Method and apparatus for improving erosion resistance of the mixing

Abstract

To improve the erosion resistance of the mixing chamber of a jet pump employed to pump particulate containing fluids, this invention contemplates directing a pressurized source of clean fluid through an annular jet-type orifice, thus providing an annular jet of high velocity clean fluid at the inlet end of the mixing chamber which surrounds an orifice connected to the source of particulate containing fluid and effects the pressurizing and pumping of the particulate containing fluid by the well known jet diffusion technique. Additionally, this invention contemplates the provision of a second annular nozzle surrounding the first mentioned annular nozzle through which a relatively clean fluid is discharged, thereby interposing a clean fluid barrier between the momentumly transferred particulate containing fluid and the surface of the mixing chamber to protect such surface from the abrading effects of the particulate material. In a modification of the invention, the relatively particulate-free fluid stream is produced by diverting a portion of the pressurized clean fluid supplied to the jet pump to effect the centrifugal separation of the particulate containing fluid into two streams, respectively a radially inner stream relatively free of particulate which is supplied to the aforementioned outermost annular orifice and a central particulate rich stream which is supplied to the central orifice of the mixing chamber and educted therefrom by the annular high velocity jet stream of clean fluid.