Dehydration Area & Core Technology Delivery Projects
Fluidized bed dryers boost production at high-altitude magnesium plant
Qinghai Salt Lake Industry Co., Ltd. (QSLIC) | China | 2010–2012
10-stage
fluid beds
30%
smaller vessels than predecessors
400°C
HCl gas
Challenge
- The existing fluid bed dryers needed to be reviewed for structural integrity and suitability at the new high-altitude project site, which was characterized by severe seismic zoning.
- The magnesium production-capacity target was 100,000 tpa, compared to the original production capacity of 48,000 tpa.
Solutions
- To achieve the higher production capacity, the number of fluidized bed dryers was tripled for a total of six hot air dryers and six HCl gas dryers.
- Finite element-analysis modeling was used to verify and improve the mechanical design of the fluidized bed dryers, reducing costs.
- The feed distribution to each dryer stage was enhanced for more uniform mixing, increasing dryer efficiency.
- The internal components of the dryers were simplified and optimized to increase their efficiency, achieve production targets, and reduce costs.
Highlights
- The new air dryer design has a 30% smaller vessel diameter.
- It uses the fluidized bed area and materials of construction more efficiently, and has improved the air duct layout and maintainability.
- The two existing HCl dryers were refurbished with minor changes to enhance cost savings.
- Fluid bed dryers were designed according to the ASME Boiler and Pressure Vessel Code Section VIII.
Project numbers
100,000 tpa magnesium production capacity2-stage hot-air fluidized bed dryer
10-stage HCl-gas fluidized bed dryer
2,700 m above sea level
400°C design temperature
