LiBr Absorption Chiller Cycle: A Deep Dive into Lithium Bromide Technology


Quick Links: The 4-Stage Cycle | Single vs.Double Effect | The BROAD Edge | Get Guidance


How do facilities achieve powerful cooling without massive electricity bills ? The answer is the lithium bromide(LiBr) absorption chiller an elegant technology that transforms heat into cold using chemistry, not compressors.

The Chemistry: No Compressors Required

Instead of synthetic refrigerants and high - power motors, LiBr chillers use two safe, stable substances:

  • Water: Acts as the refrigerant (eco-friendly).
  • Lithium Bromide: Acts as the absorbent (a molecular sponge).

The result ? Zero GWP, Zero ODP , and non-toxic operation ideal for industrial and commercial safety.

The 4 - Stage Magic: Creating Cold from Heat

The cycle operates under a high vacuum(approx. 1 / 100th atmospheric pressure), allowing water to boil at just 4 - 7°C.

1. Generator(Separation):

Heat source(Steam / Gas / Exhaust) boils the dilute LiBr solution.Water vapour separates, leaving concentrated LiBr behind.

2. Condenser(Liquefaction):

Water vapour travels here and is cooled by cooling tower water, condensing back into liquid refrigerant.

3. Evapourator(Cooling Creation):

The Core Step: Liquid water enters the high-vacuum chamber and boils instantly at 4°C. This evapouration pulls heat from your building's chilled water loop.

4. Absorber(Reset):

Concentrated LiBr sprays into this chamber, absorbing the water vapour from the evapourator to maintain the vacuum.The solution returns to the generator to restart the cycle.

Single - Effect vs.Double - Effect

Type Heat Source Performance(COP)
Single - Effect Hot Water(80 - 95°C)
Low Pressure Steam 		0.7 - 0.75
Double - Effect High Pressure Steam
Direct Fired(Gas / Oil) 		1.2 - 1.4

Why BROAD Leads in LiBr Technology

With 35,000 + units globally, BROAD has engineered solutions to the common pitfalls of absorption technology:

  • 🛡️ Corrosion Immunity: LiBr can be corrosive. BROAD uses proprietary inhibitors and oxygen-free welding to ensure 25+ year life.
  • ❄️ Crystallization Prevention: Auto-monitoring prevents solution solidification, a common failure mode in older designs.
  • ⚡ Optimized Efficiency: Advanced heat exchanger geometry maximizes heat transfer, reducing fuel consumption by 10-15%.

Where LiBr Dominates

  • 🏭 Waste Heat Recovery: Steel, Cement, Petrochem.
  • ♨️ Steam - Rich Plants: Textiles, Food Processing.
  • 🔥 Gas - Rich Areas: Replacing expensive grid power.
  • 🌱 Green Buildings: LEED/BREEAM certification.

Maintenance Reality

Contrary to myth, LiBr chillers are simpler than electric ones.

  • Electric Chillers: Compressors, motor windings, oil changes, vibration issues.
  • LiBr Chillers: Only one moving part (canned pump). No heavy vibration. Maintenance is primarily chemistry monitoring and tube cleaning.

⭐ Interested in Non - Electric Cooling ?

Whether you have waste heat or gas, BROAD has a LiBr solution for you.