How does the water / lithium-bromide absorption cooling process work?

Question

I fully know and understand how the Ammonia / Water absorption process works.

I even understand how the Ammonia / Calcium Chloride absorption process works.

But in their case, Ammonia is the refrigerant. It has a boiling point of -33 Degrees Celsius. It's understandable that when it evaporates, it takes away heat.

But in the water / lithium-bromide process, water is the refrigerant. I understand that the pressure is lowered to allow the water to evaporate, but how cold can it get? Will it bring down the temperature of the surrounding area to freezing?

Also, if pressure is brought down, what kind of piping is used? Doesn't it have to be strong to withstand the pressure being much higher on the outside than the inside?

Answer 1

see the following article.....be sure to read the "Next" page on this article also for a working diagram of the system.

http://www.tpub.com/content/fc/14104/css/14104_198.htm

Answer 2

Like the compressor in an electric vapor compression cycle, the absorption system uses its "thermal" compressor (consisting of the generator, absorber, pump and heat exchanger) to boil water vapor (refrigerant) out of a lithium bromide/water solution and compress the refrigerant vapor to a higher pressure. Increasing the refrigerant pressure also increases its condensing temperature. The refrigerant vapor condenses to a liquid at this higher pressure and temperature. Because this condensing temperature is hotter than the ambient temperature, heat moves from the condenser to the ambient air and is rejected. The high-pressure liquid then passes through a throttling valve that reduces its pressure. Reducing its pressure also reduces its boiling point temperature. The low-pressure liquid then passes into the evaporator and is boiled at this lower temperature and pressure. Because the boiling temperature is now lower than the temperature of the conditioned air, heat moves from the conditioned air stream into the evaporator and causes this liquid to boil. Removing heat from the air in this manner causes the air to be cooled.

The refrigerant vapor then passes into the absorber where it returns to a liquid state as it is pulled into the lithium bromide solution (the absorption process). The diluted lithium bromide solution is pumped back to the generator. Because lithium bromide (the absorbent) does not boil, water (the refrigerant) is easily separated by adding heat. The resultant water vapor passes into the condenser, the absorbent solution returns to the absorber, and the process repeats.

Answer 3

What Is Lithium Bromide