Abstract: The operation of caustic wash tower (C-203) in the compression unit of the ethylene plant at PetroChina Dushanzi Petrochemical Company was optimized. By setting up a monitoring mechanism for sulfur content of raw material, controlling the reasonable concentration gradient of each caustic wash section, injecting polymer inhibitors to inhibit polymer generation, controlling the circulating amount of each caustic circulation section and setting a reasonable washing water amount for the water wash section, the sodium hydroxide concentration in weak caustic room was maintained within the technical index 0.2%~ 3.0%, the entrainment of caustic by cracking gas into the system was avoided, and the pH of condensate in the 4th-stage suction tank (V-205) of cracking gas compression system was continuously and stably controlled between 7.5 ~ 10.5, thus ensuring the safe, stable and long-term operation of the compressor unit.

Key words:  ')">

 , caustic wash tower, operation optimization, interstage condensate, pH