Production apparatus and production method of pellet

Abstract

To provide a production apparatus and a production method of pellets capable of stably and efficiently producing pellets having a food byproduct or the like as the raw material and desired property.SOLUTION: A production apparatus of pellets for producing pellets from a raw material containing a food byproduct includes: a granulating device 32 for forming pellets by pressing the raw material; a feeder 30 for sending the raw material to the granulating device 32; a feeder motor 31 for rotating and driving the feeder 30; and a control device 10 for controlling driving of the feeder motor 31. The granulating device 32 has a die 36 formed with through holes 37 where pellets are formed, a compressing roller 33 for rolling and press-fitting the raw material into the through holes 37, and a main motor 34 for rotating and driving the compressing roller 33. The control device 10 has a current sensor 35 for detecting a current value of the main motor 34 and controls a rotation frequency of the feeder motor 31 based on the current value of the main motor 34 detected by the current sensor 35.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method for producing pellets using food by-products and the like as raw materials, and to a pellet production apparatus for producing the pellets. [Background technology]

[0002] It has been known to produce pellets for fuel, etc., using woody biomass as a raw material. For example, Patent Document 1 discloses a pellet manufacturing device that crushes and compresses biomass material to produce pellets. The pellet manufacturing device disclosed in the document includes a box having an inlet for biomass material at the top and an outlet for pellets at the bottom, a die that is provided to separate the internal space of the box into upper and lower parts and has a group of holes made of a large number of through holes that penetrate from the top to the bottom, and a push roller that is disposed above the die and rolls over the group of holes to crush the biomass material introduced from the inlet between the die and the die, and also compresses it while pushing it through each of the through holes to produce pellets.

[0003] Also, for example, Patent Document 2 discloses an extrusion molding machine for producing wood pellets. The extrusion molding machine disclosed in this document has a single-shaft screw connected to a motor and rotatable, a cylinder with the screw housed horizontally inside, a raw material supply port for supplying raw wood material provided at the top near the rear end of the cylinder, and a die provided at the tip of the cylinder with multiple extrusion holes formed therein.

[0004] Also, for example, Patent Document 3 discloses a method for producing fuel pellets, which includes a drying step of drying woody biomass and factory residue, a mixing step of mixing the dried woody biomass with the factory residue to produce a mixed fuel, and a pelletizing step of extruding the mixed fuel to form fuel pellets. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2018-144341 A [Patent Document 2] JP 2013-940 A [Patent Document 3] JP 2019-172766 A Summary of the Invention [Problem to be solved by the invention]

[0006] The conventional pellet manufacturing method has a problem in that it is not easy to stably maintain the quality of the produced pellets. Specifically, when food by-products and wood biomass are used as raw materials for pellets, the quality of the pellets varies greatly depending on the type, composition, moisture content, mixing ratio, etc. of the food by-products and wood used as raw materials for the pellets.

[0007] Therefore, in pellet production, in order to produce pellets with the desired properties, it was necessary to appropriately adjust the mixing ratio of the raw materials, the dryness, temperature, the pressing force of the granulation device, etc. depending on the type of food by-products, etc. that are used as the raw materials for the pellets.

[0008] The above adjustments in pellet production are performed by skilled workers who adjust the feeder motors that feed each raw material at each process, the heaters that heat each raw material, the main motor that drives the compression rollers of the granulation device, etc. according to the condition of the raw materials, and are not an easy task.

[0009] In response to this, Patent Document 3 discloses a method for producing fuel pellets with desired properties. Specifically, the fuel pellet production method disclosed in this document includes an adjustment process for analyzing the properties of the molded fuel pellets and adjusting at least one of the mixing ratio of at least one of sludge and factory residue to woody biomass in the mixing process, the drying time and drying temperature in the drying process, and the extrusion pressure of the mixed fuel in the pelletizing process so that the properties fall within a preset threshold value.

[0010] However, even with such adjustment processes of the conventional technology, in order to obtain pellets with the desired properties, adjustments to the feeder motor, main motor, etc., must be made by a skilled worker, and it has not been easy to efficiently produce pellets of excellent quality in a stable manner.

[0011] The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide a pellet manufacturing apparatus and a pellet manufacturing method that can stably and efficiently produce pellets with desired properties using food by-products and the like as raw materials. [Means for solving the problem]

[0012] The pellet manufacturing apparatus of the present invention is a pellet manufacturing apparatus that produces pellets from raw materials including food by-products, and is equipped with a granulating device that presses the raw materials to form the pellets, a feeder that sends the raw materials to the granulating device, a feeder motor that rotates and drives the feeder, and a control device that controls the drive of the feeder motor, wherein the granulating device has a die having a through hole through which the raw materials are pressed and the pellets are formed, a compression roller that rolls to press the raw materials into the through hole, and a main motor that rotates and drives the compression roller, and the control device has a current sensor that detects the current value of the main motor, and controls the rotation speed of the feeder motor based on the current value of the main motor detected by the current sensor.

[0013] Moreover, the pellet manufacturing method of the present invention is a method for manufacturing pellets from raw materials including food by-products, and is characterized in that the pellets are manufactured using the pellet manufacturing apparatus described above. Effect of the Invention

[0014] The pellet manufacturing apparatus of the present invention is a pellet manufacturing apparatus for manufacturing pellets from raw materials including food by-products, and includes a pelletizer for pressing the raw materials to form the pellets, a feeder for feeding the raw materials to the pelletizer, a feeder motor for rotating the feeder, and a control device for controlling the drive of the feeder motor. The pelletizer includes a die having a through hole in which the raw materials are pressed to form the pellets, a compression roller for rolling to press the raw materials into the through hole, and a main motor for rotating the compression roller. The control device includes a current sensor for detecting the current value of the main motor, and controls the number of revolutions of the feeder motor based on the current value of the main motor detected by the current sensor. This allows the pressing of the raw materials by the compression roller to be automatically adjusted, and pellets with desired properties can be stably and efficiently manufactured using food by-products and the like as raw materials. This allows the productivity of pellets manufactured from raw materials including food by-products to be increased.

[0015] According to the pellet manufacturing apparatus of the present invention, the pelletizer has a hydraulic mechanism that applies a pressing force to the compression roller to press the raw material against the die, and the control device has a hydraulic sensor that detects the hydraulic pressure of the hydraulic mechanism and controls the rotation speed of the feeder motor based on the hydraulic pressure of the hydraulic mechanism detected by the hydraulic sensor. This makes it possible to automatically control the feed rate of the raw material more appropriately and efficiently produce high-quality pellets.

[0016] According to the pellet manufacturing apparatus of the present invention, the control device may control the feeder motor to reduce its rotation speed when the hydraulic pressure of the hydraulic mechanism detected by the hydraulic pressure sensor exceeds a predetermined value. By controlling in this way, the pressure on the raw material can be maintained at an appropriate level, and pellets with appropriate properties can be stably manufactured.

[0017] The pellet manufacturing apparatus of the present invention may further include a conveyor that sends the pellets formed by the pelletizing apparatus to a packaging apparatus, and the control device may have a pellet temperature sensor that detects the temperature of the pellets sent by the conveyor and control the number of revolutions of the feeder motor based on the temperature of the pellets detected by the pellet temperature sensor. By such control, the pellets can be molded in an optimal state and pellets with optimal properties can be stably manufactured.

[0018] According to the pellet manufacturing apparatus of the present invention, the conveyor is provided with a heating means for heating the pellets and a cooling means for cooling the pellets, and the control device may have a moisture sensor for detecting the moisture content of the pellets conveyed by the conveyor, and control the output of the heating means and the cooling means based on the moisture content of the pellets detected by the moisture sensor and the temperature of the pellets detected by the pellet temperature sensor. This allows the pellets formed by the pelletizing device to be dried and the moisture content of the pellets to be automatically adjusted in an appropriate manner. Therefore, pellets with appropriate properties can be stably and efficiently manufactured by automatic control.

[0019] The pellet manufacturing apparatus of the present invention may further comprise a plurality of tanks each containing a plurality of types of raw materials including at least one food by-product, a plurality of raw material feeders for sending the raw materials contained in the tanks to a path connected to the pelletizing apparatus, and a plurality of raw material feeder motors for rotating the raw material feeders, and the control device may control the drive of the raw material feeder motors so that the raw material mixing ratio becomes a predetermined value. This allows the raw material mixing ratio to be automatically adjusted appropriately, and high-quality pellets to be efficiently manufactured.

[0020] The pellet manufacturing method of the present invention is a method for manufacturing pellets from raw materials including food by-products, and the pellets are manufactured using the pellet manufacturing apparatus of the present invention. This makes it possible to stably and efficiently manufacture pellets with desired properties using food by-products and the like as raw materials.

[0021] In addition, in the pellet manufacturing method of the present invention, the raw material contains 5 to 10% of the food by-product and 90 to 95% of woody biomass, and the pellets may be fuel. This makes it possible to efficiently manufacture environmentally friendly, high-quality pellets that effectively utilize woody biomass and food by-products. [Brief description of the drawings]

[0022] [Figure 1] 1 is a diagram showing a schematic configuration of a pellet manufacturing apparatus according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a diagram showing a schematic configuration of a control device of the pellet manufacturing apparatus according to the embodiment of the present invention. [Diagram 3] FIG. 2 is a flow diagram showing a pellet manufacturing process of the pellet manufacturing apparatus according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A pellet manufacturing apparatus and a pellet manufacturing method according to an embodiment of the present invention will be described in detail below with reference to the drawings. Fig. 1 is a diagram showing a schematic configuration of a pellet manufacturing apparatus 1 according to an embodiment of the present invention. Referring to Fig. 1, the pellet manufacturing apparatus 1 is an apparatus for manufacturing pellets from raw materials including food by-products such as snack foods. Food by-products are food or raw material residues generated during the production of commercial foods in food manufacturing factories, restaurants, etc., and waste from unsold food products.

[0024] The pellet manufacturing apparatus 1 may also be used as an apparatus for manufacturing pellets from raw materials including food by-products and wood-based biomass such as wood and wood chips. The pellets manufactured by the pellet manufacturing apparatus 1 are used as fuel, fertilizer, etc.

[0025] The pellet manufacturing apparatus 1 comprises a raw material tank 13, a foreign matter removal device 16, a crushing device 20, a mixing device 24, an intermediate hopper 29, a granulating device 32, a heating device 42, a cooling device 45 and a weighing and packaging device 48, which are connected in the order of pellet processing steps.

[0026] The raw material tank 13 is a tank in which the raw material pellets are charged and stored. A hopper (not shown) is formed in the raw material tank 13, and the raw material pellets are charged into the raw material tank 13 through the hopper and stored therein.

[0027] A plurality of raw material tanks 13 are provided so that different types of raw materials can be stored in the respective separate raw material tanks 13. Specifically, for example, four raw material tanks 13, i.e., raw material tanks 13a, 13b, 13c, and 13d, may be provided. Each of raw material tanks 13a, 13b, 13c, and 13d can store different types of raw materials.

[0028] The raw material tank 13 and the foreign matter removal device 16 are connected so as to be capable of transporting raw materials. A raw material feeder 14 for feeding raw materials is provided on a path connecting the raw material tank 13 to the foreign matter removal device 16.

[0029] The raw material feeder 14 is, for example, a screw feeder that rotates about a rotation axis that is coaxial with the piping that feeds the raw materials and feeds the raw materials in the direction of the rotation axis. A raw material feeder motor 15 that rotates the raw material feeder 14 is connected to the raw material feeder 14 directly or via a power transmission mechanism (not shown).

[0030] The raw material feeders 14 are provided for the raw material tanks 13a, 13b, 13c, and 13d in which different kinds of raw materials are stored separately. That is, the path connecting the raw material feeders 14 and the foreign matter remover 16 is provided with a plurality of raw material feeders 14 capable of separately feeding different kinds of raw materials, for example, four raw material feeders 14a, 14b, 14c, and 14d. This allows the mixing ratio of the different kinds of raw materials to be suitably controlled.

[0031] The foreign matter remover 16 is a device that roughly crushes the raw materials transported from the raw material feeder 14 and removes magnetic foreign matter by magnetic force. The foreign matter remover 16 is provided with a foreign matter removal motor 17 that rotates a crushing tool or the like that roughly crushes the raw materials.

[0032] The foreign matter removal device 16 can remove impurities such as iron contained in the raw materials, and can prevent the crushing device 20, mixing device 24, etc. used in the subsequent processes from being damaged by impurities such as iron. In addition, impurities such as iron can be prevented from being contained in the pellets, and safety can be ensured when the pellets are used as fertilizer, etc.

[0033] The outlet of the foreign matter remover 16 is connected to a path that sends the raw material from which the foreign matter has been removed to a crusher 20. The path that connects the foreign matter remover 16 to the crusher 20 is provided with a foreign matter removed raw material feeder 18 that sends the raw material.

[0034] The foreign matter removed raw material feeder 18 is, for example, a screw feeder. A foreign matter removed raw material feeder motor 19 that rotates the foreign matter removed raw material feeder 18 is connected to the foreign matter removed raw material feeder 18 directly or via a power transmission mechanism (not shown).

[0035] The crushing device 20 is a device that crushes the raw materials transported from the foreign matter removal device 16 into pieces of a size suitable for pellet molding. The crushing device 20 is provided with a crushing tool that crushes the raw materials into a predetermined size while rotating, and a crushing motor 21 that rotates and drives the crushing tool. This allows the raw materials to be crushed into a size suitable for pellet molding.

[0036] The grinding device 20 is connected to the mixer 24 via a path capable of transporting the ground raw materials. The path connecting the grinding device 20 and the mixer 24 is provided with a ground raw material feeder 22 for feeding the raw materials.

[0037] The pulverized raw material feeder 22 is, for example, a screw feeder. A pulverized raw material feeder motor 23 that rotates the pulverized raw material feeder 22 is connected to the pulverized raw material feeder 22 directly or via a power transmission mechanism (not shown).

[0038] The raw material processing steps by the foreign matter remover 16 and the crusher 20 may be performed by batch processing. That is, the different kinds of raw materials sent from the respective raw material feeders 14a, 14b, 14c, and 14d may be subjected to the steps of coarse crushing, foreign matter removal, and crushing by batch processing for each raw material, and then sent to the mixer 24.

[0039] Furthermore, the raw material processing steps by the foreign matter remover 16 and the crusher 20 may be configured so that different kinds of raw materials sent from the respective raw material feeders 14a, 14b, 14c, and 14d are simultaneously processed.

[0040] The mixer 24 is a device that mixes a plurality of different raw materials fed into a plurality of raw material feeders 14 and transported via the foreign matter remover 16 and the grinder 20. The mixer 24 is provided with an agitator having a stirring motor 25 and a stirring blade that is driven to rotate by the stirring motor 25. The different raw materials are mixed by the stirring blade that is driven to rotate by the stirring motor 25.

[0041] An intermediate hopper 29 for temporarily storing the mixed pellet raw material is connected to the mixer 24. A mixed raw material feeder 27 for feeding the raw material mixed in the mixer 24 is provided in the path connecting the mixer 24 and the intermediate hopper 29.

[0042] The mixed raw material feeder 27 is, for example, a screw feeder. A mixed raw material feeder motor 28 that rotates the mixed raw material feeder 27 is connected to the mixed raw material feeder 27 directly or via a power transmission mechanism (not shown).

[0043] The foreign matter removal device 16, the crushing device 20, and the mixing device 24 may be configured as a single device. In other words, the processes of coarse crushing of raw materials, removal of foreign matter, crushing, and mixing may all be performed by a single device, for example, continuously.

[0044] A granulator 32 is connected to the outlet of the intermediate hopper 29. A feeder 30 that sends the raw material stored in the intermediate hopper 29 to the granulator 32 is provided in a path connecting the intermediate hopper 29 and the granulator 32.

[0045] The feeder 30 is, for example, a screw feeder. A feeder motor 31 that rotates the feeder 30 is connected to the feeder 30 directly or via a power transmission mechanism (not shown).

[0046] The granulating device 32 is a dry granulating device that presses the raw material fed by the feeder 30 to form pellets. Specifically, the granulating device 32 has a die 36 having a through hole 37 formed therein into which the raw material is pressed to form pellets, a compression roller 33 that rolls to press the raw material into the through hole 37, and a main motor 34 that drives the compression roller 33 to rotate.

[0047] The die 36 is, for example, disk-shaped, and has a large number of through holes 37 through which the raw material passes while being pressed into and formed into pellets. The die 36 is disposed, for example, substantially horizontally so as to divide the inside of the granulating device 32 into an area where the raw material is introduced and an area where the pellets are extruded.

[0048] The compression rollers 33 are rolling rollers that press the raw material against the die 36, and a plurality of them are provided, for example, above the die 36. The compression rollers 33 roll on the upper surface of the die 36 around their rolling axes that extend horizontally, i.e., approximately parallel to the upper surface of the die 36, while rotating around a central axis that extends vertically, i.e., a rotation axis that is located at approximately the same position as the center of the die 36.

[0049] The granulator 32 is provided with a main motor 34 that rotates and drives the compression roller 33. The granulator 32 is also provided with a hydraulic mechanism 38 that applies a pressing force to the compression roller 33 to press the raw material against the die 36. The hydraulic mechanism 38 uses hydraulic pressure to press the compression roller 33 against the die 36 with a predetermined force.

[0050] A conveyor 40 having, for example, a conveyor motor 41 is connected to the granulator 32 as a conveying means for conveying the produced pellets to a weighing and packaging device 48. The conveyor 40 may be provided with a heating device 42 for heating the produced pellets and a cooling device 45 for cooling the produced pellets.

[0051] The heating device 42 is a heating device having, as a heating means, for example, a heater 43. The cooling device 45 is a cooling device having, as a cooling means, for example, a blower 46 for blowing air. The blower 46 is a cooling fan that blows air to the pellets to cool them.

[0052] The heater 43 of the heating device 42 heats the pellets or the air blown onto the pellets, evaporating excess moisture contained in the pellets and drying the pellets. In addition, the blower 46 of the cooling device 45 blows cold air onto the pellets, so that the pellets from which moisture has been removed by the heating device 42 can be cooled to a temperature suitable for the next packaging process. In other words, pellets with excellent properties can be sent to the weighing and packaging device 48 at a stable and appropriate temperature.

[0053] The weighing and packaging device 48 is a device that weighs and packages the produced pellets. The weighing and packaging device 48 is provided with a pellet weighing sensor 49 that weighs the pellets, various other sensors (not shown) that detect the quality of the pellets, and a packaging means (not shown) that automatically packs a predetermined amount of pellets into bags. The packaging means may be, for example, an industrial robot.

[0054] Fig. 2 is a diagram showing a schematic configuration of a control device 10 of the pellet manufacturing apparatus 1. With reference to Figs. 1 and 2, the pellet manufacturing apparatus 1 has the control device 10 that automatically controls a feeder motor 31 and various other driving mechanisms that constitute the pellet manufacturing apparatus 1.

[0055] The control device 10 is an arithmetic processing device that includes a microprocessor and executes predetermined arithmetic operations. Specifically, the control device 10 includes a central processing unit (CPU), a read-only memory (ROM), a random access memory (RAM), and the like.

[0056] The control device 10 has an input unit 11 through which a user inputs various information such as pellet processing conditions, ON / OFF and other commands, and a display unit 12 that displays various measurement values, the state of the processing process, the processing schedule, error information, etc. The input unit 11 and the display unit 12 are connected to the main body of the control device 10 by wire or wirelessly so as to be able to communicate information. The input unit 11 and the display unit 12 may be, for example, an information communication terminal or the like.

[0057] Various detection sensors are connected to the control device 10. For example, a temperature sensor 26, a current sensor 35, an oil pressure sensor 39, a moisture sensor 44, a pellet temperature sensor 47, a pellet weighing sensor 49, an air temperature sensor (not shown), a humidity sensor (not shown), an air pressure sensor (not shown), an image sensor (not shown), and other sensors (not shown) are connected to the control device 10 by wire or wireless so as to be able to communicate information.

[0058] The temperature sensor 26 is provided in the mixer 24 to detect the temperature of the raw materials mixed in the mixer 24 and sent to the granulator 32. The temperature sensor 26 may be provided in the intermediate hopper 29 to detect the temperature of the raw materials in the intermediate hopper 29. The temperature sensor 26 may also be provided in other piping routes so as to detect the temperature of the raw materials.

[0059] The current sensor 35 is provided in the main motor 34 of the granulator 32 and is a sensor that detects a current value of the main motor 34. Although details will be described later, the control device 10 performs a predetermined calculation based on the current value of the main motor 34 detected by the current sensor 35 to inverter-control the rotation speed of the feeder motor 31.

[0060] The hydraulic sensor 39 is provided in the hydraulic mechanism 38 of the granulator 32 and detects the hydraulic pressure of the hydraulic mechanism 38, i.e., the hydraulic pressure applied to the hydraulic mechanism 38 to press the die 36 and transmitted to the main motor 34. The control device 10 performs a predetermined calculation based on the hydraulic pressure detected by the hydraulic sensor 39 and uses it to control the rotation speed of the feeder motor 31.

[0061] The moisture sensor 44 is a sensor that detects the moisture content of the pellets produced by the mixer 24, and is provided on the conveyor 40 or the like downstream of the mixer 24. The moisture sensor 44 may also be provided on the heating device 42 or on the conveyor 40 or the like upstream of the heating device 42.

[0062] The pellet temperature sensor 47 is a sensor that detects the temperature of the pellets produced in the mixer 24. The pellet temperature sensor 47 is provided, for example, on the conveyor 40 downstream of the mixer 24. The pellet temperature sensor 47 may also be provided on the cooling device 45 or on the conveyor 40 upstream of the cooling device 45.

[0063] As described above, the pellet weighing sensor 49 is a sensor that measures the weight of the pellets, and is provided in the weighing and packaging device 48. The weighing and packaging device 48 may also be provided with other inspection sensors (not shown) and connected to the control device 10 so as to be capable of communicating information with the control device 10.

[0064] In addition, various devices to be controlled by the control device 10 are connected to the control device 10. For example, raw material feeder motors 15a, 15b, 15c, and 15d, foreign body removal motor 17, foreign body removed raw material feeder motor 19, grinding motor 21, ground raw material feeder motor 23, stirring motor 25, mixed raw material feeder motor 28, feeder motor 31, main motor 34, hydraulic mechanism 38, conveyor motor 41, heater 43, blower 46, packaging means (not shown) of weighing and packaging device 48, and the like are connected to the control device 10 via wire or wireless so as to be able to communicate information.

[0065] The control device 10 executes a predetermined calculation based on various detection values ​​such as the current value of the main motor 34, the hydraulic pressure of the hydraulic mechanism 38, the raw material, the pellets, etc., detected by the various sensors mentioned above, and controls the feeder motor 31 and various other controlled devices. Such highly efficient automatic control allows for stable, automated, and highly productive pellet production.

[0066] The control device 10 may also be configured to control each of the controlled devices using machine learning based on artificial intelligence, i.e., AI (Artificial Intelligence). That is, the control device 10 may store and learn the detection values ​​from various sensors and the properties of the pellets produced to recognize a control pattern, and appropriately control the operation of each of the controlled devices according to the learned control pattern. As a result, in pellet production, the control of the advanced production process that was conventionally performed by skilled workers can be automated using AI technology, and stable, high-quality pellets can be produced stably and efficiently.

[0067] Next, the pellet manufacturing method using the pellet manufacturing apparatus 1 will be described in detail with reference to FIGS. Fig. 3 is a flow diagram showing the pellet manufacturing process of the pellet manufacturing apparatus 1. As shown in Fig. 3, the pellet manufacturing process sequentially includes a raw material supplying process P1, a crushing process P2, a mixing process P3, a raw material sending process P4, a granulating process P5, a drying process P6, and a weighing and packaging process P7.

[0068] 1 to 3, first, in a raw material supplying step P1, raw materials in the form of pellets are fed into a raw material tank 13 via a hopper (not shown). At least one of the raw materials is a food by-product, such as a snack food recovered from food manufacturing, that contains fats and oils, for example, potato chips, corn fries, fried ramen, fried rice crackers, etc.

[0069] When food by-products containing fats and oils, such as the above-mentioned potato chips, are used as raw materials, the fats and oils in the raw materials may be separated from the solids by a screw compression type solid-liquid separator such as an expeller (not shown), and mainly only the solids from which the fats and oils have been removed may be charged into raw material tank 13 as the raw material for producing pellets.

[0070] The raw materials may be, for example, food waste generated from restaurants and other food products, school lunches, etc., or food waste that has been fermented in advance. The raw materials may be, for example, wood-based biomass such as wood, wood chips, branches, bark, etc. The raw materials may also be other waste that can be used as a raw material for fertilizer or fuel, etc. These raw materials are separated by type and stored in the corresponding raw material tanks 13.

[0071] As described above, a plurality of raw material tanks 13 are provided so that different kinds of raw materials can be stored separately. For example, one raw material tank 13a may store food by-products such as potato chips, and another raw material tank 13b may store other food by-products such as corn fries. Also, for example, one raw material tank 13a may store wood-based biomass raw materials such as wood, and the other raw material tanks 13b, 13c, 13d, etc. may store food by-products. This makes it possible to produce pellets of fertilizer, fuel, etc. with suitable properties by suitably mixing different kinds of raw materials.

[0072] Next, in the raw material supply process P1, each raw material supplied to the raw material tank 13 is sent by the raw material feeder 14 to the foreign matter removal device 16. The sending of the raw materials by the raw material feeder 14 is executed under the control of the control device 10.

[0073] Specifically, the control device 10 controls a raw material feeder motor 15, which rotates the raw material feeder 14, at a predetermined rotation speed by controlling an inverter (not shown). This enables the raw material feeder 14 to supply a predetermined amount of each raw material to the foreign matter remover 16 at a predetermined feed speed.

[0074] Here, each of the raw material feeders 14a, 14b, 14c, and 14d that feed different kinds of raw materials is controlled so that the raw material mixing ratio becomes a predetermined value. That is, each of the raw material feeder motors 15a, 15b, 15c, and 15d that drive each of the raw material feeders 14a, 14b, 14c, and 14d is inverter-controlled by the control device 10, and rotates the raw material feeders 14a, 14b, 14c, and 14d at a predetermined rotation speed. This allows the raw material mixing ratio to be automatically adjusted appropriately, and high-quality pellets to be efficiently manufactured.

[0075] For example, when pellets are produced as fuel, the raw materials to be formed into pellets preferably contain 5-10% food by-products and 90-95% woody biomass. This makes it possible to efficiently produce high-quality pellets that are environmentally friendly, have a suitable hardness, and have excellent combustion performance by effectively using woody biomass and food by-products. The control device 10 can appropriately control the rotation speed of the raw material feeder motor 15 to adjust the supply of each raw material to achieve the above-mentioned suitable mixing ratio.

[0076] Furthermore, the process of sending each raw material from the raw material tank 13 to the foreign matter remover 16 in the raw material supply process P1 described above, or the process of sending each raw material to the mixer 24 via the foreign matter remover 16 and the crusher 20 performing the crushing process P2 described below, may be performed as a batch process. Furthermore, the process of sending each of these different raw materials may be performed continuously or simultaneously. Regardless of the control method, each raw material can be accurately sent in an appropriate amount by automatic control by the control device 10.

[0077] Next, the pulverization process P2 is carried out. Specifically, the raw material is roughly pulverized in the foreign matter removal device 16, and foreign matter such as iron is removed by a magnet, and the raw material is pulverized in the pulverizer 20 to a size suitable for producing pellets.

[0078] The control device 10 controls the drive of the foreign matter removal motor 17 of the foreign matter removal device 16, the foreign matter removal raw material feeder 18 that sends raw materials from the foreign matter removal device 16 to the grinding device 20, the grinding motor 21 of the grinding device 20, and the grinding raw material feeder motor 23 that sends raw materials from the grinding device 20 to the mixer 24.

[0079] At this time, the control device 10 executes a predetermined calculation based on a predetermined control target value that has been set in advance, the current value of the main motor 34 detected by the current sensor 35, the temperature of the raw material detected by the temperature sensor 26, and various detection values ​​detected by other sensors not shown, to perform the above-mentioned controls.

[0080] The control of the foreign object removal motor 17, foreign object removal material feeder 18, pulverization motor 21 and pulverization material feeder motor 23 by the control device 10 may be only ON / OFF control with a constant rotation speed.

[0081] In the mixing step P3, the raw materials from which foreign matter has been removed and which have been pulverized in the pulverization step P2 are mixed in the mixer 24. The raw materials mixed in the mixer 24 are then transported by the mixed raw material feeder 27 to the intermediate hopper 29, where they are temporarily stored.

[0082] The control device 10 controls the driving of the agitator motor 25 and the mixed raw material feeder motor 28 based on the current value of the main motor 34 detected by the current sensor 35, the temperature of the raw materials detected by the temperature sensor 26, etc. The control of the agitator motor 25 and the mixed raw material feeder motor 28 may be only ON / OFF control with a constant frequency.

[0083] The raw material feeding process P4 is a process of feeding the pellet raw material mixed in the mixer 24 in the mixing process P3 and stored in the intermediate hopper 29 to the granulator 32. Specifically, the pellet raw material is fed to the granulator 32 by the feeder 30 and thrown above the die 36.

[0084] The control device 10 performs a predetermined calculation based on a current value of the main motor 34 detected by a current sensor 35 in addition to a preset control target value, and thereby performs inverter control of the rotation speed of the feeder motor 31 .

[0085] That is, the control device 10 performs inverter-type multi-stage control or proportional control on the feeder motor 31 to be controlled, using the current value of the main motor 34 as a control variable. This allows the pressure of the raw material by the compression roller 33 to be suitably and automatically adjusted, and pellets with desired properties can be stably and efficiently produced using food by-products and the like as raw materials. This increases the productivity of pellets produced from raw materials containing food by-products.

[0086] Furthermore, the control device 10 may perform calculations based on the hydraulic pressure of the hydraulic mechanism 38 detected by the hydraulic pressure sensor 39 in addition to the current value of the main motor 34 detected by the current sensor 35, and may inverter-control the rotation speed of the feeder motor 31. This allows the amount of raw material fed to be more suitably and automatically controlled, enabling efficient production of high-quality pellets.

[0087] Specifically, the control device 10 may basically perform control based on the current value of the main motor 34 detected by the current sensor 35, and may also perform control to reduce the rotation speed of the feeder motor 31 when the hydraulic pressure of the hydraulic mechanism 38 detected by the hydraulic sensor 39 exceeds a predetermined value. By such control, the pressing of the raw material can be maintained in an appropriate state, and pellets with appropriate properties can be stably produced.

[0088] The control device 10 may inverter-control the rotation speed of the feeder motor 31 based on the temperature of the pellets produced and transported by the conveyor 40, detected by the pellet temperature sensor 47. That is, the control device 10 may perform a predetermined calculation based on the current value of the main motor 34 detected by the current sensor 35 and the temperature of the pellets detected by the pellet temperature sensor 47, and inverter-control the rotation speed of the feeder motor 31 that feeds the raw materials to the granulator 32. By such control, the pellets can be molded in an optimal state in the granulator 32, and pellets with optimal properties can be stably produced.

[0089] Next, in the granulation step P5, pellets are formed from the raw material sent to the granulation device 32 in the raw material sending step P4. Specifically, the raw material is pressed by the rolling of the compression roller 33 and forced into the through hole 37 of the die 36. Then, the raw material passes through the through hole 37 to generate pellets, and the generated pellets are extruded from the through hole 37.

[0090] In the granulation step P5, the control device 10 drives and controls the main motor 34. In this embodiment, the rotation speed of the feeder motor 31 is controlled by the control device 10, so that pellets having desired properties can be produced. Therefore, the control of the main motor 34 by the control device 10 may be only ON / OFF control with the rotation speed kept constant.

[0091] In the granulation process P5, a pressing force is applied to the compression roller 33 by the hydraulic mechanism 38 to press the die 36. The pressing force by the hydraulic mechanism 38 may be controlled by the control device 10 based on the value of the hydraulic pressure detected by the hydraulic pressure sensor 39.

[0092] After the pellets are produced in the granulation process P5, a drying process P6 is performed. The pellets produced in the granulation device 32 are transported to a weighing and packaging device 48 by a conveyor 40. The pellets are dried by a heating device 42 and a cooling device 45 provided on the transport path.

[0093] Specifically, the pellets are heated directly by heater 43 of heating device 42 or by using air blown by an air blower (not shown). This allows excess moisture in the pellets to evaporate and the pellets to be dried. The dried pellets are then cooled to a suitable temperature for packaging by air blown by blower 46 of cooling device 45.

[0094] The conveying speed of the conveyor motor 41, the amount of heat of the heater 43, the amount of air blown by the blower 46, and the like in the drying process P6 are controlled by the control device 10. Specifically, the control device 10 may execute a predetermined calculation based on the moisture content of the pellets detected by the moisture sensor 44 and the temperature of the pellets detected by the pellet temperature sensor 47 to control the outputs of the conveyor motor 41, the heater 43, and the blower 46. This makes it possible to dry the pellets formed by the pelletizing device 32 and automatically adjust the moisture content of the pellets in an appropriate manner. Therefore, pellets with appropriate properties can be stably and efficiently produced by automatic control.

[0095] The weighing and packaging process P7 is a process in which the produced pellets are weighed, quality inspected, automatically packaged, etc. The weighing and packaging process P7 is performed by the weighing and packaging device 48 based on the control of the control device 10.

[0096] Specifically, after the quality of the pellets is inspected using an inspection device such as an image recognition inspection device (not shown), the pellets are weighed by a pellet weighing sensor 49 and a predetermined amount of pellets are stored and packaged in a packaging container. In this way, a pellet product for use as fuel or fertilizer is completed. Each process of conveying, inspecting, packaging, etc. of the pellets may be performed by an industrial robot (not shown) controlled by the control device 10.

[0097] As described above, according to the pellet manufacturing apparatus 1 of this embodiment, high-quality pellets can be produced stably and efficiently through automatic control by the control device 10, and the productivity of pellets, which previously required many adjustments in the manufacturing process, can be significantly improved.

[0098] The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit and scope of the present invention. [Explanation of symbols]

[0099] 1: Pellet manufacturing equipment 10: Control device 11: Input section 12:Display section 13, 13a, 13b, 13c, 13d: Raw material tank 14, 14a, 14b, 14c, 14d: Raw material feeder 15, 15a, 15b, 15c, 15d: Raw material feeder motor 16: Foreign matter removal device 17: Foreign object removal motor 18: Foreign matter removal raw material feeder 19: Foreign object removal raw material feeder motor 20: Crushing equipment 21: Grinding motor 22: Crushed raw material feeder 23: Grinding material feeder motor 24: Mixing device 25: Stirring motor 26: Temperature sensor 27: Mixed raw material feeder 28: Mixed material feeder motor 29: Intermediate hopper 30: Feeder 31: Feeder motor 32: Granulation equipment 33: Compression roller 34: Main motor 35: Current sensor 36: Dice 37:Through hole 38: Hydraulic mechanism 39: Oil pressure sensor 40: Conveyor 41: Conveyor motor 42: Heating device 43: Heater 44: Moisture sensor 45: Cooling device 46: Blower 47: Pellet temperature sensor 48:Measuring and packaging equipment 49: Pellet weighing sensor P1: Raw material supply process P2: Crushing process P3: Mixing process P4: Raw material feeding process P5: Granulation process P6:Drying process P7: Weighing and packaging process

Claims

1. A pellet manufacturing apparatus for manufacturing pellets from raw materials including food by-products, A pelletizer that presses the raw material to form the pellets; A feeder for feeding the raw material to the granulation device; A feeder motor that rotates the feeder; A control device that controls the drive of the feeder motor, The granulation device includes a die having a through hole into which the raw material is pressed to form the pellets, a compression roller that rolls to press the raw material into the through hole, and a main motor that rotates and drives the compression roller, The control device has a current sensor that detects a current value of the main motor, and controls the rotation speed of the feeder motor based on the current value of the main motor detected by the current sensor.

2. The granulating device has a hydraulic mechanism that applies a pressing force to the compression roller to press the raw material against the die, 2. The pellet manufacturing apparatus according to claim 1, wherein the control device has a hydraulic sensor that detects the hydraulic pressure of the hydraulic mechanism, and controls the rotation speed of the feeder motor based on the hydraulic pressure of the hydraulic mechanism detected by the hydraulic sensor.

3. 3. The pellet manufacturing apparatus according to claim 2, wherein the control device controls the feeder motor to reduce a rotation speed when the hydraulic pressure of the hydraulic mechanism detected by the hydraulic pressure sensor exceeds a predetermined value.

4. A conveyor is provided for sending the pellets formed by the granulator to a packaging device. The pellet manufacturing apparatus according to claim 1, characterized in that the control device has a pellet temperature sensor that detects the temperature of the pellets fed by the conveyor, and controls the rotation speed of the feeder motor based on the temperature of the pellets detected by the pellet temperature sensor.

5. The conveyor is provided with a heating means for heating the pellets and a cooling means for cooling the pellets, The pellet manufacturing apparatus described in claim 4, characterized in that the control device has a moisture sensor that detects the moisture content of the pellets transported by the conveyor, and controls the output of the heating means and the cooling means based on the moisture content of the pellets detected by the moisture sensor and the temperature of the pellets detected by the pellet temperature sensor.

6. a plurality of tanks each storing a plurality of types of raw materials, at least one of which includes a food by-product; A plurality of raw material feeders that feed the raw materials stored in the tank to a path leading to the granulator; a plurality of raw material feeder motors each for rotating the raw material feeders; 2. The pellet manufacturing apparatus according to claim 1, wherein the control device controls the drive of the raw material feeder motor so that the mixing ratio of the raw materials becomes a predetermined value.

7. 1. A method for producing pellets from a feedstock comprising a food by-product, comprising: A method for producing pellets, comprising the steps of: producing the pellets by using the pellet production apparatus according to any one of claims 1 to 6.

8. The raw material contains 5 to 10% of the food by-products and 90 to 95% of wood-based biomass; The method of claim 7, wherein the pellets are fuel.

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