优化碱洗塔操作控制裂解气压缩机段间凝液pH值

CONTROL OF PH VALUE OF INTERSTAGE CONDEN-SATE OF CRACKING GAS COMPRESSOR BY OPTIMI-ZING THE OPERATION OF CAUSTIC WASH TOWER

对独山子石化公司220 kt/a乙烯装置压缩单元碱洗塔(C-203)的操作进行优化,通过建立原料硫含量的监控机制、控制各段碱洗合理的浓度梯度、加注黄油抑制剂抑制黄油的产生、控制各碱液循环段的循环量以及设定合理的水洗段洗水量等措施,使弱碱室氢氧化钠的浓度(质量分数)保持在工艺指标0.2%~3.0%,避免了裂解气夹带碱液进入后系统,保证了裂解气压缩系统四段吸入罐(V-205)凝液pH值持续稳定控制在7.5~10.5,保障了压缩机组的“安稳长”运行。

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.