What is claimed is:
1. A piping circuit for conveying particles comprising:
a first segment comprising an intersection where particles dispersed in a first gas combine with a second gas form a mixture, a cross sectional area inside the first segment strategically sized so that when the mixture flows through the first segment the particles are at a velocity at least as great as a pick up velocity of the particles, the intersection comprising a junction where a first pipe carrying the first gas and the particles joins directly with a second pipe carrying the second gas so that the first gas and particles are introduced directly into a flow of the second gas within the second pipe; and
a second segment comprising an upstream end in communication with the first segment, a terminal end distal from the upstream end, and a cross sectional area greater than the cross sectional area of the first segment and strategically sized so that when the mixture flows through the second segment the particles are at a velocity at least as great as a saltation velocity of the particles.
2. The piping circuit of claim 1 , wherein the second segment is strategically positioned a length L from the intersection to limit pressure losses of the mixture and so that the mixture retains sufficient kinetic energy to reach the terminal location at a velocity above the saltation velocity.
3. The piping circuit of claim 1 , wherein the intersection is in communication with a discharge line from a process vessel, and where in the process vessel comprises the source of the particles.
4. The piping circuit of claim 3 , wherein the process vessel comprises a second gas that flows with the particles to the intersection.
5. The piping circuit of claim 1 , wherein pressures at the intersection and at the terminal end are fixed, and a flow rate of the gas and particles are fixed, and wherein the cross sectional areas of the first and second segments are sized so that a pressure drop in the first and second segments is no greater than a difference in pressure between fixed pressures.
6. The piping circuit of claim 1 , wherein the terminal end is at an elevation greater than the junction.
7. The piping circuit of claim 1 , further comprising a particle source, and wherein the particles are stored within the particle source, and wherein the particles are selectively conveyed from the particle source to the first segment through a line that connects between the particle source and the first segment.
8. The piping circuit of claim 1 , wherein the second segment is spaced a distance downstream of the intersection so that the particles P are traveling in the second segment at substantially the same velocity as carrier gas in the mixture.