关键词: 干气制乙苯装置, 原料提纯, 设备腐蚀, 乙醇胺, 水, 丙烯, C₅⁺

Abstract: Dry gas to ethylbenzene process takes the dry gas from FCC unit as feedstock, which can effectively save resources and reduce the cost of ethylbenzene production. However, the biggest defect of the process is that there are many impurities in the dry gas, which increases the energy consumption in the process of dry gas purification and seriously corrodes the equipment, thus affecting the long-term operation of the unit. In this paper, by analyzing the influence of impurities such as H₂S, CO₂, ethanolamine, water, propylene and C⁺₅ components in dry gas on the unit, measures such as adding cyclone separator for dry gas, adopting high-throughput depropylene tray, purposefully replacing anti-corrosion equipment, reforming process flow and optimizing operation scheme are adopted. Then in the dry gas, ethylene volume fraction increases by 10.6%, propylene volume fraction decreases by 65.1%, propane volume fraction decreases by 50.0%, and the volume fraction of C⁺₃ component decreases by 54.4%. It can effectively increase the dry gas treatment capacity by 9,240 dam³/a, and save 55 kt of depropylene absorbent every year, effectively prevent the corrosion of H₂S, CO₂ to the equipment, and ensure the long-term operation of the unit.

Key words: dry gas to ethylbenzene unit, feedstock purification, equipment corrosion, ethanolamine, water, propylene, C₅⁺