武汉乙烯碳五分离装置开车过程分析

ANALYSIS ON THE STARTUP OF C_5 SEPARATION UNIT IN THE ETHYLENE PLANT IN WUHAN

武汉乙烯碳五分离装置以裂解汽油加氢装置副产的碳五馏分作为原料,利用各种烃类沸点的不同或在溶剂中相对挥发度相异而进行精馏、萃取精馏、共沸精馏,生产异戊二烯(聚合级)、间戊二烯和双环戊二烯、抽余碳五等产品,装置在首次开工过程中,出现了C5原料组成与设计指标相差甚远,因此在开车前需要进行原料精制,以达到能生产聚合级异戊二烯产品的条件。新建乙烯首次开工初期,可能有一个调整过程,首先要利用本装置工艺特点来处理这些不合格原料以达到本装置一次开车成功的目的。

The C5 separation unit in the ethylene plant in Wuhan takes the byproduct C5 fractions from pyrolysis gasoline hydrogenation unit as the raw material,and makes use of the different boiling points of hydrocarbons or different relative volatilities in solvents to produce isoprene( polymer-grade),pentadiene,dicyclopentadiene and raffinate C5 via distillation,extractive distillation and azeotropic distillation. During the first startup of the unit,the composition of C5 raw material deviated a lot from the design value,so raw material purification is needed before the startup to produce polymer-grade isoprene raw material. Some adjustment may be necessary in the early stage of the first startup of the new ethylene plant. The process features of the unit should be utilized to treat these off-spec raw materials,so as to achieve successful startup at the first try.