Aerated surfactant soln. for flushing filter beds - using polymeric electrolytes to emulsify residual oil and grease

摘要

High-mol. wt. cationic polyelectrolytes are added to water for cleaning filters contaminated with oil. The water is aerated by air injection as it enters the filter. The process is used for removing residual oils or greases from filter beds of gravel, fine sand, etc. esp. for recovery and re-use of industrial cooling or wash liquors. The flotation/emulsification effects of using an aerated surfactant soln. followed by a water rinse reduces the total vol. of water reqd. for cleaning a filter by a factor of 1/2 to 1/4. The emulsified oil, etc. settles rapidly (20m/h) from the aq. layer, allowing the latter to be re-used merely by making up the electrolyte content.