I apologise for the double post but I'm not sure whether a  mining or a civil guy is more likely to be able to help me. This is I believe a regular task in mining but very specialised for civil, and there is sopmething happening here way outside my area of mining expertise.

I'm presently having some major difficulties with segregation when dropping concrete down a vertical 500 metre slickline. Ive got some extremely comptetant people working on different mix designs and various additives but the question has been raised whether its possible to modify our concrte boot design, possibly to introduce compressed air as a remixer before we drop the concrete into the pump.  Anyone have experience with this or any other suggestions.??