Patent ID: 9499443
Filing Date: 2016-11-22
CPC Classification: B01J,B04C,B05D,C04B,C09K,C10G,C10J

Claim Text:
1. A method for sintering green pellets to make proppant particles comprising the steps of: providing an apparatus comprising: a first cylindrical vessel having a first end, a second end and a first longitudinal axis, a first vortex finder connected to the first end of the first cylindrical vessel and aligned with the first longitudinal axis, a second cylindrical vessel having a third end, a fourth end and a second longitudinal axis, a second vortex finder connected to the second end of the first cylindrical vessel and aligned with the second longitudinal axis, an inlet passage disposed between the first vortex finder and the second vortex finder, connected tangentially to both the first cylindrical vessel proximate to the first end and the second cylindrical vessel proximate to the third end, and having an inlet and a third longitudinal axis, and a divider disposed within the inlet passage along the third longitudinal axis; supplying a heated gas to the inlet of the inlet passage; directing the heated gas into the first cylindrical vessel to form a first vortex gas flow and the second cylindrical vessel to form a second vortex gas flow using the divider; and dropping the green pellets into the first vortex finder or the second vortex finder or both the first vortex finder and the second vortex finder such that the green pellets are sintered or partially sintered in a selected temperature range to form the proppant particles as the green pellets pass through a first central portion of the first vortex gas flow and exit the second end of the first cylindrical vessel and/or pass through a second central portion of the second vortex flow and exit the fourth end of the second cylindrical vessel.