The C₂ hydrogenation reactor (R-401C/D) in the 220 kt/a ethylene plant of PetroChina Dushanzi Petrochemical Company was put into operation on November 8, 2022, and the ethylene increment at the reactor outlet was unstable during production. Product yield analysis software was used to extract production data every 4 hours to optimize the cracking depth and control the acetylene content at the reactor inlet. The EVA process of polymer grade ethylene was used to ensure that the flow rate of polymer grade ethylene was maintained at 26 t/h, so as to balance the cooling capacity of the system and control the overhead temperature of the deethanizer. The green oil in the first stage of reactor was removed regularly, and the amount of green oil entering the second stage bed was reduced, thus improving the activity of catalysts and the ethylene increment at the reactor outlet. In 2023, the average ethylene increment at the reactor outlet was 301 kg/h, with an average increase of 165 kg/h compared with that in the technical agreement.