Abstract: The combined trapezoid spray trays (CTST) are successfully applied in absorbers, desorbers and stabilizers in the FCCU of SINOPEC Zhanjiang Dongxing Petrochemical Co. Ltd. The revamping scheme was proposed based on computer simulation and the calculation of fluid dynamic performance. Switching the floating value trays to CTST without changing the supporting parts of the absorbers, desorbers and stabilizers in 1# FCCU and 2# FCCU were adopted. After revamping, the capacity of 1# and 2# FCCU is increased by 67% and 25%, respectively. In 1# FCCU stabilizer, the contents of C2 and C5 in LPG are less than 0.03%(v) and 0.02%(v), respectively. No C3 and C4 in the stabilized gasoline exist, and the saturated vapor pressure of stabilized gasoline is 63.65 kPa. In 2# FCCU stabilizer, the content of C2 is 0.03%(v) and C5 is 0.08%(v) in LPG, the stabilized gasoline has no C3 and C4, and the saturated vapor pressure of stabilized gasoline is less than 65 kPa. The contents of C3 in lean gas of 1# and 2# FCCU absorbers are 1.46%(v) and 0.95%(v), respectively. The contents of C2 in deethanized gasoline of 1# and 2# FCCU desorbers are 0.12%(v) and 0.03%(v), respectively.

Key words: absorber, desorber, stabilizer, modification, combined trapezoid spray tray