Experimental Study Of Lithium Bromide Refrigeration Based On Mandatory Absorption Technology

After industrial process, redundant heat is released to the surrounding, which causes abundant waste and thermal pollution. The absorption refrigeration technology is widely applied for its characteristics of using environmentally friendly refrigerant and industrial waste heat. It is important to minimize the size of absorber and enhance heat/mass transfer for the further development of absorption refrigeration.Liquid-gas ejector is adopted for the purpose to strengthen heat transfer and mass transfer respectively. In order to improve mass transfer, absorber with liquid-gas ejector is used to investigate the effect of structure factors and environmental factors on cooling capacity.The results show that, for convergent-divergent nozzle and divergent nozzle, the increase in flow rate promotes the increase in cooling capacity. However, the mechanism is different for the influence of convergent-divergent nozzle and convergent nozzle on absorption effect. With the same minimum cross area, the cooling capacity with convergent-divergent nozzle is better than that with convergent nozzle. By adopting diffuser with small outlet diameter, the volume can be minimized without any influence on cooling capacity. Large difference between refrigerant vapor pressure and steam partial pressure of solution enhances absorption of water into aqueous lithium bromide solution. With convergent-divergent nozzle, the use of additive brings improvement in cooling capacity. The optimal concentration range of the solution is 56.61wt%～57.61wt%. Cooling capacity increases with the decreasing of back pressure.In conclusion, the following factors should be considered while making optimal design for absorber with liquid-gas ejector. The use of convergent-divergent nozzle, the diffuser with small outlet diameter decreases the volume of absorber. In addition, back pressure of diffuser should be reduced. Concentration of solution should be set in the range of optimal concentration. Moreover, the use of additive, pump with high flow rate and heat source with high temperature also improves cooling capacity.