25000 t LNG燃料动力化学品船能量利用系统的设计及优化分析

以25000 t LNG燃料动力化学品船为研究对象，在分析及评估原船废气余热利用系统以及高温冷却水系统用能水平基础上，针对船舶发电、海水淡化、冷库及空调等需求，综合考虑原船余热资源及未加以利用的LNG冷能，以加装废气动力涡轮、LNG冷能ORC发电、冷冻法海水淡化及设置高低温冷库与空调系统等方式组合提出了五种能量系统梯级利用方案。通过HYSYS软件模拟计算和对比分析，从（火用）效率及经济性两个方面对各方案进行了评估。结果表明，诸方案中以低温冷库+高温冷库+空调系统经济性最好，所形成的新设计系统经优化后（火用）效率可提高至62.87%，每年经济收益可达1227.85万元。

Simulation and optimization of energy utilization system of 25000 tons of LNG powered chemical tanker

25000 tons of liquefied natural gas (LNG) powered chemical tanker was studied. After analysis of the original ship exhaust gas system and high temperature cooling water system, considering the residual heat resources of the original ship and the unused LNG cold energy, combinations such as exhaust power turbine, LNG cold energy generation ORC, freezing water desalination,high and low temperature cold storage and air-conditioning systems were installed to meet the demand of power generation, desalination, cold storage and air-conditioning in this ship. Also, five kinds of energy system cascade utilization schemes of LNG cold energy were put forward. Through the simulation calculation and comparative analysis of software HYSYS, aspects of exergy efficiency and economy of each scheme were evaluated. The result showed that low temperature cold storage + high temperature cold storage + air conditioning system was the best in economy and exergy efficiency. The exergy efficiency of new system can be improved to 62.87% after optimization. At the same time, the annual economic income can reach 12.2785 million CNY.