Method and apparatus for conveying solids using a high velocity vacuum

Abstract From the Canadian patent

A method and apparatus for pneumatically conveying solid materials such as soil, stones and the likeA hollow bored tube having an inlet end, a discharge end and an intermediate injector section is provided with at least one nozzle of the converging/diverging type within the injector section. A compressor supplies air at a pressure of about 90 psig to the nozzle to create an air stream within the tube directed toward the discharge end thereof, at a velocity in the supersonic regime. A strong vacuum is thus created in the region of the inlet end to provide rapid evacuation of the solids into the tube for conveyance therethrough and ejection at the discharge end thereof.