How does a cooling tower system work?
Cooling tower systems work by using water to extract waste heat from a system and ejecting it into the atmosphere primarily through evaporation. The three key components of a cooling system are the cooling tower, recirculating pump, and heat exchanger. Water first passes through a heat exchanger where it absorbs heat.
Which method of air circulation is used in indoor cooling tower?
Warm moist air is less dense than drier air at the same pressure. This moist air buoyancy produces an upwards current of air through the tower. Mechanical draft — Uses power-driven fan motors to force or draw air through the tower.
How do you calculate air flow in a cooling tower?
The formula is total heat removed (11.2) times pounds per minute of air (6.95) times 60 minutes per hour. 11.2 X 6.95 X 60 = 4, 670.4 BTU/Hr. Therefore, a tower with a 100 CFM motor at these conditions would be removing 4,670.4 BTU/Hr.
What is the percentage of evaporation loss in cooling tower?
As air rises inside the tower, it receives the latent heat of vaporization from the water, and thus the water is cooled. As a rule of thumb, for every 10°F (5.5°C) of water cooling, 1% total mass of water is lost due to evaporation.
What is the pH of cooling tower water?
7.0
How does the flow of air occur in natural Draught cooling tower?
Explanation: In natural draught cooling tower, the flow of air occurs due to the natural pressure head caused by density difference between the cold outside air and hot humid air inside. This increases the cooling rate by increasing the air velocity over the wet surfaces and through the tower.
What cooling system is used in large power plants?
Most commonly, wet-recirculating systems use cooling towers to expose water to ambient air. Some of the water evaporates; the rest is then sent back to the condenser in the power plant….Types of cooling.
| Natural gas (combined cycle) | |
| Once-through | 20 – 100 |
| Recirculating | 150 – 283 |
| 130 – 300 | |
| Dry-cooling | 0 – 4 |
What is cooling tower fill material?
Fill, or wet deck or surface, is a medium used in cooling towers to increase the surface area of the tower. This enlarged surface area allows for utmost contact between the air and the water, which allowing greater evaporation rates.
What is the advantage of natural Draught over forced Draught?
Advantages of Natural Draught The capital investment is less. The maintenance cost is low as there is no mechanical part. Chimney keeps the flue gases at a high place in the atmosphere which prevents the contamination of the atmosphere. it has a long life.
What is the main advantages of natural Draught?
To supply required quantity of air to the boiler furnace for the combustion of fuel. 2. To remove exhaust gases from the boiler passage to maintain flow of air and gases. 3.
What are the advantages of artificial Draught over natural Draught?
The artificial mechanical draught is better in control and more economical than natural draught. 2. The rate of combustion is high as the available draught is more. The better distribution and mixing of air with fuel is possible therefore the quantity of air required per kg of fuel is less.
What are the limitations of chimney Draught?
1. The maximum pressure available for producing natural draught by chimney is hardly 10 to 20 mm of water under the normal atmospheric and flue gas temperatures. Limitations 3. As there is no through mixing of air and fuel in the combustion chamber due to low velocity of air therefore combustion is very poor.
How many types of Draught are there?
four types
What is natural Draught and mechanical Draught?
Natural draft cooling towers make use of the chimney operation of the cooling tower. The air flow is caused by the temperature difference between the air inside and outside the cooling tower. The fans used in mechanical draft cooling towers cause the air flow. We also supply spare parts for this cooling tower type.
What is the function of Draught?
Draught may be defined as the small pressure difference which causes a flow of gas to take place. In case of a boiler the function of the draught is to force air to the fire and through a boiler furnace and flue, and to discharge the products of combustion to atmosphere via stack or chimney.
Which is most preferred type of Draught system?
10. Which is most preferred type of draught system? Explanation: A balanced draught system combines the features of forced draught and induced draught. In case of forced draught, when the furnace doors are opened high pressure air rushes outside and even blow out the fire entirely.
How does an induced draft fan work?
Industrial induced draft fans operate by focusing the pressure and volume at the inlet of the fan to pull air through a system. Forced draft and induced draft fans often work in concert to maintain efficient and steady air pressure and control the flow using VFDs, dampers, & other accessories.
What is forced draft fan?
Forced Draft Fan is a type of a fan supplying pressurized air to a system. This fan supplies air to the Air-Preheater, where it captures the heat from the flue gases coming from the Boiler Outlet.
What does induced draft mean?
: a draft produced by a suction steam jet or fan on the stack side of a furnace.
What is the difference between a check and a draft?
Checks are drawn by a current account holder of a bank whereas drafts are drawn by one branch of a bank to another branch of the same bank. The signature of the account holder is needed for checks. But drafts do not usually have signatures as they are already signed by an automated machine.
What does draft mean?
1 : to select for some purpose: such as. a : to conscript for military service was drafted and sent overseas. b sports : to select (a professional athlete) by draft got drafted by the Yankees. 2a : to draw the preliminary sketch, version, or plan of draft legislation. b : compose, prepare draft a memo.
What is positive draft?
A positive draft means the angle of the face, with respect to the direction of pull, is more than the reference angle. Negative draft.