Cooling tower control problem by james mcdonald, pe, cwt originally published. Those responsible for the specifications, purchasing and operation of plant, station, or building cooling. The technical data is taken for mechanical draft cooling tower. Range hot water temperature cold water temperature cooling tower efficiency calculation. Design of mechanical draftcooling tower and determination.
See the more detailed explanation of cooling towers systems. At these condi tions, the cooling tower rejects 15,000 btuih per nominal cooling tower ton. Drift eliminators are installed to prevent water entrained in the air from leaving the system. In every application the target portion of the nozzle should be located at the correct distance above the top of the cooling tower fill to obtain maximum. Cooling towers make use of evaporation whereby some of the water is evaporated into a moving air stream and subsequently discharged into the atmosphere. Closed circuit systems differ in that the return fluid often water, or sometimes water mixed with glycol circulates through the tower structure in a coil, while cooling tower water recirculates only in the tower.
Doc boiler efficiency and cooling tower efficiency engr. Drift loss of the cooling tower is normally provided by the cooling tower manufacturer based on the process design. This section provides an introduction of cooling tower designs. Cooling tower pdf, free cooling tower pdf software downloads, page 2. Which cooling tower is best for tropical climates the climate conditions can somehow affect the performance of cooling towers due mainly to the fact that they make use of the surrounding air as well as water supply to do their job. An introduction to water cooling towers ced engineering. Doc air pendingin cooling water makalah disusun untuk. The easy answer is what temperature waterglycol do you need. As with biological growth, sedimentation and scaling of tower surfaces reduce the overall heat transfer coefficient and the cooling capability of the tower, as illustrated in figure 2. Water treatment for cooling towers 1 of 2 water treatment helps ensure that heattransfer surfaces perform to design specifications by amanda meitz, senior microbiologist, nalco diversified technologies, inc.
Cooling tower process tower basin distribution deck basin tower fill induced draft fan recirc pump return water supply water a tower cools water by evaporation by drawing high volume air across the water surface, which transfers heat to the atmosphere. If you continue browsing the site, you agree to the use of cookies on this website. Sep 17, 20 if a cooling tower is discharging blowdown from the cooling tower basin or cooling water supply pipe, a simple piping change to discharge blowdown water from the cooling water piping returning hot water to the tower can provide a 12% improvement in the energy efficiency of the hvac cooling system. Dec 25, 2011 a cooling tower is an equipment used to reduce the temperature of a water stream by extracting heat from water and emitting it to the atmosphere. Here we explain in full detail how cooling towers operate with example text, pictures, diagrams and principles. Mar 20, 2009 well this was the presentation on cooling towers that i created for my own presentation. Minerals can form deposits or scale on the tower materials. Wet versus dry cooling towers cooling technology institute. The evaluation provides a characterization of side stream filtration technology, describes typical applications, and details specific types of filtration technology. Cooling towers overcome most of these problems and therefore are commonly used to dissipate heat from watercooled refrigera tion, airconditioning, and industrial process systems.
Pdf to word converter is a free windows application to convert pdf. Rp m 2 rp m 1 cfm 2 c fm 1 staticpressure 2 static pressure 1 cfm 2 cfm 12. If not already known, determine the value of water used in your cooling towers and evaporative condensers. Design of mechanical draftcooling tower and determination of. Water treatment for cooling towers 1 of 2 email a colleague. Sect 6a2 cooling tower fill replacement energy northwest. Today we are going to talk about how you can choose the right cooling tower system for areas with tropical climates.
The below writeup identifies accepted guidelines for. Install the cooling tower according to the following procedure. Cooling tower basics and common misconceptions introduction in comparison with most other industrial equipments, the water cooling tower is a simple device, based on the direct contact of two of the earths most common substances. Cooling tower bureau of energy efficiency 5 syllabus cooling tower. The wl 320 wet cooling tower is intended to demonstrate the qualitative and quantitative functioning and characteristic variables of a cooling tower. Tower maintenance and operation levels also can influence the formation of drift droplets. The project deals with the performance study and analysis of induced draft cooling tower, which is one of the deciding factors used for increasing the power plant efficiency also modelling and analysis of flow using software. Apr 27, 2017 the basics of cooling tower water treatment the basics of cooling tower water treatment the purpose of a cooling tower is to remove the heat generated by an hvac system cycles is a comparison of the chloride content in the sump water versus the makeup water. Jea, as the control authority, is required to regulate cooling tower discharges to the potw. If your requirements are for 90 deg f 32 c then you most likely need a cooling tower or fluid cooler. 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 calculation of cooling tower efficiency involves the range and approach of the cooling tower. Cooling tower pdf software free download cooling tower.
Method for analysis of ultimate heat sink cooling tower. Types and performance evaluation, efficient system operation, flow control strategies and energy saving opportunities, assessment of cooling towers 7. The belt reducer shall stand and avoid flat laying, in avoidance of crashing or. Some tolerance needed to be minor adjusted on the basin.
The fanlaws can be used topredi ctthe pe rformance ofa towerwitha nonstandard motor. For the tower piping circuit, the pump must overcome the piping flow friction loss. For example, a cooling tower sized to cool 4540 m 3hr through a. Water vapor evaporates, leaving dissolved or suspended solids in the recirculating cooling water. Cooling tower efficiency calculations cooling tower approach.
Cooling towers are an integral component of many cooling systems that provide comfort or process cooling. The three basic requirements set forth in that document. For extended lifts over 25 feet in height, use fabric slings underneath the cooling tower and. Again, this will be a first issue releasing the actual engineering approach. For large cooling towers especially power plants, water treatment is the key area for energy conservation.
For example, excessive water flow, excessive airflow, and water bypassing the tower drift. Best management practice and guidance manual for cooling. The major concern during i study the cooling tower theory was how to computerize the cooling tower theory from the calculation of ntu to the cooling tower performance analysis. 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. Cooling tower performance basic theory and practice subject.
Belt reducer shall be placed in cool, ventilating and safe places, in avoidance of rusting or loss. A presentation on cooling tower renovation work slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. They can act as heat exchangers for chiller systems in heating, ventalation, and air conditioning hvac applications, or they can be used in heat exchange processes in other industries such as power generation, manufacturing, and in. Cooling towers wear out a repack is a normal process in the life of a cooling tower there are several items that can affect the longevity of the fill and tower age of material type of tower materials used in construction weather ice, wind, and, sun water chemistry chlorine and ph plants of our generation have or are currently. Intent in the foreword of cooling tower fundamentals published by marley cooling technologies, inc. The term cycles of concentration compares the level. Cooling tower location criteria cooling tower spacing requirements for multiple tower sites when there are several cooling towers located on one site, the proper placement of the towers in relation to each other is an extremely important consideration. We are a nonprofit group that run this website to share documents.
Tower water must also be evaluated for solids and mineral content. If you read this book carefully, you can make any cooling tower design programs by yourself. Best management practice and guidance manual for cooling towers. The cooling tower had two possible makeup water sources. Training session on energy equipment cooling towers presentation from the energy efficiency guide for industry unep. The water consumption rate of a cooling tower system is only about 5% of that of a oncethrough system, making it the least expensive system to. Other factors, which we will see, must be stated along with flow rate m3hr. All of the required measured values are acquired by sensors and shown on digital displays. Use guide lines as necessary, to prevent damage to the cooling tower, and as a safety measure to control and avoid sudden shifts or movements of the load. In a welldesigned and welloperated power plant, the condensercooling system has an important role in the generating capacity and efficiency of the plant.
As evaporation continues, the water becomes more concentrated than the original make up water. A cooling tower is a heat rejection device which rejects waste heat to the atmosphere through the cooling of a water stream to a lower temperature. The hybrid cooling tower is a combination of the advantages of a wet and a dry cooling tower. Splash fills disintegrates the hot water from vertical direction and it splits the water to pass through next level of splash bars. The thermal capability of a cooling tower used for air condition ing is often expressed in nominal cooling tower tons. Scribd is the worlds largest social reading and publishing site. Chapter 8 cooling towers system shutdown and start.
Cooling tower efficiency is limited by the ambient wet bulb temperature. As the universal solvent, water is capable of dissolving a variety of materials as well as holding. Suptic air conditioning and refrigeration systems ranging from light commercial to industrial applications may rely on cooling towers to remove waste. A pc is used to evaluate the results of the experiments. The basics of cooling tower water treatment the purpose of a cooling tower is to remove the heat generated by an hvac system cooling of compressor refrigerant and heat generated by the compressor itself. Nominal tower dimensions nominal tower dimensions is dimensions used to indicate the effective size of cells, or cooling tower. Effective thermal design of cooling towers a stepbystep approach to cooling tower design, with an example calculation to make it clear jonny goyal air liquide engineering and construction, lurgi india various misconceptions arise when it comes to the thermal design of cooling towers. Cooling tower discharges present a potential problem to the treatment of sanitary sewer and sludge quality especially for the biosolids reuse facility. The hybrid cooling tower can serve not only as a dry heat exchanger but also as a wet cooling tower.
Closed circuit systems differ in that the return fluid often water, or sometimes water mixed with glycol circulates through the tower structure in a coil, while cooling tower water recirculates only in. Pdfcamp pdf writer installs as a printer driver, making the creation of pdf documents as easy as printing. It accomplishes this by providing intimate mixing of water and air, which results in cooling primarily by evaporating approximately 1 % of the flow for each 10. Drift eliminators are also known as mist eliminators. A water balance for a cooling tower can be summarised as. Cooling tower cycles of concentration as pure water is evaporated, minerals are left behind in the recirculating water. If your requirements are for 90 deg f 32 c then you most likely need a cooling tower or fluid. Cooling tower outlet temperature is called cooling tower range. A guide to troublefree cooling towers a basic understanding of cooling tower operation and maintenance will help keep a cooling water system running in top condition, year after year by david m. A cooling tower is a heat rejection device which rejects waste heat to the atmosphere through the cooling of a. Cooling is accomplished through the latent heat of vaporization. If a cooling tower is discharging blowdown from the cooling tower basin or cooling water supply pipe, a simple piping change to discharge blowdown water from the cooling water piping returning hot water to the tower can provide a 12% improvement. If it is not available it may be assumed as for natural draft cooling tower d 0. Vibration monitoring of cooling towers applications cooling tower fans have uses in multiple industries.
It must also provide the energy head necessary to raise water from a low to a higher static head level. F o r m u l a s a n d t a b l es formulasandtables fanlaws. One helpful means to that end is the water cooling tower. Reducing water use in cooling towers and evaporative condensers 3 with cooling towers, it is worth checking whether the water actually used is in balance with what should be used. As this occurs, a small volume of water is evaporated, reducing the temperature of the water being circulated through the tower. Chiller vs cooling tower we often get the question as to when to use a chiller andor cooling tower for process cooling. Cstn september 2002 a client had a large, threecell cooling tower system that was having problems maintaining conductivity. However, due to variations in the water source and their operating in an.
Inadequate flow rates downcomer flow rates can be so low, relative to pipe size, as to allow air to enter at the pipe discharge. To reduce the drift from cooling towers, drift eliminators are usually incorporated into the tower design to remove as many droplets as practical from the air stream before exiting the tower. A cooling tower is a specialized heat exchanger in which air and water are brought into direct contact with each other in order to reduce the waters temperature. Cooling tower pdf software free download cooling tower pdf.
The technology evaluation assesses side stream filtration for cooling towers. Cooling tower systems operation is most efficient when their heat transfer surfaces are clean. A cooling tower is an equipment used to reduce the temperature of a water stream by extracting heat from water and emitting it to the atmosphere. The present paper is a detailed methodology for thermal design of cooling tower. In a welldesigned and welloperated power plant, the condenser cooling system has an important role in the generating capacity and efficiency of the plant.
Cooling towers1 free download as powerpoint presentation. Cooling tower fill is the main heat transfer area available for heat transfer from hot water to cold air. Reducing water use in cooling towers and evaporative condensers. Makeup water means water added to the cooling tower system on a regular basis to replace water lost. Reducing water use in cooling towers and evaporative. Range range is determined not by the cooling tower, but by the process it is serving. Air pendingin cooling water makalah disusun untuk memenuhi tugas mata kuliah. Rp m 2 rp m 1 cfm 2 c fm 1 staticpressure 2 static pressure 1 cfm 2 cfm 12 ho rsep ower 2 ho rsepow er 1c fm cfm 3 formulas. In the horizontal plane, they refer to the approximate width and length of packed areas, and in the vertical plane. Chapter 8 cooling towers system shutdown and startup. Pdfcamp pdf writeris the quick and easy pdf creator software that converts any type of printable windows document, including doc, xls, ppt, txt and even html, to pdf file with the click of a button. Cooling tower pumping and piping bottom vented downcomer.
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