Taking geothermal heat as the heat source, KCS⁃11, KCS⁃34 and KSG⁃1 as the bottom cycles respectively, the thermodynamic and thermoeconomic performance of three systems combining flash⁃Kalina cycle and absorption refrigeration cycle (F⁃KCS11⁃ARC, F⁃KCS34⁃ARC, F⁃KSG1⁃ARC) were compared and analyzed. The results show that the total exergy loss of the F⁃KCS11⁃ARC system is 5.3% and 2.7% lower than that of the F⁃KCS34⁃ARC system and the F⁃KSG1⁃ARC system,respectively,and the component with the largest exergy loss is the heat exchanger 1. The F⁃KCS34⁃ARC system has the highest thermal efficiency, but the F⁃KCS11⁃ARC system has the highest heat recovery efficiency when the geothermal source temperature is in the range of 155～220 °C, and the smaller geothermal source temperature and flash pressure can make the system obtain higher heat recovery efficiency.Thermal economic analysis shows that pump 1 is the most expensive component in all three systems, the next is steam turbine 2. The F⁃KCS11⁃ARC system has the lowest cost, the highest annual net income, and the smallest investment recovery period, with values of 2.09×106 $, 6.61×105 $ and 3.72 years, respectively.

With the rapid advancement of ecological civilization construction in China, energy utilization methods such as recycling industrial waste heat and developing clean energy have gradually received widespread attention in the market. In this paper, a dual⁃loop cycle⁃kalina (DORC⁃KC) cogeneration system based on LNG cold energy utilization was designed. In addition, a new method for reducing acid gas emissions from industrial waste heat was proposed. Through the construction of the system thermodynamic model, the key thermodynamic parameters affecting the system carbon capture were analyzed in detail. The results show that the top cycle in the double cycle uses cyclopentane as the working fluid. By increasing the evaporation temperature and evaporation pressure, the maximum net output of the system is 367.9 kW,and the thermal efficiency is 33.29%. In the Kalina cycle, factors such as flux and concentration have a positive impact on system efficiency. The optimal thermal efficiency is 15.42% and the cold energy recovery efficiency is 20.65%. The reduction in compression pressure reduces the amount of circulating water but increase the quantity of the liquefaction of CO2. When the compression pressure is 472 kPa, the system has the highest exergy efficiency of 34.30%, carbon capture rate of 47.00%, and the amount of recycled water recovered is 167 616 t.