WO2005021432A1

WO2005021432A1 - Silicic acid-containing powder production method and silicic acid-containing powder production system

Info

Publication number: WO2005021432A1
Application number: PCT/JP2004/012103
Authority: WO
Inventors: Joji Takase
Original assignee: Nishimuragumi Co., Ltd.
Priority date: 2003-08-27
Filing date: 2004-08-24
Publication date: 2005-03-10
Also published as: TW200507961A; JP2006187674A; JP3579417B1; KR20060056992A; BRPI0413865A

Abstract

It is intended to provide a method of producing a silicic acid-containing powder and a system for producing a silicic acid-containing powder whereby rice hulls and straws are treated within a short time at a low cost without decreasing silicic acid and thus a powder containing natural silicic acid conveniently usable as a straight fertilizer can be produced. The above object is achieved by a method of producing a silicic acid-containing powder from rice hulls or straws which comprises jetting high-pressure steam into rice hulls or straws fed into a treatment container (2) and then powdering the contents while maintaining the pressure in the treatment container (2) at 1.45 MPa to 1.96 MPa.

Description

Specification

Method for producing powder containing caic acid and system for producing powder containing caic acid

Technical field

[0001] The present invention is suitable for producing a powder containing a natural caic acid by changing the properties of the rice husk etc., which reuses the natural caic acid contained in rice hulls, rice straw, wheat straw and the like. TECHNICAL FIELD The present invention relates to a method for producing a powder containing caic acid and a system for producing a powder containing caic acid.

Background art

[0002] Hitherto, it has been known that caic acid is effective in strengthening rice and preventing diseases. However, in recent years, the content of caiic acid in paddy fields has been decreasing, and it has become necessary to apply and replenish the caiic acid separately. At present, the mainstream of caicic acid applied to paddy fields is one that is artificially extracted from mineral materials or that uses burnt rice husk charcoal. However, in practice, it is not easy to extract the citric acid. For example, when extracting caic acid from mineral materials, there is a problem in that the ore cutting, crushing, and other processes are complicated, and require time, time, and cost. In addition, in the case of rice husk charcoal, there is a problem that the amount of carbonic acid disappears depending on the degree of carbonization and the content thereof is considerably reduced. Of course, the burden of processing costs is large.

[0003] On the other hand, rice husks and rice straw are industrial wastes and must be properly treated. However, due to the burden of processing costs, spontaneous ignition often occurs when they are left unloaded. The concern is that the problem is raised.

[0004] Conventionally, as a technique for effectively reusing the cayic acid contained in rice hulls, Japanese Patent Application Laid-Open No. 8-224488 proposes an invention of grinding rice hulls (Patent Document 1). The present invention is characterized in that rice hulls in a dry state are finely pulverized by an impact pulverizer, and the finely pulverized product is mixed with a natural aluminosilicate or a chemically treated product thereof to form a rice husk-containing composition. To manufacture. Then, by spraying the rice husk-containing composition on the paddy field, the siliric power is reduced to the paddy field!

Patent Document 1: Japanese Patent Application Laid-Open No. 8-224488

Disclosure of the invention Problems the invention is trying to solve

[0006] However, while the invention described in Japanese Patent Application Laid-Open No. 8-224488 focuses on fine powder milling, it is necessary to efficiently extract only caic acid. I can't do it. In other words, since the other components contained in the rice hulls are also included as they are, the purity of the keic acid is low. In addition, harmful polymer compounds may be contained without being treated. Furthermore, the impact crusher has a problem that maintenance of the impact crusher is difficult and cost burden is large, and the crushed rice husk is small but has high hardness, so that the impact crushed parts are damaged quickly. On the other hand, according to the conventional invention, a chemical substance such as a natural aluminosilicate is mixed and granulated, but there is also a need not to give a paddy field containing a chemical substance as much as possible. In the end, with conventional technology, it was not possible to extract caffeic acid from rice hulls effectively, and in most cases, rice husks were incinerated.

[0007] The present invention has been made to solve such a problem, and the rice husk and straw are processed in a short time and at low cost without losing the keic acid, and are used as single fertilizers. It is an object of the present invention to provide a method for producing a powder containing caic acid and a system for producing a powder containing caic acid, which is capable of producing a powder containing caustic acid.

Means for solving the problem

[0008] A feature of the method for producing a caicic acid-containing powder according to the present invention is that rice hulls or straws are charged into a processing vessel, steam is injected into the processing vessel to increase the internal pressure and temperature, and the rice husks or straws are reduced. The point is that the treatment is carried out under the steam pressure at which the powder is formed without burning. According to such a method, the rice husks and straw are compressed by the action of pressure on the rice husks and straw, and the heating and hydrolysis of steam accompanying the steam pressure, and then the pressure in the container is gradually reduced. When the pressure is reduced, binding molecules are separated and decomposed, resulting in a change in properties such as the initial carbonization and refining of rice husk and straw.

[0009] Further, in the present invention, it is preferable that the pressure in the processing container is kept at 1.45 MPa to 1.96 MPa to perform the powdering treatment.

[0010] Further, in the present invention, in order to more effectively produce the caiic acid-containing powder, the pressure in the processing container is kept at 1.65 MPa to 1.85 MPa for 5 minutes to 30 minutes to perform powdering treatment. Is preferred. [0011] Further, a feature of the system for manufacturing a powder containing caieic acid according to the present invention is that a processing vessel provided with a stirring means, and steam pressurized into rice husk or straw injected into the processing vessel is injected. And a control means for controlling the amount of steam injected by the steam injection means so as to maintain a pressure at which the rice hulls or straw in the processing vessel can be pulverized without burning. is there. According to such a configuration, in the processing vessel, the rice husks and straw are compressed from all directions by the action of the pressure on the rice husks and straw, and the heating and hydrolysis of water vapor accompanying the steam pressure. Thereafter, when the pressure in the processing vessel is gradually reduced, separation and decomposition of the bound molecules are started, and as a result, a property change such as initial carbonization and miniaturization of the rice husk and straw occurs.

[0012] Further, in the present invention, it is preferable that the control means controls the injection amount of steam by the steam injection means so that the pressure in the processing container is maintained at 1.45 MPa to 1.96 MPa. It is more desirable to control the pressure in the processing container to be maintained at 1.65 MPa to 1.85 MPa for 5 minutes to 30 minutes.

The invention's effect

[0013] According to the present invention, a natural caustic acid which is easy to use as a single fertilizer is obtained by powdering rice husks in a short time and at low cost without extinguishing the caiic acid component contained in the rice husk and straw. Can be produced.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, a preferred embodiment of a system for producing a powder of Ca-containing acid according to the present invention will be described with reference to the drawings.

FIG. 1 is a schematic view showing a cayic acid-containing powder production system 1 of the present embodiment. The production system 1 for a caic acid-containing powder according to the present embodiment includes a processing container 2 for storing and processing rice hulls and straw, and a stirring means 3 for stirring the rice hulls and straw put into the processing container 2, Steam injection means 4 for injecting high-pressure steam into rice husks and straws in processing vessel 2, pressure adjusting means 5 for adjusting pressure in processing vessel 2, stirring means 3, steam injection Control means 6 for controlling the means 4 and the pressure adjusting means 5.

[0016] To describe each component of the present embodiment in more detail, the processing container 2 is configured by a first-class pressure container having pressure resistance, and is configured to process rice husks and straw therein. It has become. In addition, an input port 21 for rice husks and straw is provided at an upper portion of the processing container 2, and an outlet 22 is provided at a lower portion. The inlet 21 and the outlet 22 have a closed structure capable of maintaining the pressure in the processing container 2 when processing rice husks and straw. In addition, a sealing mechanism (not shown) for maintaining the hermeticity between the horizontal rotation shaft 31 of the stirring means 3 and the processing container 2 described later is provided. The input port 21 and the discharge port 22 are provided with a system control in which the opening / closing operation does not react unless the pressure in the processing container 2 reaches 0.015 MPa or less in consideration of safety. Further, the processing container 2 is provided with an upper temperature sensor 23a, a lower temperature sensor 23b, and a pressure sensor 24, and detects the temperature and the pressure in the processing container 2.

[0017] Next, the stirring means 3 is for pressurizing and heating the whole rice husk and straw throughout. The stirring means 3 is axially supported by a horizontal rotation shaft 31 in the longitudinal direction in the processing vessel 2. A stirring blade 32 inclined forward with respect to a vertical plane is attached to the horizontal rotation shaft 31. It is configured. The horizontal rotation shaft 31 is connected to a drive motor 33 capable of rotating the same forward and backward. The stirring means 3 is configured to gradually transfer the input rice husks and straws while stirring, and extends from the input port 21 to the discharge port 22. On the other hand, the drive motor 33 is a motor whose rotation speed and direction can be controlled by inverter control, and reciprocates in the processing vessel 2 as necessary until the chaff or straw is pulverized into desired properties.

Next, the steam injection means 4 has a boiler 41 for generating high-pressure steam, and an air supply pipe 42 for supplying the steam generated from the boiler 41 into the processing vessel 2. The pressure of the steam generated in the boiler is maintained at a constant value, and the pressure in the processing vessel 2 is adjusted by the injection amount of the high-pressure steam. In the present embodiment, saturated steam is injected as high-pressure steam! Since the temperature is determined in association with the pressure of the saturated steam, the inside of the processing vessel 2 is maintained at a high temperature. Further, the air supply pipe 42 is located at a position higher than the horizontal rotation shaft 31 with respect to the processing container 2 and is connected in a substantially horizontal direction. This is optimal when the rice husks and straw in the processing vessel 2 are not under pressure due to accumulation, that is, immediately before being stirred and floating in the air, and covered with the rice husks and straw. This is because high processing efficiency can be obtained. Next, the pressure adjusting means 5 is connected to a pressure adjusting valve 51 which can be freely opened and closed by electric control, and an exhaust pipe 52 for exhausting the water vapor in the processing chamber 2 via the pressure adjusting valve 51. It is configured. Then, when the pressure in the processing container 2 exceeds a predetermined value, the pressure adjusting valve 51 is opened, the pressure in the processing container 2 is released, and the predetermined pressure is maintained. Further, a cooling device 8 is connected to the exhaust pipe 52 via a silencer 7, so that the steam from the processing container 2 is cooled and liquefied and supplied to a wastewater treatment facility 9. . In addition, the silencer 7 is designed so that it can be installed in urban areas, etc., in compliance with the noise control regulations.

[0020] Next, the control means 6 is electrically connected to the stirring means 3, the steam injection means 4, and the pressure adjusting means 5, and controls these. The control means 6 controls the rotation direction and the rotation speed of the drive motor 33 to control the stirring and transfer time of the rice husk and the straw in the processing container 2. Further, the control means 6 controls the amount of steam injected by the steam injection means 4 so that the pressure for powdering the rice hulls or straw in the processing vessel 2 without burning is maintained for a certain time. In the present embodiment, the pressure in the processing container 2 is maintained at 1.45 MPa to 1.96 MPa based on the experimental results of the examples described later. If the temperature and pressure in the processing vessel 2 decrease, the temperature and pressure are increased by increasing the injection amount of high-pressure steam from the steam injection means 4. Conversely, when the temperature or pressure in the processing container 2 rises, the pressure regulating valve 51 of the pressure regulating means 5 is opened to discharge high-pressure steam to lower the temperature and pressure. The control means 6 is electrically connected to each of the temperature sensors 23a and 23b and the pressure sensor 24 in the processing vessel 2, and based on these detection results, the temperature in the processing vessel 2 is controlled. And feedback control to maintain the pressure at a predetermined value.

Next, a method for producing a cayic acid-containing powder by the caffeic acid-containing powder producing system 1 of the present embodiment will be described.

First, rice husks and straw are charged into the processing container 2 from the input port 21. At this time, the pressure in the processing vessel 2 is set in advance to the control means 6 so as to be 1.45 MPa to 1.96 MPa, and the time for maintaining the set pressure, the stirring time, and the pressure in the vessel corresponding to the set pressure are set. Set the temperature individually. In this case, the pressure holding time is set so that the rice hulls and straw The stirring time, which is preferably set to the start time, is preferably set to a time sufficient for the chaff or straw to be powdered. The temperature inside the container is the temperature associated with the saturated steam pressure.

The rice husks and straws charged into the processing container 2 are gradually transferred to the outlet 22 side while being largely stirred by the stirring blades 32. Depending on the processing amount, the force may not be completed by only one-way transfer. In this case, the drive motor 33 is reversed and transferred to the input port 21 side for reciprocal transfer. Even with the smaller processing vessel 2, a sufficient stirring time can be obtained.

During this stirring, high-pressure steam is injected into the processing container 2 from an air supply pipe 42 mounted above the horizontal rotation shaft 31. Therefore, when the rice husks and straw are scattered above the horizontal rotating shaft 31 by the stirring of the stirring means 3, high-pressure steam can be effectively blown. Therefore, the heating accompanying the steam pressure and the hydrolysis of steam are effectively advanced, and the rice husks and straw are compressed.

[0025] Further, while the rice husks and straw are being stirred, the control means 6 keeps the temperature in the processing vessel 2 at the set temperature based on the detection results of the temperature sensors 23a, 23b and the pressure sensor 24. At the same time, the steam injection means 4 and the pressure adjustment means 5 are controlled so that the pressure is maintained at 1.45 MPa-1.96 MPa.

When the set pressure holding time has elapsed, the control means 6 controls the steam injection means 4 to stop the injection of steam, and controls the pressure adjustment means 5 to open the pressure adjustment valve 51. Then, the high-pressure steam in the processing container 2 is exhausted to the exhaust pipe 52, and the pressure in the processing container 2 is reduced. As a result, rice husks and straws undergo separation and decomposition of binding molecules, resulting in a change in properties such as initial carbonization and miniaturization. In addition, in this initial carbonization state, the keic acid contained in rice husks and straw remains almost without disappearing. The powdered rice hulls and straw are transferred to the outlet 22 and taken out, and the discharged water is supplied to the wastewater treatment equipment 9 for purification treatment.

Next, a specific example of the present embodiment will be described. In each of the following examples, an experiment was conducted to find conditions for obtaining easy-to-use monoacid fertilizer from rice hulls in a short time. In this experiment, the rice husk was changed by changing the pressure in the processing vessel 2 and the pressure holding time. Was observed. Fig. 2 shows these experimental conditions and the processing results. Digital photographic images of rice hull before and after processing are shown in Figure 3 to Figure 8, respectively.

[0028] In the experiment of this example, a processing vessel 2 having a capacity of 3000 liters was used, the temperature in the vessel was maintained at about 200 ° C, which is a temperature associated with the saturated steam pressure, and the filling rate of rice hulls was 65%. % —Filled to 95%. In addition, the stirring speed is 2-18 rpm until the value of the lower temperature sensor 23b matches the value of the upper temperature sensor 23a in order to stir the rice husks more evenly. Until that time, it was 5-15 rpm.

Example 1

[0029] In Example 1, the processing was performed while maintaining the processing pressure in the processing container 2 at less than 1. OMPa. FIG. 4 shows the rice husks processed according to the first embodiment. As a result, no change was observed in the shape even after the treatment for 10 minutes to 90 minutes, and the color slightly changed to a dark brown color.

Example 2

Next, in Example 2, the processing was performed while maintaining the processing pressure in the processing container 2 at 1.45 MPa. Figure 5 shows the processed rice hulls. As a result, the treatment was completed until the pressure was reduced to about half in 10-90 minutes. Observation of the morphology of the treated rice hulls revealed that the rice husks had turned black, but did not reach powdering, and each rice hull was in a withered state. The moisture content of the treated rice husks is 5.8%, which is a good value, and the residual silicon content is 14.25%, which is a sufficient content and can be used as a single fertilizer.

Example 3

In Example 3, the processing was performed while maintaining the processing pressure in the processing container 2 at 1.65 MPa.

Figure 6 shows the rice hulls after the treatment. As a result, it was possible to perform powdering in a short pressure holding time of 10 to 30 minutes. After the treatment, the moisture content of the rice husks was 43.5%, and residual silicon was detected at 11.96%. Powdering increases the solubility and improves usability as a fertilizer.

Example 4 In Example 4, the processing was performed while maintaining the processing pressure in the processing container 2 at 1.85 MPa. Figure 7 shows the rice hulls after the treatment. As a result, it was possible to process very fine powder in a very short time of 5 to 10 minutes. The moisture content of the rice husks after the treatment was reduced to 25.5%, and 9.56% of the residual silicon was detected, indicating that it had good properties as single fertilizer.

Example 5

In Example 5, the processing was performed while injecting steam to maintain the pressure in the processing container 2 at 1.96 MPa. Figure 7 shows the rice hulls after the treatment. As a result, the powder could be processed into a fine powder in a pressure holding time of 5 to 15 minutes. The moisture content of the treated rice husks was 25.0%, and the residual silicon was detected at 9.0%, indicating that the rice husks could be used as single fertilizer. However, there is a decrease in the residual silicon due to the initial carbonization. In addition, the pressure holding time can be short, but the time required to increase the pressure to this pressure is strong, and the practicality is somewhat lacking.

[0034] Examining the experimental results of the above examples, it can be realized that the processing of rice hulls can be realized in a short time without losing the keic acid, and is easy to use as a single fertilizer! As for the processing conditions, the pressure in the processing vessel 2 is preferably maintained at 1.45 MPa or more and 1.96 MPa or less, and more preferably the pressure is maintained at 1.65 MPa or more and 1.85 MPa or less for 5 minutes to 30 minutes. That is. The reason for holding at a high temperature and a high pressure for a certain time is to add a margin condition for decomposing the chaff. The decomposition of rice husk is started as slowly as possible, and the decomposition proceeds along the curve simultaneously with the start of decompression. At this time, the moisture and water vapor contained in the rice hulls are cooled, and the condensed moisture is released outside the container as the pressure changes from pressureless to pressureless, and the properties are converted to a substance with an appropriate moisture content. You.

[0035] Normally, when plants are decomposed by microorganisms in nature, it takes 36 months or more for 6 months to reach the compost state. According to the system of the present embodiment, the compost can be composted in an extremely short time of about 60 to 90 minutes including the time of pressure increase, and the fertilizer can be safely treated under sterile conditions.

[0036] The configurations of the present embodiment are not limited to those described above, and can be appropriately changed.

[0037] For example, in the above-described embodiment, the air supply pipe 42 and the exhaust pipe 52 are configured separately and independently. However, some may use a common noise. This causes a problem that, when the processed rice husk changes to a powdery state, when the pressure in the processing vessel 2 is reduced, the powder is transmitted along with the water vapor through the exhaust pipe 52 to clog the valve. For this reason, by using a common steam injection path and exhaust path, a cleaning process for removing the processing powder clogged in the valve during the steam injection is also performed. That is, as shown in FIG. 9, two paths are provided for injecting steam from the boiler 41 into the processing container 2, and the two exhaust paths are also reversely fed. A path is provided on the way to branch to the exhaust pipe 52. An air supply valve 43 and an exhaust valve 53 are attached to the air supply pipe 42 and the exhaust pipe 52, respectively. Further, a check valve 10 is provided in front of the boiler 41. Further, a control valve 11 for adjusting the flow rate of steam is provided in the common path. A switching valve 12 is provided on a path extending from the exhaust pipe 52 to the air supply pipe 42, and the switching valve 12 switches between steam injection and reduced pressure exhaust. That is, at the time of steam injection, the switching valve 12 is opened and the exhaust valve 53 of the exhaust pipe 52 is closed, so that two paths from the boiler 41 to the processing container 2 are opened. On the other hand, at the time of depressurizing exhaust, the exhaust valve 53 is opened, and the air supply valve 43 and the switching valve 12 are closed. And exhausted to the exhaust pipe 52. At this time, the processing powder may be clogged in the valve in the middle. Since steam flows again in the direction of the processing vessel 2 at the next steam injection, cleaning is performed so as to remove the powder clogged in each valve at the same time. Brief Description of Drawings

FIG. 1 is a schematic diagram showing an embodiment of a system for producing a powder containing caic acid according to the present invention.

FIG. 2 is a table showing processing conditions and processing results of Examples 1 to 5 in the present embodiment.

FIG. 3 is a digital photographic image showing chaff before processing in each example.

FIG. 4 is a digital photographic image showing chaff after processing under the processing conditions of Example 1.

FIG. 5 is a digital photographic image showing chaff after processing under the processing conditions of Example 2.

FIG. 6 is a digital photographic image showing chaff after processing under the processing conditions of Example 3.

FIG. 7 is a digital photographic image showing chaff after processing under the processing conditions of Example 4. FIG. 8 is a digital photographic image showing chaff after processing under the processing conditions of Example 5.

FIG. 9 is a schematic diagram showing a valve opening / closing system during pressurization and depressurization of the system for producing a caieic acid-containing powder according to the present invention.

Explanation of symbols

1 Caic acid-containing powder production system

2 Processing container

3 Stirring means

4 Steam injection means

5 Pressure adjusting means

6 Control means

7 Silencer

9 Wastewater treatment equipment

10 Check valve

11 Control valve

12 Switching valve

21 Input port

22 outlet

23a Upper temperature sensor

23b Lower temperature sensor

24 Pressure sensor

31 Horizontal rotation axis

32 stirring blade

33 Drive motor

41 Boiler

42 Flue

43 Air supply valve

51 Pressure regulating valve

Claims

The scope of the claims

[1] Put rice husk or straw into a processing vessel, inject steam into the processing vessel to raise the internal pressure and temperature, and maintain the processing at a steam pressure at which the rice husk or straw powders without burning. And producing the powder containing caic acid.

[2] A method for producing a powder containing caic acid from rice hulls or straw, the method comprising:

It is characterized in that pressurized steam is injected into the rice husk or straw put into the processing vessel, and the pressure in the processing vessel is kept at 1.45MPa to 1.96MPa to perform powdering treatment. A method for producing a powder containing caic acid

[3] The method for producing a powder of citric acid according to claim 2, wherein the pressure in the processing container is maintained at 1.65 MPa to 1.85 MPa for 5 minutes to 30 minutes to perform powdering treatment.

[4] A processing vessel provided with a stirring means, steam injection means for injecting steam pressurized into the rice husk or straw put into the processing vessel, and rice hull or straw in the processing vessel burning And a control means for controlling the amount of water vapor injected by the water vapor injection means so as to maintain a pressure at which the powder can be drawn.

[5] A processing vessel provided with stirring means, steam injection means for injecting steam pressurized into the rice husks or straws charged into the processing vessel, and the amount of water vapor injected by the steam injection means And a control means for controlling the pressure in the processing vessel to be maintained at 1.45 MPa to 1.96 MPa.

[6] In claim 5, the control means controls a steam injection amount of the steam injection means such that a pressure in the processing vessel is maintained at 1.65 MPa-1.85 MPa for 5 minutes to 30 minutes. A production system for a powder containing caic acid, comprising: