关键词: 克劳斯系统, 堵塞, 二氧化硅, 酸性水, 外购原料油

Abstract: Blockage occurred frequently in Claus system of 10 kt/a sulfur recovery unit in the eastern region of CNOOC Taizhou Petrochemical Co., Ltd.. High switching frequency of Clause furnace severely affected the normal operation. It was found that the blockage was SiO₂, and acid gas from the sour water stripper was the main cause of the blockage. It was confirmed that the feedstock purchased outside for FCC unit was the final source of silicon. By strictly controlling the silicon content of the feedstock purchased outside, blending high-silicon and silicone-free feedstock, the silicon content of the feedstock reduced, and the silicon content in the sour water of the unit reduced from 540.0 μg/g to 0.5 μg/g. Thus the blockage of Claus system was obviously improved, and the switching frequency reduced greatly, from once every 12 days to once every 72 days. By optimizing the feedstock and purchasing less feedstock containing silicon, the blockage in Claus system of the unit was reduced, and the operation of the unit was stable.

Key words: Claus system, blockage, SiO₂, sour water, feedstock purchased outside