Modeling and optimization of industrial Fischer-Tropsch synthesis with the slurry bubble column reactor and iron-based catalyst

doi:10.1016/j.cjche.2018.01.002

摘要/Abstract

摘要： To optimize industrial Fischer-Tropsch (FT) synthesis with the slurry bubble column reactor (SBCR) and ironbased catalyst, a comprehensive process model for FT synthesis that includes a detailed SBCR model, gas liquid separation model, simplified CO₂ removal model and tail gas cycle model was developed. An effective iteration algorithm was proposed to solve this process model, and the model was validated by industrial demonstration experiments data (SBCR with 5.8 m diameter and 30 m height), with a maximum relative error < 10% for predicting the SBCR performances. Subsequently, the proposed model was adopted to optimize the industrial SBCR performances simultaneously considering process and reactor parameters variations. The results show that C₅₊ yield increases as catalyst loading increases within 10-70 ton and syngas H₂/CO value decreases within 1.3-1.6, but it doesn't increase obviously when the catalyst loading exceeds 45 ton (about 15 wt% concentration). Higher catalyst loading will result in higher difficulty for wax/catalyst separation and higher catalyst cost. Therefore, the catalyst loading (45 ton) is recommended for the industrial demonstration SBCR operation at syngas H₂/CO=1.3, and the C₅₊ yield is about 402 ton" per day, which has an about 16% increase than the industrial demonstration run result.

关键词: Fischer-Tropsch synthesis, Slurry bubble column reactor, Double bubble model, Process simulation and optimization

Abstract: To optimize industrial Fischer-Tropsch (FT) synthesis with the slurry bubble column reactor (SBCR) and ironbased catalyst, a comprehensive process model for FT synthesis that includes a detailed SBCR model, gas liquid separation model, simplified CO₂ removal model and tail gas cycle model was developed. An effective iteration algorithm was proposed to solve this process model, and the model was validated by industrial demonstration experiments data (SBCR with 5.8 m diameter and 30 m height), with a maximum relative error < 10% for predicting the SBCR performances. Subsequently, the proposed model was adopted to optimize the industrial SBCR performances simultaneously considering process and reactor parameters variations. The results show that C₅₊ yield increases as catalyst loading increases within 10-70 ton and syngas H₂/CO value decreases within 1.3-1.6, but it doesn't increase obviously when the catalyst loading exceeds 45 ton (about 15 wt% concentration). Higher catalyst loading will result in higher difficulty for wax/catalyst separation and higher catalyst cost. Therefore, the catalyst loading (45 ton) is recommended for the industrial demonstration SBCR operation at syngas H₂/CO=1.3, and the C₅₊ yield is about 402 ton" per day, which has an about 16% increase than the industrial demonstration run result.

Key words: Fischer-Tropsch synthesis, Slurry bubble column reactor, Double bubble model, Process simulation and optimization

Chufu Li. Modeling and optimization of industrial Fischer-Tropsch synthesis with the slurry bubble column reactor and iron-based catalyst[J]. Chinese Journal of Chemical Engineering, 2018, 26(5): 1102-1109.

Chufu Li. Modeling and optimization of industrial Fischer-Tropsch synthesis with the slurry bubble column reactor and iron-based catalyst[J]. Chin.J.Chem.Eng., 2018, 26(5): 1102-1109.

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