Cooling Tower

About Cooling Towers and Cooling Tower Manufacturing Including: Air Conditioner Cooling Tower, Cooling Tower Design, Cooling Tower Systems, Evaporative Cooling Towers, Fiberglass Cooling Towers, HVAC Cooling Towers, Industrial Cooling Towers, Natural Draft Cooling Towers & Water Cooling Towers.

Cooling towers, sometimes referred to as heat rejection devices, are systems that provide cooling of water and other fluids through the removal of heat from the fluid. Essentially, a cooling tower is comprised of a water tower and a water reservoir pumping system. Hot process water is fed to a cool water reservoir and then pumped to the process again. Heat in the process water is eliminated as spray nozzles distribute it over the wet deck surface. Air is simultaneously blown upward over the wet deck surface. As the stream of air flows past the heated water, the air absorbs the heat, lowering the water temperature. During the process, some of the water evaporates, which increases the amount of heat transfer. The cooled water is returned to the process after being collected in the reservoir. There are many different methods cooling systems use. Some employ evaporative cooler and HVAC cooler systems to provide a cooling effect. Many are made of fiberglass because of its strength and weather resistance. 

Cooling tower systems produce the airflow through a couple methods. Mechanical draft towers utilize fans located on the sides of the tower in order to create airflow. Forced draft towers have fans located on the side of the cooling towers, while induced draft cooling towers have fans located on the top of the cooling tower to pull air through the tower. Natural draft cooling towers do not use fans but depend upon the rising exhaust air to create the airflow. These cooling towers use very large concrete chimneys and are typically in place only at utility power stations. In some cases, the two methods are used in conjunction with one another to create the required draft of air.

Fill pack is located on the wet deck surface and is the heart of most cooling towers. Cooling tower systems typically use PVC or polypropylene materials for fill, although other materials may be used. The labyrinthine design is formed by individual vacuum formed sheets. The sheets space themselves apart when arranged vertically side-by-side, leaving passageways for water and air. The sheets may press against each other or may be glued together. Strength may be gained by folding the edges. The channels (flutes) formed between the adjacent fill sheets are usually at an angle to vertical in order to increase the "hang time" of the water as it falls through the wet deck.

Cooling tower systems remain beneficial in cooling fluids, particularly water, in a variety of industrial applications. Useful applications for cooling towers include air conditioner cooling towers, dry cleaning, water treatment and power generation. Numerous industries, including water/wastewater, chemical, electric, pulp and paper and plastics industries, utilize the products made by cooling tower manufacturers to reduce heat in industrial facilities and systems. When selecting a cooling tower, consider industrial application, fluid type and volume, tower placement within the facility and environmental factors. Many different cooling tower cooling tower designs remain available to fulfill customer needs. In addition to standard cooling tower designs, many cooling tower manufacturers offer custom cooling tower design services. 

Cooling Tower Types

• Ceramic cooling towers have quite an attractive appearance, but are usually more expensive than other cooling towers.
  
• Closed circuit cooling towers are cooling towers in which the air and cooled water or other fluid do not have direct contact.
  
• Cooling tower design determines cost, performance, and efficiency.
  
• Cooling tower manufacturers are companies that make units that cool fluids.
  
• Counterflow cooling towers contain opposing air and water flows. The airflow moves up and the water flow moves downward.
  
• Cross flow cooling towers contain perpendicular air and water flows. The airflow is horizontal, and the water flows vertically downward.
  
• Disinfection cooling towers are used in drinking water and wastewater treatment facilities to assist in the elimination of bacteria, chemicals and other impurities in the water.
  
• Fiberglass cooling towers have great weather resistance, which makes them useful in harsher environmental conditions. These cooling towers also provide good corrosion resistance, which remains advantageous in applications such as water treatments, in which the tower will be exposed to chemicals.
  
• Mechanical draft cooling towers consist of forced draft towers, which contain side fans that force the air through the system, and induced draft cooling towers, which contain overhead fans that pull the air through the system. Mechanical draft cooling towers are often used in smaller cooling tower systems.
  
• Natural draft cooling towers do not utilize fans but rely on exhaust air buoyancy and natural winds to move the air through the system. Natural draft cooling towers are used in applications involving large volumes of water, such as power generation plants.
  
• Open circuit cooling towers are cooling towers in which water is internally distributed within the system with direct contact with the entering air.
  
• Water cooling towers are basic cooling systems used to cool water through contact with airflow. Applications utilizing water cooling towers include air conditioning and water/wastewater.

Cooling Tower Terms

Ambient Temperature - The DBT as measured by a thermometer.
 
Axial Fans - Fans in which the direction of the airflow does not change. Axial fan types include propeller, tubaxial and vaneaxial.

Blowdown - Water removed from a cooling tower to prevent excessive buildup of impurities within the system. Impurities increase in concentration as water evaporates during the cooling process.
 
Blow Out - Water removed from a cooling tower through wind or splashing. Blow out is reduced or eliminated through the use of screens and other mechanisms.
 
BTU (British Thermal Unit) - The amount of heat gain or loss that is needed in order to change the temperature of one pound of water by one degree Fahrenheit.
 
Drift - Water droplets removed from a cooling tower along with the exhaust air. Drift must be controlled because, unlike the water vapor removed from the tower, drift often contains chemicals, debris and other impurities that may negatively affect the environment.
 
Drift Eliminator - A mechanism in a cooling tower that prevents drift from leaving the tower by catching the drift as it flows through the eliminator, while allowing the passage of exhausted air through the eliminator and into the atmosphere.
 
Dry Bulb Temperature (DBT) - The temperature of the air entering the cooling tower, measured in degrees Fahrenheit.
 
Entrainment - Water in the air being brought into the cooling plumes as the liquid wastes are discharged.
 
Exhaust Air - The air removed from the cooling tower during the cooling process. Exhaust air also contains water vapor that has evaporated during the cooling process.
 
Fill - A labyrinth-like packing that provides a vastly expanded air-water interface, which allows heating of the air and evaporation to occur. Film fill consists of multiple, typically vertical, wetted surfaces upon which a thin covering of water spreads, while splash fill consists of many levels of horizontal splash elements that create a cascade of tiny droplets, which have a large combined surface area.
 
Fogging - The foggy condensation of water vapor outside of a cooling tower resulting from the contact of saturated exhaust air emerging from the tower with cooler air outside of the tower.
 
Induced Draft - The process in which the fan of the cooling tower draws air from the bottom of the unit and passes it out through the top of the cooling tower.
 
Noise - Sound energy generated by the impact of falling water, movement of air by fans, the movement of fan blades within the structure and the drive belts, gearboxes and motors that is emitted by a cooling tower and recorded at a certain distance and direction.
 
Nozzle - A mechanism through which water flows into a cooling tower in either spray or stream form.
 
Plume - Exhaust air and water vapor emerging from a cooling tower. A plume may create fogging when introduced to air of a lower temperature.
 
Psychrometer - Mechanism used in a cooling tower system to measure the wet bulb temperature of the system.
 
Recirculation - The entrance into a cooling tower of previously discharged air that reenters the system along with fresh air.
 
Thermal Capacity - Cooling tower capacity representing the amount of liquid, measured in gallons per minute, that a cooling tower can process.                   
 
Wet Bulb Temperature (WBT) - The temperature within a cooling tower at which the air is saturated with water vapor, preventing the further occurrence of water evaporation.