A novel hybrid system coupled liquid dehumidification with absorption refrigeration driven by solar energy is proposed. Traditional and advanced exergy and exergoeconomic analyses of the system are conducted to ascertain the degree of irreversibility and potential improvement for each component. Based on the advanced exergy and exergoeconomic analyses, the effects of air humidity, segment temperature, and refrigeration temperature on the total exergy destruction and cost rates of the system are obtained. The total avoidable exergy destruction rate, avoidable exergy destruction cost rate, and avoidable investment cost rate of the system are selected as objective functions and optimized by using nondominated sort genetic algorithm-II. The results show that the total exergy destruction rate and the total exergy destruction cost rate reach 262.39 kW and 8.563 $/h, respectively. The generator and regenerator have higher cost rates of the irreversibility overall system, achieving the values 3.536 and 2.430 $/h, respectively. The absorber has the highest investment cost rate in the whole system. The endogenous parts of the exergy destruction and cost rates are much higher than the exogenous parts in the system. Multiobjective optimization results show that optimal values for the total avoidable exergy destruction rate and the exergy destruction cost rate are 50.99 kW and 1.60 $/h, which are 4.15 and 9.14% lower than those calculated by single-objective optimization, respectively. This study provides a potential way to utilize solar energy for dehumidification and refrigeration.

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Ammonia, as a bulk chemical, is widely used in fertilizers and fuels and is also a promising hydrogen carrier. Aiming at reducing the high energy consumption of the ammonia synthesis process, this study innovatively proposed a low-carbon ammonia synthesis process based on the cold energy utilization of liquified natural gas regasification. In this process, the cold energy released from the regasification of liquified natural gas was used as the refrigeration source of the air separation unit and carbon capture and storage unit, which improves the comprehensive energy utilization efficiency of the whole process of synthetic ammonia. Based on Aspen Plus simulations, the process economy and exergy were comprehensively analyzed. The total efficiency of the low-carbon ammonia synthesis process was 42.69%, of which the ammonia production capacity was 35.07 t/h, and the total capital investment of the integrated process was 3.4 × 10 7 USD, and the product cost was 387.86 USD. Compared with three different ammonia plants, the levelized cost of ammonia in the low-carbon ammonia synthesis process was reduced to 324.03 USD/ton. The proposed process can well solve the problems of high energy consumption in the ammonia synthesis process and provide a valuable production route for the low-carbon ammonia synthesis process.

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