LOW SOLUBLE IRON CONTENT DIATOMITE FILTER AIDS

摘要

A process for manufacturing low soluble iron, medium flow rate diatomite filter aids and such filter aids are disclosed. Sodium aluminate is used as an additive. As compared to either straight calcined or soda ash flux-calcined diatomite filter aids of similar permeabilities made from the same ore, the disclosed filter aids have much lower iron solubilities. For instance, disclosed filter aids of about 0.3 to about 2.0 Darcy were made using an alkali aluminate as an additive/flux agent to have an EBC soluble iron content of less than 100 ppm versus more than 140 ppm for similar filter aids that were made from the same ore and flux-calcined with soda ash.