It’s common to have the need for more than a single cooling demand, often different temperature levels and various refrigeration capacities are necessary.

For example, a split of absorption plant in two stages of absorption / evaporation permits you to generate two separate temperature levels and two refrigeration capacities. The solution leaving the low temperature absorber (2a) has an intermediate concentration and is capable of absorbing more ammonia vapor in the high temperature absorber (2b). In this way the overall efficiency is improved.