Absorption chillers

Description

Unlike compression chillers, absorption chillers use absorbers and heat generators instead of compressors. Lithium bromide is the most common coolant in absorption chillers. In this system, in the absorber part, water vapor is absorbed by concentrated lithium bromide, and in the heat generator part, water is converted to steam through heat. Water vapor liquefies in a condenser at a pressure of 0.1 atmospheres and then turns into steam again in a coolant at a pressure of 0.01 atmospheres. The water takes its latent heat from the cooling medium to evaporate, causing it to cool. The water vapor generated in the coolant is then transferred to the absorber, and the cycle is repeated.

Absorption refrigeration technology is an excellent method for central air conditioning in installations that have additional boiler capacity and can provide the steam or hot water needed to operate the chiller. Absorption chillers can easily provide capacities from 25 to 1200 tons of refrigeration. Absorption chillers are a type of cooling/heating device in which the source of energy supply is heat and generator. These types of chillers are called gas chillers. The purpose of the absorption chiller system is to cool and transfer the refrigerant liquid, which is basically water, to different building units such as air conditioners or fan coils or industrial units for cooling.

Refrigerant liquid cooling in this type of chiller is done by heat sources such as hot steam or direct gas flame during the absorption cycle. Absorption chillers generally work in such a way that the gases from the evaporation of the refrigerant liquid are absorbed by the adsorbent, mainly lithium bromide, during the absorption cycle in the primary fluid or evaporator. It should be noted that the adsorbent is known as a secondary fluid.

Different types of absorption chillers:

Absorption chillers have different types that are classified based on various factors.

Absorption chillers are generally classified based on three forms:

1. Absorption chiller classification based on the generator heat source
2. Absorption chiller classification based on refrigerant and adsorbent
3. Absorption chiller classification based on the adsorption solution concentration cycle