Manufacture of microspheres using a hydrocyclone
AssigneeOakwood Laboratories, LLC
InventorsBagavathikanun Chithambara Thanoo, Edward Caldwell Smith, Mark Smith
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Abstract
This disclosure features a system for processing microspheres. A vessel contains a suspension of solidified microspheres comprising polymer and an active agent. A hydrocyclone has a fluid inlet, a first fluid outlet and a second fluid outlet. The fluid inlet is in fluid communication with the vessel and receives the suspension. The second fluid outlet contains a flow of the suspension having concentrated microspheres. The first fluid outlet contains a flow of a relatively large amount of liquid compared to the flow from the second fluid outlet. Also featured is a method of processing the microspheres using the hydrocyclone.
Claims19
A system for processing microspheres comprising:
- a vessel containing a suspension of solidified microspheres in a suspending medium comprising a solvent;
- a hydrocyclone (HC-1) having a fluid inlet, a first fluid outlet and a second fluid outlet, wherein said fluid inlet is in fluid communication with said vessel and receives said suspension, said second fluid outlet discharges a flow (flow A) of said suspension having an increased concentration of said microspheres relative to said suspension in said vessel, and said first fluid outlet discharges a flow (flow B) of said suspending medium having a lower concentration of said microspheres relative to said suspension in said vessel;
- and,
- a hollow fiber filter or a wet sieve having an inlet in fluid communication with said second fluid outlet,
- said system further comprising a second hydrocyclone (HC-2) having a fluid inlet, a first fluid outlet and a second fluid outlet, wherein said fluid inlet is in fluid communication with said first fluid outlet of hydrocyclone HC-1, said HC-2 second fluid outlet discharges a flow (flow C) of said suspension having an increased concentration of said microspheres relative to said flow B discharged from said first fluid outlet of hydrocyclone HC-1, and wherein said system combines said flow A from said HC-1 second fluid outlet and said flow C from said HC-2 second fluid outlet for fluid communication to said inlet of said hollow fiber filter or said wet sieve.
A method for processing microspheres comprising:
- forming a suspension of solidified microspheres in a suspending medium in a vessel;
- moving said suspension from said vessel to a fluid inlet of a hydrocyclone (HC-1), said HC-1 further having a first fluid outlet and a second fluid outlet;
- removing from said second fluid outlet a flow (flow A) of said suspension having an increased concentration of said microspheres relative to said suspension in said vessel;
- removing from said first fluid outlet a flow (flow B) of said suspension having a decreased concentration of microspheres relative to said suspension in said vessel;
- and,
- moving said flow A from said second fluid outlet to an inlet of a hollow fiber filter or wet sieve,
- and further comprising selecting one or both of an apex I.D. and an inlet flow rate of said HC-1 such that a 10% cumulative volume fraction (CVF) of said microspheres in said flow A from said second fluid outlet is increased relative to a 10% CVF of said microspheres in said suspension entering said HC-1 from said vessel.
Dependencies are inferred from the claim text.