However, due to variations in the water source and their operating in an. Cooling towers are a very important part of many process plants. To move a specified quantity of air through the system, overcoming the system resistance, which is defined as the pressure loss. The technical data has been taken from a mechanical draft cooling tower. It is useful for optimization operation of counterflow cwcts such that to improve the energy efficiency of the overall cooling water system. 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.
Design of mechanical draftcooling tower and determination. This cooling tower quiz module covers the design, calculations, operations and cooling water treatment etc which will be a refresher for the experience. With increasing prices of energy and emphasis on sustainable environment, it is important to ensure that the cooler towers. Assessing the performance of cooling towers and their effect. Cooling tower plays a major role in chemical process industry.
Monroe manager, research and development hudson products corporation houston, texas abstract robert c. A cooling tower is heat removal device that uses water to transfer process waste heat into the atmosphere. Local amendments to the 2015 uniform mechanical code. Design of mechanical draftcooling tower and determination of thermal efficiency prof. Oct 17, 2016 although cooling towers are generally some of the most costeffective cooling mechanisms as compared to other cooling technologies such as many dry air cooling systems, it is still important to monitor your industrial cooling tower efficiency and run it as seamlessly as possible.
This thesis evaluates the economics of alternative cooling tower capacity control methods. Cooling tower fundamentals spx cooling technologies pdf drive. The challenge was to increase cooling without experiencing wetting or buildup in the tower or ductwork. Factors affecting cooling tower performance capacity utilization amount of water circulated range determined by the process it is serving determined by heat load and water circulation rate thus range. Abstract this paper will present results from a recent study of energy efficiency opportunities in an industrial process cooling. The relative accuracy of welldefined monodisperse approximation is about several percent of heat efficiency of the cooling tower. Energy efficiency of cooling towers may 9, 2018 wednesday 7. The upgraded tower has been running successfully for approximately 2 years. Warm recirculating water is sent to the cooling tower where a portion of the water is evaporated into the air passing. 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. Cooling tower efficiency cooling tower efficiency can be expressed as efficiency 100t1t2t1t3 where t1 inlet temperature of water to the tower t2 outlet temperature of water from the tower t3 wet bulb temperature of air. Cooling towers are used to reject heat through the natural process of evaporation. See the more detailed explanation of cooling towers systems, diagrams, pictures and principles below table of contents what is a cooling tower how do cooling towers work.
High efficiency chillers can produce chilled water using less than 0. Water conservation in cooling towers au best practice guidelines intent this document has been prepared to assist the owners and operators of cooling towers and evaporative cooling systems in reducing the water consumption of cooling systems while retaining required performance. The efficiency of a tower is based on the original design conditions as well as the type of tower evaporative, draft driven. Cooling towers overcome most of these problems and therefore are commonly used to dissipate heat from watercooled refrigera tion, airconditioning, and industrial process systems.
Since the cooling towers are based on the principles of evaporative cooling, the maximum cooling tower efficiency depends on the wet bulb temperature of the air. A refrigeration system must also reject the heat that it removes using a cooling tower for water cooling the condenser most efficient or using fans for air cooling the hot refrigerant of the condenser coil. 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. Here we explain in full detail how does a cooling tower work, cooling tower working principles with example text, pictures and diagrams. At 100% cooling efficiency, the temperature drop across the evaporative cooler would be. Cooling tower evaporative cooling system measurement and. The tower takes the heat from the water stream and rejects it to. Improving efficiency is, of course, the primary reason for extensive and continuing research and development by cooling tower manufacturers, and subsequent. To capitalise upon the inherent energy efficiency of cooling tower systems the condenser water, and cooling tower systems must be properly designed, operating correctly and regularly maintained. This includes determination of cycle of concentration, evaporation loss, drift or windage loss, blow down water requirement makeup. Cooling tower measurement and verification technical advisory group. Energy savings variable frequency drives and cooling tower.
Crossflow towers should be specified when the following specifications are important. Understanding the basics of cooling tower heat transfer. The cooling tower must be adequately sized to reject this same amount of heat to the atmosphere. Performance analyses of counterflow closed wet cooling towers. Both tower systems are designed to a required cooling tower duty thus the thermal performance and cooling capability for both tower systems, if designed well, are equal. Improving cooling tower fan system efficiencies by robert c. The wetbulb temperature is a type of temperature measurement that reflects the physical properties of a system with a mixture of a gas and a vapor, usually air and water vapor. Pdf temperature control is a significant requirement in the most industrial process. Capacity the amount of water gpm that a cooling tower will cool through a specified range, at a specified approach and wetbulb temperature. Cooling tower bureau of energy efficiency 9 figure 7. Cooling tower systems include all components that provide comfort cooling by rejecting heat to the atmosphere through the evaporative process. Cooling tower performance in free cooling applications is dependent upon both the system and cooling tower design. Monroe graduated from the university of houston in 19. They can achieve water temperatures below the dry bulb temperature tdb of the air cooling air but not the wet bulb temperature.
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. Chemical engineering site already published articles on cooling tower components and cooling tower efficiency calculations. The paper reports on a new approach to improving the performance of existing cooling towers, the oriented sprayassisted cooling tower osact, and shows how facts has been used to evaluate the. 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. It is then combined with makeup water, which replaces the evaporated water, and is sent through the system again. There are multiple ways you can ensure that cooling towers are energy efficient. How to optimize the energy efficiency of cooling towers back to news when evaluating the success of any piece of industrial equipment, the main thing many people consider is the equipments priceperformance ratio how much it costs to operate the equipment weighed against with its ability to do its job, or simply called efficiency. Ajit prasad dash1, kishor kumar panda2, ajay kumar yadav3. The technical data is taken for mechanical draft cooling tower. Cooling towers use the evaporation to cool the circulated water. Hvac and refrigeration system bureau of energy efficiency 71 syllabus hvac and refrigeration system. How to optimize the energy efficiency of cooling towers.
Abstract this paper presents detailed methodology of a induced draft cooling tower of counter flow type in which its efficiency, effectiveness, characteristics are calculated. A simplified thermal modelling of cooling tower for. This system sends cooling water out of the equipment and into a pond or cooling tower, which is open to the atmosphere. The design of the distribution system affects the pump head to bring the hot water to the tower inlet. The present paper is a detailed methodology for thermal design of cooling tower. Side stream filtration systems can be a cost effective method. The fanlaws can be used topredi ctthe pe rformance ofa towerwitha nonstandard motor. Best practice guidelines water conservation in cooling towers au 1. These factors can significantly reduce the efficiency of the cooling towers. 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.
For example, a cooling tower sized to cool 4540 m3hr through a. The primary task of a cool ing tower is to reject heat into the atmosphere. An opencircuit cooling tower, commonly called a cooling tower, is a specialized heat exchanger in which two fluids air and water are. All cooling towers operate on the principle of removing heat from water be evaporating a small portion of water that is recirculated through the unit. Again, this will be a first issue releasing the actual engineering approach. Sep 17, 20 cooling tower energy efficiency maximizing the energy efficiency of a cooling system requires evaluation of the entire cooling system cooling tower, chiller, heat exchangers, etc. Fan energy requirements are determined for counterflow and crossflow towers designed for low initial cost and for energy efficiency. Cooling tower efficiency calculations cooling tower efficiency calculation is described in this article. Nov 30, 2016 cooling tower is an essential piece in most of the chemical process industries and in hvac applications. Cooling tower basics calculation formulas cooling tower. Study the factors on which efficiency of cooling tower can be. While initial results were promising, extended operation with.
Pdf 60 m3h nominal capacity cooling tower was designed, based on the required cooling water parameters. Rp m 2 rp m 1 cfm 2 c fm 1 staticpressure 2 static pressure 1 cfm 2 cfm 12. With the introduction of counterflow cooling towers with high efficiency film fill to the power industry, the technology was applied to geothermal power plants. The overall efficiency of a cooling tower is directly related to the design of the towers water distribution and heat exchange surface. 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. Understanding wet bulb temperature and other aspects that affect evaporative cooling tower performance a cooling tower primarily uses latent heat of vaporization evaporation to cool process water. Cooling towers are an essential component of every building. Cooling tower efficiency calculations cooling tower approach. Cooling tower operation is one of the largest water and energy consuming activities within. Annual fan electrical energy requirements are calculated for towers with singlespeed, twospeed, and variablespeed fans. Water savings of cooling tower efficiency measures for use in performance contracts. If you read this book carefully, you can make any cooling tower design programs by yourself. If we were to consider the significance of the power savings using variable frequency drives on your.
Although cooling towers are generally some of the most costeffective cooling mechanisms as compared to other cooling technologies such as many dry air cooling systems, it is still important to monitor your industrial cooling tower efficiency and run it as seamlessly as possible. Three out of the original eight cooling towers were destroyed, and the remaining five were severely damaged. Improving cooling tower fan system efficiencies robert c. Cooling towers and cooling tower parts spx cooling. Cooling towers are an integral component of many cooling systems that provide comfort or process cooling. A very important concept for understanding cooling tower heat transfer is that of wet bulb temperature, which is the lowest temperature that can be achieved by evaporative cooling. For nearly a century, we have provided exceptional quality equipment and service to the hvac, process cooling, industrial, and. Maximum cooling tower efficiency is limited by the wetbulb temperature of the cooling air. Muller center for advanced energy systems rutgers, the state university of new jersey abstract traditionally, energy recommendations from energy audits have been concerned with the energy. The purpose of this test procedure is to describe instrumentation and procedures for testing and performance evaluation of cooling towers. The primary task of a cooling tower is to reject heat into the atmosphere.
Pdf design and performance analysis of the cooling tower in the. How to optimize the energy efficiency of cooling towers back to news when evaluating the success of any piece of industrial equipment, the main thing many people consider is the equipments price performance ratio how much it costs to operate the equipment weighed against with its ability to do its job, or simply called efficiency. He be came a registered professional engineer in 1966, and is a member of asme, the. Drift eliminators are also known as mist eliminators. Design of mechanical draftcooling tower and determination of. Index terms emissions, downcomer, efficiency, gas cooling, process improvement, mercury removal, spray nozzles. Course contents evaporative coolers, often called swamp coolers, are cooling systems that use only water. For nearly a century, we have provided exceptional quality equipment and service to the hvac, process cooling, industrial, and refrigeration markets. Introduction an open circuit or evaporative cooling tower is a heat rejection device that rejects heat to the atmosphere by cooling a water stream to a lower temperature.
Most geothermal steam plants use crossflow mechanical draft cooling towers with splash fill. Cooling tower evaporative cooling system measurement. Cooling tower operation and maintenance for improved energy efficiency 2009 cti sponsored educational program seismic design requirements for cooling towers 2012 cti educational session ahr expo ac wc systems 2012 cti educational session ahr expo energy water nexus 20 cti educational session ahr expo ac wc systems. Energy efficiency in industrial process cooling systems.
Cooling tower systems operation is most efficient when their heat transfer surfaces are clean. Energy savings variable frequency drives and cooling tower fan motors reduced power consumption is a common goal for all of us. The cooling tower test is conducted in reference with cti code atc 10500, schedule ii performance. As this occurs, a small volume of water is evaporated, reducing the temperature of the water being circulated through the tower. They reject process heat from the cooling water to atmosphere and keep the water cool. In summer the ambient air wet bulb temperature raises when compared to winter thus limiting the cooling tower efficiency. Cooling tower efficiency calculations along with approach, range, cycle of concentration, blowdown, evaporation loss and makeup water. Assessing the performance of cooling towers and their. Cooling towers are a very important part of many chemical plants. In this article explained about basic concepts of cooling tower, types of cooling towers, formula for cooling tower efficiency. Cooling tower is an essential piece in most of the chemical process industries and in hvac applications.
Thermal performance of a cooling tower depends principally on the entering air wetbulb temperature. F o r m u l a s a n d t a b l es formulasandtables fanlaws. The entering air drybulb temperature and relative humidity, talcen independently, have an insignificant effect on thermal verformance of mechanicaldraft cooling towers, but do affect the rate of water evaporation in the cooling tower. Your cooling tower fan motors may offer savings youve not yet uncovered. Cooling tower efficiency calculations chemical engineering site. Vapor compression refrigeration cycle, refrigerants, coefficient of performance, capacity, factors affecting refrigeration and air conditioning. How to increase your industrial cooling tower efficiency. Guide for energy efficient cooling tower design and operation. Unlike tall cooling towers used in large conventional plants, the cooling tower performance does not. Assessing the performance of cooling towers and their effect on chiller efficiency donald kasten and michael r.
1453 1528 995 220 867 54 1147 1268 851 783 900 177 406 449 938 1178 690 1431 556 66 384 875 456 1038 1326 7 441 43 801 1223 742 1166 1458 1452 232 1496 395 567 839 474