Patent Publication Number: US-2020290057-A1

Title: Botanical Quick Freeze Method and System

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. provisional application Ser. No. 62/801,672 filed Feb. 6,2019, the entire contents of which is hereby incorporated by reference thereto. 
    
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     This invention is directed to a method and apparatus providing for the preparation of botanical biomass to enhance solvent extraction process. 
     Description of Related Arts 
     There are many well-known solvent based extractions methods and apparatus to realize solvent based extractions. For example; Supercritical carbon dioxide can be an effective solvent extraction method when utilized at certain temperatures and pressures. Hydrocarbons such as butane and hexane can be an effective solvent extraction method when utilized at certain temperatures and pressures. Ethanol can be an effective solvent extraction method when utilized at certain temperatures and pressures. 
     The efficiency of solvent based extraction methods is very dependent on the mechanics of the method used to expose botanical biomass to the solvent. Critical variables of the method utilized to expose botanical biomass to a solvent that have the most impact on quality and efficiency are: a) the saturation level of the solvent, b) the amount of time where the biomass is exposed to the solvent, c) the temperature of the solvent, d) the temperature of the biomass, and e) the surface area volume ratio of the biomass. It is a critical first step to properly prepare the botanical biomass so as to align with and enhance the solvent extraction process. 
     Typical industrial preparation technology includes first reducing the size of the botanical biomass via milling. Most often this is a manual process where a technician visually determines the correct amount of reduction applied to the botanical biomass. This manual procedure that relies on the skill and diligence of the technician is at best unreliable. 
     Other industrial milling technology utilizes a screen to control the size of the finished material. There is a practical limitation to the minimum size obtainable by this technology. Very small screen openings cannot be used when processing botanical biomass without risk of blinding or plugging. 
     A next step typical of current botanical biomass preparation is to reduce the temperature to stabilize the light end constituents of the botanical oil and to reduce the activity of the water-soluble constituents. Again, current technology is a manual process where a technician spreads the botanical biomass onto a tray to subsequently be placed in a freezer. After some time has passed, usually 24 hrs, the prepared botanical biomass is deemed ready for the solvent extraction process. 
     Current technology utilized within the industry does not provide for a means of precisely controlling the variables associated with preparation of botanical biomass for subsequent solvent extraction processes. 
     Therefore, there is a need for a method and apparatus that sufficiently controls the variables associated with preparation of botanical biomass for subsequent solvent extraction processes. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention addresses these and other needs by providing a system and apparatus that sufficiently controls the variables associated with preparation of botanical biomass for subsequent solvent extraction processes. 
     The new and unique features of this invention include a milling device rotating at a high rate of speed. The milling device is of a radial blade design encased in a housing with a principally circular shaped inlet that is concentrically aligned with the axis of rotation of the rotating radial milling feature. The housing also includes a principally circular shaped outlet that is tangent to the arc formed at the periphery of the rotating radial blade. The outlet is in conveyance communication with a heat exchanger to remove heat from the milled botanical biomass. The heat exchanger is in further conveyance communication with the inlet of the housing via the branch of a suitable tee connection. The run of the tee is connected to the housing and a suitable feed conveyor. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a detailed description of the preferred embodiment of this invention, reference will be made to the accompany drawing.  FIG. 1  is a schematic flow diagram of a process and apparatus according to an embodiment of the invention 
     
    
    
     DETAILED DESCRIPTION OF AN EMBODIMENT 
       FIG. 1  depicts flow diagram  100  of the process of this invention. Flow diagram  100  includes feed conveyor  110  that includes outlet  120 . Outlet  120  is mechanically coupled to and in mechanical conveyance communication with Inlet  130  of cyclone  140 . Outlet  150  of cyclone  140  is mechanically coupled to and in pneumatic communication with Inlet  160  of radial miller  170 . Outlet  180  of radial miller  170  is mechanically coupled to and in pneumatic communication with Inlet  190  of heat exchanger  200 . Outlet  220  of heat exchanger  200  is mechanically coupled to and in pneumatic communication with inlet  230  of diverter valve  360 . Outlet  240  of diverter valve  360  is mechanically coupled to and in pneumatic communication with inlet  250  of cyclone  140 . 
     Outlet  260  of diverter valve  360  is mechanically coupled to and in pneumatic communication with inlet  270  of cyclone  300 . Outlet  290  of cyclone  140  is mechanically coupled to and in pneumatic communication with Inlet  280  of Cyclone  300 . Outlet  330  of cyclone  300  is mechanically coupled to and in mechanical conveyance communication with inlet  340  of discharge conveyor  350 . Outlet  310  of cyclone  300  is mechanically coupled to and in pneumatic communication with atmospheric vent  320 . 
     A pneumatic loop is formed via outlet  150  of cyclone  140 , inlet  160  of radial miller  170 , radial miller  170 , Outlet  180  of radial miller  170 , inlet  190  of heat exchanger  200 , heat exchanger  200 , outlet  220  of heat exchanger  200 , inlet  230  of diverter valve  360 , diverter valve  360 , outlet  240  of diverter valve  360 , inlet  250  of cyclone  140 , and cyclone  140 . The pneumatic loop will be referenced herein as the “operating loop”. 
     Again, referring to  FIG. 1 . and now describing in detail a method according to an embodiment of this invention. 
     Processing begins with initialization of the system in preparation of receiving botanical biomass including confirmation that diverter valve  360  is configured so that inlet  230  of diverter, valve  360  is in pneumatic communication with outlet  240  of diverter valve  360 , radial miller  170  is operating at a sufficient speed, and the pneumatic velocity within the operating loop is stable and sufficient. The just describe initialization, resultant configuration, and intended functionality is referred to as “milling cycle”. Subsequent to initialization and now describing the milling cycle, previously screened botanical biomass suitable for solvent extraction and compatible with the method of this invention is received at feed conveyor  110 . Botanical biomass received at feed conveyor  110  is discharged at outlet  120  of feed conveyor  110 . Botanical biomass discharged at outlet  120  of feed conveyor  110  is mechanically conveyed to and received at inlet  130  of cyclone  140 . 
     Feed conveyor  110  is of a variable conveyance rate design. The conveyance rate of feed conveyor  110  is modulated based on the pressure within the operating loop measured near, but downstream, of outlet  180  of radial miller  170 . Botanical biomass from the feed source is mechanically conveyed via feed conveyor  110 , Outlet  120  of feed conveyor  110 , and inlet  130  of cyclone  140  into the operating loop at cyclone  140 . Once a sufficient amount of botanical biomass has been introduced into the operating loop, based on the measured pressure at outlet  180  of radial miller  170 , feed conveyor  110  will pause, reducing the conveyance rate to zero. 
     Botanical biomass received at cyclone  140  is, pneumatically conveyed via outlet  150  of cyclone  140  and inlet  160  of radial miller  170  into radial miller  170  very near the axis of rotation of radial miller  170 . 
     Radial miller  170  is of a radial blade design. Each radial blade of radial miller  170  features a precision, replaceable, cutting blade. Radial miller  170  is designed to create both centrifugal and pneumatic forces. The centrifugal and pneumatic forces act upon both the gas and botanical biomass within radial miller  170  affecting the gas within radial miller  170  to compress at the periphery of the housing of radial miller  170  and affecting the botanical biomass to congregate at the periphery of the housing of radial miller  170 . The compressed gas and the botanical biomass are subsequently discharged at Outlet  180  of radial miller  170 . Outlet  180  of radial miller  170  is located principally tangent to, the axis of rotation at the periphery of the housing of radial miller  170 . 
     Outlet  180  of radial miller  170  features a cutting blade designed to interface with the cutting blade of the radial blade feature of radial miller  170 . As botanical biomass transitions from the interior portion of the housing of radial miller  170  to outlet  180  it is exposed to the interfacing cutting blade of outlet  180  and the cutting blade of the radial blade of radial miller  170 . 
     Radial miller  170  may feature one or more radial blades. Additionally, outlet  180  of radial miller  170  may future one or more cutting blades. 
     The gas and botanical biomass discharged at outlet  180  of radial miller  170  is pneumatically conveyed to and received at inlet  190  of heat exchanger  200 . 
     Heat exchanger  200  is of a cryogenic design where a cryogenic liquid, such as cotton dioxide or nitrogen is sprayed, in a fine mist, onto the exposed surfaces of the milled botanical biomass. Heat exchanger  200  is of sufficient capacity to “flash freeze” the botanical biomass as it passes through heat exchanger  200 . 
     Flash freezing is a known art and commonly used in biomass preparation such as fruits and vegetables for human consumption. 
     The compressed gas and flash frozen botanical biomass are discharged at outlet  220  of heat exchanger  200 . The compressed gas and flash frozen botanical biomass discharged at outlet  220  of heat exchanger  240  is pneumatically conveyed to and received at inlet  230  of diverter valve  360 . As previously disclosed, diverter valve  360  is configured, during milling operations, to discharge at outlet  240 . Compressed gas and botanical biomass discharged at outlet  240  of diverter valve  360  is pneumatically conveyed to and received at inlet  250  of cyclone  140 . 
     Cyclone  140  allows for the velocity of the pneumatic transport gas and the gas produced by the evaporating cryogenic fluid to slow sufficiently enough to no longer support conveyance of the botanical biomass. Cyclone  140  is vented to atmosphere via outlet  290  of cyclone  140 , inlet  280  of cyclone  300 , cyclone  300 , outlet  310  of cyclone  300 , and atmospheric vent  320 . Cyclone  300  is vented to atmosphere via outlet  310  and atmospheric vent  320  to allow pressure equilibrium within the pneumatic loop. 
     Botanical biomass received at inlet  250  of cyclone  140  is discharged at outlet  150  of cyclone  140 . Botanical biomass discharged at outlet  150  of cyclone  140  is pneumatically conveyed to and received at inlet  160  of radial miller  170 . 
     Botanical biomass will continue to loop through the described operating loop for a certain amount of time with each loop causing a certain size reduction of the botanical biomass. 
     After a sufficient amount of time necessary to reduce the botanical biomass to an optimal extraction size, diverter valve  360  is configured to discharge at outlet  260 . 
     This configuration where diverter valve  360  is configured to discharge at outlet  260  is herein referred to as the “discharge cycle”. 
     Compressed gas and botanical biomass discharged at outlet  260  of diverter valve  360  is pneumatically conveyed to and received at inlet  270  of cyclone  300 . 
     Cyclone  300  allows for the velocity of the pneumatic transport gas and the gas produced by the evaporating cryogenic fluid to slow sufficiently enough to no longer support conveyance of the botanical biomass. Cyclone  300  is vented to atmosphere via outlet  310  of cyclone  300  and atmospheric vent  320 . 
     Botanical biomass received at runlet  270  of cyclone  300  is discharged at outlet  330  of cyclone  300 . Botanical biomass discharged at outlet  330  of cyclone  300  is conveyed to and received at Inlet  340  of discharge conveyor  350 . 
     The just described cycles where the system of the invention is first configured for a milling cycle and subsequently configured for a discharge cycle constitutes one complete batch cycle. As many batch cycles as necessary to meet the demands of production requirements are completed in a fully automated, computer-controlled sequence. 
     Utilizing the new and unique features of the current invention provides for a fully automatic method and system to precisely control the comminution and concurrent flash freezing of botanical biomass in preparation for a solvent extraction process. 
     Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations may be made herein without departing from the spirit and scope of the invention as defined by the appended claims.