Separation system for polymeric blast media

摘要

A process and apparatus is described for recovering and cleaning for reuse a lightweight blast media typically a polymeric material that is employed as a gas and entrained abrasive for cleaning workpiece surfaces of dirt, corrosion scale, paint or the like. The process involves reentraining the contaminated abrasive material in a gas stream from the worksite. The entrained material was directed in to a separator which separates the abrasives and heavier contaminants from the gas stream by impinging onto a target. Heavier material cascades from the target into the separator collection zone while the lightweight contaminants are swept from the separation zone by means of a vacuum system. The contaminated abrasive media is further cleaned by separating blast media of acceptable size from oversize and finer contaminants, by means of triple screening. The blast media, subjected to a series of separators, achieves a finished product having a 3-5% contaminant content. The process and apparatus of the invention are particularly suitable for recovering polymeric blast media.