Does an absorption chiller need a cooling tower?
The absorption process is exothermic (i.e., it generates heat), and heat must be rejected from the absorber to the condenser water and cooling tower loop. Because of this additional heat rejection load, absorption chillers require a larger cooling tower compared to a mechanical chiller with the same capacity.
How many types of absorption chillers are there?
Looking at Graph 1, all three types of absorption chillers are most efficient at 50% part load with the single-effect indirect-fired chiller having a 9.4% increase in efficiency; the double-effect direct-fired chiller having a 10% increase in efficiency; and the double-effect indirect-fired chiller having a 16.7% …
What material is used in an absorption type chiller?
A simple absorption refrigeration system common in large commercial plants uses a solution of lithium bromide or lithium chloride salt and water. Water under low pressure is evaporated from the coils that are to be chilled.
What are the principles of absorption cooling?
Absorption cooling dissolves a vapour in a liquid (the absorbent), pumps the solution to a higher pressure in the regenerator and then uses heat to evaporate the refrigerant vapour out of the solution. The most common absorption cycle uses water as the refrigerant and lithium bromide (LiBr) as the absorber.
What is COP formula?
COP (Coefficient of Performance) The Co-efficient of performance (COP) is an expression of the efficiency of a heat pump. When calculating the COP for a heat pump, the heat output from the condenser (Q) is compared to the power supplied to the compressor (W). COP = |Q| W.
What is COP in chiller?
Calculating the efficiency of a chiller is fairly simple. It is measured in “COP” which stands for Coefficient Of Performance. The Coefficient of performance is just a ratio of the refrigeration effect produced by the chiller against the amount of electrical energy that went into the machine to produce this.
Which type of chiller is best?
- Water-cooled chillers are generally more efficient than air-cooled chillers.
- They have a quieter operation than air-cooled systems.
- They are suitable for both small-scale and commercial-scale cooling.
- Portable solutions are available for facilities with space constraints.
What is chiller temperature?
Chilled water temperatures (leaving from the chiller) usually range from 1 to 7 °C (34 to 45 °F), depending upon application requirements. Commonly, chillers receive water at 12°C (entering temperature), and cool it to 7°C (leaving temperature).
Why lithium bromide is used in absorption chiller?
Lithium Bromide (LiBr) has the property to absorb water (Refrigerant) due to its chemical affinity. It is directly proportional to concentration and inversely proportional to its temperature. Diluted LiBr loses its capacity to absorb water vapour. Thus, needs to be re-concentrated using a Heat Source.
Is LiBr a refrigerant?
The lithium bromide- water (LiBr-H2O) absorption system mainly constitutes evaporator, absorber, generator, condenser, solution pump, storage tank and expansion valve . When powered by flat plate collector, the water is taken as refrigerant and Lithium Bromide (LiBr) as absorbent.
Why is LiBr used in VAM?
The absorbent of the vapor absorption machine is Lithium bromide (LiBr). LiBr is a highly water attractive chemicals which means it has a great affinity towards water. The higher is the concentration and the lower its temperature, the stronger is the absorption power.
What is absorption chiller how it works?
In short, the absorption chiller chills water via sudden change of pressure. When the water heats up in the generator, the air pressure is high. Water releases the heat and becomes vapor. Then, as it goes through the cooling tower, the vapor cools down in a low-pressure environment and becomes water again.