Single-use spray drying components and methods of using the same
Spray drying method and systems are disclosed that include one or more single-use components. Single-use spray drying systems can include a drying chamber with an inner surface formed of a polymeric material. The single-use components can be pre-sterilized and sterile packaged to provide improved efficiencies and greater flexibility in spray drying systems.
1. A method of spray drying using a single-use drying chamber, comprising:
providing a gas inlet manifold comprising an inlet conduit that defines a gas passageway with a gas outlet and a spacing member that extends laterally from an exterior surface of the inlet conduit, wherein at least a portion of the inlet conduit extends into the single-use drying chamber so that the gas outlet of the inlet conduit is located within the single-use drying chamber;
securing the single-use drying chamber to the laterally-extending spacing member to establish a gap between an inner surface of an inlet end of the single-use drying chamber and an outside surface of the inlet conduit;
directing a spray liquid through a spray liquid passageway to an atomizer positioned adjacent the gas outlet, the spray liquid passageway including a proximal portion coupled to a spray liquid reservoir and a distal portion coupled to the atomizer;
forming a plurality of droplets using the atomizer and directing the plurality of droplets into the single-use drying chamber;
introducing a drying gas through the gas passageway and out the gas outlet into the single-use drying chamber to at least partially dry the plurality of droplets and form a plurality of spray-dried particles; and
directing the spray-dried particles out of an outlet of the single-use drying chamber,
wherein the single-use drying chamber has an inner surface comprising a polymeric material.
2. The method of claim 1 , wherein the spacing member extends sufficiently from an exterior surface of the inlet conduit to establish a circumferential gap between the inner surface of the inlet end of the single-use drying chamber to the outside surface of the inlet conduit of a length that is greater than 50% and less than 200% of a radius of the inlet conduit.
3. The method of claim 1 , wherein the spacing member extends sufficiently from an exterior surface of the inlet conduit to establish the circumferential gap between the inner surface of the inlet end of the single-use drying chamber to the outside surface of the inlet conduit of a length that is greater than 75% and less than 200% of a radius of the inlet conduit.
4. The method of claim 1 , wherein the spacing member extends sufficiently from an exterior surface of the inlet conduit to establish the circumferential gap between the inner surface of the inlet end of the single-use drying chamber to the outside surface of the inlet conduit of a length that is greater than 100% and less than 200% of a radius of inlet conduit.
5. The method of claim 1 , wherein the drying gas is introduced into the single-use drying chamber at a temperature greater than 100° C.
6. The method of claim 1 , wherein the drying gas is introduced into the single-use drying chamber at a temperature greater than 150° C.
7. The method of claim 1 , wherein the drying gas is introduced into the single-use drying chamber at a temperature greater than 200° C.
8. The method of claim 1 , wherein the polymeric material is a thermoplastic material.
9. The method of claim 1 , wherein the polymeric material is a flexible material and the introduction of the drying gas into the single-use drying chamber inflates the single-use drying chamber to define an enclosed volume.
10. The method of claim 1 , wherein the polymeric material forms an inner layer, the inner layer being at least partially surrounded by an outer layer, and
wherein the outer layer comprises a different material from the first layer.
11. The method of claim 1 , wherein the polymeric material has a melting point of 300° C. or less.
12. The method of claim 1 , further comprising performing one or more of the following steps:
sterile filtering the spray liquid before being directed to the atomizer;
sterile filtering the drying gas before being introduced into the single-use drying chamber; and
removing the single-use drying chamber from sterile packaging before securing the circumferential surface of the single-use drying chamber to the laterally-extending spacing member of the gas inlet manifold.
13. The method of claim 1 , wherein an outlet relative humidity of the spray-dried particles is less than 12%.
14. The method of claim 1 , wherein an outlet relative humidity of the spray-dried particles is between 2% and 10%.
15. The method of claim 1 , wherein a liquid to gas ratio during operation is between 0.015 and 0.03 on a mass basis.
16. The method of claim 1 , wherein the gas outlet of the inlet conduit extends between 2 and 6 inches into the drying chamber.
17. The method of claim 1 , wherein the gas outlet of the inlet conduit extends between 3 and 5 inches into the drying chamber.
18. The method of claim 1 , wherein the gas outlet of the inlet conduit extends between 3.5 and 4.5 inches into the drying chamber.
19. The method of claim 1 , wherein the spray liquid comprises an active pharmaceutical ingredient.
20. The method of claim 1 , wherein the spray liquid comprises a food or nutritional component.