Method and apparatus for manufacture of biodegradable polymer

Abstract

An apparatus for manufacture of a biodegradable polymer composite is provided. The apparatus include a material discharge unit; a mixing and drying unit comprising a descant dryer and a vacuum drying assisted ribbon blender each being connected to the material discharge unit by a pneumatic conveying system; a dosing unit comprising a first feeder connected to the descant dryer for receiving a first raw material and a second feeder connected to the vacuum drying assisted ribbon blender for receiving a second raw material; an extrusion unit for receiving the first raw material and the second raw material from the first feeder and the second feeder, respectively; and a controller and sensors in communication with the material discharge unit, the mixing and drying unit, the dosing unit and the extrusion unit via a network. The controller provides a virtual apparatus in order to facilitate management of stock and flows of materials through the apparatus.

Description

METHOD AND APPARATUS FOR MANUFACTURE OF BIODEGRADABLE POLYMERRelated

[0001] This application claims benefit of US Patent Application No. 63 / 562,972 filed on March 8, 2024.Technical Field

[0002] The present invention relates generally to a method and apparatus for manufacture of biodegradable polymer composites and in particular, an automation and material handling system for biodegradable polymer processing.

[0003] The era of plastics and polymers has undeniably marked a significant chapter in human history, contributing advantageous properties to diverse fields, ranging from the automotive industry to electronics. However, the disposal of plastic-based products and packaging has evolved into a substantial environmental challenge. Packaging alone accounts for a substantial one-third portion of global plastic use, compelling nations to prioritize recycling efforts. Unfortunately, the extensive presence of plastics in oceans has emerged as a pressing concern, with the potential long-term impact of microplastics on human and animal health, as well as ecosystems.

[0004] Recognizing the predominant role of plastics in packaging, the substitution of traditional plastics with biodegradable polymers emerges as a tangible solution, promising immediate positive effects. Biodegradable polymers align with the overarching trend of a circular economy. Various examples, including polyhydroxyalkanoate (PHA), polybutylene Succinate (PBS), polyglycolic Acid (PGA), polycaprolactone (PCL), Cellulose Acetate (CA), Poly(butylene adipate-co-terephthalate) (PBAT), and starch-based polymers, have been explored, at least on a process scale.

[0005] Poly(lactic acid) (PLA), while considered a biodegradable polymer, has serious limitations that may impact its overall environmental sustainability. One significant drawback is its relatively slow rate of biodegradation. PLA requires specific conditions to break down efficiently, typically industrial composting facilities with controlled temperature and humidity. In natural environments or landfills, where such conditions are not consistently met, PLA may persist for a prolonged period like the traditional plastics, hindering its biodegradability. Theescalating demand for biodegradable polymers arises from heightened environmental awareness, regulatory pressures, and consumer preferences favoring sustainable materials.

[0006] Biodegradable polymers offer a promising solution, demonstrating the potential to mitigate environmental impact and reduce reliance on traditional plastics. However, the compounding of biodegradable polymers presents unique challenges like stickiness, moisture sensitivity, low crystallization rate, shear sensitivity, low thermal stability, limited processability that necessitate specialized handling and processing techniques. Through sophisticated compounding techniques, various challenges associated with biodegradable polymers, such as low mechanical properties, processing difficulties, and high costs, may be addressed along with improved quality.

[0007] In addition to compounding techniques, additives, such as fillers and reinforcements, may help compounded biodegradable polymers exhibit improved performance, allowing for customization of properties like strength, flexibility, and degradation rates. This process may also facilitate the optimization of biodegradability characteristics, tailoring the materials to break down efficiently in different environments.

[0008] Polymer compounding is a complex process that demands precision in handling various materials, from polymer pellets to sticky additives and fillers. Processing of different polymers can entail different processing parameters. The conventional bulk bag handling methods have limitations in terms of efficiency, accuracy, and potential material degradation.

[0009] There remains a general desire for an improved method and apparatus for manufacture of biodegradable polymer composites and in particular, an automation and material handling system for biodegradable polymer processing.

[0010] The foregoing examples of the related art and limitations related thereto are intended to be illustrative and not exclusive. Other limitations of the related art will become apparent to those of skill in the art upon a reading of the specification and a study of the drawings.Summary

[0011] The following embodiments and aspects thereof are described and illustrated in conjunction with systems, tools and methods which are meant to be exemplary and illustrative, not limiting in scope. In various embodiments, one or more of the above-described problems have been reduced or eliminated, while other embodiments are directed to other improvements.

[0012] The present invention has a number of aspects. These aspects include without limitation:• a method for manufacture of biodegradable polymer composites;• a biodegradable polymer processing method;• an apparatus for manufacture of biodegradable polymer composites; and• an automation and material handling system for biodegradable polymer processing.

[0013] In one aspect, a new and useful apparatus for manufacture of a biodegradable polymer composite. Some advantages that may be provided by some embodiments of the apparatus include that:• the apparatus enables an automated method for biodegradable polymer compounding, integrating a material handling system to optimize efficiency and quality control;• the apparatus permits precision, consistency, and safety in a polymer compounding process;• the apparatus allows for streamlining the compounding process and enhancing the scalability, quality, and sustainability of biodegradable polymer production;• the apparatus permits the precise measure, mix, and process of ingredients needed for a biodegradable polymer composite;• the apparatus includes sensors for real-time quality monitoring, wherein the sensors are configured to monitor the ratio of a polymer, a filler, and an additive;• the apparatus enables a certain level of automation, which can lessen manual intervention, reduce contamination risk, and improve health and safety; and• the apparatus facilitates traceability throughout the manufacturing process.

[0014] One aspect relates to an apparatus for manufacture of a biodegradable polymer composite. The apparatus includes several connected units, including a material discharge unit having a first discharging hopper, a second discharging hopper, and a mobile drive unit positioned above the first discharging hopper and the second discharging hopper, the mobile drive unit being configured to transport a first raw material and a second raw material to the first discharging hopper and the second discharging hopper, respectively; a mixing and drying unit comprising a descant dryer connected to the first discharging hopper by a first pneumatic conveying system and a vacuum drying assisted ribbon blender connected to the seconddischarging hopper by a second pneumatic conveying system, the descant dryer including a screw-type mixing system therein for mixing the first raw material and the vacuum drying assisted ribbon blender including a blade therein for mixing the second raw material; a dosing unit comprising a first feeder connected to the descant dryer for receiving the dried and mixed first raw material and a second feeder connected to the vacuum drying assisted ribbon blender for receiving the dried and mixed second raw material; and an extrusion unit connected to the dosing unit and for receiving and compounding the dried and mixed first raw material and the dried and mixed second raw material to extrude the biodegradable polymer composite. The apparatus also includes a controller and sensors in communication with the material discharge unit, the mixing and drying unit, the dosing unit and the extrusion unit via a network, wherein the controller provides a virtual apparatus in order to facilitate management of stock and flows of materials through the apparatus.

[0015] The material discharge unit may include an overhead crane system in which one or more crane assemblies positioned above the first discharging hopper and the second discharging hopper and the one or more crane assemblies are capable of moving within a network of wires or rails to a position suitable to discharge the first raw material and the second raw material to the first discharging hopper and the second discharging hopper, respectively. The overhead crane system is in communication with the controller and the sensors. The controller and the sensors monitor discharge rates of the first discharging hopper and the second discharging hopper. The controller comprises a closed-loop feedback system to dynamically adjust the discharge rates to maintain a pre-determined recipe proportion.

[0016] The controller and the sensors may monitor discharge rates of the first feeder and the second feeder and may include a closed-loop feedback system to dynamically adjust the discharge rates to maintain a pre-determined recipe proportion.

[0017] The apparatus may include a first weighing station; a second weighing station; a first screw conveyor connecting the first discharging hopper and the first weighing station; and a second screw conveyor connecting the second discharging hopper and the second weighing station. The second screw conveyor has a screw flight that has a tighter pitch and a larger diameter than that of the first screw conveyor, making the second screw more suitable to handle nano- and / or micro-filler.

[0018] The first discharge hopper and / or the second discharge hopper may have a wedge- shaped hopper with a generally rectangular cross-section and curved edges, be coated with an antistick formulation and / or an anti-static formulation, and / or have a silo fluidizer.

[0019] The apparatus may have a liquid feeder connected to the extrusion unit and configured to add an additive to the dried and mixed first raw material and the dried and mixed second raw material in the extrusion unit.

[0020] The apparatus may include a liquid feeder being upstream of and connected to the second feeder and the liquid feeder being configured to add an additive to the dried and mixed second raw material in the second feeder. The second feeder may include a heating element and / or a mixing element to enable a chemical reaction between the dried and mixed second raw material and the additive prior to feeding the mixture to the extrusion unit.

[0021] The extrusion unit may be a twin-screw extruder, wherein the twin-screw extruder has a temperature-controlled barrel, including a feeding zone maintained at a first temperature, a compression zone maintained at a second temperature, a metering zone maintained at a third temperature, and a vacuum zone; the first feeder and the second feeder feed the first mixed and dried raw material and the second mixed and dried raw material to the feeding zone; the compression zone is downstream of the feeding zone and is where the first mixed and dried raw material and the second mixed and dried raw material are mixed and melted; the metering zone is downstream of the compression zone and is where further mixing, dispersive, and distributive mixing activities take place; and the vacuum zoom is positioned above the metering zone and facilitate moisture and gas removal from the temperature-controlled barrel.

[0022] The twin-screw extruder may include heat exchangers positioned along temperature- controlled barrel to facilitate the transfer of thermal energy from the extruded biodegradable polymer composite to a heat exchange medium, a regenerative braking mechanism to recover and convert kinetic energy generated from the extruded biodegradable polymer composite into reusable electrical energy, and / or a band heater positioned outside of the temperature-controlled barrel.

[0023] The apparatus may include an air cooling unit and a vision monitoring system programmed to capture images of the extruded biodegradable polymer composite and analyze the images to assess the quality of the extruded biodegradable polymer composite.

[0024] The vision monitoring system may be programed to conduct spectral analysis to detect a change in the chemical and physical properties of the extruded biodegradable polymercomposite, wherein if the detected change exceeds a pre-determined range, the vision monitoring system generates a signal to alert an operator of the change.

[0025] The apparatus may include an inline quality testing and sorting mechanism system, wherein the inline quality testing and sorting mechanism system includes cameras and sensors to visually inspect the extruded biodegradable polymer composite.

[0026] The inline quality testing and sorting mechanism system may include a spectrometer for analyzing spectral characteristics of the extruded biodegradable polymer composite. If the inline quality testing and sorting mechanism system determines a change in the spectral characteristics that is beyond a pre-determined range, the inline quality testing and sorting mechanism system initiates a sorting process to isolate the extruded biodegradable polymer composite associated with the change.

[0027] The apparatus may include an air cooling unit being downstream of the extrusion unit, the air cooling unit for receiving and air cooling the extruded biodegradable polymer composite; a pelletizing unit being downstream of the air cooling unit, wherein the pelletizing unit receives the air cooled extruded biodegradable polymer composite and processes the biodegradable polymer composite into pellets; and a storage and packaging unit including multiple silos and each silo including a vacuum loader, facilitating material transfer from the pelletizing unit to the silo.

[0028] In addition to the exemplary aspects and embodiments described above, further aspects and embodiments will become apparent by reference to the drawings and by study of the following detailed descriptions.Brief Description of the Drawings

[0029] Exemplary embodiments are illustrated in referenced figures of the drawings. It is intended that the embodiments and figures disclosed herein are to be considered illustrative rather than restrictive.

[0030] FIG. 1 shows a perspective view of an apparatus for manufacture of biodegradable polymer composites according to an example embodiment.

[0031] FIG. 2A shows a perspective view of a material discharge unit of the embodiment of FIG. 1.

[0032] FIG. 2B shows a top view of the material discharge unit of FIG. 2A.

[0033] FIG. 2C shows a side view of the material discharge unit of FIG. 2A.

[0034] FIG. 2D shows a front view of the material discharge unit of FIG. 2A.

[0035] FIG. 3A shows a perspective view of a mixing and drying unit of the embodiment of FIG. 1.

[0036] FIG. 3B shows a top view of the mixing and drying unit of FIG. 3A.

[0037] FIG. 3C shows a side view of the mixing and drying unit of FIG. 3A.

[0038] FIG. 3D shows a front view of the mixing and drying unit of FIG. 3A.

[0039] FIG. 4 shows a schematic drawing of an extrusion unit of the embodiment of FIG. 1 .

[0040] FIG. 4A shows a side view of the extrusion unit of FIG. 4.

[0041] FIG. 4B shows a front view of the extrusion unit of FIG. 4, wherein certain components have been omitted for clarify and a dosing unit is shown.

[0042] FIG. 4C shows a front view of the extrusion unit of FIG. 4, wherein certain components have been omitted for clarify and a vacuum system is shown.

[0043] FIG. 4D shows a side view of the extrusion unit of FIG. 4 opposite to the side view of FIG. 4A.

[0044] FIG. 5 shows a schematic drawing of a screw used in the extrusion unit of FIG. 4.

[0045] FIG. 6 shows a top view of the extrusion unit of FIG. 4 and an air cooling unit and pelletizer unit being downstream of the extrusion unit.

[0046] FIG. 6A shows a side view of units of FIG. 6.

[0047] FIG. 7A shows a perspective view of a storage and packaging unit of the embodiment of FIG. 1.

[0048] FIG. 7B shows a top view of the storage and packaging unit of FIG. 7A.

[0049] FIG. 7C shows a side view of the storage and packaging unit of FIG. 7A.

[0050] FIG. 7D shows a front view of the storage and packaging unit of FIG. 7A.

[0051] FIG. 8 shows a schematic drawing of a powderization unit according to an example embodiment.

[0052] FIG. 9 shows a perspective view of a shredder of the powderization unit of FIG. 8.

[0053] FIG. 10 shows a perspective view of a first inclined cleated conveyor of the powderization unit of FIG. 8.

[0054] FIG. 11 shows a perspective view of an ultrasonic bath of the powderization unit of FIG. 8.

[0055] FIG. 12 shows a perspective view of a second inclined cleated conveyor of the powderization unit of FIG. 8.

[0056] FIG. 13 shows a perspective view of a hammer milling machine of the powderization unit of FIG. 8.Description

[0057] Several embodiments will be now described to set forth specific details in order to provide a more thorough understanding of the present invention to persons skilled in the art. The description may use perspective-based descriptions such as upstream and downstream to facilitate the discussion. The following description sets forth specific details in order to provide a more thorough understanding to persons skilled in the art. Well-known elements may not have been shown or described in detail to avoid unnecessarily obscuring the disclosure. The description and drawings are to be regarded in an illustrative, rather than a restrictive, sense. Reference will now be made to the drawings wherein like reference numerals identify similar structural features or aspects of the present invention.

[0058] The inventor has now developed a method and apparatus for manufacture of biodegradable polymer composites. Some advantages that may be provided by some embodiments of the method and / or apparatus include that:• The apparatus includes sensors and deploys machine learning algorithms for precise measurement and dispensing of biodegradable polymer pellets and additives.• Certain manufacturing steps are automated, which enables an increased throughout compared to similar systems known in the art.• The apparatus includes sensors for real-time quality monitoring and controlling of a polymer compounding process.• The apparatus allows for streamlining the compounding process and enhancing the scalability, quality, and sustainability of biodegradable polymer production.• Automation in material handling, compounding, and downstream processing enables a continuous and controlled workflow, improving overall production efficiency.• The apparatus facilitates traceability throughout a polymer compounding process, supporting accountability and compliance with regulatory standards.• The apparatus includes both screw conveyors and pneumatic conveyors, which the inventor believes would provide efficient transfer of powered or granular biodegradable polymers within a process line.• The apparatus includes modular components, which enables the handling of different bulk materials.• The apparatus includes modular units that provide a level of flexibility and variety in use, wherein the modular units include an extrusion unit, units upstream to the extrusion unit, such as a material discharge unit and a mixing and drying unit, and units downstream to the extrusion unit, such as a cooling and pelletizing unit and a packaging and storage unit.

[0059] FIG. 1 shows an apparatus for manufacture of biodegradable polymer composites 100. In some embodiments, the apparatus 100 is used to compound a polymer, including a biodegradable polymer that is not PLA.

[0060] The apparatus 100 has a modular setup, including several units. The assembly of the units may take only a few minutes to setup, take apart, repair, or reinstall, thereby lessening the impact of and minimizing production shutdown. In addition, setup may not require any welding and as such, maintenance tasks can be simplified. The units may be made of materials that are highly resistant to abrasion, corrosion as well as acids and bases. The units may also use non-stick coating and the resulting non-stick properties would allow a material flow improvement with noise reduction properties.

[0061] With reference to FIG. 1 , the apparatus 100 has a material discharge unit 110, a mixing and drying unit 132, an extrusion unit 214, a dosing unit 168, an air cooling unit 205, a pelletizing unit 206, and a storage and packaging unit 184. These units are operably connected to one another and their spatial relationship to one another may be described using perspective-based descriptions such as upstream and downstream to facilitate the discussion and these descriptions are not intended to restrict the application of the disclosed embodiments. As used herein, "upstream" means a direction towards an inlet where a material enters into the apparatus 100 or one of its units and "downstream" means a direction towards an outlet where the material exits from the apparatus 100 or one of its units.

[0062] In operation and with respect to a polymer compounding process, raw ingredients, e.g. a polymer in a granular form and a filler in a powder form, are separately measured and discharged from the material discharge unit 110 to the mixing and drying unit 132. The raw ingredients are separately mixed and dried. The dried and mixed raw ingredients are separately dosed with the applicable additive(s) using the dosing unit 168 (which may be a gravimetric feeder). The dosed mixtures each are fed to the extrusion unit 214, where they undergo controlled melting and compounding. After the compounding process, the extrusion unit 204 outputs extruded polymer strands, which are cooled by air using the air cooling unit202, which may help prevent hydrolytic degradation and moisture / water uptake and ensure uniformity. The cooled polymer strands are shaped to uniform pellets using the pelletizing unit 206. The pellets are then moved to the storage and packaging unit 184, which may include a silo equipped with automated temperature and humidity controls to maintain material integrity. The apparatus 100 may employ sensors for real-time monitoring, ensuring quality throughout the storage phase and facilitating the automation of certain steps.

[0063] Better shown in FIGS. 2A-2D, a material discharge unit 110 is illustrated. Not shown in the figures may be a conveyance such as a chute, conveyor belt, series of shuttles, or the like that moves raw material items into the material discharge unit 110. The raw material items may be handled by human or robotically handled, for example scanned via a sensor such as an optical, RFID, or comparable scanner.

[0064] The material discharge unit 110 is directed by a controller 130, which includes a processor and a memory. The controller 130 may communicate with other units via a network, such as a wireless network. A virtual representation of the material discharge process or protocol may be maintained by the controller in order to facilitate control over the movement of the raw material items.

[0065] The material discharge unit 110 has a mobile drive unit 112 configured to transport and / or facilitate the transport of the raw material items, for example to load and unload bulk bags 116. In the illustrated embodiment, the mobile drive unit 112 could be characterized as a motorized remote controlled chain system for loading and unloading bulk bags. In particular, the mobile drive unit 112 is an overhead crane system 150 in which one or more crane assemblies 152 positioned above discharging hoppers 118 are capable of moving within a network of wires or rails 154 to a position suitable to discharge the raw material items. The overhead crane system 150 includes pillars with hooks 114 to hold bulk bags 116 stationary. The mobile drive unit 112 may include one or more load sensors 120 configured to detect or determine the location of the crane assemblies.

[0066] In operation, the crane assembly 152 lifts a raw material item and move within the rails 154 to a position directly above a discharging hopper 118 and suitable to discharge the raw material item.

[0067] If the raw material item is a bag containing raw material, a precise cut at the bag's end can impact the seamless release of raw material into the discharging hopper 118 below. In some embodiments, the crane assembly 152 may include a robotic arm with scissors to enable a precise cut of the bag.

[0068] Discharging hoppers 118 may be configured to accommodate different raw materials. For example, a hopper 118 may include agitators to promote flow of a material. In addition, a hopper 118 may be configured to minimize material buildup, for example by facilitating programmed periodic hammering and reducing the risk of material blockage. The shape of a hopper 118 may cause segregation, with smaller particles tending to channel, depending on the slopes of the surfaces and angle of repose of the particle components. Smaller particles can even flow through the larger particles, causing separation, such as with fine powders. Particles with much higher densities, such as metallic fillers, will segregate based on weight. Friction on the walls of the solids flow surfaces, such as the hopper walls, varies with the solid additive as well as surface roughness and frictional coefficient. Additionally, there is particle- to-particle friction that can cause segregation. The inventor found that a cone-type hopper as shown in FIGS. 2A-2D can be useful for a relatively sticky material.

[0069] In some embodiments, the discharging hopper 118 is a wedge-shaped hopper with a generally rectangular cross-section and curved edges. The inventor observed that such a configuration can help minimize material retention points. The hopper 118 may be coated with a chemical formation or covered by a liner to achieve certain desirable properties. For example, the inner wall of the discharging hopper 118 may be coated with an antistick formulation, thereby reducing material adhesion to the inner wall and waste generation. The inner wall may be coated with an anti-static formulation, thereby eliminating static charge and promoting free material flow without agglomeration. An anti-static coating may ensure a smoother and more predictable material discharge and contribute to improved safety in handling potentially combustible powders.

[0070] The discharging hopper 118 may include a silo fluidizer. The silo fluidizer is configured to provide controlled bursts of air to dislodge potential blockages and maintain consistent material discharge through the discharging hopper 118. The inventor believes that the synergistic combination of a generally rectangular cross-section, curved edges, an antistick costing, an anti-static coating, and a silo fluidizer results in improved operational efficiency, reduced material waste, and enhanced safety.

[0071] The material discharge unit 110 includes a weighing station 126. The raw material is transferred from the discharging hopper 118 to the weighing station 126 using screw conveyors 124 (elsewhere may be referred to as a screw conveyor system). Screw conveyors 124 can provide precise and accurate measurements even for materials with varying densities. A screw conveyor 124, also called an auger, is a mechanical conveying device forpowder bulk solids. The components of the screw conveying system 124 typically includes the conveyor screw, trough, hanger bearings, couplings, internal collar, end lugs, and electric motor. The trough ends hold the bearings which support the shafts connected to the screw. The coupling bolts transmit the torque from the drive shaft to the screw and then ultimately the conveyed material. The shaft seals keep the conveyed material in the screw conveyor. The trough is there to provide a conveying surface for the conveyed material and the cover encloses the screw conveyor, while still allowing access to the internal components for maintenance. For long screw conveyors the hanger and hanger bearing act as intermediate supports to allow the screw conveyor to conveyor material up to hundreds of feet. The inlet and discharge allow material to enter and leave the screw conveyor. The screw conveyor drive is responsible for providing the power to move the material.

[0072] In some embodiments, a first screw conveyor 124 is used to connect a first discharging hopper 118 and a first weighing station 126 and a second screw conveyor 124’ is used to connect a second discharging hopper 118 and a second weight station 126’. The first screw conveyor 124 is designed to handle a powder material and the second screw conveyor 124’ is designed to handle a granular material. The first screw conveyor 124 and the second screw conveyor 124’ may be different, e.g. having different screw flights. Generally speaking, those for powder materials often feature a tighter pitch and a larger diameter compared to those for granules. This design variation can impact conveying efficiency and can prevent the bridging of fine powders, thereby ensuring smooth material flow without clogging or segregation. Additionally, the first screw conveyor 124 may include an agitation device or have a flexible screw design to enhance material flow and prevent clumping. For example, rotating paddles or vibratory devices may be positioned along the length of the first screw conveyor 124 to promote consistent material flow and prevent stagnation or bridging. By gently agitating the powder, the first screw conveyor 124 ensures uniform feeding and discharge, reducing the risk of blockages and improving process reliability. In contrast, the second screw conveyor 124’ has dual-axis auger design arranged in a helical configuration to facilitate efficient material movement while minimizing the risk of material buildup and blockages, ensuring smooth and uninterrupted operation screw conveyors for granules prioritize robustness and durability to accommodate the heavier and potentially abrasive nature of granular materials. The second screw conveyor 124’ may feature reinforced construction, larger diameter shafts, and abrasion-resistant coatings to withstand the challenges posed by granular materials.

[0073] In some embodiments, the weighing station 126 is intelligently programmed to control speed, providing accurate measurements and contributing to the overall efficiency of a polymer compounding process.

[0074] Sometimes there may be undesirable air emissions during material discharge. To address such issues, the material discharge unit 110 may include a vent.

[0075] With reference to FIG. 2D, the material discharge unit 110 includes two lines: a granular material line 218 and a powder material line 220. The granular material line 218 is configured to handle materials in a granular form, including a polymer in a granular form. The powder material line 220 is configured to handle materials in a powder form, including a nano- or micro-filler. As used herein, the term "nano-filler" refers to a filler wherein the filler is ground and / or sliced into size particles in the 1-500nm range. The term "micro-filler" refers to a filler wherein the filler is ground and / or sliced into size particles in the 500-2, OOOnm range.

[0076] The material discharge unit 110 includes a pneumatic conveying system, which is deployed to swiftly transport materials from the weighing station 126 to a mixing and drying unit 132. This pneumatic conveying system adds a layer of speed and accuracy, minimizing transfer times and optimizing the overall compounding workflow. The pneumatic conveying system includes an air mover like a suction (not shown), a feeder (not shown but would be downstream and being connected to valves 122, 128), a conveying line (not shown), a dust collector(not shown), and a vessel (descant dryer 134 and vacuum drying assisted ribbon blender 140) to collect the material at the endpoint. Motorized compressors and fans (not shown) at the beginning of the system, which generate the needed flow and pressure of air necessary to move material. Valves 122, 128 which prevent backflow of the compressed air in the system into the compressor area. Gauges and regulators (not shown) to check the PSI of the air inside the compressor, which are connected and operated via computer. A feeder system (not shown) that inserts the material to move into the conveyor without adding contaminants. Pipe (not shown) which serves as the line through which material is conveyed to an endpoint. Buffer tanks and vacuum loaders 138, which hold the compressed air and help to prevent irregular surges of airflow in the actuators, which are commonly cylinders and plungers. A material-gas separator (inside a vacuum loader 138) to separate the solid material from the air and deposit into the silos. Lump-breakers (inside a vacuum loader 138), which break down the lumps formed in the material to facilitate a continuous flow through the system with no blockages or build-up. Descant dryer 134 and vacuum drying assisted ribbonblender 140, serve as storage, which hold the material that is being moved, throughout the process whereby the material is separated from the gas.

[0077] The transport pipes of the pneumatic conveying system may be made from any suitable materials as long as the material would ensure the integrity of raw materials during transit. Stainless steel pipes with a frictionless coating have been selected over plastic alternatives, considering the abrasive nature of certain fillers. This decision enhances the durability of the system, mitigating the risk of pipe damage and ensuring a longer operational lifespan.

[0078] For the powder line, airlock valves 122 are used in the powder material line to control the material discharge flow and for the granular material line, pneumatic actuated reciprocating valves 128 are used.

[0079] With reference to FIGS. 3A-3D, a mixing and drying unit 132 is illustrated. The mixing and drying unit 132 includes a descant dryer 134 aiming to a granular material (such as hygroscopic biodegradable polymers) and a vacuum drying assisted ribbon blender 140 aiming to handle a powder material (such as nano- or micro-filler). The descant dryer 134 is operably connected to the pneumatic conveying system 128 and the vacuum drying assisted ribbon blender 140 is operably connected to a screw conveyor 160.

[0080] Some biodegradable polymers are known for their hygroscopic nature and as such, demand meticulous handling before processing. The descant dryer 134 is configured to handle such hygroscopic biodegradable polymers.

[0081] The descant dryer 134 is operably connected to the pneumatic conveying system and in operation, receives a granular material from the weighing station 126 via pneumatic conveying system. The descant dryer 134 may be a desiccant wheel dryer. In such embodiments, the desiccant wheel dryer may utilize pure molecular sieve desiccant grown onto a synthetic substrate. This substrate is rolled into a round shape and encased in stainless steel. As the wheel rotates, saturated air is pulled through the drying section, where moisture is adsorbed. The desiccated air is then heated to the required temperature and circulated back through the resin hopper. The cooling section prepares the desiccant for moisture adsorption, while the regeneration section involves heating ambient, filtered air and forcing it through the desiccant wheel, removing the adsorbed moisture. This continuous process provides a constant supply of dry desiccant, leading to increased efficiency, reduced power consumption.

[0082] The descant dryer 134 may include features, such as closed-loop cooling after regeneration and minimizing atmospheric moisture exposure during bed changeover.

[0083] To be energy efficient, the descant dryer 134 may include a dryer control system 136, which enables dewpoint monitoring with regeneration on demand function.

[0084] The descant dryer 134 may be a desiccant-rotor dryer, which is configured to offer continuous closed-loop drying.

[0085] The descant dryer 134 includes a mixing system therein, which may be a screw-type mixing system.

[0086] The descant dryer 134 includes a vacuum loader 138 having an integral motor that creates a vacuum to convey a granular material from a nearby pick up zone. The pickup of the granular material, including a polymer, is usually accomplished by an aluminum or stainless steel tube, called a pickup wand, which is connected to a relatively short piece of flex hose attached to the vacuum loader. A small electro-mechanical control, usually at the end of a pendant is set to manage load time, dump time and blowback.

[0087] The vacuum drying assisted ribbon blender 140 is used for drying a powder material, such as nano- or micro-filler, an additive, and other materials. In some embodiments, the vacuum drying assisted ribbon blender 140 is designed with vacuum-tight seals, aiming to facilitate efficient removal of volatile components at low temperatures and be suitable for heatsensitive materials. The vacuum process enabled by the vacuum drying assisted ribbon blender 140 can support solvent recovery and safe disposal of removed harmful materials. Customized seal arrangements, such as air-purged shaft seals, may be implemented to enhance protection against product leakage, extending wear parts' life.

[0088] In some embodiments, the vacuum drying assisted ribbon blender 140 includes a vacuum-assisted material cleanout system, enabling a thorough and automated removal of the polymer material. Once the batch mixing / blending is performed, the blender 140 utilizes a vacuum mechanism to extract material residues from the blender, eliminating the need for manual cleaning by operators.

[0089] The ribbon blender 140 may have a blade for mixing the powder material. The blade is configured to ensure a thorough and homogenous blend and may be used for a diverse range of powder formulations. The blade may be a rectangular wiper, configured to wipe the container surface during blending. The rectangular wiper aims to mitigate residue concerns and ensure a clean mixture, even in challenging clearance areas.

[0090] The ribbon blender 140 may includes a submicron filter coupled to the vacuum mechanism for efficient moisture removal without compromising small-sized particles mixture.

[0091] A heating jacket 146 may be used to facilitate the removal of moisture, volatiles, and air, elevating the overall quality of the blended powder material.

[0092] Dual temperature sensors, both internal and external, in conjunction with a real-time monitoring system driven by advanced algorithms, may be used to provide precise temperature control, adapting dynamically to the characteristics of different powder formulations.

[0093] In some embodiments, it would be desirable to have no void between valve seats, thereby simplifying assembly and disassembly. For example, rotary discharge valves 148 may be used to maintain a safe working environment. In some other embodiments, dust-tight knife gate valves may be used. The inventor found that dust-tight knife gate valves can be suitable for powders and dry materials and offer minimal dead space, ensuring optimal cleanability.

[0094] The ribbon blender 140 has a vacuum loader 142 with an integral motor 144 that creates a vacuum to convey the power material from a nearby pick up zone. The pickup of the powder material is usually accomplished by an aluminum or stainless steel tube, called a pickup wand, which is connected to a relatively short piece of flex hose attached to the vacuum loader. A small electro-mechanical control, usually at the end of a pendant is set to manage load time, dump time and blowback. It also has a filter that separates powder and air. It also has a heating jacket 146 which heats the powders inside and rotary valve discharge 148 help in discharging the material.

[0095] As better shown in FIG. 3C, after being processed by mixing and drying unit 132, the granular material is transferred to an auxiliary granular material storage hopper 162 and the powder material flows out from an outlet 158 and is transferred to an auxiliary powder storage hopper 163. Each one of the auxiliary granular material storage hopper 162 and the auxiliary powder storage hopper 163 may have a silo fluidizer 166 and a bin activator 164 to facilitate smooth material flow. The auxiliary granular material storage hopper 162 and the auxiliary powder storage hopper 163 store the dried and mixed materials for future use, e.g. for batch mixing. For example, when the granular material is polymer pellets, the polymer pellets in the auxiliary storage hopper 162 may be used to make a new batch of polymer, filler, and additive mixture.

[0096] In some embodiments, the bin activator 164 is designed to improve material flow control within a bulk handling system. The bin activator 164 can address common challenges such as bridging, rat-holing, and material stagnation through an adjustable vibrating cone. The discharge rates can be monitored and adjusted to promote a uniform material flow. The bin activator 164 includes an activation mechanism that is finely tuned and allows adaptable adjustments to discharge rates based on specific operational needs.

[0097] In some embodiments, the mixing and drying unit 132 includes sensors and is connected to the data acquisition and control system 130. When connected to the bin activator 164, the data in relation to it can offer real-time data on material levels and flow conditions, which enables the adaptive adjustments for enhanced reliability and efficiency.

[0098] in some embodiments, the auxiliary granular material storage hopper 162 and / or the auxiliary powder storage hopper 163 include a silo fluidizer 166 that includes a fluidization device that releases controlled bursts of compressed air into the stored material. The controlled bursts of compressed air help enable a uniform and consistent material flow, preventing stagnant regions. By adjusting the intensity and frequency of the compressed air bursts, the silo fluidizer 166 may work with various powder types and storage conditions, without compromising the material integrity.

[0099] The silo fluidizer 166 may be coupled with real-time sensors and the data acquisition and control system 130. Such real-time sensors can provide continuous data on material flow conditions, enabling adaptive adjustments for a reliable and efficient material-handling process.

[0100] In some embodiments, the mixing and drying unit 132 includes a moisture meter. The moisture meter is configured to detect the moisture level in the descant dryer 134 and / or the ribbon blender 140. The moisture meter is in communication with the controller 130. The moisture meter functions to generate and send signals the controller 130 and in response, the controller 130 generates and sends instructions to change the drying processing parameters, including drying speed, vacuum pressure, and mixing speed, so that the moisture level would return to a pre-determined moisture. In addition, the moisture level exceeds a predetermined limit, a re-drying protocol is initiated by the controller 130.

[0101] Also in relation to the moisture meter, in the realm of resin production, the drying process can play an important role, yet often create vulnerabilities susceptible to waste accumulation. Storing resin at a certain acceptable range of temperature levels and / or a certain moisture levels is important for industrial scale of resin production and finishedproducts. There is inherent variability inherent in drying processes, considering fluctuations in ambient moisture levels dictated by seasonal and plant conditions, alongside variations in production levels dictated by market demand. Failure to adapt the descant dryer 134 and / or the ribbon blender 140 to dynamic conditions can pose risks of under- or over-drying resin, resulting in material defects and escalated energy consumption.

[0102] In some embodiments, the inventor has tested and deployed a moisture meter capable of directly detecting resin moisture content, bypassing conventional air moisture measurements within the hopper. In one embodiment, the moisture meter uses electromagnetic waves and is configured to provide precise, real-time data on moisture levels. The moisture meter may be positioned before the inlet of the extrusion unit 214 so that unacceptable material, which does not comply with a pre-determined set of parameters, can be intercepted before it reaches the extrusion unit 214.

[0103] The moisture meter may be coupled to an automatic early-warning alarm so that operators can be promptly alerted to potential issues, mitigating adverse impacts on product quality.

[0104] To encourage uniform drying throughout the material, the inventor finds that it can be important to prevent the formation of uneven resin pockets caused by poor hopper flow. A proficiently designed dryer can address this concern by automatically adjusting airflow in response to production fluctuations, seamlessly transitioning from high to low throughput scenarios. User-friendly features further enhance operational efficiency, enabling input of material type and size to automate airflow adjustments, thereby optimizing resin transfer while safeguarding equipment integrity and product consistency.

[0105] The mixed and dried granular material is then transferred to a granular material feeder 156 and the mixed and dried powder material is then transferred to a powder material feeder 157. The granular material feeder 156, the powder material feeder 157, and other components, such as a liquid feeder 155, all of which are configured to feed materials into the extrusion unit 214, are collectively referred to as a dosing unit 168. The powder material feeder 157 may include a heating element and / or a mixing element to enable a chemical reaction between the dried and mixed powder material and the additive prior to feeding the mixture to the extrusion unit 214.

[0106] The granular material feeder 156 and the powder material feeder 157 may be gravimetric feeders, where precise feed rates are orchestrated for the extrusion unit 214 during compounding and extrusion. Feed rates can impact the compounding and extrusionprocess, which in term would impact the finished products. It is typically desirable to maintain consistent melt mixing and processing without disruptions or production inconsistencies. For example, in the continuous formulation of plastics, feed rate control can be important for achieving accurate proportioning of recipe components, such as resin and additives, prior to pelletization or end-product forming operations. In some embodiments, the granular material feeder 156 and the powder material feeder 157 each are programed to produce a controlled discharge rate tailored to the materials they handles respectively.

[0107] In some embodiments, the apparatus 100 may have more than the two feeders shown in FIGS. 3A-3D and the multiple feeders operate together. The multiple feeders may be monitored and programmed so that they automatically adjust their respective discharge rates to maintain desired recipe proportions, irrespective of the overall apparatus throughput.

[0108] Feed rate control can be expressed and managed either by volume (ft3 / hr or cm3 / min) or weight (Ib / min or kg / hr). In some embodiments, weight-based (gravimetric) feeding is deployed due to cost and quality considerations. Some attributes of the gravimetric concept include closed-loop control for direct measurement and control of feed rate, automatic compensation for material density variations, insensitivity to material build-up on metering elements within broad limits, direct measurement of material rate and throughput, high turndown with high linearity, automatic detection of material supply interruptions, and high- performance accuracy potential — all contributing to the efficiency and reliability of the compounding process.

[0109] In some embodiments, the granular material feeder 156 and the powder material feeder 157 are gravimetric feeders. A gravimetric feeder may include a dispensing screw that is engineered for the precise handling of both low and high-density powders. The gravimetric feeder may include an interior polytetrafluoroethylene (PTFE) liner to promote unobstructed material flow.

[0110] The granular material feeder 156 and the powder material feeder 157 may each be coupled with real-time sensors and the data acquisition and control system 130. Such realtime sensors can capture discharge rate data and in response to the discharge rate date, the apparatus 100 may deploy software algorithms and a closed-loop feedback system to dynamically adjust the dispensing screw speed. This adaptive control mechanism can promote a consistently accurate dispensing process, irrespective of powder density variations. A person skilled in the art would understand that the closed-loop feedback system is guided by predefined quality parameters (temperature, speed, pressure, SME, meltpressure, torque, feed rate, cooling speed, cutting speed, additive-filler ratio, density and more) that serve as benchmarks for the desired product characteristics. These parameters are established through comprehensive process analysis and quality control standards, defining the optimal conditions for producing high-quality biodegradable polymer composites. The closed-loop system continuously compares the real-time data against these predefined quality parameters, allowing for immediate corrective actions in the event of deviations. A gravimetric feeder can improve the precision and accuracy of dosing by measuring the weight of material dispensed in real-time up to 3 decimal points.

[0111] When gravimetric feeding is used, the gravimetric feeder relies on the force exerted by the material on a load cell, allowing for continuous monitoring and adjustment of the feed rate. The inventor found that gravimetric feeding can provide a high level of accuracy as it accounts for variations in material density, flow characteristics, and external factors. This gravimetric dosing approach helps achieve consistency in the delivered quantities. In this regard, the dosing unit 168 may allow dynamical adjustment of the feed rate to maintain the desired setpoint, offering precision even in the presence of fluctuations in material properties or process conditions.

[0112] In some embodiments, the dosing unit 168 is designed to achieve precise and tailored material dosing. The dosing unit 168 operates by utilizing a predetermined formulation, which includes specific proportions and characteristics of the materials to be dosed. In this context, the formulation serves as a comprehensive guide, detailing the precise composition and quantities of each component involved in the dosing process. The dosing unit 168 employs advanced control mechanisms, incorporating sensors, actuators, and processors, to dynamically adjust the dosing parameters based on real-time feedback and variations in material properties. By adhering to the predefined formulation, the dosing system ensures accuracy, consistency, and repeatability in the dosing process.

[0113] With reference to FIG. 4, the dosing unit 168 also includes a liquid feeder 155. The liquid is configured to add a liquid additive to the extrusion unit 214 via the powder material feeder 157. In some other embodiments, the liquid feeder 155 is configured to add a liquid additive to the extrusion unit 214 via a liquid injection nozzle 217.

[0114] With reference to FIGS. 4A-4D, the extrusion unit 214 is illustrated. The extrusion unit 214 is a screw-based extruder. The extrusion unit 214 is for twin-screw extrusion (TSE) compounding, which may handle a diverse array of materials, including pellets, granules, powders, fibers, and liquids. Instead of two screws, the extrusion unit 214 may include two ormore screws, wherein the screws interact with the mixture during the extrusion process. Such methods provide for a greater degree of mixing and otherwise manipulating the mixture to obtain the desired metal-organic compound. Of course, the extrusion unit 214 may be for single screw extrusion.

[0115] The granular material feeder 156 and the powder material feeder 157 each are connected to the extrusion unit 214 to feed materials to the extrusion unit 214. As discussed, granular material feeder 156, which may be volumetric feeders and Loss-in-Weight (LIW) feed streams, may be used to ensure accurate metering of multiple materials into the extrusion unit 214.

[0116] The pressure gradient within the extrusion unit 214 can be influenced by screw selection. In some embodiments, the pressure gradient may reach zero at specific stages, facilitating downstream material introduction through the powder material feeder 157, with liquids introduced via injection pumps.

[0117] In some embodiments, the extrusion unit 214 operates in a starve-fed mode, maintaining a partially filled process space between the screws 188 and the barrel 189. The output rate may be set by the granular material feeder 156, with screw rpm operating independently and in tandem to optimize compounding efficiencies. In some embodiments, residence time (RT) in the extrusion unit 214 is predominantly dictated by the feed rate, and the residence-time distribution (RTD) inherent to the extrusion unit 214 helps mitigate minor feeder fluctuations.

[0118] Even though the granular material feeder 156 and the powder material feeder 157 are named based on the physical form of the materials that they each handle. A person skilled in the art would understand that the granular material feeder 156 can be suitable for handling a powder material and that the powder material feeder 157 can be suitable for handling a granular material. The granular material feeder 156 and the powder material feeder 157 may be the same.

[0119] The inventor found that compounding biodegradable polymers sometimes presents challenges due to the polymers’ sensitivity to heat and shear, as well as susceptibility to hydrolytic degradation in the molten stage. To address these challenges, atmospheric vents 186, feeder vents 216, vacuum vents 187, and a vacuum system 212 connected to the vacuum vents 187 may be used to reduce maintenance and downtime, enhancing throughput rates.

[0120] When processing hygroscopic materials, the extrusion unit 214 may be operated in a way to maintain a low screw speed until torque or volumetric limits are met, thereby avoiding degradation risks associated with excessive heat and shear. FIG. 6 illustrates a design a screw 188. The design includes long, "gentle" mixing zones in the screw 188 to mitigate high torque, and stabilizing feeders minimizes torque fluctuations, enabling higher average torque operation. Depending on the conditions of shear and pressure and dwell time required during the extrusion process to obtain metal-organic compounds of the desired properties and yield, the configuration of the screw 188 or screws can be altered.

[0121] The inventor explored the efficiency of a co-rotating twin-screw extruder, noting its effectiveness as a mixing device but noting its limited efficiency as a pump. To address this, the extrusion unit 214 may include conveying screw elements with optimal pitch, and melt pumps with high pumping efficiencies between the extruder exit and the die to minimize melt temperature rise and ensure a stable extrudate flow. Where more intense mixing and application of shear and pressure are required, this can be achieved by using mixing elements, especially mixing paddles. Mixing paddles typically comprise lobed elements, e.g. elliptical or similar shaped elements, which do not comprise a helical thread. The paddles provided a curved flat mixing surface. In a twin screw extruder one or more corresponding pairs of lobed elements may be provided on each of the screws. The lobed element on one screw is arranged such that it is rotationally offset relative to the lobed element on the other screw, typically by 90° for bi-lobed (i.e. generally elliptical) paddles, such that when the elements rotate the mixing surfaces of the lobed elements are separated by a narrow gap, which may remain substantially constant during rotation due to the corresponding shapes of the pair of paddles, or might vary to some degree during rotation. Different degrees of offset may be used for tri-lobed, or other shapes of mixing elements as appropriate. The effect of such mixing paddles is that the mixture is smeared between the pair of paddles and is thus subjected to relatively intense mixing at high shear and pressure. In addition, the flat nature of the mixing surface means that forward conveyance is not strongly promoted and, as such, the mixture tends to dwell in such elements; forward conveyance of the mixture is primarily driven by pressure exerted by the upstream mixture being forced by upstream conveying elements, although, as discussed below, certain configurations of mixing elements can provide a degree of forward conveyance. The degree of mixing and application of shear and pressure can be determined by the number and configuration of mixing elements. Distributive mixing is a term well known in the art of extrusion and can be defined as “distributive mixingis the process of spreading a minor component throughout a matrix in order to achieve good spatial distribution”. Distributive mixing can be achieved by providing a sequence of pairs of mixing (e.g. lobed) elements, where each pair of mixing elements is rotationally offset relative to the preceding pair, i.e. at staggered angles. Generally subsequent mixing elements are offset in the same direction as the direction of the helical portion which provided forward conveyance. Typically the length of each mixing element (e.g. lobed element) will be up to 0.25* the diameter of the screw, preferably at least 0.125* the diameter of the screw; e.g. for a screw of diameter 16 mm, each element might have a length of 4 mm. Distributive mixing can be considered to be mixing predominantly by rearranging flow paths of the mixture of the substances; in essence the relative short length of each mixing element means that the mixture is churned between the mixing elements, and the level of highly constrained smearing is relatively low. The amount of rotational offset determines the amount of conveyance such a distributive mixing sequence provides, and to some extent the severity of the mixing. Where a pair is offset from the preceding pair by from around 10° to 45° (typically 30°) in the same direction as the helix on the feed screw, a significant degree of forward conveyance is provided; an offset of from around 46 to 65° (typically 60°) provides somewhat less conveyance; and an offset of from around 75° to 90° provided significantly less conveyance — an offset of 90° provides essentially no conveyance of the mixture.

[0122] Some biopolymers may be prone to rapid degradation. To address the related challenges, the extrusion unit 214 may enable preventative measures, including lowering barrel heats during extruder downtime, purging with a low-cost heat-stable polymer, and adhering to proper handling protocols before extrusion. In this regard, there is a level of free volume within the barrel 189, specifically tied to the outer diameter (OD) to inner diameter (ID) ratio of the screws 188. Different OD / ID ratios influence torque, shear rates, and mixing efficiency. The use of symmetrical splined screw shafts with a 1.55 OD / ID ratio may provide a balanced approach for torque and volume. In some other embodiments, the use of symmetrical splined screw shafts with a 1.66 / 1 OD / ID ratio, deeper flight depths, higher free volume, and increased torque, may provide a balanced approach for torque and volume. Biodegradable polymers, sensitive to heat and shear, pose challenges in TSE compounding.

[0123] The inventor found that the design of the extrusion unit 214 enables the lowering or turning off of barrel heats during extruder downtime, purging with a heat-stable polymer to avoid contamination, and careful selection of extruder metallurgy to withstand the corrosive nature of molten biopolymers, especially when compounded with abrasive fillers.

[0124] In some embodiments, the incorporation of fillers, depending on their aspect ratios, necessitates tailored processing parameters. In some embodiments, the extrusion unit 214 includes kneading-block elements with varying configurations to effectively distribute and disperse fillers in the polymer.

[0125] When processing low-bulk-density fillers, the inventor found that conveying efficiency can be increased increasing the coefficient of friction between the feed and barrel wall. To achieve this, a layer of feedstock material may be adhered to a porous barrel wall, thereby minimizing or eliminating wall slip.

[0126] The invention further explores the intricacies of the TSE compounding process, highlighting five distinct screw regions, each influencing mixing differently. To optimize the system for different materials, three types of screw designs are presented, each catering to specific filler / additive loadings.

[0127] In some embodiments, the extrusion unit 214 has a temperature control system for precise regulation of processing temperatures during polymer compounding. For example, the extrusion unit 214 may include a set of co-rotating intermeshing screws 188 housed within a temperature-controlled barrel 189. The temperature control system integrates multiple heating and cooling zones positioned along the barrel 189 to achieve a pre-determined thermal management. A combination of resistive heaters may be used to ensure accurate and uniform temperature distribution within each zone.

[0128] With reference to FIG. 4A, the temperature-controlled barrel 189 includes a feeding zone maintained at a first temperature, a compression zone maintained at a second temperature, a metering zone maintained at a third temperature, and a vacuum zone positioned above the metering zone and proximate the vents 186, 187. The feeder zone is where the granular material feeder 156 and the powder material feeder 157 are located. The granular material feeder 156 and the powder material feeder 157 feed the materials to the feeder zone of the temperature-controlled barrel 189. The compression zone is downstream of the feeder zone and is where melting and mixing activities take place. The metering zone is downstream of the compression zone and is where further mixing, dispersive, and distributive mixing activities take place. Vacuum zone is located on top of the metering zone and proximate the vacuum vent 187. The vacuum zone enables moisture and gas removal. The moisture may go through a condenser and the gas may go through a filter.

[0129] In some embodiments, the extrusion unit 214 incorporates may include sensors, feedback loops, and a control algorithm to dynamically adjust temperatures in response to variations in material properties, throughput rates, and ambient conditions.

[0130] In some embodiments, heat exchangers are positioned along the extruder barrel 189 to facilitate the transfer of thermal energy from the extruded material to a heat exchange medium. Additionally, regenerative braking mechanisms may be incorporated into the extrusion unit 214 to recover and convert kinetic energy generated during the process into reusable electrical energy. Band heater may be positioned outside of the barrel 189. The integration of energy recovery systems can improve overall energy efficiency of the twin- screw extrusion process, reducing operational costs and environmental impact.

[0131] In some embodiments, the extrusion unit 2014 includes a hybrid acid-resistance die plate to address the challenge arising from the presence of free acids that react with the die plate, leading to corrosion. The hybrid acid-resistance die plate help reduce downtime and off-specification pellets, enhancing operational efficiency and cost-effectiveness.

[0132] In some embodiments, sensors strategically are positioned along the extruder barrel 189 to capture data related to material properties, temperature, pressure, and other relevant parameters like torque, melt pressure, specific mechanical energy. These sensors interface with the central control unit 130, equipped with an algorithm that compares the real-time data against predefined quality benchmarks. In the event of deviations from the specified parameters, the closed-loop feedback system triggers immediate adjustments to the compounding process, ensuring that the final polymer product consistently meets the desired quality standards.

[0133] In a polymer extrusion process, the integration of sensors and monitoring devices for real-time data collection can provide comprehensive information about various extrusion parameters. These sensors capture data related to factors such as temperature, pressure, and material properties during the extrusion process. This real-time data is then fed into feedback algorithms, software designed to analyze the information and make continuous adjustments to extrusion parameters. The feedback algorithms act as the intelligence behind the closed-loop system, constantly evaluating the real-time data against predefined quality parameters. These quality parameters serve as benchmarks or standards that define the desired characteristics of the extruded product, such as its dimensions, mechanical properties, or surface finish. The closed-loop system, guided by these predefined quality parameters, makes instantaneous adjustments to the extrusion process to ensure that theoutput consistently meets the desired specifications. In essence, this closed-loop system creates a dynamic and adaptive extrusion process. The continuous monitoring and feedback loop allow for quick responses to variations or deviations from the set quality standards. This level of automation and precision not only enhances the overall efficiency of the extrusion process but also ensures a high level of consistency in the quality of the final extruded products.

[0134] A cooling unit 205 and a pelletizing unit 206 are better shown in FIGS. 6 and 6A. The cooling unit 205 and the pelletizing unit 206 together enable air pelletizing, where strands are cut immediately after leaving the nozzle plate, with air replacing water as the cooling and transport medium. The air cooling unit 205 consists of centrifugal blowers 200, conveyors 202, and a perforated steel belt 204. The inventor found that this approach is effective for cooling biodegradable polymer strands without water absorption or moisture-related issues.

[0135] The cooling unit 205 includes a vision monitoring system designed for extrusion processes. The vision monitoring system is programmed to capture images of the extruded polymer strands and analyze such images to assess the quality of the polymer strands. The vision monitoring system includes a high-resolution camera, which captures detailed images of the extruded polymer strands in real-time. Going beyond visual inspection, the vision monitoring system incorporates spectral analysis to detect subtle changes in the chemical and physical properties of the polymer strands. The vision monitoring system is also able to identify and quantify impurities of the extruded material. This may be done through spectral analysis, where the vision monitoring system discerns variations in the composition of the strands and provides insights into the presence and amount of contaminants. In the event of impurity detection, the system promptly sends a signal to alert an operator so that the operator can isolate and handle contaminated material, preventing downstream processing issues and ensuring product quality. In some other embodiments, the signal causes a fluid injector to spray a colour indicator to mark the identified potentially contaminated material.

[0136] The selection of the cooling and granulation process considers both the molten state and the solidified strand. Parameters such as melt stability, stickiness, brittleness, surface roughness, and heat capacity are taken into account. The coordination of process parameters ensures the fulfillment of critical criteria: uniform granulate shape, consistent size, smooth surface, low dust content, low residual moisture, and granulate temperature suitable for packaging (<40 °C).

[0137] The cooling unit 205 may include a chiller that utilizes the warm water generated from the compounding process as a heat source to boil refrigerant in the evaporator. The refrigerant is then compressed and sent to the condenser, where heat is removed using ambient air or water from a cooling tower system. In some embodiments, the chiller can dynamically adjust the pressure in the condenser, optimizing energy savings and providing stable refrigerant pressure control even under varying conditions.

[0138] Efficient and trouble-free conveying 202 is also relevant, necessitating careful consideration of pellet shape and size. Smooth granulate surfaces are prioritized to minimize conveying resistance and prevent water adhesion. Low residual moisture levels are targeted to facilitate further processing without the need for prior drying, while minimizing dust content is crucial for preserving conveyor technology and reducing maintenance costs.

[0139] Following the cooling and pelletizing process, the pellets may undergo a screening process utilizing a vibratory classifier 208. This screening operation results in the collection of uniform-sized pellets.

[0140] Also relevant to quality control is an inline quality testing and sorting mechanism system, which may employ computer vision technology, utilizing cameras and sensors to visually inspect the extruded polymer material. Laser spectroscopy is utilized for analyzing the material's spectral characteristics using a spectrometer 196. Upon detection of defects or non-conformities, the system may initiate an automated sorting process. The system's algorithms can categorize the identified material, allowing for efficient segregation without disrupting the continuous extrusion process. Detected deviations trigger immediate adjustments in compounding parameters, ensuring that corrective measures are applied promptly. The mechanism seamlessly integrates with downstream processing, automating the sorting of materials based on size, appearance, geometry, color etc. Laser spectroscopy may also be deployed at the material discharge unit 110 to assess and verify the quality of the raw materials.

[0141] With reference to FIGS. 7A-7D, a storage and packaging unit 184 is illustrated.

[0142] The storage and packaging unit 184 in some embodiments serves as a central repository for the compounded material, offering controlled and organized storage. From the storage and packaging unit 184, the compounded material may undergo a systematic transfer process into bags 182 and containers, marking the initiation of the packaging stage.

[0143] The illustrated storage and packaging unit 184 can be characterized as a storage silo system, engineered to preserve the integrity of raw materials by mitigating the impact ofmoisture and air. The storage and packaging unit 184 includes two silos 172. Each silo 172 includes a vacuum loader 170, facilitating efficient material transfer from the pelletizing unit 206 to the storage and packaging unit 184. The vacuum loader 170 helps ensure a contamination-free process. Each silo 172 is connected to a vacuum system 176 to effectively extract moisture and air from stored materials. The moisture and air removal process help prevent deterioration in material properties and preserve their inherent characteristics. Complementing the moisture removal mechanism, the silos 172 may each include a heater to maintain a consistent temperature within the silo, safeguarding materials against external environmental influences.

[0144] Sensors may be used in connection with the storage and packaging unit 184 to measure and monitor temperature and / or humidity. For example, temperature and humidity sensors may be used to provide real-time data to a storage controller 174 on the internal silo environment. The storage and packaging unit 184 is equipped to address the needs of hydrophilic and moisture-sensitive raw materials, offering a precise solution for industries requiring stringent environmental control.

[0145] The airlock valve 178 may be programmed to dispense material based on the user input and a weighing scale 180 with precision up to three digit after decimal point to accurately measure the weight.

[0146] Various packaging formats can implemented to accommodate different needs, including octabins, tote bags, and bag packs. In some embodiments, aluminum inner liners are used to address the high moisture sensitivity of biodegradable polymer granules. These liners can act as a protective barrier, preventing moisture ingress and safeguarding the quality of the compounded material.

[0147] To enhance preservation and extend the shelf life of the packaged materials, a vacuum sealing process may be employed. Vacuum sealing provides a secure and airtight enclosure, minimizing the risk of moisture intrusion and maintaining the integrity of the compounded materials during storage and transportation.

[0148] An intelligent inventory management system may be used. For example, RFID tags may be deployed in the silo / storage bin / mixer containing raw materials and additives with unique identification information. The RFID reader detects real-time tracking, capturing usage data and location of each item and ensure precise inventory control by sending the information to the central inventory management system and to the HMI panel which is operated by the engineer. Dynamic optimization algorithms used in this technologycontinuously analyze this real-time data, enabling the system to dynamically adjust inventory levels based on usage rates and anticipated requirements. This dynamic approach minimizes waste by aligning inventory levels precisely with the demands of the compounding process, fostering a continuous and efficient production flow. A blockchain system may be used to record each batch produced and verifies the entire production history. This includes data on raw material sourcing, compounding parameters, quality control measures, and defect rate.

[0149] In some embodiments, the powder raw material being fed into the apparatus 100 is a nano- or micro-hemp powder. The inventor has developed a powderization unit 222, which may be used to prepare a powder from fibrous plant materials, such as hemp, linen, ramine, jute, fax, and bamboo. The powderization unit 222 is shown in FIG. 8.

[0150] Using hemp as an example, the process of preparing a hemp powder from hemp stalks begins with the collection of hemp stalks, typically ranging from 3 to 6 feet in length, into a bulk sack.

[0151] The hemp stalks are then fed into a shredder 224, where the hemp stalks are shredded into hurds measuring between 2 to 6 inches in length.

[0152] As better shown in FIG. 9, the shredder 224 has a dual-shaft design, featuring two interlocking shafts 226 equipped with cutting blades 228. This design enables simultaneous shredding and tearing of materials from multiple angles, resulting in more efficient and thorough processing compared to single-shaft shredders.

[0153] The dual-shaft configuration enhances the shredding capacity and allows for the processing of tough and bulky item such as hemp stalks. The shredder 224 includes a drive control 230 which incorporates variable speed control mechanisms, offering operators greater flexibility and control over the shredding process. The drive control 230 allows an operator to adjust the rotational speed of the shredder shafts 226. This way, the operator can optimize performance based on the specific characteristics of the materials being processed, such as density, moisture content, and size. The drive control 230 can help enhance overall shredding efficiency and product quality while minimizing energy consumption and wear on the equipment.

[0154] The cutting blades 228 may have any suitable configurations. In the illustrated embodiment, the cutting blades 228 are serrated blades, which are suitable for shredding tough fibrous hemp stalks. In some other embodiments, the cutting blades 228 may be finetoothed blades, which are suitable for processing softer materials.

[0155] The shredder 224 may include safety features to protect an operator and prevent accidents during operation. These may include safety interlocks, emergency stop buttons, and overload protection systems that automatically shut down the shredder in the event of an overload or jam.

[0156] The shredder 224 may be equipped with sensors and be connected to the controller 130 to detect abnormalities in operation and alert an operator to potential hazards. These safety features enhance operator safety and contribute to a safer working environment.

[0157] The hurds are transported via an inclined cleated conveyor 232 to an ultrasonic bath 234 filled with water, where they are immersed for a duration of 5 minutes. This ultrasonic bath 234 serves to effectively clean any dirt present in the hurds. Ultrasonic waves are employed to create high-frequency vibrations in the cleaning solution, generating millions of tiny bubbles through a process known as cavitation. These bubbles implode upon contact with the surfaces of the hemp hurds, dislodging and removing darts, dirt, and contaminants without the need for abrasive scrubbing or harsh chemicals. This gentle yet highly effective cleaning method ensures thorough cleaning while minimizing damage to the hemp hurds, resulting in improved product quality.

[0158] Following the cleaning process, a solution of sodium hydroxide is applied within the ultrasonic bath 234 to eliminate any residual odors from the hurds. Sodium hydroxide, also known as caustic soda, is a powerful alkaline compound that is highly effective at neutralizing and eliminating odors caused by organic compounds and contaminants. When combined with the ultrasonic cleaning action, the sodium hydroxide solution penetrates deep into the pores of the hemp hurds, breaking down and neutralizing odor-causing molecules at their source. This innovative odor removal method ensures that the cleaned hemp hurds are free from unpleasant smells, enhancing their overall quality and marketability.

[0159] The inclined cleated conveyor 232 is employed to optimize space utilization and maximize material throughput. The cleated design of the conveyor belts provides enhanced grip and stability for the materials being transported. This ensures that even bulky or irregularly shaped items, such as hemp stalks, can be securely conveyed without slippage or loss of material. Additionally, the inclination of the conveyor aids in the smooth and continuous movement of materials, minimizing the risk of jams or blockages during transportation. The cleats on the conveyor belt prevent material from sliding back down the incline, allowing for a constant and efficient flow of materials between processing stations. This helps tostreamline production processes and improve overall efficiency by reducing downtime and maximizing output.

[0160] The cleaned hurds are then transferred via another inclined cleated conveyor 236 to a hammer milling machine 238, equipped with both steel chains and stainless steel sharp blades. Within the hammer milling machine, the chains deliver a hammering action while the blades execute cutting actions. This combination of hammering and cutting actions is essential for effectively reducing the particle size of the hurds. Given the relatively soft nature of most fibrous materials, the cutting action proves to be particularly efficient in achieving the desired reduction in particle size. Through this meticulous process, hemp stalks are successfully transformed into hemp powder, ready for use in a variety of applications.

[0161] As used herein, unless the context dictates otherwise, the terms “about” and “approximately” mean plus and minus 5%.

[0162] As used herein, unless the context dictates otherwise, the term “generally” and “substantially” mean in general terms. For example, a “generally rectangular cross section” means that a cross section has an overall shape of a rectangle, but it does not need to be perfectly rectangular.

[0163] Various features are described herein as being present in “some embodiments”. Such features are not mandatory and may not be present in all embodiments. Embodiments of the invention may include zero, any one or any combination of two or more of such features. All possible combinations of such features are contemplated by this disclosure even where such features are shown in different drawings and / or described in different sections or paragraphs. This is limited only to the extent that certain ones of such features are incompatible with other ones of such features in the sense that it would be impossible for a person of ordinary skill in the art to construct a practical embodiment that combines such incompatible features. Consequently, the description that “some embodiments” possess feature A and “some embodiments” possess feature B should be interpreted as an express indication that the inventors also contemplate embodiments which combine features A and B (unless the description states otherwise or features A and B are fundamentally incompatible).

[0164] While a number of exemplary aspects and embodiments have been discussed above, those of skill in the art will recognize certain modifications, permutations, additions and subcombinations thereof. It is therefore intended that the following appended claims and claims hereafter introduced are interpreted to include all such modifications, permutations, additionsand sub-combinations as are consistent with the broadest interpretation of the specification as a whole.

[0165] Some specific aspects include the following:A. An apparatus for manufacture of a biodegradable polymer composite, the apparatus comprising: a material discharge unit having a first discharging hopper, a second discharging hopper, and a mobile drive unit positioned above the first discharging hopper and the second discharging hopper, the mobile drive unit being configured to transport a first raw material and a second raw material to the first discharging hopper and the second discharging hopper, respectively; a mixing and drying unit comprising a descant dryer connected to the first discharging hopper by a first pneumatic conveying system and a vacuum drying assisted ribbon blender connected to the second discharging hopper by a second pneumatic conveying system, the descant dryer including a screw-type mixing system therein for mixing the first raw material and the vacuum drying assisted ribbon blender including a blade therein for mixing the second raw material; a dosing unit comprising a first feeder connected to the descant dryer for receiving the dried and mixed first raw material and a second feeder connected to the vacuum drying assisted ribbon blender for receiving the dried and mixed second raw material; and an extrusion unit connected to the dosing unit and for receiving and compounding the dried and mixed first raw material and the dried and mixed second raw material to extrude the biodegradable polymer composite.B. The apparatus of aspect A, further comprising: a first weighing station; a second weighing station; a first screw conveyor connecting the first discharging hopper and the first weighing station; and a second screw conveyor connecting the second discharging hopper and the second weighing station.C. The apparatus of aspect B, wherein the second screw conveyor has a screw flight that has a tighter pitch and a larger diameter than that of the first screw conveyor.D. The apparatus of any one of aspects A to C, further comprising a liquid feeder connected to the extrusion unit and configured to add a liquid additive to in the extrusion unit.D1. The apparatus of any one of aspects A to C, further comprising a liquid feeder connected to the extrusion unit and configured to add an additive to the dried and mixed first raw material and the dried and mixed second raw material in the extrusion unit.E. The apparatus of any one of aspects A to C, further comprising a liquid feeder being upstream of and connected to the second feeder and the liquid feeder being configured to add an additive to the dried and mixed second raw material in the second feeder.F. The apparatus of any one of aspects A to E, further comprising a controller and sensors in communication with the material discharge unit, the mixing and drying unit, the dosing unit and the extrusion unit via a network, wherein the controller provides a virtual apparatus in order to facilitate management of stock and flows of materials through the apparatus.G. The apparatus of aspect F, wherein: the controller and the sensors monitor discharge rates of the first feeder and the second feeder; the controller comprises a closed-loop feedback system to dynamically adjust the discharge rates to maintain a pre-determined recipe proportion.H. The apparatus of any one of aspects A to G, wherein the material discharge unit comprises an overhead crane system in which one or more crane assemblies positioned above the first discharging hopper and the second discharging hopper and the one or more crane assemblies are capable of moving within a network of wires or rails to a position suitable to discharge the first raw material and the second raw material to the first discharging hopper and the second discharging hopper, respectively.I. The apparatus of any one of aspects A to H, wherein the first discharging hopper and / or the second discharging hopper has a wedge-shaped hopper with a generally rectangular cross-section and curved edges.J. The apparatus of any one of aspects A to H, wherein the first discharging hopper and / or the second discharging hopper is coated with an antistick formulation and / or an antistatic formulation.K. The apparatus of any one of aspects A to H, wherein the first discharging hopper and / or the second discharging hopper has a silo fluidizer.L. The apparatus of any one of aspects A to L, wherein the mixing and drying unit comprises: a first auxiliary storage hopper being downstream of and connected to the descant dryer and for receiving the mixed first raw material; and a second auxiliary storage being downstream of and connected to the vacuum drying assisted ribbon blender and for receiving the mixed second raw material.M. The apparatus of aspect L, wherein the first auxiliary storage hopper and / or the second auxiliary storage has a silo fluidizer and a bin activator.N. The apparatus of aspect L, wherein the first auxiliary storage hopper and / or the second auxiliary storage is a gravimetric feeder.O. The apparatus of aspect N, wherein the gravimetric feeder has an interior polytetrafluoroethylene (PTFE) liner.P. The apparatus of any one of aspects A to O, wherein the first feeder and / or the second feeder is a volumetric feeder or a loss-in-weight feed stream.Q. The apparatus of any one of aspects A to P, wherein the extrusion unit includes an atmospheric vents, a liquid injection nozzle, a vacuum vent, and a vacuum system connected to the vacuum vent.R. The apparatus of any one of aspects A to Q, wherein the extrusion unit comprises a twin-screw extruder.S. The apparatus of aspect R, wherein: the twin-screw extruder has a temperature-controlled barrel, including a feeding zone maintained at a first temperature, a compression zone maintained at a second temperature, a metering zone maintained at a third temperature, and a vacuum zone; the first feeder and the second feeder feed the first mixed and dried raw material and the second mixed and dried raw material to the feeding zone; the compression zone is downstream of the feeding zone and is where the first mixed and dried raw material and the second mixed and dried raw material are mixed and melted; the metering zone is downstream of the compression zone and is where further mixing, dispersive, and distributive mixing activities take place; and the vacuum zoom is positioned above the metering zone and facilitate moisture and gas removal from the temperature-controlled barrel.T. The apparatus of aspect S, wherein the temperature-controlled barrel comprises kneading-block elements in the metering zone.U. The apparatus of aspect S, wherein the twin-screw extruder includes heat exchangers positioned along temperature-controlled barrel to facilitate the transfer of thermal energy from the extruded biodegradable polymer composite to a heat exchange medium.V. The apparatus of aspect S, wherein the twin-screw extruder includes a regenerative braking mechanism to recover and convert kinetic energy generated from the extruded biodegradable polymer composite into reusable electrical energy.W. The apparatus of aspect S, wherein the twin-screw extruder includes a band heater positioned outside of the temperature-controlled barrel.X. The apparatus of any aspects of A to W, further comprising: an air cooling unit;a pelletizing unit; and a storage and packaging unit.Y. The apparatus of any aspects of A to W, further comprising an air cooling unit and a vision monitoring system programmed to capture images of the extruded biodegradable polymer composite and analyze the images to assess the quality of the extruded biodegradable polymer composite.Z. The apparatus of aspect Y, wherein the vision monitoring system is programed to conduct spectral analysis to detect a change in the chemical and physical properties of the extruded biodegradable polymer composite.AA. The apparatus of aspect Z, wherein if the detected change exceeds a pre-determined range, the vision monitoring system generates a signal to alert an operator of the change.BB. The apparatus of aspect A, further comprising an inline quality testing and sorting mechanism system.CC. The apparatus of aspect BB, wherein the inline quality testing and sorting mechanism system includes cameras and sensors to visually inspect the extruded biodegradable polymer composite.DD. The aspect of aspect CC, wherein the inline quality testing and sorting mechanism system includes a spectrometer for analyzing spectral characteristics of the extruded biodegradable polymer composite.EE. The aspect of aspect DD, wherein if the inline quality testing and sorting mechanism system determines a change in the spectral characteristics that is beyond a pre-determined range, the inline quality testing and sorting mechanism system initiates a sorting process to isolate the extruded biodegradable polymer composite associated with the change.FF. The apparatus of any aspects of A to W, further comprising:a pelletizing unit being downstream of and connected to the extrusion unit, wherein the pelletizing unit receives the extruded biodegradable polymer composite and processes the biodegradable polymer composite into pellets; and a storage and packaging unit including multiple silos and each silo including a vacuum loader, facilitating material transfer from the pelletizing unit to the silo.GG. A bulk material handling system for twin screw extrusion compounding of biodegradable polymer composites, including: an automated raw material handling system with sensors and machine learning algorithms for precise measurement and dispensing of biodegradable polymer pellets and additives; real-time quality control sensors integrated throughout the upstream process to monitor average particle size, moisture content, and polymer bulk density; integration of screw conveyors and pneumatic conveying systems for efficient transfer of powdered or granular biodegradable polymers within the process line; and a modular design enabling the handling of various bulk materials with diverse physical and chemical properties.HH. A bulk material loading system fortwin screw extrusion compounding of biodegradable polymers, including: mobile bulk truck loading systems for loading dry bulk solids into transport vehicles; stockpile loading systems for efficient loading of bulk materials from stockpiles; and tanker loading systems, hopper loading systems, and big bag loading systems for loading various containers with precise control.II. A bulk material storage system for twin screw extrusion compounding of biodegradable polymers, including: silos, hoppers, and bins for safe and compact storage of powdered and granular dry bulk materials; storage systems designed to minimize ground space consumption, prevent bulk material contamination, and optimize flow into downstream systems; and bulk solid storage systems adaptable to store large and small volumes of dry solids with a focus on flexibility and efficiency.JJ. A bulk material discharge system for twin screw extrusion compounding of biodegradable polymers, including: a silo discharge system, mixer discharge systems, and tank discharge systems for stimulating or improving dry solids flow; discharge systems influencing downstream equipment design to ensure optimal processing; and various discharge systems, including big bag discharge, octabin discharge, bag dump, bulk truck unloading, tanker unloading, and storage hopper discharge.KK. A bulk material dosing system for twin screw extrusion compounding of biodegradable polymers, including: gravimetric or volumetric dosing systems for precise and accurate dosing of bulk materials; integration of pneumatic conveying systems to feed bulk material mixers; and formulation-based dosing systems that consider the properties of bulk solids for achieving accurate and consistent outputs.LL. An integrated twin screw extruder system for biodegradable polymer composites, including: an in-line additive injection system for precise incorporation of reinforcing agents, fillers, or colorants; a twin screw extruder with enhanced mixing capabilities for thorough dispersion of additives and uniform distribution of materials; and an advanced temperature control system for preventing thermal degradation and ensuring consistent processing temperatures.MM. A downstream processing and automation system for twin screw extrusion compounding of biodegradable polymer composites, including: downstream processing units with automation features for pelletizing and cooling; energy recovery systems, such as heat exchangers and regenerative braking mechanisms, to capture and reuse excess heat; anda closed-loop feedback system for continuous monitoring and adjustments based on predefined quality parameters.NN. An intelligent inventory management system for twin screw extrusion compounding of biodegradable polymer composites, including:RFID technology for real-time tracking of raw material and consumable usage; dynamic optimization algorithms for material procurement, minimizing waste and ensuring continuous production flow; and integration with the upstream process for seamless formulation adjustments.OO. An inline quality testing and sorting mechanism for twin screw extrusion compounding of biodegradable polymer composites, including: computer vision and spectroscopy for identifying and segregating defective or nonconforming material; real-time data feedback to upstream processes for immediate adjustments; and integration with downstream processing for automated sorting.PP. A customizable formulation control interface for twin screw extrusion compounding of biodegradable polymer composites, including: user-friendly interface allowing operators to input and modify material formulations; customization features for adjusting process parameters and production schedules; and compatibility with different formulations, facilitating adaptability to changing market demands.QQ. A remote monitoring and control system for twin screw extrusion compounding of biodegradable polymer composites, including: secure access for operators to monitor and manage the extrusion process remotely; real-time data visualization and analytics for process performance assessment; and two-way communication for making real-time adjustments and troubleshooting.RR. A blockchain traceability system for twin screw extrusion compounding of biodegradable polymer composites, including:integration of blockchain technology to record and verify the entire production history of each batch; transparency in the supply chain, providing end-users with information about material origins and characteristics; and verification of sustainable sourcing practices through immutable and transparent records.SS. An energy-efficient twin screw extrusion compounding system for biodegradable polymer composites, including: real-time energy monitoring systems to track energy consumption at various stages; implementation of energy recovery systems, including heat exchangers and regenerative braking mechanisms; and integration of energy-efficient technologies or renewable energy sources to power the extrusion process.TT. A closed-loop feedback system for continuous process optimization in twin screw extrusion compounding of biodegradable polymer composites, including: sensors and monitoring devices for real-time data collection; feedback algorithms that analyze data and make continuous adjustments to extrusion parameters; and predefined quality parameters to guide the closed-loop system in maintaining product consistency.UU. A fully automated material-handling system for compounding biodegradable polymers, including: a central-chiller control system utilizing innovative technology to continuously calculate the lowest allowable refrigerant pressure under varying load and condenser inlet temperatures, optimizing energy savings and providing stable refrigerant pressure control.VV. An apparatus for drying biodegradable polymer materials, including desiccant-wheel dryers with air-to-air after-cooling options, enabling self-contained operation without a water connection; anda sensor-driven control system adjusting drying parameters based on reliable inline moisture measurements.WW. A fully automated material-handling system for blending biodegradable polymers, Including: a self-cleaning blender with a vacuum-assisted material cleanout system; facilitating a complete material change without operator assistance; and enabling material removal to a collection station or bin.XX. A dust-removal system for processing dry granular material in biodegradable polymer compounding, including: temperature-tolerant features; an integrated level sensor; and variable-speed paddles for precise control of solids feed rate, improving maintenance and operational efficiency.YY. An air cooling unit for biodegradable polymer compounding, comprising: an air-cooled metal screen conveying belt; and air-conditioned blowing fans to expedite the cooling process for hygroscopic polymers.ZZ. A vibration-actuated classifier incorporated into the compounding process to effectively separate granules based on size classification, enhancing the overall efficiency of polymer compounding.AAA. Screw designs tailored for the effective processing of heat-sensitive, shear-sensitive, and moisture-sensitive polymers in the compounding process, ensuring optimal polymer quality and processing efficiency.BBB. Direct-charge blender loading systems designed specifically for the direct-charge loading of blenders in biodegradable polymer compounding, including: integrated power sources; filters; controls; and blender covers to streamline the loading process.CCC. Ergonomic bag-dump stations with negative pressure systems for loading biodegradable polymer materials, comprising: reducing spillage; fugitive dust; and safety risks during bag loading in the compounding process.DDD. A free-flowing screw discharger designed to handle sticky powders in the compounding process, comprising: efficient material discharge; and preventing operational challenges associated with adhesive polymer properties.100 apparatus for manufacture of biodegradable polymer composites110 material discharge unit112 mobile drive unit114 pillars with hooks116 bulk bags118 discharging hopper120 load sensors122 airlock valve124 screw conveyor126 weighing station128 pneumatic actuated reciprocating valve130 data acquisition and control system132 mixing and drying unit134 descant dryer136 dryer control system138 vacuum loader140 vacuum drying assisted ribbon blender142 vacuum loader144 integral motor146 heating jacket148 rotary valve discharge150 overhead crane system152 one or more crane assemblies154 wires or rails155 liquid feeder156 granular material feeder157 powder material feeder158 outlet160 screw conveyor162 auxiliary granule storage hopper163 auxiliary powder storage hopper164 bin activator166 silo fluidizer168 dosing unit170 vacuum loader172 storage silo or silo174 storage controller176 vacuum system178 airlock valve180 weighing scale182 bags184 storage and packaging unit186 atmospheric vents187 vacuum vents188 screw196 spectrometer200 centrifugal blowers202 conveyors204 perforated steel belt205 cooling unit206 pelletizing unit208 vibratory classifier212 vacuum system214 an extrusion unit216 feed vents217 liquid injection nozzle218 granular material line220 powder material line222 powderization unit224 shredder226 interlocking shafts228 cutting blades 230 drive control232 inclined cleated conveyor234 ultrasonic bath236 another inclined cleated conveyor238 hammer milling machine

Claims

WHAT IS CLAIMED IS:1 . An apparatus for manufacture of a biodegradable polymer composite, the apparatus comprising: a material discharge unit having a first discharging hopper, a second discharging hopper, and a mobile drive unit positioned above the first discharging hopper and the second discharging hopper, the mobile drive unit being configured to transport a first raw material and a second raw material to the first discharging hopper and the second discharging hopper, respectively; a mixing and drying unit comprising a descant dryer connected to the first discharging hopper by a first pneumatic conveying system and a vacuum drying assisted ribbon blender connected to the second discharging hopper by a second pneumatic conveying system, the descant dryer including a screw-type mixing system therein for mixing the first raw material and the vacuum drying assisted ribbon blender including a blade therein for mixing the second raw material; a dosing unit comprising a first feeder connected to the descant dryer for receiving the dried and mixed first raw material and a second feeder connected to the vacuum drying assisted ribbon blender for receiving the dried and mixed second raw material; an extrusion unit connected to the dosing unit and for receiving and compounding the dried and mixed first raw material and the dried and mixed second raw material to extrude the biodegradable polymer composite; and a controller and sensors in communication with the material discharge unit, the mixing and drying unit, the dosing unit and the extrusion unit via a network, wherein the controller provides a virtual apparatus in order to facilitate management of stock and flows of materials through the apparatus.

2. The apparatus of claim 1 , wherein: the material discharge unit comprises an overhead crane system in which one or more crane assemblies positioned above the first discharging hopper and the second discharging hopper and the one or more crane assemblies are capable of moving within a network of wires or rails to a position suitable to discharge the first raw material and the second raw material to the first discharging hopper and the second discharging hopper, respectively; and the overhead crane system is in communication with the controller and the sensors;the controller and the sensors monitor discharge rates of the first discharging hopper and the second discharging hopper; the controller comprises a closed-loop feedback system to dynamically adjust the discharge rates to maintain a pre-determined recipe proportion.

3. The apparatus of claim 1 , wherein: the controller and the sensors monitor discharge rates of the first feeder and the second feeder; and the controller comprises a closed-loop feedback system to dynamically adjust the discharge rates to maintain a pre-determined recipe proportion.

4. The apparatus of any one of claims 1 to 3, further comprising: a first weighing station; a second weighing station; a first screw conveyor connecting the first discharging hopper and the first weighing station; and a second screw conveyor connecting the second discharging hopper and the second weighing station; wherein the second screw conveyor has a screw flight that has a tighter pitch and a larger diameter than that of the first screw conveyor.

5. The apparatus of any one of claims 1 to 4, wherein the first discharge hopper and / or the second discharge hopper has a wedge-shaped hopper with a generally rectangular crosssection and curved edges, is coated with an antistick formulation and / or an anti-static formulation, and / or has a silo fluidizer.

6. The apparatus of any one of claims 1 to 5, further comprising a liquid feeder connected to the extrusion unit and configured to add an additive to the dried and mixed first raw material and the dried and mixed second raw material in the extrusion unit.

7. The apparatus of any one of claims 1 to 5, further comprising a liquid feeder being upstream of and connected to the second feeder and the liquid feeder being configured to add an additive to the dried and mixed second raw material in the second feeder, wherein thesecond feeder includes a heating element and / or a mixing element to enable a chemical reaction between the additive to the dried and mixed second raw material in the second feeder.

8. The apparatus of any one of claims 1 to 7, wherein: the extrusion unit comprises a twin-screw extruder; the twin-screw extruder has a temperature-controlled barrel, including a feeding zone maintained at a first temperature, a compression zone maintained at a second temperature, a metering zone maintained at a third temperature, and a vacuum zone; the first feeder and the second feeder feed the first mixed and dried raw material and the second mixed and dried raw material to the feeding zone; the compression zone is downstream of the feeding zone and is where the first mixed and dried raw material and the second mixed and dried raw material are mixed and melted; the metering zone is downstream of the compression zone and is where further mixing, dispersive, and distributive mixing activities take place; and the vacuum zoom is positioned above the metering zone and facilitate moisture and gas removal from the temperature-controlled barrel.

9. The apparatus of claim 8, wherein the twin-screw extruder includes heat exchangers positioned along temperature-controlled barrel to facilitate the transfer of thermal energy from the extruded biodegradable polymer composite to a heat exchange medium, a regenerative braking mechanism to recover and convert kinetic energy generated from the extruded biodegradable polymer composite into reusable electrical energy, and / or a band heater positioned outside of the temperature-controlled barrel.

10. The apparatus of any one of claims 1 to 9, further comprising an air cooling unit and a vision monitoring system programmed to capture images of the extruded biodegradable polymer composite and analyze the images to assess the quality of the extruded biodegradable polymer composite.

11. The apparatus of claim 10, wherein the vision monitoring system is programed to conduct spectral analysis to detect a change in the chemical and physical properties of the extruded biodegradable polymer composite, wherein if the detected change exceeds a pre-determined range, the vision monitoring system generates a signal to alert an operator of the change.

12. The apparatus of any one of claims 1 to 9, further comprising an inline quality testing and sorting mechanism system, wherein the inline quality testing and sorting mechanism system includes cameras and sensors to visually inspect the extruded biodegradable polymer composite.

13. The apparatus of claim 12, wherein the inline quality testing and sorting mechanism system includes a spectrometer for analyzing spectral characteristics of the extruded biodegradable polymer composite.

14. The apparatus of claim 13, wherein if the inline quality testing and sorting mechanism system determines a change in the spectral characteristics that is beyond a pre-determined range, the inline quality testing and sorting mechanism system initiates a sorting process to isolate the extruded biodegradable polymer composite associated with the change.

15. The apparatus of claim 1 , further comprising: an air cooling unit being downstream of the extrusion unit, the air cooling unit for receiving and air cooling the extruded biodegradable polymer composite; a pelletizing unit being downstream of the air cooling unit, wherein the pelletizing unit receives the air cooled extruded biodegradable polymer composite and processes the biodegradable polymer composite into pellets; and a storage and packaging unit including multiple silos and each silo including a vacuum loader, facilitating material transfer from the pelletizing unit to the silo.

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