US Patent 11161699 Solids conveying with multi-diameter piping circuit

A mixture of gas and solid particles are conveyed through a piping circuit connected between initial and terminal points. The gas is introduced at the initial point and the particles are introduced between the initial and terminal points. A diameter of the piping circuit increases downstream of where the particles are introduced, and a velocity of the gas is at least as great as a pick-up velocity of the particles at the point where the particles are introduced into the piping circuit. In addition to the above constraints, the piping circuit is sized so that total pressure losses due to flow in the piping circuit between the initial and terminal points are within a designated amount.