摘要
针对某石化公司催化裂化轻汽油醚化装置加工方案调整过程中,醚化分馏塔再沸器低压蒸汽流量频繁波动的问题,从轻汽油组成、醚化反应转化率、醚化分馏塔塔内液相组成等方面进行原因分析。发现轻汽油中异戊烯浓度较低,醚化反应转化率较低,导致醚化分馏塔塔底甲基叔戊基醚(TAME)含量降低,进而破坏了醚化分馏塔塔内液相平衡。采取降低轻汽油侧抽出率及提高预反应器进料温度的措施,以控制轻汽油中异戊烯质量分数不小于9.07%及保证醚化预反应器内异戊烯转化率,进而提高了醚化分馏塔塔底TAME含量,消除了低压蒸汽波动现象。在低压蒸汽波动期间,含甲醇的醚化汽油送至甲醇回收单元,回收甲醇后,经C5抽余油线,送至成品罐,稳定了装置操作,提高了醚化汽油质量。
Based upon the frequent fluctuations of the low-pressure steam of CDEthers column reboiler in FCC light gasoline etherification unit, the root causes are analyzed in respect of light gasoline compositions, etherification conversion rate, liquid compositions in CDEthers column, etc. It is concluded that the main cau- ses are the lower content of isoamylene in light gasoline and lower etherification conversion rate, which lead to the reduced concentration of tert amyl methyl ether（TAME）in CDEthers column bottom and then destroy the liquid-phase equilibrium in CDEthers column. The operation is optimized by decreasing the side-draw rate of light gasoline and the inlet temperature of primary reactor etc, to control the mass fraction of isoamylene in light gasoline at no lower than 9.07% , ensure the conversion rate of isoamylene in primary reactor, increase the concentration of TAME in CDEthers column bottom and eliminate the low-pressure steam fluctuation. Dur- ing the low-pressure steam fluctuation, the etherified gasoline with methanol is sent to methanol recovery unit. The gasoline after methanol recovery is then sent to product tank via the C5 raffinate line. These have stabilized the unit operation and improved the quality of etherification gasoline.
出处
《炼油技术与工程》
CAS
2015年第4期44-47,共4页
Petroleum Refinery Engineering
