关键词: 异构化装置, 排放气, 氢气, 膜分离, 重整氢, 干气制氢

Abstract: SINOPEC Tahe Petrochemical Co., Ltd. 300 kt/a hydro-isomerization unit adopts the process of hydrogen passing through at one time. The reaction tail gas is rich in hydrogen(about 70%), which is discharged into the fuel gas system after alkali washing tower, resulting in a large amount of waste of hydrogen source. Three feasible schemes for hydrogen recovery are proposed. Scheme 1: the tail gas enters the hydrogen purification unit of No.1 hydrogenation membrane separation unit and then is connected to the hydrogen pipe network of the whole plant. Scheme 2: the tail gas enters the No.2 hydrogen production unit as one of the feedstock for hydrogen production, the hydrogen with purity of 99.99% and pressure of 2.2 MPa is produced and put into the hydrogen pipe network. Scheme 3: the tail gas enters into the inlet of the booster of the continuous reforming unit and is connected to the hydrogen pipe network after boosting. Considering the operability and economic benefits, the best feasible scheme is scheme 2. It is estimated that the maximum benefit can be increased by 4.536 million yuan per year by using scheme 2 to recover hydrogen. It can provide a reference for the recovery of hydrogen source.

Key words: isomerization unit, exhaust gas, hydrogen, membrane separation, reforming hydrogen, hydrogen production from dry gas