreased for the SCFR-H fuel assembly in the core with blankets cooled by descending flow because of the higher inlet temperature of the driver fuel assemblies. (author)

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

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

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

    Amir-Samimi

    2013-01-01

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

  6. Evaporative cooling of speleothem drip water

    M. O. Cuthbert; G. C. Rau; M. S. Andersen; H. Roshan; Rutlidge, H.; Marjo, C. E.; M. Markowska; Jex, C.N.; Graham, P. W.; Mariethoz, G.; R. I. Acworth; Baker, A.

    2014-01-01

    This study describes the first use of concurrent high-precision temperature and drip rate monitoring to explore what controls the temperature of speleothem forming drip water. Two contrasting sites, one with fast transient and one with slow constant dripping, in a temperate semi-arid location (Wellington, NSW, Australia), exhibit drip water temperatures which deviate significantly from the cave air temperature. We confirm the hypothesis that evaporative cooling is the dominant, but so far una...

  7. Supercritical-pressure light water cooled reactors

    Oka, Yoshiaki

    2014-01-01

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

  8. Water cooled FBNR nuclear reactor

    Full text: The world with its increasing population and the desire for a more equitable and higher standard of living, is in the search for energy that is abundant and does not contribute to the problem of global warming. The answer to this is a new paradigm in nuclear energy; i.e., through the innovative nuclear reactors that meet the IAEA's INPRO philosophies and criteria that will guarantee the generation of safe and clean energy. The emerging countries to nuclear energy that are not in hurry for energy and look into the future are looking into the participation in the development of such innovative nuclear reactors. They can start developing the non-nuclear components of such reactors in parallel with creating the nuclear infra-structures according to the guidelines of the IAEA suggested in its milestones document. In this way, they can benefit from numerous advantages that the development of a high technology can bring to their countries be it scientific, technological, economic or political. A solution to the present world economic crisis is investing in such projects that contribute to the real economy rather than speculative economy. This will help both local and world economy. One such innovative nuclear reactor is the FBNR that is being developed with the support of the IAEA in its program of Small Reactors Without On-site Refuelling. It is a small (70 MWe) reactor with simple design based on the proven PWR technology (www.sefidvash.net/fbnr). The simplicity in design and the world wide existence of water reactor technology, makes it a near term project compared to other future reactors. Small reactors are most adequate for both the developing and developed countries. They require low capital investment, and can be deployed gradually as energy demand calls for. The generation of energy at the local of consumption avoids high cost of energy transmission. The paradigm of economy of scale does not apply to the FBNR as it is a small reactor by its nature. The FBNR enjoys the economy of mass production. FBNR can serve a dual purpose plant generating electricity and producing desalinated water at the same time at lower cost. The FBNR has been evaluated by the IAEA's INPRO Methodology from the safety and nonproliferation points of view and is shown to be a fool proof reactor against nuclear proliferation and have inherent safety against any conceivable accident. The reactor has in its upper part the reactor core and a steam generator and in its lower part the fuel chamber. The core consists of two concentric perforated zircaloy tubes of 31 cm and 171 cm in diameters, inside which, during the reactor operation, the spherical fuel elements are held together by the coolant flow in a fixed bed configuration, forming a suspended fixed core. The coolant flows vertically up into the inner perforated tube and then, passing horizontally through the fuel elements and the outer perforated tube, enters the outer shell where it flows up vertically to the steam generator. The reserve fuel chamber is a 60 cm diameter tube made of high neutron absorbing alloy, which is directly connected underneath the core tube. The fuel chamber consists of a helical 40 cm diameter tube flanged to the reserve fuel chamber that is sealed by the national and international authorities. A grid is provided at the lower part of the tube to hold the fuel elements within it. A steam generator of the shell-and-tube type is integrated in the upper part of the module. A control rod can slide inside the centre of the core for fine reactivity adjustments. The reactor is provided with a pressurizer system to keep the coolant at a constant pressure. The pump circulates the coolant inside the reactor moving it up through the fuel chamber, the core, and the steam generator. Thereafter, the coolant flows back down to the pump through the concentric annular passage. At a flow velocity called terminal velocity, the water coolant carries the 15 mm diameter spherical fuel elements from the fuel chamber up into the core. A fixed suspended core is formed in the reactor. In

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

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

  10. Mixing systems for wet and dry plumes and cleaning equipment for the heat exchangers of the dry section. Two indispensible components of an effective and safe hybrid cooling tower

    At first glance, the hybrid cooling tower seems to be an ingenious combination of the well known components of an evaporative cooling tower and a dry cooling tower. The calculation of the air mass flows for both the wet and dry sections required to achieve an invisible plume does not represent an unsolvable problem to the engineer experienced in thermodynamics. The same also applies to the dimensioning of the heat exchangers and cooling fills. The hybrid cooling tower requires a well designed mixing system in order to ideally mix, the dry plume into the wet plume. If the cooling tower proves its efficiency during commissioning it is important that the ratio of the performance of the wet section to that of the dry section be maintained also in the long term. The performance of the fill in a wet cooling tower is consistently stable. Dirt deposits can form very quickly on the inner and outer surfaces of the heat exchangers of the dry section. In this case the thermal resistance increases rapidly. The respective performance of the wet and dry sections is then no longer balanced and the invisibility of the plume is no longer assured. This can be avoided by providing appropriate cleaning equipment

  11. One year full-scale study of ozone cooling water treatment at a German electric power station

    This paper presents operating results of ozone treatment of the water in a cooling system with open loop recycling containing the following elements: Main cooling water pumps - Cooling water storage tanks - Distribution manifold to cooling water users - Cooling water collecting basins - Cooling water recycling pumps - Cooling tower. The system reviewed in this paper is the side cooling system of a heating power station in Germany, with a capacity of 1,000 m3/h (4,400 US gpm). Operation started in early 1989. The plant has been operating now for over two (2) years. During this period the following items were analyzed and evaluated: Ozone residual in the water - Quality of the cooling water - Organic scaling on equipment and piping - Material corrosion behavior. For the purpose of analyzing the corrosion behavior, two heat exchangers were installed, both identical and each fitted with tubes of different materials. One unit was in contact with ozone residual, while the other was exposed to water without ozone. The results of this two year operation are extremely encouraging and the owner of the power plant decided to keep the ozone system operating for the future. 3 refs., 7 figs., 1 tab

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

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

  13. Validation of an In-Water, Tower-Shading Correction Scheme

    Hooker, Stanford B. (Editor); Firestone, Elaine R. (Editor); Doyle, John P.; Zibordi, Giuseppe; vanderLinde, Dirk

    2003-01-01

    Large offshore structures used for the deployment of optical instruments can significantly perturb the intensity of the light field surrounding the optical measurement point, where different portions of the visible spectrum are subject to different shadowing effects. These effects degrade the quality of the acquired optical data and can reduce the accuracy of several derived quantities, such as those obtained by applying bio-optical algorithms directly to the shadow-perturbed data. As a result, optical remote sensing calibration and validation studies can be impaired if shadowing artifacts are not fully accounted for. In this work, the general in-water shadowing problem is examined for a particular case study. Backward Monte Carlo (MC) radiative transfer computations- performed in a vertically stratified, horizontally inhomogeneous, and realistic ocean-atmosphere system are shown to accurately simulate the shadow-induced relative percent errors affecting the radiance and irradiance data profiles acquired close to an oceanographic tower. Multiparameter optical data processing has provided adequate representation of experimental uncertainties allowing consistent comparison with simulations. The more detailed simulations at the subsurface depth appear to be essentially equivalent to those obtained assuming a simplified ocean-atmosphere system, except in highly stratified waters. MC computations performed in the simplified system can be assumed, therefore, to accurately simulate the optical measurements conducted under more complex sampling conditions (i.e., within waters presenting moderate stratification at most). A previously reported correction scheme, based on the simplified MC simulations, and developed for subsurface shadow-removal processing of in-water optical data taken close to the investigated oceanographic tower, is then validated adequately under most experimental conditions. It appears feasible to generalize the present tower-specific approach to solve other optical sensor shadowing problems pertaining to differently shaped deployment platforms, and also including surrounding structures and instrument casings.

  14. Anomalous Effects in Air While Cooling Water

    Sardo, Rachel

    2008-01-01

    Water is a unique compound with many anomalies and properties not fully understood. Designing an experiment in the laboratory to study such anomalies, we set up a series of experiments where a tube was placed inside a sealed container with thermocouples attached to the outer surface of the tube and in the air adjacent to the tube. Alternately, deionized water and other compounds were added to the tube and cooled to freezing. Several of the thermocouples suspended in the air and adjacent to the tube showed thermal oscillations as the overall temperature of the container was decreasing. The temperature of the thermocouples increased and decreased in a sinusoidal way during part of the cool down to freezing. Thermal oscillations as large as 3 degrees Celsius were recorded with typical frequencies of about 5 oscillations per minute.

  15. Core cooling in pressurized-water reactor during water injection

    In this paper, the reactor core cooling and its melt progression terminating is evaluated, and the initiation criterion for reactor cavity flooding during water injection is determined. The core cooling in pressurized-water reactor of severe accident is simulated with the thermal hydraulic and severe accident code of SCDAP/RELAP5. The results show that the core melt progression is terminated by water injection, before the core debris has formed at bottom of core, and the initiation of reactor cavity flooding is indicated by the core exit temperature. (authors)

  16. Monitoring of LWR component cooling water systems

    As part of the Nuclear Plant Aging Research program, the monitoring methods used for component cooling water (CCW) systems in pressurized water reactors (PWRs) were reviewed and evaluated in terms of their effectiveness at detecting various aging mechanisms. A survey of PWRs was performed to determine what practices are currently used. Monitoring methods for three of the major components in the CCW system were correlated with the aging mechanisms they are able to detect, and generic tables of practices were developed. These tables can be used by utilities to strengthen their monitoring program once specific aging concerns have been identified. 1 ref., 2 figs., 5 tabs

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

    Jader D Alean

    2009-01-01

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

  18. 40 CFR 401.14 - Cooling water intake structures.

    2010-07-01

    ... AND STANDARDS GENERAL PROVISIONS § 401.14 Cooling water intake structures. The location, design, construction and capacity of cooling water intake structures of any point source for which a standard is... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Cooling water intake structures....

  19. Water Towers, City of Hutchinson Water Storage Facilities point file layer, Published in 2002, 1:600 (1in=50ft) scale, City of Hutchinson.

    NSGIC GIS Inventory (aka Ramona) — This Water Towers dataset, published at 1:600 (1in=50ft) scale, was produced all or in part from Orthoimagery information as of 2002. It is described as 'City of...

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

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

    1981-08-01

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

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

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

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

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

  3. Guidelines for effective oxidant use with cooling water corrosion inhibitors

    Robinette, D.; Puckorius, P.R. [Puckorius and Associates, Inc., Evergreen, CO (United States)

    1996-10-01

    Oxidants used in cooling water systems impact scale, corrosion, and biological inhibitors to various degrees. The various oxidants used in cooling systems, along with the various cooling water inhibitors, are reviewed relative to incompatibility. This paper is a compilation of known and experienced incidences when using biocide oxidants for cooling water system biological control. It is designed to alert users of potential concerns when using oxidants and to provide guidelines for their effective use of oxidants.

  4. Heat dissipation in water-cooled reflectors

    Kozai, Toyoki

    1994-01-01

    The energy balance of a lamp varies with the thermal and optical characteristics of the reflector. The photosynthetic radiation efficiency of lamps, defined as input power divided by photosynthetically active radiation (PAR, 400-700 nm) emitted from the lamp ranges between 0.17 and 0.26. The rest of the energy input is wasted as longwave (3000 nm and over) and non-PAR shortwave radiation (from 700 nm to 3000 nm), convective, and conductive heat from the lamp, reflector, and ballast, and simply for increasing the cooling load. Furthermore, some portion of the PAR is uselessly absorbed by the inner walls, shelves, vessels, etc. and some portion of the PAR received by the plantlets is converted into sensible and latent heat. More than 98% of the energy input is probably converted into heat, with only less than 2% of the energy input being converted into chemical energy as carbohydrates by photosynthesis. Therefore, it is essential to reduce the generation of heat in the culture room in order to reduce the cooling load. Through use of a water-cooled reflector, the generation of convective and conductive heat and longwave radiation from the reflector can be reduced, without reduction of PAR.

  5. WRI 50: Strategies for Cooling Electric Generating Facilities Utilizing Mine Water

    Joseph J. Donovan; Brenden Duffy; Bruce R. Leavitt; James Stiles; Tamara Vandivort; Paul Ziemkiewicz

    2004-11-01

    Power generation and water consumption are inextricably linked. Because of this relationship DOE/NETL has funded a competitive research and development initiative to address this relationship. This report is part of that initiative and is in response to DOE/NETL solicitation DE-PS26-03NT41719-0. Thermal electric power generation requires large volumes of water to cool spent steam at the end of the turbine cycle. The required volumes are such that new plant siting is increasingly dependent on the availability of cooling circuit water. Even in the eastern U.S., large rivers such as the Monongahela may no longer be able to support additional, large power stations due to subscription of flow to existing plants, industrial, municipal and navigational requirements. Earlier studies conducted by West Virginia University (WV 132, WV 173 phase I, WV 173 Phase II, WV 173 Phase III, and WV 173 Phase IV in review) have identified that a large potential water resource resides in flooded, abandoned coal mines in the Pittsburgh Coal Basin, and likely elsewhere in the region and nation. This study evaluates the technical and economic potential of the Pittsburgh Coal Basin water source to supply new power plants with cooling water. Two approaches for supplying new power plants were evaluated. Type A employs mine water in conventional, evaporative cooling towers. Type B utilizes earth-coupled cooling with flooded underground mines as the principal heat sink for the power plant reject heat load. Existing mine discharges in the Pittsburgh Coal Basin were evaluated for flow and water quality. Based on this analysis, eight sites were identified where mine water could supply cooling water to a power plant. Three of these sites were employed for pre-engineering design and cost analysis of a Type A water supply system, including mine water collection, treatment, and delivery. This method was also applied to a ''base case'' river-source power plant, for comparison. Mine-water system cost estimates were then compared to the base-case river source estimate. We found that the use of net-alkaline mine water would under current economic conditions be competitive with a river-source in a comparable-size water cooling system. On the other hand, utilization of net acidic water would be higher in operating cost than the river system by 12 percent. This does not account for any environmental benefits that would accrue due to the treatment of acid mine drainage, in many locations an existing public liability. We also found it likely that widespread adoption of mine-water utilization for power plant cooling will require resolution of potential liability and mine-water ownership issues. In summary, Type A mine-water utilization for power plant cooling is considered a strong option for meeting water needs of new plant in selected areas. Analysis of the thermal and water handling requirements for a 600 megawatt power plant indicated that Type B earth coupled cooling would not be feasible for a power plant of this size. It was determined that Type B cooling would be possible, under the right conditions, for power plants of 200 megawatts or less. Based on this finding the feasibility of a 200 megawatt facility was evaluated. A series of mines were identified where a Type B earth-coupled 200 megawatt power plant cooling system might be feasible. Two water handling scenarios were designed to distribute heated power-plant water throughout the mines. Costs were developed for two different pumping scenarios employing a once-through power-plant cooling circuit. Thermal and groundwater flow simulation models were used to simulate the effect of hot water injection into the mine under both pumping strategies and to calculate the return-water temperature over the design life of a plant. Based on these models, staged increases in required mine-water pumping rates are projected to be part of the design, due to gradual heating and loss of heat-sink efficiency of the rock sequence above the mines. Utilizing pumping strategy No.1 (two mines) capital costs were 25 percent lower and operating cost 19 percent higher than a conventional river-water cooling water scheme. Utilizing pumping strategy No.2 (three mines), capital costs were 20 percent lower and operating costs 192 percent higher. Major capital cost advantages are obtained by using earth-coupled cooling, due in large part to elimination of need for cooling towers. In addition, the lack of cooling towers and of thermal-pollution considerations may be positive factors in power plant permitting. However, application of Type B earth-coupled cooling will be technically feasible limited at a much smaller number of sites than Type A systems due to requirements involving mine size, geometry, and hydraulic conditions. Innovations such as directional drilling may be required to create mine interconnections across barriers where none presently exist.

  6. Reuso de efluentes em torres de resfriamento - estudo conceitual: Aeroporto Internacional do Rio de Janeiro - doi: 10.4025/actascitechnol.v32i3.865 Water reuse for cooling towers – conceptual study: Rio de Janeiro International Airport - doi: 10.4025/actascitechnol.v32i3.865

    Bernardo José Farah Machado

    2010-11-01

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

  7. Review of high temperature water and steam cooled reactor concepts

    This review summarizes design concepts of supercritical-pressure water cooled reactors (SCR), nuclear superheaters and steam cooled fast reactors from 1950's to the present time. It includes water moderated supercritical steam cooled reactor, SCOTT-R and SC-PWR of Westinghouse, heavy water moderated light water cooled SCR of GE, SCLWR and SCFR of the University of Tokyo, B-500SKDI of Kurchatov Institute, CANDU-X of AECL, nuclear superheaters of GE, subcritical-pressure steam cooled. FBR of KfK and B and W, Supercritical-pressure steam cooled FBR of B and W, subcritical-pressure steam cooled high converter by Edlund and Schultz and subcritical-pressure water-steam cooled FBR by Alekseev. (author)

  8. Chemical problems in the waste stripper tower of a heavy water plant

    An attempt has been made to understand the deposition problem encountered in the waste stripper tower of a heavy water plant based on the water-hydrogen sulphide exchange process. Brucite and chrysotile have been found to account for about 55% of the total amount of deposits with the rest being pyrite. Deposit characterisation when looked in conjunction with the plant's process feed water chemistry has thrown light on the cause for this deposition. Based on this analysis, a recommendation to use only deionised water as process feed water has been implemented in the plant. Computation on the speciation of H2S (a) at high temperature, pH 4-7 (which corresponds to the actual situation in the waste stripper), and (b) at ambient temperature, pH8-9(which corresponds to the situation when the effluent water gets mixed with lake water) have shown that HS- existing at the lower outlet has no chance of getting converted to H2S. (author). 13 refs., 5 tabs., 2 figs

  9. Cooling water facilities at a nuclear station

    The use of ponds for holding a reserve of cooling water obtained as sewage effluent and also for collection of waste water for disposal by evaporation, was made at a nuclear power plant site in southern Arizona. The power output of the plant will be 3,900 MW. Two single cell ponds are 80 acres (30 ha) and 250 acres (100 ha) in size. Excavated materials from the 80-acre (30ha) pond were used for structural backfill as planned, and the 250-acre (100ha) pond was designed for limited dike height with balanced cut and fill and some excess materials used as side berms for additional safety. Both ponds are being lined with a unique combination of linings to provide environmental safeguards and at the same time cost-effectiveness is compared to alternative schemes

  10. Electrochemistry of Water-Cooled Nuclear Reactors

    This project developed a comprehensive mathematical and simulation model for calculating thermal hydraulic, electrochemical, and corrosion parameters, viz. temperature, fluid flow velocity, pH, corrosion potential, hydrogen injection, oxygen contamination, stress corrosion cracking, crack growth rate, and other important quantities in the coolant circuits of water-cooled nuclear power plants, including both Boiling Water Reactors (BWRs) and Pressurized Water Reactors (PWRs). The model is being used to assess the three major operational problems in Pressurized Water Reactors (PWR), which include mass transport, activity transport, and the axial offset anomaly, and provide a powerful tool for predicting the accumulation of SCC damage in BWR primary coolant circuits as a function of operating history. Another achievement of the project is the development of a simulation tool to serve both as a training tool for plant operators and as an engineering test-bed to evaluate new equipment and operating strategies (normal operation, cold shut down and others). The development and implementation of the model allows us to estimate the activity transport or ''radiation fields'' around the primary loop and the vessel, as a function of the operating parameters and the water chemistry

  11. Caries selective ablation: effects of water cooling

    Hennig, Thomas; Rechmann, Peter; Abel, Martin

    1994-12-01

    The aim of the study was to describe the effects of different surrounding media -- water and air -- during application of a caries selective laser system on healthy dentin, the substance which should be preserved. Fluences used in this study were chosen with respect to the previously described ablation thresholds of healthy dentin. Fiber optics (0 400 micrometers , N.A. 0, 12) were used for transmission of the laser radiation. Luminescence emission was recorded time resolved in order to differentiate between fluorescence and plasma emission. Hot plasma seems to be rigorously reduced if the irradiation is performed under water. Scanning electron microscopical investigations were performed. Craters irradiated in air show cracks and signs of melting whereas crater walls after irradiation under water demonstrated rough surfaces and open dentinal tubules. Cracks did not occur if irradiation was performed in water. As long as water cooling is provided a Q-switched, frequency-doubled Alexandrite-laser providing fluences of 5 Jcm-2 at the tooth surface does not produce hot plasma during the ablation of healthy dentin.

  12. Electrochemistry of Water-Cooled Nuclear Reactors

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

    2006-08-08

    This project developed a comprehensive mathematical and simulation model for calculating thermal hydraulic, electrochemical, and corrosion parameters, viz. temperature, fluid flow velocity, pH, corrosion potential, hydrogen injection, oxygen contamination, stress corrosion cracking, crack growth rate, and other important quantities in the coolant circuits of water-cooled nuclear power plants, including both Boiling Water Reactors (BWRs) and Pressurized Water Reactors (PWRs). The model is being used to assess the three major operational problems in Pressurized Water Reactors (PWR), which include mass transport, activity transport, and the axial offset anomaly, and provide a powerful tool for predicting the accumulation of SCC damage in BWR primary coolant circuits as a function of operating history. Another achievement of the project is the development of a simulation tool to serve both as a training tool for plant operators and as an engineering test-bed to evaluate new equipment and operating strategies (normal operation, cold shut down and others). The development and implementation of the model allows us to estimate the activity transport or "radiation fields" around the primary loop and the vessel, as a function of the operating parameters and the water chemistry.

  13. Cooling-water amounts, temperature, and the environment

    The release of heat from power plants into a water can take place with relative small quantities of cooling water, highly warmed up accordingly, or with large quantities of cooling water slightly warmed up. The utilization of cooling water is bound to certain guidelines established by the authorities. With the intention to protect the environment, the admissable temperatures and warming-up have been strictly limited by the authorities. In the Netherlands, we have presently temporary cooling water guidelines which allow a max. temperature of the cooling water in the cooling cycle of 300C and a maximum admissible temperature rise in the condenser between 70C during summer and 150C during winter. It has also been determined in these requirements how much cooling water at least has to be used to discharge a specified quantity of heat. Plankton, spawn and young fish are dragged with the cooling water. Harm to these organisms can be caused mechanically by pumps, sieves and the condenser or they can be harmed by the temperature rise in the condenser. Investigations showed that mechanical harm to spawn and young fish in the cooling water flow should not be ignored, and that detectable harm to plankton organisms takes place only at water temperatures above 320C. The cooling water consumption can therefore be optimised as follows: The solution of a greater temperature increase and a slightly higher value for the temperature maximum can reduce the cooling water quantity. This reduction of the cooling water quantity reduces the destruction of the fish quantity, which gets into the cooling water system, especially during the summer. If the temperature rise and the temperature itself are not selected too high, the destruction of fish may be reduced without causing serious damage to the plankton. (orig.)

  14. An evaluation of fish behavior upstream of the water temperature control tower at Cougar Dam, Oregon, using acoustic cameras, 2013

    Adams, Noah S.; Smith, Collin; Plumb, John M.; Hansen, Gabriel S.; Beeman, John W.

    2015-01-01

    This report describes the initial year of a 2-year study to determine the feasibility of using acoustic cameras to monitor fish movements to help inform decisions about fish passage at Cougar Dam near Springfield, Oregon. Specifically, we used acoustic cameras to measure fish presence, travel speed, and direction adjacent to the water temperature control tower in the forebay of Cougar Dam during the spring (May, June, and July) and fall (September, October, and November) of 2013. Cougar Dam is a high-head flood-control dam, and the water temperature control tower enables depth-specific water withdrawals to facilitate adjustment of water temperatures released downstream of the dam. The acoustic cameras were positioned at the upstream entrance of the tower to monitor free-ranging subyearling and yearling-size juvenile Chinook salmon (Oncorhynchus tshawytscha). Because of the large size discrepancy, we could distinguish juvenile Chinook salmon from their predators, which enabled us to measure predators and prey in areas adjacent to the entrance of the tower. We used linear models to quantify and assess operational and environmental factorssuch as time of day, discharge, and water temperaturethat may influence juvenile Chinook salmon movements within the beam of the acoustic cameras. Although extensive milling behavior of fish near the structure may have masked directed movement of fish and added unpredictability to fish movement models, the acoustic-camera technology enabled us to ascertain the general behavior of discrete size classes of fish. Fish travel speed, direction of travel, and counts of fish moving toward the water temperature control tower primarily were influenced by the amount of water being discharged through the dam.

  15. Fast reactor cooled by supercritical light water

    Ishiwatari, Yuki; Mukouhara, Tami; Koshizuka, Seiichi; Oka, Yoshiaki [Tokyo Univ., Nuclear Engineering Research Lab., Tokai, Ibaraki (Japan)

    2001-09-01

    This report introduces the result of a feasibility study of a fast reactor cooled by supercritical light water (SCFR) with once-through cooling system. It is characterized by (1) no need of steam separator, recirculation system, or steam generator, (2) 1/7 of core flow rate compared with BWR or PWR, (3) high temperature and high pressure permits small turbine and high efficiency exceeding 44%, (4) structure and operation of major components are already experienced by LWRs or thermal power plants. Modification such as reducing blanket fuels and increasing seed fuels are made to achieve highly economic utilization of Pu and high power (2 GWe). The following restrictions were satisfied. (1) Maximum linear heat rate 39 kW/m, (2) Maximum surface temperature of Inconel cladding 620degC, (3) Negative void reactivity coefficient, (4) Fast neutron irradiation rate at the inner surface of pressure vessel less than 2.0x10{sup 19} n/cm{sup 2}. Thus the high power density of 167 MW/m{sup 3} including blanket is thought to contributes economy. The high conversion is attained to be 0.99 Pu fission residual rate by the outer radius of fuel rod of 0.88 mm. The breeding of 1.034 by Pu fission residual rate can be achieved by using briquette (tube-in-shell) type fuel structure. (K. Tsuchihashi)

  16. Technological readiness of evolutionary water cooled reactors

    Nuclear energy has evolved to a mature industry that supplies over 16% of the world's electricity, and it represents an important option for meeting the global energy demands of the coming century in an environmentally acceptable manner. New, evolutionary water cooled reactor designs that build on successful performance of predecessors have been developed; these designs have generally been guided by wishes to reduce cost, to improve availability and reliability, and to meet increasingly stringent safety objectives. These three aspects are important factors in what has been called technological readiness for an expanded deployment of nuclear power; a major increase in utilization of nuclear power will only occur if it is economically competitive, and meets safety expectations. To this end, the industry will also have to maintain or improve the public perception of nuclear power as a benign, economical and reliable energy source. (author)

  17. Deposit control in process cooling water systems

    In order to achieve efficient heat transfer in cooling water systems, it is essential to control the fouling of heat exchanger surfaces. Solubilities of scale forming salts, their growth into crystals, and the nature of the surfaces play important roles in the deposition phenomenon. Condensed phosphates, organic polymers and compounds like phosphates are effective in controlling deposition of scale forming salts. The surface active agents inhibit crystal growth and modify the crystals of the scale forming salts, and thus prevent deposition of dense, uniformly structured crystalline mass on the heat transfer surface. Understanding the mechanism of biofouling is essential to control it by surface active agents. Certain measures taken in the plant, such as back flushing, to control scaling, sometimes may not be effective and can be detrimental to the system itself. (author)

  18. Heavy water moderated gas-cooled reactors

    France has based its main effort for the production of nuclear energy on natural Uranium Graphite-moderated gas-cooled reactors, and has a long term programme for fast reactors, but this country is also engaged in the development of heavy water moderated gas-cooled reactors which appear to present the best middle term prospects. The economy of these reactors, as in the case of Graphite, arises from the use of natural or very slightly enriched Uranium; heavy water can take the best advantages of this fuel cycle and moreover offers considerable development potential because of better reactor performances. A prototype plant EL 4 (70 MW) is under construction and is described in detail in another paper. The present one deals with the programme devoted to the development of this reactor type in France. Reasons for selecting this reactor type are given in the first part: advantages and difficulties are underlined. After reviewing the main technological problems and the Research and Development carried out, results already obtained and points still to be confirmed are reported. The construction of EL 4 is an important step of this programme: it will be a significant demonstration of reactor performances and will afford many experimentation opportunities. Now the design of large power reactors is to be considered. Extension and improvements of the mechanical structures used for EL 4 are under study, as well as alternative concepts. The paper gives some data for a large reactor in the present state of technology, as a result from optimization studies. Technical improvements, especially in the field of materials could lead to even more interesting performances. Some prospects are mentioned for the long run. Investment costs and fuel cycles are discussed in the last part. (authors)

  19. Condenser tube failures in water-cooled condensers with copper-based alloys

    Bursik, A. [PowerPlant Chemistry GmbH, Neulussheim (Germany); Seipp, H.G.

    2007-09-15

    Integrity of the condenser is one of the most important prerequisites for optimum availability, reliability and performance of fossil and nuclear units. For many decades, copper-based alloys exclusively were used for condenser tubing. Recently, generic 300 Series stainless steels, proprietary austenitic and ferritic stainless steels, and titanium seem to have completely displaced the traditional copper-based alloys. However, arsenical admiralty brass, arsenical aluminum brass, and 70-30 copper-nickel alloy have been successfully applied in countless applications in units with once-through and circulating cooling tower systems. It is believed that also in the future copper-based alloys will maintain their important position among the condenser tube materials. This contribution focuses on operation experience and the most important types of tube failures in water-cooled condensers with copper-based alloys. (orig.)

  20. Surface studies of corrosion inhibitors in cooling water systems

    This paper reports electron spectroscopy for chemical analysis combined with argon-ion sputtering, used to obtain the thickness and composition profile of a mild steel tube from a dynamic simulation test (i.e., pilot cooling tower) of a stabilized phosphate program. The surface layer was found to be 3500 A thick, and contained carbon, phosphorus, calcium, iron, and oxygen. The relative amounts and chemical state of the elements were found to vary with the thickness of the film. The interface between the film and the mild steel tube was found to be predominantly FeOOH, with a small amount of FePO4

  1. Advanced cooling technologies

    Power plant cooling is the major use of water at nearly all thermo-electric generating plants. The withdrawal, consumption and discharge of water for power production raises some of the most contentious siting issues for new plants. This paper will review the major cooling system types and discuss the advantages and disadvantages of each from both the cost/performance and environmental effects viewpoints. Historically, the preferred cooling system for large plants was once-through cooling. In the past few decades, the trend has been to closed-cycle wet cooling to reduce the environmental effects of heated water discharges and large withdrawal rates. More recently, the use of dry and hybrid cooling has been chosen at many sites. The application of dry and hybrid cooling to nuclear plants can introduce design problems not encountered in fossil plants and may lead to the consideration of indirect dry cooling and the reintroduction of natural draft cooling towers. In addition, a number of emerging technologies such as the recovery of water from the plumes of wet cooling towers, the use of inlet air sprays to enhance the performance of dry systems and some innovative approaches to the use of alternative (non-fresh) water supplies may find application in the near future. Some possible research directions for future cooling system improvements are considered. (authors)

  2. WGOTHIC analysis of AP1000 passive containment cooling water

    The WGOTHIC code was used to analyze the influence of the containment cooling water inventory to containment safety for different cases. The results show that if passive containment cooling system fails, the pressure in containment is beyond design limit after 1000 s; if cooling water can't be supplied after 72 h, the pressure in containment is beyond design limit after 0.9 d; if cooling water can't be supplied after 19.6 d, the pressure in containment is beyond design limit but less than the breakdown pressure; if cooling water is supplied for 30 d, the air cooling can remove the decay heat without any aid. It is a reference for making emergency plan and improving containment design. (authors)

  3. Storage of HLW in engineered structures: air-cooled and water-cooled concepts

    A comparative study on an air-cooled and a water-cooled intermediate storage of vitrified, highly radioactive waste (HLW) in overground installations has been performed by Nukem and Belgonucleaire respectively. In the air-cooled storage concept the decay heat from the storage area will be removed using natural convection. In the water-cooled storage concept the decay heat is carried off by a primary and secondary forced-cooling system with redundant and diverse devices. The safety study carried out by Nukem used a fault tree method. It shows that the reliability of the designed water-cooled system is very high and comparable to the inherent, safe, air-cooled system. The impact for both concepts on the environment is determined by the release route, but even during accident conditions the release is far below permissible limits. The economic analysis carried out by Belgonucleaire shows that the construction costs for both systems do not differ very much, but the operation and maintenance costs for the water-cooled facility are higher than for the air cooled facility. The result of the safety and economic analysis and the discussions with the members of the working group have shown some possible significant modifications for both systems, which are included in this report. The whole study has been carried out using certain national criteria which, in certain Member States at least, would lead to a higher standard of safety than can be justified on any social, political or economic grounds

  4. Assessing MODIS GPP in Non-Forested Biomes in Water Limited Areas Using EC Tower Data

    Flor lvarez-Taboada

    2015-03-01

    Full Text Available Although shrublands, savannas and grasslands account for 37% of the worlds terrestrial area, not many studies have analysed the role of these ecosystems in the global carbon cycle at a regional scale. The MODIS Gross Primary Production (GPP product is used here to help bridge this gap. In this study, the agreement between the MODIS GPP product (GPPm and the GPP Eddy Covariance tower data (GPPec was tested for six different sites in temperate and dry climatic regions (three grasslands, two shrublands and one evergreen forest. Results of this study show that for the non-forest sites in water-limited areas, GPPm is well correlated with GPPec at annual scales (r2 = 0.77, n = 12; SEE = 149.26 g C?m?2?year?1, although it tends to overestimate GPP and it is less accurate in the sites with permanent water restrictions. The use of biome-specific models based on precipitation measurements at a finer spatial resolution than the Data Assimilation Office (DAO values can increase the accuracy of these estimations. The seasonal dynamics and the beginning and end of the growing season were well captured by GPPm for the sites where (i the productivity was low throughout the year or (ii the changes in the flux trend were abrupt, usually due to the restrictions in water availability. The agreement between GPPec and GPPm in non-forested sites was lower on a weekly basis than at an annual scale (0.44 ? r2 ? 0.49, but these results were improved by including meteorological data at a finer spatial scale, and soil water content and temperature measurements in the model developed to predict GPPec (0.52 ? r2 ? 0.65.

  5. Operating manual for the Tower Shielding Facility

    This manual provides information necessary to operate and perform maintenance on the reactor systems and all equipment or systems which can affect their operation or the safety of personnel at the Tower Shielding Facility. The first four chapters consist of introductory and descriptive material of benefit to personnel in training, the qualifications required for training, the responsibilities of the personnel in the organization, and the procedures for reviewing proposed experiments. Chapter 8, Emergency Procedures, is also a necessary part of the indoctrination of personnel. The procedures for operation of the Tower Shielding Reactor (TSR-II), its water cooling system, and the main tower hoists are outlined in Chapters 5, 6, and 7. The Technical Specification surveillance requirements for the TSR-II are summarized in Chapter 9. The maintenance and calibration schedule is spelled out in Chapter 10. The procedures for assembly and disassembly of the TSR-II are outlined in Chapter 11

  6. Technical analysis of a river basin-based model of advanced power plant cooling technologies for mitigating water management challenges

    Thermoelectric power plants require large volumes of water for cooling, which can introduce drought vulnerability and compete with other water needs. Alternative cooling technologies, such as cooling towers and hybrid wet-dry or dry cooling, present opportunities to reduce water diversions. This case study uses a custom, geographically resolved river basin-based model for eleven river basins in the state of Texas (the Brazos and San Jacinto-Brazos, Colorado and Colorado-Brazos, Cypress, Neches, Nueces, Red, Sabine, San Jacinto, and Trinity River basins), focusing on the Brazos River basin, to analyze water availability during drought. We utilized two existing water availability models for our analysis: (1) the full execution of water rights-a scenario where each water rights holder diverts the full permitted volume with zero return flow, and (2) current conditions-a scenario reflecting actual diversions with associated return flows. Our model results show that switching the cooling technologies at power plants in the eleven analyzed river basins to less water-intensive alternative designs can potentially reduce annual water diversions by 247-703 million m3-enough water for 1.3-3.6 million people annually. We consider these results in a geographic context using geographic information system tools and then analyze volume reliability, which is a policymaker's metric that indicates the percentage of total demand actually supplied over a given period. This geographic and volume reliability analysis serves as a measure of drought susceptibility in response to changes in thermoelectric cooling technologies. While these water diversion savings do not alleviate all reliability concerns, the additional streamflow from the use of dry cooling alleviates drought concerns for some municipal water rights holders and might also be sufficient to uphold instream flow requirements for important bays and estuaries on the Texas Gulf coast.

  7. Validation of the kinetic model for predicting the composition of chlorinated water discharged from power plant cooling systems

    The purpose of this report is to present a validation of a previously described kinetic model which was developed to predict the composition of chlorinated fresh water discharged from power plant cooling systems. The model was programmed in two versions: as a stand-alone program and as a part of a unified transport model developed from consistent mathematical models to simulate the dispersion of heated water and radioisotopic and chemical effluents from power plant discharges. The results of testing the model using analytical data taken during operation of the once-through cooling system of the Quad Cities Nuclear Station are described. Calculations are also presented on the Three Mile Island Nuclear Station which uses cooling towers

  8. Investigation of statistical behavior of nuclear power plant reinforced concrete cooling tower shell due to randomness in material and geometrical parameters using simulation approach

    In this paper, the response variability of reinforced concrete cooling tower shell due to randomness in material and geometrical parameters is investigated based on the simulation approach by using Monte Carlo simulation. Contrary to the ideal assumption on the shape imperfection such as the axisymmetric cosine shape and/or the cyclic shape imperfections we assume the shape imperfection due to randomness in the geometrical parameters as stochastic field and consider also the material randomness in the elastic modulus of concrete. By assuming correlation between these random parameters, the effect of randomness of these parameters on the response variability is investigated. Based on the analysis on the numerical results, a detailed investigation on the statistical response is given. In particular, the effect of correlation on the response variability in between the random parameters is addressed with which the analysis and design procedures of this structure can be improved. (authors)

  9. Treating cooling pond water for Wabamun Lake level mitigation project in Alberta

    Dealing with the challenge of recharging Wabamun Lake by treating nearby cooling pond water, fed by the North Saskatchewan River, and returning it to the lake, is discussed. To deal with the problem, TransAlta Utilities constructed a treatment plant in 1997 next to the 2,029 MW Sundance power plant to mitigate the effect the power plant's ongoing and historical effect on the lake's water level. The objective of the treatment plant is to treat cooling pond water and return it to the lake to raise water levels there, which have been significantly reduced over the last 25 years mostly by power plant intake, but also by lack of rainfall, surface runoff, and natural evaporation. At the Treatment Facility the water to be treated is first chlorinated to kill zooplankton, algae and bacteria, followed by adjusting the pH using sulfuric acid. Alum coagulant is used to destabilize colour, particles and colloids. The next step is feeding the water to the Actiflo clarifiers which use microsand to provide increased surface area for floc attachment, and to act as ballast. Clarified water from the Actiflo system is then fed to to the Dusenflo filters to remove the largest particles of suspended solids, and through a finer sand media to remove the remaining turbidity, colour and bacteria. Thiosulfate is used in the ozonation system to inactivate any remaining bacteria and zooplankton in the filtered water, before discharging it to the lake. The cooling towers, which are part of the system, ensure that the treated water returned to the lake is kept at a constant temperature, varying no more than three degrees C from the lake water temperature. 3 figs

  10. Water cooled reactor technology: Safety research abstracts no. 1

    The Commission of the European Communities, the International Atomic Energy Agency and the Nuclear Energy Agency of the OECD publish these Nuclear Safety Research Abstracts within the framework of their efforts to enhance the safety of nuclear power plants and to promote the exchange of research information. The abstracts are of nuclear safety related research projects for: pressurized light water cooled and moderated reactors (PWRs); boiling light water cooled and moderated reactors (BWRs); light water cooled and graphite moderated reactors (LWGRs); pressurized heavy water cooled and moderated reactors (PHWRs); gas cooled graphite moderated reactors (GCRs). Abstracts of nuclear safety research projects for fast breeder reactors are published independently by the Nuclear Energy Agency of the OECD and are not included in this joint publication. The intention of the collaborating international organizations is to publish such a document biannually. Work has been undertaken to develop a common computerized system with on-line access to the stored information

  11. Monitoring and disinfection of biofilm-associated sulfate reducing bacteria on different substrata in a simulated recirculating cooling tower system

    SUNGUR, Esra İLHAN; TÜRETGEN, İrfan; Javaherdashti, Reza; Çotuk, Ayşın

    2010-01-01

    Microbial biofilm and corrosion in cooling systems are the most common problems that damage expensive equipment, cause loss of production, and increase maintenance costs. Sulfate reducing bacteria were considered the major bacterial group involved in microbiologically influenced corrosion (MIC). We investigated the survival and enumeration of biofilm-associated SRB on coupons of galvanized steel, stainless steel, and copper, which are materials used in the manufacturing of cooling systems. We...

  12. USE OF PRODUCED WATER IN RECIRCULATING COOLING SYSTEMS AT POWER GENERATING FACILITIES

    Michael N. DiFilippo

    2004-08-01

    The purpose of this study is to evaluate produced water as a supplemental source of water for the San Juan Generating Station (SJGS). This study incorporates elements that identify produced water volume and quality, infrastructure to deliver it to SJGS, treatment requirements to use it at the plant, delivery and treatment economics, etc. SJGS, which is operated by Public Service of New Mexico (PNM) is located about 15 miles northwest of Farmington, New Mexico. It has four units with a total generating capacity of about 1,800 MW. The plant uses 22,400 acre-feet of water per year from the San Juan River with most of its demand resulting from cooling tower make-up. The plant is a zero liquid discharge facility and, as such, is well practiced in efficient water use and reuse. For the past few years, New Mexico has been suffering from a severe drought. Climate researchers are predicting the return of very dry weather over the next 30 to 40 years. Concern over the drought has spurred interest in evaluating the use of otherwise unusable saline waters. Deliverable 1 presents a general assessment of produced water generation in the San Juan Basin in Four Corners Area of New Mexico. Oil and gas production, produced water handling and disposal, and produced water quantities and chemistry are discussed. Legislative efforts to enable the use of this water at SJGS are also described.

  13. ASSESSMENT OF WATER QUALITY PARAMETERS OF THE TASHLYK COOLING POOL

    Tamara V. Dudar

    2008-02-01

    Full Text Available Data on hydrochemical monitoring parameters and water quality for the South-Ukrainian Nuclear Power Plant cooling pool are considered in the paper. Changes in the Tashlyk cooling pool water physical and chemical parameters under influence of the South-Ukrainian Power Complex are analyzed. It was shown that values of some parameters exceed limited acceptable concentrations for water reservoir for fish economy.

  14. Temperature profile and water depth data collected from TOWERS in the NE Atlantic (limit-180 W) from 06 June 1986 to 29 August 1986 (NODC Accession 8600378)

    National Oceanic and Atmospheric Administration, Department of Commerce Temperature profile and water depth data were collected using BT and XBT from the TOWERS in the Northeast Atlantic Ocean, South China Sea, Philippine Sea, and...

  15. Increasing effectiveness of evaporative cooling by pre-cooling using nocturnally stored water

    In this paper, a multi-step system of nocturnal radiative cooling and two-stage evaporative cooling is studied. The feasibility and potential of this system is investigated for four cities which have different climatic conditions. During the night time in summer, water is circulated from a storage tank to two radiative panels. The temperature of the water from the radiative panels decreases because of radiative heat transfer between the water in panels and night sky. During the next day, the stored cold water in the storage tank is used as coolant for a cooling coil unit. Hot outdoor air is passed through the cooling coil unit and a two-stage evaporative cooler. The results obtained demonstrate that first, the multi-step system can be considered as an alternative cooling system in some hot regions that evaporative cooling cannot be used. Second, the multi-step system has higher effectiveness than conventional two-stage evaporative coolers. Third, an energy saving of the multi-step system is between 75 and 79% compared to mechanical vapor compression systems. Consequently, this environmentally-friendly and highly-efficient system can replace the mechanical vapor compression systems. - Highlights: ? The multi-step system meets the comfort conditions in various weather conditions. ? Adding nocturnal cooling to IDEC increases the effectiveness by 9%. ? The new system expands coverage of IDEC over hot and humid weather conditions. ? The energy efficiency ratio of the multi-step system is higher than 48.8.

  16. Corrosion of carbon steel in the stagnant cooling water

    In the cooling water system treated with zinc-polyphosphate inhibitor, the relationship between inhibitor performance and corroded conditions of heat exchangers was studied. When cooling water system was kept in wet lay-up state, inhibitor concentration in the water jucket of heat exchangers decreased 15 ? 30 percent per week, and turbidity increased 30 ? 150 percent per week. These results show that corrosion rate of shell-plate in stagnant cooling water is more rapid than in flowing cooling water. Applied trouble discrimination method based on SiO2 ratio to the chemical composition of corrosion products, corrosion trouble was observed in shell-plates of heat exchangers. When cooling water system is kept in wet lay-up state, cooling water in the water jucket of heat exchangers is isolated for mouter system. In this perfectly closed system, zinc-polyphosphate inhibitor was not effective for protection of corrosion of carbon steel, and metal (carbon steel) dissolution occurred. However, in the perfectly closed system, since the dissolved oxygen content of the system was reduced with lapse of time, reduction process at cathodic region was stopped, so corrosion of metals seemed to be inhibited. (author)

  17. Technology for Water Treatment (National Water Management)

    1992-01-01

    The buildup of scale and corrosion is the most costly maintenance problem in cooling tower operation. Jet Propulsion Laboratory successfully developed a non-chemical system that not only curbed scale and corrosion, but also offered advantages in water conservation, cost savings and the elimination of toxic chemical discharge. In the system, ozone is produced by an on-site generator and introduced to the cooling tower water. Organic impurities are oxidized, and the dissolved ozone removes bacteria and scale. National Water Management, a NASA licensee, has installed its ozone advantage systems at some 200 cooling towers. Customers have saved money and eliminated chemical storage and discharge.

  18. Use of Produced Water in Recirculated Cooling Systems at Power Generating Facilities

    C. McGowin; M. DiFilippo; L. Weintraub

    2006-06-30

    Tree ring studies indicate that, for the greater part of the last three decades, New Mexico has been relatively 'wet' compared to the long-term historical norm. However, during the last several years, New Mexico has experienced a severe drought. Some researchers are predicting a return of very dry weather over the next 30 to 40 years. Concern over the drought has spurred interest in evaluating the use of otherwise unusable saline waters to supplement current fresh water supplies for power plant operation and cooling and other uses. The U.S. Department of Energy's National Energy Technology Laboratory sponsored three related assessments of water supplies in the San Juan Basin area of the four-corner intersection of Utah, Colorado, Arizona, and New Mexico. These were (1) an assessment of using water produced with oil and gas as a supplemental supply for the San Juan Generating Station (SJGS); (2) a field evaluation of the wet-surface air cooling (WSAC) system at SJGS; and (3) the development of a ZeroNet systems analysis module and an application of the Watershed Risk Management Framework (WARMF) to evaluate a range of water shortage management plans. The study of the possible use of produced water at SJGS showed that produce water must be treated to justify its use in any reasonable quantity at SJGS. The study identified produced water volume and quality, the infrastructure needed to deliver it to SJGS, treatment requirements, and delivery and treatment economics. A number of produced water treatment alternatives that use off-the-shelf technology were evaluated along with the equipment needed for water treatment at SJGS. Wet surface air-cooling (WSAC) technology was tested at the San Juan Generating Station (SJGS) to determine its capacity to cool power plant circulating water using degraded water. WSAC is a commercial cooling technology and has been used for many years to cool and/or condense process fluids. The purpose of the pilot test was to determine if WSAC technology could cool process water at cycles of concentration considered highly scale forming for mechanical draft cooling towers. At the completion of testing, there was no visible scale on the heat transfer surfaces and cooling was sustained throughout the test period. The application of the WARMF decision framework to the San Juan Basis showed that drought and increased temperature impact water availability for all sectors (agriculture, energy, municipal, industry) and lead to critical shortages. WARMF-ZeroNet, as part of the integrated ZeroNet decision support system, offers stakeholders an integrated approach to long-term water management that balances competing needs of existing water users and economic growth under the constraints of limited supply and potential climate change.

  19. Utilizing the heat to thermal power plant cooling water

    Mann, E.W.

    1982-08-01

    The use of cooling water heat will open up new perspectives for plant cultivation and fish breeding (Agrotherm, Hortitherm, Limnotherm). Economic utilization can only be realized in close proximity to corresponding production units.

  20. Utilizing the heat ot thermal power plant cooling water

    The use of cooling water heat will open up new perspectives for plant cultivation and fish breeding (Agrotherm, Hortitherm, Limnotherm). Economic utilization can only be realized in close proximity to corresponding production units. (orig./HP)

  1. The influence of Savannah River discharge and changing SRS cooling water requirements on the potential entrainment of ichthyoplankton at the SRS Savannah River intakes

    Entrainment (i.e., withdrawal of fish larvae and eggs in cooling water) at the SRS Savannah River intakes is greatest when periods of high river water usage coincide with low river dischargeduring the spawning season. American shad and striped bass are the two species of greatest concern because of their recreational and/or commercial importance and because they produce drifting eggs and larvae vulnerable to entrainment. In the mid-reaches of the Savannah River, American shad and striped bass spawn primarily during April and May. An analysis of Savannah River discharge during April and May 1973--1989 indicated the potential for entrainment of 4--18% of the American shad and striped bass larvae and eggs that drifted past the SRS. This analysis assumed the concurrent operation of L-, K-, and P-Reactors. Additional scenarios investigated were: (1) shutting down L- and P-Reactors, and operating K-Reactor with a recycle cooling tower; and (2) shutting down L- and P-Reactors, eliminating minimum flows to Steel Creek, and operating K-Reactor with a recycle cooling tower. The former scenario reduced potential entrainment to 0.7--3.3%, and the latter scenario reduced potential entrainment to 0.20.8%. Thus, the currently favored scenario of operating K-Reactor with a cooling tower and not operating L- and P-Reactors represents a significant lessening of the impact of SRS operations

  2. DUSEL Facility Cooling Water Scaling Issues

    Daily, W D

    2011-04-05

    Precipitation (crystal growth) in supersaturated solutions is governed by both kenetic and thermodynamic processes. This is an important and evolving field of research, especially for the petroleum industry. There are several types of precipitates including sulfate compounds (ie. barium sulfate) and calcium compounds (ie. calcium carbonate). The chemical makeup of the mine water has relatively large concentrations of sulfate as compared to calcium, so we may expect that sulfate type reactions. The kinetics of calcium sulfate dihydrate (CaSO4 {center_dot} 2H20, gypsum) scale formation on heat exchanger surfaces from aqueous solutions has been studied by a highly reproducible technique. It has been found that gypsum scale formation takes place directly on the surface of the heat exchanger without any bulk or spontaneous precipitation in the reaction cell. The kinetic data also indicate that the rate of scale formation is a function of surface area and the metallurgy of the heat exchanger. As we don't have detailed information about the heat exchanger, we can only infer that this will be an issue for us. Supersaturations of various compounds are affected differently by temperature, pressure and pH. Pressure has only a slight affect on the solubility, whereas temperature is a much more sensitive parameter (Figure 1). The affect of temperature is reversed for calcium carbonate and barium sulfate solubilities. As temperature increases, barium sulfate solubility concentrations increase and scaling decreases. For calcium carbonate, the scaling tendencies increase with increasing temperature. This is all relative, as the temperatures and pressures of the referenced experiments range from 122 to 356 F. Their pressures range from 200 to 4000 psi. Because the cooling water system isn't likely to see pressures above 200 psi, it's unclear if this pressure/scaling relationship will be significant or even apparent. The most common scale minerals found in the oilfield include calcium carbonates (CaCO3, mainly calcite) and alkaline-earth metal sulfates (barite BaSO4, celestite SrSO4, anhydrite CaSO4, hemihydrate CaSO4 1/2H2O, and gypsum CaSO4 2H2O or calcium sulfate). The cause of scaling can be difficult to identify in real oil and gas wells. However, pressure and temperature changes during the flow of fluids are primary reasons for the formation of carbonate scales, because the escape of CO2 and/or H2S gases out of the brine solution, as pressure is lowered, tends to elevate the pH of the brine and result in super-saturation with respect to carbonates. Concerning sulfate scales, the common cause is commingling of different sources of brines either due to breakthrough of injected incompatible waters or mixing of two different brines from different zones of the reservoir formation. A decrease in temperature tends to cause barite to precipitate, opposite of calcite. In addition, pressure drops tend to cause all scale minerals to precipitate due to the pressure dependence of the solubility product. And we can expect that there will be a pressure drop across the heat exchanger. Weather or not this will be offset by the rise in pressure remains to be seen. It's typically left to field testing to prove out. Progress has been made toward the control and treatment of the scale deposits, although most of the reaction mechanisms are still not well understood. Often the most efficient and economic treatment for scale formation is to apply threshold chemical inhibitors. Threshold scale inhibitors are like catalysts and have inhibition efficiency at very low concentrations (commonly less than a few mg/L), far below the stoichiometric concentrations of the crystal lattice ions in solution. There are many chemical classes of inhibitors and even more brands on the market. Based on the water chemistry it is anticipated that there is a high likelihood for sulfate compound precipitation and scaling. This may be dependent on the temperature and pressure, which vary throughout the system. Therefore, various types and amounts of scaling may occur at different locations. Although it has been shown that decreased pressure causes increased scaling, it is unclear if this condition will have significant affect, as all the pressures are low. Sulfate concentrations predominate, but there is still a chance for calcium carbonate buildup, especially in the heat exchanger where the temperatures are rising. Additional information is needed to conduct a thorough analysis, but it would appear that a fairly simple injection system would be sufficient to address scaling issues.

  3. Upgrade of the cooling water temperature measures system for HLS

    The cooling water temperature measures system for HLS (Hefei Light Source) adopts EPICS to the developing platform and takes the intelligence temperature cruise instrument for the front control instrument. Data of temperatures are required by IOCs through Serial Port Communication, archived and searched by Channel Archiver. The system can monitor the real-time temperatures of many channels cooling water and has the function of history data storage, and data network search. (authors)

  4. Heat transfer during cooling of hot surfaces by water nozzles

    Příhoda, Miroslav; Molínek, Jiří; Pyszko, René; Velička, Marek; Vaculík, Miroslav; Burda, Jiří

    2009-01-01

    Method of cooling in a secondary zone of continuous casting of steel has a significant influence on a quality of continuously cast products mainly from the point of view of internal and surface defects as well as zonal segregations. At the department of thermal engineering, a physical model of the secondary zone has been developed, which enables testing of both water and water-air nozzles. During laboratory measurements cooling effects of a cone nozzle have been expressed by means...

  5. Cooling performance of helium-gas/water coolers in HENDEL

    The helium engineering demonstration loop (HENDEL) has four helium-gas/water coolers where the cooling water flows in the tubes and helium gas on the shell side. Their cooling performance was studied using the operational data from 1982 to 1991. The heat transfer of helium gas on the shell was obtained for segmental and step-up baffle type coolers. Also, the change with operation time was investigated. The cooling performance was lowered by the graphite powder released from the graphite components for several thousand hours and thereafter recovered because the graphite powder from the components was reduced and the powder in the cooler shell was blown off during the operation. (orig.)

  6. Evaluation of cooling water treatment programme at RAPS-3 and 4 with reference to chlorination and microbial control

    Water from Rana Pratap Sagar Lake is used in Rajasthan Atomic Power Station (RAPS) units 3 and 4 for cooling the condenser system. As the lake water is rich in nutrients and microflora, investigations were carried out on the nutrient quality, microflora distribution and chlorine decay to evaluate the cooling water treatment programme. Algal growth in emergency storage makeup water pools, weed growth on the cooling tower decks and biofilm growth on various materials (carbon steel, stainless steel, admiralty brass and cupronickel) were studied with an objective to understand the reasons for corrosion and failure of fire water pipeline. Visual examination showed that the emergency makeup water pools were infested with green algae and cyano-bacterial mats. Some algal growth was observed on induced draft cooling tower-3 structures. The bacterial counts in various water samples were low, except in emergency makeup water pool. Sulphate reducing bacteria (SRB) were present in makeup and demineralised waters. Chlorophyll pigment analysis showed that the makeup and emergency storage water pool had abundant algal growth. To prevent biofouling, chlorine is dosed at the rate of 7 kg/hr for 10 minutes; free residual oxidant (FRO) and chlorine decay were monitored at regular intervals. After 24 hrs, biofilm thickness on different materials ranged from 27-45 μm. However, the thickness was reduced by 50 % after exposure to 2 ppm of chlorine for 15 minutes. In further investigations, it was found that the anion resin beads of demineraliser plant were infested with filamentous microbes. Hence, It is recommended to treat the feed water of DM plant. Tubercles were observed inside the failed fire water carbon steel pipeline and on removing the tubercles concentric ring patterns, typical signatures of SRB corrosion were observed. For controlling the biofouling problem in the cooling water system, it is recommended to maintain a chlorine dose of 2.3 ppm (which gives 0.8 ppm FRO) for two hours in every shift. To control the algal growth in the emergency storage water pools, it is recommended to dose 4.0 ppm of sodium hypochlorite on alternate days. (author)

  7. Desiccant Dewpoint Cooling System Independent of External Water Sources

    Bellemo, Lorenzo; Elmegaard, Brian; Markussen, Wiebke B.; Kærn, Martin R.; Reinholdt, Lars O.

    2015-01-01

    This paper presents a patent pending technical solution aiming to make desiccant cooling systems independent of external water sources, hence solving problems of water availability, cost and treatment that can decrease the system attractiveness. The solution consists in condensing water from the...... desiccant dew-point cooling system, for demonstrating its function and applicability. Simulations are carried out for varying outdoor conditions under constant supply conditions. The results show that the system is independent of external water supply for the majority of simulated conditions. In comparison...

  8. Water cooling system for sintering furnaces of nuclear fuel pellets

    This work has as a main objective to develop a continuous cooling water system, which is necessary for the cooling of the sintering furnaces. This system is used to protect them as well as for reducing the water consumption, ejecting the heat generated into this furnaces and scattering it into the atmosphere in a fast and continuous way. The problem was defined and the reference parameters established, making the adequate research. The materials were selected as well as the length of the pipeline which will carry the secondary refrigerant fluid (water). Three possible solutions were tried,and evaluated, and from these, the thermal and economically most efficient option was selected. The layout of the solution was established and the theoretical construction of a cooling system for liquids using dichlorofluoromethane (R-22), as a refrigerant and a air cooled condenser, was accomplished. (Author)

  9. Device for removing after-heat and/or for emergency cooling of a water-cooled nuclear reactor

    A device for removing after-heat and/or for the emergency cooling of a water-cooled nuclear reactor should prevent the after-cooling pipe carrying the primary coolant from taking contamination outside the safety containment vessel. For this reason the after-cooling pipe including the allocated after-cooling pump and the heat exchanger are situated inside the safety containment vessel. The turbine and the heat exchanger are connected to an emergency cooling pipe, which can be switched over for the emergency cooling of the reactor core. The water flowing in the emergency cooling pipe drives the after-cooling pump via the turbine. After leaving the turbine, the water flows through the heat exchanger and thus gives up the heat of the medium flowing in the after-cooling pipe. (orig.)

  10. Water-lithium bromide double-effect absorption cooling analysis

    Vliet, G. C.; Lawson, M. B.; Lithgow, R. A.

    1980-12-01

    A numerical model was developed for the transient simulation of the double-effect, water-lithium bromide absorption cooling machine and was used to determine the effect of the various design and input variables on the absorption unit performance. The performance parameters considered were coefficient of performance and cooling capacity. The variables considered include source hot water, cooling water, and chilled water temperatures; source hot water, cooling water, and chilled water flow rates; solution circulation rate; heat exchanger areas; pressure drop between evaporator and absorber; solution pump characteristics; and refrigerant flow control methods. The performance sensitivity study indicates that the distribution of heat exchanger area among the various (seven) heat exchange components is a very important design consideration. Moreover, it indicated that the method of flow control of the first effect refrigerant vapor through the second effect is a critical design feature when absorption units operate over a significant range of cooling capacity. The model was used to predict the performance of the Trane absorption unit with fairly good accuracy.

  11. Cooling water conditioning and quality control for tokamaks

    Designers and operators of Tokamaks and all associated water cooled, peripheral equipment, are faced with the task of providing and maintaining closed-loop, low conductivity, low impurity, cooling water systems. Most of these systems must provide large volumes of high quality cooling water at reasonable cost and comply with local and state government orders and EPA mandated national pretreatment standards and regulations. This paper discusses the DIII-D water quality requirements, the means used to obtain the necessary quality and the instrumentation used for control and monitoring. Costs to mechanically and chemically condition and maintain water quality are discussed as well as the various aspects of complying with government standards and regulations

  12. Experimental and numerical study of water-cooled datacom equipment

    This paper presents an experimental and numerical study of an electronic rack cooled by a finned tube heat exchanger. The objectives are to evaluate cooling and energy performance of this system and formulate a numerical model based on measurements. Experimentation has been carried out using commercial servers. A substantial instrumentation has been conducted at different scales (servers, rack and exchanger). Several tests have been made with different sets of parameters like water inlet temperature or power dissipated by servers. In each case, the heat exchanger has removed more than 90% of electrical power consumed by the rack (with no chiller use). Furthermore, promising results are obtained with this system, especially the reduction of energy consumption of cooling part compared to traditional air cooling. Finally, the rack and heat exchanger are simplified into two numerical models which can predict temperature outputs as a function of defined inputs (water and air flow rate and temperature, power dissipation). Validation tests have been carried out with different sequences of measure and numerical models have given satisfactory results. They will be duplicated to compute the impact of this cooling system at a data center room scale. - Highlights: • A study of an electronic rack cooled by air to water heat exchanger is carried out. • Experimental study with a substantial instrumentation at different scales is performed. • The energy efficiency of the cooling system is highlighted. • Numerical model of the system by using nodal approach is defined and validated

  13. Operation and maintenance of the cooling source

    This paper successively deals with the four main questions pertaining to operation and maintenance of the cooling source in nuclear power stations: treatment of water for cooling, watching for silt in various parts of the cooling circuit and the cleanliness of the condenser, operating and maintenance problems pertaining to the condenser (erosion, corrosion and vibratory fatigue of tubes and solutions developed) and the cooling towers (freezing and freeze protection)

  14. TEVA new cooling system from the point of view electric

    The objective of the project is to ensure that TEVA temperature reservoir discharge cooling Arrocampo the Torrejon-Tajo does not exceed the limit value 30 degree centigrade. To do this, we have installed a cooling system based on a cooling tower to which water is supplied by four main pumps 1100kW.

  15. Use of reclaimed water for power plant cooling.

    Veil, J. A.; Environmental Science Division

    2007-10-16

    Freshwater demands are steadily increasing throughout the United States. As its population increases, more water is needed for domestic use (drinking, cooking, cleaning, etc.) and to supply power and food. In arid parts of the country, existing freshwater supplies are not able to meet the increasing demands for water. New water users are often forced to look to alternative sources of water to meet their needs. Over the past few years, utilities in many locations, including parts of the country not traditionally water-poor (e.g., Georgia, Maryland, Massachusetts, New York, and North Carolina) have needed to reevaluate the availability of water to meet their cooling needs. This trend will only become more extreme with time. Other trends are likely to increase pressure on freshwater supplies, too. For example, as populations increase, they will require more food. This in turn will likely increase demands for water by the agricultural sector. Another example is the recent increased interest in producing biofuels. Additional water will be required to grow more crops to serve as the raw materials for biofuels and to process the raw materials into biofuels. This report provides information about an opportunity to reuse an abundant water source -- treated municipal wastewater, also known as 'reclaimed water' -- for cooling and process water in electric generating facilities. The report was funded by the U.S. Department of Energy's (DOE's) National Energy Technology Laboratory (NETL) Innovations for Existing Plants research program (Feeley 2005). This program initiated an energy-water research effort in 2003 that includes the availability and use of 'nontraditional sources' of water for use at power plants. This report represents a unique reference for information on the use of reclaimed water for power plant cooling. In particular, the database of reclaimed water user facilities described in Chapter 2 is the first comprehensive national effort to identify and catalog those plants that are using reclaimed water for cooling.

  16. Desiccant Dewpoint Cooling System Independent of External Water Sources

    Bellemo, Lorenzo; Elmegaard, Brian; Markussen, Wiebke B.; Kærn, Martin R.; Reinholdt, Lars O.

    2015-01-01

    This paper presents a patent pending technical solution aiming to make desiccant cooling systems independent of external water sources, hence solving problems of water availability, cost and treatment that can decrease the system attractiveness. The solution consists in condensing water from the air that regenerates the desiccant dehumidifier, and using it for running the evaporative coolers in the system. A closed regeneration circuit is used for maximizing the amount of condensed water. Thi...

  17. Methodologies for estimating air emissions from three non-traditional source categories: Oil spills, petroleum vessel loading and unloading, and cooling towers. Final report, October 1991-March 1993

    The report discusses part of EPA's program to identify and characterize emissions sources not currently accounted for by either the existing Aerometric Information Retrieval System (AIRS) or State Implementation Plan (SIP) area source methodologies and to develop appropriate emissions estimation methodologies and emission factors for a group of these source categories. Based on the results of the identification and characterization portions of this research, three source categories were selected for methodology and emission factor development: oil spills, petroleum vessel loading and unloading, and cooling towers. The report describes the category selection process and presents emissions estimation methodologies and emission factor data for the selected source categories. The discussions for each category include general background information, emissions generation activities, pollutants emitted, sources of activity and pollutant data, emissions estimation methodologies and data issues. The information used in these discussions was derived from various sources including available literature, industrial and trade association publications and contracts, experts on the category and activity, and knowledgeable federal and state personnel

  18. Effect of closed loop cooling water transit time on containment cooling

    Long term containment cooling analyses in nuclear plant systems are usually conducted assuming a quasi steady-state process, that is, a steady state evaluation of the cooling system is completed for each calculational step. In reality, fluid transport in the system, and heat addition to system components may affect the heat removal rate of the system. Transient effects occurring during system startup may affect the maximum temperatures experienced in the system. It is important to ensure that such transient effects do not affect operation of the system (e.g., cause a high temperature trip). To evaluate the effect of fluid transit delays, a closed loop cooling water system model has been developed that incorporates the fluid transport times when determining the closed loop cooling system performance. This paper describes the closed loop cooling system model as implemented in the CONTEMPT-LT/028 code. The evaluation of the transient temperature response of the closed loop cooling system using the model is described. The paper also describes the effect of fluid transit time on the overall containment cooling performance

  19. LOFA analyses for the water and helium cooled SEAFP reactors

    This study was performed in the frame of the European long-term fusion safety programme 1999 (SEAFP99). Loss of flow accidents (LOFA) have been studied for two cases, first for a helium cooled reactor with advanced dual-coolant (DUAL) blanket at 100% nominal power. The second case applies to a water-cooled reactor at 20% nominal power. Both transients were simulated with the code MELCOR 1.8.4. The results for the helium cooled reactor show that with a natural circulation flow of helium after the pump stops, the first wall temperature will stay below the temperature for excepted failure of the construction material. For the water cooled reactor, the results show that the pressurizer set point for its liquid volumetric inventory is reached before the plasma facing components attain a critical temperature. The pressurizer set point will induce a plasma shutdown

  20. Prototype solar heating and cooling systems including potable hot water

    1978-01-01

    Progress is reviewed in the development, delivery, and support of two prototype solar heating and cooling systems including potable hot water. The system consisted of the following subsystems: collector, auxiliary heating, potable hot water, storage, control, transport, and government-furnished site data acquisition.

  1. Cooling Water System Monitoring by Means of Mossbauer Spectroscopy

    Mossbauer spectroscopy have been applied to the analysis of corrosion sediments formed on mild steel coupons, which were placed in the different points of the Bourgas Petrochemical Plant Recilculating Cooling Water System. It was shown that the created corrosion products can successfully reflect the ambient water medium pollution to which the coupons were exposed

  2. Water-cooled insulated steam-injection wells

    Back, L. H.; Jaffe, L. D.

    1980-01-01

    Water is used as insulated coolant and heat-transfer medium for steam-injection oil wells. Approach is somewhat analogous to cooling system in liquid-propellant rocket. In addition to trapping and delivering heat to steam-injection point, water will also keep casing cooler, preventing or reducing casing failures caused by thermal stresses.

  3. Control of biological growth in recirculating cooling systems using treated secondary effluent as makeup water with monochloramine.

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

    2012-12-01

    Secondary-treated municipal wastewater, an abundant and widely distributed impaired water source, is a promising alternative water source for thermoelectric power plant cooling. However, excessive biological growth is a major challenge associated with wastewater reuse in cooling systems as it can interfere with normal system operation as well as enhance corrosion and scaling problems. Furthermore, possible emission of biological aerosols (e.g., Legionella pneumophila) with the cooling tower drift can lead to public health concerns within the zone of aerosol deposition. In this study, the effectiveness of pre-formed and in-situ-formed monochloramine was evaluated for its ability to control biological growth in recirculating cooling systems using secondary-treated municipal wastewater as the only makeup water source. Bench-scale studies were compared with pilot-scale studies for their ability to predict system behavior under realistic process conditions. Effectiveness of the continuous addition of pre-formed monochloramine and monochloramine formed in-situ through the reaction of free chlorine with ammonia in the incoming water was evaluated in terms of biocide residual and its ability to control both planktonic and sessile microbial populations. Results revealed that monochloramine can effectively control biofouling in cooling systems employing secondary-treated municipal wastewater and has advantages relative to use of free chlorine, but that bench-scale studies seriously underestimate biocide dose and residual requirements for proper control of biological growth in full-scale systems. Pre-formed monochloramine offered longer residence time and more reliable performance than in-situ-formed monochloramine due to highly variable ammonia concentration in the recirculating water caused by ammonia stripping in the cooling tower. Pilot-scale tests revealed that much lower dosing rate was required to maintain similar total chlorine residual when pre-formed monochloramine was used as compared to in-situ-formed monochloramine. Adjustment of biocide dose to maintain monochloramine residual above 3mg/L is needed to achieve successful biological growth control in recirculating cooling systems using secondary-treated municipal effluent as the only source of makeup water. PMID:23063442

  4. Emergency cooling of pressurized water reactors

    The operating conditions of the reactor are first described during emergency cooling (system aspect) taking as example a Westinghouse type reactor (cold branch injection). Mention is then made of the different variants employed either by Westinghouse or by other manufacturers (top of vessel injection, hot branch injection, equalizing valve, etc.). The importance of accurately knowing the pressure drops throughout the system is demonstrated. Particular attention is given to heat exchanges in the core: non-wet area, heat transfer by convection and radiation with a two-phase flow; re-wetting area, effect of axial conduction and of the condition of the fuel. Finally, the models used for the overall study of the system and for the treatment of local heat transfer, are briefly presented

  5. Assessment of requirements for dry towers

    Peterson, D E; Sonnichsen, J C

    1976-09-01

    The regional limitations of surface water supplies in the U.S. were assessed with respect to the consumptive use requirements of wet cooling towers. The study simulated unit consumptive use factors by region, assessed regional water supplies, and examined electric load projections through 2000 A.D. to ascertain where and when water limitations may occur and, therefore, where dry cooling may be required. It was concluded that the cooling water supply situation in the United States through the year 2000 is adequate in most areas, but is uncertain over much of the Southwest. The uncertainty is related to increasing competition for the available supplies and to potential Federal and/or State policy decisions that may have a significant effect on power plant cooling. Limitations on coastal siting, seismic zone constraints, and state constraints on the purchase and transfer of water rights from other uses to cooling supply have the potential of bringing wet/dry or dry cooling into relatively common use in the 1990's. (LCL)

  6. Grohnde. Documentation of the police operation during the demonstration against the NPP Grohnde on 19.03.1977 and the evacuation of the occupied cooling tower site on 23.08.1977

    The documentation of the police operation during the demonstration against the NPP Grohnde on 16.03.1977 and the evacuation of the occupied cooling tower site on 23.08.1977 covers the following issues: involved action forces: police Niedersachsen, police Nordrhein-Westfalen, police Schleswig-Holstein, police Bremen and the Bundesgrenzschutz; concept of the police operation, provisions (lodging and board) for the police, operating resources, details of the operation sequence; post-processing of the operation; the Grohnde trials.

  7. Cooling systems for new-generation units

    Three coolant circuits of the new-generation unit are described, viz., 1. the main coolant circuit for cooling the condensers and steam turbine auxiliary equipment; 2. cooling technological water circuit of the major consuming equipment; 3. cooling technological water circuit of important consuming equipment of the primary part. Of the two variants considered for the coolant piping between the main generation unit and the cooling tower, that involving a reinforced concrete tube with a steel sealing insert is the more economical one. For the new units, one cooling tower is assigned to each unit. The cooling technological water circuit of the major consuming equipment of the primary part remains virtually unchanged, identical with that of the Temelin units. The entire cooling technological water circuit of important consuming equipment of the primary part is designed as earthquake and pressure wave resistant. In the unit, the safety systems are so designed that the number of subsystems is reduced as compared with the existing WWER type reactors, viz., from 3 x 100% to 2 x 100%, while the reliability of components (in terms of failure rate) is required to be as high as with the 3x 100% design of the Temelin nuclear power plant. As regards the cooling system, the new unit is designed in three variants: cooling by means of tanks with spraying, by means of fan-type cooling towers, and by means of microtowers with an emergency makeup water reservoir for each system. (Z.S.)

  8. USE OF PRODUCED WATER IN RECIRCULATING COOLING SYSTEMS AT POWER GENERATING FACILITIES

    Michael N. DiFilippo

    2004-08-01

    The purpose of this study is to evaluate produced water as a supplemental source of water for the San Juan Generating Station (SJGS). This study incorporates elements that identify produced water volume and quality, infrastructure to deliver it to SJGS, treatment requirements to use it at the plant, delivery and treatment economics, etc. SJGS, which is operated by Public Service of New Mexico (PNM) is located about 15 miles northwest of Farmington, New Mexico. It has four units with a total generating capacity of about 1,800 MW. The plant uses 22,400 acre-feet of water per year from the San Juan River with most of its demand resulting from cooling tower make-up. The plant is a zero liquid discharge facility and, as such, is well practiced in efficient water use and reuse. For the past few years, New Mexico has been suffering from a severe drought. Climate researchers are predicting the return of very dry weather over the next 30 to 40 years. Concern over the drought has spurred interest in evaluating the use of otherwise unusable saline waters. Deliverable 2 focuses on transportation--the largest obstacle to produced water reuse in the San Juan Basin (the Basin). Most of the produced water in the Basin is stored in tanks at the well head and must be transported by truck to salt water disposal (SWD) facilities prior to injection. Produced water transportation requirements from the well head to SJGS and the availability of existing infrastructure to transport the water are discussed in this deliverable.

  9. Characteristics of cooling water fouling in a heat exchange system

    This study investigated the efficiency of the physical water treatment method in preventing and controlling fouling accumulation on heat transfer surfaces in a laboratory heat exchange system with tap and artificial water. To investigate the fouling characteristics, an experimental test facility with a plate type heat exchange system was newly built, where cooling and hot water moved in opposite directions forming a counter-flow heat exchanger. The obtained fouling resistances were used to analyze the effects of the physical water treatment on fouling mitigation. Furthermore, the surface tension and pH values of water were also measured. This study compared the fouling characteristics of cooling water in the heat exchange system with and without the mitigation methods for various inlet velocities. In the presence of the electrode devices with a velocity of 0.5m/s, the fouling resistance was reduced by 79% compared to that in the absence of electrode devices

  10. Emergency cooling system of a light water nuclear reactor

    This emergency cooling system of a light water nuclear reactor, the reactor being of the type featuring a low pressure emergency water injection system in the reactor vessel from a cold water tank connected to the top of the said vessel by a line on which a low pressure pump and at least one normally closed upstream valve are mounted in series, is characterized by the fact that it contains at least one heat exchanger built into the vessel and normally immersed in the reactor water, the circuit of the said exchanger being connected, at one of its ends, by means of a three-way valve, to the said upstream valve, and, at the other end, through a downstream valve and a second cooling heat exchanger operating with untreated water, to the said cold water tank

  11. Design and construction of immersed tube offshore cooling water tunnels at Sizewell 'B' power station

    Steam used to drive the turbine generators at Sizewell ''B'' Nuclear Power Station is cooled by passing through condensers where heat is transferred to cool sea water pumped through the Cooling Water System. The paper describes the initial investigations, design, and construction of the offshore tunnels used to draw cool water from 800m offshore and discharge the warmed water 200m offshore. (author)

  12. Heat transfer during cooling of hot surfaces by water nozzles

    M. Phoda

    2009-10-01

    Full Text Available Method of cooling in a secondary zone of continuous casting of steel has a significant influence on a quality of continuously cast products mainly from the point of view of internal and surface defects as well as zonal segregations. At the department of thermal engineering, a physical model of the secondary zone has been developed, which enables testing of both water and water-air nozzles. During laboratory measurements cooling effects of a cone nozzle have been expressed by means of three parameters. Most commonly used parameter is an admission characteristic, infrequently heat transfer coefficient is determined and newly a measuring of dynamic impact of the cooling water has been introduced.

  13. Electricity Prices, River Temperatures and Cooling Water Scarcity

    2011-01-01

    Thermal-based power stations rely on water for cooling purposes. These water sources may be subject to incidents of scarcity, environmental regulations, and competing economic concerns. This paper analyzes the effect of water scarcity and increased river temperatures on German electricity prices from 2002 to 2009. Having controlled for demand effects, the results indicate that the electricity price is significantly impacted by both a change in river temperatures and the relative abundance of ...

  14. Effect of Oxidizing Bioxides to the Microorganism Growth at RSG-GAS Secondary Cooling Water

    The RSG-GAS secondary cooling system is open recirculation cooling water. One of the problem at the recirculation open cooling water system is the microorganism growth. To control of the microorganism growth at RSG-GAS secondary cooling system carried out by addition oxidizing biocides chemical and monitoring of the microorganism growth in secondary cooling water. Monitoring of the microorganism growth carried out by determine total count of bacteria in secondary cooling water system with Dipslides Test. From the monitoring result showed that at the secondary cooling system shutdown was the microorganism growth at secondary cooling water system growth faster and than decrease growth after addition of the oxidizing biocides. (author)

  15. Potentials of heat recovery from 850C LEP cooling water

    Most of the cooling water from LEP has a too low temperature (30 to 400C) to be considered for economical recovery of energy. However, it is hoped that the heat from the klystrons be removed at a temperature of 850C and that this part of the LEP cooling water might be used for saving primary energy. In this study different possibilities have been investigated to make use of the waste heat for heating purposes during winter time, for saving energy in the refrigeration process in summer and for power generation. Cost estimates for these installations are also given and show their economic drawbacks. (orig.)

  16. Computer modeling of lime-soda softening of cooling waters

    A computer model is developed to fully describe the lime soda ash softening process. This process has a long history of being used to remove calcium and magnesium hardness from cooling waters in order to prevent scaling on heat exchangers. Softening of makeup water and/or a sidestream from the recirculating water will allow a reduction in blowdown. In the extreme case, zero blowdown may be accomplished to conserve cooling waters and to save the costs of disposing of blowdown. Cooling waters differ from most natural waters in having higher temperature and higher concentration of dissolved solids, and, therefore, a higher ionic strength. These factors plus the effects of complex formation are taken into consideration in the development of the computer model. To determine the composition of a softened water, the model assumes that an equilibrium state is reached in a reactor, and employs the equations of mass action and mass balance. The resulting nonlinear simultaneous equations are then linearized by Taylor series expansion and solved by the multidimensional Newton-Raphson method. The computer predictions are compared to the results of laboratory studies using synthetic waters

  17. Conditioning of cooling water in power stations. Feedback from twenty years of experience with acid feeding

    In the late 1970's and early 1980's, with the development of the nuclear programme in many European countries, the recirculation of cooling water in power stations became an issue which required urgent attention. The concentration of several plants of 1000 MW or more on sites along inland waterways actually made simple once-through cooling impossible, owing to the risk of an unacceptable rise in the river's water temperature. The chemical composition of natural freshwater in western European waterways is such that when it becomes slightly concentrated, scale is rapidly formed. The relatively low solubility of calcium carbonate and the degassing of the carbon dioxide during close contact between the water and air in the heat exchangers of the cooling tower explain this precipitation tendency. Fairly soon, experts in the electricity power generation companies highlighted the need for on-site, pilot loop simulations, in order to foresee the physico-chemical phenomena that could arise in industrial installations. The number of financially justifiable processing possibilities could be briefly summarised by the following three solutions: to adapt the concentration factor in order to be under the calcium carbonate solubility limit and thereby avoid the need for any water conditioning; to accept concentration factors of between 1.4 and 1.9 and control the calcium carbonate precipitation through controlled acid injection in the circulation water; to raise the concentration factor over 5 and soften the makeup water through the addition of lime and flocculant. The last of these solutions was rarely ever used in Belgium and France. It was however widely used in Germany. Its application requires a greater investment and leads to higher operating costs than acid injection. Furthermore, it leads to the problem of daily drying and disposal of several dozen tonnes of sludge, which have to be recycled or dumped. In an increasingly stringent environmental context, this solution is no longer easily justifiable. The research efforts undertaken to better understand and control calcium carbonate precipitation and scale formation have paid off and have resulted in the standardisation of the treatment process and the control procedure of the cooling circuits by ELECTRABEL. The initial experience gained in the fossil power plants of AMERCOEUR (2 x 125 MW units) was finally successfully applied to plants 2 and 3 at TIHANGE. Since then, all of the conventional or combined cycle power plants have adopted the same treatment philosophy. Six units of between 125 and 1000 MW have been treated in this manner, some of them for over twenty years, without showing any signs of scale deposits. It is true that adaptations have had to be made in the control recommendations defined during the pilot trials, in order to allow for the impact of cathodic protections and certain cooling tower fills. (authors)

  18. Conditioning of cooling water in power stations. Feedback from twenty years of experience with acid feeding

    Goffin, C.; Duvivier, L.; Girasa, E. [LABORELEC, Chemistry of Water (Belgium); Brognez, J. [ELECTRABEL, TIHANGE Nuclear Power Station (Belgium)

    2002-07-01

    In the late 1970's and early 1980's, with the development of the nuclear programme in many European countries, the recirculation of cooling water in power stations became an issue which required urgent attention. The concentration of several plants of 1000 MW or more on sites along inland waterways actually made simple once-through cooling impossible, owing to the risk of an unacceptable rise in the river's water temperature. The chemical composition of natural freshwater in western European waterways is such that when it becomes slightly concentrated, scale is rapidly formed. The relatively low solubility of calcium carbonate and the degassing of the carbon dioxide during close contact between the water and air in the heat exchangers of the cooling tower explain this precipitation tendency. Fairly soon, experts in the electricity power generation companies highlighted the need for on-site, pilot loop simulations, in order to foresee the physico-chemical phenomena that could arise in industrial installations. The number of financially justifiable processing possibilities could be briefly summarised by the following three solutions: to adapt the concentration factor in order to be under the calcium carbonate solubility limit and thereby avoid the need for any water conditioning; to accept concentration factors of between 1.4 and 1.9 and control the calcium carbonate precipitation through controlled acid injection in the circulation water; to raise the concentration factor over 5 and soften the makeup water through the addition of lime and flocculant. The last of these solutions was rarely ever used in Belgium and France. It was however widely used in Germany. Its application requires a greater investment and leads to higher operating costs than acid injection. Furthermore, it leads to the problem of daily drying and disposal of several dozen tonnes of sludge, which have to be recycled or dumped. In an increasingly stringent environmental context, this solution is no longer easily justifiable. The research efforts undertaken to better understand and control calcium carbonate precipitation and scale formation have paid off and have resulted in the standardisation of the treatment process and the control procedure of the cooling circuits by ELECTRABEL. The initial experience gained in the fossil power plants of AMERCOEUR (2 x 125 MW units) was finally successfully applied to plants 2 and 3 at TIHANGE. Since then, all of the conventional or combined cycle power plants have adopted the same treatment philosophy. Six units of between 125 and 1000 MW have been treated in this manner, some of them for over twenty years, without showing any signs of scale deposits. It is true that adaptations have had to be made in the control recommendations defined during the pilot trials, in order to allow for the impact of cathodic protections and certain cooling tower fills. (authors)

  19. New materials for cooling systems

    New materials based on rubber-vulcanite compounds and used for manufacturing cooling tower elements and coating's of hydraulic structure surfaces are proposed and their production technology is described. A series of studies on physicomechanical and chemical characteristics and hydroaerothermal parameters of cooling tower elements and coatings revealed an obvious advantage of these materials over existing ones. The materials proposed provide high efficiency of cooling tower elements, hydraulic structures and the cooling tower as a whole

  20. Purifying method of cooling water in a reactor

    Purpose: To provide a filter which has a good effect in removal of insoluble material within cooling water in a reactor, has heat resistance and has no effluent therefrom. Constitution: In order to cool non-radioactive or radioactive insoluble material within cooling water in a reactor, a filter is used in which carbon fibers as a filtering material are wound about a cylindrical porous body to form a filtering layer of which opposite ends are retained by stops. The porous body is formed of anticorrosive metal, ceramics, glass, carbon material and the like, and preferably has its diameter from 5 to 200 ?. The carbon fibers include carbonaceous fibers or graphite fibers formed of polyacrylonitrile fibers, fibrous fibers and the like and preferably have their diameter from 0.1 to 100 ?. (Yoshihara, H.)

  1. POOL WATER TREATMENT AND COOLING SYSTEM DESCRIPTION DOCUMENT

    The Pool Water Treatment and Cooling System is located in the Waste Handling Building (WHB), and is comprised of various process subsystems designed to support waste handling operations. This system maintains the pool water temperature within an acceptable range, maintains water quality standards that support remote underwater operations and prevent corrosion, detects leakage from the pool liner, provides the capability to remove debris from the pool, controls the pool water level, and helps limit radiological exposure to personnel. The pool structure and liner, pool lighting, and the fuel staging racks in the pool are not within the scope of the Pool Water Treatment and Cooling System. Pool water temperature control is accomplished by circulating the pool water through heat exchangers. Adequate circulation and mixing of the pool water is provided to prevent localized thermal hotspots in the pool. Treatment of the pool water is accomplished by a water treatment system that circulates the pool water through filters, and ion exchange units. These water treatment units remove radioactive and non-radioactive particulate and dissolved solids from the water, thereby providing the water clarity needed to conduct waste handling operations. The system also controls pool water chemistry to prevent advanced corrosion of the pool liner, pool components, and fuel assemblies. Removal of radioactivity from the pool water contributes to the project ALARA (as low as is reasonably achievable) goals. A leak detection system is provided to detect and alarm leaks through the pool liner. The pool level control system monitors the water level to ensure that the minimum water level required for adequate radiological shielding is maintained. Through interface with a demineralized water system, adequate makeup is provided to compensate for loss of water inventory through evaporation and waste handling operations. Interface with the Site Radiological Monitoring System provides continuous radiological monitoring of the pool water. The Pool Water Treatment and Cooling System interfaces with the Waste Handling Building System, Site-Generated Radiological Waste Handling System, Site Radiological Monitoring System, Waste Handling Building Electrical System, Site Water System, and the Monitored Geologic Repository Operations Monitoring and Control System

  2. Hydrogen production options for water-cooled nuclear power plants

    Supercritical water cooled reactors have the potential to reach outlet temperatures of 550oC. Although most hydrogen production technologies currently being pursued require higher temperatures, a few are compatible with these lower temperatures. Of these, low-temperature water electrolysis is the only technology currently available commercially. The high cost of electricity, however, makes hydrogen from these systems more expensive than hydrogen from current fossil- based methods. Other hydrogen production options that would be compatible with water-cooled reactors, such as membrane-assisted steam methane reforming and lower-temperature thermo- electrochemical cycles, are at various stages of research. None are close to having demonstrated commercial viability. Nonetheless, process flowsheets suggest that system efficiencies can be higher than for low-temperature water electrolysis. (author)

  3. Computational Simulation of a Water-Cooled Heat Pump

    Bozarth, Duane

    2008-01-01

    A Fortran-language computer program for simulating the operation of a water-cooled vapor-compression heat pump in any orientation with respect to gravity has been developed by modifying a prior general-purpose heat-pump design code used at Oak Ridge National Laboratory (ORNL).

  4. Hydrogen production using water cooled reactors

    Full text: Today the world is facing tremendous energy challenges. There is a demographic explosion, which even in the most conservative scenario will drive the energy demand to high levels whilst at the same time fossil resources are becoming scarcer, and more particularly oil which bears most of the weight in the transportation area. Global warming is also becoming a major concern as the last Intergovernmental Panel on Climate Change concluded that anthropogenic greenhouse gases (GHG) are responsible for most of the observed temperature increase since the middle of the twentieth century. To address these difficulties, the first step is to look for ways to save energy whenever possible. Then, the part of GHG free sources - renewable energies (wind, solar, hydraulic, biomass) as well as nuclear energy - has to be increased in electricity production. Lastly, since the part of electricity in the final consumption of energy is less than 20% worldwide, GHG free sources of energy have to look for other markets such as transportation, whether directly (electric cars) or indirectly via hydrogen (fuel cells) and/or process heat. Hydrogen is produced currently from fossil fuels (less than 5% is produced by splitting water), and production is increasing steadily, mostly because of its use for refining crude oil and the more demanding standards of purity required. This alone is already stimulating interest in producing hydrogen by sustainable means. Moreover, the hydrogen market is bound to expand soon: hydrogen has been identified as a leading candidate for transport applications. A near term solution is to use the hydrogen produced together with a carbon source (biomass, coal, waste, CO2) to make synthetic fuel. A longer term and more hypothetical development could be the direct use of hydrogen to power cars. Hydrogen could also be used in the iron and cement industries as a reducing agent and also help these CO2 intensive industries to significantly decrease their GHG emissions. The French context has also to be taken into account. More than 80% of electricity is produced by nuclear power plants and the hour to hour variations of the electricity demand have to be absorbed by having some plants operating at intermediate power over significant periods of time. This situation presents the double drawback of not taking full benefit of an expensive investment as well as having to take careful steps when going back to full power in order to preserve the fuel cladding. Hydrogen production during off peak periods could help regulate the electricity demand and operate the nuclear plants in base load. This then requires hydrogen production means that are flexible and not investment intensive, as they would be used only on a part time basis. CEA's strategy is hence to focus on processes which could be coupled to nuclear plants or renewable energy sources and thus be able to produce hydrogen in a sustainable way, by splitting the water molecule using GHG free electricity and/or heat. Low temperature electrolysis, even if it is used currently for limited amounts, is a mature technology which uses only electricity and can be generalized in the near future. However, this technology, which requires about 4 kWh of electricity per Nm of hydrogen produced, is energy intensive and therefore three advanced processes have also been investigated: High temperature steam electrolysis (HTSE), the Sulfur-Iodine (S-I) and Hybrid sulfur (HyS) thermochemical cycles. These processes look promising but the last two require the development of high temperature reactors, still necessitate extensive R and D work and will not be mature for industrial development within the next 20 years. Therefore, beside the optimization of LTE, our focus will be on HTSE, which will be available sooner and can also operate in autothermal mode, offering the capacity to be coupled to a LWR. In this paper, we will present the French road map for hydrogen production. (author)

  5. Natural Circulation Phenomena and Modelling for Advanced Water Cooled Reactors

    The role of natural circulation in advanced water cooled reactor design has been extended with the adoption of passive safety systems. Some designs utilize natural circulation to remove core heat during normal operation. Most passive safety systems used in evolutionary and innovative water cooled reactor designs are driven by natural circulation. The use of passive systems based on natural circulation can eliminate the costs associated with the installation, maintenance and operation of active systems that require multiple pumps with independent and redundant electric power supplies. However, considering the weak driving forces of passive systems based on natural circulation, careful design and analysis methods must be employed to ensure that the systems perform their intended functions. Several IAEA Member States with advanced reactor development programmes are actively conducting investigations of natural circulation to support the development of advanced water cooled reactor designs with passive safety systems. To foster international collaboration on the enabling technology of passive systems that utilize natural circulation, in 2004 the IAEA initiated a coordinated research project (CRP) on Natural Circulation Phenomena, Modelling and Reliability of Passive Systems that Utilize Natural Circulation. Three reports were published within the framework of this CRP. The first report (IAEA-TECDOC-1474) contains the material developed for the first IAEA training course on natural circulation in water cooled nuclear power plants. The second report (IAEA-TECDOC-1624) describes passive safety systems in a wide range of advanced water cooled nuclear power plant designs, with the goal of gaining insights into system design, operation and reliability. This third, and last, report summarizes the research studies completed by participating institutes during the CRP period.

  6. Investigation on flow stability of supercritical water cooled systems

    Research activities are ongoing worldwide to develop nuclear power plants with supercritical water cooled reactor (SCWR) with the purpose to achieve a high thermal efficiency and to improve their economical competitiveness. However, the strong variation of the thermal-physical properties of water in the vicinity of the pseudo-critical line results in challenging tasks in various fields, e.g. thermal-hydraulic design of a SCWR. One of the challenging tasks is to understand and to predict the dynamic behavior of supercritical water cooled systems. Although many thermal-hydraulic research activities were carried out worldwide in the past as well as in the near present, studies on dynamic behavior and flow stability of SC water cooled systems are scare. Due to the strong density variation, flow stability is expected to be one of the key items which need to be taken into account in the design of a SCWR. In the present work, the dynamic behavior and flow stability of SC water cooled systems are investigated using both numerical and theoretical approaches. For this purpose a new computer code SASC was developed, which can be applied to analysis the dynamic behavior of systems cooled by supercritical fluids. In addition, based on the assumptions of a simplified system, a theoretical model was derived for the prediction of the onset of flow instability. A comparison was made between the results obtained using the theoretical model and those from the SASC code. A good agreement was achieved. This gives the first evidence of the reliability of both the SASC code and the theoretical model

  7. Procedure for operating a heavy water cooled power reactor

    Nuclear reactors cooled by heavy water usually have equipment for fuel element exchange during operation, with the primary circuit remaining contained. This fuel element exchange equipment is expensive and complicated in many respects. According to the invention, the heavy water is therefore replaced by light water after a certain time of operation in such way that light water is led in and heavy water is led off. After the replacement, at least a quarter of the fuel elements of the reactor core is exchanged with the reactor pressure vessel being open. Then the light water serving as a shielding is replaced by heavy water, with the reactor pressure vessel being closed. The invention is of interest particularly for high-conversion reactors. (orig.)

  8. Conceptual design of a light water cooled PHWR

    A design concept of a new reactor core is proposed as a deuterium moderated pressure-tube type light-water cooled reactor (DeMoPTL). Based on the proven technology, reactor coolant system and control system would be the same as those of CANDU except for changes in fuel, coolant and calandria tubes. Slightly enriched UO2 fuel poisoned with IFBA and light water coolant would give the benefits of reduced spent fuel production, lower tritium buildup and negative temperature feedback. Safety would be enhanced by installing an additional tube outside the calandria tube to add structural reinforcement. Heavy water inside these would work as moderator and an air annulus outside would provide a large channel for emergency shutdown and cooling. Fuel discharge burnup was shown to be doubled with 2.4 w/o enriched uranium fuel and all temperature coefficient were negative. Reactor module calculations done by HELIOS showed a feasibility in nuclear design. (author)

  9. Research on water-cooled fast breeder reactors

    Based on the medium and long-term program of JNC, the feasibility study for fast breeder reactors (FBRs) including related nuclear fuel cycles has been started from the 1999 fiscal year. Various options of FBR plant systems have been selected and a concept of water-cooled FBRs is one of these options. The purpose of this paper is to research and evaluate the water-cooled FBRs on the basis of literatures. The following three concepts, which premise make use of current light water reactor technology, were selected based on the research of current studies: A high conversion BWR with high void fractions and super-flat core, a high conversion PWR using heavy water as a coolant, and a supercritical pressure light water cooled FBR in which the average coolant density is so small that the breeding is possible and which can achieve the high thermal efficiency over 40%. Features of each concept were reviewed and then evaluation was performed from the following three viewpoints: The long-term targets (subject to safety, market competitiveness as an energy system, utilization of uranium resources, reduction of radioactive waste, security of the non-proliferation), the technical possibility (the structure integrity including the earthquake resistance, safety, productivity, operability and maintenance repair, difficulty of the development) and development risk. The evaluation showed that there was no problem with high developmental risk although it is difficult to achieve a high breeding ratio. However, it is desirable to confirm the thermal hydraulics of the core. Furthermore, as regards the high conversion BWR, whose study progressed the most so far, the fundamental feasibility of the breeding core was confirmed, since the method of the nuclear calculation was verified for the configuration of this study and criteria of design basis events were satisfied in the evaluation. In the 2000 fiscal year, evaluation will be made above nuclear characteristics, reactor safety and market competitiveness as an energy system for the water-cooled FBRs. (author)

  10. Thermo hydraulic analysis and control of the HELOKA water cooling system

    In the framework of the European Fusion Program, various Helium cooled Test Blanket Modules (TBM), such as the Helium Cooled Pebble Bed (HCPB) blanket, are proposed for tests under reactor relevant experimental conditions in ITER. To qualify the TBM module design for ITER, it is necessary to test full size mock-ups in a helium loop under realistic pressure, temperature and flow conditions. The HCPB mock-ups will be tested at the Helium Loop Karlsruhe (HELOKA) test facility, at present in advanced status of design. As far as possible, HELOKA shall operate with requirements similar to those of the Helium coolant circuit of the TBM modules in ITER. One of the main requirements of the ITER main helium loop is its ancillary water cooling system, hence the need of a Water Cooling System (WCS) for HELOKA. An existing WCS, recently used for the COMET (Core Melt Accidents) experiment, is foreseen for this purpose. The system, designed in the 80's for a heat load of about 7 MW, will be used first for the HELOKA TBM experimental campaign, where the maximum expected heat load does not exceed 5 MW, and later on, for the Test Divertor Modules (TDM). The thermal hydraulic effect has been studied using the system code RELAP5, where the pumps, the heat exchanger (HX), the cooling tower, the valves, the piping, etc., can be modeled and the whole loop can be simulated for steady state, transient accident processes or cyclic operation. In order to improve the efficiency of the system and save energy, it has been proposed to install variable frequency converters for the electric drivers and new feedback controllers. An evaluation of the overall performances of the system with the proposed feedback controllers has been conducted with computer models developed with SIMULINK. At present most of the components have been modeled using manufacturer's data. For some components, technical data are scarce and therefore a comparison with experimental data to validate the models is planned. After the validation based on the experimental data, the code will allow the testing of the control strategies for steady state, transients or cyclic operation and check the possible upgrade of the system to 10 MW (expected heat load for the HELOKA TDM experimental campaign). The control system is being modernized using state of the art hardware and software components. The upgrade also includes additional sensors and a new data acquisition system. (author)

  11. Conceptual design of a water cooled breeder blanket for CFETR

    Liu, Songlin, E-mail: slliu@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui 230031 (China); Pu, Yong; Cheng, Xiaoman [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui 230031 (China); Li, Jia; Peng, ChangHong [School of Nuclear Science and Technology, University of Science and Technology of China, Hefei, Anhui 230027 (China); Ma, Xuebing [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui 230031 (China); Chen, Lei [School of Nuclear Science and Technology, University of Science and Technology of China, Hefei, Anhui 230027 (China)

    2014-10-15

    Highlights: • We proposed a water cooled ceramic breeder blanket with superheated steam. • Superheated steam is generated at the first wall and the front part of breeder zone. • Superheated steam has negligible impact on neutron absorption by coolant in FW and improves TBR. • The superheated steam at higher temperature can improve thermal efficiency. - Abstract: China Fusion Engineering Test Reactor (CFETR) is an ITER-like superconducting tokamak reactor. Its major radius is 5.7 m, minor radius is 1.6 m and elongation ratio is 1.8. Its mission is to achieve 50–200 MW of fusion power, 30–50% of duty time factor, and tritium breeding ratio not less than 1.2 to ensure the self-sufficiency. As one of the breeding blanket candidates for CFETR, a water cooled breeder blanket with superheated steam is proposed and its conceptual design is being carried out. In this design, sub-cooling water at 265 °C under the pressure of 7 MPa is fed into cooling plates in breeding zone and is heated up to 285 °C with saturated steam generated, and then this steam is pre-superheated up to 310 °C in first wall (FW), final, the pre-superheated steam coming from several blankets is fed into the other one blanket to superheat again up to 517 °C. Due to low density of superheated steam, it has negligible impact on neutron absorption by coolant in FW so that the high energy neutrons entering into breeder zone moderated by water in cooling plate help enhance tritium breeding by {sup 6}Li(n,α)T reaction. Li{sub 2}TiO{sub 3} pebbles and Be{sub 12}Ti pebbles are chosen as tritium breeder and neutron multiplier respectively, because Li{sub 2}TiO{sub 3} and Be{sub 12}Ti are expected to have better chemical stability and compatibility with water in high temperature. However, Be{sub 12}Ti may lead to a reduction in tritium breeding ratio (TBR). Furthermore, a spot of sintered Be plate is used to improve neutron multiplying capacity in a multi-layer structure. As one alternative option, in spite of lower TBR, Pb is taken into account to replace Be plate in viewpoint of safety. In this contribution, study on neutronics and thermal design for a water cooled breeder blanket with superheated steam is reported.

  12. Conceptual design of a water cooled breeder blanket for CFETR

    Highlights: We proposed a water cooled ceramic breeder blanket with superheated steam. Superheated steam is generated at the first wall and the front part of breeder zone. Superheated steam has negligible impact on neutron absorption by coolant in FW and improves TBR. The superheated steam at higher temperature can improve thermal efficiency. - Abstract: China Fusion Engineering Test Reactor (CFETR) is an ITER-like superconducting tokamak reactor. Its major radius is 5.7 m, minor radius is 1.6 m and elongation ratio is 1.8. Its mission is to achieve 50200 MW of fusion power, 3050% of duty time factor, and tritium breeding ratio not less than 1.2 to ensure the self-sufficiency. As one of the breeding blanket candidates for CFETR, a water cooled breeder blanket with superheated steam is proposed and its conceptual design is being carried out. In this design, sub-cooling water at 265 C under the pressure of 7 MPa is fed into cooling plates in breeding zone and is heated up to 285 C with saturated steam generated, and then this steam is pre-superheated up to 310 C in first wall (FW), final, the pre-superheated steam coming from several blankets is fed into the other one blanket to superheat again up to 517 C. Due to low density of superheated steam, it has negligible impact on neutron absorption by coolant in FW so that the high energy neutrons entering into breeder zone moderated by water in cooling plate help enhance tritium breeding by 6Li(n,?)T reaction. Li2TiO3 pebbles and Be12Ti pebbles are chosen as tritium breeder and neutron multiplier respectively, because Li2TiO3 and Be12Ti are expected to have better chemical stability and compatibility with water in high temperature. However, Be12Ti may lead to a reduction in tritium breeding ratio (TBR). Furthermore, a spot of sintered Be plate is used to improve neutron multiplying capacity in a multi-layer structure. As one alternative option, in spite of lower TBR, Pb is taken into account to replace Be plate in viewpoint of safety. In this contribution, study on neutronics and thermal design for a water cooled breeder blanket with superheated steam is reported

  13. Modeling and energy simulation of the variable refrigerant flow air conditioning system with water-cooled condenser under cooling conditions

    Li, Yueming; Wu, Jingyi [Shanghai Jiao Tong University, Institute of Refrigeration and Cryogenics (China); Shiochi, Sumio [Daikin Industries Ltd. (Japan)

    2009-09-15

    As a new system, variable refrigerant flow system with water-cooled condenser (water-cooled VRF) can offer several interesting characteristics for potential users. However, at present, its dynamic simulation simultaneously in association with building and other equipments is not yet included in the energy simulation programs. Based on the EnergyPlus's codes, and using manufacturer's performance parameters and data, the special simulation module for water-cooled VRF is developed and embedded in the software of EnergyPlus. After modeling and testing the new module, on the basis of a typical office building in Shanghai with water-cooled VRF system, the monthly and seasonal cooling energy consumption and the breakdown of the total power consumption are analyzed. The simulation results show that, during the whole cooling period, the fan-coil plus fresh air (FPFA) system consumes about 20% more power than the water-cooled VRF system does. The power comparison between the water-cooled VRF system and the air-cooled VRF system is performed too. All of these can provide designers some ideas to analyze the energy features of this new system and then to determine a better scheme of the air conditioning system. (author)

  14. Review of fuel failures in water cooled reactors

    In spite of the low fuel failure rate in currently operating water cooled nuclear power reactors, there is a continued high level of interest in fuel failures, for two reasons. First, the problems and inconvenience caused by fuel failures in plant operations can still be significant. Second, the generally accepted goal of achieving a zero failure rate requires detailed knowledge of existing failure mechanisms, their root causes and remedies. Against this background, and following a recommendation by the Technical Working Group on Fuel Performance and Technology (TWGFPT), the IAEA decided to update an earlier study on fuel failures, Review of Fuel Failures in Water Cooled Reactors (Technical Reports Series No. 388), study data from different water cooled reactor types, including LWR, PWR, BWR, WWER and heavy water CANDU/PHWR types, and to gather as much experience as possible. Fuel failure statistics were derived from a questionnaire distributed to all TWGFPT members and through analysis of available publications. This review provides information on all aspects of fuel failures in current nuclear power plant operations

  15. Corrosion induced clogging and plugging in water-cooled generator cooling circuit

    Water-cooled electrical generators have been experienced corrosion-related problems that are restriction of flow through water strainers caused by collection of excessive amounts of copper corrosion products (''clogging''), and restriction of flow through the copper strands in the stator bars caused by growth or deposition of corrosion products on the walls of the hollow strands (''plugging''). These phenomena result in unscheduled shutdowns that would be a major concern because of the associated loss in generating capacity. Water-cooled generators are operated in one of two modes. They are cooled either with aerated water (dissolved oxygen >2 ppm) or with deaerated water (dissolved oxygen <50 ppb). Both modes maintain corrosion rates at satisfactorily low levels as long as the correct oxygen concentrations are maintained. However, it is generally believed that very much higher copper corrosion rates result at the intermediate oxygen concentrations of 100-1000 ppb. Clogging and plugging are thought to be associated with these intermediate concentrations, and many operators have suggested that the period of change from high-to-low or from low-to-high oxygen concentration is particularly damaging. In order to understand the detailed mechanism(s) of the copper oxide formation, release and deposition and to identify susceptible conditions in the domain of operating variables, a large-scale experiments are conducted using six hollow strands of full length connected with physico-chemically scaled generator cooling water circuit. To ensure a close simulation of thermal-hydraulic conditions in a generator stator, strands of the loop will be ohmically heated using AC power supply. Experiments is conducted to cover oxygen excursions in both high dissolved oxygen and low dissolved oxygen conditions that correspond to two representative operating condition at fields. A thermal upset condition is also simulated to examine the impact of thermal stress. During experiments, particle size distribution and microstructure of copper surface as well as water pH, conductivity and ORP, dissolved gases including oxygen and hydrogen is monitored as on-line. (authors)

  16. USE of mine pool water for power plant cooling.

    Veil, J. A.; Kupar, J. M .; Puder, M. G.

    2006-11-27

    Water and energy production issues intersect in numerous ways. Water is produced along with oil and gas, water runs off of or accumulates in coal mines, and water is needed to operate steam electric power plants and hydropower generating facilities. However, water and energy are often not in the proper balance. For example, even if water is available in sufficient quantities, it may not have the physical and chemical characteristics suitable for energy or other uses. This report provides preliminary information about an opportunity to reuse an overabundant water source--ground water accumulated in underground coal mines--for cooling and process water in electric generating facilities. The report was funded by the U.S. Department of Energy's (DOE's) National Energy Technology Laboratory (NETL), which has implemented a water/energy research program (Feeley and Ramezan 2003). Among the topics studied under that program is the availability and use of ''non-traditional sources'' of water for use at power plants. This report supports NETL's water/energy research program.

  17. Application of Pulsed Electrical Fields for Advanced Cooling and Water Recovery in Coal-Fired Power Plant

    Young Cho; Alexander Fridman

    2009-04-02

    The overall objective of the present work was to develop technologies to reduce freshwater consumption in a cooling tower of coal-based power plant so that one could significantly reduce the need of make-up water. The specific goal was to develop a scale prevention technology based an integrated system of physical water treatment (PWT) and a novel filtration method so that one could reduce the need for the water blowdown, which accounts approximately 30% of water loss in a cooling tower. The present study investigated if a pulsed spark discharge in water could be used to remove deposits from the filter membrane. The test setup included a circulating water loop and a pulsed power system. The present experiments used artificially hardened water with hardness of 1,000 mg/L of CaCO{sub 3} made from a mixture of calcium chloride (CaCl{sub 2}) and sodium carbonate (Na{sub 2}CO{sub 3}) in order to produce calcium carbonate deposits on the filter membrane. Spark discharge in water was found to produce strong shockwaves in water, and the efficiency of the spark discharge in cleaning filter surface was evaluated by measuring the pressure drop across the filter over time. Results showed that the pressure drop could be reduced to the value corresponding to the initial clean state and after that the filter could be maintained at the initial state almost indefinitely, confirming the validity of the present concept of pulsed spark discharge in water to clean dirty filter. The present study also investigated the effect of a plasma-assisted self-cleaning filter on the performance of physical water treatment (PWT) solenoid coil for the mitigation of mineral fouling in a concentric counterflow heat exchanger. The self-cleaning filter utilized shockwaves produced by pulse-spark discharges in water to continuously remove scale deposits from the surface of the filter, thus keeping the pressure drop across the filter at a relatively low value. Artificial hard water was used in the present fouling experiments for three different cases: no treatment, PWT coil only, and PWT coil plus self-cleaning filter. Fouling resistances decreased by 59-72% for the combined case of PWT coil plus filter compared with the values for no-treatment cases. SEM photographs showed much smaller particle sizes for the combined case of PWT coil plus filter as larger particles were continuously removed from circulating water by the filter. The x-ray diffraction data showed calcite crystal structures for all three cases.

  18. Water Cooled TJ Dense Array Modules for Parabolic Dishes

    AZUR SPACE Solar Power GmbH has developed a novel type of dense array module for use in parabolic dishes. Such dishes never produce a perfectly homogeneous, rectangular light spot but an inhomogeneous light distribution. A regular module would use this light distribution very inefficiently. Therefore AZUR SPACE developed a dense array module concept which can be adapted to inhomogeneous light spots. It is populated with state of the art triple junction solar cells.The modules are designed for light intensities in the range of 50-100 W/cm2 and are actively water cooled. Prototypes are installed in 11 m2 parabolic dishes produced by Zenith Solar. A peak output of 2.3 kW electrical and 5.5 kW thermal power could be demonstrated. The thermal power may be used for solar heating, solar cooling or warm water.

  19. Balancing passive and active systems for evolutionary water cooled reactors

    Advanced concepts of the water-cooled reactors are intended to improve safety, economics and public perception of nuclear power. The potential inclusion of new passive means in addition or instead of traditional active systems is being considered by nuclear plant designers to reach these goals. With respect to plant safety, application of the passive means is mainly intended to simplify the safety systems and to improve their reliability, to mitigate the effect of human errors and equipment malfunction. However, some clear drawbacks and the limited experience and testing of passive systems may raise additional questions that have to be addressed in the design process for each advanced reactor. Therefore the plant designer should find a reasonable balance of active and passive means to effectively use their advantages and compensate their drawbacks. Some considerations that have to be taken into account when balancing active/passive means in advanced water-cooled reactors are discussed in this paper. (author)

  20. Passive safety features in current and future water cooled reactors

    Better understanding of the passive safety systems and components in current and future water-cooled reactors may enhance the safety of present reactors, to the extend passive features are backfitted. This better understanding should also improve the safety of future reactors, which can incorporate more of these features. Passive safety systems and components may help to prevent accidents, core damage, or release radionuclides to the environment. The Technical Committee Meeting which was hosted by the USSR State Committee for Utilization of Nuclear Energy was attended by about 80 experts from 16 IAEA Member States and the NEA-OECD. A total of 21 papers were presented during the meeting. The objective of the meeting was to review and discuss passive safety systems and features of current and future water cooled reactor designs and to exchange information in this area of activity. A separate abstract was prepared for each of the 21 papers published in this proceedings. Refs, figs and tabs

  1. Economic competitiveness requirements for evolutionary water cooled reactors

    This paper analyses the necessary economic conditions for evolutionary water cooled reactors to be competitive. Utilising recent national cost data for fossil-fired base load plants expected to be commissioned by 2005 -2010, target costs for nuclear power plants are discussed. Factors that could contribute to the achievement of those targets by evolutionary water cooled reactors are addressed. The feed-back from experience acquired in implementing nuclear programmes is illustrated by some examples from France and the Republic of Korea. The paper discusses the impacts on nuclear power competitiveness of globalisation and deregulation of the electricity market and privatisation of the electricity sector. In addition, issues related to external cost internalisation are considered. (author)

  2. Elimination of deionized cooling water requirement for microchannel-cooled laser diode arrays

    Feeler, Ryan; Coleman, Steve; Levy, Joe; Stephens, Ed

    2007-02-01

    Northrop Grumman / Cutting Edge Optronics has developed three designs for microchannel-cooled laser diode arrays in which the coolant is electrically isolated from the current path. As a result, these arrays do not require the use of deionized water. The thermal performance of two of these designs is presented and, in one case, shown to far exceed the performance of standard copper microchannel-cooled packages. Also presented is a microchannel cooler made from ceramic material. This design leverages existing technology to create a low-cost, high-performance alternative to copper-based microchannel coolers. This approach offers the greatest promise for future development due to the vast assortment of existing capabilities that have already been developed for similar ceramic structures used in the electronics industry.

  3. Advanced technologies for water cooled reactors 1990. Pt. 2

    The main purpose of the meeting was to review and discuss the status of national programmes, the progress achieved since the last meeting held in June 1988 in the field of advanced technologies and design trends for existing and future water cooled reactors. 24 specialists from 14 countries and the IAEA took part in the meeting and 12 papers were presented. A separate abstract was prepared for each of these papers. Refs, figs and tabs

  4. Effect of Cooling Water on Stability of NLC Linac Components

    Le Pimpec, F; Asiri, F; Boffo, C; Bowden, G B; Carter, H; Dell'Orco, D; Doyle, E; McKee, B; Seryi, Andrei

    2002-01-01

    Vertical vibration of linac components (accelerating structures, girders and quadrupoles) in the NLC has been studied experimentally and analytically. Effects such as structural resonances and vibration caused by cooling water both in accelerating structures and quadrupoles have been considered. Experimental data has been compared with analytical predictions and simulations using ANSYS. A design, incorporating the proper decoupling of structure vibrations from the linac quadrupoles, is being pursued.

  5. The determinants of thermal comfort in cool water.

    Guéritée, J; House, J R; Redortier, B; Tipton, M J

    2015-10-01

    Water-based activities may result in the loss of thermal comfort (TC). We hypothesized that in cooling water, the hands and feet would be responsible. Supine immersions were conducted in up to five clothing conditions (exposing various regions), as well as investigations to determine if a "reference" skin temperature (Tsk) distribution in thermoneutral air would help interpret our findings. After 10 min in 34.5 °C water, the temperature was decreased to 19.5 °C over 20 min; eight resting or exercising volunteers reported when they no longer felt comfortable and which region was responsible. TC, rectal temperature, and Tsk were measured. Rather than the extremities, the lower back and chest caused the loss of overall TC. At this point, mean (SD) chest Tsk was 3.3 (1.7) °C lower than the reference temperature (P = 0.005), and 3.8 (1.5) °C lower for the back (P = 0.002). Finger Tsk was 3.1 (2.7) °C higher than the reference temperature (P = 0.037). In cool and cooling water, hands and feet, already adapted to colder air temperatures, will not cause discomfort. Contrarily, more discomfort may arise from the chest and lower back, as these regions cool by more than normal. Thus, Tsk distribution in thermoneutral air may help understand variations in TC responses across the body. PMID:25440756

  6. Koeberg's cooling water marine basin next on agenda

    The first nuclear power plant on the African continent will be South Africa's Koeberg plant which is to consist of two 922 MW PWR units. The plant is based on the French plant Tricastin but varies in its use of sea-water for cooling and its design solution for seismic effects. Brief details are given of the organisations involved, financing, and site development. (U.K.)

  7. Effect of cooling water on stability of NLC linac components

    F. Le Pimpec et al.

    2003-02-11

    Vertical vibration of linac components (accelerating structures, girders and quadrupoles) in the NLC has been studied experimentally and analytically. Effects such as structural resonances and vibration caused by cooling water both in accelerating structures and quadrupoles have been considered. Experimental data has been compared with analytical predictions and simulations using ANSYS. A design, incorporating the proper decoupling of structure vibrations from the linac quadrupoles, is being pursued.

  8. CLASSIFICATION OF THE MGR POOL WATER TREATMENT AND COOLING SYSTEM

    The purpose of this analysis is to document the Quality Assurance (QA) classification of the Monitored Geologic Repository (MGR) pool water treatment and cooling system structures, systems and components (SSCs) performed by the MGR Safety Assurance Department. This analysis also provides the basis for revision of YMP/90-55Q, Q-List (YMP 1998). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333P, ''Quality Assurance Requirements and Description'' (QARD) (DOE 1998)

  9. Advanced technologies for water cooled reactors 1990. Pt. 1

    The meeting was attended by 20 participants from 12 countries who reviewed and discussed the status and progress of national programmes on advanced water-cooled reactors and recommended to the Scientific Secretary a comprehensive programme for 1991/1992 which would support technology development programmes in IWGATWR Member States. This summary report outlines the activities of IWGATWR since its Second Meeting in June 1988 and main results of the Third Meeting

  10. Halogen compatible treatment programs for open recirculating cooling water systems

    Kessler, S.M.; Given, K.M.

    1999-07-01

    Stabilized phosphate cooling water programs have been exceptionally effective and well established in the marketplace for close to twenty years. Identification of this technology allowed chromate to be eliminated from open recirculating systems, providing less toxic operating conditions. However, very good control of stabilized phosphate applications is necessary in order to ensure chrome-like corrosion and deposit control performance. Difficulties with stabilized phosphate technology have occurred when it is used along with chlorine. Elevated chlorine dosages are sometimes necessary for microbial control. When this occurs, copper induced pitting becomes a concern as does the degradation of the cooling water program itself, i.e. phosphonate reversion. New programs have been identified which maintain their component integrity in the presence of chlorine. They offer improved deposit control performance under a variety of stressed cooling water conditions by using select polymer blends, as opposed to a single polymer. They also incorporate a new azole corrosion inhibition chemistry which minimizes copper-induced pitting associated with over-chlorination. Laboratory and field experience with this technology is discussed.

  11. Experimental Studies of NGNP Reactor Cavity Cooling System With Water

    Corradini, Michael; Anderson, Mark; Hassan, Yassin; Tokuhiro, Akira

    2013-01-16

    This project will investigate the flow behavior that can occur in the reactor cavity cooling system (RCCS) with water coolant under the passive cooling-mode of operation. The team will conduct separate-effects tests and develop associated scaling analyses, and provide system-level phenomenological and computational models that describe key flow phenomena during RCCS operation, from forced to natural circulation, single-phase flow and two-phase flow and flashing. The project consists of the following tasks: Task 1. Conduct separate-effects, single-phase flow experiments and develop scaling analyses for comparison to system-level computational modeling for the RCCS standpipe design. A transition from forced to natural convection cooling occurs in the standpipe under accident conditions. These tests will measure global flow behavior and local flow velocities, as well as develop instrumentation for use in larger scale tests, thereby providing proper flow distribution among standpipes for decay heat removal. Task 2. Conduct separate-effects experiments for the RCCS standpipe design as two-phase flashing occurs and flow develops. As natural circulation cooling continues without an ultimate heat sink, water within the system will heat to temperatures approaching saturation , at which point two-phase flashing and flow will begin. The focus is to develop a phenomenological model from these tests that will describe the flashing and flow stability phenomena. In addition, one could determine the efficiency of phase separation in the RCCS storage tank as the two-phase flashing phenomena ensues and the storage tank vents the steam produced. Task 3. Develop a system-level computational model that will describe the overall RCCS behavior as it transitions from forced flow to natural circulation and eventual two-phase flow in the passive cooling-mode of operation. This modeling can then be used to test the phenomenological models developed as a function of scale.

  12. Virtual Tower

    The primary responsibility of an intrusion detection system (IDS) operator is to monitor the system, assess alarms, and summon and coordinate the response team when a threat is acknowledged. The tools currently provided to the operator are somewhat limited: monitors must be switched, keystrokes must be entered to call up intrusion sensor data, and communication with the response force must be maintained. The Virtual tower is an operator interface assembled from low-cost commercial-off-the-shelf hardware and software; it enables large amounts of data to be displayed in a virtual manner that provides instant recognition for the operator and increases assessment accuracy in alarm annunciator and control systems. This is accomplished by correlating and fusing the data into a 360-degree visual representation that employs color, auxiliary attributes, video, and directional audio to prompt the operator. The Virtual Tower would be a valuable low-cost enhancement to existing systems

  13. Virtual Tower

    Wayne, R.A. [Sandia National Labs., Albuquerque, NM (United States). Security Engineering Dept.

    1997-08-01

    The primary responsibility of an intrusion detection system (IDS) operator is to monitor the system, assess alarms, and summon and coordinate the response team when a threat is acknowledged. The tools currently provided to the operator are somewhat limited: monitors must be switched, keystrokes must be entered to call up intrusion sensor data, and communication with the response force must be maintained. The Virtual tower is an operator interface assembled from low-cost commercial-off-the-shelf hardware and software; it enables large amounts of data to be displayed in a virtual manner that provides instant recognition for the operator and increases assessment accuracy in alarm annunciator and control systems. This is accomplished by correlating and fusing the data into a 360-degree visual representation that employs color, auxiliary attributes, video, and directional audio to prompt the operator. The Virtual Tower would be a valuable low-cost enhancement to existing systems.

  14. Solar power towers

    Etievant, M. C.

    1982-11-01

    Experimental solar power towers actually in construction or already in existence in the world are described. Seven of these installations are examined: three involve water vapor with solar superheating (EURELIOS, CESA 1, SOLAR ONE); two involve saturated water vapor (NIO, CES 5); one involves sodium (SSPS, CRS), and one molten salt (TEMIS). The principal characteristics of these receivers are presented as well as some results of economic studies of heliostat construction and the cost of electricity.

  15. W-030, AY/AZ tank farm cooling and miscellaneous instrumentation

    This is the acceptance test report for construction functional testing of Project W-030 cooling systems and related instrumentation. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The Tank Farm Cooling System consists of four forced draft cooling towers, a chilled water system, and associated controls

  16. Monitoring temporal opacity fluctuations of large structures with muon radiography: a calibration experiment using a water tower

    Jourde, Kevin; Gibert, Dominique; Marteau, Jacques; de Bremond d’Ars, Jean; Gardien, Serge; Girerd, Claude; Ianigro, Jean-Christophe

    2016-01-01

    Usage of secondary cosmic muons to image the geological structures density distribution significantly developed during the past ten years. Recent applications demonstrate the method interest to monitor magma ascent and volcanic gas movements inside volcanoes. Muon radiography could be used to monitor density variations in aquifers and the critical zone in the near surface. However, the time resolution achievable by muon radiography monitoring remains poorly studied. It is biased by fluctuation sources exterior to the target, and statistically affected by the limited number of particles detected during the experiment. The present study documents these two issues within a simple and well constrained experimental context: a water tower. We use the data to discuss the influence of atmospheric variability that perturbs the signal, and propose correction formulas to extract the muon flux variations related to the water level changes. Statistical developments establish the feasibility domain of muon radiography monitoring as a function of target thickness (i.e. opacity). Objects with a thickness comprised between ≈50 ± 30 m water equivalent correspond to the best time resolution. Thinner objects have a degraded time resolution that strongly depends on the zenith angle, whereas thicker objects (like volcanoes) time resolution does not. PMID:26971718

  17. An overview of Supercritical Water-Cooled Reactor (SCWR) concepts

    Gupta, S.; Pioro, I. [Univ. of Ontario Inst. of Technology, Faculty of Energy Systems and Nuclear Science, Oshawa, Ontario (Canada)

    2014-09-15

    Nuclear energy will playa big part in being part of the future energy mix since it offers a relatively clean, safe and reliable source of energy. Next generation nuclear energy technologies (Generation IV) are being developed around the world that offers innovative core designs and fuel cycles. Supercritical Fluids (SCFs) have been proposed for Gen IV thermodynamic cycles to achieve high thermal efficiencies. Super Critical Water-Cooled Reactor (SCWR) is one of the proposed Gen IV design relying heavily on the use of SC Water for heat transfer. This abstract presents the latest developments on SCWR concepts around the world. (author)

  18. Passive subsystem of emergency core cooling of pressurized water reactor

    Between the accident accumulator, resp. the storage tank and the primary circuit or the reactor an injector is inserted in the pipe of cooling borated water whose propelling nozzle is directly or indirectly connected to the secondary side of the steam generator, resp. to the secondary circuit of the power plant. In the steam supply pipe between the steam generator and the accident accumulator is located a pressure reducing supply valve. In the pipe of the borated water a heat exchanger is placed before the injector. (M.D.)

  19. Cooled sea water releasing device for nuclear power plant

    In a water releasing device for releasing warm sea water after cooling in a coastal nuclear power plant from a reservoir disposed higher than the sea level in a full tide by way of a syphon pipe, an ejector device is disposed for drawing air at the top of the syphon pipe into the releasing water flow by the flowrate thereof. Since the warm sea water is released below the surface of the sea directly by way of the syphon tube beyond a bank, collision of the released water flow against the surface of the sea is not caused, so that the air is not involved to the sea water by collision. Accordingly, even when a great amount of warm sea water is released continuously from a high position, the amount of air bubbles generated on the surface of the sea where the water is released in small, and there is no worry of causing cloudy state of the sea water in the vicinity thereof. Even if air is going to stay in a air sump at the inner top of the syphon pipe, since it is drawn and discharged by the energy of the released water flow by the ejector, there is no worry of interrupting the drawing state of the syphon. (N.H.)

  20. The urban infrastructural landscape in transition: Lauttasaari water tower, from technological monument to recreational place

    Saari, Heini-Emilia

    2015-01-01

    This Masters Thesis addresses the urban infrastructure of water as a medium connecting nature, the society and technology. Infrastructure is understood as a socio-technical system and a shared platform for interaction between objects. Water is the core infrastructure for human life, and moreover, the infrastructure for transporting and treating water forms the foundation of urban settlement. Yet the development of infrastructural systems has removed the experience of water from the urban rea...

  1. Some aspects of cooling water discharges and environmental enhancement

    As a consequence of the effects of cooling water discharge on the environment, the siting of nuclear power plants is approached with cautiousness. The pros and cons are discussed of siting near bodies of good quality water or in more densely populated or industrial areas. Properties and effects of thermal discharges are elaborated. The effects of heat on the activity of individual organisms, on the accumulation of organic material, on the mineralization rate of organic matter and on the transport of oxygen all have influences on recipient water bodies. Examples of siting Swedish thermal power stations are described and these indicate some negative effects. However, the results do not repudiate the possibility of good effects from the design of new cooling water intake and discharge systems that would speed up the mineralization of organic matters by addition of heat and oxygen. It is concluded that, when choosing between possible sites, areas should be selected where the available energy of the discharge can be used to improve water quality. (author)

  2. Modelization of cooling system components

    In the site evaluation study for licensing a new nuclear power facility, the criteria involved could be grouped in health and safety, environment, socio-economics, engineering and cost-related. These encompass different aspects such as geology, seismology, cooling system requirements, weather conditions, flooding, population, and so on. The selection of the cooling system is function of different parameters as the gross electrical output, energy consumption, available area for cooling system components, environmental conditions, water consumption, and others. Moreover, in recent years, extreme environmental conditions have been experienced and stringent water availability limits have affected water use permits. Therefore, modifications or alternatives of current cooling system designs and operation are required as well as analyses of the different possibilities of cooling systems to optimize energy production taking into account water consumption among other important variables. There are two basic cooling system configurations: - Once-through or Open-cycle; - Recirculating or Closed-cycle. In a once-through cooling system (or open-cycle), water from an external water sources passes through the steam cycle condenser and is then returned to the source at a higher temperature with some level of contaminants. To minimize the thermal impact to the water source, a cooling tower may be added in a once-through system to allow air cooling of the water (with associated losses on site due to evaporation) prior to returning the water to its source. This system has a high thermal efficiency, and its operating and capital costs are very low. So, from an economical point of view, the open-cycle is preferred to closed-cycle system, especially if there are no water limitations or environmental restrictions. In a recirculating system (or closed-cycle), cooling water exits the condenser, goes through a fixed heat sink, and is then returned to the condenser. This configuration results in relatively low water withdrawal. Typical heat sink options for closed-cycle systems are wet cooling system (mechanical or natural draft cooling towers, and cooling ponds). When water availability is low, a dry cooling system may be utilized. Dry cooling can be either direct or indirect and in each case uses convective heat transfer to provide cooling, eliminating evaporation losses. An innovative indirect dry cooling system is the HellerR System. The HellerR System air moving equipment can be either a natural draft or a mechanical draft. The HellerR System design concepts and equipment provides the maximum possible availability and minimum maintenance. Also, it is totally environmental-friend as saves water equivalent to the consumption of a town of 50,000 inhabitants for each 100 MWe facilitating the licensing of power projects. (authors)

  3. Technology for Water Treatment

    1992-01-01

    There are approximately 500,000 water cooling towers in the United States, all of which must be kept clear of "scale" and corrosion and free of pollutants and bacteria. Electron Pure, Ltd. manufactures a hydro cooling tower conditioner as well as an automatic pool sanitizer. The pool sanitizer consists of two copper/silver electrodes placed in a chamber mounted in the pool's recirculation system. The tower conditioner combines the ionization system with a water conditioner, pump, centrifugal solids separator and timer. The system saves water, eliminates algae and operates maintenance and chemical free. The company has over 100 distributors in the U.S. as well as others in 20 foreign countries. The buildup of scale and corrosion is the most costly maintenance problem in cooling tower operation. Jet Propulsion Laboratory successfully developed a non-chemical system that not only curbed scale and corrosion, but also offered advantages in water conservation, cost savings and the elimination of toxic chemical discharge. In the system, ozone is produced by an on-site generator and introduced to the cooling tower water. Organic impurities are oxidized, and the dissolved ozone removes bacteria and scale. National Water Management, a NASA licensee, has installed its ozone advantage systems at some 200 cooling towers. Customers have saved money and eliminated chemical storage and discharge.

  4. Justifying plans to improve performance of an existing cooling system

    Burns, J. [Stone & Webster Engineering Corp., Boston, MA (United States); Godard, D.; Randall, R. [Niagara-Mohawk Power Company, Syracuse, NY (United States); Cooper, J. [Cooper & Associates, P.A., Tampa, FL (United States)

    1996-08-01

    This paper discusses the kinds of quantitative justification needed to convince today`s cost-conscious, informed utility management that proposed improvements to the cooling system are feasible and will be of strong economic benefit to the station. It summarizes the evaluations developed during the review of circulating water system improvement candidates that accompanied the recent 4.5% power uprate of an existing large station with a closed cycle cooling system which utilizes a natural draft cooling tower. Presented in the paper are the capital costs and turbine performance improvements related to: air blanketing reduction by baffle plate additions to the condenser air coolers; minimizing costs of waterbox/bundle cleaning programs; cooling system performance monitoring enhancements; the prudency of tube staking after uprate; the benefits of a circulating water flow increase; better cooling tower hot water distribution; adding a layer of fill to the cooling tower; and finally the value of a helper tower. Considered too in this paper are the performance test surveys of both the condenser and cooling tower that identified the cause and/or performance deficiencies. The general principles to be discussed will be applicable to all sizes and types of power plant cooling systems. The paper however, will focus on the 1994-1995 case study of a 675,000 GPM closed cooling system with a 537 ft. counterflow natural draft cooling tower and a 670,000 sq. ft. six bundle single pass condenser which serves the six flow low pressure (LP) turbine of an 1100 MW nuclear plant. One example of the outcome of the program was an approximate 20% increase in condenser cleanliness from 55% to 75%. 9 refs., 7 figs.

  5. Assessment of water self-decontamination of NPP cooling water reservoirs

    Assessment of water self-decontamination of NPP cooling water reservoir (CWR) from radioactive materials using mathematical simulation method is conducted. In this case radiactive contaminant concentration and transport in water ecosystem were taken into account. Parameters of water self-decontamination and half-periods of separate radionuclides (137Cs, 60Co, 54Mn) from water for NPP CWR in the medium part of the USSR European territory are presented

  6. 76 FR 22173 - National Pollutant Discharge Elimination System-Cooling Water Intake Structures at Existing...

    2011-04-20

    ...) that addressed cooling water intake structures. 41 FR 17387 (April 26, 1976), see also the proposed... action on regulations governing cooling water intake structures at new facilities. See 66 FR 65255... Discharge Elimination System--Cooling Water Intake Structures at Existing Facilities and Phase I...

  7. 78 FR 64027 - Preoperational Testing of Emergency Core Cooling Systems for Pressurized-Water Reactors

    2013-10-25

    ... COMMISSION Preoperational Testing of Emergency Core Cooling Systems for Pressurized-Water Reactors AGENCY... Core Cooling Systems for Pressurized-Water Reactors.'' This RG is being revised to incorporate guidance... emergency core cooling systems (ECCSs) of pressurized water reactors (PWRs). This RG also describes...

  8. 77 FR 36014 - Initial Test Program of Emergency Core Cooling Systems for Boiling-Water Reactors

    2012-06-15

    ... COMMISSION Initial Test Program of Emergency Core Cooling Systems for Boiling-Water Reactors AGENCY: Nuclear...-1277, ``Initial Test Program of Emergency Core Cooling Systems for Boiling- Water Reactors.'' This... testing features of emergency core cooling systems (ECCSs) for boiling-water reactors (BWRs)....

  9. 78 FR 35330 - Initial Test Programs for Water-Cooled Nuclear Power Plants

    2013-06-12

    ... COMMISSION Initial Test Programs for Water-Cooled Nuclear Power Plants AGENCY: Nuclear Regulatory Commission... revision to Regulatory Guide (RG), 1.68, ``Initial Test Programs for Water-Cooled Nuclear Power Plants... Initial Test Programs (ITPs) for light water cooled nuclear power plants. ADDRESSES: Please refer...

  10. Development Project of Supercritical-water Cooled Power Reactor

    A Supercritical-water Cooled Power Reactor (SCPR) development project (Feb. 2001- Mar. 2005) is being performed by a joint team consisting of Japanese universities and nuclear venders with a national fund. The main objective of this project is to provide technical information essential to demonstration of SCPR technologies through concentrating three sub-themes: 'plant conceptual design', 'thermohydraulics', and 'material and water chemistry'. The target of the 'plant conceptual design sub-theme' is simplify the whole plant systems compared with the conventional LWRs while achieving high thermal efficiency of more than 40 % without sacrificing the level of safety. Under the 'thermohydraulics sub-theme', heat transfer characteristics of supercritical-water as a coolant of the SCPR are examined experimentally and analytically focusing on 'heat transfer deterioration'. The experiments are being performed using fron-22 for water at a fossil boiler test facility. The experimental results are being incorporated in LWR analytical tools together with an extended steam/R22 table. Under the 'material and water chemistry sub-theme', material candidates for fuel claddings and internals of the SCPR are being screened mainly through mechanical tests, corrosion tests, and simulated irradiation tests under the SCPR condition considering water chemistry. In particular, stress corrosion cracking sensitivity is being investigated as well as uniform corrosion and swelling characteristics. Influences of water chemistry on the corrosion product characteristics are also being examined to find preferable water condition as well as to develop rational water chemistry controlling methods. (authors)

  11. Characterization of radioactive nuclides in primary cooling water, 1

    The characterization of radioactive nuclides, especially fission products, in primary cooling water in a nuclear reactor is important with respect to FFD(Failed Fuel Detection), finding some other defects of the primary cooling systems and also improving them from the view point of radiation protection. The first step for that purpose will be to find out the principal sources of radioactive nuclides during the so-called normal operation period. A series of papers are ready to be published on these probrems. The present paper, Part I, describes the evaluation of fission number mainly due to uranium isotopes as functions of neutron fluence. As a result, it was concluded that contribution of 239Pu produced from 238U to the total fission number after prolonged irradiation becomes significant. It was also found out that the mode of time sequential change of neutron spectrum influences to a considerable extent the bilding up and burning up of 239Pu. Fissions taking place in the near surface of materials in and around reactor cores can be a principal source of fission fragments which recoil out of the material surfaces and are eroded out together with the matrix aluminum into the primary cooling water. (author)

  12. Chemical treatment of slime in industrial cooling water systems

    Sato, Noriyuki

    1987-07-01

    Chemical suppression test was made for slime produced in pipes of the industrial water cooling systems. The 3 month chemical slime treatment test in 1984 proved to be effective, and the test has been carried out since July, 1985. The objective was to suppress the generation of slime by decreasing the number of general bacteria by slime treatment agent (fungicide of chloride group). The number of bacteria in the supplied water was compared for the time and day of the week when samples were collected. It was found that there was no regular rule in the variation of the number of bacteria, with measured result of 30-10/sup 6/ variation range. From the variation in the number of bacteria and the sticking conditions of slime on the test board, it became clear that suppression was possible by drastically decreasing the bacteria number in cooling water in the early stage of chemical supply, followed by resupply of treatment agent in a week when the bacteria would be restored to its original amount by supplied water. However, the method is to suppress the slime generation, and is unable to stop the generation completely. (9 figs, 3 tabs)

  13. Corrosion issues in cooling water circuits of nuclear power plants

    Nuclear power plants cooling water circuits are required to refresh the vapour which is used to produce electricity. Raw oxygenated water, at temperature between ambient and 50 C is used for this purpose. It can lead to severe corrosion problems for many materials. This paper presents some of the main corrosion issues that were encountered in EDF cooling water circuits since their installation and explains how they were deal with. Corrosion problems were encountered on condenser tubes, condenser water boxes, pumping systems, and on different others devices. Cases involving carbon steels, low alloy steels, copper alloys and stainless steels are reported. The different forms of corrosion which were encountered are galvanic corrosion, erosion-corrosion, crevice corrosion, pitting corrosion and stress corrosion cracking. In some cases, bio-corrosion was also involved. In the different examples which are chosen, the different measures which were taken to cope with the issue are presented: material removing, cathodic protection, painting systems, procedure for out-of-work conservation and actions to ensure circuit properties are briefly discussed. (authors)

  14. Thermophysical properties of materials for water cooled reactors

    The IAEA Co-ordinated Research Programme (CRP) to establish a thermophysical properties data base for light and heavy water reactor materials was organized within the framework of the IAEA's International Working Group on Advanced Technologies for Water Cooled Reactors. The work within the CRP started in 1990. The objective of the CRP was to collect and systemaize a thermophysical properties data base for light and heavy water reactor materials under normal operating, transient and accident conditions. The important thermophysical properties include thermal conductivity, thermal diffusivity, specific heat capacity, enthalpy, thermal expansion and others. These properties as well as the oxidation of zirconium-based alloys, the thermophysical characteristics of high temperature concrete-core melt interaction and the mechanical properties of construction materials are presented in this report. It is hoped that this report will serve as a useful source of thermophysical properties data for water cooled reactor analyses. The properties data are maintained on the THERSYST system at the University of Stuttgart, Germany and are internationally available. Refs, figs, tabs

  15. Chemical cooling water treatment cuts corrosion rate 80%

    A study of the cooling water system at the Farley Nuclear Plant was made to establish the degree of corrosion and fouling that would take place with and without chemical treatment, and to determine the effect that increased cycles of concentration might have on fouling. It was established that a need for chemical treatment existed. The new cooling water treatment program yielded no fouling, a reduction in corrosion rates of 80%, and a decrease in water usage of about 10%. Experience showed that condenser fouling was not a problem, but that corrosion of mild steel piping was a possibility. Control of corrosion without causing any fouling problems, coupled with a desire to conserve water and reduce associated pumping costs, prompted studies to establish the current degree of corrosion and to determine the effect of increasing cycles of concentration of both corrosion and fouling, with and without chemical treatment. This paper covers a period of three years of plant operation. During the first year, the corrosion rates were measured and tests were made to evaluate the potential effect of increasing cycles of concentration

  16. Experimental validation of the simulation module of the water-cooled variable refrigerant flow system under cooling operation

    Li, Yue Ming; Wu, Jing Yi [Institute of Refrigeration and Cryogenics, Shanghai Jiao Tong University, Shanghai (China); Shiochi, Sumio [Daikin Industries, Ltd., 1304 Kanaoka-cho, Kita-ku, Sakai, Osaka 591-8511 (Japan)

    2010-05-15

    On the basis of EnergyPlus's codes, the catalogue and performance parameters from some related companies, a special simulation module for variable refrigerant flow system with a water-cooled condenser (water-cooled VRF) was developed and embedded in the software of EnergyPlus, the building energy simulation program. To evaluate the energy performance of the system and the accuracy of the simulation module, the measurement of the water-cooled VRF is built in Dalian, China. After simulation and comparison, some conclusions can be drawn. The mean of the absolute value of the daily error in the 9 days is 11.3% for cooling capacity while the one for compressor power is 15.7%. At the same time, the accuracy of the power simulation strongly depends on the accuracy of the cooling capacity simulation. (author)

  17. Ecotoxicological investigation in cooling water reservoirs of NPP and Dnepr cascade water reservoirs by using biotest

    Investigation data obtained during 1988-1992 have shown that NPP waste waters effected test-organisms: they induced changes in growth intensity and morphology of Spirodela polyrrhiza and high mortality of spawn and larvae of Salmo gairdneri as well as somatic mutations and mortality in Tradescantia SLC system. It indicates that toxic matters discharge to cooling reservoirs with NPP waste waters. Similar levels of toxicity and genotoxicity were found in Ignalina and Leningrad NPP waste waters, as well as in cooling reservoirs waters. The water of Dnepr cascade reservoirs was more eutrophic, toxic and genotoxic than the water of NPP cooling reservoirs. Water genotoxicity in the Dnepr cascade water reservoirs was equal to that of NPP waste waters. The Kiev reservoir water showed the highest genotoxicity.Bottom sediments of some biotopes of Kiev and Kachovsk water reservoirs were found to be the most genotoxic. The genotoxicity of these bottom sediments was equal to the Ignalina NPP EDS waste water treatment plant sludge, which commonly is utilized as hazardous waste. The use of test-organism system allows to estimate more precisely ecotoxicological situation in water reservoirs - to establish their eutrophic level, to identify radioactive and chemical water and bottom sediments pollution and to reveal synergetic effects of pollutant complex effect. 8 refs., 6 tabs

  18. Nuclear analysis of DEMO water-cooled blanket based on sub-critical water condition

    Highlights: ► For sub-critical water condition, the size of cooling loop would be more longer, for example, 2 m. ► Local TBR is related to the material fraction of breeders and multipliers, the beryllium is the dominant. ► Front area of blanket is dominant for blanket design and it would contribute the most of TBR comparing to the backside zones. - Abstract: For the water-cooled solid blanket of DEMO, the nuclear analysis was performed based on present cooling piping system. Especially, distributions of neutron load and temperature were calculated with Pn is 5 MW/m2. Furthermore, the local TBR was optimized by changing the material proportion for each Pn level (1–5 MW/m2). It was confirmed that the size of cooling loop for sub-critical water could be used as about 2000 × 450 mm and the cooling pipe diameter of D is 12 mm, d is 9 mm at v is 5.36 m/s. The pipe pitches would vary with Pn level which is related to the blanket structure design. Nuclear heat distribution is the base to decide the distribution of cooling pipe positions. It was found that the local TBR of blanket would be dropped down along with the Pn level rising which was mainly depended on the thickness of beryllium variation. Finally, the layout of cooling pipes for each level was obtained.

  19. Heat jettisoning from solar-thermal driven LiBr-H{sub 2}O absorber cooling units by pulsed spraying a dry cooler with water; Waermeabwurf aus einer solarthermisch getriebenen LiBr- H{sub 2}O Absorptionskaeltemaschine durch gepulstes Bespruehen eines Trockenkuehlers mit Wasser

    Gantenbein, P.; Helfenberger, R.; Frank, E.

    2010-07-01

    This short, illustrated final report discusses the removal of heat from solar-thermal driven LiBr-H{sub 2}O absorber cooling units by pulsed spraying a dry cooler with water. The reduction of electricity consumption for room cooling using conventional chillers is examined. Heat dissipation using open cooling towers and the disadvantages encountered are compared with heat dissipation using a dry cooler with heat-exchanger and fans. Additional evaporation cooling achieved by spraying the heat exchanger with water is described and discussed. The results of measurements made at the Institute for Solar Technology in Rapperswil, Switzerland, are presented and discussed.

  20. Water Purification

    1992-01-01

    Silver ionization water purification technology was originally developed for Apollo spacecraft. It was later used to cleanse swimming pools and has now been applied to industrial cooling towers and process coolers. Sensible Technologies, Inc. has added two other technologies to the system, which occupies only six square feet. It is manufactured in three capacities, and larger models are custom built on request. The system eliminates scale, corrosion, algae, bacteria and debris, and because of the NASA technology, viruses and waterborne bacteria are also destroyed. Applications include a General Motors cooling tower, amusement parks, ice manufacture and a closed-loop process cooling system.