Hydrogen sulfide removal by catalytic oxidative absorption method using rotating packed bed reactor

doi:10.1016/j.cjche.2016.08.032

Abstract

Abstract: Using catalytic oxidative absorption for H₂S removal is of great interest due to its distinct advantages. However, traditional scrubbing process faces a great limitation in the confined space. Therefore, there is an urgent demand to develop high-efficiency process intensification technology for such a system. In this article, H₂S absorption experimental research was conducted in a rotating packed bed (RPB) reactor with ferric chelate absorbent and a mixture of N₂ and H₂S, which was used to simulate natural gas. The effects of absorbent pH value, gas-liquid ratio, gravity level of RPB, absorption temperature and character of the packing on the desulfurization efficiency were investigated. The results showed that H₂S removal efficiency could reach above 99.6% under the most of the experimental condition and above 99.9% under the optimal condition. A long-time continuous experiment was conducted to investigate the stability of the whole process combining absorption and regeneration. The result showed that the process could well realize simultaneous desulfurization and absorbent regeneration, and the H₂S removal efficiency kept relatively stable in thewhole duration of 72 h. It can be clearly seen that high gravity technology desulfurization process,which is simple, high-efficiency, and space intensive, has a good prospect for industrial application of H₂S removal in confined space.

Key words: Confined space, RPB, Desulfurization, Catalytic oxidative, Absorption

摘要： Using catalytic oxidative absorption for H₂S removal is of great interest due to its distinct advantages. However, traditional scrubbing process faces a great limitation in the confined space. Therefore, there is an urgent demand to develop high-efficiency process intensification technology for such a system. In this article, H₂S absorption experimental research was conducted in a rotating packed bed (RPB) reactor with ferric chelate absorbent and a mixture of N₂ and H₂S, which was used to simulate natural gas. The effects of absorbent pH value, gas-liquid ratio, gravity level of RPB, absorption temperature and character of the packing on the desulfurization efficiency were investigated. The results showed that H₂S removal efficiency could reach above 99.6% under the most of the experimental condition and above 99.9% under the optimal condition. A long-time continuous experiment was conducted to investigate the stability of the whole process combining absorption and regeneration. The result showed that the process could well realize simultaneous desulfurization and absorbent regeneration, and the H₂S removal efficiency kept relatively stable in thewhole duration of 72 h. It can be clearly seen that high gravity technology desulfurization process,which is simple, high-efficiency, and space intensive, has a good prospect for industrial application of H₂S removal in confined space.

关键词: Confined space, RPB, Desulfurization, Catalytic oxidative, Absorption

Liangliang Zhang, Shuying Wu, Zuozhong Liang, Hong Zhao, Haikui Zou, Guangwen Chu. Hydrogen sulfide removal by catalytic oxidative absorption method using rotating packed bed reactor[J]. , 2017, 25(2): 175-179.

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