A Study of Gas Flow in a Slurry Bubble Column Reactor for the DME Direct Synthesis: Mathematical Modeling from Homogeneity vs. Heterogeneity Point of View

Document Type: Research Paper

Authors

1 Department of Chemical and Petroleum Engineering, Sharif University of Technology, Azadi Avenue, Tehran, Iran

2 Department of Chemical Engineering, Abadan Faculty of Petroleum Engineering, Petroleum University of Technology, Abadan, Iran

3 Chemical & Environmental Engineering Group, Graduate Faculty of Engineering, Islamic Azad University, South Tehran Branch. Tehran, Iran

Abstract

In the present study, a heterogeneous and homogeneous gas flow dispersion model for simulation and optimization of a large-scale catalytic slurry reactor for the direct synthesis of dimethyl ether (DME) from synthesis gas (syngas) and CO2, using a churn-turbulent regime was developed. In the heterogeneous flow model, the gas phase was distributed into two bubble phases including small and large while in the homogeneous one, the gas phase was distributed into only one large bubble phase. The results indicated that the heterogeneous gas flow model was in a better agreement with experimental pilot-plant data compared with that of the homogeneous one. Also, through investigating the heterogeneous gas flow for small bubbles as well as the large bubbles in the slurry phase (i.e.; including paraffins and the catalyst), the temperature profile along the reactor was obtained. The optimum value of rector diameter and height obtained at 3.2 and 20 meters respectively. The effects of operating variables on the axial catalyst distribution, DME productivity and CO conversion were also understudied in this research.

Keywords


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