JP2003175380A - Compression molding method for plant waste - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a good rod-shaped compression molded article from plant waste regardless of the kind thereof. <P>SOLUTION: The plant waste supplied to a compression molding machine 1 is steamed by a steamer 11 to positively accelerate the hydrolysis of cellulose or hemicellulose being a main component of the plant waste by steam. A viscous substance is formed by this hydrolysis and used as a binder to obtain the compression molded article not getting out of shape. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for compression-molding a plant waste such as grass clippings generated in weeding work on a river bank.

[0002]

2. Description of the Related Art As a compression molding machine for producing a rod-shaped compression molded article from combustible waste contained in municipal waste, for example, a screw type machine as described in JP-A-11-342497 is known. Has been. In this screw type compression molding machine, a pair of screws whose rotating shafts are parallel to each other are arranged in a cylindrical casing, and a combustible waste supplied from a supply port provided at one end of the casing is screwed. In this case, the rod-shaped compression molded article is discharged while being compressed while being conveyed to the other end side and discharged from a discharge nozzle provided on the other end side of the casing.

In the case of treating this flammable waste, the thermoplastic resin contained in the waste is softened by the frictional heat generated by the transportation and kneading in the casing, and the softened thermoplastic resin is compressed and molded. It cures and retains the shape of the compression molding. Further, it is considered that the kitchen waste contained in the waste also plays a role of an adhesive such as starch paste and helps to maintain the shape of the compression molded product.

In recent years, such screw type compression molding machines have been used to compression-mold plant wastes such as mowed grass produced in weeding work on river banks, etc. This technology is being put to practical use. This rod-shaped compression molded product is used as waste for solid fuel and the like.

Unlike the above-mentioned flammable wastes, plant wastes such as grass clippings do not contain thermoplastic resin or kitchen waste,
When the plant waste is cuttings that contain many Asteraceae plants such as Solidago or Artemisia, a relatively good compression molded product can be obtained by adjusting the water content of these cuttings to an appropriate range by sun drying etc. be able to.

It is presumed that the reason why the grass of the Asteraceae plant can retain the rod-shaped shape even after being discharged from the discharge nozzle of the screw type compression molding machine is as follows. As described above, in the casing of the compression molding machine, the object to be treated is kneaded and the temperature rises due to frictional heat generation. Due to this temperature rise, the water contained in the grass to be treated or the like becomes steam, and the steam hydrolyzes while kneading the main components of the grass or the like, such as cellulose and hemicellulose. Cellulose and hemicellulose are high molecular compounds of polysaccharides, which are hydrolyzed to lower the molecular weight. Although not specified, a sticky substance is present in this low molecular weight substance, and acts as an adhesive such as starch paste.

[0007] However, when the plant waste is cuttings containing a large amount of grasses such as Pondella spp., A good compression molded product cannot be obtained. This is considered to be because the grasses have thin stems, thin leaves, and are harder than the Asteraceae plants, so that they are difficult to be kneaded in the casing and the above hydrolysis is not promoted so much.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to obtain a good rod-shaped compression molded article regardless of the type of plant waste.

[0009]

In order to solve the above-mentioned problems, a method for compression-molding plant waste according to the present invention comprises a steaming step of steaming plant waste and a compression molding of steamed plant waste. The method of performing the molding process was adopted.

That is, by steaming the plant waste before compression molding, the steam actively promotes the hydrolysis of cellulose, hemicellulose, lignin, etc., which are the main components of the plant waste, and the Gramineae which are not easily hydrolyzed. Even if the waste contains a large amount of plants and the like, the viscous substance is sufficiently generated by hydrolysis so that the compression molded product can be maintained in a good shape. By performing this steaming process,
Hydrolysis is promoted even in the treatment of a plant waste containing a lot of Asteraceae plants, and the compression molded product can be more resistant to shape collapse.

As the compression molding machine used in the compression molding step, in addition to the screw type extruding from the nozzle with the above-mentioned screw, a roll type using a pair of compression rolls or a briquetting roll, a ring shape, a disk shape, a cylindrical shape. Various types such as a relative rotary die type in which a relative rotary body with a die is combined with a porous die such as a cylinder type, a cylinder type pushed out from a nozzle by a cylinder, a press type compressed by a ram, etc. can be adopted. Since cellulose and hemicellulose are softened by being steamed, the fluidity at the time of compression molding is improved and the load on these compression molding machines can be reduced.

The hydrolysis can be further promoted by kneading the plant waste steamed in the steaming step.

In the compression molding step, in a casing having a supply port at one end and a discharge nozzle at the other end,
A screw type compression molding machine in which a pair of screws whose rotating shafts are parallel to each other is arranged from the one end side to the other end side, and the plant waste supplied from the supply port is discharged from the discharge nozzle is used. It is suitable.

The steaming step is carried out by the screw type compression molding machine used in the compression molding step, and the steamed plant waste is put into the screw type compression molding machine again to be compression-molded. A separate device is not required, and the plant waste in the steaming step can be kneaded. As described above, since the screw type compression molding machine raises the temperature in the casing due to frictional heat generation, the water contained in the plant waste or the water separately supplied can be evaporated and used as a steamer. .

By providing a spray for spraying water in the steaming step, fine water can be attached to the plant waste to humidify it, and the plant waste can be steamed more uniformly.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIGS. 1 to 3 show a first embodiment. FIG. 1 shows the configuration of an apparatus for compression molding plant waste. This apparatus is composed of a compression molding machine 1 for molding plant waste into a rod-shaped compression molding, and a steamer 11 for steaming the plant waste supplied to the compression molding machine 1.

The steamer 11 has a horizontal casing 12
Of the hopper 13 at the upper part of one end of the
Is provided with a spray 15 for spraying water that humidifies the plant waste in the hopper 13, and a jacket 16 for a heat medium that covers and heats the casing 12. Further, inside the casing 12, there is provided a screw 17 for kneading the plant waste fed from the hopper 13 and transporting it to the discharge port 14.

By supplying the heating medium to the jacket 16, the inside of the casing 12 is heated to 90 ° C. to 110 ° C., and the humidification water from the spray 15 and the water contained in the plant waste become steam, and the casing is produced. The plant waste in 12 is steamed while being kneaded by the screw 17. At this time, cellulose, hemicellulose, etc., which are the main components of the plant waste, are hydrolyzed to produce an adhesive substance.

The compression molding machine 1 is of a screw type. A horizontal casing 2 is provided with a pair of screws 3 having rotating shafts 3a parallel to each other. A supply port 4 connected to the discharge port 14 is provided, and a plurality of discharge nozzles 6 are provided on a discharge plate 5 forming the other end side end surface of the casing 2.

As shown in FIGS. 2 and 3, the casing 2 of the compression molding machine 1 is divided into upper and lower halves, and a split type liner 7 having abrasion resistance is lined inside. The inner surface of the split liner 7 is formed into a tubular shape in which two cylinders are wrapped, and a pair of parallel screws 3
Are arranged along each cylinder.

From the discharge port 14 of the steamer 11 to the supply port 4
The steamed plant waste that is supplied to is gradually compressed while being conveyed to the discharge plate 5 side with the rotation of the pair of screws 3, and the compression pressure becomes maximum on the front side of the discharge plate 5, and each discharge nozzle is discharged. 6 is formed into a rod shape and discharged. The rod-shaped compression-molded product discharged from each discharge nozzle 6 is cut into a regular size by a cutter 8 provided in the vicinity of the outlet of the discharge nozzle 6.

In the above-described embodiment, the screw type compressor is used as the compression molding machine. However, in addition to this, various types such as the roll type, the relative rotary die type, the cylinder type and the press type as described above are used. The compression molding machine of can be adopted.

FIG. 4 shows a second embodiment. This apparatus uses the screw type compression molding machine 1 also as a steamer, and a hopper 10 provided with a spray 9 for spraying water for humidifying plant wastes at a supply port 4 of the compression molding machine 1.
Is provided, and a constant quantity feeder 21 for supplying steamed plant waste to the supply port 4 is provided.

This compression molding machine 1 also has a pair of parallel screws 3 in the casing 2 as in the first embodiment.
, A plurality of discharge nozzles 6 are provided on the discharge plate 5, and a cutter 8 is provided at the outlet thereof. In addition, in this embodiment, when the compression molding machine 1 is used as a steamer, a recovery box 22 for recovering the steamed plant waste discharged from the discharge nozzle 6 is provided.

The fixed quantity feeder 21 includes a recovery box 22.
The screw 24 is arranged at the bottom of the casing 23 having an open upper end into which the steamed plant waste collected in FIG.
A fixed amount is supplied to the discharge port 25 connected to the supply port 4.

In this embodiment, first, the plant waste is put into the compression molding machine 1 as a steamer from the hopper 10,
It is conveyed to the discharge plate 5 side while being kneaded by the screw 3.
At this time, due to the temperature rise in the casing due to frictional heat generation, the humidifying water from the spray 9 and the water contained in the plant waste become steam, the plant waste in the casing 12 is steamed, and the main component, cellulose. And hemicellulose are hydrolyzed to produce a sticky substance. The steamed plant waste is discharged from each discharge nozzle 6 while being compressed, and is collected in the collection box 22.

Next, the discharged matter collected in the collecting box 22 is put into the constant quantity feeder 21. When the plant waste contains a large amount of asteraceae plants, the discharge collected in the collection box 22 may include a stick-shaped compression molded product. The product molded as a rod-shaped compression molded product in this manner may be separated as a product from the recovery box 22 or may be put into the fixed quantity feeder 21 together with the unformed discharged product.

The steamed plant waste introduced into the constant quantity feeder 21 is conveyed to the discharge port 25 by the screw 24 and is quantitatively supplied to the supply port 4 of the compression molding machine 1. This supply port 4
Similarly to the first embodiment, the steamed plant waste supplied to is gradually compressed while being conveyed to the discharge plate 5 side by the screw 3, and discharged from each discharge nozzle 6 as a rod-shaped compression molded product. The cutter 8 cuts to a fixed length.

In each of the above-mentioned embodiments, the spray for humidifying the plant waste to be supplied is provided. However, since the plant waste usually contains water, the humidifying means such as spray can be omitted. In the steaming process, it is desirable to provide a temperature raising means and a thermometer to control the temperature at about 90 ° C to 110 ° C, but the temperature rise due to frictional heat etc. forces the water and humidification water contained in the plant waste. If you make the conditions to evaporate into
These can be omitted.

Further, in each of the above-mentioned embodiments, a steamer dedicated to the steaming step is used or a compression molding machine is used. However, the compression molding method for plant waste according to the present invention is performed before compression molding. It suffices to steam the plant waste, and various steaming methods such as directly spraying steam onto the plant waste can be adopted.

Further, the steaming step can be used in combination with other steps before the compression molding step. For example, when crushing the plant waste in the previous step, the crusher may be provided with a temperature raising means in the casing and a humidifying means if necessary, and the crushing step may steam the crushed plant waste. . If the heat generated during the crushing is used, it is possible to reduce the heat energy for raising the temperature in the casing.

[0032]

EXAMPLE Method of the first embodiment described above (Example 1)
Then, with respect to the method of the second embodiment (Example 2), a compression molding test of grass as plant waste was conducted. The cut grass samples to be supplied include those containing a large amount of Poaceae of the family Gramineae, and those containing a large amount of Asteraceae of the family Asteraceae and Mugwort.
Each was dried in the sun for 3 days to have a water content of about 15%, which was cut into about 20 mm. As a comparative example, a compression molding test was also carried out in which the respective grass samples were directly supplied to the compression molding machine 1 in a fixed amount without performing the steaming step.

[0033]

[Table 1]

Table 1 shows the results of each test. According to the methods of Examples 1 and 2, a strong and very good rod-shaped compression molded product could be obtained for any of the cut grass samples. On the other hand, according to the method of the comparative example, a substantially good rod-shaped compression molded product could be obtained for the grass sample mainly composed of Asteraceae, but in the case of the grass sample mainly composed of Gramineae, the discharge nozzle 6 was used.
The discharge from the product did not become a compression-molded product, or it became a compression-molded product and immediately disintegrated.

[0035]

As described above, according to the method for compression-molding plant waste of the present invention, the plant waste before compression-molding is steamed. Therefore, cellulose or hemicellulose, which is the main component of the plant waste, is steamed with the steam. By virtue of the acceleration of hydrolysis such as to produce a sticky substance, a good compression molded product which does not lose its shape can be obtained by using this sticky substance as a binder.

[Brief description of drawings]

FIG. 1 is a schematic front view showing an apparatus used in a compression molding method for plant waste according to a first embodiment.

FIG. 2 is a cutaway plan view showing the compression molding machine of FIG.

FIG. 3 is a side sectional view of FIG.

FIG. 4 is a schematic front view showing an apparatus used in the compression molding method for plant waste according to the second embodiment.

[Explanation of symbols]

1 compression molding machine 2 casing 3 screws 3a rotating shaft 3b screw blade 4 supply ports 5 discharge plate 6 discharge nozzle 7 liner 8 cutters 9 spray 10 hoppers 11 steamer 12 casing 13 hoppers 14 outlet 15 spray 16 jacket 17 screws 21 Fixed amount feeder 22 Collection Box 23 casing 24 screws 25 outlet

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Giantakabayashi             2-14-17 Shinonome, Higashi-ku, Hiroshima-shi (72) Inventor Nobumasa Tsumura             2322 Oofukucho, Mine-shi (72) Inventor Kenichiro Yanase             7-7-10-10 Yagi, Asaminami-ku, Hiroshima-shi (72) Inventor Hiromichi Matsuoka             3-14 Hatchobori, Naka-ku, Hiroshima-shi (72) Inventor Jun Fujii             1-12-19 Kitahori, Nishi-ku, Osaka City Stock Association             Kurimoto Ironworks (72) Inventor Masaru Hashimoto             1-12-19 Kitahori, Nishi-ku, Osaka City Stock Association             Kurimoto Ironworks F-term (reference) 4D004 AA01 BA03 CA03 CA04 CA15                       CA22 CA34 CA50 CB12 CB16                       CB28 CB31 CB42 CB50 CC03                 4G078 AA30 AB20 BA01 BA09 CA01                       CA05 CA12 CA17 DA09 EA01                       EA08 EA10                 4H015 AA12 AB01 BA13 BB03 BB05

Claims (5)

[Claims] 1. A method for compression-molding plant waste, comprising a steaming step of steaming plant waste and a compression-molding step of compression-molding the steamed plant waste. 2. The method for compression-molding plant waste according to claim 1, wherein the plant waste steamed in the steaming step is kneaded. 3. In the compression molding step, in a casing having a supply port at one end and a discharge nozzle at the other end,
A screw type compression molding machine in which a pair of screws whose rotating shafts are parallel to each other is arranged from the one end side to the other end side, and the plant waste supplied from the supply port is discharged from the discharge nozzle. Item 3. A method for compression-molding a plant waste according to Item 1 or 2. 4. The screw type compression molding machine used in the compression molding step, wherein the steaming step is performed, and the steamed plant waste is again charged into the screw type compression molding machine for compression molding. 3. The method for compression-molding plant waste according to item 3. 5. The plant waste compression molding method according to claim 1, wherein a spray for spraying water is provided in the steaming step.