Frame and casing, fill, cold water basin, drift eliminators, air inlet, louvers. For large cooling towers especially power plants, water treatment is the key area for energy conservation. Chemical treatment of water for cooling and heating systems. 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 lg ratio of a cooling tower is the ratio of the liquid water mass flowrate l to gas air mass flowrate g. Cooling tower blowdown equation by james mcdonald, pe, cwt originally published. The specific configuration of your system will depend on several things, including. They reject process heat from the cooling water to atmosphere and keep the water cool. Preventive maintenance program and plan for cooling towers utica cfmu00018 r1 printed copies are considered uncontrolled. During the cooling tower working process, small volumes of water evaporate. Nov 15, 2014 there are several term in principle of cooling tower need to be focused when conducting this experiment as a basic knowledge to perform experiment perfectly.
Matching the cooling system materials, design, and operation with the water treatment program and water quality is essential for protecting the cooling water. They require specialized maintenance to ensure safe, efficient, and reliable operation, including an effective water treatment program. Basic cooling water treatment treatment can be divided into four steps. Introduction an open circuit or evaporative cooling tower is a heat. Technical information for cooling towers using recycled water.
Armfields uop6mkii computer controlled basic water cooling tower comprises a cooling tower mounted on top of a heated water reservoir. Cooling tower plays a major role in chemical process industry. These tall, opentopped, cylindrical structures are responsible for cooling water generated from industrial or hvac comfort cooling process. However, in the real and practical sense, we seldom see such huge sized cooling towers and mostly smallsized cooling towers are common in use for discharging heat generated by air conditioning systems. As water evaporates in a cooling tower, dissolved solids and suspended solids remain behind. System components include piping infrastructure, valves, pumps, heat exchangers, the cooling tower structure, and cooling. The first of these, the directcontact or open cooling tower figure 3, ex poses water directly to the cooling. Audit and assessment cooling water pretreatment chemical applications monitoring before effective treatment can be provided, a thorough assessment of conditions in your cooling water system must be made. Lab result shows existence of legionella more than 1 one c.
If we start out with fresh water the tower has one cycle of concentration. Cooling towers have certain design values, but seasonal variations require adjustment and tuning of water and air flowrates to get the best cooling tower. For legionella emergency disinfection purposes, an initial 50 ppm. Best practice guidelines 3 best practice guidelines water conservation in cooling towers au 1. Large cooling towers are usually used in industries like power plants, petroleum refineries and various manufacturing facilities. Cooling tower efficiency calculations cooling tower efficiency calculation is described in this article. If you read this book carefully, you can make any cooling tower design programs by yourself. In a counterflow cooling tower, water sprays are used to distribute the warm water see figure 8. Pdf water cooling tower basic cooling tower unit load. As the hot cooling water from exchangers may have explosive gas if a. Introduction overview structure basic cooling tower terms types of towers important properties of water. Operation of the cooling tower as heat rejection device is based on a principle where waste thermal energy is extracted from hot water to the.
Sodium chlorite treatment of cooling water with chlorine dioxide. Cooling tower conductivity controllers model 161fs the model 101 series are basic bleedandfeed cooling tower controllers. An introduction to water cooling towers ced engineering. These controllers are also ideal for closedloop systems when configured with reverse setpoint. Cooling towers are used to remove heat from a building. Dutchess community college cooling tower maintenance program and plan april 1, 2016 5 routine inspection, cleaning and treatment all cooling towers will be subject to monthly inspections. The difference in temperature between the hot water entering the tower and the cold water leaving the tower is the cooling range. Intent in the foreword of cooling tower fundamentals published by marley cooling technologies, inc. Free cooling is when chilled water is cooled by cooling tower water.
Water outputs from a cooling tower include controlled losses such as evaporation, bleed, drift and pump gland leakage and uncontrolled losses including leaks, splash out, overflows and windage. Cooling tower types cooling towers fall into two main categories. 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. Feb 24, 2014 a cooling tower is an essential piece of equipment in many production facilities used to bring down the temperature of the water used in many different process so it can be used again. 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. Cycles of concentration technical term used to describe the mass flow rela. Pdf water cooling tower basic cooling tower unit load tank. Additional facility the water cooling tower may be used to demonstrate industrial practice in which a cooling tower is used to cool water from a process. Technical reference for water conservation in cooling towers. A psychromehic analysis of the air passing through a cooling tower illustrates this effect figure 2. Basic cooling tower terms blowdown water discharged to remove high mineral content system water, impurities, and sediment. The fan at the top of the tower induces a draft, which causes water evaporation and cooling. Suptic air conditioning and refrigeration systems ranging from light commercial to industrial applications may rely on cooling towers.
As the hot cooling water from exchangers may have explosive gas if a heat exchanger is leaky. Audit and assessment cooling water pretreatment chemical applications. Cooling tower calculations cooling water treatment. Course contents evaporative coolers, often called swamp coolers, are cooling systems that use only water and a blower to circulate air. Also brief about cooling tower mass balance of makeup water requirement. 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. Apr 01, 2016 dutchess community college cooling tower maintenance program and plan april 1, 2016 5 routine inspection, cleaning and treatment all cooling towers will be subject to monthly inspections and treatment adjustment during the period of. For purposes of this discussion, we will focus on the most common industrial. Cooling towers are a very important part of many process plants. And you may be surprised to learn that there is much more to these cooling towers. The 2 basic types of fill media are film type fill media spreads the water. The fan deck supports the motor and fan of the water.
In a short summary, the purpose of a cooling tower is to cool down water that gets heated up by industrial equipment and processes. Cooling tower thermal design manual cooling tower technical site of daeil aqua co. The water exits the cooling tower and is sent back to the exchangers or to other units for further cooling. Fundamental understanding is critical for proper operation of cooling water and other systems. The fan deck supports the motor and fan of the water spray system. During the cooling tower working process, small volumes of water evaporate, lowering the temperature of the water thats being circulated throughout the cooling tower. 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. What is a cooling tower water treatment system and how. Cooling a stream of water to a lower temperature using evaporation does this. A basic understanding of the system water distribution shall be established in order to properly operate and maintain a cooling tower on a water. An opencircuit cooling tower, commonly called a cooling tower, is a specialized heat exchanger in which two fluids air and water are. The water balance of a tower or cooling water system involves all of the water inputs and outputs associated with the operation of the system. When all the fresh water is evaporated solids are still in the tower the tower then refills itself with more fresh water and we have twice the solids in the tower.
Cooling towers might be one of the most crucial parts of any industrial process. 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. It is the intent of this manual to provide training in basic water systems, water testing, chemical addition, documentation and safety as per the water treatment program manual. Water treatment basics learn water treatment process. 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. Cooling tower basics calculation formulas cooling tower. When warm, dry unsaturated air is pulled through a water soaked pad, water is evaporated and is absorbed as water vapor into the air.
Mar 11, 2018 size of the cooling tower can vary from a small rooftop unit to huge hyperboloid units as used in nuclear power stations. Cooling towers are common place in building hvac systems, cold storage, industry, etc. Wet bulb the wet bulb temperature of the air entering. Motor is to be provided with protection systems like earth fault relay and over load relay etc. Typical closed loop cooling tower system is shown in figure 7. 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. Today we are going to talk about how you can choose the right cooling tower. It is the intent of this manual to provide training in basic water systems, water testing, chemical addition. Introduction overview structure basic cooling tower terms types of towers important properties of water system calculations factors that limit cycles of. Cooling towers quiz questions hvac certification practice tests. As in the natural draft towers, a crossflow tower figure 11.
Cooling tower performance basic theory and practice subject. Oct 02, 2016 in this topic, we will look at how a cooling tower operates. Chapter 25 deposit and scale control cooling system. Hvac water chillers and cooling towers fundamentals application and operation 2nd edition 2011 by herbert w. Drift eliminators are installed to prevent water entrained in the air from leaving the system. Understanding the different types of cooling towers. 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. As this occurs, a small volume of water is evaporated, reducing the temperature of the water being circulated through the tower. Cooling water treatment for controlling suspended solids, algae growth, etc. The load tank is made of stainless steel having a capacity of approximately 9 liters. Cstn july 2003 l et s take a look at how to calculate cooling tower blowdown. Hvac water chillers and cooling towers fundamentals. This will cover the basic workings of the most common type of cooling tower wet or open which you will find on most commercial high rise and industrial sites.
Cooling tower evaporative cooling system measurement. Consider the surface of a warm water droplet or film in contact with an air stream. In technical terms, cooling towers are engineered and designed based on. However, there are some applications designed to use the cooling tower for free cooling. Types of cooling towers two basic types of evaporative cooling devices are used. From the sump cool water is pumped back to the heat exchanger. Basics cooling tower performance basic theory and practice subject. For the sake of this document, cooling tower systems include open recirculating circuit coolers, fluid coolers, and evaporative coolers, closed evaporative condensers. 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. L mass flow of water entering the cooling tower lbmin. Open or wet cooling towers are the most efficient way to reject heat from the cooling system because the water. Cooling text induced draft towers are also divided into two basic designs. Cooling tower efficiency calculations cooling tower approach. The unit comes complete with the following main components.
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. Cooling is accomplished through the latent heat of vaporization. Air enters at the ambient condition point a, absorbs heat and mass moisture from the water. Energy service company performance contractor hvac. The mixing of warm water and cooler air releases latent heat of vaporization, causing a. One helpful means to that end is the water cooling tower. As the water descends through the packing material it is fancooled, blowing air upwards through the tower. Optimum design and operation of an hvac cooling tower for. What problems are associated with operating a cooling tower system. Cooling tower evaporative cooling system measurement and. To do this, a small pump is installed to circulate cooled water.
Here we explain in full detail how does a cooling tower work, cooling tower working principles with example text, pictures and diagrams. In this article explained about basic concepts of cooling tower, types of cooling towers, formula for cooling tower efficiency. Water savings of cooling tower efficiency measures for use in performance contracts. The goal of this edition is to provide the hvac designer, engineers the building owner and his operating and maintenance staff, the architect, and the mechanical contractor with definitive and practical information and guidance relative to the application. Understanding the basics of cooling tower heat transfer. Technical reference for water conservation in cooling towers 1st edition. Preventive maintenance program and plan for cooling towers. Cooling towers are recirculating water systems used to remove heat from building air conditioning equipment and industrial processes. There are three basic types of cooling water systems.
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