Frequent blockages in the hopper disrupt the feeding of coke to the furnace. This problem not only causes frustration to operators as they need to unblock the hopper manually but also affects recovery efficiency.
The analysis of the current hopper design demonstrated that the blockage problem is caused by the following factors,
- The chute outlet is too small for the coke particle size
- The fine coke particles are shifting and consolidating at chutes B and C.
- The hopper vibrator causes the fine powders to penetrate through the feed material and compact on top of the slide gate that is not in use.
- The flat areas at the bottom of the hopper support the build-up and further consolidation of these cohesive materials.
Fine materials (a) trajectories, (b) initial distribution and (c) final distribution
Proposed Design Change
A modified design is proposed for the hopper to improve the flow of materials:
- Increasing the outlets’ diameter from 200 to 250mm
- Introducing a smooth transition from rectangular to circular boundary
- Removing the vibrator
Schematic representation of the modified hopper
We used DEM simulation to validate the proposed design. The simulation of the proposed improved design shows the material flow increased by more than 400%, and the blockage problem was eliminated.