Monroe the questions most frequently asked of a fan engineer about axial flow fans for todays wet cooling towers generally cover. The primary task of a cool ing tower is to reject heat into the atmosphere. Best management practice and guidance manual for cooling towers prepared by jea for the control of pollutants discharged to the sanitary collection system. It is the fifth quantity, g, that is selected by the designer of the cooling tower. The cooling tower must be adequately sized to reject this same amount of heat to the atmosphere. The easy answer is what temperature waterglycol do you need. Questions from the floor at our annual conference and answered by a leading panel of experts within the cooling tower industry. For example, the cooling tower might be specified to cool 4540 m3 hr from 48. 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.
Air flow enters one or more vertical faces of the cooling tower to meet the fill material. The cooling component of this new electricity station is a natural draft cooling tower 200 m high, the tallest cooling tower and the largest shell structure in the world. These studies were complicated by the fact that the cooling tower market is typically driven by one of two powerful, yet often conflicting requirements. Both types function as heat exchangers based on the counter flow principle. The fan deck supports the motor and fan of the water spray system. The merkel theory overcomes this by combining the two into a single process based on enthalpy potential. The cooling towers at biogen idec are the largest users of water in the facility. Inadequate flow rates downcomer flow rates can be so low, relative to pipe size, as to allow air to enter at the pipe discharge. High vol umes of air pass through the tower subjecting compo nents to airborn contaminants. By converting to recycled water, cooling tower customers can secure a droughtproof water supply that.
The water which needs to be cooled only comes into contact with the air in open circuit. Cooling towers are used to reject heat through the natural process of evaporation. Filtration guide cooling towers, evaporative condensers. Cooling tower thermal design manual the early investigators of cooling tower theory grappled with the problem presented by the dual transfer of heat and mass. Air mass flowrate, g the first four parameters are determined by the user of the cooling tower. In this regard, cooling towers are key parts of many power. Warm recirculating water is sent to the cooling tower where a portion of the water is evaporated into the air passing. Cooling towers are usually specified to cool a certain flow rate from one temperature to another temperature at a certain wet bulb temperature. Model cooling tower maintenance program and plan name of facility. The cooling tower cleaning was performed in a safe and environmentally friendly manner. Prevention of significant deterioration air permit. Engineering report and the project design documents. The most common is for a cooling tower that provides the required heat rejection capacity with a high level of reliability at low cost.
An introduction to water cooling towers ced engineering. The fanlaws can be used topredi ctthe pe rformance ofa towerwitha nonstandard motor. Dirty water in your cooling tower fouls chillers, drives up energy costs and encourages the growth of harmful bacteria. Therefore, the cooling tower in albuquerque will be able to extract more process or building heat and will run at a cooler temperature because the dry desert air. In the wl 320 open wet cooling tower, water is sprayed into the tower from above and distributed as widely as possible using baffles. If your requirements are for 90 deg f 32 c then you most likely need a cooling tower or fluid. Best management practice and guidance manual for cooling. Enexio a cooling tower is a device which is used to extract excess heat from the process water stream and rejects this excess heat to the atmosphere. Crossflow is a design in which the air flow is directed perpendicular to the water flow. Cooling towers overcome most of these problems and therefore are commonly used to dissipate heat from watercooled refrigera tion, airconditioning, and industrial process systems. Cooling tower pumping and piping bottom vented downcomer. Simulation of a counterflow and crossflow cooling tower by the stepwise integration method montri pirunkaset abstract the stepwise integration method is an approximation method for determining the water temperature in the fill layers for a counterflow cooling tower and in the fill cells for a crossflow cooling tower. Tips for controlling harmful legionnaires disease bacteria suck it up. Cooling technology institute wtb148 08 routine treatment continuous always preferred o continuous free residuals of 0.
The purpose of a cooling tower is to keep a process from raising temperatures too high were they either can be dangerous or lower the efficiency. Cooling towers entry procedure and permit cooling towers are permit required confined spaces if the atmosphere inside the cooling tower is changed by welding, cutting, burning or the use of solvents or cleaners that cause vapors or fumes within the tower. 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. Technical information for cooling towers using recycled water. The tower takes the heat from the water stream and rejects it to. Neglecting the cooling tower will lead to higher than desired return water temperatures to the system, which will result in higher energy use from two perspectives. Owners of buildings with cooling towers must register their towers, as required by the new york city administrative code section 317.
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 efficiency calculations cooling tower efficiency calculation is described in this article. Pdf design and performance analysis of the cooling tower in the. Cooling tower performance in free cooling applications is dependent upon both the system and cooling tower design. Importance of clean operation cooling tower components must be kept clean and free of obstructions, because temperature matters. Best practice guidelines water conservation in cooling towers au 1. Cooling tower manufactuer, closed circuit fluid coolers, installation and maintenance, more than 40 years in the hvac market. Cooling tower monitoring and environmental compliance. Industrial cooling towers are used to remove surplus heat from water. Cooling towers entry procedure and permit cooling towers are a permit required confined space if atmosphere inside cooling tower is changed by welding, cutting, burning or the use of solvents or cleaners that cause vapors or fumes within the tower all shaded areas must be completed by entry supervisor or entrant o. Types of ice as on any outside structure, ice can form on a cooling tower in the wintertime purely by natural effect. Cooling towers play an integral part in either providing comfort in large commercial buildings or process cooling across an extensive range of applications. 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. One bit of cooling tower terminology that many people find confusing is the notion that a ton of cooling tower capacity is equal to 15,000 btus per hour.
A cooling tower is a heat rejection device which extracts waste heat to the atmosphere through the cooling of a water stream. Cooling tower monitoring and environmental compliance allen hile westlake group lytton lai abb lummus global, inc. By using a cooling tower, the plant is kept safe and operational. This water is often discharged to the sanitary sewer system. In addition, being both a water cooling and an air moving device, a cooling tower can promote the formation of ice by its very operation. Cooling is accomplished through the latent heat of vaporization. They reject process heat from the cooling water to atmosphere and keep the water cool. One helpful means to that end is the water cooling tower. Cooling towers permit required confined space entry permit. F o r m u l a s a n d t a b l es formulasandtables fanlaws. Dutchess community college cooling tower maintenance program and plan april 1, 2016 6 continuous routine treatment will be followed. Both open and closed circuit evaporative cooling towers are available.
Pdf 60 m3h nominal capacity cooling tower was designed, based on the required cooling water parameters in process of the adhesive production in the. Pdf temperature control is a significant requirement in the most industrial process. The answer lies in the ashrae handbookstates that the. Cooling tower systems include all components that provide comfort cooling by rejecting heat to the atmosphere through the evaporative process. Cooling tower efficiency calculations cooling tower approach. Frederick merkel was on the faculty of the technical college of dresden in germany.
As this occurs, a small volume of water is evaporated, reducing the temperature of the water being circulated through the tower. By converting to recycled water, cooling tower customers can secure a drought proof water supply that. The tower basin or remote sump provides a perfect environment for. The towervac quickly removes slime, algae and mud from the sides and floor of your basin or sump. 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 use.
Cooling towers permit required confined space entry permit 1. Cooling towers with open and closed water circuits are available. A simplified method to evaluate cooling tower and con denser performance. Cooling tower evaporative cooling system measurement. We all know that a ton of cooling is equal to 12,000 btus per hour, so how can a ton of cooling tower capacity equal 15,000 btus per hour.
Cooling tower plays a major role in chemical process industry. Cooling towers are a special type of heat exchanger that allows water and air to come in contact with each other to lower the temperature of the hot water. Wet cooling tower is one of the key components of large scale water cooled air conditioning plants, whose efficiency influence the cop of the plant to a large extent. This report is available at no cost from the national renewable energy laboratory at.
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. The compact mnk series cooling towers enable cost effective and energy saving cooling of heat processes in plants of all kinds. Even a marginal improvement in the efficiency of evaporative cooling equipment, heat exchangers and chillers can offer owners significant savings over the lifespan of the cooling systems. New york city health department, office of building water supply oversight. Water flows perpendicular to the air through the fill by gravity. For the sake of this document, cooling tower systems include open recirculating circuit coolers, fluid coolers, and evaporative coolers, closed. 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.
In a counterflow cooling tower, water sprays are used to distribute the warm water see figure 8. Concentrated make up water can also contribute to build up of contaminants on the cooling tower distribution and fill areas which eventually flake off and become suspended in the recirculating water. Simulation of a counterflow and crossflow cooling tower. After the water has been chilled, it is distributed via pumps, pipes, and valves the distribution system to the loads, where a heat exchangerfor example, a cooling coil in an airhandlertransfers heat from the air to the chilled water, which is returned to the chiller.
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