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S. Sangwan and P. R. Chakraborty
10.6 Heat Recovery Cycle
The schematic of two bed adsorption cooling system with heat recovery and associated thermodynamic cycle for the beds is shown in Fig. 10.2. At the completion of
each half of the cycle, desorption bed will be at highest temperature (T c ) and adsorption bed will be at lowest temperature (T a ). The bed at lowest temperature requires
heat to undergo desorption process while the bed at highest temperature needs to be
cooled, so that it can undergo adsorption process. Part of the heat rejected during
cooling (process c-d-a) can be utilized to preheat the desorbing bed (process a-b-c),
reducing the total amount of external heating and cooling requirements. It will also
result in the improvement of COP and second law efficiency of the system.
The heat recovery can be achieved by circulating a heat transfer fluid between
both the beds as shown in Fig. 10.3. But heat can only be recovered till both the beds
attains thermal equilibrium (point e and f in thermodynamic cycle).
Fig. 10.2 Schematic of two bed adsorption cooling system with heat recovery and associated
thermodynamic cycle for the beds