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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. 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

  4. Use of nanofiltration to reduce cooling tower water consumption.

    Altman, Susan Jeanne; Ciferno, Jared

    2010-10-01

    Nanofiltration (NF) can effectively treat cooling-tower water to reduce water consumption and maximize water usage efficiency of thermoelectric power plants. A pilot is being run to verify theoretical calculations. A side stream of water from a 900 gpm cooling tower is being treated by NF with the permeate returning to the cooling tower and the concentrate being discharged. The membrane efficiency is as high as over 50%. Salt rejection ranges from 77-97% with higher rejection for divalent ions. The pilot has demonstrated a reduction of makeup water of almost 20% and a reduction of discharge of over 50%.

  5. Use of nanofiltration to reduce cooling tower water usage.

    Sanchez, Andres L.; Everett, Randy L.; Jensen, Richard Pearson; Cappelle, Malynda A.; Altman, Susan Jeanne

    2010-09-01

    Nanofiltration (NF) can effectively treat cooling-tower water to reduce water consumption and maximize water usage efficiency of thermoelectric power plants. A pilot is being run to verify theoretical calculations. A side stream of water from a 900 gpm cooling tower is being treated by NF with the permeate returning to the cooling tower and the concentrate being discharged. The membrane efficiency is as high as over 50%. Salt rejection ranges from 77-97% with higher rejection for divalent ions. The pilot has demonstrated a reduction of makeup water of almost 20% and a reduction of discharge of over 50%.

  6. Water distribution characteristics of spray nozzles in a cooling tower

    Vitkovic Pavol

    2015-01-01

    Water distribution characteristics of spray nozzles with spray plates used to distribute cooling water to the cooling fills in a cooling tower is one of the important parameters for the selection of nozzles. Water distribution characteristic describes the distribution of water from the axis of the nozzle along a fill. One of the parameters affecting the water distribution characteristic of the nozzle is airflow velocity of counter flow airstream. Water distribution characteristics are commonl...

  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. Water distribution characteristics of spray nozzles in a cooling tower

    Vitkovic, Pavol

    2015-05-01

    Water distribution characteristics of spray nozzles with spray plates used to distribute cooling water to the cooling fills in a cooling tower is one of the important parameters for the selection of nozzles. Water distribution characteristic describes the distribution of water from the axis of the nozzle along a fill. One of the parameters affecting the water distribution characteristic of the nozzle is airflow velocity of counter flow airstream. Water distribution characteristics are commonly measured using by a set of containers. The problem with this method of the measurement of characteristics is block of the airflow with collections of containers. Therefore, this work is using the visualization method.

  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. On hydraulics calculation of water distribution in cooling towers

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

  11. 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)

  12. 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.

  13. 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

  14. 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.)

  15. Heat transfer enhancement in a natural draft dry cooling tower under crosswind operation with heterogeneous water distribution

    Crosswind significantly decreases cooling efficiency of a natural draft dry cooling tower. The possibility of improving cooling efficiency with heterogeneous water distribution within the cooling tower radiators under crosswind condition is analysed. A CFD approach was used to model the flow field and heat transfer phenomena within the cooling tower and airflow surrounding the cooling tower. A mathematical model was developed from various CFD results. Having used a trained Genetic Algorithm with the result of mathematical model, the best water distribution was found among the others. Remodeling the best water distribution with the CFD approach showed that the highest enhancement of the heat transfer compared to the usual uniform water distribution.

  16. Heat transfer enhancement in a natural draft dry cooling tower under crosswind operation with heterogeneous water distribution

    Goodarzi, Mohsen; Amooie, Hossein [Bu-Ali Sina Univ., Hamedan (Iran, Islamic Republic of). Dept. of Mechanical Engineering

    2016-04-15

    Crosswind significantly decreases cooling efficiency of a natural draft dry cooling tower. The possibility of improving cooling efficiency with heterogeneous water distribution within the cooling tower radiators under crosswind condition is analysed. A CFD approach was used to model the flow field and heat transfer phenomena within the cooling tower and airflow surrounding the cooling tower. A mathematical model was developed from various CFD results. Having used a trained Genetic Algorithm with the result of mathematical model, the best water distribution was found among the others. Remodeling the best water distribution with the CFD approach showed that the highest enhancement of the heat transfer compared to the usual uniform water distribution.

  17. 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.

  18. 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.

  19. 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.

  20. 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)

  1. 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

  2. Self-optimizing Control of Cooling Tower for Efficient Operation of Chilled Water Systems

    Li, Xiao; Li, Yaoyu; Seem, John E.; Li, Pengfei

    2012-01-01

    The chilled-water systems, mainly consisting of electric chillers and cooling towers, are crucial for the ventilating and air conditioning systems in commercial buildings. Energy efficient operation of such systems is thus important for the energy saving of commercial buildings. This paper presents an extremum seeking control (ESC) scheme for energy efficient operation of the chilled-water system, and presents a Modelica based dynamic simulation model for demonstrating the effectiveness of th...

  3. 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.

  4. 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

  5. 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

  6. 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)

  7. 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)

  8. Molecular Characterization of Viable Legionella spp. in Cooling Tower Water Samples by Combined Use of Ethidium Monoazide and PCR

    Inoue, Hiroaki; Fujimura, Reiko; Agata, Kunio; Ohta, Hiroyuki

    2015-01-01

    Viable Legionella spp. in environmental water samples were characterized phylogenetically by a clone library analysis combining the use of ethidium monoazide and quantitative PCR. To examine the diversity of Legionella spp., six cooling tower water samples and three bath water samples were collected and analyzed. A total of 617 clones were analyzed for their 16S rRNA gene sequences and classified into 99 operational taxonomic units (OTUs). The majority of OTUs were not clustered with currently described Legionella spp., suggesting the wide diversity of not-yet-cultured Legionella groups harbored in cooling tower water environments. PMID:25736979

  9. 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

  10. Predicting cooling tower plume dispersion

    An assessment of the effects of visible cooling tower plumes on the local environment can be a necessary part of any proposal for a new large industrial process. Predictions of the dispersion of plumes from cooling towers are based on methods developed for chimney emissions. However, the kinds of criteria used to judge the acceptability of cooling tower plumes are different from those used for stack plumes. The frequency of long elevated plumes and the frequency of ground fogging are the two main issues. It is shown that events associated with significant plumes visibility are dependent both on the operating characteristics of the tower and on the occurrence of certain meteorological conditions. The dependence on atmospheric conditions is shown to be fairly complex and simple performance criteria based on the exit conditions from the tower are not sufficient for assessments. (author)

  11. Design and characterisation of fluidised bed cooling towers

    Mbua Egbe, Louis

    2001-01-01

    This thesis discusses the operating characteristics and design of fluidised bed cooling towers (FBCT), which may be used to cool hot water for industrial purposes. Limited data exist for such a three-phase fluidised bed acting as a cooling tower. This motivated some early workers to investigate its usefulness in cooling tower applications and they showed that the FBCT produces heat and mass transfer rates much higher than in conventional fixed-bed towers. Despite this advantage, the FBCT has ...

  12. 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.

  13. 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

  14. 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.

  15. Application of Response Surface Methodology (RSM) for Optimization of Operating Parameters and Performance Evaluation of Cooling Tower Cold Water Temperature

    Ramkumar RAMAKRISHNAN; Ragupathy ARUMUGAM

    2012-01-01

    The performance of a cooling tower was analyzed with various operating parameters tofind the minimum cold water temperature. In this study, optimization of operating parameters wasinvestigated. An experimental design was carried out based on central composite design (CCD) withresponse surface methodology (RSM). This paper presents optimum operating parameters and theminimum cold water temperature using the RSM method. The RSM was used to evaluate the effectsof operating variables and their in...

  16. 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.)

  17. 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

  18. 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

  19. 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.

  20. IMPROVEMENT OF SYSTEMS OF TECHNICAL WATER SUPPLY WITH COOLING TOWERS FOR HEAT POWER PLANTS TECHNICAL AND ECONOMIC INDICATORS PERFECTION. Part 2

    Yu. A. Zenovich-Leshkevich-Olpinskiy

    2016-01-01

    Full Text Available The method of calculation of economic efficiency that can be universal and is suitable for feasibility study of modernization of irrigation and water distribution system of cooling towers has been developed. The method takes into account the effect of lower pressure exhaust steam in the condenser by lowering the temperature of the cooling water outlet of a cooling tower that aims at improvement of technical and economic indicators of heat power plants. The practical results of the modernization of irrigation and water distribution system of a cooling tower are presented. As a result, the application of new irrigation and water distribution systems of cooling towers will make it possible to increase the cooling efficiency by more than 4 оС and, therefore, to obtain the fuel savings by improving the vacuum in the turbine condensers. In addition, the available capacity of CHP in the summer period is increased. The results of the work, the experience of modernization of irrigation and water distribution systems of the Gomel CHP-2 cooling towers system, as well as the and methods of calculating of its efficiency can be disseminated for upgrading similar facilities at the power plants of the Belarusian energy system. Some measures are prosed to improve recycling systems, cooling towers and their structures; such measures might significantly improve the reliability and efficiency of technical water supply systems of heat power plants.

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

    Qin, Tian; Zhou, Haijian; Ren, Hongyu; GUAN, HONG; Li, Machao; Zhu, Bingqing; Shao, Zhujun

    2014-01-01

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

  2. Physical parameters of effluent from nuclear power station cooling towers

    Physical parameters of the effluent dispersed from the wet cooling towers, i.e. mixture of the warm moist air with the entrained droplets are analysed. Understanding of the effluent physical parameters at the exit of cooling tower is important for prediction of the effluent dispersion in the environment. Mass and droplet diameter distributors of the drifted cooling water are measured in situ and also, drift eliminators are characterised experimentally. A new numerical method for heat and mass transfer evaluation in the cooling tower packing (fill) was developed, that leads to more accurate prediction for outlet air parameters in relation of plant power rate, cooling tower characteristics and atmospheric conditions. (author)

  3. PERFORMANCE ANALYSIS OF MECHANICAL DRAFT COOLING TOWER

    Lee, S; Alfred Garrett, A; James02 Bollinger, J; Larry Koffman, L

    2009-02-10

    Industrial processes use mechanical draft cooling towers (MDCT's) to dissipate waste heat by transferring heat from water to air via evaporative cooling, which causes air humidification. The Savannah River Site (SRS) has cross-flow and counter-current MDCT's consisting of four independent compartments called cells. Each cell has its own fan to help maximize heat transfer between ambient air and circulated water. The primary objective of the work is to simulate the cooling tower performance for the counter-current cooling tower and to conduct a parametric study under different fan speeds and ambient air conditions. The Savannah River National Laboratory (SRNL) developed a computational fluid dynamics (CFD) model and performed the benchmarking analysis against the integral measurement results to accomplish the objective. The model uses three-dimensional steady-state momentum, continuity equations, air-vapor species balance equation, and two-equation turbulence as the basic governing equations. It was assumed that vapor phase is always transported by the continuous air phase with no slip velocity. In this case, water droplet component was considered as discrete phase for the interfacial heat and mass transfer via Lagrangian approach. Thus, the air-vapor mixture model with discrete water droplet phase is used for the analysis. A series of parametric calculations was performed to investigate the impact of wind speeds and ambient conditions on the thermal performance of the cooling tower when fans were operating and when they were turned off. The model was also benchmarked against the literature data and the SRS integral test results for key parameters such as air temperature and humidity at the tower exit and water temperature for given ambient conditions. Detailed results will be published here.

  4. 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)

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

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

  6. Plant Vogtle cooling tower studies

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

  7. Plant Vogtle cooling tower studies

    O' Steen, L.

    2000-01-26

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

  8. IMPROVEMENT OF SYSTEMS OF TECHNICAL WATER SUPPLY WITH COOLING TOWERS FOR STEAM POWER PLANTS TECHNICAL AND ECONOMIC INDICATORS PERFECTION. Part 1

    Yu. A. Zenovich-Leshkevich-Olpinskiy

    2016-01-01

    Full Text Available In order to reduce the temperature of cooling water and increase the efficiency of use of power resources the main directions of modernization of systems of technical water supply with cooling towers at steam power plants are presented. The problems of operation of irrigation systems and water distribution systems of cooling towers are reviewed. The design of heat and mass transfer devices, their shortcomings and the impact on the cooling ability of the cooling tower are also under analysis. The use of droplet heat and mass transfer device based on the lattice polypropylene virtually eliminates the shortcomings of the film and droplet-film heat and mass transfer devices of the cooling tower, increasing lifetime, and improving the reliability and efficiency of the operation of the main equipment of thermal power plants. The design of the water distribution devices of cooling towers is also considered. It is noted that the most effective are water-spattering low-pressure nozzles made of polypropylene that provides uniform dispersion of water and are of a high reliability and durability.

  9. 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.

  10. 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

  11. Use of cooling tower blow down in ethanol fermentation.

    Rajagopalan, N; Singh, V; Panno, B; Wilcoxon, M

    2010-01-01

    Reducing water consumption in bioethanol production conserves an increasingly scarce natural resource, lowers production costs, and minimizes effluent management issues. The suitability of cooling tower blow down water for reuse in fermentation was investigated as a means to lower water consumption. Extensive chemical characterization of the blow down water revealed low concentrations of toxic elements and total dissolved solids. Fermentation carried out with cooling tower blow down water resulted in similar levels of ethanol and residual glucose as a control study using deionized water. The study noted good tolerance by yeast to the specific scale and corrosion inhibitors found in the cooling tower blow down water. This research indicates that, under appropriate conditions, reuse of blow down water from cooling towers in fermentation is feasible. PMID:21076211

  12. 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.)

  13. Observed cooling tower plume characteristics

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

  14. Cooling towers - terms and definitions

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

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

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

    2010-12-01

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

  16. Noise emissions of cooling towers; Geraeuschemissionen von Kuehltuermen

    Hinkelmann, Dirk [Mueller-BBM GmbH, Gelsenkirchen (Germany)

    2013-09-01

    Cooling towers are often large structures with high sound emission. The impact of water drops on the water surface in the collecting basin leads to the generation of middle- and high-frequency noise that is emitted via the air intake opening and the outlet. In forced-draft cooling towers, additional noise is generated by drives and fans. The sound emissions can be predicted by means of empirical calculation models. In this way, noise control measures can be taken into account already at an early phase of planning. Different, proven measures for reduction of sound emissions are taken depending on cooling tower design. Regulations on noise acceptance testing for cooling towers are given in various standards. (orig.)

  17. 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

  18. Rapid quantification of viable Legionella in nuclear cooling tower waters using filter cultivation, fluorescent in situ hybridization, and solid phase cytometry

    Baudart, Julia; Guillaume, C.; Mercier, A.; Lebaron, P.; Binet, M.

    2015-01-01

    To develop a rapid and sensitive method to quantify viable Legionella spp. in cooling tower water samples. A rapid, culture-based method capable of quantifying as few as 600 Legionella microcolonies per litre within 2 days in industrial waters was developed. The method combines a short cultivation step of microcolonies on GVPC agar plate, specific detection of Legionella cells by a fluorescent in situ hybridization (FISH) approach, and a sensitive enumeration using a solid-phase cytometer. Fo...

  19. 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.)

  20. Universal Engineering Model for Cooling Towers

    Mohd Arif

    2015-05-01

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

  1. 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

  2. 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.

  3. Corrosion control studies in a mini cooling tower

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

  4. Water and chemical savings in cooling towers by using membrane capacitive deionization

    Limpt, van B.; Wal, van der A.

    2014-01-01

    Membrane capacitive deionization (MCDI) is a water desalination technology based on applying a voltage difference between two oppositely placed porous carbon electrodes. In front of each electrode, an ion exchange membrane is positioned, and between them, a spacer is situated, which transports the w

  5. Sensitivity Studies of a Low Temperature Low Approach Direct Cooling Tower for Building Radiant Cooling Systems

    Nasrabadi, Mehdi; Finn, Donal; Costelloe, Ben

    2012-01-01

    Recent interest in cooling towers as a mechanism for producing chilled water, together with the evolution of radiant cooling, have prompted a review of evaporative cooling in temperate maritime climates. The thermal efficiency of such systems is a key parameter, as a measure of the degree to which the system has succeeded in exploiting the cooling potential of the ambient air. The feasibility of this concept depends largely however, on achieving low approach water temperatures within an appro...

  6. Indiana State University Graduates to Advanced Plastic Cooling Towers

    Sullivan, Ed

    2012-01-01

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

  7. 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

  8. 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.

  9. 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.

  10. Cooling tower irrigator layout with allowances for non-uniformity of the airflow velocity field

    Pushnov, A. S.; Ryabushenko, A. S.

    2016-07-01

    This article covers the results of analysis of aerodynamic processes in the cooling tower irrigator and provides the approaches to optimal layout of preformed packing blocks (of the irrigator) developed based on these results. The analysis of the airflow velocity field in the cooling towers shows that the irrigation space can be broken down into the following zones: the peripheral zone of the cooling tower near the airblast windows, the zone near the cooling tower center, and the intermediate zone. Furthermore, the highest level of nonuniformity of the airflow velocity field in cooling towers is in the zone adjoining the tower's airblast windows. The proposed concept of the cooling tower irrigator's layout is made with allowances for the airflow velocity field characteristics in the cross-section of the irrigation space of the cooling tower. Based on this concept, we suggest that higher irrigator blocks should be placed in the zone of increased airflow consumption, which provides the possibility to enhance the hydraulic resistance and, respectively, decrease the gas flow velocity as well as to boost the efficiency of chilling the circulating water in the cooling tower. For this purpose, additional irrigator blocks can be of the same design as the main irrigator. As an option, it is possible to use blocks of the geometry and design other than the main irrigator block in the cooling tower.

  11. Review of cooling tower drift deposition models

    Chen, N.C.J.

    1977-05-04

    The behavior, basic assumptions, and limitations of ten different models for calculating the drift deposition rate from wet cooling towers are reviewed and then their predicted results for such deposition with a common set of input parameters are compared. The predicted maximum deposition differs among the models by two orders of magnitude with a wide range in peak location. Comments and suggestions to improve the models are included.

  12. 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

  13. 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

  14. An Analysis Method of Cooling Tower Supplemental Water Cost%冷却塔补水成本的一种分析方法

    唐毅

    2014-01-01

    The paper proposes the idea of converting the cooling tower supplement water of central air conditioning system to the corresponding electricity energy cost , as well as the concept of electrical equivalent price in water sup-plement cost.According to research , it is found that the water prices among different cities in China are quite dis-tinct, which suggests that the operation cost of cooling tower needs to be fully considered in air conditioning system selection.%本文提出了将集中空调系统冷却塔补水量换算成同等电费的电量来参与空调系统运行能耗成本计算的思路,提出了水的电当量概念。通过对比全国部分城市的水价,发现各城市之间水价差异大,认为在选择空调方案时,应充分重视冷却塔补水的运行成本。

  15. 冷却塔补水成本的一种分析方法%An Analysis Method of Cooling Tower Supplemental Water Cost

    唐毅

    2014-01-01

    The paper proposes the idea of converting the cooling tower supplement water of central air conditioning system to the corresponding electricity energy cost , as well as the concept of electrical equivalent price in water sup-plement cost.According to research , it is found that the water prices among different cities in China are quite dis-tinct, which suggests that the operation cost of cooling tower needs to be fully considered in air conditioning system selection.%本文提出了将集中空调系统冷却塔补水量换算成同等电费的电量来参与空调系统运行能耗成本计算的思路,提出了水的电当量概念。通过对比全国部分城市的水价,发现各城市之间水价差异大,认为在选择空调方案时,应充分重视冷却塔补水的运行成本。

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

    Laković 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.

  17. CFD MODELING ANALYSIS OF MECHANICAL DRAFT COOLING TOWER

    Lee, S; Alfred Garrett, A; James02 Bollinger, J; Larry Koffman, L

    2008-03-03

    Industrial processes use mechanical draft cooling towers (MDCT's) to dissipate waste heat by transferring heat from water to air via evaporative cooling, which causes air humidification. The Savannah River Site (SRS) has a MDCT consisting of four independent compartments called cells. Each cell has its own fan to help maximize heat transfer between ambient air and circulated water. The primary objective of the work is to conduct a parametric study for cooling tower performance under different fan speeds and ambient air conditions. The Savannah River National Laboratory (SRNL) developed a computational fluid dynamics (CFD) model to achieve the objective. The model uses three-dimensional steady-state momentum, continuity equations, air-vapor species balance equation, and two-equation turbulence as the basic governing equations. It was assumed that vapor phase is always transported by the continuous air phase with no slip velocity. In this case, water droplet component was considered as discrete phase for the interfacial heat and mass transfer via Lagrangian approach. Thus, the air-vapor mixture model with discrete water droplet phase is used for the analysis. A series of the modeling calculations was performed to investigate the impact of ambient and operating conditions on the thermal performance of the cooling tower when fans were operating and when they were turned off. The model was benchmarked against the literature data and the SRS test results for key parameters such as air temperature and humidity at the tower exit and water temperature for given ambient conditions. Detailed results will be presented here.

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

    Lucas, M.; Martinez, P.J. [Departamento Ingenieria de Sistemas Industriales, Universidad Miguel Hernandez, Avda. de la Universidad, s/n, 03202 Elche (Spain); Viedma, A. [Departamento de Ingenieria Termica y de Fluidos, Universidad Politecnica de Cartagena (Campus Muralla del Mar), Dr. Fleming, s/n, 30202 Cartagena (Spain)

    2009-03-15

    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%. (author)

  1. 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%

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

    Bharathan, Desikan; Hassani, A. Vahab

    1997-01-01

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

  4. Effect of solar radiation on the performance of cross flow wet cooling tower in hot climate of Iran

    Banooni, Salem; Chitsazan, Ali

    2016-01-01

    In some cities such as Ahvaz-Iran, the solar radiation is very high and the annual-mean-daily of the global solar radiation is about 17.33 MJ m2 d-1. Solar radiation as an external heat source seems to affect the thermal performance of the cooling towers. Usually, in modeling cooling tower, the effects of solar radiation are ignored. To investigate the effect of sunshade on the performance and modeling of the cooling tower, the experiments were conducted in two different states, cooling towers with and without sunshade. In this study, the Merkel's approach and finite difference technique are used to predict the thermal behavior of cross flow wet cooling tower without sunshade and the results are compared with the data obtained from the cooling towers with and without sunshade. Results showed that the sunshade is very efficient and it reduced the outlet water temperature, the approach and the water exergy of the cooling tower up to 1.2 °C, 15 and 1.1 %, respectively and increased the range and the efficiency of the cooling tower up to 29 and 37 %, respectively. Also, the sunshade decreased the error between the experimental data of the cooling tower with sunshade and the modeling results of the cooling tower without sunshade 1.85 % in average.

  5. 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.)

  6. 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.)

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

    Iñigo-Golfín, J

    2001-01-01

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

  8. 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

  9. 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

  10. Evaluation of IR technology applied to cooling tower performance

    MacNamara, Neal A.; Zayicek, Paul A.

    1999-03-01

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

  11. Environmental Impacts from the Operation of Cooling Towers at SRP

    Smith, F.G. III

    2001-06-26

    An assessment has been made of the environmental effects that would occur from the operation of cooling towers at the SRP reactors. A more realistic numerical model of the cooling tower plume has been used to reassess the environmental impacts. The following effects were considered: (1) the occurrence of fog and ice and their impact on nearby structures, (2) drift and salt deposition from the plume, (3) the length and height of the visible plume, and (4) the possible dose from tritium.

  12. 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.

  13. 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

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

    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 (∼47%), wood (∼38%) and asbestos transite (∼14%). The remaining ∼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

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

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

  16. 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.

  17. Comparison of cooling ability of asbestic-cement and mesh sprinkler of cooling tower

    Кравченко, Владимир Петрович; Морозов, Евгений Николаевич; Галацан, Марк Петрович

    2012-01-01

    The technological calculation of a cooling tower with a pass checker from the asbestos-cement and modern reticulated checker from a polyethylene is executed. Got results, allow executing the feasibility study of reconstruction of cooling tower with pass checker substituting by a modern construction

  18. 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.

  19. Legionella safety in cooling towers; Legionellaveiligheid in koeltorens

    Kordes, B. [Kordes Advies, (Netherlands); De Bok, F. [KBBL Wijhe, (Netherlands); De Zeeuw, L. [Holland Environment Group, (Netherlands); Settels, P. [Safety, Health Services and Ergonomics, ING, (Netherlands); Oesterholt, F.; Wullings, B. [KWR Watercycle Research Institute, (Netherlands); Guiot, P. [Tevan, Gorinchem (Netherlands); Brands, R. [Cumulus Nederland, Cuijk (Netherlands); Nuijten, O. [Kennisinstituut ISSO, Rotterdam (Netherlands); Wijne, R. [Beer advocaten, Amsterdam (Netherlands)

    2010-04-15

    In 9 articles attention is paid to several aspects with regard to Legionella in cooling towers: representative sampling, the use of copper and silver ionization or hydrogen peroxide to prevent Legionella growth and biofilms, the use of a zero-tolerance model to control a cooling tower installation, detection of DNA of Legionella Pneumophila, legionella safety in air conditioners, the model Legionella risk analysis and control of cooling tower installations, legislation and regulations for the control of cooling tower installations with regard to the Dutch Occupational Health and Safety Act ('Arbo-wet'), and an article about a lawsuit for victims of a Legionella outbreak, caused by careless owners of a cooling tower in Amsterdam, Netherlands. [Dutch] In 9 artikelen wordt in deze aflevering aandacht besteed aan verschillende aspecten m.b.t. Legionella in koeltorens: representatieve monstername, de toepassing van koper en zilver-ionisatie of waterstofperoxide om de groei van Legionella en biofilms te voorkomen, het gebruik van een zero-tolerance model om een koeltoren installatie te controleren, detectie van DNA van Legionella Pneumophila, Legionella veiligheid in luchtbehandelingsinstallaties, het model Legionella risicoanalyse en beheersplan voor koeltoreninstallaties, de rol van de Arbo-wet, en een artikel over een rechtszaak voor slachtoffers van Legionella door onzorgvuldig beheer van een koeltoren in Amsterdam.

  20. 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)

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

    Laković Mirjana S.; Laković Slobodan V.; Banjac Miloš J.

    2012-01-01

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

  2. 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

  3. Circulating Water Cooling Tower of Cell Transformation Ation in Sodium Metal Production%金属钠生产中电解槽循环水冷却塔改造

    王守霞; 王广鹏

    2014-01-01

    内蒙古兰太实业股份有限公司1万t/a金属钠生产所需电解槽必须采用冷却水进行循环冷却降温,为了防止循环水管道腐蚀,确保电解槽的安全稳定运行,对循环水的水质要求较高,需要采用纯水.原有冷却塔为旧式敞开式填料冷却塔,设备老化严重,跑水量大,增加了纯水制造成本,造成水资源浪费,且敞开式的塔由于周边风沙大造成水质严重污染,泥沙经常堵塞电解槽循环水管道,也增加了工人劳动强度及清理费用.针对这一系列问题,公司建议将开式冷却塔进行改造,采用闭式冷却塔,使循环水在冷却塔换热管内循环,这样不仅避免了纯水的浪费,且大大降低了纯水的制造成本,还防止泥沙及其他杂质进入循环水系统污染水质,解决了管道堵塞的问题,降低了人员劳动强度和清理成本.%10 000 t/a metal sodium must use circulating cooling water to generate the required circulating cool for cell in Inner Mongolia Lantai Industrial Co.,Ltd..In order to prevent the circulating water pipeline corrosion,to ensure safe and stable operation of the cell,the circulating water quality required higher,which need pure water.Original cooling tower was the old open packing cooling tower,which had problem of equipment aging seriously,running large water,increasing of water production costs and resulting in waste of water resources.The big surrounding sand caused serious water pollution of the open tower.Sediment often blocked electrolyzer recycled water pipeline and also increased labor intensity and clean-up costs.For this series of questions,the company proposed to renovate the open cooling tower with closed cooling tower.The circulating water was in the cooling tower circulating tubes,which not only avoided the water waste and greatly reduced the pure water manufacturing costs,but also prevented sediment and other contaminants from entering the contaminated water circulating water system to solve

  4. 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

  5. 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

  6. 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.

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

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

  8. 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)

  9. 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.

  10. Boundary working regimes of condense-type turbine K-200-130 in case of using wet and dry cooling towers

    Usage of wet cooling towers is connected with utilisation of considerable quantities of water with aim to cover the evaporation looses. The usage of di-y cooling towers in energy power stations in cases with modified temperate continental climate, water supply problems and ecological limitations can be applicable. Working data Of cooling towers in these climate conditions are estimated through parametric analyse using appropriate mathematical modelling of working processes. (Author)

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

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

    1976-09-01

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

  12. Cooling tower improvement cuts costs at Illinois Power

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

  13. 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

  14. 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

  15. 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

  16. Brief Discussion on the Application of Spray Cooling Tower with Packing in the Circulation Water System in Our Company%浅谈无填料喷雾冷却塔在我公司循环水系统中的运用

    刘宝峰; 顾收红

    2012-01-01

    This paper analyzes the application feasibility of spray cooling tower with packing in the circulation water system from the comparison of the structure,the principle and all kinds of conditions in the process of using cooling tower with packing and spray cooling tower without packing.It is hoped that cooling tower without packing be widely used in the salt making industry.%通过阐述填料冷却塔与无填料喷雾冷却塔的结构、原理以及两者在使用过程中的各种情况比较出发,深入浅出的分析了无填料喷雾冷却塔在循环水系统运用的可行性,并希望无填料塔在制盐行业中能够广泛应用。

  17. 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.

  18. 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.

  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. 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.

  1. Effects of wet cooling towers on weather and climate

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

  2. 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

  3. 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.

  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. The chlorination of cooling water

    After reviewing the means of fighting biological pollution of cooling water circuits in nuclear power stations, the authors describe the chlorination treatment methods used by EDF. This deals with the massive shock chlorination of the cooling towers and the continuous low-level chlorination of coastal nuclear power stations. In both areas, the Research and Development Board of EDF has carried out and encouraged research with the aim of improving circuit protection, while still protecting the aquatic eco-system against damage that might be caused by waste chlorinated water

  6. 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

  7. Leaching of asbestos-cement cooling-tower fill. Final report

    Anderson, C.N.; Stone, R.W.

    1981-04-01

    Cooling-tower fill is sometimes made of asbestos cement. Asbestos-cement fill has frequently been damaged by leaching and mechanical problems. This leaching was investigated. Previous studies of asbestos-cement water pipe and cooling-tower fill are summarized. Five plants were visited, and 43 others were contacted by telephone. Water and fill samples were collected and analyzed. About half of the cooling towers with asbestos-cement fill have experienced significant deterioration. To control leaching, water should not be undersaturated with respect to calcium carbonate. The Langelier saturation index is a useful tool for controlling blowdown rates and chemical feed. However, because this index does not allow for all of the relevant factors, it is not possible to recommend values that are suitable for all plants. If no scale inhibitors are used, the index should be kept as high as possible without causing calcium carbonate scale. If scale inhibitors are used, overdosing should be avoided. Asbestos-cement fill should be used only if the cooling-water chemistry can be well controlled. Specifications for asbestos-cement fill can be improved. Other design features, operating practices, and research are suggested.

  8. Pilot-scale treatment of gasification wastewater and reuse in a cooling tower

    Willson, W.G.; Mayer, G.G.; Hendrikson, J.G.; Winton, S.L.

    1985-04-01

    The University of North Dakota Energy Research Center has operated a 910 kg/hr, oxygen-blown fixed-bed gasifier to produce lignite-derived effluents for characterization, treatment, and reuse studies. Reuse of waste water in a cooling tower was investigated to define environmental and process effects as a function of pretreatment. The gasification wastewater was pretreated in pilot wastewater treatement units which simulate available technology. During the first phase of the program, wastewater was pretreated by solvent extraction and steam stripping to produce phenol and ammonia concentrations comparable to those expected at the Great Plains Gasification Associates plant. This pretreated wastewater was concentrated in a cooling tower to 10 cycles of concentration. No biocides or corrosion inhibitors were added. Severe fouling of heat exchange surfaces and high corrosion rates of carbon steel were encountered. Over 90% of the phenol entering the cooling tower was found to be stripped into the cooling tower exhaust air stream. The high levels of organics remaining in this minimally treated wastewater suggested that further biological treatment and possibly polishing by carbon adsorption would be necessary to prepare a satisfactory feed. In the second phase of the program, the SGL was further treated in an activated sludge process followed by granular activated carbon adsorption. Biotreatment removed 96% of the BOD with a three-day retention time while obtaining satisfactory sludge settling rates in spite of varied influent concentrations. Biorefractory materials were adsorbed on GAC to reach an effuent COD level of 150 mg/l. This upgrading was sufficient to reduce organic emissions from the cooling tower, but corrosion rates were higher than in the previous test, again showing the necessity for corrosion inhibitors. 8 figs., 3 tabs.

  9. 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

  10. 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.)

  11. 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.

  12. Development of a wet cooling tower with small capacity for the use in solar cooling systems; Entwicklung eines offenen Nasskuehlturms kleiner Leistungsklasse. Fuer den Einsatz in Systemen zum Solaren Kuehlen

    Wiegand, E.; Kohlenbach, P. [Phoenix SonnenWaerme AG, Berlin (Germany); Kuehn, A.; Petersen, S.; Ziegler, F. [TU Berlin (Germany). Inst. fuer Energietechnik

    2005-10-01

    The following article presents the development of a small-capacity wet cooling tower optimized for the use in small-scale solar cooling systems. The cooling tower has a cooling capacity of 23 kW{sub th} at a wet bulb temperature of 21 C, water inlet/outlet temperatures of 35/27 C and a water flow rate of 2.5 m{sup 3}/h. The power consumption at these operation conditions is 190 W{sub el}. Compared to existing cooling tower models a reduction of volume, footprint and maximum power consumption could be achieved. (orig.)

  13. Fire analog: a comparison between fire plumes and energy center cooling tower plumes

    Thermal plumes or convection columns associated with large fires have been compared to thermal plumes from cooling tower systems to evaluate the fire analog concept. Energy release rate of mass fires is generally larger than that of single or small groups of cooling towers but may be comparable to proposed large energy centers. However, siginficant physical differences exist between cooling tower and fire plumes. Cooling tower plumes are usually dominated by ambient wind and turbulence conditions. Fire plumes, depending on fire intensity and area, can transform into free convection energy systems resulting in convective columns, strong inflow and updrafts, turbulence and concentrated vortices. Since these characteristics have not been observed with cooling tower plumes to date, the fire analog concept is questionable at this time. Additional research is needed on fire and cooling tower plumes

  14. Physical quantities related to measurement campaigns for cooling towers

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

  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. 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

  17. 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)

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

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

  19. Two-phase Euler-Lagrange CFD simulation of evaporative cooling in a Wind Tower

    Saffari, Hamid; Hosseinnia, S.M. [Department of Mechanical Engineering, Iran University of Science and Technology, Narmak, Tehran 16844 (Iran)

    2009-09-15

    A new design of Wind Tower is investigated numerically under different structural parameters and environmental conditions. The new design is some wetted columns, consisting of wetted curtains hung in the tower column, which are modeled as surfaces that inject droplets of water with very low speed. The CFD open source package - Open FOAM - is used. The current three-dimensional CFD simulation has adopted both the Eulerian approach for the air phase and the Lagrangian approach for the water phase. The effects of water droplet diameter and water droplet temperature on the thermal performance of the Wind Tower are investigated at specific inlet air velocity and relative humidity and height of wetted columns. Also, the effects of wind velocity, temperature, and relative humidity inlet to Wind Tower are studied. Changing the height of the wetted columns and its effect on the evaporative cooling in other specific parameters is studied. The results obtained from the present CFD study are compared with the analytical data taken from the literature and a good agreement is observed. As a result, the height of 10 m of wetted columns decreases 12 K of the ambient air temperature and increases 22% of its relative humidity. (author)

  20. 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.

  1. 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.)

  2. 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

  3. 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

  4. 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.

  5. Rationalization of cooling water consumption in extraction system B-811 LSV

    Budžaki, Sandra; Čačić, F.; Miljić, G.

    2014-01-01

    Water (drinkable) is vital natural resource, and during the last few decades it is imperative to reduce its needless consumption. Extraction devices are known for their significant cooling water consumption and laboratory scale devices mainly use drinkable water. Aim of this paper was rationalization of cooling water consumption during extractions in universal extraction system B-811 LSV by recirculating cooling water trough cooling tower. In order to obtain the data for cooling tower design,...

  6. Fire analog: a comparison between fire plumes and energy center cooling tower plumes

    Orgill, M.M.

    1977-10-01

    Thermal plumes or convection columns associated with large fires are compared to thermal plumes from cooling towers and proposed energy centers to evaluate the fire analog concept. Energy release rates of mass fires are generally larger than for single or small groups of cooling towers but are comparable to proposed large energy centers. However, significant physical differences exist between cooling tower plumes and fire plumes. Cooling tower plumes are generally dominated by ambient wind, stability and turbulence conditions. Fire plumes, depending on burning rates and other factors, can transform into convective columns which may cause the fire behavior to become more violent. This transformation can cause strong inflow winds and updrafts, turbulence and concentrated vortices. Intense convective columns may interact with ambient winds to create significant downwind effects such as wakes and Karman vortex streets. These characteristics have not been observed with cooling tower plumes to date. The differences in physical characteristics between cooling tower and fire plumes makes the fire analog concept very questionable even though the approximate energy requirements appear to be satisfied in case of large energy centers. Additional research is suggested in studying the upper-level plume characteristics of small experimental fires so this information can be correlated with similar data from cooling towers. Numerical simulation of fires and proposed multiple cooling tower systems could also provide comparative data.

  7. Costs and cost algorithms for dry cooling tower systems

    Ard, P.A.; Henager, C.H.; Pratt, D.R.; Wiles, L.E.

    1976-09-01

    Costs were obtained and cast models prepared for the major components beyond the turbine exhaust flange of a dry cooling system using either water or ammonia as the intermediate heat exchange fluid. (LCL)

  8. Fire analog: a comparison between fire plumes and energy center cooling tower plumes

    Past studies on the waste heat from thermal power plant cooling towers and proposed energy parks suggest that the dissipation of this waste energy may result in significant meteorological effects. Preliminary calculations have shown that the rate of atmospheric dissipation of the waste energy from groupings of cooling towers is approximately equal to that by geophysical phenomena such as thunderstorms, volcanoes, and large fires. Cumulus clouds and convective vortices often result from these natural energy releases. One of the geophysical analogs, the large fire, is evaluated in terms of how good a physical analog it is to cooling towers or groups of cooling towers. The literature on experimental and wild fires was reviewed in relation to how fire thermal plume characteristics may be typical of a thermal plume from cooling towers

  9. Legionnaires' Disease Outbreak at a Long-Term Care Facility Caused by a Cooling Tower Using an Automated Disinfection System--Ohio, 2013.

    Quinn, Celia; Demirjian, Alicia; Watkins, Louise Francois; Tomczyk, Sara; Lucas, Claressa; Brown, Ellen; Kozak-Muiznieks, Natalia; Benitez, Alvaro; Garrison, Laurel E; Kunz, Jasen; Brewer, Scott; Eitniear, Samantha; DiOrio, Mary

    2015-12-01

    On July 9, 2013, an outbreak of Legionnaires' disease (LD) was identified at Long-Term Care Facility A in central Ohio. This article describes the investigation of the outbreak and identification of the outbreak source, a cooling tower using an automated biocide delivery system. In total, 39 outbreak LD cases were identified; among these, six patients died. Water samples from a cooling tower were positive for Legionella pneumophila serogroup 1, reactive to monoclonal antibody 2, with matching sequence type to a patient isolate. An electronic control system turned off cooling tower pumps during low-demand periods, preventing delivery of disinfectant by a timed-release system, and leading to amplification of Legionella in the cooling tower. Guidelines for tower maintenance should address optimal disinfection when using automated systems. PMID:26738313

  10. 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.

  11. 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.

  12. Advanced dry and dry--wet cooling towers

    Johnson, B. M.

    1977-09-01

    Although progressive restrictions on the use of fresh water for power plant cooling and the growing use of dry cooling is anticipated in many regions of the country, the transition to this form of cooling will occur slowly unless improved technology leads to lower cost systems. The need for supplemental power during periods of warm weather contribute to the high cost of dry cooling and have led to greater emphasis on combined dry and wet cooling. Experimental and demonstration programs are underway at several locations in the U.S. to develop new systems which will hopefully reduce the cost of dry and wet/dry systems and/or the need for supplemental power. If any of the projected improvements of these advanced systems can be developed to the point of commercial availability, the use of dry cooling would be greatly increased and many of the secondary benefits will be realized. These include greater freedom to take advantage of existing transmission corridors, multiple plants on presently water-limited sites and mine mount sites in water-limited regions. The more promising advanced concepts under study are reviewed and appraised as to their likelihood of having a significant impact on the future use of dry (including dry/wet) cooling.

  13. 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

  14. 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

  15. Numerical modelling of cooling tower plumes: comparison with experimental data

    To validate the numerical models of cooling tower plumes used in impact studies, EDF has effected a major testing program in the vicinity of the BUGEY nuclear power station, including sets of fine measurements taken from aircraft, teledetection readings and routine measurements effected over a very period (photographs of plumes, micro-meteorological network). The data recorded have allowed two types of models to be validaded: 1) The aim of the first type is to establish statistics of the morphological characteristics of plumes (length, height, etc.) and the resulting micro-climatic changes (i.e. reduction of the duration of sunshine and attenuation of the intensity of overall radiation. This type of model was validated on the basis of the routine measurements carried out over a long period. 2) The second type (a three - dimensional model and a microphysical model of the spectrum), mainly designed for the study of the dynamic and thermodynamic structure of plumes, has been validated on the basis of measurements made during intensive measurements campaigns (formation of artificial cumulus, interaction of the plume with a cloud formation)

  16. 我国冷却塔应用现状及面临的挑战%Applications and Challenges of Cooling Tower in Chin

    费全昌

    2014-01-01

    Cooling tower has been widely used in China. Cooling tower technology started late in China, but experienced rapid development. Several large-scale cooling towers, including natural draft counter-flow cooling tower, seawater cooling tower, tower with flue gas dispersion and indirect dry cooling tower, with nominated water spraying area up to 10,000m2 have been built around China. The large-scale natural draft counter-flow cooling tower for inland nuclear power has also been designing in China. In addition, natural cooling tower with water collecting system and cross flow cooling tower have also been used in small scale and scope. With the dramatic increasing of diameter and height of the cooling tower, how to design large-scale cooling towers with structural safety and high efficiency is the great technical challenge faced by domestic engineers, also creates opportunities for broad international cooperation.%冷却塔在我国火电厂的应用广泛。冷却塔技术在我国的应用起步较晚,但发展极为迅速,尤其是在逆流式通风冷却塔方面,先后建成投产的多座淋水面积超10000m2的超大型自然通风逆流塔(包括海水冷却塔、排烟冷却塔)和超大型间接空冷塔;在内陆核电站冷却塔应用方面,也开展了一系列研究和方案设计;此外,高位收水塔和横流塔方面也有小规模小范围的应用案例。随着冷却塔直径、高度的不断增加,冷却塔已变成火力发电厂内单体体量最大的构筑物,如何设计结构安全、运行安全、冷却效率高的大型冷却塔是我国工程师面临的技术挑战,也给广泛的国际合作创造了条件。

  17. 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

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

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

  19. Replacement of the cooling tower packing at the Goesgen-Daeniken AG nuclear power plant

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

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

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

  2. 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

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

    NONE

    1998-09-01

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

  4. Replacement of asbestos cement fills in natural draft cooling towers

    Gay, G.A.; Stackhouse, D.W.

    1986-01-01

    This paper describes some of the deterioration problems which have been encountered with asbestos cement materials, the environmental and regulatory problems associated with asbestos, and some of the concerns to be addressed replacing fill material in a natural draft tower.

  5. A cooling water system copper corrosion study

    Pulkrabek, J.W.

    1998-07-01

    The plant has four units that have been operating normally for 12--33 years. Two of the units are 70 MW sister units that have copper alloy once-through condensers. The other two units are 350 MW and 500 MW units with copper alloy condensers and cooling towers. No cooling water related tube leaks had been experienced. Until 1993, the only chemicals used were sulfuric acid for pH control of the cooling tower systems and chlorine for biological control. The units were chlorinated for one hour per day per condenser. In early July 1992, their copper grab sample at the plant discharge to the river exceeded the weekly environmental limit. In fact, it was so high that there was a slim chance of coming in under their monthly average copper limit unless something was done quickly. The result of this incident was an extensive study of their plant wastewater and cooling systems. The study revealed that the elevated copper problem had existed sporadically for several years. Initially, copper control was achieved by altering the wastewater treatment processes and cooling tower blowdown flow path. Two extended trials, one with tolyltriazole (TTA) and one with a chemically modified benzotriazole (BZT) were performed. Optimal control of copper corrosion was eventually achieved by the application of a TTA treatment program in which the feed rates are adjusted based on on-line corrosion monitoring measurements. This report documents experiences and results over the past six years.

  6. 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)

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

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

  8. 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

  9. 公共场所大型中央空调冷却塔水、冷凝水中军团菌污染的调查研究%Investigation on Legionella Contamination in Cooling Tower Water and Condensation Water in the Large Central Air Conditioning in Public Places

    季顺锋

    2015-01-01

    Objective Investigation and study of suzhou city in public places large central air conditioning legionella in cooling tower water of condensed water polution.Methods From Augustto September 2015, acquisition of suzhou city 22 hotel,five medical institutions and seven mals. Central air conditioning cooling water use GVPC and BCYE medium, imposed heavy lung cultivation legionela in operation,and adopt serotyping and corresponding verification.Results Through the analysis of the cooling tower water,its eosinophilic lung legionela polution rate was 26.47%(9/34), legionela was isolated public 11 strains. In serotyping,its was mainly LPI,the percentage was 37.5%(6/16).Conclusion Public places of large central air-conditioning cooling tower water in Suzhou city has high rate of legionela bacteria. It is a serious threat to people's health,especialy related to medical institutions,the polution of legionela polution rate proportion is higher than other, need strict control.%目的:调查研究苏州相城区公共场所大型中央空调冷却塔水、冷凝水中军团菌污染情况。方法于2015年8~9月,采集苏州相城区22家宾馆、5家医疗机构及7家大型商场中央空调冷却水,采用GVPC及BCYE培养基,对其实施嗜肺军团菌分离培养操作,并采取血清分型及相应检定。结果经分析,在冷却塔冷却水当中,其嗜肺军团菌的污染率为26.47%(9/34),分离出军团菌公有11株。在血清分型中以LPI为主,所占比例为37.5%(6/16)。结论苏州相城区公共场所大型中央空调冷却塔水、冷凝水存在高的的军团菌检出率,严重威胁市民的健康,特别是相关医疗机构,其军团菌污染率所占比重高于其他,需要对其实施严格控制。

  10. Investigation on Legionella Contamination in Cooling Tower Water and Condensation Water in the Large Central Air Conditioning in Public Places%公共场所大型中央空调冷却塔水、冷凝水中军团菌污染的调查研究

    季顺锋

    2015-01-01

    目的:调查研究苏州相城区公共场所大型中央空调冷却塔水、冷凝水中军团菌污染情况。方法于2015年8~9月,采集苏州相城区22家宾馆、5家医疗机构及7家大型商场中央空调冷却水,采用GVPC及BCYE培养基,对其实施嗜肺军团菌分离培养操作,并采取血清分型及相应检定。结果经分析,在冷却塔冷却水当中,其嗜肺军团菌的污染率为26.47%(9/34),分离出军团菌公有11株。在血清分型中以LPI为主,所占比例为37.5%(6/16)。结论苏州相城区公共场所大型中央空调冷却塔水、冷凝水存在高的的军团菌检出率,严重威胁市民的健康,特别是相关医疗机构,其军团菌污染率所占比重高于其他,需要对其实施严格控制。%Objective Investigation and study of suzhou city in public places large central air conditioning legionella in cooling tower water of condensed water polution.Methods From Augustto September 2015, acquisition of suzhou city 22 hotel,five medical institutions and seven mals. Central air conditioning cooling water use GVPC and BCYE medium, imposed heavy lung cultivation legionela in operation,and adopt serotyping and corresponding verification.Results Through the analysis of the cooling tower water,its eosinophilic lung legionela polution rate was 26.47%(9/34), legionela was isolated public 11 strains. In serotyping,its was mainly LPI,the percentage was 37.5%(6/16).Conclusion Public places of large central air-conditioning cooling tower water in Suzhou city has high rate of legionela bacteria. It is a serious threat to people's health,especialy related to medical institutions,the polution of legionela polution rate proportion is higher than other, need strict control.

  11. 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...

  12. 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.

  13. 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

  14. 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)

  15. Water Towers, Water Towers, Published in Not Provided, 1:1200 (1in=100ft) scale, city of Kingsland.

    NSGIC GIS Inventory (aka Ramona) — This Water Towers dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Field Survey/GPS information as of Not Provided. It is described...

  16. 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

  17. Experimental measurement of cooling tower emissions using image processing of sensitive papers

    Ruiz, J.; Kaiser, A. S.; Ballesta, M.; Gil, A.; Lucas, M.

    2013-04-01

    Cooling tower emissions are harmful for several reasons such as air polluting, wetting, icing and solid particle deposition, but mainly due to human health hazards (i.e. Legionella). There are several methods for measuring drift drops. This paper is focussed on the sensitive paper technique, which is suitable in low drift scenarios and real conditions. The lack of an automatic classification method motivated the development of a digital image process algorithm for the Sensitive Paper method. This paper presents a detailed description of this method, in which, drop-like elements are identified by means of the Canny edge detector combined with some morphological operations. Afterwards, the application of a J48 decision tree is proposed as one of the most relevant contributions. This classification method allows us to discern between stains whose origin is a drop and stains whose origin is not a drop. The method is applied to a real case and results are presented in terms of drift and PM10 emissions. This involves the calculation of the main features of the droplet distribution at the cooling tower exit surface in terms of drop size distribution data, cumulative mass distribution curve and characteristic drop diameters. The Log-normal and the Rosin-Rammler distribution functions have been fitted to the experimental data collected in the tests and it can been concluded that the first one is the most suitable for experimental data among the functions tested (whereas the second one is less suitable). Realistic PM10 calculations include the measurement of drift emissions and Total Dissolved Solids as well as the size and number of drops. Results are compared to the method proposed by the U.S. Environmental Protection Agency assessing its overestimation. Drift emissions have found to be 0.0517% of the recirculating water, which is over the Spanish standards limit (0.05%).

  18. 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

  19. Startup of air-cooled condensers and dry cooling towers at low temperatures of the cooling air

    Milman, O. O.; Ptakhin, A. V.; Kondratev, A. V.; Shifrin, B. A.; Yankov, G. G.

    2016-05-01

    The problems of startup and performance of air-cooled condensers (ACC) and dry cooling towers (DCT) at low cooling air temperatures are considered. Effects of the startup of the ACC at sub-zero temperatures are described. Different options of the ACC heating up are analyzed, and examples of existing technologies are presented (electric heating, heating up with hot air or steam, and internal and external heating). The use of additional heat exchanging sections, steam tracers, in the DCT design is described. The need for high power in cases of electric heating and heating up with hot air is noted. An experimental stand for research and testing of the ACC startup at low temperatures is described. The design of the three-pass ACC unit is given, and its advantages over classical single-pass design at low temperatures are listed. The formation of ice plugs inside the heat exchanging tubes during the start-up of ACC and DCT at low cooling air temperatures is analyzed. Experimental data on the effect of the steam flow rate, steam nozzle distance from the heat-exchange surface, and their orientation in space on the metal temperature were collected, and test results are analyzed. It is noted that the surface temperature at the end of the heat up is almost independent from its initial temperature. Recommendations for the safe start-up of ACCs and DCTs are given. The heating flow necessary to sufficiently heat up heat-exchange surfaces of ACCs and DCTs for the safe startup is estimated. The technology and the process of the heat up of the ACC with the heating steam external supply are described by the example of the startup of the full-scale section of the ACC at sub-zero temperatures of the cooling air, and the advantages of the proposed start-up technology are confirmed.

  20. Transition to a new generation of large natural-draught cooling towers

    A concept of a new generation of natural-draught cooling towers for large nuclear power plant units is presented considering optimization and calculation methods, safety philosophy, dimension criteria, constructional measures, building materials, construction surveying, climbing formwork, and climbing cranes. The first installation will be available by 1990, with a unit 250 m in diameter by 150 m high

  1. 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

  2. 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.

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

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

    1977-06-01

    A previous study undertaken to ascertain the economic incentives for further development of advanced dry/wet cooling towers showed that an advanced dry cooling concept using ammonia as an intermediate cooling fluid reduced the incremental cost of dry cooling by approximately 25 to 30%. This paper presents the projected costs of five alternative dry/wet concepts, one of which involves a similar use of ammonia. This study concludes that although absolute quantitative cost estimates for these cooling systems are uncertain, the relative cost studies indicate that wet/dry cooling systems using ammonia may be competitive with commercially available systems and that the deluge system which links dry and evaporative cooling in an ammonia system should be developed in order to provide a more accurate assessment of the system cost and reliability. (LCL)

  4. 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 μm) 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 μm radius) at 11 tower diameters

  5. Field trial of biocides for control of Legionella in cooling towers.

    Bentham, R H; Broadbent, C R

    1995-03-01

    Legionella and amebae populations in 16 cooling towers were challenged with three commercially available biocide formulations. The active agents were: a chlorinated phenolic thioether (CPTE), bromo-nitro-propane-diol (BNPD), and bromo-chloro-dimethylhydantoin (BCD, in briquette form). The towers were dosed with these biocides for approximately 4 weeks. BCD was effective against Legionella in each of nine challenge experiments, and CPTE in eight of nine challenges. BNPD was effective in only five of 11 challenges. None of the biocides had any significant effect in reducing planktonic amebae concentrations during the challenges. PMID:7765850

  6. Water cooled nuclear reactor

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

  7. The Water Quality Control of the Secondary Cooling Water under a Normal Operation of 30 MWth in HANARO

    HANARO, a multi-purpose research reactor, a 30 MWth open-tank-in-pool type, has been under a full power operation since 2005. The heat generated by the core of HANARO is transferred to the primary cooling water. And the cooling water transfers the heat to the secondary cooling water through the primary cooling heat exchanger. The heat absorbed by the secondary cooling water is removed through a cooling tower. The quality of the secondary cooling water is deteriorated by a temperature variation of the cooling water and a foreign material flowing over the cooling water through the cooling tower fan for a cooling. From these, a corrosion reduces the life time of a system, a scale degrades the heat transfer effect and a sludge and slime induces a local corrosion. For reducing these impacts, the quality of the secondary cooling water is treated by a high ca-hardness water quality program by maintaining a super saturated condition of ions, 12 of a ca-hardness concentration. After an overhaul maintenance of a secondary cooling tower composed of a secondary cooling system in 2007, a secondary cooling water stored in the cooling tower basin was replaced with a fresh city water. In this year, a water quality deterioration test has been performed under a full power operation and a mode of a twenty three day operation and twelve day maintenance for setting a beginning control limit of the secondary cooling water. This paper describes the water quality deterioration test for the secondary cooling system under a full power operation of 30 MWth including a test method, a test requirement and a test result

  8. Cooling water requirements and nuclear power plants

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

  9. 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

  10. 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

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

    Ken Mortensen

    2009-06-30

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

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

    Krishna S. Vishwakarma; Arpit S. Bhoyar

    2015-01-01

    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 t...

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

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

  14. 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.)

  15. 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.)

  16. 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

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

    Lin, Feng; Li, Yi [Department of Building Engineering, Tongji University, No. 1239 Siping Road, Shanghai 200092 (China); Gu, Xianglin, E-mail: gxl@tongji.edu.cn [Department of Building Engineering, Tongji University, No. 1239 Siping Road, Shanghai 200092 (China); Zhao, Xinyuan [Department of Building Engineering, Tongji University, No. 1239 Siping Road, Shanghai 200092 (China); Tang, Dongsheng [Guangdong Electric Power Design Institute, No. 1 Tianfeng Road, Guangzhou, Guangdong 510663 (China)

    2013-05-15

    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

  18. Optimal Environmental Performance of Water-cooled Chiller System with All Variable Speed Configurations

    Yu, Fu Wing; Chan, Kwok Tai

    This study investigates how the environmental performance of water-cooled chiller systems can be optimized by applying load-based speed control to all the system components. New chiller and cooling tower models were developed using a transient systems simulation program called TRNSYS 15 in order to assess the electricity and water consumption of a chiller plant operating for a building cooling load profile. The chiller model was calibrated using manufacturer's performance data and used to analyze the coefficient of performance when the design and control of chiller components are changed. The NTU-effectiveness approach was used for the cooling tower model to consider the heat transfer effectiveness at various air-to-water flow ratios and to identify the makeup water rate. Applying load-based speed control to the cooling tower fans and pumps could save an annual plant operating cost by around 15% relative to an equivalent system with constant speed configurations.

  19. 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

  20. 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 (710 m from the stack and 315 m 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 12 months 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

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

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

    1998-09-01

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

  2. Cooled water rod (loca conditions)

    A process is described for providing a radiation heat sink for fuel bundles having a large water moderator tube in the event of a loss of coolant accident the fuel bundles having an upper tie plate, a lower tie plate, a channel surrounding and connecting the tie plate, a plurality of fuel rods supported between the tie plates and within the channels in side by side upstanding relation; a large water moderator tube having at least twice the diameter of the fuel rods. The process consists of: spraying core cooling spray in an evenly divided flow over the upper tie plate; collecting core cooling spray at an uper end of the large water moderator tube; and distributing the core cooling spray circumferentially along the inner surfaces of the large water moderator tube in a downward flow separating the flow of the core cooling spray from the flow of steam resulting from the flashing of water to steam within the moderator tube

  3. 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.

  4. 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

  5. 冷却塔防冻设计%Frost prevention design for cooling tower

    杨文涛; 易钏

    2014-01-01

    针对冬季北方寒冷地区的冷却塔运行情况,对其产生冰冻的现象和原因进行了分析。从冷却塔产生冰冻现象的各个环节入手,逐一提出了行之有效的解决措施。同时介绍了大型钢混结构机力通风逆流式冷却塔的防冻技术和冬季运行技巧。%In this paper the frost phenomena and resean of the cooling tower are analyzed according to its winter operation in the northern cold region. The effective technique is proposed one by one on basis of the ev-ery segment of its frost penomena. At the same time the anti-freezing technology and the winter operation tech-nique for the large reinforced concrete structure power ventilation counter-flow cooling tower is introduced.

  6. Emission of asbestos fibres from natural-draught cooling towers. Pt. 1 and 2. Part 1: Asbestos determined in plume samples from two natural-draught, wet cooling towers. Pt. 2: Behaviour of wet cooling tower internal structures made of asbestos cement. Emission von Asbestfasern aus Naturzugnasskuehltuermen. T. 1 und 2. Teil 1: Asbestgehalt in Schwadenproben aus zwei Naturzug-Nasskuehltuermen. Teil 2: Verhalten von Asbestzementeinbauten in Nasskuehltuermen

    Ernst, G.; Althaus, E.; Karotke, E.; Grimm, K.; Heumann, H.G.; Rueckert, G.

    1985-01-01

    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 m/sup 3/, 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 10/sup 6/ fibres per m/sup 3/, or 100 ng/m/sup 3/ 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 m/sup 3/ of air; including the extreme data of the single sample mentioned above, the result is some thousand fibres per m/sup 3/. The data are far below the TRK data (Technical guiding data for maximum concentration at the place of work), which state a maximum of 10/sup 6/ fibres per m/sup 3/.

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

    Ken Mortensen

    2011-12-31

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

  8. 浅析降低制盐冷却塔循环水氯根的有效方法与措施%Brief Analysis on Effective Methods and Measures of Reducing the Chlorine in Salt Making Cooling Tower Circulating-Water

    许从胜

    2016-01-01

    It is an inevitable result, which the chlorine is contained in salt making cooling tower circulating-water, of the end of secondary steam entrainment. However, the high chlorine in circulating-water will have corrosion on the equipment so that it will cause vacuum leakage to affect manufacture. In the traditional devices of salt making, when there are no demister and purified water replacement, how to reduce the content of chlorine in circulating-water, and reduce the effect of corrosion on the equipment, this paper according to nearly two years practical quantitative analysis adopts a series of measures and finally achieves twice the result with half the effort.%制盐冷凝塔循环水含有氯根是末效二次蒸汽雾沫夹带必然结果,但循环水高氯根对设备的腐蚀易造成真空泄漏影响生产。在传统的制盐装置中,在没有除沫器和净化水置换情况下,如何降低循环水氯根含量,减少设备腐蚀影响,本文通过定量分析采取一系列措施,经过近两年实践证明,达到事半功倍的效果。

  9. 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

  10. 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

  11. 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)

  12. Application of Energy-saving Technology of No Filler Spray Cooling Tower with Free Electricity%无填料免电喷雾冷却塔节能技术的应用

    盖素霞; 刘立友; 王歌飞

    2013-01-01

      无填料免电喷雾冷却塔是一种新型的工业循环水降温设备,它比普通的填料冷却塔降温效果理想,冷量比普通机械通风填料降温塔提高8-10%,免电喷雾冷却塔对系统的富裕扬程要求偏低,节省95%以上的填料,降低了设备的维修费用。比普通无填料喷雾冷却塔更节能,单塔节约70KW以上,节电效果明显。%No filler spray cooling tower with free electricity is a new kind of industrial circulating water cooling equipment, and its cooling effect is more ideal than ordinary packing cooling tower. Its cooling capacity increases 8-10% than the conventional mechanical ventilation filler cooling tower, and it has lower requirements for the over affluent injecting distance of system, and saves more than 95%of the filler, and reduces the maintenance costs of the equipment. So it saves more energy tan the ordinary no filler spray cooling tower, saving above 70KW, so its energy-saving effect is obvious.

  13. Successful implementation of ageing management exemplified at the cooling tower of Emsland nuclear power plant; Erfolgreiche Umsetzung von Alterungsmanagement am Beispiel Kuehlturm des Kernkraftwerkes Emsland

    Fischer, Alexander [Hochtief Solutions AG, Consult IKS Energy, Frankfurt am Main (Germany). Design Kraftwerke; Dueweling, Carsten [Kernkraftwerke Lippe-Ems GmbH, Lingen (Germany). Abschnitt Bautechnik

    2013-07-15

    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.)

  14. Cooling clothing utilizing water evaporation

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

    2014-01-01

    . To prevent wet discomfort, the T-shirt was made of a polyester material having a water-repellent silicon coating on the inner surface. The chest, front upper arms, and nape of the neck were adopted as the cooling areas of the human body. We conducted human subject experiments in an office with air...

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

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

    1998-09-01

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

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

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

    2012-11-01

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

  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. Study of miniaxial flow turbine in energy-saving cooling towers%轴流式微型水轮机在节能型冷却塔中的应用

    郭润睿; 张国强; 史金华; 费笑勇

    2012-01-01

    在节能型冷却塔中,用微型水轮机替代电动机驱动风扇叶片旋转可以利用循环冷却水的富余能量,节约风扇电机的能耗.然而目前国内对微型水轮机在冷却塔中驱动风机的工作机理研究不足,导致有些工程案例的应用效果不理想.通过分析各型水轮机的结构和性能特点及冷却塔工作的实际条件,制订了微型水轮机结构型式选择的技术规范,在此基础上进行了轴流式水轮机的应用研究,实验结果证明所研制的轴流式水轮机具有优异的性能,相关的研究成果已在若干个工程项目中得到了实际应用且节能效果明显.%In cnergy-saving cooling towers, the miniaxial flow turbine are applied to drive cooling tower fans to replace motors in the conventional cooling towers. With the applied technology, the cooling towers can make full use of the surplus energy of circulating cooling water, while saving the energy consumption of fan motors of cooling towers. However, at present,the working mechanism of mini-hydraulic turbines driving cooling tower fans has not been adequately studied in our country, leading to many non-ideal engineering cases. Based on analyzing the condition of the cooling tower and the structure and performance characteristics of all types of hydroturbine, application criteri-ons and technical specifications of selecting structure type of micro-turbine have been worked out, and then, some application research of axial flow turbine has been done. Experimental results demonstrate that the miniaxial flow turbine applied to drive cooling tower fans has good performance, and relevant research results have been applied in many projects and have get significant energy-saving effect.

  19. 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

  20. Technical heat and flow investigations into heat exchangers made out of synthetic materials, for use in dry cooling towers

    Pollack, H.

    1981-01-01

    Bare tube and flat heat exchangers (HE) made out of synthetic materials were investigated for use in dry cooling towers with natural draft. The advantages of synthetic maternals are higher corrosion resistance, easier workability and lower cost. Suitability tests were performed designing the total system based on HE and tower construction. It is shown that bare tube bundles composed of tube walls or hollow plates separated by plastic strips with wall thicknesses less than 0.6 mm are an alternative to finned tube HE's of metal. Assuming specific building costs of 330 DM/sqm for the tower shell and HE manufacturing costs of 20 DM/kg, several solutions can be found with slight differences in heat transfer conditions and total costs between 22 and 25.10E6 DM.

  1. 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.)

  2. 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)

  3. 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...

  4. 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)

  5. 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

  6. 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.

  7. 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

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

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

    2012-07-01

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

  9. 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

  10. The cooling water from Ringhals

    The Ringhals Nuclear Power Plant is situated on the Swedish west coast about 70 km south of Gothenburg. At present two units operate at a total maximum power level of 1580 MWE and their once-through cooling system requires 80 m3/sec sea water. The temperature of the cooling water increases approximately 10 deg C. This study assesses the spreading of the discharged cooling water in the ambient sea and is based on field data sampled since the end of 1974. About 50 thermal mappings were made in the area by boat or in some cases by aeroplane. Several continously recording current and temperature instruments were used. Water samples analysed for salinity, oxygen and turbidity were collected most of the time. Through the thermal mappings four main directions of the thermal plume were distinguished: northward along the coast (class 1A), northward further out (class 1B), westward and reversing plumes (class 2) and southward (class 3). The changing of the plume hour by hour between these main directions was measured by the recording temperature instruments. Data from almost one year gave the following statistics: 40 percent class 1A + 1B, 15 percent class 2, 25 percent class 3 and 20 percent undefined directions. Furthermore, available data showed that the direction of the ambient current mostly gave the plume direction. The wind, on the other hand, was more uncertain as an indicator of the plume direction. Owing to the varying ambient currents the plume changed its direction more than once a day. Measurable excess temperatures were found within a few kilometers wide zone from Stavder in the north to Norra Horta in the south. The largest measured area with excess temperatures of more than 1 deg C was 6 km2. Usually, however, the plume covered about 2.5 km2 at full production at the power plant. As for the downward spreading, the bottom of the plume normally registrated down to 3-7 m, but occasionally it reached the 10 - 12 m level. The tendency of deep penetration increased

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

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

    2011-07-01

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

  12. 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)

  13. 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

  14. Noise control of counterflow cooling towers%逆流式冷却塔的噪声治理

    费朝阳; 陈长征; 周勃

    2011-01-01

    根据逆流式冷却塔辐射噪声的实测频谱图,分析了冷却塔的主要噪声来源和频谱特征.分别从吸声、消声和隔声等方面制定了降噪方案,取得了良好的降噪效果.%Based on the measured radiation noise frequency spectrogram, analyses the main noise source and noise spectrum characteristics of cooling tower.Makes a noise control scheme from the aspects of sound absorption, attenuation and insulation.The effect of the noise control is satisfactory.

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

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

  16. 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

  17. 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

  18. 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.

  19. Efficient Water Management in Water Cooled Reactors

    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

  20. Molecular characterization and corrosion behavior of thermophilic (55 C) SRB Desulfotomaculum kuznetsovii isolated from cooling tower in petroleum refinery

    Anandkumar, B. [Department of Biotechnology, Sourashtra College, Madurai (India); Choi, J.H. [Electrokinetics Division, Korea ElectroTechnology Research Institute, Changwon (Korea); Venkatachari, G.; Maruthamuthu, S. [Corrosion Protection Division, Central Electro Chemical Research Institute (CECRI), Karaikudi (India)

    2009-09-15

    Desulfotomaculum kuznetsovii (D. Kuznetsovii), a thermophilic sulfate-reducing bacterium (SRB), was identified in a cooling tower of a petroleum refinery by 16S rRNA gene sequencing and its functional gene encoding dissimilatory sulfite reductase (dsrAB). The thermophilic sulfate-reducing bacterial species have been reported for the first time in the cooling towers of an Indian petroleum refinery. The protein coded by dsrAB gene was cloned, expressed, and identified using recombinant DNA technology. Weight loss method, electrochemical and surface analysis showed the corrosion behavior of the isolate. In the presence of D. kuznetsovii, the corrosion rate was higher when compared to control at 55 C. It suppresses the anodic reaction and enhances the cathodic reaction by the production of organic complex and iron sulfide, respectively. Numerous pitting were noticed on mild steel which is due to the presence of D. kuznetsovii and its role in the corrosion process has been discussed. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  1. Physico-chemical interactions between radioactive effluents from a nuclear power station stack and plumes from a cooling tower: effects on ground deposition of radioactivity

    A broad outline of numerical modelling of the interaction between radioactive effluents and plumes from cooling towers will be given and some of the more important aspects dealt with in some detail. The discussion will include the influence of wind direction, the heights reached by the cooling tower plumes, their visible lengths, which in turn depend on prevailing atmospheric conditions (humidity and wind speed), and the influence of natural rain and artificial precipitation (due to vapour droplets from the cooling towers) on the rate of radioactive deposition (fallout and washout). The probable effects of this interaction on the annual radioactive deposition factors will be brought out with the help of results obtained by numerical modelling (the KUMULUS model) for certain atmospheric conditions. The results obtained will be compared with those presented by other authors

  2. 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

  3. Water cooled FBNR nuclear reactor

    elements from the fuel chamber up into the core. A fixed suspended core is formed in the reactor. In the shut down condition, the suspended core breaks down and the fuel elements leave the core and fall back into the fuel chamber by the force of gravity. The fuel elements are made of UO2 micro spheres embedded in zirconium and cladded by zircaloy. Any signal from any of the detectors, due to any initiating event, will cut-off power to the pump, causing the fuel elements to leave the core and fall back into the fuel chamber, where they remain in a highly subcritical and passively cooled conditions. The fuel chamber is cooled by natural convection transferring heat to the water in the tank housing the fuel chamber. The nest step in the development of FBNR is the construction of its prototype. Efforts are being made to secure participants in such an endeavor. (author)

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

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

    1998-09-01

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

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

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

  6. Safety analysis of the natural draft cooling tower block B at the power station Ibbenbueren; Sicherheitsanalyse des Naturzugkuehlturms KW Ibbenbueren Block B

    Dorge, Axel [RWE Power AG, Werne (Germany). Kraftwerke Region Ost Technische Planung/Bautechnik; Eckstein, Ulrich; Woermann, Ralf [Kraetzig und Partner Ingenieurgesellschaft fuer Bautechnik mbH, Bochum (Germany)

    2010-01-15

    Building structures deteriorate during their lifetimes, e.g. they loose their virgin quality. In addition, they grow virtually in age because of permanent modernisation of technical standards. This holds especially for natural draft cooling towers, those power station components of strong importance for economic energy conversion which are highly exposed to atmospheric corrosion. The present manuscript sketches the safety checks of a 25 years old cooling tower, which shall be free of safety deficits for the planned residual service duration of approximately 20 years, although corresponding standards, gained knowledge on response behaviour, and underground coal mining concepts have been improved considerably. (orig.)

  7. Cooling water treatment with ozone. [WEST GERMANY

    Wellauer, R.; Oldani, M. (Asea Brown Boveri, Baden (Switzerland))

    Small scale tests on an open recirculating cooling system with a cooling water flow of 10 m{sup 3}/h conducted for a period of two years have shown that ozone could be a viable alternative to chlorine and other commonly used biocides. An average ozone dosage of 0.05 mg/L was applied continuously to the cooling water. Corrosion rates of copper alloy samples immersed in ozonized water were lower than the rates of samples in nonozonized water. No corrosion was detected for the Cr-Ni steel alloys DIN 1.4306 and DIN 1.4404 as well as for titanium either in the presence or absence of ozone in water. This is ascribed to the formation of a thin protective layer in both cases. A pilot plant has been set up at the EVS Heilbronn coal-fired power station in West Germany in order to confirm the results obtained on small scale. The open recirculating cooling system has a cooling water flow of 1,000 m{sup 3}/h and is fed by conditional Neckar river water. An air-fed ozone generator is used to ozonize a 10% side stream of the cooling water. A bubble diffuser contactor is used to introduce ozone into the water and an air heater is operated to decompose excess ozone leaving the contactor. The plant can be run to yield either a constant ozone residual concentration in the water or a constant ozone dosage to the water leaving the contactor. All relevant data are registered continuously and the plant presently is operated automatically with a constant ozone dosage in the side stream. Corrosion experiments are performed using laboratory heat exchangers, and all physical, chemical, and microbiological data of the cooling water are acquired.

  8. 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

  9. 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.

  10. 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)

  11. 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

  12. 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.

  13. 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

  14. 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.

  15. 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.

  16. 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.

  17. 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

  18. 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.

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

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

  20. 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

  1. 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

  2. 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)

  3. 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

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

    Bean, R.M.

    1983-10-01

    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 ..mu..g/L (parts-per-billion). Evidence was obtained that power plants with cooling towers discharge a significant portion of the haloforms formed during chlorination to the atmosphere. A complex mixture of halogenated phenols was found in the cooling water discharges of the power units. Cooling towers can act to concentrate halogenated phenols to levels approaching those of the haloforms. Examination of samples by capillary gas chromatography/mass spectrometry did not result in identification of any significant concentrations of lipophilic base-neutral compounds that could be shown to be formed by the chlorination process. Total concentrations of lipophilic (Bioabsorbable) and volatile organohalogen material discharged ranged from about 2 to 4 ..mu..g/L. Analysis of sediment samples for organohalogen material suggests that certain chlorination products may accumulate in sediments, although no tissue bioaccumulation could be demonstrated from analysis of a limited number of samples. 58 references, 25 figures, 31 tables.

  5. 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

  6. 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

  7. 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

  8. 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...

  9. Instability of water cooled from above

    The temperature field and convection currents induced in water by convection, evaporation and radiation cooling of its surface were studied. These phenomena occur naturally and continuously in any lake, pond, reservoir or a river but they remain usually unobserved. Mach--Zehnder interferograms taken from the side of a tank of water are here used to measure the temperature distribution and to study the convective currents induced by cooling from the surface. Experiments were performed with initially uniform and thermally-stratified layers of water. Both qualitative and quantitative results of preliminary nature for temperature distribution are presented. Interferograms vividly reveal mixing motions induced by instabilities arising in the surface layer. The onset of manifest convective behavior was determined by visual observations of interferograms

  10. 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

  11. 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

  12. 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

  13. The Unusual Water Cooling Applied on Small Asynchronous Motor

    Sikora, Michal; Vlach, Radek; Navrátil, Petr

    2011-01-01

    This paper is concerned with unconventional water cooling that is primarily intended for medium-power synchronous generators. A configuration of the proposed cooling was briefly described here. A way how to estimate the main thermal resistance related to the new water cooling system was presented here. A small induction motor was selected for practical verification of the proposed cooling concept. Measurements executed on this motor showed correctness of water cooling parameters design and su...

  14. Evaluation of the suitabil[i]ty of Fischer-Tropsch gas-to-liquid (GTL) Primary Column Bottoms as process cooling water : analysis of microbial community dynamics, fouling, scaling and corrosion / Savia Susanna Slabbert

    Slabbert, Savia Susanna

    2007-01-01

    Water in South Africa is becoming limiting due to economic growth, social development and the country's water demand that exceed its water availability. Water conservation in the industry can be accomplished by the reuse of process water instead of direct treatment and discharge. By reusing a process effluent as cooling water in cooling towers, the water requirements of an industry, such as Sasol, will be lower and a zero effluent discharge scenario could be achieved. At Sas...

  15. A supervisory control strategy for building cooling water systems for practical and real time applications

    This paper presents a model based supervisory control strategy for online control of building central cooling water systems to enhance their energy efficiency. The supervisory control strategy seeks the minimum energy input to provide adequate cooling energy for buildings, taking into account the characteristics and interactions of central cooling water systems as well as the requirements and constraints of practical application. Simplified semi-physical chiller and cooling tower models are used to predict the system energy performance and environment quality as well as the system response to changes of control settings. A hybrid optimization technique, namely the PMES (performance map and exhaustive search) based method, is developed and utilized to seek optimal solutions to the optimization problem. The control performance and energy performance of this model based supervisory control strategy are evaluated on the central cooling water system of a high rise commercial office building by comparing with that of the model based supervisory control strategy using a genetic algorithm (GA) as the optimization tool, and the performance map based near optimal control strategy as well as other conventional control strategies for cooling water systems in terms of energy efficiency, control accuracy, computational cost etc. The results showed that this strategy is more energy efficient and computational cost effective than other methods for online practical application

  16. Water-cooled lithium-lead blanket

    The paper is an appendix to a study of the reactor relevance of the NET design concept. The present study examines whether the water-cooled lithium-lead blanket designed for NET can be directly extrapolated to a demonstration (DEMO) reactor. A fundamental requirement of the exercise is that the DEMO design should have a tritium breeding ratio which is higher than that in NET. The water-cooled lithium-lead blanket is discussed with respect to: neutronics design, design parameter survey and thermohydraulics, and engineering design. Results are reported of three-dimensional calculations using the Monte Carlo code MORSE-H to investigate possible neutron leakage between the poloidally disposed breeder tubes, and to determine the global tritium breeding ratio for the final double null machine design. (U.K.)

  17. 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.

  18. 40 CFR 401.14 - Cooling water intake structures.

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Cooling water intake structures. 401.14... 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...

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

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

  20. 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

  1. 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.

  2. Pyrographite water-cooled target analysis

    This report presents a study of two pyrographic water-cooled targets planned for use in the Clinton P. Anderson Meson Physics Facility. A steady-state thermal stress analysis was done that included a parameter study on the physical and numerical variables that affect the problem. The maximum target temperatures and stresses were calculated and compared for a variety of conditions. The comparisons show that the 0.6-cm half-width fin target proposed for the A-2 line is the most vulnerable of the targets analyzed

  3. 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

  4. Application of Cooling Water in Controlled Runout Table Cooling on Hot Strip Mill

    LIU Zheng-dong; I V Samarasekera

    2004-01-01

    The controlled runout table cooling is essential in determining the final mechanical properties and flatness of steel strip. The heat of a hot steel strip is mainly extracted by cooling water during runout. In order to study the heat transfer by water jet impingement boiling during runout, a pilot facility was constructed at the University of British Columbia. On this pilot facility, the water jet impingement tests were carried out under various cooling conditions to investigate the effect of processing parameters, such as cooling water temperature, water jet impingement velocity, initial strip temperature, water flow rate, water nozzle diameter and array of water nozzles, on the heat transfer of heated strip. The results obtained contribute to the optimization of cooling water during runout.

  5. The insitu lining of cooling water piping

    The internal corrosion of cooling water piping as well as other industrial piping is becoming an increasing problem to system reliability. There are various alternatives being offered as solutions to the problem including water treatment, coatings, and piping replacement. The in-place lining of these pipes is becoming increasingly popular as a cost-effective method to control corrosion. A cured-in-place plastic composite system can be installed with minimal dismantling or excavation. This paper will examine case histories of the installations of this lining system in power plants at three (3) locations in the United States and one in France. It will also summarize testing that has been performed on the lining system and tests that are currently being performed

  6. 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

  7. 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.

  8. Basic regulations and standards for and performance of measurements in wet cooling towers; Norm-Grundlagen und praktische Durchfuehrung von Leistungsmessungen an Nasskuehltuermen

    Tesche, W. [Balcke-Duerr GmbH, Ratingen (Germany). Geschaeftsbereich Nasskuehlung

    1998-09-01

    Performance measurement in wet cooling towers is a process well covered and specified by national standards, which meanwhile have been harmonized. The European standard recently eleaborated by the cooling tower manufacturing firms that are members of the VDMA association reflects the state of the art and presents a regulatory framework for applications that has been well tuned to conditions met in practice. Evaluation of measurements relies on a comparative analysis of measured data with the cooling characteristics supplied by the manufacturer, either in the form of a diagram, a computer program, or as tabulated information. (orig./CB) [Deutsch] Leistungsmessungen am Nasskuehlturm sind in laenderspezifischen Normen genau spezifiziert. Die Normen haben sich mittlerweile angeglichen. Die von dem im VDMA zusammengeschlossenen Kuehlturmfirmen erarbeitete Euronorm zu diesem Thema spiegelt den aktuellen Stand in einer praxisnahen Durchfuehrungsverordnung wieder. Die Bewertung der Messung erfolgt im Vergleich mit der vor Messbeginn bekannten Kuehlcharakteristik, die entweder als Diagramm, Rechenprogramm oder zumindest als Tabelle vom Lieferanten erstellt wurde. (orig./GL)

  9. 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)

  10. 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

  11. 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)

  12. 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)

  13. 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)

  14. Selective brain cooling reduces water turnover in dehydrated sheep.

    W Maartin Strauss

    Full Text Available In artiodactyls, arterial blood destined for the brain can be cooled through counter-current heat exchange within the cavernous sinus via a process called selective brain cooling. We test the hypothesis that selective brain cooling, which results in lowered hypothalamic temperature, contributes to water conservation in sheep. Nine Dorper sheep, instrumented to provide measurements of carotid blood and brain temperature, were dosed with deuterium oxide (D2O, exposed to heat for 8 days (40 ◦C for 6-h per day and deprived of water for the last five days (days 3 to 8. Plasma osmolality increased and the body water fraction decreased over the five days of water deprivation, with the sheep losing 16.7% of their body mass. Following water deprivation, both the mean 24h carotid blood temperature and the mean 24h brain temperature increased, but carotid blood temperature increased more than did brain temperature resulting in increased selective brain cooling. There was considerable inter-individual variation in the degree to which individual sheep used selective brain cooling. In general, sheep spent more time using selective brain cooling, and it was of greater magnitude, when dehydrated compared to when they were euhydrated. We found a significant positive correlation between selective brain cooling magnitude and osmolality (an index of hydration state. Both the magnitude of selective brain cooling and the proportion of time that sheep spent selective brain cooling were negatively correlated with water turnover. Sheep that used selective brain cooling more frequently, and with greater magnitude, lost less water than did conspecifics using selective brain cooling less efficiently. Our results show that a 50 kg sheep can save 2.6L of water per day (~60% of daily water intake when it employs selective brain cooling for 50% of the day during heat exposure. We conclude that selective brain cooling has a water conservation function in artiodactyls.

  15. Epidemiological investigation and case-control study: a Legionnaires' disease outbreak associated with cooling towers in Warstein, Germany, August-September 2013.

    Maisa, Anna; Brockmann, Ansgar; Renken, Frank; Lück, Christian; Pleischl, Stefan; Exner, Martin; Daniels-Haardt, Inka; Jurke, Annette

    2015-01-01

    Between 1 August and 6 September 2013, an outbreak of Legionnaires' disease (LD) with 159 suspected cases occurred in Warstein, North Rhine-Westphalia, Germany. The outbreak consisted of 78 laboratory-confirmed cases of LD, including one fatality, with a case fatality rate of 1%. Legionella pneumophila, serogroup 1, subtype Knoxville, sequence type 345, was identified as the epidemic strain. A case-control study was conducted to identify possible sources of infection. In univariable analysis, cases were almost five times more likely to smoke than controls (odds ratio (OR): 4.81; 95% confidence interval (CI): 2.33-9.93; p outbreak of LD in Germany to date. Due to a series of uncommon events, this outbreak was most likely caused by multiple sources involving industrial cooling towers. Quick epidemiological assessment, source tracing and shutting down of potential sources as well as rapid laboratory testing and early treatment are necessary to reduce morbidity and mortality. Maintenance of cooling towers must be carried out according to specification to prevent similar LD outbreaks in the future. PMID:26607018

  16. A practical application for the chemical treatment of Southern California`s reclaimed, Title 22 water for use as makeup water for recirculating cooling water systems

    Zakrzewski, J. [Calgon Corp., Pittsburgh, PA (United States); Cosulich, J.; Bartling, E. [County Sanitation Districts of Los Angeles County, Whittier, CA (United States)

    1998-12-31

    Pilot cooling water studies conducted at a Southern California landfill/cogeneration station demonstrated a successful chemical treatment program for recirculating cooling water that used unnitrified, reclaimed, Title 22 water as the primary makeup water source. The constituents in the reclaimed water are supplied by variety of residential and waste water sources resulting in a water quality that may vary to a greater degree than domestic water supplies. This water contains high concentrations of orthophosphate, ammonia, chlorides and suspended solids. The impact of which, under cycled conditions is calcium orthophosphate scaling, high corrosion of yellow metal and mild steel, stress cracking of copper alloys and stainless steel and rapidly growing biological activity. A mobile cooling water testing laboratory with two pilot recirculating water systems modeled the cogeneration station`s cooling tower operating conditions and parameters. The tube and shell, tube side cooling heat exchangers were fitted with 443 admiralty, 90/10 copper nickel, 316 stainless steel and 1202 mild steel heat exchanger tubes. Coupons and Corrater electrodes were also installed. A chemical treatment program consisting of 60/40 AA/AMPS copolymer for scale, deposits and dispersion, sodium tolyltriazole for yellow metal corrosion, and a bromination program to control the biological activity was utilized in the pilot systems. Recirculating water orthophosphate concentrations reached levels of 70 mg/L as PO, and ammonia concentrations reached levels of 35 mg/L, as total NH3. The study successfully demonstrated a chemical treatment program to control scale and deposition, minimize admiralty, 90/10 copper nickel and carbon steel corrosion rates, prevent non-heat transfer yellow metal and stainless steel stress cracking, and control the biological activity in this high nutrient water.

  17. 湿式机械通风逆流冷却塔冷却能力检测%Cooling capacity testing of wet mechanical-draft counter-flow cooling tower

    张春蕾; 丁琦; 魏巍

    2011-01-01

    Based on the design standards and testing regulations for the mechanical draft cooling tower,for the cooling towers with their thermal performance curves not provided by designers, verifies the referred parameter formulas in design standards and testing procedures by practical testing and Excel programming. Especially makes a profound study on the calculation method of the cooling number Ω(a characteristic number) and clarifies some ambiguous terms in the testing regulation.%依据机械通风冷却塔工艺设计规范和冷却塔的测试规程,对设计单位未给出其设计热力性能曲线的冷却塔,通过实际测试与Excel编程对设计规范和测试规程中提到的性能参数计算公式进行了验证,特别是对其冷却数Ω(特征数)的计算方法进行了深入研究,对测试规程中模糊的术语进行了阐述.

  18. 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)

  19. Mountains of the world: vulnerable water towers for the 21st century.

    Messerli, Bruno; Viviroli, Daniel; Weingartner, Rolf

    2004-11-01

    Mountains as "Water Towers" play an important role for the surrounding lowlands. This is particularly true of the world's semiarid and arid zones, where the contributions of mountains to total discharge are 50-90%. Taking into account the increasing water scarcity in these regions, especially for irrigation and food production, then today's state of knowledge in mountain hydrology makes sustainable water management and an assessment of vulnerability quite difficult. Following the IPCC report, the zone of maximum temperature increase in a 2 x CO2 state extends from low elevation in the arctic and sub-arctic to high elevation in the tropics and subtropics. The planned GCOS climate stations do not reach this elevation of high temperature change, although there are many high mountain peaks with the necessary sensitive and vulnerable ecosystems. Worldwide, more than 700 million people live in mountain areas, of these, 625 million are in developing countries. Probably more than half of these 625 million people are vulnerable to food insecurity. Consequences of this insecurity can be emigration or overuse of mountain ecosystems. Overuse of the ecosystems will, ultimately, have negative effects on the environment and especially on water resources. New research initiatives and new high mountain observatories are needed in order to understand the ongoing natural and human processes and their impacts on the adjacent lowlands. PMID:15575180

  20. 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

  1. Water cooled absorption chillers for solar cooling applications

    Biermann, W. J.; Reimann, R. C.

    1982-03-01

    A broad line of absorption chillers designed to operate with hot fluids at as low a temperature as practical while rejecting heat to a stream of water was developed. A packaging concept for solar application in which controls, pumps, valves and other system components could be factor assembled into a unitary solar module was investigated.

  2. 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.

  3. 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

  4. Temporary cooling system for critical loads during Recirculation Cooling Water (RCW) system outage

    As part of the Point Lepreau Refurbishment Project, Recirculation Cooling Water (RCW) system will be shutdown for maintenance activity. During the RCW outage, alternate cooling flow for critical heat loads such as Spent Fuel Bay (SFB), D2O vapour dryers and Instrument Air Compressor Coolers will be provided through a temporary cooling system to remove approximately 3MW of heat. This paper describes a practical strategy to build in the temporary cooling system for this project. Major equipment involved, piping modifications required and system reliability analysis are also addressed. (author)

  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. APPLICATION OF QUALITY FUNCTION DEPLOYMENT METHOD AND FUZZY LOGIC FOR IMPROVING THE DESIGN CHARACTERISTICS IN FRP COOLING TOWER-CASE STUDY

    G.MOHAN KUMAR

    2012-07-01

    Full Text Available Quality Function Deployment is a continuous improvement technique applied in the design of an FRP cooling tower.QFD helps to develop customer oriented, higher quality products. In order to improve the quality characteristics of this product and to satisfy the customers, the technique such as QFD followed by fuzzy logic technique approach is done. Though, the QFD method has some draw backs, it is one of the most important methods to interpret customer needs for specific quality development. To overcome this drawback, fuzzy linguistics approach is proposed in this paper. This paper shows how QFD approach can be combined with fuzzy logic to resolve some of its drawback. Finally, these two approaches have been compared to know whichapplies the best for this case study.

  7. Hydrodynamic analysis and calculation of metal temperature distribution in spiral water wall of ultra supercritical tower boiler

    Shen, Chengwu; Yang, Dong; Yao, Danhua; Zhu, Yufeng; Xu, Xueyuan

    2013-07-01

    In this paper, the spiral water wall system of a 1000MW ultra supercritical tower boiler is simplified as a network system, consisting of circuits, pressure grids and connecting tubes. The establishment of the mathematical model for calculating the mass flux distribution and metal temperature in water wall is based on the mass, momentum and energy conservation equations. The water wall flow distribution and temperature profile of the boiler were computed. The result shows that the differences of outlet temperature and mass flux are small in spiral tube water wall at BMCR, 75%BMCR load and 40%BMCR load. The metal temperatures are all in the allowable ranger.

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

    C. McGowin; M. DiFilippo; L. Weintraub

    2006-06-30

    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.

  9. Control Strategy of Time Interval with Temperature Difference Control for Heat Pump System with Hybrid of Cooling Tower and Ground Source%冷却塔复合地源热泵分时段温差控制策略

    彭金焘; 雷波; 孙亮亮

    2014-01-01

    A new control strategy applied to Heat Pump Air-Conditioning system with hybrid of cooling tower and ground source cooling water system, Time Interval with Temperature Difference Control (TITDC), is proposed in the article. And then a simulation model is developing for a case study building, by using a building energy simulation tool, TRNSYS, to verify the advantages of the new TITDC strategy contrasted to Temperature Difference Control (TDC) stategy on the critical parameters of annual ground heat energy balance, load satisfied percentage for long term and energy consumption.%提出了一种用于冷却塔复合地源热泵空调系统的新型控制策略-分时段温差控制。然后通过对一个具体冷却塔复合地源热泵空调系统的TRNSYS模拟,从土壤的取放热量平衡、系统能否长期满足空调要求和系统的能耗三个方面综合分析了系统的运行控制采用分时段温差控制较采用温差控制的优点。

  10. 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.

  11. Prototype solar heating and cooling systems, including potable hot water

    Bloomquist, D.; Oonk, R. L.

    1977-01-01

    Progress made in the development, delivery, and support of two prototype solar heating and cooling systems including potable hot water is reported. The system consists of the following subsystems: collector, auxiliary heating, potable hot water, storage, control, transport, and government-furnished site data acquisition. A comparison of the proposed Solaron Heat Pump and Solar Desiccant Heating and Cooling Systems, installation drawings, data on the Akron House at Akron, Ohio, and other program activities are included.

  12. 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

  13. 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

  14. 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.)

  15. Cooling of gas turbines IX : cooling effects from use of ceramic coatings on water-cooled turbine blades

    Brown, W Byron; Livingood, John N B

    1948-01-01

    The hottest part of a turbine blade is likely to be the trailing portion. When the blades are cooled and when water is used as the coolant, the cooling passages are placed as close as possible to the trailing edge in order to cool this portion. In some cases, however, the trailing portion of the blade is so narrow, for aerodynamic reasons, that water passages cannot be located very near the trailing edge. Because ceramic coatings offer the possibility of protection for the trailing part of such narrow blades, a theoretical study has been made of the cooling effect of a ceramic coating on: (1) the blade-metal temperature when the gas temperature is unchanged, and (2) the gas temperature when the metal temperature is unchanged. Comparison is also made between the changes in the blade or gas temperatures produced by ceramic coatings and the changes produced by moving the cooling passages nearer the trailing edge. This comparison was made to provide a standard for evaluating the gains obtainable with ceramic coatings as compared to those obtainable by constructing the turbine blade in such a manner that water passages could be located very near the trailing edge.

  16. 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)

  17. 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

  18. 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 the use of the model 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 sensitivity analysis was performed by selecting a nominal condition and determining performance sensitivity for each variable with others held constant. The variables considered in the study 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 indicated in particular 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.

  19. 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

  20. 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

  1. 40 CFR 749.68 - Hexavalent chromium-based water treatment chemicals in cooling systems.

    2010-07-01

    ... Cooling Systems § 749.68 Hexavalent chromium-based water treatment chemicals in cooling systems. (a... distribution in commerce of hexavalent chromium-based water treatment chemicals for use in cooling systems. (d... holds hexavalent chromium-based water treatment chemicals for use in cooling systems. (6) Cooling...

  2. Experiences on condenser cooling water treatment programme at NAPS

    The Narora Atomic Power Station has twin units of 220 MWe pressurized heavy water reactors, situated at the banks of river Ganges in Bulandshahr District of Uttar Pradesh. The plant cooling water takes the make up water supply from river Ganges after pretreatment using polyelectrolyte at two number of clariflocculators. The condenser cooling water system of the station is of open recirculating type and the clarified raw water used as a cooling medium is having a concentration cycle of cooling about 2.0. The calcium concentration in recirculating water is around 160 mg/litre as CaCO3 at full power of the unit. The Langelier Saturation Index of the recirculating water is observed to be in the range + 1.2 to + 1.8, indicating moderately high tendency, towards scale formation on heat transfer surfaces, such as condenser tubes, Turbine lubricating oil coolers and other associated heat exchangers. The condenser cooling water treatment was not envisaged in the original design. Therefore untreated surface water resulting in scale formation (0.3 to 0.5 mm thickness) due to deposition of calcium carbonate was observed in the condenser tubes of NAPS Unit 1 and 2 during initial period of operation (1989 to 1992). It was observed that the scaling on condenser tube surfaces caused increase in terminal temperature difference (TTD) from a design value of 5.5 degC to 13.0 degC. In addition to this a substantial drop in heat transfer coefficient from a value of about 2000 kcal/hr/m2/degC to 1200 kcal/hr/m2/degC occurred. On thorough review actions were initiated at NAPS to restore the heat transfer through condensers. The present paper highlights the experiences on the treatment of cooling water

  3. 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

  4. 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.

  5. Fish culture using cooling water from thermal power plants

    Special problems associated with the use of heated effluents from thermal power plants in aquaculture include fluctuating temperatures, chemicals added to cooling water, gas supersaturation, and inflexibility in the effluent temperature, in many cases obviating a continuous one year culture cycle. In Sweden, salmonids are the preferred cultural species as long as water temperatures do not exceed 20 deg C during the summer. A pilot fish farm is now using cooling water from he Oskarshamn nuclear power plant. An additional concern in this case will be the accumulation of radioisotopes. (E.C.B.)

  6. 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.

  7. 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

  8. 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.

  9. Cooling of concrete structure in advanced heavy water reactor

    Innovative nuclear power plants are being designed by incorporation of passive systems to the extent possible for enhancing the safety by elimination of active components. BARC has designed Advanced Heavy Water Reactor (AHWR) incorporating several passive systems to facilitate the fulfillment of safety functions of the reactor during normal operation, residual heat removal, emergency core cooling, confinement of radioactivity etc. In addition to these passive systems, an innovative passive technology is being developed to protect, the concrete structure in high temperature zone (V1-volume). Passive Concrete Cooling System (PConCS) uses the principle of natural circulation to provide cooling outside the insulation cabinet encompassing high temperature piping. Cooling water is circulated from overhead GDWP in cooling pipes fixed over corrugated plate on outer surface of insulation cabinet and maintains low temperature of concrete structure. Modular construction of insulation cabinet and cooling pipes external to the concrete surface simplifies the design, construction and refurbishment if required. The paper describes the details of passive technology for concrete cooling. (author)

  10. 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

  11. 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

  12. Prevalence of mip virulence gene and PCR-base sequence typing of Legionella pneumophila from cooling water systems of two cities in Iran.

    Ahmadrajabi, Roya; Shakibaie, Mohammad Reza; Iranmanesh, Zahra; Mollaei, Hamid Reza; Sobhanipoor, Mohammad Hossein

    2016-07-01

    Legionella pneumophila is the primary respiratory pathogen and mostly transmitted to human through water cooling systems and cause mild to severe pneumonia with high mortality rate especially in elderly both in hospitals and community. However, current Legionella risk assessments may be compromised by uncertainties in Legionella detection methods. Here, we investigated the presence of L. pneumophila mip gene in water samples collected from different hospitals cooling towers, nursing homes and building/hotels water coolants from two geographical locations of Iran (Kerman and Bam cities) during summer season of 2015 by both nested and real-time PCR methods. Analysis of the 128 water samples for presence of the mip gene by nested-PCR revealed, 18 (23%) positive cases in Kerman and 7(14%) in Bam. However, when samples were tested by real-time PCR, we identified 4 more new cases of L. pneumophila in the hospitals as well as nursing homes water systems that were missed by nested-PCR. The highest rate of contamination was detected in water obtained from hospitals cooling towers in both the cities (p≤0.05). Dendrogram analysis and clonal relationship by PCR-base sequence typing (SBT) of the L. pneumophila genomic DNAs in Kerman water samples showed close clonal similarities among the isolates, in contrast, isolates identified from Bam city demonstrated two fingerprint patterns. The clones from hospital water samples were more related to the L. pneumophila serogroup- 1. PMID:27028760

  13. EXPERIMENTAL RESEARCH OF HEAT- CONDUCTING PLASTIC PIPES APPLIED IN THE CLOSED COOLING TOWER%导热塑料管应用于闭式冷却塔的实验研究

    章立新; 白亮; 范志远; 吴晓芬; 陈岩永; 刘婧楠; 姬翔宇

    2012-01-01

    传统闭式冷却塔采用的金属盘管抗冻和耐腐蚀性差,严重制约了闭式冷却塔的推广使用.导热塑料管具有良好的抗冻性、耐腐蚀性和阻垢性,理论计算在闭式冷却塔中应用具有可行性.本文通过实验研究,得出现有的导热塑料管抗冻性可以满足闭式冷却塔需求,但是导热系数还偏小,大规模推广替代金属管还需要继续提高管材的导热系数.%Metal coils used in the traditional closed cooling tower have bad freezing tolerance and inoxidability, which has seriously impeded the use and promotion of closed towers. The heat - conducting plastic pipe has good freezing tolerance, inoxidability, scale inhibition, according to theoretical calculation, its application in the closed tower is available. This paper has come to the conclusion through experimental research that freezing tolerance of the heat - conducting plastic pipe can meet the needs of closed cooling towers, while the thermal conductivity is relatively small. Therefore, improving the thermal conductivity of the pipe is the way to its large - scale promotion.

  14. 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)

  15. Saved-energy analysis of francis turbine on hydraulic cooling tower%水力冷却塔水轮机的节能分析

    张兰金; 阳莉; 陈德新; 任岩

    2012-01-01

    以水力冷却塔水轮机代替电动机驱动风机,节省了电机所消耗的电能,但是水轮机串联于冷却水循环系统中,增加了水循环系统的水力阻力,须消耗一部分水能克服水力阻力.利用试验和数值分析两种方法,研究了水循环系统中水轮机所引起的水力损失特点,提出水轮机节能的措施.%Francis lurbine replaces the motor to drive the fan on cooling towerf and saves the electric energy of motor. On the other hand, the turhine, which is connected to the cooling water cycle system in series, being series connection of cooling water system, increases the hydraulic head loss of cooling water system, andas well as costs some water energy to overcome itself hydraulic forcemore. This paper studies the hydraulic loss of the turbine by test and CFD. And something areis suggested to decrease the hydraulic loss of turhine.

  16. 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

  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. Electricity prices, river temperatures and cooling water scarcity

    McDermott, Grant; Nilsen, Øivind Anti

    2012-01-01

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

  19. 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 ...

  20. 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)

  1. Data-driven modeling and optimal operation simulation of a cooling tower%数据驱动的冷却水塔建模与节能优化操作

    计青山; 王娟娟; 肖前平; 王建国

    2014-01-01

    针对冷却水塔的节能操作给出了一种数据驱动的建模与优化方法。首先,基于冷却水塔实际运行数据,应用非负绞杀变量选择方法给出一个自适应模型用于描述冷却水塔过程,该模型对于冷却水塔出口水温具有良好的预测精度。根据变量选择结果,分析了外界空气温度与湿度对冷却能力的影响。然后,提出了基于模型的冷却水塔风机的优化操作策略,并进行实验将之应用于冷却水塔的操作。研究结果显示,基于模型的优化操作具有较大的节能空间。%This paper proposed a data-driven modeling and optimalization approach to investigate the operation of a cooling tower for energy conservation. Firstly, based on data from the actual operation of a cooling tower, the cooling tower process was characterized by an adaptive model with nonnegative garrote (NNG) variable selection procedure. On the basis of the statistical results of variable selection, the effects of ambient air temperature and humidity on the cooling capacity of the tower were investigated. Subsequently, the model-based optimal strategy of fan operation was proposed, and its implementation was virtually studied. The research results showed that there was considerable room for energy conservation.

  2. Feasibility and deployment strategy of water cooled thorium breeder reactor

    The author have studied water cooled thorium breeder reactor based on matured pressurized water reactor (PWR) plant technology for several years. Through these studies it is concluded that reduced moderated core by arranging fuel pins in a triangular tight lattice array with heavy water coolant in the primary loop by replacing original light water is appropriate for achieving sufficient breeding performance as sustainable fission system and high enough burn-up as an economical power plant. The heavy water cooled thorium reactor is feasible to be introduced by using Pu recovered from spent fuel of LWR, keeping continuity with current LWR infrastructure. This thorium reactor can be operated as sustainable energy supplier and also MA transmuter to realize future society with less long-lived nuclear waste

  3. Desiccant Dewpoint Cooling System Independent of External Water Sources

    Bellemo, Lorenzo; Elmegaard, Brian; Markussen, Wiebke B.;

    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. This solution is applied to a system with a desiccant wheel dehumidifier and a dew point cooler, termed...... 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...

  4. The insitu lining of cooling water piping

    Insituform is a unique process for reconstructing damaged pipeline systems in municipal and industrial applications, including piping at power plants. A new Cured-in-Place Pipe (CIPP), or Insitupipe, is formed inside of the existing conduit by using fluid pressure, typically water, to install a flexible tube saturated with a liquid thermosetting resin; the water is then heated to harden the resin. This process results in a continuous, tight-fitting, pipe-within-a-pipe. The Insituform process is cost-effective, fast and can be used in a variety of gravity and pressure applications such as sanitary sewers, storm sewers, process piping, water systems, and ventilation systems. This process is versatile enough to be used for stand alone structural reconstruction or it can merely serve as a plastic corrosion barrier to shield existing metal pipe walls from the flow stream which may be contributing to the degradation of wall thickness. For this reason, as well as its attractive life cycle costs, more power plants are turning to this technology for life extension of existing piping

  5. 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

  6. 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

  7. 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

  8. Can rupture detector for water cooled piles

    The object of this study was to develop a simple, easy to-build, apparatus for showing the appearance of a defect on a fuel element can of a swimming pool reactor. The apparatus used consists of a coil of activated carbon around a NaI(Tl) crystal. Through this coil pass the gases obtained by degassing a sample of water from the reactor; the fission gases which appear when a can leaks are trapped in the carbon; the NaI(Tl) crystal is coupled with a photomultiplier followed by a single-channel selector fixed on a photo-electric peak characteristic of the γ spectrum of fission gases. Preliminary experiments were carried out in laboratory; a more complete device was then built and is now working in the reactor Melusine. (author)

  9. 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).

  10. 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)

  11. 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.

  12. Construction technology of inverted awl shell water tower%倒锥壳水塔施工技术

    孙萍

    2011-01-01

    结合具体工程实例,阐述了倒锥壳水塔支筒采用液压滑模施工技术,指出水箱在地面预制后采用倒装液压穿孔千斤顶提升,能够提高施工速度,保障操作人员在高空施工中的安全,值得推广。%Combining with specific engineering example,it describes hydraulic sliding formwork construction technology used in inverted awl shell water tower,points out that water tank applies inverted hydraulic piercing lifting jack lifting after prefabrication on the ground,which can improve construction speed,guarantee operation personnel's safety in the air construction.Thus,it is worth promoting.

  13. Materials challenges for the Supercritical Water-Cooled Reactor (SCWR)

    This paper discusses the materials requirements of the Supercritical Water-cooled Reactor (SCWR) which arise from its severe expected operating conditions: (i) Outlet Temperature (to 650 C); (ii) Pressure of 25 MPa for the coolant containment, (iii) Thermochemical stress in the presence of supercritical water, and (iv) Radiative damage (up to 150 dpa for the fast spectrum variant). These operating conditions are reviewed; the phenomenology of materials in the supercritical water environment that create the materials challenges is discussed; knowledge gaps are identified, and efforts to understand material behaviour under the operating conditions expected in the SCWR are described. (author)

  14. 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

  15. 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 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 6Li(n,α)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

  16. 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

  17. The major species of heavy metal aerosol resulting from water cooling systems and spray dryer systems during incineration processes

    Wey; Yang; Wei

    1998-11-01

    Trace toxic metals in municipal solid waste may escape from the incineration process in flue gas, in dry collected ash, in wet scrubbed ash, or as a suspended aerosol. Therefore, understanding the behavior of heavy metals in the flue gas and the best controls in the air pollution control equipment are important and necessary. The control conditions of water cooling and spray dryer systems during incineration processes significantly influence the formation of heavy metal compounds. The formation of chromium (Cr), lead (Pb), and cadmium (Cd) species under various control conditions (water cooling tower and spray dryer reactor) was investigated in this study. The object of the experiment is to understand the effects of water cooling and spray dryer systems individually on the formation of heavy metal species. The operating parameters that are evaluated include different control systems, control temperatures, and chlorine content. A thermodynamic equilibrium model was also used to evaluate experimental data. In order to match real incineration conditions, a two-stage simulation was performed in this experiment. The results showed that the relationship of speciation between the simulation prediction and X-ray diffraction (XRD) analysis is consistent for Cr compounds; both indicated that Cr2O3 is the major species. The relationship is almost the same for Cd compounds, but not for Pb compounds. PMID:9846130

  18. 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.

  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. 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)

  1. 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

  2. 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.

  3. Water Cooled TJ Dense Array Modules for Parabolic Dishes

    Löckenhoff, Rüdiger; Kubera, Tim; Rasch, Klaus Dieter

    2010-10-01

    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.

  4. 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

  5. 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)

  6. 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

  7. 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

  8. 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.

  9. Characteristic Study on Cool Storage in Transition Period of Cooling Tower-Ground Coupled Heat Pump in Hot-summer and Cold-winter Zone%夏热冬冷地区冷却塔—土壤耦合热泵过渡季蓄冷特性研究

    谢莉; 刘金祥; 刘凯

    2013-01-01

    This paper proposes a soil cool storage model for cooling tower-ground coupled heat pump in transition period based on cooling and heating load characteristics in hot-summer and cold-winter zone,establishes a simulation model for the soil cool storage system of cooling tower-ground coupled heat pump in transition period by means of software TRNSYS,conducts working condition simulation analysis of the two main influencing factors of the model regarding soil cool storage in transition period and proposes a control strategy regarding soil cool storage in transition period for cooling tower-ground coupled heat pump.Besides,this paper also strives to explore an effective method to relieve yearly thermal imbalance of ground-source heat pump in hot-summer and cold-winter zone and improve system operation efficiency based on the researches above.%本文针对夏热冬冷地区冷热负荷特性,提出了冷却塔—土壤耦合热泵过渡季土壤蓄冷模式,采用软件TRNSYS建立了冷却塔—土壤耦合热泵过渡季土壤蓄冷系统仿真模型,并利用该模型针对过渡季土壤蓄冷的两个主要影响因素进行了工况模拟分析,,在此基础上提出了冷却塔—土壤耦合热泵过渡季节土壤蓄冷的控制策略.本文力图通过上述研究探索出缓解夏热冬冷地区土壤源热泵系统全年热失衡问题、提高该系统运行效率的有效途径.

  10. 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.

  11. 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.)

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

    Kent Zammit; Michael N. DiFilippo

    2005-01-01

    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. Produced water is generated nationally as a byproduct of oil and gas production. Seven states generate 90 percent of the produced water in the continental US. About 37 percent of the sources documented in the US Geological Survey's (USGS) Produced Waters Database have a TDS of less than 30,000 mg/l. This is significant because produced water treatment for reuse in power plants was found to be very costly above 30,000 mg/l TDS. For the purposes of this report, produced water treatment was assessed using the technologies evaluated for the San Juan Generating Station (SJGS) in Deliverable 3, Treatment and Disposal Analysis. Also, a methodology was developed to readily estimate capital and operating costs for produced water treatment. Two examples are presented to show how the cost estimating methodology can be used to evaluate the cost of treatment of produced water at power plants close to oil and gas production.

  13. DEVELOPMENT OF SINGLE-PHASED WATER-COOLING RADIATOR FOR COMPUTER CHIP

    ZENG Ping; CHENG Guangming; LIU Jiulong; YANG Zhigang; SUN Xiaofeng; PENG Taijiang

    2007-01-01

    In order to cool computer chip efficiently with the least noise, a single phase water-cooling radiator for computer chip driven by piezoelectric pump with two parallel-connection chambers is developed. The structure and work principle of this radiator is described. Material, processing method and design principles of whole radiator are also explained. Finite element analysis (FEA) software,ANSYS, is used to simulate the heat distribution in the radiator. Testing equipments for water-cooling radiator are also listed. By experimental tests, influences of flowrate inside the cooling system and fan on chip cooling are explicated. This water-cooling radiator is proved more efficient than current air-cooling radiator with comparison experiments. During cooling the heater which simulates the working of computer chip with different power, the water-cooling radiator needs shorter time to reach lower steady temperatures than current air-cooling radiator.

  14. 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

  15. 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)

  16. 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...

  17. 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)....

  18. 土壤源热泵与冷却塔复合运行的优化模式分析*%Optimal Model on the Composite Operation of Earth Source Heat Pump and the Cooling Tower

    黄凯; 许锦峰

    2013-01-01

    以南京典型公共建筑作为研究对象,以土壤源热泵系统与冷却塔复合运行模式优化为目标。针对南京地区公共建筑夏季负荷的特点,通过分析地下土壤温度和空气湿球温度对土壤源热泵系统和冷却塔散热系统性能的影响,得到了土壤源热泵与冷却塔复合运行的优化策略,并给出了优化策略运行模式下暖通空调机组的设计建议和节能潜力分析。%The research object is the typical public building in Nanjing. The objective is optimizing the composite operation model of earth source heat pump and the cooling tower. Based on characteristics of summer load in public buildings in Nanjing, the influence of soil temperature and wet bulb temperature on the properties of earth source heat pump system and the cooling tower heat-removal system was an-alyzed. The optimization strategy of earth source heat pump and the cooling tower composite operation was obtained. Design suggestions and energy-saving potential analysis of HVAC unit in the operation mode of optimization strategy were proposed.

  19. 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)

  20. 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.

  1. 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

  2. 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

  3. 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.

  4. Analysis of Steam Condensation in a Finned Tube of Air-Water Combined Cooling System

    Kwon, Taesoon; Bae, S. W.; Kim, K. H.; Park, Y. S.; Park, H. S. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    A Passive Auxiliary Feedwater System (PAFS) is one of the passive cooling systems of the existing power plant and the operating period is 8 hours because of the limited capacity of the cooling water tank. Therefore, to increase the operating period from 8 to 72 hours for an existing PAFS, the capacity of the cooling water tank should be increased up to 3-4 times. To resolve the excessive increase of the cooling tank volume in water cooling systems, an air-water combined passive cooling system is proposed. In this combined cooling system, the core cooling during the initial stage of an accident having high decay power depends on the water cooling systems such as PAFS. For the later phase of an accident, an air-cooling system is applied to the core cooling. In the operation of the air-cooling system, the steam from the cooling water tank of the PAFS is condensed and recirculated to the cooling water tank by an air-cooling heat exchanger. In this way, the increase of the cooling water tank volume can be minimized. To design an air-water combined cooling system, the steam condensation characteristics of an air-cooling heat exchanger tube was calculated using a CFX code. The results show that the air velocities around the tube at the steam inlet/outlet regions are quite different with each other. Therefore, dense installation of thermocouples at the tube bottom region is required to measure the steam condensation in the tube. Otherwise, the detection and measurement of steam condensation at the steam inlet region may be very difficult. The velocity distribution of air is not uniform and the distributions of air temperature and velocity around the heat exchanger tube are strongly asymmetric. In the design of the measurement system of the test facility, the problems mentioned above should be considered.

  5. Analysis of Steam Condensation in a Finned Tube of Air-Water Combined Cooling System

    A Passive Auxiliary Feedwater System (PAFS) is one of the passive cooling systems of the existing power plant and the operating period is 8 hours because of the limited capacity of the cooling water tank. Therefore, to increase the operating period from 8 to 72 hours for an existing PAFS, the capacity of the cooling water tank should be increased up to 3-4 times. To resolve the excessive increase of the cooling tank volume in water cooling systems, an air-water combined passive cooling system is proposed. In this combined cooling system, the core cooling during the initial stage of an accident having high decay power depends on the water cooling systems such as PAFS. For the later phase of an accident, an air-cooling system is applied to the core cooling. In the operation of the air-cooling system, the steam from the cooling water tank of the PAFS is condensed and recirculated to the cooling water tank by an air-cooling heat exchanger. In this way, the increase of the cooling water tank volume can be minimized. To design an air-water combined cooling system, the steam condensation characteristics of an air-cooling heat exchanger tube was calculated using a CFX code. The results show that the air velocities around the tube at the steam inlet/outlet regions are quite different with each other. Therefore, dense installation of thermocouples at the tube bottom region is required to measure the steam condensation in the tube. Otherwise, the detection and measurement of steam condensation at the steam inlet region may be very difficult. The velocity distribution of air is not uniform and the distributions of air temperature and velocity around the heat exchanger tube are strongly asymmetric. In the design of the measurement system of the test facility, the problems mentioned above should be considered

  6. Cooling water treatment for heavy water project (Paper No. 6.9)

    With minor exceptions, water is the preferred industrial medium for the removal of unwanted heat from process systems. The application of various chemical treatments is required to protect the system from water related and process related problems of corrosion, scale and deposition and biofouling. The paper discusses the cooling water problems for heavy water industries along with the impact caused by associated fertilizer units. (author). 6 figs

  7. 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

  8. New Directions for Evaporative Cooling Systems.

    Robison, Rita

    1981-01-01

    New energy saving technology can be applied to older cooling towers; in addition, evaporative chilling, a process that links a cooling tower to the chilling equipment, can reduce energy use by 80 percent. (Author/MLF)

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

    Saari, Heini-Emilia

    2015-01-01

    This Master’s 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...

  10. Pink-Beam, Highly-Accurate Compact Water Cooled Slits

    Advanced Design Consulting, Inc. (ADC) has designed accurate compact slits for applications where high precision is required. The system consists of vertical and horizontal slit mechanisms, a vacuum vessel which houses them, water cooling lines with vacuum guards connected to the individual blades, stepper motors with linear encoders, limit (home position) switches and electrical connections including internal wiring for a drain current measurement system. The total slit size is adjustable from 0 to 15 mm both vertically and horizontally. Each of the four blades are individually controlled and motorized. In this paper, a summary of the design and Finite Element Analysis of the system are presented

  11. What causes cooling water temperature gradients in forested stream reaches?

    G. Garner

    2014-06-01

    Full Text Available Previous studies have suggested that shading by riparian vegetation may reduce maximum water temperature and provide refugia for temperature sensitive aquatic organisms. Longitudinal cooling gradients have been observed during the daytime for stream reaches shaded by coniferous trees downstream of clear cuts, or deciduous woodland downstream of open moorland. However, little is known about the energy exchange processes that drive such gradients, especially in semi-natural woodland contexts, and in the absence of potentially confounding cool groundwater inflows. To address this gap, this study quantified and modelled variability in stream temperature and heat fluxes along an upland reach of the Girnock Burn (a tributary of the Aberdeenshire Dee, Scotland where riparian landuse transitions from open moorland to semi-natural forest. Observations were made along a 1050 m reach using a spatially-distributed network of ten water temperature micro-loggers, three automatic weather stations and >200 hemispherical photographs, which were used to estimate incoming solar radiation. These data parameterised a high-resolution energy flux model, incorporating flow-routing, which predicted spatio-temporal variability in stream temperature. Variability in stream temperature was controlled largely by energy fluxes at the water column–atmosphere interface. Predominantly net energy gains occurred along the reach during daylight hours, and heat exchange across the bed-water column interface accounted for 1h. Temperature gradients were not generated by cooling of stream water, but rather by a combination of reduced rates of heating in the woodland reach and advection of cooler (overnight and early morning water from the upstream moorland catchment. Longitudinal thermal gradients were indistinct at night and on days when net radiation gains were low (under over-cast skies, thus when changes in net energy gains or losses did not vary significantly in space and time

  12. What causes cooling water temperature gradients in forested stream reaches?

    Garner, G.; Malcolm, I. A.; Sadler, J. P.; Hannah, D. M.

    2014-06-01

    Previous studies have suggested that shading by riparian vegetation may reduce maximum water temperature and provide refugia for temperature sensitive aquatic organisms. Longitudinal cooling gradients have been observed during the daytime for stream reaches shaded by coniferous trees downstream of clear cuts, or deciduous woodland downstream of open moorland. However, little is known about the energy exchange processes that drive such gradients, especially in semi-natural woodland contexts, and in the absence of potentially confounding cool groundwater inflows. To address this gap, this study quantified and modelled variability in stream temperature and heat fluxes along an upland reach of the Girnock Burn (a tributary of the Aberdeenshire Dee, Scotland) where riparian landuse transitions from open moorland to semi-natural forest. Observations were made along a 1050 m reach using a spatially-distributed network of ten water temperature micro-loggers, three automatic weather stations and >200 hemispherical photographs, which were used to estimate incoming solar radiation. These data parameterised a high-resolution energy flux model, incorporating flow-routing, which predicted spatio-temporal variability in stream temperature. Variability in stream temperature was controlled largely by energy fluxes at the water column-atmosphere interface. Predominantly net energy gains occurred along the reach during daylight hours, and heat exchange across the bed-water column interface accounted for 1h. Temperature gradients were not generated by cooling of stream water, but rather by a combination of reduced rates of heating in the woodland reach and advection of cooler (overnight and early morning) water from the upstream moorland catchment. Longitudinal thermal gradients were indistinct at night and on days when net radiation gains were low (under over-cast skies), thus when changes in net energy gains or losses did not vary significantly in space and time, and heat advected

  13. Method to reduce the 131 iodine content in the cooling water of a pressurized water reactor

    Due to once-through or repeated power production in PWR before the planned shut-down to the condensation of the coolant in the fuel rods, iodine 131 is dissolved up by the condensed water and is introduced into the cooling circuit by leaks in the fuel rods. This can lead to iodine saturation. A decontamination equipment placed in the cooling circuit absorbs the I 131 after shut-down until the initial equilibrium concentration is reached. (DG)

  14. 77 FR 73056 - Initial Test Programs for Water-Cooled Nuclear Power Plants

    2012-12-07

    ... COMMISSION Initial Test Programs for Water-Cooled Nuclear Power Plants AGENCY: Nuclear Regulatory Commission...-Cooled Nuclear Power Plants.'' This guide describes the general scope and depth that the staff of the NRC considers acceptable for Initial Test Programs (ITPs) for light water cooled nuclear power plants....

  15. Environmental compatible cooling water treatment chemicals; Umweltvertraegliche Chemikalien in der Kuehlwasserkonditionierung

    Gartiser, S.; Urich, E.

    2002-02-01

    In Germany about 32 billion m{sup 3}/a cooling water are discharged from industrial plants and power industry. These are conditioned partly with biocides, scaling and corrosion inhibitors. Within the research project the significance of cooling water chemicals was evaluated, identifying the chemicals from product information, calculating their loads from consumption data of more than 180 cooling plants and investigating the basic data needed for an environmental hazard assessment. Additionally the effects of cooling water samples and products were determined in biological test systems. Batch tests were performed under defined conditions in order to measure the inactivation of cooling water biocides. (orig.)

  16. Seismic design of ITER component cooling water system-1 piping

    The successful performance of ITER machine very much depends upon the effective removal of heat from the in-vessel components and other auxiliary systems during Tokamak operation. This objective will be accomplished by the design of an effective Cooling Water System (CWS). The optimized piping layout design is an important element in CWS design and is one of the major design challenges owing to the factors of large thermal expansion and seismic accelerations; considering safety, accessibility and maintainability aspects. An important sub-system of ITER CWS, Component Cooling Water System-1 (CCWS-1) has very large diameter of pipes up to DN1600 with many intersections to fulfill the process flow requirements of clients for heat removal. Pipe intersection is the weakest link in the layout due to high stress intensification factor. CCWS-1 piping up to secondary confinement isolation valves as well as in-between these isolation valves need to survive a Seismic Level-2 (SL-2) earthquake during the Tokamak operation period to ensure structural stability of the system in the Safe Shutdown Earthquake (SSE) event. This paper presents the design, qualification and optimization of layout of ITER CCWS-1 loop to withstand SSE event combined with sustained and thermal loads as per the load combinations defined by ITER and allowable limits as per ASME B31.3. This paper also highlights the Modal and Response Spectrum Analyses done to find out the natural frequency and system behavior during the seismic event. (author)

  17. Water cooled metal optics for the Advanced Light Source

    The program for providing water cooled metal optics for the Advanced Light Source at Berkeley is reviewed with respect to fabrication and metrology of the surfaces. Materials choices, surface figure and smoothness specifications, and metrology systems for measuring the plated metal surfaces are discussed. Results from prototype mirrors and grating blanks will be presented, which show exceptionally low microroughness and mid-period error. We will briefly describe out improved version of the Long Trace Profiler, and its importance to out metrology program. We have completely redesigned the mechanical, optical and computational parts of the profiler system with the cooperation of Peter Takacs of Brookhaven, Continental Optical, and Baker Manufacturing. Most important is that one of our profilers is in use at the vendor to allow testing during fabrication. Metrology from the first water cooled mirror for an ALS beamline is presented as an example. The preplating processing and grinding and polishing were done by Tucson Optical. We will show significantly better surface microroughness on electroless nickel, over large areas, than has been reported previously

  18. LOCA features peculiar to an integral water cooled PWR

    LOCA initiated by a guillotine break of the pressurizer surge line has been considered in the paper. The failure of two emergency core cooling system (ECCS) trains was also postulated, that turns the considered accident sequence into a beyond the design basis (BDB) class. Basic design characteristics of the ABV reactor and the containment system are presented as well as the factors of much importance to the accident progression. SCDAP/RELAP5/MOD3.1 was used as the computer code for the simulation of reactor and containment system behavior in the course of the accident. Since a noncondensable driven pressurizing system was employed in the reactor design, the presence of dissolved nitrogen in the primary water was taken into account in calculations. The important feature of the simulated accident is the primary system refilling with the water of pressure suppression pool driven by the pressure difference between containment system compartments. (author)

  19. Optimum hot water temperature for absorption solar cooling

    Lecuona, A.; Ventas, R.; Venegas, M.; Salgado, R. [Dpto. Ingenieria Termica y de Fluidos, Universidad Carlos III de Madrid, Avda. Universidad 30, 28911 Leganes, Madrid (Spain); Zacarias, A. [ESIME UPA, IPN, Av. de las Granjas 682, Col. Santa Catarina, 02550, D.F. Mexico (Mexico)

    2009-10-15

    The hot water temperature that maximizes the overall instantaneous efficiency of a solar cooling facility is determined. A modified characteristic equation model is used and applied to single-effect lithium bromide-water absorption chillers. This model is based on the characteristic temperature difference and serves to empirically calculate the performance of real chillers. This paper provides an explicit equation for the optimum temperature of vapor generation, in terms of only the external temperatures of the chiller. The additional data required are the four performance parameters of the chiller and essentially a modified stagnation temperature from the detailed model of the thermal collector operation. This paper presents and discusses the results for small capacity machines for air conditioning of homes and small buildings. The discussion highlights the influence of the relevant parameters. (author)

  20. Analysis of Cooling and Heating of Water with Flat-plate Solar Radiators

    Balen, Igor; Soldo, Vladimir; Kennedy, David

    2003-01-01

    Extensive analysis of flat-plate radiative panels operation using average hourly weather data for a maritime climate region was performed. The panels are integrated in the space ventilation system with air-cooling by means of a cold-water coil. Their primary function is to prepare sufficient quantity of cold water, integrating radiative and convective cooling, that is collected in the cold-water tank during the nighttime operation. That cold water is used for cooling of the air during daytime...

  1. Chemistry control strategies for a supercritical water-cooled reactor

    The long-term viability of any Generation IV Supercritical Water-cooled Reactor (SCWR) concept depends on the ability of reactor designers and operators to predict and control water chemistry to minimize corrosion and corrosion product transport. Currently, SCWR material testing is being carried out using a limited range of water chemistries to establish the dependencies of the corrosion behavior on parameters such as water temperature and dissolved oxygen concentration. Once a final suite of candidate alloys is identified, more detailed, longer term testing will be needed under water chemistry regimes expected to be used in the SCWR. Prior to these tests, it will be necessary to identify proposed water chemistry regimes for the SCWR, and provide expected ranges for the key parameters. The direct-cycle design proposed for various SCWR concepts take advantage of the extensive operating experience world-wide of fossil-fired SCW power plants. Conceptually, the SCWR replaces the fossil-fired boiler with the reactor core (pressure vessel or pressure tube); the concept is broadly similar to that of a boiling water reactor. Current fossil-fired SCW power plants use either an all-volatile treatment or oxygenated water treatment for the feedwater systems. While the optimal water chemistry for a SCWR is yet to be determined, the monitored parameters are likely to be the same as those in existing fossil-fired and nuclear power plants: pH; conductivity, and concentrations of O2, H2, additives, impurities, corrosion and activation products. Monitoring will be required at many of the same components: feedwater, main 'steam', drains, pump outlets, condenser hotwell, and purification inlets and outlets. This paper outlines the strategy being used to develop a water chemistry regime for a CANDU® SCWR. It describes the key areas identified for chemistry monitoring and control: a) the reactor core, where materials are subjected to irradiation and high temperature, b

  2. Candidate Materials Evaluation for Supercritical Water-Cooled Reactor

    Final technical report on the corrosion, stress corrosion cracking, and radiation response of candidate materials for the supercritical water-cooled reactor concept. The objective of the proposed research was to investigate degradation of materials in the supercritical water environment (SCW). First, representative alloys from the important classes of candidate materials were studied for their corrosion and stress-corrosion cracking (SCC) resistance in supercritical water. These included ferritic/martensitic (F/M) steels, austenitic stainless steels, and Ni-base alloys. Corrosion and SCC tests were conducted at various temperatures and exposure times, as well as in various water chemistries. Second, emerging plasma surface modification and grain boundary engineering technologies were applied to modify the near surface chemistry, microstructure, and stress-state of the alloys prior to corrosion testing. Third, the effect of irradiation on corrosion and SCC of alloys in the as-received and modified/engineered conditions were examined by irradiating samples using high-energy protons and then exposing them to SCW

  3. Optimization of operational water chemistry for supercritical-water cooled reactor

    The paper summaries the experimental results obtained within the project 'PRAMEK'. The project is focused on the study of the compatibility of the construction material of fossil-fueled supercritical water cooled power plants and water chemistry, that is currently used and optimization the dosing of the chemical species to the working circuit. The experience from the project enables to evaluate the water chemistry for Supercritical water cooled reactor (SCWR) and the transfer of the operational experience to the operation of the future nuclear power plant. The used materials are candidate for the SCWR and used in the industrial scale in the Ledvice power plant (fossil fuelled) with the supercritical parameters of the medium. It illustrates the future behaviour in the SCWR plant. The influence of the irradiation will be tested in future within the supercritical water loop in the reactor LVR-15. (author)

  4. Stair Column Tower

    Branch, Lauren N

    2013-01-01

    This set of drawings, paintings, and photographs explores the realms of knowledge and experience in architecture through analytical and perceptual means. In other words, how physical, material considerations inform the experience of moving through space, the perception of space, and the memory of place. These themes and questions are considered through the design of an observation tower that punctuates the ambiguous joint between land and water, earth and sky on the southwestern most point on...

  5. Management of a water leak on actively cooled fusion devices

    ITER will be the most important machine equipped with actively cooled plasma facing components (PFCs). In case of abnormal events during a discharge, the PFC will be submitted to localized transient phenomena (high power densities, run away electrons, etc.), leading, in the worst case, to the degradation of the PFC wall and possibly to a water leak. In any case, a leak will have important consequences for the PFCs and equipment located in the vacuum vessel or connected to the ports such as seals, pumping systems or diagnostics. Considerable experience of these events has been gained at Tore Supra over a period of more than 10 years [J.J. Cordier, Ten years of maintenance on Tore Supra actively cooled components, in: Proceedings of the 21th Symp. of Fusion Technology (SOFT), Madrid, Spain, September, 2000.], which will be useful for the next step machines. This paper describes for each leak size type the procedures for maintaining save conditions in the vacuum vessel. It also presents the methods used at Tore Supra to drain-off the primary loop circuits and to identify the leaky PFC

  6. Saving of drinking water in cooling system at Aq aba Thermal Power Station

    This paper discussing a new modification, design and implementation to the existing cooling water system of boiler drum continuous blow down water at Aq aba Thermal Power Stations to eliminate drinking water consumption as a coolant medium

  7. Entrainment of ichthyoplankton and larval fishes during cooling water withdrawal

    Plantonic fish eggs and larvae are entrained into the Savannah River Plant (SRP) pumping system as Savannah River water is withdrawn for cooling purposes. The American shad contributed 96% of the planktonic fish eggs collected in the Savannah River. Eggs were rare in plankton samples from the intake canals and were assumed to have settled to the bottom as current velocity was reduced in the canal entrance. An estimated 72 million fish eggs were transported past the intake canals. Assuming ''worst case conditions,'' 6.8 million eggs (9.5%) could have been lost due to entrainment. Blueback herring comprised nearly one-half of the 216 million fish larvae susceptible to impact. Spotted sucker and black crappie were also common among the 22 species of fish larvae collected. An estimated 19.6 million (9.1%) fish larvae could have been entrained under ''worst case conditions''

  8. Thermal-hydraulic limitations on water-cooled limiters

    An assessment of the cooling requirements for fusion reactor components, such as the first wall and limiter/divertor, was carried out using pressurized water as the coolant. In order to establish the coolant operating conditions, a survey of the literature on departure from nucleate boiling, critical heat flux, asymmetrical heating and heat transfer augmentation techniques was carried out. The experimental data and the empirical correlations indicate that thermal protection for the fusion reactor components based on current design concepts can be provided with an adequate margin of safety without resorting to either high coolant velocities, excessive coolant pressures, or heat transfer augmentation techniques. If, however, the future designs require heat transfer enhancement techniques, experimental verification would be necessary since no data on heat transfer augmentation techniques exist for complex geometries, especially under asymmetrically heated conditions. Since the data presented herein concern primarily thermal protection, the final design should consider other factors such as thermal stresses, temperature limits, and fatigue

  9. Effect of Mixed Corrosion Inhibitors in Cooling Water System

    Dina Raheem

    2011-01-01

    Full Text Available The effect of mixed corrosion inhibitors in cooling system was evaluated by using carbon steel specimens and weight loss analysis. The carbon steel specimens immersed in mixture of sodium phosphate (Na2 HPO4 used as corrosion inhibitor and sodium glocunate (C6 H11 NaO7 as a scale dispersant at different concentrations (20,40, 60, 80 ppm and at different temperature (25,50,75 and 100ºC for (1-5 days. The corrosion inhibitors efficiency was calculated by using uninhibited and inhibited water to give 98.1%. The result of these investigations indicate that the corrosion rate decreases with the increase the corrosion inhibitors concentration at 80 ppm and at 100ºC for 5 days, (i.e, corrosion rate= 0.014gmd.

  10. B Plant Cooling Water stream-specific report

    The proposed wastestream designation for the B Plant Cooling Water (CBC) waste stream is that the stream is not a dangerous waste, pursuant to the Washington (State) Administrative Code (WAC) 173-303, Dangerous Waste Regulations. This proposed designation, made by applying a combination of process knowledge and sample data for the CBC (October 1989 to March 1990), was used to determine if the effluent contains a listed dangerous waste (WAC 173-303-080). Sampling data alone is used to compare to the dangerous waste criteria (WAC 173-303-100) and dangerous waste characteristics (WAC 173-303-090). Sample data for the CBC operation was from the October 1989 to March 1990 timeframe that is based on the Liquid Effluent Study Characterization Data (WHC-EP-0355). 21 refs., 7 figs., 10 tabs

  11. Detecting and mitigating aging in component cooling water systems

    The time-dependent effects of aging on component cooling water (CCW) systems in nuclear power plants has been studied and documented as part of a research program sponsored by the US Nuclear Regulatory Commission. It was found that age related degradation leads to failures in the CCW system which can result in an increase in system unavailability, if not properly detected and mitigated. To identify effective methods of managing this degradation, information on inspection, monitoring, and maintenance practices currently available was obtained from various operating plants and reviewed. The findings were correlated with the most common aging mechanisms and failure modes, and a compilation of aging detection and mitigation practices was formulated. This paper discusses the results of this work

  12. Flow-induced vibration of component cooling water heat exchangers

    This paper presents an evaluation of flow-induced vibration problems of component cooling water heat exchangers in one of Taipower's nuclear power stations. Specifically, it describes flow-induced vibration phenomena, tests to identify the excitation mechanisms, measurement of response characteristics, analyses to predict tube response and wear, various design alterations, and modifications of the original design. Several unique features associated with the heat exchangers are demonstrated, including energy-trapping modes, existence of tube-support-plate (TSP)-inactive modes, and fluidelastic instability of TSP-active and -inactive modes. On the basis of this evaluation, the difficulties and future research needs for the evaluation of heat exchangers are identified. 11 refs., 19 figs., 3 tabs

  13. Evaporative cooling and water balance during flight in birds.

    Torre-Bueno, J R

    1978-08-01

    The rate of evaporative cooling was calculated from the rate of mass loss in starlings (Sturnus vulgaris) during 90 min flights in a wind-tunnel. Evaporative heat loss ranged from 5% of the metabolic rate at -5 degrees C to 19% of the metabolic rate at 29 degrees C. Radiation and convection accounted for the balance of the heat loss. On average, starlings dehydrated during flights at all temperatures above 7 degrees C. The comparison of these results with data from field studies, which indicate that long-distance migrants do not dehydrate, suggests that migrants may maintain water balance by ascending to colder air in which convection carries off most of the heat produced. PMID:702042

  14. BIOFILM FORMATION ON BRASS COUPONS EXPOSED TO COOLING WATER

    Lutterbach M.T.S.

    1997-01-01

    Full Text Available Brass coupons were installed in a bypass in an industrial cooling water that uses seawater. The metal samples were removed at 15, 30, 45, and 60-day intervals for quantitative and qualitative analyses of the microorganisms constituting the biofilm adhering to the metal surface. After 15 days of exposure, a biofilm had already been generated which contained aerobic and anaerobic microorganisms. The aerobic bacteria were the most stable in relation to quantity, followed by the fungi. Anaerobic microorganisms, as well as sulfate-reducing bacteria, were present at higher concentrations. Variations in sulfide contents were observed in the biofilm. Analysis by scanning electron microscopy revealed microalgae, bacteria, filaments, and corrosion products as constituents of the biofilm adhering to the surface of the metal. After the biofilms were scraped off the brass samples, evidence of corrosion was observed on the metal surface

  15. Degradation of zirconium alloys in water-cooled nuclear reactors

    Zirconium alloys are used almost exclusively as fuel cladding, and other structural components in the cores of water-cooled nuclear reactors. This choice was largely forced on the designers by constraints to economize on neutron absorption. Among the low neutron cross-section metals (Be, Mg, Al, Si, Zr), zirconium is the only one with both adequate corrosion resistance to --3000C water, and adequate strength and ductility. However, it does suffer degradation by a number of routes; corrosion from the outside; corrosion and stress corrosion cracking from the inside; and irradiation induced embrittlement and delayed hydride cracking from within. These various modes of degradation are discussed here. Despite these possible modes of failure the in-reactor behaviour of zirconium alloy fuel cladding and other components has been generally good. However, the desire to increase fuel burnup in order to reduce fuelling costs, and a trend to higher water temperature in reactors, is pushing the zirconium alloy components to the limits of the endurance. Some discussion of future trends is given

  16. Water pollution of ammonia cooling installations; Verontreiniging met water van ammoniak-koelinstallaties

    Skaerbaek Nielsen, P. [Danfoss Industrial Refrigeration, Hasselager (Denmark)

    2001-09-01

    Danfoss Industrial Refrigeration claims to have the knowledge to help businesses and industry in saving energy and to decrease maintenance cost of cooling systems. Part of its knowledge and experiences in this field is laid down in a technical document 'Effects of Water Contamination in Ammonia Refrigeration Systems'. A summary of the document is presented in this article. 2 refs.

  17. Loss of coolant accident analysis of supercritical water-cooled reactor fuel qualification test loop

    The supercritical water-cooled reactor fuel qualification test (SCWR-FQT) intends to test a small scale fuel assembly under supercritical water environment in a research reactor. The modified ATHLET code was applied to model the supercritical water-cooled experimental loop containing this fuel assembly and to perform the calculation analysis of the loss of coolant accident induced by the coolant pipe break. The results indicate that the design of existing safety system can practically ensure the effective cooling of the fuel rod experimental section in the accident scenario. The results also show that the modified ATHLET code has good suitability in simulation of supercritical water-cooled system. (authors)

  18. Advanced applications of water cooled nuclear power plants

    By August 2007, there were 438 nuclear power plants (NPPs) in operation worldwide, with a total capacity of 371.7 GW(e). Further, 31 units, totaling 24.1 GW(e), were under construction. During 2006 nuclear power produced 2659.7 billion kWh of electricity, which was 15.2% of the world's total. The vast majority of these plants use water-cooled reactors. Based on information provided by its Member States, the IAEA projects that nuclear power will grow significantly, producing between 2760 and 2810 billion kWh annually by 2010, between 3120 and 3840 billion kWh annually by 2020, and between 3325 and 5040 billion kWh annually by 2030. There are several reasons for these rising expectations for nuclear power: - Nuclear power's lengthening experience and good performance: The industry now has more than 12 000 reactor years of experience, and the global average nuclear plant availability during 2006 reached 83%; - Growing energy needs: All forecasts project increases in world energy demand, especially as population and economic productivity grow. The strategies are country dependent, but usually involve a mix of energy sources; - Interest in advanced applications of nuclear energy, such as seawater desalination, steam for heavy oil recovery and heat and electricity for hydrogen production; - Environmental concerns and constraints: The Kyoto Protocol has been in force since February 2005, and for many countries (most OECD countries, the Russian Federation, the Baltics and some countries of the Former Soviet Union and Eastern Europe) greenhouse gas emission limits are imposed; - Security of energy supply is a national priority in essentially every country; and - Nuclear power is economically competitive and provides stability of electricity price. In the near term most new nuclear plants will be evolutionary water cooled reactors (Light Water Reactors (LWRs) and Heavy Water Reactors (HWRs), often pursuing economies of scale. In the longer term, innovative designs that

  19. FORIDA Towers - Analysis of UHPFRC Tower

    Jensen, Lars Rom; Dollerup, Niels; Damkilde, Lars

    This report is a detailed analysis of the UHPFRC tower in the hybrid wind turbine tower. The analysis of the UHPFRC tower includes a validation of the Service Limit State (SLS) for both characteristic and frequent load cases, the Ultimate Limit State (ULS) and the Fatigue load state. The analysis...

  20. A Synergistic Combination of Advanced Separation and Chemical Scale Inhibitor Technologies for Efficient Use of Imparied Water As Cooling Water in Coal-based Power Plants

    Jasbir Gill

    2010-08-30

    commercial product commonly used for silica/silicate control. Additional pilot cooling tower testing confirmed the bench study. We also developed a molecule to inhibit calcium carbonate precipitation and calcium sulfate precipitation at high supersaturations. During Phase 3, a long-term test of the EDI system and scale inhibitors was done at Nalco's cooling tower water testing facility, producing 850 gallons of high purity water (90+% salt removal) at a rate of 220 L/day. The EDI system's performance was stable when the salt concentration in the concentrate compartment (i.e. the EDI waste stream) was controlled and a CIP was done after every 48 hours of operation time. A combination of EDI and scale inhibitors completely eliminated blowdown discharge from the Pilot cooling Tower. The only water-consumption came from evaporation, CIP and EDI concentrate. Silica Inhibitor was evaluated in the field at a western coal fired power plant.

  1. Development of the water cooled lithium lead blanket for DEMO

    Aubert, J., E-mail: julien.aubert@cea.fr [CEA-Saclay, DEN/DANS/DM2S/SEMT/BCCR, 91191 Gif Sur Yvette Cedex (France); Aiello, G.; Jonquères, N. [CEA-Saclay, DEN/DANS/DM2S/SEMT/BCCR, 91191 Gif Sur Yvette Cedex (France); Li Puma, A. [CEA-Saclay, DEN/DANS/DM2S/SERMA/LPEC, 91191 Gif Sur Yvette Cedex (France); Morin, A.; Rampal, G. [CEA-Saclay, DEN/DANS/DM2S/SEMT/BCCR, 91191 Gif Sur Yvette Cedex (France)

    2014-10-15

    Highlights: • The WCLL blanket design has been modified to adapt it to the 2012 EFDA DEMO specifications. • Preliminary CAD design of the equatorial outboard module of the WCLL blanket has been developed for DEMO. • Finite elements analyses have been carried out in order to assess the module thermal behavior in the straight part of the module. - Abstract: The water cooled lithium lead (WCLL) blanket, based on near-future technology requiring small extrapolation from present-day knowledge both on physical and technological aspect, is one of the breeding blanket concepts considered as possible candidates for the EU DEMOnstration power plant. In 2012, the EFDA agency issued new specifications for DEMO: this paper describes the work performed to adapt the WCLL blanket design to those specifications. Relatively small modules with straight surfaces are attached to a common Back Supporting Structure housing feeding pipes. Each module features reduced activation ferritic-martensitic steel as structural material, liquid Lithium-Lead as breeder, neutron multiplier and carrier. Water at typical Pressurized Water Reactors (PWR) conditions is chosen as coolant. A preliminary design of the equatorial outboard module has been achieved. Finite elements analyses have been carried out in order to assess the module thermal behavior. Two First Wall (FW) concepts have been proposed, one favoring the thermal efficiency, the other favoring the manufacturability. The Breeding Zone has been designed with C-shaped Double-Walled Tubes in order to minimize the Water/Pb-15.7Li interaction likelihood. The priorities for further development of the WCLL blanket concept are identified in the paper.

  2. Water cooling system for an air-breathing hypersonic test vehicle

    Petley, Dennis H.; Dziedzic, William M.

    1993-01-01

    This study provides concepts for hypersonic experimental scramjet test vehicles which have low cost and low risk. Cryogenic hydrogen is used as the fuel and coolant. Secondary water cooling systems were designed. Three concepts are shown: an all hydrogen cooling system, a secondary open loop water cooled system, and a secondary closed loop water cooled system. The open loop concept uses high pressure helium (15,000 psi) to drive water through the cooling system while maintaining the pressure in the water tank. The water flows through the turbine side of the turbopump to pump hydrogen fuel. The water is then allowed to vent. In the closed loop concept high pressure, room temperature, compressed liquid water is circulated. In flight water pressure is limited to 6000 psi by venting some of the water. Water is circulated through cooling channels via an ejector which uses high pressure gas to drive a water jet. The cooling systems are presented along with finite difference steady-state and transient analysis results. The results from this study indicate that water used as a secondary coolant can be designed to increase experimental test time, produce minimum venting of fluid and reduce overall development cost.

  3. Status of advanced technology and design for water cooled reactors: Heavy water reactors

    In 1987 the IAEA established the International Working Group on Advanced Technologies for Water-Cooled Reactors (IWGATWR). Within the framework of the IWGATWR the IAEA Technical Report on Status of Advanced Technology and Design for Water Cooled Reactors, Part I: Light Water Reactors and Part II: Heavy Water Reactors, has been undertaken to document the major current activities and trends of technological improvement and development for future water reactors. Part I of the report dealing with Light Water Reactors (LWRs) was published in 1988 (IAEA-TECDOC-479). Part II of the report covers Heavy Water Reactors (HWRs) and has now been prepared. This report is based largely upon submissions from Member States. It has been supplemented by material from the presentations at the IAEA Technical Committee and Workshop on Progress in Heavy Water Reactor Design and Technology held in Montreal, Canada, December 6-9, 1988. It is hoped that this part of the report, containing the status of advanced heavy water reactor technology up to 1988 and ongoing development programmes will aid in disseminating information to Member States and in stimulating international cooperation. Refs, figs and tabs

  4. Integration of Small Solar Tower Systems Into Distributed Power Islands

    One of the short-term priorities for renewable energies in Europe is their integration for local power supply into communities and energy islands (blocks of buildings, new neighborhoods in residential areas, shopping centers, hospitals, recreational areas, eco-parks, small rural areas or isolated ones such as islands or mountain communities). Following this strategy, the integration of small tower fields into so-called MIUS (Modular Integrated Utility Systems) is proposed. This application strongly influences field concepts leading to modular multi-tower systems able to more closely track demand, meet reliability requirements with fewer megawatts of installed power and spread construction costs over time after output has begun. In addition, integration into single-cycle high-efficiency gas turbines plus waste-heat applications clearly increments the solar share. The chief questions are whether solar towers can be redesigned for such distributed markets and the keys to their feasibility. This paper includes the design and performance analysis of a 1.36-MW plant and integration in the MIUS system, as well as the expected cost of electricity and a sensitivity analysis of the small tower plant's performance with design parameters like heliostats configuration and tower height. A practical application is analyzed for a shopping center with 85% power demand during day-time by using a hybrid solar tower and a gas turbine producing electricity and waste heat for hot water and heating and cooling of spaces. The operation mode proposed is covering night demand with power from the grid and solar-gas power island mode during 14 hours daytime with a maximum power production of 1.36 MW. (Author) 26 refs

  5. Integration of Small Solar tower Systems into Distributed Power Islands

    Romero, M.; Marcos, M. J.; Tellez, F. M.; Blanco, M.; Fernandez, V.; Baonza, F.; Berger, S. [Ciemat, Madrid (Spain)

    2000-07-01

    One of the short-term priorities for renewable energies in Europe is their integration for local power supply into communities and energy islands (blocks of buildings, new neighborhoods in residential areas, shopping centers, hospitals, recreational areas, eco-paks, small rural areas or isolated ones such as islands or mountain communities). Following this strategy, the integration of small tower fields into so-called MIUS (Modular Integrated Utility Systems) is proposed. This application strongly influences field concepts leadings to modular multi-tower systems able to more closely track demand, meet reliability requirements with fewer megawatts of installed power and spread construction costs over time after output has begum. In addition, integration into single-cycle high-efficiency gas turbines plus waste-heat applications clearly increments the solar share. The chief questions are whether solar towers can be redesigned for such distributed markets and the keys to their feasibility. This paper includes the design and performance analysis of a 1.36-MW plant and integration in the MIUS system, as well as the expected cost of electricity and a sensitivity analysis of the small tower plant's performance with design parameters like heliostat configuration and tower height. A practical application is analyzed for a shopping center with 85% power demand during day-time by using a hybrid solar tower and a gas turbine producing electricity and waste heat for hot water and heating and cooling of spaces. The operation mode proposed is covering night demand with power from the grid and solar-gas power island mode during 14 hours daytime with a maximum power production of 1.36 MW. (Author) 26 refs.

  6. Performance of materials in the component cooling water systems of pressurized water reactors

    The component cooling water (CCW) system provides cooling water to several important loads throughout the plant under all operating conditions. An aging assessment CCW systems in pressurized water reactors (PWRs) was conducted as part of Nuclear Plant Aging Research Program (NPAR) instituted by the US Nuclear Regulatory Commission. This paper presents some of the results on the performances of materials in respect of their application in CCW Systems. All the CCW system failures reported to the Nuclear Plant Reliability Data System (NPRDS) from January 1988 to June 1990 were reviewed; it is concluded that three of the main contributors to CCW system failures are valves, pumps, and heat exchangers. This study identified the modes and causes of failure for these components; most of the causes for the aging-related failures could be related to the performance of materials. Also, in this paper the materials used for these components are reviewed, and there aging mechanisms under CCW system conditions are discussed

  7. Status of advanced technology and design for water cooled reactors: Light water reactors

    Water reactors represent a high level of performance and safety. They are mature technology and they will undoubtedly continue to be the main stream of nuclear power. There are substantial technological development programmes in Member States for further improving the technology and for the development of new concepts in water reactors. Therefore the establishment of an international forum for the exchange of information and stimulation of international co-operation in this field has emerged. In 1987 the IAEA established the International Working Group on Advanced Technologies for Water-Cooled Reactors (IWGATWR). Within the framework of IWGATWR the IAEA Technical Report on Status of Advanced Technology and Design for Water Cooled Reactors, Part I: Light Water Reactors and Part II: Heavy Water Reactors has been undertaken to document the major current activities and different trends of technological improvements and developments for future water reactors. Part I of the report dealing with LWRs has now been prepared and is based mainly on submissions from Member States. It is hoped that this part of the report, containing the status of advanced light water reactor design and technology of the year 1987 and early 1988 will be useful for disseminating information to Agency Member States and for stimulating international cooperation in this subject area. 93 refs, figs and tabs

  8. Analysis of Ion Exchange Resin Waste of RSG-GAS Primary Cooling Water Purification System

    The ion exchange resin of the primary cooling water purification system serves to remove primary cooling water impurities to keep primary cooling water quality at the specified level. To identify the water impurities caught by ion exchange resin, it has been performed analysis of waste ion exchange resin coming from the primary cooling water purification system. Analysis was performed by taking waste ion exchange resin sample which will be sent to Centre for Radioactive Waste Technology (PTLR). Then the sample was counted with gamma spectrometer with HPGe detector. It showed that the identified nuclides were: Co-60, Cs-137, Mn-54, Zn-65 and Sb-124, which were long and medium half-lived primary cooling water impurities. (author)

  9. Process and device for processing used fuel elements of water-cooled nuclear reactors

    The fuel elements are transported dry in a transport container to an opening into a hot cell. A fuel element manipulator takes the fuel elements from the transport container and moves them to a handover shaft into a fuel element storage pond filled with water. The manipulator lowers the fuel element into a fixed cooling container, where it is first cooled, before it is finally deposited in the storage basin. The cooling container has special water cooling and is immersed in the water of the storage pond. (DG)

  10. Mitigation of hydrogen hazards in water cooled power reactors

    Past considerations of hydrogen generated in containment buildings have tended to focus attention on design basis accidents (DBAs) where the extent of the in-core metal-water reaction is limited at low values by the operation of the emergency core cooling systems (ECCS). The radiolysis of water in the core and in the containment sump, together with the possible corrosion of metals and paints in the containment, are all relatively slow processes. Therefore, in DBAs the time scale involved for the generation of hydrogen allows sufficient time for initiation of measures to control the amount of hydrogen in the containment atmosphere and to prevent any burning. Provisions have been made in most plants to keep the local hydrogen concentration below its flammability limit (4% of volume) by means of mixing devices and thermal recombiners. Severe accidents, involving large scale core degradation and possibly even core concrete interactions, raise the possibility of hydrogen release rates greatly exceeding the capacity of conventional DBA hydrogen control measures. The accident at Three Mile Island illustrated the potential of unmitigated hydrogen accumulation to escalate the potential consequences of a severe accident. In a severe accident scenario, local high hydrogen concentrations can be reached in a short time, leading to flammable gas mixtures in containment. Another possibility is that local high steam concentrations will initially create an inert atmosphere and prevent burning for a limited time. While such temporary inerting provides additional time for mixing (dilution) of the hydrogen with containment air, depending on the quantity of hydrogen released, it prevents early intervention by deliberate ignition and sets up conditions for more severe combustion hazards after steam condensation eventually occurs, e.g., by spray initiation or the long term cooling down of the containment atmosphere. As the foregoing example indicates, analysis of the hydrogen threat in

  11. Studies on corrosion inhibitors for the cooling water system at the Heavy Water Project, Kota

    The Heavy Water Project at Kota uses the water from the Rana Pratap Sagar Lake as coolant in the open recirculation system. In order to find suitable corrosion inhibitors for the above system, a series of laboratory experiments on corrosion inhibitors were carried out using the constructional materials of the cooling water system and a number of proprietary formulations and the results are tabulated. From the data thus generated through various laboratory experiments, the most useful ones have been recommended for application in practice. (author)

  12. Evaluation of a Design Concept for the Combined Air-water Passive Cooling PAFS+

    Bae, Sung Won; Kwon, Taesoon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    The APR+ system provides the Passive Auxiliary Feed-water System (PAFS) for the passive cooling capability. However, the current design requirement for working time for the PAFS is about 8 hours only. Thus, current working time of PAFS can not meet the required 72 hours cooling capability for the long term SBO situation. To meet the 72 hours cooling, the pool capacity should be almost 3∼4 times larger than that of current water cooling tank. In order to continue the PAFS operation for 72 hours, a new passive air-water combined cooling system is proposed. This paper provides the feasibility study on the combined passive air-water cooling system. Figure 1 and 2 show the conceptual difference of the PAFS and combined passive air-water cooling system, respectively. Simple performance evaluation of the passive air cooling heat exchanger has been conducted by the MARS calculation. For the postulated FLB scenario, 4800 heat exchanger tubes and 5 m/s air velocity are not sufficient to sustain the PCCT pool level for 72 hour cooling. Further works on the system design and performance enhancing plan are required to fulfill the 72 hours long term passive cooling.

  13. Evaluation of a Design Concept for the Combined Air-water Passive Cooling PAFS+

    The APR+ system provides the Passive Auxiliary Feed-water System (PAFS) for the passive cooling capability. However, the current design requirement for working time for the PAFS is about 8 hours only. Thus, current working time of PAFS can not meet the required 72 hours cooling capability for the long term SBO situation. To meet the 72 hours cooling, the pool capacity should be almost 3∼4 times larger than that of current water cooling tank. In order to continue the PAFS operation for 72 hours, a new passive air-water combined cooling system is proposed. This paper provides the feasibility study on the combined passive air-water cooling system. Figure 1 and 2 show the conceptual difference of the PAFS and combined passive air-water cooling system, respectively. Simple performance evaluation of the passive air cooling heat exchanger has been conducted by the MARS calculation. For the postulated FLB scenario, 4800 heat exchanger tubes and 5 m/s air velocity are not sufficient to sustain the PCCT pool level for 72 hour cooling. Further works on the system design and performance enhancing plan are required to fulfill the 72 hours long term passive cooling

  14. Use of Oriented Spray Nozzles to Set the Vapor-Air Flow in Rotary Motion in the Superspray Space of the Evaporative Chimney-Type Tower

    Dobrego, K. V.; Davydenko, V. F.; Koznacheev, I. A.

    2016-01-01

    The present paper considers the problem of upgrading the thermal efficiency of chimney-type evaporative cooling towers due to the rotary motion of the vapor-air flow in the superspray space. To set the vapor-air flow in rotary motion, we propose to use the momentum of the sprayed water. It has been shown that the existing parameters of spray nozzles permit setting up to 30% of the water flow momentum in translatory motion, which is enough for changing considerably the aerodynamics of the vapor-air flow in the superspray space and improving the operation of the cooling tower. The optimal angle of axial inclination of the spray cone has been estimated. Recommendations are given and problems have been posed for engineering realization of the proposed technologies in a chimney-type cooling tower.

  15. 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... Classification Codes (NAIC) Federal, State and Local Operators of steam 4911 and 493 221111, 221112,...

  16. Biological effects from discharge of cooling water from thermal power plants

    Results are reported for a Danish project on biological effects from discharge of cooling water from thermal power plants. The purpose of the project was to provide an up-to-date knowledge of biological effects of cooling water discharge and of organization and evaluation of recipient investigations in planned and established areas. (BP)

  17. State waste discharge permit application for cooling water and condensate discharges

    Haggard, R.D.

    1996-08-12

    The following presents the Categorical State Waste Discharge Permit (SWDP) Application for the Cooling Water and Condensate Discharges on the Hanford Site. This application is intended to cover existing cooling water and condensate discharges as well as similar future discharges meeting the criteria set forth in this document.

  18. State waste discharge permit application: 400 Area secondary cooling water

    This document constitutes the Washington Administrative Code 173-216 State Waste Discharge Permit Application that serves as interim compliance as required by the Consent Order DE 91NM-177, for the 400 Area Secondary Cooling Water stream. As part of the Hanford Federal Facility Agreement and Consent Order negotiations, the US Department of Energy, Richland Operations Office, the US Environmental Protection Agency, and the Washington State Department of Ecology agreed that liquid effluent discharges to the ground on the Hanford Site which affect groundwater or have the potential to affect groundwater would be subject to permitting under the structure of Chapter 173-216 (or 173-218 where applicable) of the Washington Administrative Code, the State Waste Discharge Permitting Program. As a result of this decision, the Washington State Department of Ecology and the US Department of Energy, Richland Operations Office entered in to Consent Order DE 91NM-177. The Consent Order DE 91NM-177 requires a series of permitting activities for liquid effluent discharges

  19. Modelling containment passive safety systems in advanced water cooled reactors

    Most designs of advanced passive reactors incorporate Passive Containment Cooling Systems (PCCS) relying on steam condensation to cope with possible pressure increase that would result in the case of a postulated accident. As a consequence, experimental and analytical research programmes have been launched worldwide to investigate new configurations and conditions involved in these new scenarios. This paper summarises the major outcomes of the joint research of CIEMAT, UPV, and UW in developing predictive models to address anticipated conditions in the Simplified Boiling Water Reactors (CIEMAT-UPV) and in the AP600 (CIEMAT-UW). Even though both models share some of their fundamental characteristics (such as being mass/heat transfer analogy based), samples of their validation against independent databases illustrate their intrinsic differences in formulation according to the scenarios addressed by each one. Relative importance of condensate film or gas mixture velocity are discussed, and the effect of key factors such as noncondensable gas presence and pressure are stated. Experimental data from University of Berkeley (UCB) and from University of Wisconsin - Madison (UW) will be used to support comparisons and discussions held in the paper. In short, this work demonstrates that heat/mass transfer analogy-based models, particularly those relying on diffusion film modelling to account for noncondensable gas presence, are extremely useful in test interpretation and result in good agreement with reliable databases. (author)

  20. Stability analysis of a heated channel cooled by supercritical water

    A simple model to study thermal-hydraulic stability of a heated cannel under supercritical conditions is presented. Single cannel stability analysis for the SCWR (Supercritical Water Cooled Reactor) design was performed. The drastic change of fluid density in the reactor core of a SCWR may induce DWO (Density Wave Oscillations) similar to those observed in BWRs. Due to the similarities between subcritical and supercritical systems we may treat the supercritical fluid as a pseudo two-phase system. Thus, we may extend the modeling approach often used for boiling flow stability analysis to supercritical pressure operation conditions. The model developed in this work take into account three regions: a heavy fluid region, similar to an incompressible liquid; a zone where a heavy fluid and a light fluid coexist, similar to two-phase mixture; and a light fluid region which behaves like superheated steam. It was used the homogeneous equilibrium model (HEM) for the pseudo boiling zone, and the ideal gas model for the pseudo superheated steam zone. System stability maps were obtained using linear stability analysis in the frequency domain. Two possible instability mechanisms are observed: DWO and excursive Ledinegg instabilities. Also, a sensitivity analysis showed that frictions in pseudo superheated steam zone, together with acceleration effect, are the most destabilizing effects. On the other hand, frictions in pseudo liquid zone are the most important stabilizing effect.

  1. Thermohydraulics of emergency core cooling in light water reactors

    This report, by a group of experts of the OECD-NEA Committee on the Safety of Nuclear Installations, reviews the current state-of-knowledge in the field of emergency core cooling (ECC) for design-basis, loss-of-coolant accidents (LOCA) and core uncover transients in pressurized- and boiling-water reactors. An overview of the LOCA scenarios and ECC phenomenology is provided for each type of reactor, together with a brief description of their ECC systems. Separate-effects and integral-test facilities, which contribute to understanding and assessing the phenomenology, are reviewed together with similarity and scaling compromises. All relevant LOCA phenomena are then brought together in the form of tables. Each phenomenon is weighted in terms of its importance to the course of a LOCA, and appraised for the adequacy of its data base and analytical modelling. This qualitative procedure focusses attention on the modelling requirements of dominant LOCA phenomena and the current capabilities of the two-fluid models in two-phase flows. This leads into the key issue with ECC: quantitative code assessment and the application of system codes to predict with a well defined uncertainty the behaviour of a nuclear power plant. This issue, the methodologies being developed for code assessment and the question of how good is good enough are discussed in detail. Some general conclusions and recommendations for future research activities are provided

  2. Hydrogen in water-cooled nuclear power reactors

    The Commission of the European Community (CEC) and the International Atomic Energy Agency (IAEA) decided in 1989 to update the state of the art concerning hydrogen in water cooled nuclear power reactors by commissioning a report which would review, all the available information to-date and make recommendations for the future. This joint report was prepared by committees formed by the IAEA and by the CEC. The aim of this report is to review the current understanding on the areas in which the research on hydrogen in LWR is conventionally presented, taking into account the results of the latest reported research developments. The main reactions through which hydrogen is produced are assessed together with their timings. An estimation of the amount of hydrogen produced by each reaction is given, in order to reckon their relative contribution to the hazard. An overview is then given of the state of knowledge of the most important phenomena taking place during its transport from the place of production and the phenomena which control the hydrogen combustion and the consequences of combustion under various conditions. Specific research work is recommended in each sector of the presented phenomena. The last topics reviewed in this report are the hydrogen detection and the prevent/mitigation of pressure and temperature loads on containment structures and structures and safety related equipment caused by hydrogen combustion

  3. Cooling systems addendum: capital and total generating cost studies

    These studies present the capital and total generating costs for alternate cooling systems designed for six power plants--1200 MWe (pressurized water reactor, boiling water reactor, high sulfur coal-fired, low sulfur coal-fired) plants and 800 MWe (low-sulfur coal-fired and high-sulfur coal-fired) plants. In these base-capital cost studies, all of the plants are designed using mechanical-draft evaporate towers. Alternate cooling systems evaluated include: once-through, fan-assisted natural-draft towers, and natural-draft towers. These alternative cooling systems represent viable designs from both an economic and engineering standpoint. The estimated total base construction costs for the six plants incorporating the alternate cooling systems are summarized. Capital cost and fuel cost vary with each cooling system as compared to the base case; i.e., mechanical-draft evaporative towers. The once-through cooling systems have the lowest capital cost of the alternate systems evaluated

  4. District cool water distribution; Reseau urbain et distribution d`eau glacee

    Schabaillie, D. [Ste Climespace (France)

    1997-12-31

    The city of Paris has developed several district cool water distribution networks (Climespace) for air conditioning purposes, one in the Halles district (central Paris) linked with the Louvre museum, one in the Opera district (with large department stores) and one in the east of paris (Bercy). Each of these networks has a cool water production plant, the one at the Halles producing also hot water and safety electric power. The characteristics of the equipment (heat pumps, refrigerating machinery, storage...) are described. The pipes are laid in the city sewage network, and the cool carrier is water. The various networks are centrally supervised at the Halles center

  5. Detailed Design of Cooling Water System for Cold Neutron Source in HANARO

    Kim, Bong Soo; Choi, Jung Woon; Kim, Y. K.; Wu, S. I.; Lee, Y. S

    2007-04-15

    To make cold neutron, a cryogenic refrigerator is necessary to transform moderator into cryogenic state so, thermal neutron is changed into cold neutron through heat transfer with moderator. A cryogenic refrigerator mainly consists of two apparatus, a helium compressor and a cold box which needs supply of cooling water. Therefore, cooling water system is essential to operate of cryogenic refrigerator normally. This report is mainly focused on the detailed design of the cooling water system for the HANARO cold neutron source, and describes design requirement, calculation, specification of equipment and water treatment method.

  6. The Modification of Sodium Polyacrylate Water Solution Cooling Properties by AL2O3

    Wojciech Gęstwa; Małgorzata Przyłęcka

    2010-01-01

    This paper presents a preliminary examination of water cooling ability as a result of its modification by the addition of sodium polyacrylate and AL2O3 nanoparticles. (AL2O3) alumina oxide was present in gamma phase as a form of nanopowder whose particle size was less than 50 nm. Cooling curves in the temperature-time system were marked for the three cooling media: water, 10% water solution of sodium polyacrylate, and 10% water solution of sodium polyacrylate with 1% addition of AL2O3 nanopar...

  7. IMPROVEMENT IN CONVENTIONAL WATER JACKET METHOD IN MOULD COOLING USING HEAT PIPE

    R.S.SHELKE

    2012-04-01

    Full Text Available Die casting moulds and injection moulding are cooled by conventional water jacket method. Cooling of mould is very essential for the purpose of quality of parts and cycle time. The conventional water jackets methods used are having many disadvantages, due to which the effect of mould cooling is not optimum. Hence a technique which can overcome all the disadvantages and become optimum emerged. The main aim of this proposed work is to improve conventional water jackets methods in mould cooling by the application of heat pipe. Heat pipeplays an very important role in such situations, and shows effective results, there by improving the conventional water jacket method in mould cooling. It transfers heat many times faster than pure copper.

  8. Containment for Heavy-Water Gas-Cooled Reactors

    The safety principles applicable to heavy-water, gas-cooled reactors are outlined, with a view to establishing containment specifications adapted to the sites available in Switzerland for the construction of nuclear plants. These specifications are derived from dose rates considered acceptable, in the event of a serious reactor accident, for persons living near the plant, and are based on-meteorological and demographic conditions representative of the majority of the country's sites. The authors consider various designs for the containment shell, taking into account the conditions which would exist in the shell after the maximum credible accident. The following types of shell are studied: pre-stressed concrete; pre-stressed concrete with steel dome; pre-stressed concrete with inner, leakproof steel lining; steel with concrete side shield to protect against radiation; double shell. The degree of leak proofing of the shells studied is regarded as a feature of the particular design and not as a fixed constructional specification. The authors assess the leak proofing properties of each type of shell and establish building costs for each of them on the basis of precise plans, with the collaboration of various specialized firms. They estimate the effectiveness of the various shells from a safety standpoint, in relation to different emergency procedures, in particular release into the atmosphere through appropriate filters and decontamination of the air within the shell by recycling through batteries of filters. The paper contains a very detailed comparison of about 10 cases corresponding to various combinations of design and emergency procedure; the comparison was made using a computer programme specially established for the purpose. The results are compared with those for a reactor of the same type and power, but assembled together with the heat exchangers in a pre-stressed concrete shell. (author)

  9. Thermal design of lithium bromide-water solution vapor absorption cooling system for indirect evaporative cooling for IT pod

    Sawant, Digvijay Ramkrishna

    Nowadays with increase use of internet, mobile there is increase in heat which ultimately increases the efficient cooling system of server room or IT POD. Use of traditional ways of cooling system has ultimately increased CO2 emission and depletion of CFC's are serious environmental issues which led scientific people to improve cooling techniques and eliminate use of CFC's. To reduce dependency on fossil fuels and 4environmental friendly system needed to be design. For being utilizing low grade energy source such as solar collector and reducing dependency on fossil fuel vapour absorption cooling system has shown a great driving force in today's refrigeration systems. This LiBr-water aabsorption cooling consists of five heat exchanger namely: Evaporator, Absorber, Solution Heat Exchanger, Generator, Condenser. The thermal design was done for a load of 23 kW and the procedure was described in the thesis. There are 120 servers in the IT POD emitting 196 W of heat each on full load and some of the heat was generated by the computer placed inside the IT POD. A detailed procedure has been discussed. A excel spreadsheet was to prepared with varying tube sizes to see the effect on flows and ultimately overall heat transfer coefficient.

  10. White Tower, London, England

    William the Conqueror; William Rufus; Henry I

    2007-01-01

    White Tower (Tower of London), London, England. Photograph taken by Terry Barry. There is restoration work being carried out on one of the towers. The White Tower is a central tower at the Tower of London. The great central keep was built by William the Conqueror and finished by his sons and successors, William Rufus and Henry I, around 1087. It is 90 feet high and is of massive construction, the walls varying from 15 feet thickness at the base to almost 11 feet in the upper parts. Above ...

  11. Accident analysis of heavy water cooled thorium breeder reactor

    Yulianti, Yanti [Department of Physics, University of Lampung Jl. Sumantri Brojonegoro No.1 Bandar Lampung, Indonesia Email: y-yanti@unila.ac.id (Indonesia); Su’ud, Zaki [Department of Physics, Bandung Institute of Technology Jl. Ganesha 10 Bandung, Indonesia Email: szaki@fi.itb.ac.id (Indonesia); Takaki, Naoyuki [Department of Nuclear Safety Engineering Cooperative Major in Nuclear Energy (Graduate School) 1-28-1 Tamazutsumi,Setagayaku, Tokyo158-8557, Japan Email: ntakaki@tcu.ac.jp (Japan)

    2015-04-16

    Thorium has lately attracted considerable attention because it is accumulating as a by-product of large scale rare earth mining. The objective of research is to analyze transient behavior of a heavy water cooled thorium breeder that is designed by Tokai University and Tokyo Institute of Technology. That is oxide fueled, PWR type reactor with heavy water as primary coolant. An example of the optimized core has relatively small moderator to fuel volume ratio (MFR) of 0.6 and the characteristics of the core are burn-up of 67 GWd/t, breeding ratio of 1.08, burn-up reactivity loss during cycles of < 0.2% dk/k, and negative coolant reactivity coefficient. One of the nuclear reactor accidents types examined here is Unprotected Transient over Power (UTOP) due to withdrawing of the control rod that result in the positive reactivity insertion so that the reactor power will increase rapidly. Another accident type is Unprotected Loss of Flow (ULOF) that caused by failure of coolant pumps. To analyze the reactor accidents, neutron distribution calculation in the nuclear reactor is the most important factor. The best expression for the neutron distribution is the Boltzmann transport equation. However, solving this equation is very difficult so that the space-time diffusion equation is commonly used. Usually, space-time diffusion equation is solved by employing a point kinetics approach. However, this approach is less accurate for a spatially heterogeneous nuclear reactor and the nuclear reactor with quite large reactivity input. Direct method is therefore used to solve space-time diffusion equation which consider spatial factor in detail during nuclear reactor accident simulation. Set of equations that obtained from full implicit finite-difference method is solved by using iterative methods. The indication of UTOP accident is decreasing macroscopic absorption cross-section that results large external reactivity, and ULOF accident is indicated by decreasing coolant flow. The

  12. Accident analysis of heavy water cooled thorium breeder reactor

    Thorium has lately attracted considerable attention because it is accumulating as a by-product of large scale rare earth mining. The objective of research is to analyze transient behavior of a heavy water cooled thorium breeder that is designed by Tokai University and Tokyo Institute of Technology. That is oxide fueled, PWR type reactor with heavy water as primary coolant. An example of the optimized core has relatively small moderator to fuel volume ratio (MFR) of 0.6 and the characteristics of the core are burn-up of 67 GWd/t, breeding ratio of 1.08, burn-up reactivity loss during cycles of < 0.2% dk/k, and negative coolant reactivity coefficient. One of the nuclear reactor accidents types examined here is Unprotected Transient over Power (UTOP) due to withdrawing of the control rod that result in the positive reactivity insertion so that the reactor power will increase rapidly. Another accident type is Unprotected Loss of Flow (ULOF) that caused by failure of coolant pumps. To analyze the reactor accidents, neutron distribution calculation in the nuclear reactor is the most important factor. The best expression for the neutron distribution is the Boltzmann transport equation. However, solving this equation is very difficult so that the space-time diffusion equation is commonly used. Usually, space-time diffusion equation is solved by employing a point kinetics approach. However, this approach is less accurate for a spatially heterogeneous nuclear reactor and the nuclear reactor with quite large reactivity input. Direct method is therefore used to solve space-time diffusion equation which consider spatial factor in detail during nuclear reactor accident simulation. Set of equations that obtained from full implicit finite-difference method is solved by using iterative methods. The indication of UTOP accident is decreasing macroscopic absorption cross-section that results large external reactivity, and ULOF accident is indicated by decreasing coolant flow. The

  13. Accident analysis of heavy water cooled thorium breeder reactor

    Yulianti, Yanti; Su'ud, Zaki; Takaki, Naoyuki

    2015-04-01

    Thorium has lately attracted considerable attention because it is accumulating as a by-product of large scale rare earth mining. The objective of research is to analyze transient behavior of a heavy water cooled thorium breeder that is designed by Tokai University and Tokyo Institute of Technology. That is oxide fueled, PWR type reactor with heavy water as primary coolant. An example of the optimized core has relatively small moderator to fuel volume ratio (MFR) of 0.6 and the characteristics of the core are burn-up of 67 GWd/t, breeding ratio of 1.08, burn-up reactivity loss during cycles of coolant reactivity coefficient. One of the nuclear reactor accidents types examined here is Unprotected Transient over Power (UTOP) due to withdrawing of the control rod that result in the positive reactivity insertion so that the reactor power will increase rapidly. Another accident type is Unprotected Loss of Flow (ULOF) that caused by failure of coolant pumps. To analyze the reactor accidents, neutron distribution calculation in the nuclear reactor is the most important factor. The best expression for the neutron distribution is the Boltzmann transport equation. However, solving this equation is very difficult so that the space-time diffusion equation is commonly used. Usually, space-time diffusion equation is solved by employing a point kinetics approach. However, this approach is less accurate for a spatially heterogeneous nuclear reactor and the nuclear reactor with quite large reactivity input. Direct method is therefore used to solve space-time diffusion equation which consider spatial factor in detail during nuclear reactor accident simulation. Set of equations that obtained from full implicit finite-difference method is solved by using iterative methods. The indication of UTOP accident is decreasing macroscopic absorption cross-section that results large external reactivity, and ULOF accident is indicated by decreasing coolant flow. The power reactor has a peak value

  14. Water source heat pumps for greenhouse soil cooling. Final report

    Spieser, H.

    1987-06-01

    In an attempt to diversify and grow flowers which are in high demand, growers are looking to produce certain exotic flowers which require unique growing conditions. One example is the Alstroemerias also knwon as the Peruvian Lily. If the plants are grown continuously at about 12-15/sup 0/C soil temperature, the plant will continue to flower regardless of air temperature and photoriod. These latter two factors are considered secondary to the importance of cool soil temperatures. Alstroemeria production is still relatively new to the greenhouse industry. Some controversy still exists as to the direct benefits of planned soil cooling. This project was set up to evaluate a mechanical soil cooling system for continuous year round Alstroemeria production. A heat pump soil cooling system was installed in two greenhouses each with dimensions of 16 m by 61 m. Combined these greenhouses have a growing area of 1952 m/sup 2/. These greenhouses are older wooden greenhouses, covered by double poly, air-inflated glazing. This system worked very well, maintaining the soil temperature at the proper levels throughout the spring and summer months. During the rest of the year the soil cooling system is used less intensely. During winter months when soil cooling is not required, the heat pumps provide base load heating to the greenhouse through fan forced unit heaters.

  15. Foulant Characteristics Comparison in Recycling Cooling Water System Makeup by Municipal Reclaimed Water and Surface Water in Power Plant

    Ping, Xu; Jing, Wang; Yajun, Zhang; Jie, Wang; Shuai, Si

    2015-01-01

    Due to water shortage, municipal reclaimed water rather than surface water was replenished into recycling cooling water system in power plants in some cities in China. In order to understand the effects of the measure on carbon steel corrosion, characteristics of two kinds of foulant produced in different systems were studied in the paper. Differences between municipal reclaimed water and surface water were analyzed firstly. Then, the weight and the morphology of two kinds of foulant were compared. Moreover, other characteristics including the total number of bacteria, sulfate reducing bacteria, iron bacteria, extracellular polymeric substance (EPS), protein (PN), and polysaccharide (PS) in foulant were analyzed. Based on results, it could be concluded that microbial and corrosive risk would be increased when the system replenished by municipal reclaimed water instead of surface water. PMID:25893132

  16. Conceptual design of a passive moderator cooling system for a pressure tube type natural circulation boiling water cooled reactor

    Kumar, Mukesh [Reactor Engineering Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Pal, Eshita, E-mail: eshi.pal@gmail.com [Homi Bhabha National Institute, Anushaktinagar, Mumbai 400 094 (India); Nayak, Arun K.; Vijayan, Pallipattu K. [Reactor Engineering Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India)

    2015-09-15

    Highlights: • Passive moderator cooling system is designed to cool moderator passively during SBO. • PMCS is a system of two natural circulation loops, coupled via a heat exchanger. • RELAP5 analyses show that PMCS maintains moderator within safe limits for 7 days. - Abstract: The recent Fukushima accident has raised strong concern and apprehensions about the safety of reactors in case of a prolonged Station Black Out (SBO) continuing for several days. In view of this, a detailed study was performed simulating this condition in Advanced Heavy Water Reactor. In this study, a novel concept of moderator cooling by passive means has been introduced in the reactor design. The Passive Moderator Cooling System (PMCS) consists of a shell and tube heat exchanger designed to remove 2 MW heat from the moderator inside Calandria. The heat exchanger is located at a suitable elevation from the Calandria of the reactor, such that the hot moderator rises due to buoyancy into the heat exchanger and upon cooling from shell side water returns to Calandria forming a natural circulation loop. The shell side of the heat exchanger is also a natural circulation loop connected to an overhead large water reservoir, namely the GDWP. The objective of the PMCS is to remove the heat from the moderator in case of an SBO and maintaining its temperature below the permissible safe limit (100 °C) for at least 7 days. The paper first describes the concept of the PMCS. The concept has been assessed considering a prolonged SBO for at least 7 days, through an integrated analysis performed using the code RELAP5/MOD3.2 considering all the major components of the reactor. The analysis shows that the PMCS is able to maintain the moderator temperature below boiling conditions for 7 days.

  17. Conceptual design of a passive moderator cooling system for a pressure tube type natural circulation boiling water cooled reactor

    Highlights: • Passive moderator cooling system is designed to cool moderator passively during SBO. • PMCS is a system of two natural circulation loops, coupled via a heat exchanger. • RELAP5 analyses show that PMCS maintains moderator within safe limits for 7 days. - Abstract: The recent Fukushima accident has raised strong concern and apprehensions about the safety of reactors in case of a prolonged Station Black Out (SBO) continuing for several days. In view of this, a detailed study was performed simulating this condition in Advanced Heavy Water Reactor. In this study, a novel concept of moderator cooling by passive means has been introduced in the reactor design. The Passive Moderator Cooling System (PMCS) consists of a shell and tube heat exchanger designed to remove 2 MW heat from the moderator inside Calandria. The heat exchanger is located at a suitable elevation from the Calandria of the reactor, such that the hot moderator rises due to buoyancy into the heat exchanger and upon cooling from shell side water returns to Calandria forming a natural circulation loop. The shell side of the heat exchanger is also a natural circulation loop connected to an overhead large water reservoir, namely the GDWP. The objective of the PMCS is to remove the heat from the moderator in case of an SBO and maintaining its temperature below the permissible safe limit (100 °C) for at least 7 days. The paper first describes the concept of the PMCS. The concept has been assessed considering a prolonged SBO for at least 7 days, through an integrated analysis performed using the code RELAP5/MOD3.2 considering all the major components of the reactor. The analysis shows that the PMCS is able to maintain the moderator temperature below boiling conditions for 7 days

  18. Acoustic Imaging Evaluation of Juvenile Salmonid Behavior in the Immediate Forebay of the Water Temperature Control Tower at Cougar Dam, 2010

    Khan, Fenton; Johnson, Gary E.; Royer, Ida M.; Phillips, Nathan RJ; Hughes, James S.; Fischer, Eric S.; Ploskey, Gene R.

    2011-10-01

    This report presents the results of an evaluation of juvenile Chinook salmonid (Oncorhynchus tshawytscha) behavior in the immediate forebay of the Water Temperature Control (WTC) tower at Cougar Dam in 2010. The study was conducted by the Pacific Northwest National Laboratory for the U.S. Army Corps of Engineers. The overall goal of the study was to characterize juvenile salmonid behavior and movement patterns in the immediate forebay of the WTC tower for fisheries resource managers to use to make decisions on bioengineering designs for long-term structures and/or operations to facilitate safe downstream passage for juvenile salmonids. We collected acoustic imaging (Dual-Frequency Identification Sonar; DIDSON) data from February 1, 2010 through January 31, 2011 to evaluate juvenile salmonid behavior year-round in the immediate forebay surface layer of the WTC tower (within 20 m, depth 0-5 m). From October 28, 2010 through January 31, 2011 a BlueView acoustic camera was also deployed in an attempt to determine its usefulness for future studies as well as augment the DIDSON data. For the DIDSON data, we processed a total of 35 separate 24-h periods systematically covering every other week in the 12-month study. Two different 24-hour periods were processed for the BlueView data for the feasibility study. Juvenile salmonids were present in the immediate forebay of the WTC tower throughout 2010. The juvenile salmonid abundance index was low in the spring (<200 fish per sample-day), began increasing in late April and peaked in mid-May. Fish abundance index began decreasing in early June and remained low in the summer months. Fish abundance increased again in the fall, starting in October, and peaked on November 8-9. A second peak occurred on December 22. Afterwards, abundance was low for the rest of the study (through January 2011). Average fish length for juvenile salmonids during early spring 2010 was 214 {+-} 86 mm (standard deviation). From May through early November

  19. Development and characterization of aluminum stranded water cooled conductor for rapid cycling synchrotron magnets

    Magnet coils of rapid cycling synchrotron are subjected to time varying magnetic fields and a special water cooled stranded conductor is preferred for making magnet coils to reduce eddy current losses, magnetic field inhomogeneity and operating costs of magnets. A continuous length (∼ 50 m) aluminum stranded water cooled conductor is indigenously developed. Five stranded magnet coils are wound and epoxy resin impregnated as per the technical requirements. The stranded conductor magnet coils are assembled with a laminated dipole magnet core for their electrical characterization. The development of water cooled aluminum stranded conductor, characterization of stranded magnet coils will be discussed in this paper. (author)

  20. Performance Optimization of the Water Cooling System for Resonance Frequency Control of the PEFP DTL

    The objective of in this research project is prototype cooling water skid of separated closed loop in order to supply and withdraw low conductivity deionized water in drift tube of drift tube linac as core components of proton accelerates. This report is dealt with design specification of J-PARC 400 MeV Linac cooling water system, PEFP DTL cooling system, specification of RCCS21-24, RCCS101 with pump, loss coefficient for DTL2 modeling, pressure drop with flow rate of heat exchanger.

  1. Thermohydraulic relationships for advanced water cooled reactors and the role of the IAEA

    Under the auspices of the International Atomic Energy Agency (IAEA) a Coordinated Research Program (CRP) on Thermohydraulic Relationships for Advanced Water-Cooled Reactors was carried out from 1995-1998. It was included into the IAEA's Programme following endorsement in 1995 by the International Working Group on Advanced Technologies for Water Cooled Reactors. The overall goal was to promote International Information exchange and cooperation in establishing a consistent set of thermohydraulic relationships that are appropriate for use in analyzing the performance and safety of advanced water-cooled reactors. (authors)

  2. Thermohydraulic relationships for advanced water cooled reactors, and the role of IAEA

    Under the auspices of the International Atomic Energy Agency (IAEA) a Coordinated Research Program (CRP) on Thermohydraulic Relationships for Advanced Water-Cooled Reactors was carried out from 1995-1999. It was included into the IAEA's Programme following endorsement in 1995 by the IAEA's International Working Group on Advanced Technologies for Water Cooled Reactors. The overall goal was to promote international information exchange and cooperation in establishing a consistent set of thermohydraulic relationships that are appropriate for use in analyzing the performance and safety of advanced water cooled reactors. (authors)

  3. Design measures in evolutionary water cooled reactors to optimize for economic viability

    Since the mid 1980s, there have been various efforts to develop evolutionary water cooled reactors based on the current operating plant experience. To sustain and improve the economic viability, particular attention has been paid to the following aspects in developing evolutionary water cooled reactors: design simplification and increased operating margins, standardization in design as well as construction and operation, integration of operating plant insights, and consideration of safety, operability and constructability during the design stage. This paper reviews each item and discusses several examples from some of the evolutionary water cooled reactors being developed. (author)

  4. Key aspects of the safety study of a water-cooled fusion DEMO reactor

    Key aspects of the safety study of a water-cooled fusion DEMO reactor is reported. Safety requirements, dose target, DEMO plant model and confinement strategy of the safety study are briefly introduced. The internal hazard of a water-cooled DEMO, i.e. identification of hazardous inventories, identification of stored energies that can mobilize these hazardous inventories and identification of accident initiators and scenarios, are evaluated. It is pointed out that the enthalpy in the first wall/blanket cooling loops, the decay heat and the energy potentially released by the Be-steam chemical reaction are of special concern for the water-cooled DEMO. An ex-vessel loss-of-coolant accident (ex-VV LOCA) of the first wall/blanket cooling loop is also quantitatively analyzed. The integrity of the building against the ex-VV LOCA is discussed. (author)

  5. Batch Cooling Crystallization of Potassium Sulphate from Water Solution

    Kalšan, M.

    2009-12-01

    Full Text Available Batch cooling crystallization, at the rotation speed of 700 min–1, of an aqueous solution of a potassium sulphate has been investigated on a laboratory scale. The effect of hydrodynamics conditions on the crystallization process were investigated by using different type of impellers. Two types of impellers were investigated; the four-pitched blade impeller which generates axi-al flow and the six-blades Rusthon turbine which generates radial flow. The experiments were performed at four different linear cooling rates in the range from 8-20 °C h–1 for both types of impeller.The influence of the cooling rates on the metastable zone width, the crystallization kinetics and the granulometric properties of the obtained crystals were investigated. The experimental data show that higher cooling rate expands the metastable zone for all the types of impeller (Fig. 2 and influences the crystal size distribution (Fig. 7 and Fig. 8.At low cooling rates, supersaturation was kept at a constant value for a longer period. It resulted in improved conditions for mass transfer and the crystals grew. Bigger crystals were obtained at lower cooling rates (Fig. 7.It is stated that radial flow (Rusthon turbine is particularly inappropriate for the nucleation process, and for crystallization. Nucleation started at a lower temperature and higher supersaturation (Fig. 3. These conditions resulted in a high nucleation’s rate and large number of nucleation centres.Also, the obtained crystals settled on the wall of the reactor, baffles and stirrer. A great part of the obtained crystals was agglomerated. The nucleation order, n and coefficient of nucleation, kn were determined for different cooling rates (Fig. 5a. The nucleation order is higher at radial flow (nucleation started at higher supersaturation. The relation between the rate of concentration drop in a solution and supersaturation has beenapproximated with a power low equation (Fig. 5b. For the used impellers

  6. Comparison of solar panel cooling system by using dc brushless fan and dc water

    Irwan, Y. M.; Leow, W. Z.; Irwanto, M.; M, Fareq; Hassan, S. I. S.; Safwati, I.; Amelia, A. R.

    2015-06-01

    The purpose of this article is to discuss comparison of solar panel cooling system by using DC brushless fan and DC water pump. Solar photovoltaic (PV) power generation is an interesting technique to reduce non-renewable energy consumption and as a renewable energy. The temperature of PV modules increases when it absorbs solar radiation, causing a decrease in efficiency. A solar cooling system is design, construct and experimentally researched within this work. To make an effort to cool the PV module, Direct Current (DC) brushless fan and DC water pump with inlet/outlet manifold are designed for constant air movement and water flow circulation at the back side and front side of PV module representatively. Temperature sensors were installed on the PV module to detect temperature of PV. PIC microcontroller was used to control the DC brushless fan and water pump for switch ON or OFF depend on the temperature of PV module automatically. The performance with and without cooling system are shown in this experiment. The PV module with DC water pump cooling system increase 3.52%, 36.27%, 38.98%in term of output voltage, output current, output power respectively. It decrease 6.36 °C compare than to PV module without DC water pump cooling system. While DC brushless fan cooling system increase 3.47%, 29.55%, 32.23%in term of output voltage, output current, and output power respectively. It decrease 6.1 °C compare than to PV module without DC brushless fan cooling system. The efficiency of PV module with cooling system was increasing compared to PV module without cooling system; this is because the ambient temperature dropped significantly. The higher efficiency of PV cell, the payback period of the system can be shorted and the lifespan of PV module can also be longer.

  7. Biofouling in cooling water system of nuclear power plant and its safety consequences: a perspective

    Full text: Nuclear power plants require large quantities of water to cool system components and extract heat from the steam. This water is supplied from rivers, lakes, oceans and estuaries that support a large number of biological organisms, many of which cannot be removed from the water before it is used. These aquatic organisms can cause serious problems in nuclear power plant cooling water systems. Over the past several years, many cooling water systems at nuclear power plants have become infested with fouling organisms. These organisms have clogged cooling water flow, endangering the safety-related systems at some power plants. Therefore, the potential exists for biofouling to adversely affect the operability of plant components and cooling water systems during normal operation, shutdown, or accident conditions. This paper discusses reported cases of biofouling in cooling water system affecting directly or indirectly the safety components in nuclear power plants. It also describes the current status of control and surveillance strategies in use at nuclear power plants. Projected improvements and alternatives strategies are also touched upon

  8. Water mist effect on cooling range and efficiency of casting die

    R. Władysiak

    2008-12-01

    Full Text Available This project is showing investigation results of cooling process of casting die in the temperature range 570÷100 °C with 0.40 MPa compressed air and water mist streamed under pressure 0.25÷0.45 MPa in air jet 0.25÷0.50 MPa using open cooling system.The character and the speed of changes of temperature, forming of the temperture’s gradient along parallel layer to cooled surface of die is shawing with thermal and derivative curves. The effect of kind of cooling factor on the temperature and time and distance from cooling nozzle is presented in the paper. A designed device for generating the water mist cooling the die and the view of sprying water stream is shown here. It’s proved that using of the water mist together with the change of heat transfer interface increases intensity of cooling in the zone and makes less the range cooling zone and reduces the porosity of cast microstructure.

  9. Sustained Recycle in Light Water and Sodium-Cooled Reactors

    Steven J. Piet; Samuel E. Bays; Michael A. Pope; Gilles J. Youinou

    2010-11-01

    From a physics standpoint, it is feasible to sustain recycle of used fuel in either thermal or fast reactors. This paper examines multi-recycle potential performance by considering three recycling approaches and calculating several fuel cycle parameters, including heat, gamma, and neutron emission of fresh fuel; radiotoxicity of waste; and uranium utilization. The first recycle approach is homogeneous mixed oxide (MOX) fuel assemblies in a light water reactor (LWR). The transuranic portion of the MOX was varied among Pu, NpPu, NpPuAm, or all-TRU. (All-TRU means all isotopes through Cf-252.) The Pu case was allowed to go to 10% Pu in fresh fuel, but when the minor actinides were included, the transuranic enrichment was kept below 8% to satisfy the expected void reactivity constraint. The uranium portion of the MOX was enriched uranium. That enrichment was increased (to as much as 6.5%) to keep the fuel critical for a typical LWR irradiation. The second approach uses heterogeneous inert matrix fuel (IMF) assemblies in an LWR - a mix of IMF and traditional UOX pins. The uranium-free IMF fuel pins were Pu, NpPu, NpPuAm, or all-TRU. The UOX pins were limited to 4.95% U-235 enrichment. The number of IMF pins was set so that the amount of TRU in discharged fuel from recycle N (from both IMF and UOX pins) was made into the new IMF pins for recycle N+1. Up to 60 of the 264 pins in a fuel assembly were IMF. The assembly-average TRU content was 1-6%. The third approach uses fast reactor oxide fuel in a sodium-cooled fast reactor with transuranic conversion ratio of 0.50 and 1.00. The transuranic conversion ratio is the production of transuranics divided by destruction of transuranics. The FR at CR=0.50 is similar to the CR for the MOX case. The fast reactor cases had a transuranic content of 33-38%, higher than IMF or MOX.

  10. Possible efficiency improvement by application of various operating regimes for the cooling water pump station at thermal power plant - Bitola

    Mijakovski Vladimir; Mitrevski Vangelče; Mijakovski Nikola

    2012-01-01

    Thermal power plant (TPP) - Bitola is the largest electricity producer in the Republic of Macedonia with installed capacity of 691 MW. It is a lignite fired power plant, in operation since 1982. Most of the installed equipment is of Russian origin. Power plant's cold end comprised of a condenser, pump station and cooling tower is depicted in the article. Possible way to raise the efficiency of the cold end by changing the operating characteristics of the pumps is presented in the articl...

  11. Wetland Water Cooling Partnership: The Use of Constructed Wetlands to Enhance Thermoelectric Power Plant Cooling and Mitigate the Demand of Surface Water Use

    Apfelbaum, Steven; Duvall, Kenneth; Nelson, Theresa; Mensing, Douglas; Bengtson, Harlan; Eppich, John; Penhallegon, Clayton; Thompson, Ry

    2013-09-30

    Through the Phase I study segment of contract #DE-NT0006644 with the U.S. Department of Energy’s National Energy Technology Laboratory, Applied Ecological Services, Inc. and Sterling Energy Services, LLC (the AES/SES Team) explored the use of constructed wetlands to help address stresses on surface water and groundwater resources from thermoelectric power plant cooling and makeup water requirements. The project objectives were crafted to explore and develop implementable water conservation and cooling strategies using constructed wetlands (not existing, naturally occurring wetlands), with the goal of determining if this strategy has the potential to reduce surface water and groundwater withdrawals of thermoelectric power plants throughout the country. Our team’s exploratory work has documented what appears to be a significant and practical potential for augmenting power plant cooling water resources for makeup supply at many, but not all, thermoelectric power plant sites. The intent is to help alleviate stress on existing surface water and groundwater resources through harvesting, storing, polishing and beneficially re-using critical water resources. Through literature review, development of conceptual created wetland plans, and STELLA-based modeling, the AES/SES team has developed heat and water balances for conventional thermoelectric power plants to evaluate wetland size requirements, water use, and comparative cooling technology costs. The ecological literature on organism tolerances to heated waters was used to understand the range of ecological outcomes achievable in created wetlands. This study suggests that wetlands and water harvesting can provide a practical and cost-effective strategy to augment cooling waters for thermoelectric power plants in many geographic settings of the United States, particularly east of the 100th meridian, and in coastal and riverine locations. The study concluded that constructed wetlands can have significant positive

  12. Custom design of a hanging cooling water power generating system applied to a sensitive cooling water discharge weir in a seaside power plant: A challenging energy scheme

    In this study, an innovative design of hydro-electricity system was applied to an unconventional site in an attempt to generate electricity from the exhaust cooling water of a coal-fired power plant. Inspired by the idea of micro hydro, present study can be considered new in three aspects: design, resource and site. This system was hung at a cooling water discharge weir, where all sorts of civil work were prohibited and sea water was used as the cooling water. It was designed and fabricated in the university's mechanical workshop and transported to the site for installation. The system was then put into proof run for a three-month period and achieved some success. Due to safety reasons, on-site testing was prohibited by the power plant authority. Hence, most data was acquired from the proof run. The driving system efficiency was tested in the range of 25% and 45% experimentally while modeling results came close to experimental results. Payback period for the system is estimated to be about 4.23 years. Result obtained validates the feasibility of the overall design under the sensitive site application. - Highlights: • Challenging energy scheme via a hanging cooling water power generating system. • Driving system efficiency was tested in the range of 25% and 45%. • Payback period for the system is estimated to be about 4.2 years

  13. Fluid Induced Vibration Analysis of a Cooling Water Pipeline for the HANARO CNS

    CNS is the initial of Cold Neutron Source and the CNS facility system consists of hydrogen, a vacuum, a gas blanketing, a helium refrigeration and a cooling water supply system. Out of these subsystems, the helium refrigeration system has the function of removal of heat from a thermal neutron under reactor operation. Therefore, HRS (helium refrigeration system) must be under normal operation for the production of cold neutron. HRS is mainly made up of a helium compressor and a coldbox. This equipment is in need of cooling water to get rid of heat generation under stable operation and a cooling water system is essential to maintain the normal operation of a helium compressor and a coldbox. The main problem for the cooling water system is the vibration issue in the middle of operation due to a water flow in a pipeline. In order to suppress the vibration problem for a pipeline, the characteristics of a pipeline and fluid flow must be analyzed in detail. In this paper, fluid induced vibration of a cooling water pipe is analyzed numerically and the stability of the cooling water pipeline is investigated by using pipe dynamic theory

  14. Applicability of a desiccant dew-point cooling system independent of external water sources

    Bellemo, Lorenzo; Elmegaard, Brian; Kærn, Martin;

    2015-01-01

    The applicability of a technical solution for making desiccant cooling systems independent of external water sources is investigated. Water is produced by condensing the desorbed water vapour in a closed regeneration circuit. Desorbed water recovery is applied to a desiccant dew-point cooling...... system, which includes a desiccant wheel and a dew point cooler. The system is simulated during the summer period in the Mediterranean climate of Rome and it results completely independent of external water sources. The seasonal thermal COP drops 8% in comparison to the open regeneration circuit solution...

  15. Development of Non-water cooling Induction coil of Ingot Casting Equipment for Uranium Deposits

    Lee, Yoon Sang; Cho, Choon Ho; Lee, Sung Ho; Lee, Han Soo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2009-10-15

    The ingot casting equipment for uranium deposits is to make an ingot with uranium deposits produced from an electro-refiner by a pyro-processing method. The ingot casting equipment consists of crucible, feeder and mold. The crucible is heated by induction coil. Usually in industry they use a water-cooling induction coil for there is a lot of heat generation through the heating coil. We introduce a new idea to improve safety with non-water cooling coil in ingot casting equipment for uranium deposits, because in the hot-cell operation, if there were leakage from water-cooling induction coil, there could be a troublesome accident. In this paper, we introduce the experimental results of non-water cooling induction coil.

  16. Development of Non-water cooling Induction coil of Ingot Casting Equipment for Uranium Deposits

    The ingot casting equipment for uranium deposits is to make an ingot with uranium deposits produced from an electro-refiner by a pyro-processing method. The ingot casting equipment consists of crucible, feeder and mold. The crucible is heated by induction coil. Usually in industry they use a water-cooling induction coil for there is a lot of heat generation through the heating coil. We introduce a new idea to improve safety with non-water cooling coil in ingot casting equipment for uranium deposits, because in the hot-cell operation, if there were leakage from water-cooling induction coil, there could be a troublesome accident. In this paper, we introduce the experimental results of non-water cooling induction coil

  17. Performance test of filtering system for controlling the turbidity of secondary cooling water in HANARO

    There is about 80 m3/h loss of the secondary cooling water by evaporation, windage and blowdown during the operation of HANARO, 30 MW research reactor. When the secondary cooling water is treated by high Ca-hardness treatment program for minimizing the blowdown loss, only the trubidity exceeds the limit. By adding filtering system it was confirned, through the relation of turbidity and filtering rate of secondary cooling water, that the turbidity is reduced below the limit (5 deg.) by 2 % of filtering rate without blowdown. And it was verified, through the field performace test of filtering system under normal operation condition, that the circulation pumps get proper capacity and that filter units reduce the turbidity below the limit. Therefore, the secondary cooling water can be treated by the high Ca-hardness program and filter system without blowdown

  18. Comparative Assessment of an Innovative Dry-Cooled CSP System

    Poullikkas, Andreas; Hadjipaschalis, Ioannis; Kourtis, George

    2013-01-01

    A comparative optimization assessment is carried out in order to identify the competitiveness of an innovative modular air-cooled condenser (MACC) system in relation to conventional water- or air-cooled condensers. Specifically, the technoeconomic performance of the combined cycle gas turbine (CCGT) technology, the parabolic trough concentrated solar power (CSP) technology, and the solar tower CSP technology are compared when all are integrated (a) with a MACC condenser of an optimum tube geo...

  19. Study of water radiolysis in relation with the primary cooling circuit of pressurized water reactors

    This memorandum shows a fundamental study on the water radiolysis in relation with the cooling primary circuit of PWR type reactors. The water of the primary circuit contains boric acid a soluble neutronic poison and also hydrogen that has for role to inhibit the water decomposition under radiation effect. In the aim to better understand the mechanism of dissolved hydrogen action and to evaluate the impact of several parameters on this mechanism, aqueous solutions with boric acid and hydrogen have been irradiated in a experimental nuclear reactor, at 30, 100 and 200 Celsius degrees. It has been found that, with hydrogen, the water decomposition under irradiation is a threshold phenomenon in function of the ratio between the radiation flux '1' B(n, )'7 Li and the gamma flux. When this ratio become too high, the number of radicals is not sufficient to participate at the chain reaction, and then water is decomposed in O2 and H2O2 in a irreversible way. The temperature has a beneficial part on this mechanism. The iron ion and the copper ion favour the water decomposition. (N.C.)

  20. Achieving reduced fouling of cooling water exchangers with stainless steel tubes

    Good performance of cooling water heat exchangers plays a vital role in the over all energy efficiency of a chemical plant. Heavy fouling on carbon steel tubes of the cooling water exchangers was causing poor performance and frequent cleaning requirement. The carbon steel tubes were replaced with stainless steel tubes. Improved performance was achieved and cleaning frequency reduced. The paper covers the details of study and methodology applied for the above changes along with summary of results. (author)

  1. Light water cooled, high temperature and high performance nuclear power plants concept of once-through coolant cycle, supercritical-pressure, light water cooled nuclear reactors

    Supercritical-pressure, light water cooled nuclear reactors corresponding to nuclear reactors of once-through boilers, are of theoretical development from LWR. Under supercritical pressure, a steam turbine can be driven directly with cooled water with high enthalpy, as not seen boiling and required for recycling. The reactor has no steam-water separation and recycling systems on comparison with the boiling water type LWR, and is the same once-through type as supercritical-pressure thermal power generation plants. Then, all of cooling water at reactor core are sent to turbine. The reactor has no steam generator, and pressurizer, on comparison with PWR. As it requires no steam-water separator, steam drier, and recycling system on comparison with BWR, it becomes of smaller size and has shape and size nearly equal to those of PWR. And, its control bars can be inserted from upper direction like PWR, and can use its driving system. Here was introduced some concepts on high-temperature and high-performance light water reactor, nuclear power generation using a technology on supercritical-pressure thermal power generation. (G.K.)

  2. The Leaning Tower

    石夫

    2005-01-01

    W hy does the Leaning Tower of Pisa in Italy lean?It leans because of a m istake.It has leanedalm ostsince the day the tower was built.In1173,the people ofPisa,Italy,wanted to build a belltower.They wanted the tower to be them ost beautiful bell tower in all of Italy.The city also needed a bell tower because the church did nothave one.H owever,there was a problem.As soon as the firstfloor ofthe building was finished,the towerstarted to lean.Builders tried to m ake the building straight again as they added m...

  3. Closed-cycle process of coke-cooling water in delayed coking unit

    Synthesized processes are commonly used to treat coke-cooling wastewater. These include cold coke-cut water, diluting coke-cooling water, adding chemical deodorization into oily water, high-speed centrifugal separation, de-oiling and deodorization by coke adsorption, and open nature cooling. However, because of water and volatile evaporation loss, it is not suitable to process high-sulphur heavy oil using open treatments. This paper proposed a closed-cycling process in order to solve the wastewater treatment problem. The process is based on the characteristics of coke-cooling water, such as rapid parametric variation, oil-water-coke emulsification and steam-water mixing. The paper discussed the material characteristics and general idea of the study. The process of closed-cycle separation and utilization process of coke-cooling water was presented along with a process flow diagram. Several applications were presented, including a picture of hydrocyclones for pollution separation and a picture of equipments of pollution separation and components regeneration. The results showed good effect had been achieved since the coke-cooling water system was put into production in 2004. The recycling ratios for the components of the coke-cooling water were 100 per cent, and air quality in the operating area reached the requirements of the national operating site circumstance and the health standards. Calibration results of the demonstration unit were presented. It was concluded that since the devices went into operation, the function of production has been normal and stable. The operation was simple, flexible, adjustable and reliable, with significant economic efficiency and environmental benefits. 10 refs., 2 tabs., 3 figs

  4. Vaporization Rate Analysis of Primary Cooling Water from Reactor PUSPATI TRIGA (RTP) Tank

    Primary cooling system consists of pumps, heat exchangers, probes, a nitrogen-16 diffuser and associated valves is connected to the reactor TRIGA PUSPATI (RTP) tank by aluminium pipes. Both the primary cooling system and the reactor tank is filled with demineralized light water (H2O), which serves as a coolant, moderator as well as shielding. During reactor operation, vaporization in the reactor tank will reduce the primary water and contribute to the formation of vapor in the reactor hall. The vaporization may influence the function of the water subsequently may affect the safety of the reactor operation. It is essential to know the vaporization rate of the primary water to ensure its functionality. This paper will present the vaporization rate of the primary cooling water from the reactor tank and the influence of temperature of the water in the reactor tank to the vaporization rate. (author)

  5. Kinetic model for predicting the concentrations of active halogen species in chlorinated saline cooling waters

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

    1979-01-01

    A kinetic model for predicting the composition of chlorinated water discharged from power plants using fresh water for cooling was previously reported. The model has now been extended to be applicable to power plants located on estuaries or on the seacoast where saline water is used for cooling purposes. When chloride is added to seawater to prevent biofouling in cooling systems, bromine is liberated. Since this reaction proceeds at a finite rate there is a competition between the bromine (i.e., hypobromous acid) and the added chlorine (i.e., hypochlorous acid) for halogenation of any amine species present in the water. Hence not only chloramines but also bromamines and bromochloramines will be formed, with the relative concentrations a function of the pH, temperature, and salinity of the water. The kinetic model takes into account the chemical reactions leading to the formation and disappearance of the more important halamines and hypohalous acids likely to be encountered in chlorinated saline water.

  6. Heat transfer enhancement using air-atomized spray cooling with water-Al2O3 nano-fluid

    The study deals with the air-atomized spray cooling using nano-fluid as the cooling media for high heat flux applications. The nano-fluid has been prepared by commercial Al2O3 particles of diameter less than 13 nm and water. Heat transfer study has been carried out on a pre-heated steel specimen of dimensions 100 mm x 100 mm x 6 mm. The initial temperature of the plate which was subjected to air-atomized spray cooling was over 900 deg. C. Various coolants consisting of 0.1% volumetric concentration of water -Al2O3 mixture, with or without a dispersing agent (surfactant) were used for the study. The dispersing agents used are sodium dodecyl sulphate (SDS) and polyoxyethylene (20) sorbitan monolaurate (Tween 20). Inverse heat conduction software INTEMP has been used for estimating the surface heat flux and temperatures taking into account the measured internal temperature histories by the thermocouples during the cooling process. The results obtained using nano-fluid coolants are compared with that of the results where pure water (filtered potable water) is used as a coolant. The analyses reveal that the cooling rate, critical heat flux and heat transfer coefficients are significantly enhanced when nano-fluids are used as coolants in air-atomized spray process. Also, the nano-fluid coolants with dispersing agent shows a better enhancement of heat transfer over that of the nano-fluid without the dispersing media. The nano-fluid with dispersing agent Tween 20 is found more effective than that of its counterpart. Overall, the percentage enhancement in cooling rate of all these nano-fluids compared with pure water (filtered potable water) is 10.2% for water-Al2O3, 18.6% for water-Al2O3-SDS, and up to 32.3% for water-Al2O3 -Tween 20. (authors)

  7. Critical review of water based radiant cooling system design methods

    Feng, Jingjuan Dove; Bauman, Fred; Schiavon, Stefano

    2014-01-01

    Interests in radiant cooling systems have increased in recent years. There is, however, no standardized method for radiant system design that is broadly accepted by the building industry. Through literature review, twelve surveys and eight interviews with leading practitioners, this paper summarizes the design methods documented in the guidelines, assesses the state of the industry, and identifies potential gaps and limitations in current design practice. The findings include: 1) design guide...

  8. 某电厂1#冷却塔不均匀沉降成因分析及处理方案研究%Analysis and Treatment Scheme for Differential Settlement of the 1# Cooling Tower in a Power Plant

    赵来顺; 雷珂娜

    2013-01-01

    分析了某电厂1#冷却塔产生不均匀沉降的原因,主要是由于地基土浸水发生了湿陷性沉降.根据冷却塔结构特征和工程问题特点提出了钻孔灌注桩基础托换法加固处理方案.钻孔灌注桩基础托换法即将原来基础上承受的全部或部分荷载通过新增灌注桩传递到深部较好且无湿陷性的土层上,加固了既有地基基础并阻止上部建筑继续沉降.另外,介绍了加固用钻孔灌注桩的选型、定位、单桩承载力确定方法及桩承台与原基础结合面连接方法,并对加固处理效果进行了预测.%In this paper,the differential settlement causes of the 1# cooling tower in a power plant was analyzed.It is indicated that the settlement is primarily due to collapsible settlement of the foundation soil with water immersion.The cast-in-place pile foundation was proposed for cooling tower strengthening.Therefore,the entire or partial exiting loads can be passed to deeper soil layer.In this way,foundation can be reinforced and settlement can be controlled.Design features of reinforced concrete piles including lectotype and location,the method to determine single pile bearing capacity,and details of bar connection between pile caps and the original foundation joint surface were introduced and the reinforcement effects were predicted.It can be referred by similar engineering projets.

  9. Effect of Fouling Mitigation for Ceramic Ball in Cooling Water System of Heat Exchanger

    The objective of this study was to investigate the effects of fouling mitigation for ceramic ball in cooling water system experimentally. The devices filled with ceramic balls were connected to the bypass line of the heat exchanging system. Cooling water in the heat exchanging system was artificial water. To visualize the formation of fouling on the heat transfer surface a number of images were obtained using a CCD camera with real-time microscopy. Fouling resistances and overall heat transfer coefficients were measured in order to analyze fouling mitigation effects. We found that the ceramic ball devices for artificial water reduced the formation of fouling compared to the no-mitigation devices

  10. Microbial speciation and biofouling potential of cooling water used by Ontario Hydro

    The cooling water composition and microbial components of biofilms attached to stainless steel wafers submerged in three lake water types were evaluated to determine whether their biofouling potential differed in a predictable manner. The composition of the lake waters was different which affected biofilm composition, where the predominance of specific microbial groups varied between test systems and with time. Some prediction of biofouling potential was possible, and it was concluded that the cooling water in the vicinity of Bruce NGS had the lowest biofouling potential whereas greater biofouling could be expected in the Pickering and Nanticoke stations

  11. Methods for combating microorganisms in cooling water systems - a literature study and a market inventory

    One of the greatest current problems in both closed and open cooling water systems is that of micro- and macro-organisms. In view of the environmental effects associated with the discharge of chemicals, the range of biocides and alternative methods for combating micro-organisms has increased during recent years. This report presents a brief description of the organisms which contribute to corrosion problems and the mechanisms associated with microbial corrosion. Thereafter descriptions are given of 15 different biocides which are used in both open and closed cooling systems. In each case, details are given of their chemical compositions and mode of action and of their effects on metals and on the environment. Finally, alternative methods of combating micro-organisms in cooling water systems are briefly described. The report also includes a survey of the biocides for cooling water systems which are available on the Swedish market. (author)

  12. LiOH as corrosion inhibitor for component cooling water system in PWR

    The cooling water system for the auxiliary machines and coolers in the primary cooling system of a PWR forms closed loops, and has the function to prevent the release of fluid containing radioactive substances even if leak occurs in the primary cooling system. This system is mainly composed of carbon steel, and copper and its alloys are used for the sea water cooling. The auxiliary machines and coolers in the primary cooling system are made of stainless steel. Therefore, the rust prevention method used for this system must be effective for these metals or must not give harmful effect. As the rust prevention method for the plants in operation, chromic acid process and hydrazine process have been used, but the environmental pollution by chrome and the ammonia attack on copper alloys may occur. As the rust prevention process to improve these problems, LiOH method was examined. This cooling water system comprises four pumps, four water coolers, one surge tank, pipes and valves, and the water quality control in the system is explained. The rust prevention effect of LiOH for carbon steel, copper and its alloys was examined. Particular consideration is not required in the case of copper and its alloys, but pH higher than 12 is unsuitalbe. For the perfect rust prevention of carbon steel, the dissolved oxygen concentration must be less than 0.1 ppn, and pH must be more than 10. (Kako,I.)

  13. 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; Grohnde. Dokumentation der Polizeieinsaetze anlaesslich der Demonstration gegen das Kernkraftwerk Grohnde am 19.03.1977 und der Raeumung des besetzten Kuehlturmgelaendes am 23.08.1977

    Stricker, Michael

    2014-07-01

    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.

  14. The situation of the cooling water in the Federal Republic of Germany 1976

    Approximately 75% of the water demand in the Federal Republic of Germany are being used for cooling purposes. In spite of this important share, the topic of the discharge of waste heat was slumbering in nothingness until the end of the sixties. The principle according to which power plants were only designed for fresh water cooling had only been broken in a few areas (such as the Rhenish brown coal district or in the Ruhr pit coal area). After the Rhine had been included in the power plant design, the public interest changed lastingly. A problem which remains to be settled is that one of the limits to the extraction of water for cooling purposes. Often people fail to see that in addition to the other uses, the waters also fulfil the important function of supplying make-up water for cooling purposes. In some regions, this supply can only be secured by means of lare-area economics of water supply and distribution (artificial measures). All questions pertaining to the cooling water requirements and how they are to be met should soon be settled in fruitful discussions with the representatives of the Laender. (orig.)

  15. The situation of cooling water in the Federal Republic of Germany 1976

    Approximately 75% of the water demand in the Federal Republic of Germany are being used for cooling purposes. In spite of this important share, the topic of the discharge of waste heat was slumbering in nothingness until the end of the 'sixties. The principle according to which power plants were only designed for fresh water cooling had only been broken in a few areas (such as the Rhenish brown coal district or in the Ruhr pit coal area). After the Rhine had been included in the power plant design, the public interest changed lastingly. A problem which remains to be settled is that one of the limits ot the extraction of water for cooling purposes. Often people fail to see that in addition to the other uses, the waters also fulfil the important function of supplying make-up water for cooling purposes. In some regions, this supply can only be secured by means of large-area economics of water supply and distribution (artificial measures). All questions pertaining to the cooling water requirements and how they are to be met should soon be settled in fruitful discussions with the representatives of the Laender. (orig.)

  16. Water-lithium bromide double-effect absorption cooling analysis. Final report

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

    1980-12-01

    This investigation involved the development of a numerical model for the transient simulation of the double-effect, water-lithium bromide absorption cooling machine, and the use of the model 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 sensitivity analysis was performed by selecting a nominal condition and determining performance sensitivity for each variable with others held constant. The variables considered in the study 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 indicated in particular 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. The dynamic model should be valuable as a design tool for developing new absorption machines or modifying current machines to make them optimal based on current and future energy costs.

  17. Improving of the photovoltaic / thermal system performance using water cooling technique

    Hussien, Hashim A.; Numan, Ali H.; Abdulmunem, Abdulmunem R.

    2015-04-01

    This work is devoted to improving the electrical efficiency by reducing the rate of thermal energy of a photovoltaic/thermal system (PV/T).This is achieved by design cooling technique which consists of a heat exchanger and water circulating pipes placed at PV module rear surface to solve the problem of the high heat stored inside the PV cells during the operation. An experimental rig is designed to investigate and evaluate PV module performance with the proposed cooling technique. This cooling technique is the first work in Iraq to dissipate the heat from PV module. The experimental results indicated that due to the heat loss by convection between water and the PV panel's upper surface, an increase of output power is achieved. It was found that without active cooling, the temperature of the PV module was high and solar cells could only achieve a conversion efficiency of about 8%. However, when the PV module was operated under active water cooling condition, the temperature was dropped from 76.8°C without cooling to 70.1°C with active cooling. This temperature dropping led to increase in the electrical efficiency of solar panel to 9.8% at optimum mass flow rate (0.2L/s) and thermal efficiency to (12.3%).

  18. Sixteenth progress report contract to develop an asbestos cement (A/C) cooling tower fill for thermal generating plants. Report no. 23

    1987-01-01

    The author discusses the parameters influencing retention, flexural resistance prior to exposure to aggressive waters, resistance to visible deterioration and flexural resistance after exposure to aggressive waters followed or not by freezing and thawing or by moisture shock exposure, and resistance to visible deterioration and flexural resistance after exposure to freezing and thawing alone. The reduction in moduli caused by the various modes of accelerated weathering exposure was most influenced, for the products of both slags (Algoma Steel and Hamilton slags), by the following parameters, in decreasing order of importance: fibre length, fibre content, and superplasticizer content. The silica content of the fume and the mode of curing had an important influence only on the Algoma slag products. These products showed superior resistance to the Harkart test, which combines severe temperature and moisture shocks. The author discusses density and porosity before and after exposure to aggressive waters. The parameters that most influenced the reduction in porosity were the following, in decreasing order of importance: fibre length, pressing, and the type of aggressive water. 9 figs., 70 tabs.

  19. Water-cooled, fire boom blanket, test and evaluation for system prototype development

    Initial development of actively cooled fire booms indicated that water-cooled barriers could withstand direct oil fire for several hours with little damage if cooling water were continuously supplied. Despite these early promising developments, it was realized that to build reliable full-scale system for Navy host salvage booms would require several development tests and lengthy evaluations. In this experiment several types of water-cooled fire blankets were tested at the Oil and Hazardous Materials Simulated Test Tank (OHMSETT). After the burn test the blankets were inspected for damage and additional tests were conducted to determine handling characteristics for deployment, recovery, cleaning and maintenance. Test results showed that water-cooled fire boom blankets can be used on conventional offshore oil containment booms to extend their use for controlling large floating-oil marine fires. Results also demonstrated the importance of using thermoset rubber coated fabrics in the host boom to maintain sufficient reserve seam strength at elevated temperatures. The suitability of passively cooled covers should be investigated to protect equipment and boom from indirect fire exposure. 1 ref., 2 tabs., 8 figs

  20. Evaluation of water cooled supersonic temperature and pressure probes for application to 2000 F flows

    Lagen, Nicholas T.; Seiner, John M.

    1990-01-01

    The development of water cooled supersonic probes used to study high temperature jet plumes is addressed. These probes are: total pressure, static pressure, and total temperature. The motivation for these experiments is the determination of high temperature supersonic jet mean flow properties. A 3.54 inch exit diameter water cooled nozzle was used in the tests. It is designed for exit Mach 2 at 2000 F exit total temperature. Tests were conducted using water cooled probes capable of operating in Mach 2 flow, up to 2000 F total temperature. Of the two designs tested, an annular cooling method was chosen as superior. Data at the jet exit planes, and along the jet centerline, were obtained for total temperatures of 900 F, 1500 F, and 2000 F, for each of the probes. The data obtained from the total and static pressure probes are consistent with prior low temperature results. However, the data obtained from the total temperature probe was affected by the water coolant. The total temperature probe was tested up to 2000 F with, and without, the cooling system turned on to better understand the heat transfer process at the thermocouple bead. The rate of heat transfer across the thermocouple bead was greater when the coolant was turned on than when the coolant was turned off. This accounted for the lower temperature measurement by the cooled probe. The velocity and Mach number at the exit plane and centerline locations were determined from the Rayleigh-Pitot tube formula.