A Study Of The CCHP System Integrated With Low Temperature Flue Gas Heat Recovery And Ice Storage

To deep use of waste heat in low temperature flue gas CCHP system, and ease the CCHP system inefficiency due to varying condition caused by fluctuating cooling load in summer, the paper proposes a new CCHP system integrated with low-temperature flue gas heat recovery and storage device.The general form of the system as well as its core component, three tube device are given. Depending on the property of the heating exchange in three tube, the paper comes up with the heating exchange formulas separately in winter and summer, and further analysis the influence of the three tube size, the flow rate of the working fluid on outlet temperature. The result shows that, in older to meet the requirement of the working fluid outlet temperature, the inner tube diameter is not too big, the fluid should be in the turbulent state, the length of tube is as long as possible.ASPEN PLUS software is utilized to build a simulation model of the new system with the traditional CCHP system, and compare the two different systems. The simulation results show that, compared with traditional CCHP system, the new system will increase the production of domestic hot water system in winter from 14133 kg/h to 406511kg/h, the thermal efficiency increases from 71.51 to 82.46 percent, the exergy efficiency increases from 41.7% to 42.21 %; cold storage rate was 17.47%, the rate of cooling capacity upgrade(the ratio of three tube device maximum cooling capacity and chiller system cooling capacity) was 95.7%.Base on the simulation model, the paper further studies the effects of mixed flue gas temperature, flue gas flow rate, domestic hot water flow rate and the flow rate of refrigerant on the thermal performance of the system and cold storage and release properties. The result shows that the increasing temperature of mixed flue gases will reduce the system thermal efficiency, system storage rate and cooling capacity upgrade rate, and enhance the exergy efficiency of the system; the increasing flow rate of domestic hot watere will result in system thermal efficiency increasing and reduce exergy efficiency of the system. The increasing flow rate of refrigerant will lead to an increase in cooling capacity upgrade rate, and reduce cold storage time.