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Cooling Tower
Types of Cooling tower :-Hi friends, hope all of you are doing well. World is still fighting against Corona , so I think we have enough time to gain some knowledge. Now days I am also free to write some useful article for chemical engineers. Hope my articles will helpful for new chemical engineers.
In next article we will study about line sizing of cooling system.
Some of our next articles for Cooling tower design are ,
- Type of Cooling Tower
- Application of Cooling towers
- working of cooling tower
What is Cooling Tower ?
It is a equipment or tower which cool the hot water sing air . This is also heat exchanging equipment which exchange the heat in between air and water. In this type we can decrease the temperature up to the wet bulb temperature .In another words cooling type tower is nothing but a typical heat rejecting device or equipment or a tower which reject the heat of warm water using air (Types of Cooling Tower).
“It is a machine or device which cool the warm water which coming from process” .
It is a typical type of heat exchanging equipment which cool the warm water using direct contact of air with water
–Pharmaguides
How cooling tower works ?
It reject the heat from hot water to the air with direct contact of how water and air and capacity to cool the water is depends on the flow rate of air and wet bulb temperature .
-Pharmaguides
What types of heat transfer take place in a typical cooling towers ?
conduction ,convection and radiation
-Pharmaguides
On which Principle , cooling towers works ?
All types of cooling towers works on principle of evaporative cooling
Pharmaguides
To understand the working of cooling tower , it is necessary to have information of wet bulb temperature .Wet bulb temperature if air is nothing but minimum or lowest temperature of air which can reach by evaporation of water. Depend upon wet bulb temperature we can reduce the temperature of warm water .
in simple words cooling tower working principle is ” heat from warm or hot water is get rejected by air contact and we hot air will get out from tower with some water ”
- Pressure drop calculations
In next article we will study about cooling water line sizing, how to find out design capacity of cooling tower and overall view on cooling tower system design.
This article contain some basic information on Application of Cooling towers,working of cooling tower , Types of Cooling Tower,
Working of cooling towers in one line ?
in one short use principle of evaporative cooling , which mean removal of latent heat from water by evaporation
Pharmaguides
Types of Cooling Towers
Cooling towers can categorize on different basis , on the basis of air flow classification of cooling tower is as follows , or Types of Cooling Tower are as follows ,
- Natural Draft Cooling towers
- Mechanical Draft types of cooling towers
Natural Draft cooling Towers
Natural draft cooling tower is work on natural heat transfer. As we know that there are different types of heat transfer like natural heat transfer , connection ,conduction and radiation .This type is works on natural heat transfer.In this type heat from water is rejected by natural heat transfer. When hot water comes in contact with air , heat from warm water is then rejected by natural air .Hot water is high dense than cold water also hot air is less than cold water.In this condition air and water in opposite directions. Generally this type have towers which contains a tall chimney.
Advantages – (Types of Cooling Tower)air flow is natural so less operation cost than mechanical draft CT .
Disadvantageous – Low heat transfer results in less efficiency.
Mechanical Draft Cooling towers
In mechanical drafts types of cooling towers air is circulate using a mechanical device like fan and blowers .As we know that in natural draft CT air flow is natural , so main disadvantage of natural draft is that we will get less cooling water because natural air flow is low .So if we increase the air flow then heat transfer will more and we get a high capacity of water cooling .So to increase the flow rate of air we need to use a motor with fan. Depending upon draft air flow , mechanical draft cooling towers (Types of Cooling Tower) further classifieds as
- Forced Draft ( Types of Cooling Tower)
- Induced Draft
Induced Draft cooling Towers
In This types of mechanical draft cooling tower , fan with motor is located at the top of tower with gear box or direct connected to shaft of motor. In this type we arrange the motor fan in such way that , air will flow out from tower. In short fan or blower which is at the top or at the entrance of hot water in ,will suck the air from tower and though it in atmosphere. In this way hot air will go out from tower and at high velocity and cold air will come in at low velocity.In this type we forcing the hot air to go out from tower so it called induced draft type tower.
Forced Draft cooling Towers
As( Types of Cooling Tower) we study above in section of natural draft and induced draft types of tower , in natural type air will flow naturally on the basic of density deference and in induced draft we will pull out the air from tower using top mounted fan or blower .But in forced draft cooling towers , we force the air in to the tower .In this type entering velocity is low and existing velocity is high . Exact different or opposite than induced draft tower . This type of
Diffidence between natural and mechanical drafts cooling towers
| Sr Number | Natural Draft | Mechanical Drafts |
| 1 | It required a tall tower than mechanical draft | it dos not required tall tower height as like natural draft |
| 2 | air flow is low or natural | air flow can set by mechanical force |
| 3 | it dos not required fan or blower | it required fan or blower |
| 4 | low heat transfer between water and air | high heat transfer between water and air |
| 5 | To increase capacity need to increase height of tower | to increase capacity we can increase the speed of blower or fan |
| 6 | Cheap in operating cost | high in operating cost |
Diffidence between Induced draft and forced drafts types of cooling towers
| Sr Number | Induced Draft | Mechanical Draft |
| 1 | It pull out the air from Types of Cooling Tower | It forced the air in to theTypes of Cooling Tower |
| 2 | Required low motor power | Required high motor power |
| 3 | air entering velocity is low | air entering velocity is high |
| 4 | air existing velocity is high | air existing velocity is low |
Depends upon direction of air flow ,classification of cooling towers is
- Cross Flow ( Types of Cooling Tower)
- Counter-flow (Application of Cooling towers)
Cross Flow Towers
Cross Flow Towers are most widely use cooling towers. In cross flow types of towers, air and warm water get crass to each other . Water flow from up to down and air flow in horizontal direction to the warm water so it called as crass flow types of towers.In cross flow towers power required to run the fan or blower to get air with high velocity is relatively low as compare to the counter flow towers .Another advantage of cross flow towers is noise level of motor is very low or we can considered it as zero. So there are two main advantages one is required low power to run the motor and noise level is also zero.
Counter-flow Towers
In Counter flow towers as the flow direction of warm or hot water and air is opposite . Air flow opposite in direction to the warm water.As compare to cross flow towers its operating cost is high ,its because power required to the run the fan in counter flow towers is high. Also noise level is high as compare to cross flow towers,(Types of cooling towers ) .
Factors affecting the performance of cooling towers
- Quality of water
- Air flow (Application of Cooling towers)
- Wet bulb temperature of air ( Types of Cooling Tower)
Components of a typical towers
Components of cooling towers is depends on types of cooling towers . But for typical towers the main parts and their function is as below .
- Fan – For air flow ( Types of Cooling Tower)
- Motor – To run the fan and blower (working of cooling tower)
- Tray or Basin – For collection of cold water (Application of Cooling towers)
- Tower – It is main body of different types of cooling towers
- Filling – It is Filling material which increase the heat transfer between air and water
- Inlet Nozzle – It required for warm water in ( Types of Cooling Tower)
- Distributor – It spray the warm water over filling
- Drain nozzle -To drain the water from tray or basin ( Types of Cooling Tower)
- Make up water nozzle -To make up the water which is loss due to evaporation or transfer
Application of Cooling towers
Some useful applications are as follows (Application of Cooling towers)
- Use as to cool the warm water which is heated by condenser ,reactors or any other heat exchangers in chemical industry
- Use too cool the water in HVAC system ( Types of Cooling Tower)
- Use to cool the air in ventilation system in Mall , Picture hall
Hope from above explanation you will get idea about different types of cooling towers ,working principle of cooling towers.In next article we will study about line sizing for all types of cooling towers water .
QNA on Cooling Towers
What is a cooling tower?
A cooling tower is a specialized heat rejection device that removes waste heat from a system by transferring it to the atmosphere through the process of evaporation or convection.
How does a cooling tower work?
Cooling towers work by taking in hot water from an industrial process or air conditioning system and circulating it through a heat exchanger. As the water flows over the heat exchanger’s surface, a portion of it evaporates, carrying away the heat and cooling the remaining water. The cooled water is then recirculated back into the system.
What are the different types of cooling towers?
There are several types of cooling towers, including natural draft cooling towers, mechanical draft cooling towers (which can be further classified as induced draft or forced draft), crossflow cooling towers, and counterflow cooling towers. Each type has its own design and operational characteristics.
What are the main components of a cooling tower?
The main components of a cooling tower include the fill (which promotes contact between air and water for effective heat transfer), the drift eliminators (which prevent water droplets from being carried out with the exhaust air), the fan (for creating airflow), the distribution system (for distributing water over the fill), the water collection basin, and the supporting structure.
What is the purpose of a cooling tower in industrial processes?
The purpose of a cooling tower in industrial processes is to remove excess heat generated by equipment or processes. By dissipating heat into the atmosphere, cooling towers help maintain optimal operating temperatures, prevent equipment damage, and improve overall efficiency.
How are cooling towers used in power plants?
Cooling towers play a crucial role in power plants by providing cooling for steam condensers. The hot water from the condenser is sent to the cooling tower, where it is cooled down through evaporation. This allows the steam to be condensed back into water, which can be reused in the power generation process.
What are the factors that affect the efficiency of a cooling tower?
Several factors affect the efficiency of a cooling tower, including the temperature difference between the inlet water and the ambient air, the flow rate of water, the design and condition of the tower’s components (such as fill and drift eliminators), the fan performance, and the quality of water treatment.
How is the cooling capacity of a cooling tower determined?
The cooling capacity of a cooling tower is typically determined by factors such as the flow rate and temperature difference of the water, the wet bulb temperature of the ambient air, and the tower’s design characteristics. Engineering calculations or software simulations are commonly used to estimate cooling tower performance.
What are some common problems associated with cooling towers?
Some common problems associated with cooling towers include scaling (mineral deposits), fouling (organic and inorganic deposits), corrosion, algae growth, microbiological contamination (such as Legionella bacteria), and fan or motor failures.
How can scaling and fouling be prevented in a cooling tower?
Scaling and fouling can be prevented by implementing effective water treatment programs, which may include chemical treatments to inhibit mineral deposits, regular cleaning and maintenance of the tower components, and proper filtration systems. Monitoring and controlling water quality parameters are also important.
What are some energy-efficient strategies for cooling tower operation?
Energy-efficient strategies for cooling tower operation include optimizing the airflow through proper fan selection and control, improving heat transfer efficiency through the use of advanced fill designs, implementing variable speed drives for fan motors, and utilizing automated control systems to match cooling demand with tower operation.
What are the environmental impacts of cooling towers?
Cooling towers have various environmental impacts, including the consumption of large amounts of water for evaporation, potential thermal pollution of nearby water bodies due to the discharge of warm water, and the emission of noise and drift from the tower. However, efforts are made to minimize these impacts through regulations and advanced cooling technologies.
How is the water in a cooling tower treated and maintained?
Water in a cooling tower is treated and maintained through various processes, including filtration, chemical treatment (such as biocides and scale inhibitors), pH adjustment, and periodic monitoring of water quality parameters. Regular maintenance tasks like cleaning, inspections, and adjustments are also essential.
What is the difference between an open cooling tower and a closed cooling tower?
An open cooling tower is exposed to the external environment, and water is directly exposed to the air for heat exchange and evaporation. In contrast, a closed cooling tower operates in a closed-loop system, where the water being cooled does not come into direct contact with the outside air, helping to minimize water loss through evaporation.
How does a cooling tower contribute to water conservation?
Cooling towers contribute to water conservation by enabling the reuse of water within industrial processes. By cooling and recycling water, cooling towers help reduce the overall consumption of fresh water, especially in water-intensive industries such as power generation or manufacturing.
What are some safety measures to consider when operating a cooling tower?
Some safety measures when operating a cooling tower include implementing regular inspections and maintenance of tower components, ensuring proper access and guardrails for workers, providing training on tower operation and safety protocols, and following guidelines to prevent the spread of harmful bacteria, such as Legionella.
Can a cooling tower be used for heating purposes as well?
Cooling towers are primarily designed for heat rejection, but they can be integrated into heating systems through the use of heat pumps or heat recovery systems. In such cases, the cooling tower helps remove excess heat from one area and transfers it to another area for heating purposes.
How is the performance of a cooling tower measured and evaluated?
The performance of a cooling tower is measured and evaluated using parameters such as the approach (temperature difference between the outlet water and the wet bulb temperature of the air), the range (temperature difference between the inlet and outlet water), the cooling capacity, and the effectiveness (ratio of actual heat transfer to the maximum possible heat transfer).
What are some alternatives to cooling towers for heat dissipation?
Some alternatives to cooling towers for heat dissipation include air-cooled heat exchangers, dry coolers, plate heat exchangers, and heat pumps. These alternatives may be preferred in certain applications where water availability is limited, or environmental concerns associated with cooling towers need to be addressed.
How can cooling towers be integrated into sustainable building designs?
Cooling towers can be integrated into sustainable building designs by incorporating energy-efficient cooling technologies, utilizing water-saving measures such as water recycling and rainwater harvesting, optimizing the tower’s operation through advanced controls and sensors, and implementing green building certifications to ensure overall sustainability goals are met.
Read Also
- Distillation
- Fractional Distillation
- Azeotropic distillation
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- Centrifugal Pumps
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- types of cooling towers pdf
Types of Cooling Tower ,working of cooling tower , types of cooling towers pdf ,Application of Cooling towers ,
