Design and optimization of LNG vaporization cold energy comprehensive utilization system based on a novel intermediate fluid vaporizer

In this paper, a novel type intermediate fluid vaporizer with LNG vaporization cold energy utilization was proposed and applied to 9200TEU container LNG power ship. Considering the different LNG vaporization parameters of the ship's main and auxiliary engines and the requirements of shipping for power generation, seawater desalination, cold storage and air conditioning, a comprehensive utilization system of LNG vaporization cold energy was constructed with a novel intermediate fluid vaporizer. Through the simulation and analysis of the scheme, and based on the cascade utilization of cold energy, the design scheme was optimized from the perspective of process arrangement and refrigerant selection. Finally, the parameter matching optimization of the determined optimization design scheme was carried out by using genetic algorithm. The results showed that the overall exergy efficiency of the optimal design scheme of the cold energy cascade utilization system of the ship LNG built in this paper based on the novel intermediate vaporizer was 51.09%, the net output electric power of the system was 342.228 kW, and the net profit of the system was about US $224,300 per year, and the cost was recovered in 7 years.