The primary purpose of a cooling tower is to remove heat. Mar 02, 2015 using soft water for cooling tower makeup is less common, however, notwithstanding that this strategy offers significant benefits over the use of hard water. The water that is evaporated at the cooling tower is pure, that is, it doesnt contain any of the dissolved minerals present in the makeup. The industries use cooling water in various processes. Louvers are usually set at an angle to the direction of airflow. A case study by stephen osgood, water conservation unit east bay municipal utility district summary in 1988, providence hospital in oakland, california changed the method it uses to treat the water in two cooling towers, replacing a multiple chemical treatment program with ozone gas treatment. Water sampling of fresh water cooling towers statistics 646. Monitor cooling tower, pumps, motors, fans, drive equipment, and instrumentation and resolve any problems in s timely manner. The heat that is removed is called the latent heat of vaporisation. When needed, a fan boosts air flow across the water, thereby increasing evaporation and heat loss. The main part of the installation is the cooling tower, hav.
On the basis of both the real experiment and the numerical experiment including 1d and 3d model which. Concentration concentration is the increase of impurities in the cooling water due to the evaporative process. Typical modern cooling towers have the following parameters. Wl 320, wet cooling tower, show data sheet pdf file print page. Common cooling tower troubleshooting issues ntt training. This causes pollution of cooling tower water by air pollutants and microorganisms to be insignificant. A cooling tower cannot cool water below the wet bulb temperature. Lab 1b cooling tower performance and sensors for thermalfluid.
The parameters are temperature, flow rate of water, relative. Series 1500 cooling tower cooling towers, evaporative. Cooling tower experiment pavol vitkovic, viktor syrovatka. These sources vary in quality depending on the concentration of dissolved and suspended solids.
A cooling tower chemical is defined as a corrosion inhibitor and scale prevent chemical and a cooling water biocide. If not already known, determine the value of water used in your cooling towers and evaporative condensers. Roth 01ro1, however, found from experiment that the merkel number appears to. An open cooling tower is a heat exchanger that in order to cool down water makes use of the direct contact with the air. What type of cooling tower you have open circulating, oncethrough, or closed loop. Comparison of experiment and models using mizushinas correlations for mass. Three beakers of water were used for this experiment. Emsd will carry out random inspections of fresh water cooling towers and collect water samples for bacterial testings for the purpose of monitoring if the owners of cooling towers have properly discharged their responsibility to properly operate and maintain the cooling towers to ensure that the quality of the cooling tower water is at a satisfactory level. Lab 1b cooling tower performance and sensors for thermal. It accomplishes this though the evaporation of water.
The presence of these pollutants can cause a series of problems. An effective cooling tower water treatment system will provide the right quality of water to your cooling tower, the correct circulation chemistry, allowing it to run efficiently, avoiding problematic deposition, and maintaining a manageable amount of blowdown. Oct, 2016 an effective cooling tower water treatment system will provide the right quality of water to your cooling tower, the correct circulation chemistry, allowing it to run efficiently, avoiding problematic deposition, and maintaining a manageable amount of blowdown. What is a cooling tower water treatment system and how does. The thermal and mass transfer experiment device of the. Cooling tower full 1 abstract cooling tower are use to. The sprinkler output may be impeded resulting in poor distribution. Experimental the tested cooling tower is a forced draft counter. Abstract this experiment was conducted to perform energy and mass balance on the cooling tower system and to observe the effects of one of the process variables on the exit temperature of water.
The term induced draft denotes that air is drawn by fans through the flow of falling water and up and out of the cooling tower. The heat transfer occurs partially thanks to a heat exchange between air and water, but mainly thanks to the evaporation of a small quantity of the water that needs to be cooled. A schematic illustration and photo of the used experimental apparatus are shown in fig. Cooling tower performance and sensors for thermalfluid systems. Drift eliminators are installed to prevent water entrained in the air from leaving the system. The cooling tower is one of the most critical and commonly encountered industrial water treatment systems. From your description, it sounds like you will be utilizing this style unit. The tested cooling tower is a forced draft counter. Water leaks in the process or in the cooling tower itself are uncontrolled water loses that could be considered another form of blowdown.
When a system is closed, the water does not come in contact with outside air. Reducing water use in cooling towers and evaporative. Heat is removed by transferring it to air through evaporation. First i wanted to determine how well newtons law of cooling fit real data. One helpful means to that end is the water cooling tower. The main part of the installation is the cooling tower, having 1. There are cooling towers that create process water that can only be used once, before it is discharged. The tower construction structure in made of steel beams. Experimental study of cooling tower performance using.
By removing these ions with a water softener, the cooling tower is able to run at higher cycles of concentration. Cooling towers as per the definition of cooling technology institute cti, usa a cooling tower is a heat rejection device, which extracts waste heat to the atmosphere though the cooling of a water stream to a lower temperature. Cooling towers summary the cooling tower removes heat from water used in cooling systems within the plant. Pollutants in cooling tower water water that is applied in cooling towers, even when this concerns tap water, often contains salts such as chlorine, sulphates and carbonates, dissolved gases such as oxygen and carbon dioxide and metal ions such as iron and manganese ions. Cooling towers may either use the evaporation of water to remove process heat and cool the working fluid to near the wetbulb air temperature or, in the case of closed circuit dry cooling towers, rely solely on air to cool the working fluid to near. Process results and conclusions cools water by exposing the water particles to air actually perform the experiment better predictive equations 20% heat transfer more consistent temperature reading equipment 80% mass transfer cooling tower experiment system set up objectives. The bench top cooling tower behaves in a similar manner and has similar components to a full size cooling tower. Temperature of hot water and cooling rate lab schoolworkhelper. Cooling tower control problem by james mcdonald, pe, cwt originally published. If the cooling tower s conductivity is above parameters, the risk of scale and corrosion increases. As the water is reuse the water may become corrosive and the tendency of scaling may increase.
Aside from the significant costs and toxicity related to standard treatments, cooling towers dump alarmingly high volumes of water, even during periods of minimal operation. Natural draft cooling towers are intended for cooling circulating water in thermal and atomic power plants and at industrial enterprises. Cooling tower experiment by becca peltzman on prezi. This allows facilities to locate in areas with less water available because the. Cooling tower packing material or fill optimizes the contact of air and water, improving the heat transfer and efficiency of the tower. In a counterflow cooling tower, water sprays are used to distribute the warm water see figure 8.
In a crossflow cooling tower, the hot water basin is used to distribute the warm return water flow uniformly over the tower fill see figure 6. A cooling tower water treatment system is an arrangement of technologies that remove damaging impurities from your cooling tower feed water, circulation water, andor blowdown. The specific configuration of your system will depend on several things, including. Fill is the internal part of a tower where air and water are mixed. Cooling tower experiment supplement august 31, 2011 follow the same procedures outlined in the cooling tower performance experiment 1 except in our case we will be using the cooling tower in the university power plant. For comfort cooling systems, using centrifugal or absorption chillers, the recirculation rate can be. This, in turn, helps conserve the amount of any makeup water or chemicals needed. For water cooling tower experiment, there are several parameters that can be adjusted to observe its effects on the evaporation of water. Tl1 in this equation l is the water flow rate in kgs. The amount of water leaving the tower is very small and easily treated in most industrial waste plants or in municipalities, thus, reducing the.
Using soft water for cooling tower makeup water technology. Reducing water use in cooling towers and evaporative condensers. Cooling tower fundamentals spx cooling technologies. Experimental study of cooling tower performance using ceramic. Cooling experiments with water and foam study into fluegas cooling and fire extinction when deploying caf, firedos, high pressure and low pressure hose lines in offensive interior fire fighting operations version. As a result, there are also various types of cooling towers. Closedcycle wet systems actually require some water withdrawals as makeup water is needed to offset evaporative water loss and cooling tower blowdown and have some thermal discharges as a result of cooling tower. Fill an empty beaker with exactly 150ml of water check sidescale of beaker set up apparatus as shown above. The hybrid cooling tower can serve not only as a dry heat exchanger but also as a wet cooling tower. The series 1500 cooling tower is the industrys most serviceable unit without compromising performance and fit.
Ensure the thermometer is about 2cm above the bottom of the beaker. Clean water act npdes permitting determinations for the. Layout of experimental apparatus temperature is measured by the calibrated 0. In experiment 2, based on the result obtain, we can conclude that the higher the water flowrate, the lower the energy in the form of heat transfer or released and the higher the power the. The cf1200 product will provide the most surface area to allow for maximum heat transfer. The first held 100 ml of water, the second 300 ml, and the third 800 ml. Jan 08, 2015 cooling towers as per the definition of cooling technology institute cti, usa a cooling tower is a heat rejection device, which extracts waste heat to the atmosphere though the cooling of a water stream to a lower temperature. Educational lab teaching equipment wet cooling tower trainer. The cooling tower had two possible makeup water sources. Since water is constantly recycled in a cooling tower, water conservation is also achieved. Monitor the soundness and integrity of ct structure and report issued to maintenance.
Historical data from wastewater treatment plants effluents considered as source waters for the. Drift eliminators are also known as mist eliminators. Oct 26, 2016 a cooling tower water treatment system is an arrangement of technologies that remove damaging impurities from your cooling tower feed water, circulation water, andor blowdown. This water is available from plant wells, municipal supplies, and, increasingly, treated municipal wastewater. Cooling tower calculations water technology report. The heat is released to the air rather than to a lake or stream. Abstract cooling tower are use to remove excess heat that is generated in places such as power station, chemical plants and even domestically in air conditioning units. Nov 15, 2014 disscussion from this experiment, the instrument was used in this experiment is water cooling tower he152 unit. Obviously, all of these special materials add to the capital cost of the tower, which is beyond the scope of this paper. Obtain the rated capacity of the recirculation pumps in the cooling system. Cstn september 2002 a client had a large, threecell cooling tower system that was having problems maintaining conductivity. The height of contact between water and air can be obtained from the following equation yz m k ap g b g. If this is the case, your ammonia system is running through the lower coil section with the cooling tower water surrounding, or flowing over, the outside of the tube bundle and thus condensing the ammonia within the tubes. Conclusion this experiment has been conducted to study the effects of heater power on the exit.
Fundamentals of cooling water treatment panel discussion. With expanded models almost doubling the capacity range and a. For experiment 1 we can conclude that if the value of heater power is increasing the temperature of the cooling range in the cooling tower will increase. Cooling tower issues and troubleshooting approaches the water temperature rises unexpectedly. Calcium hardness is the primary cause of mineral scale deposits that form on heat transfer surfaces. Experimental study on heat and mass transfer in cooling towers 851 12 1 fig. Calcium and magnesium are typically the two primary scale formers in a cooling system. After evaporation of the cooling tower plumes mixing was confirmed by the aerial sampling of the humidity and sulfur dioxide content of the atmosphere, figures 8,9,11,12,14, 15, b5, b6, b8, b9, b, b14, b16, b17, b19, and b20 the mixing of plumes, while the cooling tower plumes were visible, was further shown by the presence of acid. A better understanding of evaporative cooling of water in cooling towers is. The heat picked up in the heat exchanger is returned to the cooling tower where it is rejected to the atmosphere by evaporative and convective cooling.
All cooling towers operate on the principle of removing heat from water by evaporating a small portion of the water that is recirculated through the unit. The thermal design and performance of cooling towers have been abundantly discussed in the literature. The large surface area facilitates evaporation, which lowers the temperature of the water that remains behind. A majority of cooling towers use raw, hard water as makeup. Also, microorganisms that are present in cooling tower water cannot end up in outside air. Hilton h891 bench top cooling tower and its operating principles.
Thermal behaviour of closed wet cooling towers for use with chilled. You can look at this as cooling water fundamentals 101. In a cooling tower the warm water enters at the top and spreads down over numerous vertical panels. The k values for rough and smooth corrugated packings decreased with the increase in pitch, and had a.
We have four excellent speakers who will cover different aspects of cooling water treatment. Of greatest concern is the water and chemical usage connected with cooling towers. A corrosion inhibitor and scale prevention chemical allows the cooling tower to reuse the water. A cooling tower is an installation that retreats heat from water by evaporation or conduction. The heat dissipating capacity of water is equal to the heat absorbing capacity of air in the packing. Evaporative cooling of water in a natural draft cooling tower. This manual is not intended to be allencompassing and thoroughly definitive. Erens of industrial water cooling for the financial support with the fill tests and for. In wet cooling towers the water to be cooled is sprayed over a wet deck surface. Phd thesis wetcooling tower thermal performance evaluation. Miscellaneous mechanical components doehdbk1018293 cooling towers summary the important information in this chapter is summarized below. Column anchor column anchor is a device for attaching the tower structure to the foundation. Cooling towers are used in process industries to cool off effluent water from various heat transfer equipment e. If we combine both equations 7 and 8 above, we have.
The hybrid cooling tower is a combination of the advantages of a wet and a dry cooling tower. Cooling tower water pollution pollutants in cooling tower water water that is applied in cooling towers, even when this concerns tap water, often contains salts such as chlorine, sulphates and carbonates, dissolved gases such as oxygen and carbon dioxide and metal ions such as iron and manganese ions. Normally, the approach is with 7 to 10 degrees of the wet bulb temperature. What is a cooling tower water treatment system and how. Dec 04, 2017 the purpose of a cooling tower is to conserve water. The cooling tower is not appropriate in residential air conditioning systems because this cooling tower could produce minor water loss. This experiment are used to study the operation of cooling tower, to determine average heat and mass transfer coefficient and to examine the effect of various parameter such as feed flow rate, air flow rate, inlet water. Six thermocouples are measuring the air temperature and the other seven the water temperature. A cooling tower is a heat rejection device that rejects waste heat to the atmosphere through the cooling of a water stream to a lower temperature. They are located in areas that are situated after the fill and water sprays and just before the area where the air exits the cooling tower see figures 6 and 8. The data acquisition system used a data logger hp 34970a. Using soft water for cooling tower makeup is less common, however, notwithstanding that this strategy offers. Common cooling tower water treatment problems and how to.