国内干气法乙苯脱氢制苯乙烯单位产品能耗分析及建议

Analysis on Energy Efficiency of Styrene from Dry Gas to Ethylbenzene Dehydrogenation in China

根据国内苯乙烯行业能耗计算标准长期不统一的现状,结合新发布的《苯乙烯单位产品能源消耗限额标准》(GB 32053—2015),对国内部分干气法乙苯脱氢制苯乙烯工艺相关装置的设计和实际运行能耗进行了对比,并对苯乙烯单位产品能耗进行了较为系统的分析和研究,结果表明:相关装置能耗均符合苯乙烯单位产品能源消耗限额要求。针对目前能耗计算标准不统一的现状,提出了计算苯乙烯单位产品能耗的方法,列出了能耗计算的范围和范例。另外,还针对不同苯乙烯生产装置能耗水平和存在差异化的主要原因进行了阐述,建议在GB 32053—2015基础上进一步完善能耗计算指标和方法,如对电能的能耗换算系数进行统一,增加各装置间能耗数值的可比性。

Wei-Jing Line needs heating throughout the year to transport Nanyang crude oil with high viscosity, high pour point and high density. After the heating furnace was modified with gas replacing oil as fuel, the gas furnace （oil/gas dual fuel） was used along the whole line, achieving good economic and social benefits. However, there were also problems such as unreasonable furnace structure and low-temperature corrosion. In order to solve the problems, the vacuum phase-change furnace was used for the first time in Wei-Jing Line. Instead of previous direct heating method, the vacuum phase-change furnace was designed to integrate with boiler and heat exchanger, use water as heat medium and exchange heat in vacuum chamber on the principle of vacuum phase-change, which improved efficiency and reduced boiler volume. Since put into use, the vacuum phase-change furnace has been running well as expected, helping reduce the maintenance and operating cost significantly.