Numerical Simulation of Catalytic Coal Hydrogasification in a Lab-Scale Pressurized Fluidized Bed
Fluidization
2019
Fluidization XVI
General Paper Pool
8D: Modeling and Simulation
Wednesday, May 29, 2019 - 5:01pm to 5:13pm
In this presentation, we conducted a TFM-KTGF simulation of catalytic hydrogasification in the lab-scale bed operated at 3.7umf. The predicted bed expansion height is validated with the empirical correlation. The average bubble size is found to be much smaller than the Mori-Wen correlation. As a key parameter, the bubble size distribution (BSD) is detected and statistically analyzed using a novel post-processing MATLAB code. The BSDs at different heights (0.25H, 0.50H, 0.75H, 1.0H) are shown to have a similar bimodal distribution. Furthermore, the bubbles are divided into three groups: the small (1 mm-3 mm), middle (3 mm-6 mm), and large (6 mm-9 mm) sized bubbles. The number of small bubbles decreases along the bed height, but the number of large bubbles increases. It is noted that the number of the middle sized bubbles is almost unchanged along the bed height. This suggests that the bubble coalescence and breakup tend to approach a balance. A catalytic hydrogasification model is coupled with the gas-solid hydrodynamics, and distributions of temperature and CH4 concentration were predicted and compared with the experimental results. Further work will be focused on the effects of bed height, bed diameter and particle size on the overall performance of the gasifier.