EO/EG装置对标启示及优化

Inspiration and Optimization of EO/EG Plant Benchmarking

镇海炼化EO/EG装置采用美国陶氏化学METEOR工艺专利技术及催化剂,从2010年首次开工运行至今获专利商多项运行纪录,但乙烯单耗、能耗等关键指标在全球范围内的竞争力并不清楚。经了解美国飞利浦汤森公司(PTAI)自2003年开始在全球范围内发起EO/EG装置的综合性能及成本竞争力的横向比较,全球已有100多套装置加入。为了解装置的综合竞争力,提高运行水平,2018年该装置加入了PTAI组织的装置绩效对标体系。由对标结果可知,装置催化剂运行性能较好,检维修费用低,但装置能源消费较高。通过增加DEG精制塔塔釜液进PGU精制塔流量、降低EO精制塔汽提甲烷用量、降低再吸收水流量等操作优化,提高了PGU精制塔侧线MEG收率、降低了中压蒸汽用量7.0 t/h,减少EO精制塔汽提甲烷用量约33 kg/h,提升了装置整体竞争力。

The ethylene oxide and ethylene glycol(EO/EG)plant of Zhenhai Refining&Chemical Company(ZRCC)adopts the patented process technology of Dow Chemical METEOR and its catalyst.The plant has been in operation since commissioning in 2010 and has obtained a number of operating records from the licenser.However,it is still not clear about the plant's competitiveness ranking worldwide in terms of ethylene unit consumption,energy consumption and other key indicators.The US-based Philip Townsend Associates Incorpration(PTAI)has initiated a horizontal comparison of the comprehensive performance and cost competitiveness for EO/EG plants worldwide since 2003,and more than 100 plants have joined the comparison system.In order to understand the overall competitiveness of the ZRCC EO/EG plant and improve its operation level,it joined the performance benchmarking system organized by PTAI in 2018.According to the benchmarking results,the plant has good catalyst performance,low maintenance costs,but high energy consumption.On the basis of the results,the plant improvement measures are identified.By increasing the flow rate of DEG refining tower bottom liquid into PGU refining tower,reducing the stripping methane of EO refining tower,and reducing the reabsorbed water flow,the EO/EG plant has increased the MEG yield of PGU refining tower sideline,reduced the consumption of medium-pressure steam by 7.0 t/h,and cut the consumption of stripping methane in EO refining tower by about 33 kg/h.These have improved the overall competitiveness of the EO/EG plant in ZRCC.