Drier

Abstract

To reduce an oil content contained in an object to be dried after a drying process.SOLUTION: A groove 58 for flowing oil and an auxiliary discharge port 62 are provided around a bottom plate 54 of a drying chamber 18. Since the oil oozing from an object to be dried during the drying process is discharged from the auxiliary discharge port 62, an oil content of the object to be dried after the drying process is reduced, and when the object to be dried is used as livestock feed or the like, an oil-squeezing treatment can be eliminated or alleviated. When the object to be dried charged into the drying chamber 18 contains a large amount of moisture, the auxiliary discharge port 62 is kept closed immediately after the start of the drying process to prevent the object to be dried from flowing out.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a drying device that heats and dries materials to be dried, such as food residue, to change them from a muddy state to a lump state, and then to discharge them in the form of granules or fine powder. [Background technology]

[0002] The present inventors have developed and put into practical use an apparatus that dries materials to be dried, such as food waste, and turns them into granules or fine powder, which are then reused as fertilizer, livestock feed, etc. (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4282551 Summary of the Invention [Problem to be solved by the invention]

[0004] If the ingredients of the material to be dried do not contain a large amount of salt or fat, the dried granular or fine powder obtained by this device can be shipped as livestock feed as is. However, if the powder obtained by this device contains a large amount of oil, it must be subjected to a post-processing step to squeeze out the oil before being shipped.

[0005] This is a factor that hinders reduction of processing costs. Food waste comes in a wide variety of forms, from waste discharged from food factories to household waste and waste from restaurants. Selecting a post-processing step depending on the type of material to be dried is cumbersome. The present invention has been made to solve this problem. [Means for solving the problem]

[0006] The following configurations are means for solving the above problems.

[0007] <Configuration 1> This is an apparatus that heats and dries the material to be dried, converting it from a muddy state into a lump state, and then crushing it into granules or fine powder and discharging it. a cylindrical drying chamber; a heating device for heating the inner wall surface and the top surface plate of the bottom plate of the drying chamber; a rotating shaft disposed at the center of the drying chamber; a rotation drive device that rotates the rotation shaft; a plurality of arms extending from the rotation shaft toward the inner wall surface of the drying chamber; a plurality of stirring blades attached to the ends of the plurality of arms, each having an upper surface for placing and lifting up the material to be dried and a scraping edge that fits along the inner wall surface of the drying chamber; a protrusion disposed on an upper surface of the stirring blade for crushing the material to be dried; a plurality of bottom wiping blades extending in the direction of the inner wall surface of the drying chamber on the upper surface of the bottom plate of the drying chamber; The bottom wiping blade scrapes off the material to be dried adhering to the bottom plate of the drying chamber, rolls it up, and sends it toward the stirring blade, and has a side surface that sends oil that has seeped out of the material to be dried and adhered to the bottom surface of the drying chamber into a groove provided on the outer periphery of the bottom surface of the drying chamber, The groove has a bottom surface that is inclined in one direction, This drying device is characterized by having an auxiliary discharge port for discharging the oil sent out by the bottom wiping blade and the oil that seeps out of the material to be dried and flows down the wall surface of the drying chamber, to the outside of the drying chamber, at the destination where the oil flows along the inclination of the groove.

[0008] <Configuration 2> The drying device according to configuration 1, characterized in that an opening and closing device is attached to the auxiliary discharge port, and this opening and closing device changes from a closed state to an open state when the humidity detected by a humidity detector that measures the humidity inside the drying chamber falls below a preset value, thereby discharging the oil from the auxiliary discharge port.

[0009] <Configuration 3> The drying device according to configuration 2, wherein the opening / closing device changes from an open state to a closed state when the humidity detected by the humidity detector falls below a preset value lower than that at the time the opening / closing device is opened.

[0010] <Configuration 4> 3. The drying device according to claim 2, wherein the opening and closing device is configured to transition to a closed state when a preset time has elapsed since the opening.

[0011] <Configuration 5> The drying device according to configuration 1, characterized in that an opening and closing device is attached to the auxiliary discharge outlet, and when a predetermined time has elapsed since the start of the drying process, the opening and closing device is changed from a closed state to an open state, thereby discharging the oil from the auxiliary discharge outlet.

[0012] <Configuration 6> The drying device according to configuration 5, wherein the opening and closing device transitions to a closed state when a preset time has elapsed since the opening. [Effects of the Invention]

[0013] Since oil seeping out from the material to be dried during the drying process is discharged from the auxiliary discharge port, the oil content of the material to be dried after the drying process is reduced, and when the material to be dried is to be used as livestock feed, the process of squeezing out the oil can be eliminated or reduced. To prevent an object to be dried from flowing out from an auxiliary discharge port immediately after the start of drying treatment when the object to be dried put into a drying chamber contains a large amount of moisture. After the oil has been discharged and the drying has progressed, the opening and closing device for the auxiliary discharge outlet can be automatically closed to prevent the granular or powdery material to be dried from being discharged from the auxiliary discharge outlet. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a perspective view showing the overall configuration of the drying device of the first embodiment. [Figure 2]Fig. 2 is an explanatory diagram illustrating the function of the auxiliary discharge port 62 that discharges oil. Fig. 2A is a perspective view of the bottom wiping blade 50 and the bottom plate 54. Fig. 2B is a cross-sectional view taken along line AA. Fig. 2C shows a portion of the cross-section BB, and is a cross-sectional view of the area surrounding the auxiliary discharge port 62. Figs. 2D and 2E are diagrams illustrating the operation of the opening and closing device 60. [Figure 3] Figure 3 is an explanatory diagram of the operation of discharging the material to be dried when the drying process is completed. Fig. 3A is a perspective view showing only a part of the rotating shaft 22 and the bottom wiping blade 50. Fig. 3B is a perspective view showing, with dashed arrows, the force that the material to be dried 51 receives due to the rotation of one bottom wiping blade 50. Fig. 3C is a perspective view of the discharge port 16 provided at the bottom of the drying chamber 18 and the bottom wiping blade 50. DETAILED DESCRIPTION OF THE INVENTION

[0015] The inventors conducted detailed observations and analyses to examine how the state of the material being dried changes during the drying process in a drying device. Their results showed that, when the drying process begins with food residue containing a large amount of moisture, a large amount of steam is released and the moisture escapes. With continued stirring, the material becomes clay-like, and from this point on, oil begins to ooze from the material for a period of time. As the material gradually hardens into a solid mass, the oil oozing stops. The material is dried and finely pulverized, and the granular or fine powder discharged after pulverization absorbs the oil that had oozed earlier. Based on these findings, they developed a device for extracting oil from the drying chamber during the drying process, as described below. The following describes in detail the embodiments of the present invention. [Example]

[0016] (Overall structure of the device) FIG. 1 is a perspective view showing the overall configuration of the drying apparatus of Example 1. The main components of the apparatus are indicated by dashed lines. This apparatus heats and dries the material to be dried, converting it from a muddy state into a lump state, and then pulverizing it into granules or fine powder before discharging it. This apparatus is an improved version of the apparatus described in Patent Document 1. The drying chamber 18 of this apparatus is a vertical cylinder, as outlined by the dashed line. An inlet 14 for introducing the material to be dried is provided in the top lid.

[0017] A discharge port 16 is provided at the bottom of the drying chamber 18 for discharging the material to be dried after drying. The discharge port 16 is opened after drying is completed and the material is discharged. The inner wall surface and bottom plate 54 of the drying chamber 18 are heated by a heating device 20 composed of steam piping or the like. A rotary shaft 22 disposed in the center of the drying chamber 18 is rotated by a rotary drive device 24 such as an electric motor.

[0018] A plurality of arms 26 are fixed to the rotating shaft 22 at appropriate intervals in the vertical direction. The arms 26 extend from the rotating shaft 22 toward the inner wall surface of the drying chamber 18. An agitating blade 32 is attached to the end of each arm 26. An upper surface 28 of the agitating blade 32 functions to lift up the material to be dried. In addition, a scraping edge 30 of the agitating blade 32 functions to scrape off the material to be dried adhering to the inner wall surface of the drying chamber 18.

[0019] A blower blade 40 is attached to the top of the rotating shaft 22 to blow air downward inside the drying chamber 18. This wind circulates dry, hot air inside the drying chamber 18. A protrusion 36 is arranged on the upper surface 28 of the agitating blade 32 to crush the material to be dried that collides with it.

[0020] In addition, a plurality of bottom wiping blades 50 extending from the rotary shaft 22 toward the inner wall surface of the drying chamber 18 are provided on the upper surface of the bottom plate 54 of the drying chamber 18. The bottom wiping blades 50 have the function of scraping off the material to be dried adhering to the upper surface of the bottom plate 54 of the drying chamber 18 with their side surfaces, rolling it up, and sending it toward the agitating blades.

[0021] When the material to be dried has dried into granules or fine powder, the discharge port 16 provided in the side wall at the bottom of the drying chamber 18 opens to discharge the material. Furthermore, the side surface of the bottom wiping blade 50 has the function of sending out oil that has seeped out of the material to be dried and adhered to the upper surface of the bottom plate 54 of the drying chamber 18 in the direction of the groove 58 provided in the outer periphery of the bottom plate 54 of the drying chamber 18.

[0022] Fig. 2 is an explanatory diagram illustrating the function of the auxiliary discharge port 62 that discharges oil. Fig. 2A is a perspective view of the bottom wiping blade 50 and the bottom plate 54. Fig. 2B is a cross-sectional view taken along line AA. Fig. 2C shows a portion of the cross-section BB, and is a cross-sectional view of the area surrounding the auxiliary discharge port 62. Figs. 2D and 2E are diagrams illustrating the operation of the opening and closing device 60.

[0023] The grooves 58 are arranged so as to surround the periphery of the bottom plate 54. As shown in Fig. 2B, when the bottom wiping blade 50 rotates to sweep the upper surface of the bottom plate 54, centrifugal force sends oil adhering to the bottom plate 54 into the grooves 58. As shown in Fig. 2C, the grooves 58 have a bottom surface that is inclined in one direction. The oil sent out by the bottom wiping blade 50 and the oil that seeps out from the material to be dried and runs down the wall surface of the drying chamber 18 collect in the grooves 58.

[0024] The oil flows downward along the slope of the bottom surface of the groove 58. An auxiliary discharge port 62 is located at the bottom of the bottom surface beyond that. The oil in the groove 58 can be discharged from the auxiliary discharge port 62 to the outside of the drying chamber 18. Figs. 2D and 2E will be explained below in conjunction with the operation of the device.

[0025] (Device operation) The operation of the device of the present invention will be described below. The material to be dried by this device is, for example, food residue after removing non-combustible materials and plastic containers. This food residue is dried into granules or fine powder and reused as livestock feed, etc.

[0026] There are many different types of food waste, including household garbage, waste from food factories, and waste from grocery stores and kitchens. All of these contain a large amount of water before being fed into this device, and once fed, they gradually turn into a muddy mess as they are heated and stirred.

[0027] The material to be dried is heated and stirred by the stirring blade 32 of the above-mentioned device. As the material continues to be heated, the moisture gradually evaporates, turning it into clay-like lumps. The arms 26 and the protrusions 36 on the stirring blade 32 break up the lumps of material and throw them upward, further pulverizing the material. When the moisture content reaches about 30%, the material becomes granular with a diameter of about 10 mm. This can sometimes be discharged and used. Alternatively, when the moisture content reaches about 10%, the material becomes a fine powder with a diameter of about 1 mm, and can also be used in this fine powder form. The drying time is controlled according to the application.

[0028] Lumps adhering to the inner wall of the drying chamber 18 are scraped off by the scraping edge 30 of the agitating blade 32, thrown up and pulverized. The bottom wiping blade 50 located at the lower end of the rotating shaft 22 scrapes off the material to be dried adhering to the bottom plate 54 and throws it up. In this way, the material to be dried finally becomes granular or fine powder. Finally, the material to be dried can be discharged from the discharge port 16 by rotating the bottom wiping blade 50.

[0029] During the drying process, when most of the moisture contained in the material is lost and the material becomes clay-like or lumpy, oil begins to seep out of the material. The oil runs down the inner wall of the drying chamber 18 or along the rotating shaft 22 and onto the bottom plate 54. This phenomenon is temporary, and as the agitation and drying / crushing process continues, the oil is reabsorbed into the material. As a result, in the past, the material discharged in the form of granules or fine powder contained a lot of oil, and was shipped as livestock feed after a process to squeeze out the oil.

[0030] In the device of the present invention, this oil is discharged during the drying process, and the oil content in the material to be dried that is discharged in the form of granules or fine powder can be sufficiently reduced. That is, in the device described above, the bottom wiping blade 50 sweeps the oil adhering to the bottom plate 54 toward the outer periphery of the bottom plate 54 by the centrifugal force generated by the rotation of the bottom wiping blade 50.

[0031] This oil flows into the groove 58. Oil that has trickled down the inner wall of the drying chamber 18 also flows into the groove 58. As explained with reference to Figure 2, this groove 58 is arranged so as to surround the outer periphery of the bottom plate 54, and an auxiliary discharge port 62 is provided at one location in this groove 58. The depth of the bottom surface of the groove 58 is inclined so that it becomes deeper as it approaches the auxiliary discharge port 62 as a whole.

[0032] That is, the oil that has flowed into the grooves 58 flows down toward the auxiliary discharge port 62 due to the slope of the bottom surface of the grooves 58. If the auxiliary discharge port 62 is open during the drying process, the oil will be discharged from there. Because the bottom plate 54 is heated, the viscosity of the oil is reduced, and the oil easily flows down the grooves 58 and is discharged from the auxiliary discharge port 62.

[0033] When the drying process has progressed to the point where the material to be dried has turned into granular or fine powder, the powder is discharged from the discharge port 16 provided on the side of the bottom plate 54 as described above. At this time, the oil on the upper surface and surrounding areas of the bottom plate 54 has already been discharged, so the dried material can be prevented from absorbing the oil and being discharged. Therefore, when the dried material is to be used as livestock feed, there is an effect that the work of squeezing out the oil in a later process is not necessary, or the processing time required for squeezing out the oil can be shortened.

[0034] When the drying process starts, the materials to be dried that are put into the drying chamber 18 are often muddy and contain a large amount of water. In this case, if the auxiliary discharge port 62 is open, the materials to be dried may flow out from the outlet. Therefore, the following control is performed.

[0035] When a material to be dried that contains a large amount of moisture is heated and stirred, a large amount of water vapor is initially emitted. As the moisture content decreases through crushing and stirring, the material to be dried turns into a clay-like mass. At this point, there is no longer any need to worry about the material flowing out of the auxiliary discharge port 62. Also, at this time, oil begins to seep out of the clay-like material to be dried all at once. If the auxiliary discharge port 62 is opened at this time, the oil can be efficiently discharged. In other words, the opening and closing device 60 changes from the state shown in Fig. 2E to the state shown in Fig. 2D.

[0036] Therefore, in the case of materials to be dried whose properties are known in advance, it is advisable to control the system so that the auxiliary discharge outlet 62 opens after a predetermined time determined empirically has elapsed since the start of the drying process. Alternatively, a buzzer may sound at the time when the auxiliary discharge outlet 62 should be opened to instruct the worker to open it.

[0037] If the auxiliary discharge port 62 is opened too early, the material to be dried will flow out from the auxiliary discharge port 62. If the auxiliary discharge port 62 is opened too late, oil will accumulate on the upper surface of the bottom plate 54 and some of it will become burnt. Therefore, in the embodiment of the present invention, a mechanism is provided that controls the opening of the auxiliary discharge port 62 at the optimal timing even when processing materials with different properties for each operation.

[0038] The device of this embodiment is equipped with a humidity detector 64 that detects the humidity inside the drying chamber 18. Immediately after the drying process begins, a large amount of water evaporates and the humidity inside the drying chamber 18 reaches 100%. Thereafter, as the material to be dried becomes clay-like, the humidity inside the drying chamber 18 decreases. Here, when the humidity drops below 60%, for example, the opening and closing device 60 is operated to open the auxiliary discharge port 62.

[0039] As a result, the oil that has accumulated in the groove 58 flows out from the auxiliary discharge port 62. After that, the auxiliary discharge port 62 may be left open or may be closed at an appropriate time. However, if the material to be dried becomes granular or finely powdered, the material may flow out from the auxiliary discharge port 62 through the groove 58.

[0040] To prevent this, for example, the opening / closing device 60 may be returned from the open state to the closed state when the humidity detected by the humidity detector 64 falls to or below a preset value that is lower than the humidity detected when the opening / closing device 60 is opened. That is, the opening / closing device 60 transitions from the state shown in Fig. 2D to the state shown in Fig. 2E.

[0041] Alternatively, the opening / closing device 60 may be controlled to transition to a closed state when a preset time has elapsed since the opening. [Example]

[0042] (Discharge of dried material) Figure 3 is an explanatory diagram of the operation of discharging the material to be dried when the drying process is completed. Fig. 3A is a perspective view illustrating only a portion of the rotating shaft 22 and the bottom wiping blade 50, showing the state when the material to be dried 51, which has become granular or finely powdered, is being discharged. Fig. 3B is a perspective view showing, with dashed arrows, the force that the material to be dried 51 receives as a result of the rotation of one bottom wiping blade 50. Because the surface of the bottom wiping blade 50 does not have protrusions 36 like those of the agitating blade 32, the material to be dried 51 is pushed out by centrifugal force so that it slides toward the inner wall of the drying chamber 18.

[0043] Fig. 3C is a perspective view of the discharge outlet 16 and the bottom wiping blade 50 (shown in dashed lines) provided at the bottom of the drying chamber 18. When the drying process is completed, the door 52 of the discharge outlet 16 opens, and the material to be dried pushed out by the bottom wiping blade 50 is discharged from the discharge outlet 16.

[0044] As described above, the bottom wiping blade 50 not only removes oil during the drying process, but also functions effectively to discharge the materials to be dried after the drying process is completed. [Explanation of symbols]

[0045] 14 Inlet 16 Outlet 18 Drying room 20 Heating device 22 Rotation axis 24 Rotation drive mechanism 26 Arms 28 Top 30 scraped edge 32 stirring blade 36 Protrusion 38 Branch end 40 Blower 48 Flat surface 50 Bottom Wiper 51 Materials to be dried 52 Door 54 Bottom plate 56 Arrow 58 Groove 60 Switchgear 62 Auxiliary outlet 64 Humidity detector

Claims

1. This is an apparatus that heats and dries the material to be dried, converting it from a muddy state into a lump state, and then crushing it into granules or fine powder and discharging it. a cylindrical drying chamber; a heating device for heating the inner wall surface and the top surface plate of the bottom plate of the drying chamber; a rotating shaft disposed at the center of the drying chamber; a rotation drive device that rotates the rotation shaft; a plurality of arms extending from the rotation shaft toward the inner wall surface of the drying chamber; a plurality of stirring blades attached to the ends of the plurality of arms, each having an upper surface for placing and lifting up the material to be dried and a scraping edge that fits along the inner wall surface of the drying chamber; a protrusion disposed on an upper surface of the stirring blade for crushing the material to be dried; a plurality of bottom wiping blades extending in the direction of the inner wall surface of the drying chamber on the upper surface of the bottom plate of the drying chamber; The bottom wiping blade scrapes off the material to be dried adhering to the bottom plate of the drying chamber, rolls it up, and sends it toward the stirring blade, and has a side surface that sends oil that has seeped out of the material to be dried and adhered to the bottom surface of the drying chamber into a groove provided on the outer periphery of the bottom surface of the drying chamber, The groove has a bottom surface that is inclined in one direction, This drying device is characterized by having an auxiliary discharge port for discharging the oil sent out by the bottom wiping blade and the oil that seeps out of the material to be dried and flows down the wall surface of the drying chamber, to the outside of the drying chamber, at the destination where the oil flows along the inclination of the groove.

2. 2. The drying device according to claim 1, wherein an opening and closing device is attached to the auxiliary discharge port, and when the humidity detected by a humidity detector that measures the humidity inside the drying chamber falls below a preset value, the opening and closing device changes from a closed state to an open state, thereby discharging the oil from the auxiliary discharge port.

3. 3. The drying device according to claim 2, wherein the opening / closing device changes from an open state to a closed state when the humidity detected by the humidity detector falls below a preset value that is lower than the humidity detected when the opening / closing device is open.

4. 3. The drying device according to claim 2, wherein the opening and closing device is changed to a closed state when a preset time has elapsed since the opening.

5. The drying device according to claim 1, characterized in that an opening and closing device is attached to the auxiliary discharge outlet, and when a predetermined time has elapsed since the start of the drying process, the opening and closing device is changed from a closed state to an open state to discharge the oil from the auxiliary discharge outlet.

6. 6. The drying device according to claim 5, wherein the opening and closing device is brought into a closed state when a preset time has elapsed since the opening.

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