The necessity of C_3 hydrogenation unit existence in front depropanizer front hydrogenation flow of ethylene plant is studied and fully discussed.

This article analyzes main factors that affect the actual operation of Demethanizer, and discusses the problems existing in the Demethanizer after the revamp of ethylene plant in Fushun, CCPC.

Recent progress in world ethylene separation technology were reviewed and compared including sequence process, front-end deethanizer process, front-end depropanizer process.