LNG(液化天然气)高压供气系统主要应用于大型LNG动力船舶,其中MAN ME-GI二冲程低速机一直受制于国外技术。为了打破这一局面,对典型的LNG高压供气系统工艺进行分析梳理,提出了2种新型LNG高压供气系统工艺替代方案。通过实际案例分析比较,对LNG动力船舶在航行、装卸、加注、港口和锚地工况的BOG(蒸发气)气体量进行平衡计算,对比了不同LNG高压供气系统关键设备的规格,推荐BOG再液化装置采用Turbo-Brayton型、BOG/LNG管式混合器替代传统BOG/LNG换热器,优选出方案2作为国产化的LNG高压供气系统,为后续实船验证提供了工程基础。

LNG high pressure gas supply system is mainly applied in large-scale LNG powered ships for the MAN ME-GI two stroke low speed engine that is a technical barrier for China's companies.In order to solve this problem,two novel LNG high pressure gas supply system process alternatives are proposed through analyzing and sorting out the typical LNG high pressure gas supply system technologies.Through analyzing and comparing actual cases,the volume of boil off gas (BOG) of LNG powered ships is balanced during sea going,loading & offloading,bunkering,at port and anchorage conditions.Through comparing specifications of key equipment of different LNG high pressure gas supply system,it is suggested that Turbo-Brayton type is used as the BOG re-liquefaction unit,and BOG/LNG tube type mixer is used to replace the traditional BOG/LNG heat exchanger.Option 2 is selected as the localized LNG high pressure gas supply system in China,which provides an engineering basis for the follow-up actual ship verification.