High concentration red mud slurry versus dry filter cake

摘要

High Concentration Slurry Disposal (HCSD) technology is the generally accepted red mud disposal method.High concentration slurry can be obtained from paste thickeners or vacuum drum filters, but also by mixing dry filter cake from plate filters (pressure filters) with water.The attraction of using plate filters, instead of paste thickeners or vacuum drum filters is increased caustic soda recovery and hence reduced caustic soda transfer to the disposal area.HCSD pumps viscous red mud slurry to the disposal area where the slurry spreads by gravity and consolidates and compacts through surface evaporation.Disposal of dry filter cake requires mechanical spreading and compaction to obtain a self-draining sloped surface.Spreading and compaction requires equipment that cannot operate on the disposal area under heavy rain conditions, potentially interrupting mud disposal.The final moisture content and in-situ density that can be achieved by HCSD is equal to that of disposal of dry filter cake, provided that the storage area design provides for sufficient mud slurry drying and consolidation time.The difference between HCSD and disposal of dry filter cake disposal is that HCSD has more attractive economics and offers great operational advantages in the sense that it operates fully automatically and requires no mechanical equipment for discharging, compacting and spreading of solids on the disposal area.