How Big Buildings Circulate Air?

Written by Thomas Yoon

How do big shopping complexes, offices and commercial buildings cool their indoor space?

For big buildings, we need big cooling capacities. Central air-conditioning systems using chillers are used. Chilled water isrepparttar most convenient way to collectrepparttar 133435 heat from repparttar 133436 indoor spaces. We just need pipes. Miles and miles of them.

Chilled water fromrepparttar 133437 chillers is about 44 degree Fahrenheit (about 7 deg C). In order forrepparttar 133438 room heat to be transfered torepparttar 133439 water efficiently,repparttar 133440 air inrepparttar 133441 room is circulated through tubes containing flowing chilled water.

That isrepparttar 133442 main function ofrepparttar 133443 air handling unit in a central air-conditioning chilled water system.

Another function of an air handling unit is to cleanrepparttar 133444 air. It does this by filtration.

A most basic air handling unit, or AHU, contains a fan, a cooling coil, and an air filter enclosed in a box-like structure.

Normally, air contains moisture. When air is passed through repparttar 133445 cooling coils, water usually condenses out atrepparttar 133446 surfaces ofrepparttar 133447 coils. Collection pans are installed belowrepparttar 133448 cooling coils to collect any condensed water. This water is removed through drain pipes.

Belts that Squeeze

Written by Thomas Yoon

Belts have many uses inrepparttar running of equipment. The most common belts are used to transmit power from a prime mover (usually a motor) to another rotating machine.

Have you heard of belts used for removing water from sludge?

Yes, there is a type of equipment used in wastewater treatment that uses belts to remove water from sludge. It's called a belt press.

This is how it works:

There are two continuously running belts made of woven polyester material inrepparttar 133434 belt press. There are many freely rotating rollers whererepparttar 133435 belts pass over.

The belts are typically about 2 feet wide, depending on repparttar 133436 design. There is an upper belt, and a lower belt. The arrangement ofrepparttar 133437 belts and their travel onrepparttar 133438 rollers is made in such a way that at some point alongrepparttar 133439 route, they will be placed tightly against one another. The pressing together of these belts squeezes outrepparttar 133440 water fromrepparttar 133441 sludge.

In order to work,repparttar 133442 lower belt is passed through a tank containing a mixture of sludge in water. Asrepparttar 133443 belt travels throughrepparttar 133444 sludge-laden water, some ofrepparttar 133445 sludge gets stuck onrepparttar 133446 upper surface ofrepparttar 133447 belt, and is carried along with it.

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