How Absorption Chillers Work Turn Waste Heat into Usable Energy

The absorption chillers take the excess heat generated by machines, cool it, and turn it into usable energy. There is usually a lot of heat-making machines in factories. And factories are all about getting energy wherever possible. That is why most factories will have an absorption chiller. The absorption chillers first cycle involves refrigerating vapors so that they lose their concentration. This takes place in the evaporator. Most of the time lithium bromide is the absorbing agent used for this. Most companies who utilize an absorption us lithium bromide because it has a high affinity for water, is pretty cheap, and is non-toxic.

Absorption chillers in motor homes usually use ammonia for this agent. The lithium bromide absorbs the evaporated moisture. These refrigerated vapors are then transferred from the evaporator to condenser. Along the way there, the vapors pass through the concentrator where the lithium bromide is re-concentrated. When this re-concentrated fluid reaches the condenser, it is condensed, collected, and reheated. It is called an absorption cycle because of the key absorption of residue vapor. For all of this to work, the absorption chiller has to work at extremely low pressures.

Not all absorption chillers are the same. Although there are differences from one machine to the next, there are generally two kinds of absorption chillers available: 1) Single Effect Units work at the lowest pressure possible. 2) Double Effect Units are gas or steam driven machines operating at high pressure.