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S. Sangwan and P. R. Chakraborty
carbon–ethanol, silica gel–water, zeolite–water, metal hydrides–hydrogen, calcium chloride–ammonia and strontium chloride–ammonia etc. (Srivastava and
Eames 1998). Activated carbon–methanol has high adsorption and desorption
capacity with low heat of adsorption of the order of 1800–2000 kJ/kg. Desorption temperature cannot exceed 120
◦ C, because above this temperature methanol
will start decomposing. Activated carbon–ammonia with similar heat of adsorption as activated carbon–methanol pair, has the advantage of low evaporation
temperature of refrigerant and is used for high temperature heat source. Silica
gel–water is generally used for low temperature heat source because silica gel
will be destroyed at temperature higher than 120
◦ C. Zeolite–water has wide
range of desorption temperature from 70 to 250
◦ C and, the heat of adsorption is
around 3200–4200 kJ/kg, which is a disadvantage of this working pair. Activated
carbon–ethanol has the advantage of high adsorption/desorption capacity but has
low value of latent heat of vaporization approximately 30% lower than methanol.
It has saturation pressure similar to methanol. Activated carbon–ethanol works
best around desorption temperature of 100
◦ C.
B. Low grade heat utilization: Adsorption Refrigeration Technology is suitable for
recovery of thermal energy from low grade heat sources by using working pairs
such as Activated carbon–methanol. On the other hand, activated carbon–ammonia can be used for high temperature heat source. As compared to absorption
systems, adsorption refrigeration technology is more suitable in vibratory systems because of solid adsorbent. Therefore in the recent past, researchers focused
on the use of low grade heat in adsorption cooling.
Suzuki (1993) worked on zeolite–water based automobile air conditioner and
observed that heat and mass transfer properties of bed plays an important role
in minimizing the cycle time and mass of the system. Lavan (Mei et al. 1979)
worked out on the probability of a system that utilizes the exhaust gas of trucks.
Zhu et al. (1992) worked on the adsorption system used for fish storage on boats.
SJTU also developed some adsorption cooling systems (Wang et al. 2004; Wang
2001a) mainly activated carbon–ammonia based 5 kW air conditioner, zeolite–water based 5 kW system for locomotive cab and an ice maker based on
activated carbon–methanol.
Saha et al. (2007) studied an adsorption system based on activated carbon
fiber–ethanol which works on low temperature waste heat source (60–95 °C).
COP of the system is 0.6 with cycle time of 600–700 s.
C. Solar energy utilization: Solar energy based sorption cooling systems got attention due to the seasonal matching of cooling requirements and heat supply. Use of
low temperature heat as source of energy by adsorption cooling systems makes
them more suitable for solar energy applications as compared to absorption
systems.
Tchernev (Wang et al. 2014) developed a zeolite–water based adsorption cooling system, and from then onwards, researchers focused on the adsorption systems driven by solar energy. In France, Guilleminot and Pons (Grenier et al.
1988) investigated adsorption cooling systems which utilizes solar energy as heat
source, working pairs used were activated carbon–methanol and zeolite–water,
S. Sangwan and P. R. Chakraborty
carbon–ethanol, silica gel–water, zeolite–water, metal hydrides–hydrogen, calcium chloride–ammonia and strontium chloride–ammonia etc. (Srivastava and
Eames 1998). Activated carbon–methanol has high adsorption and desorption
capacity with low heat of adsorption of the order of 1800–2000 kJ/kg. Desorption temperature cannot exceed 120
◦ C, because above this temperature methanol
will start decomposing. Activated carbon–ammonia with similar heat of adsorption as activated carbon–methanol pair, has the advantage of low evaporation
temperature of refrigerant and is used for high temperature heat source. Silica
gel–water is generally used for low temperature heat source because silica gel
will be destroyed at temperature higher than 120
◦ C. Zeolite–water has wide
range of desorption temperature from 70 to 250
◦ C and, the heat of adsorption is
around 3200–4200 kJ/kg, which is a disadvantage of this working pair. Activated
carbon–ethanol has the advantage of high adsorption/desorption capacity but has
low value of latent heat of vaporization approximately 30% lower than methanol.
It has saturation pressure similar to methanol. Activated carbon–ethanol works
best around desorption temperature of 100
◦ C.
B. Low grade heat utilization: Adsorption Refrigeration Technology is suitable for
recovery of thermal energy from low grade heat sources by using working pairs
such as Activated carbon–methanol. On the other hand, activated carbon–ammonia can be used for high temperature heat source. As compared to absorption
systems, adsorption refrigeration technology is more suitable in vibratory systems because of solid adsorbent. Therefore in the recent past, researchers focused
on the use of low grade heat in adsorption cooling.
Suzuki (1993) worked on zeolite–water based automobile air conditioner and
observed that heat and mass transfer properties of bed plays an important role
in minimizing the cycle time and mass of the system. Lavan (Mei et al. 1979)
worked out on the probability of a system that utilizes the exhaust gas of trucks.
Zhu et al. (1992) worked on the adsorption system used for fish storage on boats.
SJTU also developed some adsorption cooling systems (Wang et al. 2004; Wang
2001a) mainly activated carbon–ammonia based 5 kW air conditioner, zeolite–water based 5 kW system for locomotive cab and an ice maker based on
activated carbon–methanol.
Saha et al. (2007) studied an adsorption system based on activated carbon
fiber–ethanol which works on low temperature waste heat source (60–95 °C).
COP of the system is 0.6 with cycle time of 600–700 s.
C. Solar energy utilization: Solar energy based sorption cooling systems got attention due to the seasonal matching of cooling requirements and heat supply. Use of
low temperature heat as source of energy by adsorption cooling systems makes
them more suitable for solar energy applications as compared to absorption
systems.
Tchernev (Wang et al. 2014) developed a zeolite–water based adsorption cooling system, and from then onwards, researchers focused on the adsorption systems driven by solar energy. In France, Guilleminot and Pons (Grenier et al.
1988) investigated adsorption cooling systems which utilizes solar energy as heat
source, working pairs used were activated carbon–methanol and zeolite–water,