Industrial centrifuge with sealed bearings for chemical extraction

Abstract

An industrial centrifuge (10) for extracting one or more compounds from biomass includes a centrifuge basket (100) disposed within a cylindrical vessel (20). The centrifuge basket (100) includes a cylindrical sidewall having an upper perforated portion (320) and a lower solid portion (330), and a basket base plate (350) connected to the sidewall between the upper perforated portion and the lower solid portion. The centrifuge includes a spindle (70) connected to the basket base plate (350), a spindle bearing assembly (420), and a contact seal (440) disposed between the spindle bearing assembly and the basket base plate. The lower solid portion of the sidewall, the spindle, and the basket base plate define an enclosed volume (354). During operation of the industrial centrifuge, the air trapped within the enclosed volume provides an air seal between the extraction fluid in the cylindrical vessel and the contact seal, the spindle bearing assembly, or both, preventing the extraction fluid from contacting and damaging the spindle bearing.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 046,787, filed July 1, 2020, entitled “Air Sealed Bearing for an Industrial Centrifuge for Chemical Extraction,” the contents of which are relied upon in their entirety and incorporated by reference herein. [Technical field]

[0002] The present disclosure relates to industrial centrifuges, and more particularly to industrial centrifuges used in chemical extraction processes. [Background technology]

[0003] Industrial centrifuges may be used to extract one or more chemicals from a mixture of botanical (plant) material. In one application for extracting botanical products, industrial centrifuges may be used to cryochemically extract cannabidiol (CBD) oil droplets from biomass, including industrial hemp or certain low-THC varieties of marijuana. Typically, cryochemical extraction is performed at low temperatures, such as about -40°F (about -40°C), in the presence of an extraction fluid. The extraction fluid extracts the CBD oil droplets, which are carried by the extraction fluid and separated from the biomass by centrifugal forces. Summary of the Invention [Problem to be solved by the invention]

[0004] Various bearings in industrial centrifuges are exposed to extraction fluids, which can cause damage to the bearings or motor of the industrial centrifuge. The present disclosure relates to an air seal in an industrial centrifuge spindle bearing assembly to prevent leakage of extraction fluid into the spindle bearing assembly, the motor bearing assembly, or both. Reducing or preventing exposure of the bearing assembly to the extraction fluid can reduce or prevent damage to the spindle bearing assembly, the motor bearing assembly, the motor, or a combination thereof. Additionally, the air seal can allow for a cost-effective alternative to sealed bearings constructed from materials that can be used for extraction centrifuge operation with cooling extraction fluids at -40°F (approximately -40°C). The air seal can be passive and driven only by the gravity of the extraction fluid compressing the air trapped in the chamber housing the bearing assembly. [Means for solving the problem]

[0005] In one or more embodiments of the present disclosure, a centrifuge basket of an industrial centrifuge for extracting compounds from biomass may include a sidewall including an upper perforated portion and a lower solid portion, the sidewall being cylindrical and the lower solid portion being free of perforations. The centrifuge basket may further include a basket base plate coupled to an inner surface of the sidewall between the upper perforated portion and the lower solid portion. The centrifuge basket may further include a spindle mounting assembly coupled to the basket base plate. The lower solid portion of the sidewall, a lowermost surface of the basket base plate, and a housing of the spindle mounting assembly may define an enclosed volume operable to form an air seal between an extraction fluid and one or more bearings during operation of the industrial centrifuge.

[0006] In one or more other embodiments of the present disclosure, an industrial centrifuge for extracting one or more compounds from biomass may include a centrifuge basket disposed within a cylindrical vessel. The centrifuge basket may include a cylindrical sidewall and may include an upper perforated portion and a lower solid portion. The centrifuge basket may further include a basket base plate coupled to an inner surface of the sidewall between the upper perforated portion and the lower solid portion. The industrial centrifuge may include a spindle coupled to the basket base plate and operably coupled to a drive mechanism operable to rotate the spindle about an axis. The industrial centrifuge may further include a spindle bearing assembly coupled to the cylindrical vessel and disposed between a bottom of the cylindrical vessel and the basket base plate. The industrial centrifuge may further include a contact seal disposed between the spindle bearing assembly and the basket base plate. The spindle may extend vertically downward through the spindle bearing assembly to a drive mechanism disposed vertically below the bottom of the cylindrical vessel. The lower solid portion of the sidewall, the basket base plate, and a portion of the spindle may define an enclosed volume, and at least a portion of the spindle bearing assembly may be disposed within the enclosed volume. During operation of the industrial centrifuge, air trapped within the enclosed volume may provide an air seal between the extraction fluid of the tub and the contact seal. The air seal may reduce or prevent contact of the contact seal and a portion of the spindle bearing assembly with the extraction fluid contained in the tub during operation.

[0007] In one or more other embodiments of the present disclosure, the vertical chemical extraction centrifuge may include a motor drive control, an operator control and safety system, and a leak-proof cylindrical vessel housing a cylindrical centrifugation basket. The centrifugation basket may include a cylindrical basket having a partially perforated basket wall region that may extend above a sealed peripheral attachment to a solid centrifugation basket base plate. The centrifugation basket may further include a basket wall region that extends below the basket base plate, forming a solid cylindrical enclosure that extends below the centrifugation basket base plate. The centrifugation basket base plate may be mounted to a rotating vertical spindle that extends below the base plate. The industrial centrifuge may include a spindle bearing assembly mounted to the cylindrical vessel. The rotating vertical spindle may rest on a spindle bearing assembly that is connected to the motor drive through a leak-proof cylindrical vessel. The solid cylindrical enclosure extension may extend vertically below the spindle bearing assembly. When the vessel is filled with the extraction fluid, an air bubble may form in the enclosed extension area below the basket base plate, which may act as an air seal for the spindle bearing assembly, protecting it from exposure to the extraction fluid.

[0008] The following detailed description of specific embodiments of the present disclosure can be best understood when read in conjunction with the accompanying drawings, in which like structure is indicated with like reference numerals and in which: [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic perspective view of an industrial extraction centrifuge according to one or more embodiments shown and described herein. [Diagram 2] FIG. 1 is a cross-sectional schematic diagram of an industrial extraction centrifuge according to one or more embodiments shown and described herein. [Diagram 3]FIG. 2 is a cross-sectional view that illustrates a schematic of a centrifuge basket of the industrial extraction centrifuge of FIG. 1 according to one or more embodiments shown and described herein, the centrifuge basket including a spindle mounting assembly coupled to a basket base plate. [Figure 4] FIG. 4 is a schematic cross-sectional view of a portion of the centrifuge basket of FIG. 3 according to one or more embodiments shown and described herein. [Diagram 5] FIG. 4 is a schematic bottom view of the centrifuge basket of FIG. 3 according to one or more embodiments shown and described herein. [Figure 6] FIG. 4 is a schematic cross-sectional view of the industrial centrifuge of FIG. 1 having the basket spindle bearing assembly of FIG. 3 according to one or more embodiments shown and described herein, with the spindle bearing air seal in operation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The present application relates to methods and seals for reducing or preventing bearing damage in industrial centrifuges caused by exposure of the spindle bearing, motor bearing, or both to extraction fluids. In particular, the present disclosure relates to industrial centrifuges having a centrifuge basket and spindle bearing assembly that creates an air seal that can prevent exposure of the spindle bearing, motor bearing, or both to extraction fluids, thereby reducing the risk of damage to the spindle bearing, motor bearing, or both.

[0011] Sealing bearings such as rotating shaft ball and roller bearings from wet environments can be a challenge. Ball bearings can be distinguished into three different types: open bearings (with exposed balls and ball races), shielded bearings, and sealed bearings. Open bearings, such as open ball bearings, are the most cost-effective bearings, and with exposed ball bearings and ball races, fluids, solid debris, or both may come into contact with the balls and ball races. In the case of open bearings in industrial extraction centrifuges, the balls and ball races are not protected from exposure to the extraction fluid, which can result in damage to the balls and ball races.

[0012] Shielded bearings may include one or more shields that protect the balls and ball races. The shields are metal disks that connect to the outer bearing race, and the shield bore does not contact the bearing inner race. Shielded bearings may prevent solid particles and some liquids from entering the bearing, but they do not completely prevent liquids from reaching the balls and ball races.

[0013] A sealed bearing may include one or more fluid seals that may be constructed from various elastomeric materials and may be in contact with the shaft itself. The type of fluid seal material may be selected based on compatibility with environmental factors such as the fluid composition, viscosity, temperature, and hydraulic pressure of the fluid. Mechanical factors such as whether the shaft slides (in the case of a hydraulic cylinder) or rotates (in the case of a pump or centrifuge) as well as the shaft surface speed may also influence the choice of seal type.

[0014] Companies such as AW Chesterton of Groveland, Massachusetts specialize in rotating shaft seals that are widely used in pumps and valves. Shaft seals vary from simple elastomeric lip seals to complex rotating face seal assemblies. Seals that can be used in extractive centrifuges that operate with extraction fluids such as alcohol or aliphatic solvents cooled to -40°F are complex. The main technical challenge is to find an elastomer that is elastic at -40°F and will not degrade when exposed to organic solvents such as, but not limited to, ethanol, heptane, or other extraction fluids. Thus, a functional motor bearing seal assembly for an industrial centrifuge that can be used in contact with extraction fluids such as ethanol or heptane cooled to -40°F can cost thousands of dollars.

[0015] The present disclosure relates to air seals for the spindle bearing, motor bearing, or both, of a spindle bearing assembly of an industrial centrifuge performing low temperature solvent extraction. The air seals of the present disclosure may prevent contact between the rotating spindle, motor, and / or hydrostatic spindle bearing seals and the extraction fluid, which may be ethanol or heptane at -40°F (approximately -40°C) in a chemical extraction centrifuge. Additionally, other extraction fluids suitable for low temperature extraction are also contemplated.

[0016] The air seal is created by forming an air bubble disposed between the sealing surface and the extraction fluid interface. The air bubble may be formed below the centrifuge base plate as described further in this disclosure. In particular, the centrifuge base plate and the lower solid portion of the side wall of the centrifuge basket may define an enclosed volume that is airtight. The spindle bearing of the rotating spindle that supports the centrifuge basket may be arranged to always be located within the air bubble formed in the enclosed volume defined below the centrifuge base plate. Only the air in the air bubble contacts the spindle bearing, the motor bearing, or both. Thus, the air in the air bubble separates the spindle bearing, the motor bearing, or both from the extraction fluid. The air seal may allow the use of simpler commercially available rotating non-fluid-tight bearing seals, such as lip or face seals. These standard seals are a fraction of the cost of custom-made fluid-tight bearing seal assemblies that can be used in contact with pure ethanol or heptane extraction fluids at -40°F (approximately -40°C).

[0017] 1 and 2 show an industrial centrifuge 10 for chemical extraction of the present disclosure. An example of an industrial centrifuge 10 for chemical extraction may be a Western States Machine Company Model C40 Botanical Extraction Centrifuge designed and manufactured for OEM sales, but is not intended to be limited thereto. With reference to FIG. 1, the industrial centrifuge 10 includes a cylindrical vessel 20, which may be referred to as a kerb. The cylindrical vessel 20 may be coupled to a machine bed 30. The machine bed 30 may form the bottom of the cylindrical vessel 20. In an embodiment, the cylindrical vessel 20 may have a separate kerb base plate 430 (FIG. 6) coupled to the cylindrical vessel 20, which in turn is coupled to the machine bed 30. With reference to FIG. 2, the industrial centrifuge 10 may include a control panel 40 that may be communicatively coupled to a motor 60. With reference to FIG. 2, the cylindrical vessel 20 or the kerb may include a lid 412 that is removable from and sealable to the cylindrical vessel 20. The lid 412 may be removed to add biomaterial to the industrial centrifuge 10. The lid 412 may include one or more input pipes 470 that allow extraction fluid or other materials to be introduced into the vessel 20. The vessel 20 may further include one or more output pipes 480 that remove the extraction fluid and extracted materials from the vessel 20.

[0018] Referring again to FIG. 2, the industrial centrifuge 10 includes a centrifuge basket 100 disposed within the cylindrical vessel 20. The centrifuge basket 100 may be a rotating cylindrical centrifuge basket in which chemical extraction is performed from the rotating biomass. The centrifuge basket 100 may be rotatable relative to the cylindrical vessel 20. The centrifuge basket 100 may be fixedly connected to a spindle 70. The centrifuge basket 100 may be driven by the spindle 70, which may be connected by a timing belt 80 to an electric motor 60 disposed under the stepped machine platform 30. Although shown as having a timing belt 80, it is understood that the electric motor 60 may be operably connected to the spindle 70 through other types of connections. The industrial centrifuge 10 may include a control panel 40 for operating the centrifuge 10, and an emergency stop button 50, both of which are located at the top right of FIGS. 1 and 2. The industrial centrifuge 10 may further include casters 90 for easily moving the industrial centrifuge 10 between different locations.

[0019] Referring now to FIG. 3, a cross-sectional view is shown, which is a schematic representation of one embodiment of the centrifuge basket 100. The centrifuge basket 100 may include a sidewall 310, a stiffening ring 340 coupled to the top of the sidewall 310, and a basket base plate 350. The centrifuge basket 100 may further include a spindle mounting assembly 380 coupled to the basket base plate 350 of the centrifuge basket 100. The sidewall 310 may be cylindrical and vertical such that the central axis A of the cylindrical sidewall 310 is parallel to the + / -Z direction of the coordinate axis of FIG. 3. The sidewall 310 may include an upper perforated portion 320 and a lower solid portion 330. The upper perforated portion 320 may include a plurality of perforations 314 spaced apart across the upper perforated portion 320. The lower solid portion 330 of the sidewall 310 may be free of perforations. The upper perforated portion 320 and the lower solid portion 330 of the centrifuge basket sidewall 310 may be separated by a horizontal plane P (e.g., a plane perpendicular to the + / -Z direction of the coordinate axes of FIG. 3) that is tangent to the bottom of the perforations 314 of the bottom row 316. The bottom row 316 of perforations 314 is a horizontal row of perforations 314 around the periphery of the centrifuge basket 100 and may have a lower vertical position (e.g., a position in the + / -Z direction of the coordinate axes of FIG. 3) than any other row of perforations 314 (e.g., located in the -Z direction from all other perforations 314).

[0020] The sidewall 310 of the centrifuge basket 100 may be formed by perforating a portion of a flat metal sheet to produce an upper perforated portion 320. The partially perforated flat metal sheet may then be rolled into a cylindrical shape and the ends of the partially perforated metal sheet may be welded together along a seam 315 to produce the sidewall 310 of the centrifuge basket 100 having a cylindrical shape. The top edge of the sidewall 310 may then be welded to an edge of a stiffening ring 340.

[0021] Further, the centrifuge basket 100 may include a basket base plate 350, which may be a disk-shaped plate. The basket base plate 350 may be connected / welded to the side wall 310 between the upper perforated portion 320 and the lower solid portion 330 of the side wall 310. The basket base plate 350 may be oriented horizontally such that a center plane C of the basket base plate 350 is perpendicular to the + / -Z direction of the coordinate axis of FIG. 3. The basket base plate 350 may have a lowermost surface 352 and an outer radial edge 356. The basket base plate 350 may be coupled to the side wall 310 such that the outer radial edge 356 of the basket base plate 350 is connected to the inner surface 312 of the side wall 310.

[0022] 3, the basket base plate 350 may be positioned within the cylindrical sidewall 310 between the upper perforated portion 320 and the lower solid portion 330 of the sidewall 310, such as just below the bottom of the upper perforated portion 320 of the sidewall 310, such that the perforations in the sidewall 310 are not below the height of the basket base plate 350. Now referring to FIG. 4, the basket base plate 350 may be positioned relative to the sidewall 310 such that a center plane C of the basket base plate 350 is located vertically below (e.g., in the −Z direction of the coordinate axis of FIG. 4) a horizontal plane P tangent to the bottom of the perforations 314 in the bottom row 316. The basket base plate 350 may be positioned relative to the sidewall 310 such that at least a portion of the lower solid portion 330 of the sidewall 310 extends below the basket base plate 350. In an embodiment, the basket base plate 350 may be positioned relative to the sidewall 310 such that a central plane C of the basket base plate 350 is located vertically above (e.g., in the +Z direction of the coordinate system of FIG. 4 ) the bottom end 332 of the sidewall 310. In an embodiment, the basket base plate 350 may be positioned relative to the sidewall 310 such that a bottom surface 352 of the basket base plate 350 is located vertically above (e.g., in the +Z direction of the coordinate system of FIG. 4 ) and spaced apart from) the bottom end 332 of the sidewall 310. The lower solid portion 330 of the sidewall 310 that extends below the basket base plate 350 may be free of any perforations or holes. 5, a disk-shaped basket base plate 350 may be coupled / welded to the inner surface 312 of the sidewall 310 along an inner cylindrical circumference 360 ​​between the upper perforated portion 320 and the lower solid portion 330 of the sidewall 310.

[0023] The basket base plate 350 may be coupled to the inner surface of the side wall 310 in a manner that prevents extraction fluid from entering between the basket base plate 350 and the inner surface of the side wall 310. The basket base plate 350 may be coupled, such as by welding, to the side wall 310 such that the basket base plate 350 is sealed to the side wall 310 and liquid or gas cannot pass through the joint between the basket base plate 350 and the side wall 310. The joint coupling the basket base plate 350 to the side wall 310 may be airtight because the basket base plate 350 and the lower solid portion 330 of the side wall 310 form an air bubble through which air cannot escape or extraction fluid cannot enter the air bubble.

[0024] 3, basket base plate 350 may comprise the sealed basket bottom of centrifuge basket 100. Basket base plate 350 may be a solid circular plate having a top surface 351 and a bottom surface 352. Basket base plate 350 may have a hole in the center that receives spindle mount assembly 380. Sealed spindle mount assembly 380 may be welded to basket base plate 350. In an embodiment, spindle mount assembly 380 may be disposed in the hole in basket base plate 350 and welded or otherwise coupled thereto.

[0025] The spindle mount assembly 380 may include a housing 382 and a solid cover 390. As previously indicated herein, the basket base plate 350 may have a central opening, and the housing 382 of the spindle mount assembly 380 may be disposed within the opening and coupled to the basket base plate 350. In an embodiment, the basket base plate 350 may be welded to the housing 382 of the spindle mount assembly 380 with one or more welds 370. The spindle mount assembly 380 may be coupled to the basket base plate 350 to prevent extraction fluid from entering between the basket base plate 350 and the spindle mount assembly 380. The basket base plate 350 may be coupled, such as by welding, to the spindle mount assembly 380 such that the basket base plate 350 is sealed to the spindle mount assembly 380 to prevent liquid or gas from passing through the joint between the basket base plate 350 and the spindle mount assembly 380. The joint connecting the basket base plate 350 to the spindle mount assembly 380 can be airtight because the basket base plate 350 and the lower solid portion 330 of the sidewall 310 form an air bubble such that air cannot escape from the bubble or extraction fluid can enter the bubble through the joint between the basket base plate 350 and the spindle mount assembly 380.

[0026] 3, in an embodiment, a solid cover 390 may be attached to the housing 382 of the spindle mount assembly 380. The solid cover 390 may seal the rotating spindle 70 (FIGS. 2, 6) from the extraction fluid within the centrifuge basket 100 during operation of the industrial centrifuge 10. The spindle mount assembly 380 may be fixedly attached to the motor driven spindle 70.

[0027] In one type of chemical extraction centrifuge, the cylindrical centrifuge basket 100 can rotate counter-rotatably at rotational speeds up to about 100 revolutions per minute (RPM). However, in some embodiments, the industrial centrifuge 10 of the present disclosure can operate at rotational speeds greater than 100 RPM.

[0028] 6, the centrifuge basket 100 is placed in a cylindrical vessel 20 (curve), which is a fluid-tight container. The cylindrical vessel 20 has a releasably sealed top lid 412 and is attached to a curved base plate 430, which may be further attached to a stepped machine platform 30. The curved base plate 430 may form the bottom of the cylindrical vessel 20.

[0029] The rotating spindle 70 may be attached to the centrifuge basket 100 using a spindle mounting assembly 380. The spindle 70 passes through a spindle bearing assembly 420, 460 mounted in a bearing housing 465, which may be coupled to a curved base plate 430. The bearing housing 465 may surround the spindle bearing assembly. The curved base plate 430 may be mounted to a stepped machine platform 30. The spindle 70 may pass vertically through the spindle bearing assembly 420, 460 and extend vertically downward (e.g., in the -Z direction of the coordinate axis of FIG. 6) to engage a drive mechanism located vertically below the curved base plate 430 of the tub 20. As used herein, the term drive mechanism may refer to an electric motor 60 (FIG. 2) or other type of motor, as well as any connection between the motor 60 and the spindle 70, such as, but not limited to, a timing belt 80 shown in FIG. 2.

[0030] 6, the industrial centrifuge 10 may include a simple lip-type contact seal 440 disposed between the bottom of the spindle mount assembly 380 and the spindle bearing assembly 420. Although a lip-type contact seal 440 is shown, it is understood that other types of seals, such as, for example, face seals, may be disposed between the bottom of the spindle mount assembly 380 and the spindle bearing assembly 420.

[0031] The industrial centrifuge 10 may include an input pipe 470 and a discharge pipe 480. The input pipe 470 for the extraction fluid may be inserted through the top of the cylindrical vessel 20, such as through a sealed top cover 412. All the extraction fluid may be discharged from the kerb through the discharge pipe 480. Both the discharge pipe 480 and the bearing housing 465 may be attached to the kerb base plate 430 and sealed to prevent the extraction fluid from leaking between the kerb base plate 430 and the bearing housing 465 and discharge pipe 480.

[0032] 6 , the basket base plate 350, the lower solid portion 330 of the sidewall 310 that extends below the basket base plate 350, and at least a portion of the spindle 70 define an enclosed volume 354. In an embodiment, the enclosed volume 354 may be defined by the basket base plate 350, the lower solid portion 330 of the sidewall 310 that extends below the basket base plate 350, the housing 382 of the spindle mounting assembly 380, the lip-type contact seal 440, and at least a portion of the spindle bearing assembly 420. The enclosed volume 354 may be an annular volume defined between an inner surface of the lower solid portion 330 of the sidewall 310 and the spindle 70. In an embodiment, the enclosed volume 354 may be an annular volume defined between the inner surface 312 of the lower solid portion 330 of the sidewall 310, the outer surface of the housing 382 of the spindle mount assembly 380, the lip-type contact seal 440, the spindle 70, and the spindle bearing assembly 420. The enclosed volume 354 may extend downwardly (i.e., in the −Z direction of the coordinate axis of FIG. 6 ) from the bottom surface 352 of the basket base plate 350 to the bottom end 332 of the lower solid portion 330 of the sidewall 310.

[0033] The enclosed volume 354 may initially be filled with air prior to operation of the industrial centrifuge 10, allowing an air bubble 490 to form within the enclosed volume 354 when extraction fluid is added to the tub 20 during operation. The air bubble 490 formed in the enclosed volume 354 may provide an air seal between the extraction fluid 472 in the tub 20 and a lip-type contact seal 440 disposed between the spindle mounting assembly 380 and the spindle bearing assembly 420. The air seal formed by the air bubble 490 may reduce or prevent contact between the extraction fluid 472 and the lip-type contact seal 440, thereby reducing or preventing the extraction fluid 472 from entering the spindle bearing assemblies 420, 460.

[0034] In an embodiment, at least a portion of the spindle bearing assembly 420 may be disposed within the enclosed volume 354 such that when the tub 20 is filled with the extraction fluid 472, a portion of the spindle bearing assembly 420 may be contained within the air bubble portion 490. At least a portion of the spindle bearing assembly 420 may be disposed vertically above the bottom end 332 of the lower solid portion 330 of the sidewall portion 310. When the tub 20 is filled with the extraction fluid 472 to an operating level 475, the volume of the extraction fluid 472 within the tub 20 may act to apply a hydrostatic pressure to compress the air bubble portion of the enclosed volume 354, thereby causing the final vertical height of the extraction fluid 472 within the enclosed volume 354 to be higher than the bottom end 332 of the lower solid portion 330 of the sidewall portion 310. To compensate for this effect, the vertical distance d between the top of the spindle bearing assembly 420 and the bottom end 332 of the lower solid portion 330 of the sidewall 310 may be long enough so that the air bubble 490 trapped in the enclosed volume 354 contains at least a portion of the spindle bearing assembly 420 when the air bubble 490 is compressed by the extraction fluid 472 when filled to the operating level 475 at the operating temperature of the industrial centrifuge 10, such as a temperature of −40° C. In other words, the vertical distance d should be long enough to allow the air bubble 490 to be compressed by the extraction fluid during filling while maintaining a portion of the spindle bearing assembly 420 within the air bubble 490. The vertical distance d between the top of the spindle bearing assembly 420 and the bottom end 332 of the lower solid portion 330 of the sidewall 310 can depend on the dimensions (e.g., height) of the cylindrical vessel 20, the total volume defined by the enclosed volume 354, the operating temperature of the industrial centrifuge 10, and the physical properties of the extraction fluid 472.

[0035] In an embodiment, at least a portion of the bearing housing 465 may be disposed in the enclosed volume 354 such that when the tub 20 is filled with the extraction fluid 472, the top of the bearing housing 465 may be accommodated in the air bubble portion 490. At least a portion of the bearing housing 465 may be disposed vertically above the bottom end 332 of the lower solid portion 330 of the sidewall 310. As previously described, when the tub 20 is filled to the operating level 475, the extraction fluid 472 may compress the air bubble portion 490. Thus, the vertical distance between the top of the bearing housing 465 and the bottom end 332 of the lower solid portion 330 of the sidewall 310 may be sufficiently long such that the air bubble portion 490 trapped in the enclosed volume 354 accommodates at least a portion of the bearing housing 465 when the air bubble portion 490 is compressed by the extraction fluid 472 when filled to the operating level 475 at the operating temperature of the industrial centrifuge 10, such as a temperature of -40°C. In other words, the vertical distance should be long enough to allow the air bubble portion 490 to be compressed by the extraction fluid during filling while maintaining a portion of the bearing housing 465 within the air bubble portion 490. The vertical distance between the top of the bearing housing 465 and the bottom end 332 of the lower solid portion 330 of the sidewall 310 can depend on the dimensions (e.g., height) of the cylindrical vessel 20, the total volume defined by the enclosed volume 354, the operating temperature of the industrial centrifuge 10, and the physical properties of the extraction fluid 472.

[0036] 6, the operation of the industrial centrifuge 10 of the present disclosure will now be described. If the vessel 20 is free of extraction fluid 472, the vessel 20 may then be temporarily opened by opening the sealed top lid 412, and a biomass (not shown) from which one or more chemicals, such as, but not limited to, CBD, may be placed into the centrifuge basket 100 disposed in the vessel 20. The sealed top lid 412 may then be closed and sealed. An extraction fluid 472 at -40°F (approximately -40°C), such as, but not limited to, ethanol, heptane, or other extraction fluid, may be introduced into the vessel 20 through the input pipe 470, filling the vessel 20 to a typical operating level 475, which is just above the top of the centrifuge basket 100 from the curved base plate 430. Although not shown in FIG. 6, the extraction fluid 472 also fills the portion of the centrifuge basket 100 defined by the upper perforated portion 320 of the sidewall 310 along with the biomass. During filling of the vessel 20 with the extraction fluid 472, the increased height of the extraction fluid 472 may cause air to become trapped in the enclosed volume 354. Thus, an air bubble 490 may form in the enclosed volume 354 defined below the centrifuge basket base plate 350. This air bubble 490 may be slightly compressed air at the temperature of the extraction fluid, which is −40° F. (approximately −40° C.). The length and diameter of the lower solid portion 330 of the sidewall 310 of the centrifuge basket 100 may determine the size of the air bubble 490 and the fluid displacement volume, which is the volume of extraction fluid displaced by the air bubble 490 from the enclosed volume 354.

[0037] As previously described, the rotating spindle mounting assembly 380 may be fixedly attached to the centrifuge basket 100. The spindle bearing assembly 420 may be attached to the curved base plate 430, and the lip-type contact seal 440 may be attached to the spindle bearing assembly 420. By design, the gap between the spindle mounting assembly 380 and the spindle bearing assembly 420 may be trapped in an air bubble 490 defined by the enclosed volume 354, such that the lip-type contact seal 440 is located near the center of the air bubble 490. Thus, the air bubble 490 forms an air seal that includes the lip-type contact seal 440, thereby excluding the extraction fluid 472 from the spindle bearing assembly 420.

[0038] 6, by forming the air bubble portion 490 in the enclosed volume 354 defined below the centrifuge basket base plate 350, the total volume of the extracted fluid 472 required to fill the cylindrical vessel 20 to the operating level 475 may be reduced by the volume of the air bubble portion 490. Thus, the volume of extracted fluid 472 required to operate the industrial centrifuge 10 may be reduced.

[0039] Those skilled in the art to which the subject matter of the present disclosure pertains will recognize many variations and other embodiments of the present disclosure set forth herein upon review of the foregoing description and accompanying drawings. It is therefore understood that the subject matter of the present disclosure is not limited to the specific embodiments disclosed, and that other embodiments are intended to be within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. Preferred embodiments of the present invention will be described below in detail. EMBODIMENT 1 In an industrial centrifuge for extracting one or more compounds from biomass, A centrifuge basket disposed within a cylindrical vessel, a cylindrical sidewall including an upper perforated portion and a lower solid portion; a basket base plate connected to an inner surface of the sidewall between the upper perforated portion and the lower solid portion; a spindle coupled to the basket base plate, the spindle operably coupled to a drive mechanism operable to rotate the spindle about an axis; a centrifuge basket comprising: a spindle bearing assembly coupled to the tub and disposed between a bottom of the tub and the basket base plate; a contact seal disposed between the spindle bearing assembly and the basket base plate; Including, the spindle passes vertically through the spindle bearing assembly and extends vertically downward to the drive mechanism disposed vertically below the bottom of the cylindrical vessel; the lower solid portion of the sidewall, a portion of the spindle, and the basket base plate define an enclosed volume; At least a portion of the spindle bearing assembly is disposed within the enclosed volume; During operation of the industrial centrifuge, air trapped within the enclosed volume provides an air seal between the extraction fluid of the cylindrical vessel and the contact seal. EMBODIMENT 2 2. The industrial centrifuge of embodiment 1, wherein the central plane of the basket base plate is disposed vertically below a horizontal plane P tangent to the bottoms of the bottom row of perforations in the upper perforated portion of the side wall. EMBODIMENT 3 3. The industrial centrifuge of embodiment 1 or 2, wherein the basket base plate is sealed to the side wall to prevent liquid or gas from passing through a joint between the basket base plate and the side wall. EMBODIMENT 4 a spindle mounting assembly coupled to the basket base plate; Further including, the spindle mount assembly connects the spindle to the basket base plate; 4. The industrial centrifuge of any one of claims 1 to 3, wherein the enclosed volume includes an annular volume defined by the lower solid portion of the sidewall, the basket base plate, a housing of the spindle mounting assembly, the portion of the spindle, and the portion of the spindle bearing assembly. EMBODIMENT 5 5. The industrial centrifuge of embodiment 4, wherein the spindle mounting assembly is coupled to a bottom surface of the basket base plate. EMBODIMENT 6 6. The industrial centrifuge of embodiment 4 or 5, wherein the basket base plate is sealed to the spindle mount assembly, the seal preventing liquids or gases from passing through a joint between the basket base plate and the spindle mount assembly. EMBODIMENT 7 7. The industrial centrifuge of any one of claims 1 to 6, wherein at least a portion of the spindle bearing assembly is disposed vertically above a bottom end of the lower solid portion of the sidewall. EMBODIMENT 8 8. The industrial centrifuge of any one of claims 1 to 7, wherein a vertical distance between a lowermost end of the lower solid portion of the side wall and a point on a lowermost surface of the basket base plate is greater than a shortest vertical distance between the spindle bearing assembly and the point on the lowermost surface of the basket base plate. EMBODIMENT 9 9. The industrial centrifuge of any one of the preceding claims, wherein the spindle bearing assembly is mounted in a bearing housing that surrounds the spindle bearing assembly. EMBODIMENT 10 10. The industrial centrifuge of embodiment 9, wherein at least a portion of the bearing housing is disposed within the enclosed volume. EMBODIMENT 11 11. The industrial centrifuge of claim 9 or 10, wherein a lowermost end of the lower solid portion of the side wall is disposed vertically below at least a portion of the bearing housing. EMBODIMENT 12 12. An industrial centrifuge as described in any one of the previous embodiments, wherein the lower solid portion of the side wall of the centrifuge basket has no perforations or openings. EMBODIMENT 13 13. An industrial centrifuge as described in any one of the preceding embodiments, wherein the basket base plate is a solid, disc-shaped plate. EMBODIMENT 14 14. The industrial centrifuge of any one of the preceding embodiments, wherein the basket base plate has no perforations or openings that allow gas or fluid to flow between a lowermost surface of the basket base plate and a top surface of the basket base plate. EMBODIMENT 15 15. The industrial centrifuge of any one of the preceding embodiments, wherein the contact seal is a lip-type contact seal. EMBODIMENT 16 In the centrifuge basket of an industrial centrifuge for extracting compounds from biomass, a cylindrical sidewall including an upper perforated portion and a lower solid portion, the lower solid portion containing no perforations; a basket base plate connected to an inner surface of the sidewall between the upper perforated portion and the lower solid portion; Including, The lower solid portion of the side wall and a lowermost surface of the basket base plate define an enclosed volume operable to form an air seal between an extraction fluid and one or more bearings during operation of an industrial centrifuge including the centrifuge basket. EMBODIMENT 17 17. The centrifuge basket of embodiment 16, wherein the central plane of the basket base plate is disposed vertically below a horizontal plane P tangent to the bottoms of the bottom row of perforations in the upper perforated portion of the side wall. EMBODIMENT 18 18. The centrifuge basket of embodiment 16 or 17, wherein the basket base plate is sealed to the side wall to prevent liquids or gases from passing through the joint between the basket base plate and the side wall. EMBODIMENT 19 a spindle mounting assembly coupled to the basket base plate; Further including, the spindle mount assembly is operable to couple the basket base plate to the spindle; 19. A centrifuge basket according to any one of claims 16 to 18, wherein the enclosed volume includes an annular volume defined by the lower solid portion of the side wall, the basket base plate, a housing of the spindle mount assembly, and a portion of the spindle coupled to the spindle mount assembly. [Explanation of symbols]

[0040] 20 Cylindrical tank 70 Spindle 100 Centrifugation Baskets 310 Side wall 320 Upper perforation part 330 Lower solid part 350 Centrifuge Basket Base Plate 380 Spindle Mounting Assembly 420 Spindle Bearing Assembly

Claims

1. 1. An industrial centrifuge for extracting one or more compounds from biomass, comprising: A centrifuge basket disposed within a cylindrical vessel, a cylindrical sidewall including an upper perforated portion and a lower solid portion; a basket base plate connected to an inner surface of the sidewall between the upper perforated portion and the lower solid portion; a spindle coupled to the basket base plate, the spindle operably coupled to a drive mechanism operable to rotate the spindle about an axis; a centrifuge basket comprising: a spindle bearing assembly coupled to the tub and disposed between a bottom of the tub and the basket base plate; a contact seal disposed between the spindle bearing assembly and the basket base plate; Including, the spindle passes vertically through the spindle bearing assembly and extends vertically downward to the drive mechanism disposed vertically below the bottom of the cylindrical vessel; the lower solid portion of the sidewall, a portion of the spindle, and the basket base plate define an enclosed volume; At least a portion of the spindle bearing assembly is disposed within the enclosed volume; During operation of the industrial centrifuge, air trapped within the enclosed volume provides an air seal between the extraction fluid of the cylindrical vessel and the contact seal.

2. 2. The industrial centrifuge of claim 1, wherein a central plane of the basket base plate is disposed vertically below a horizontal plane P tangent to the bottoms of a bottom row of perforations in the upper perforated portion of the side wall.

3. 3. The industrial centrifuge of claim 1 or 2, wherein the basket base plate is sealed to the side wall to prevent liquids or gases from passing through the joint between the basket base plate and the side wall.

4. a spindle mounting assembly coupled to the basket base plate; Further including, the spindle mount assembly connects the spindle to the basket base plate; 4. The industrial centrifuge of claim 1, wherein the enclosed volume includes an annular volume defined by the lower solid portion of the sidewall, the basket base plate, a housing of the spindle mounting assembly, the portion of the spindle, and the portion of the spindle bearing assembly.

5. 5. The industrial centrifuge of claim 4, wherein the spindle mounting assembly is coupled to a bottom surface of the basket base plate.

6. 6. The industrial centrifuge of claim 4 or 5, wherein the basket base plate is sealed to the spindle mount assembly, the seal preventing liquids or gases from passing through the joint between the basket base plate and the spindle mount assembly.

7. 7. The industrial centrifuge of claim 1, wherein at least a portion of the spindle bearing assembly is disposed vertically above a lowermost end of the lower solid portion of the sidewall.

8. 8. The industrial centrifuge of claim 1, wherein a vertical distance between a lowermost end of the lower solid portion of the side wall and a point on a lowermost surface of the basket base plate is greater than a shortest vertical distance between the spindle bearing assembly and said point on the lowermost surface of the basket base plate.

9. 9. The industrial centrifuge of claim 1, wherein the spindle bearing assembly is mounted in a bearing housing that surrounds the spindle bearing assembly.

10. 10. The industrial centrifuge of claim 9, wherein at least a portion of the bearing housing is disposed within the enclosed volume.

11. 11. The industrial centrifuge of claim 9 or 10, wherein a lowermost end of the lower solid portion of the side wall is disposed vertically below at least a portion of the bearing housing.

12. 12. The industrial centrifuge of claim 1, wherein the lower solid portion of the side wall of the centrifuge basket is free of perforations or openings.

13. 13. The industrial centrifuge of claim 1, wherein the basket base plate is a solid, disc-shaped plate.

14. 14. The industrial centrifuge of any one of claims 1 to 13, wherein the basket base plate has no perforations or openings that would allow gas or fluid to flow between a lowermost surface of the basket base plate and a top surface of the basket base plate.

15. 15. The industrial centrifuge of claim 1, wherein the contact seal is a lip-type contact seal.

16. In the centrifuge basket of an industrial centrifuge for extracting compounds from biomass, a cylindrical sidewall including an upper perforated portion and a lower solid portion, the lower solid portion containing no perforations; a basket base plate connected to an inner surface of the sidewall between the upper perforated portion and the lower solid portion; Including, The lower solid portion of the side wall and a lowermost surface of the basket base plate define an enclosed volume operable to form an air seal between an extraction fluid and one or more bearings during operation of an industrial centrifuge including the centrifuge basket.

17. 17. The centrifuge basket of claim 16, wherein a central plane of the basket base plate is disposed vertically below a horizontal plane P tangent to the bottoms of a bottom row of perforations in the upper perforated portion of the side wall.

18. 18. The centrifuge basket of claim 16 or 17, wherein the basket base plate is sealed to the side wall to prevent liquids or gases from passing through the junction between the basket base plate and the side wall.

19. a spindle mounting assembly coupled to the basket base plate; Further including, the spindle mount assembly is operable to couple the basket base plate to the spindle; 19. The centrifuge basket of claim 16, wherein the enclosed volume includes an annular volume defined by the lower solid portion of the sidewall, the basket base plate, a housing of the spindle mount assembly, and a portion of the spindle coupled to the spindle mount assembly.

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