JP2009270050A - Carbonization furnace - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a carbonization furnace superior in carbonization efficiency and carbonization product yield. <P>SOLUTION: A carbonization furnace 1 for organic waste includes a substantially cylindrical body 10 and a cylindrical material 20 housed in the body 10, and also a carbonization body 50 formed from the side wall of the body 10 and the cylindrical material 20 and used for carbonizing organic waste, and a non-combustion part 60 positioned below the carbonization part 50 and formed from the side wall of the body 10 and cylindrical material 20 and extinguishing burning of the carbonized organic waste; wherein the cylindrical material 20 has a double wall structure equipped with an inner wall and an air supply opening 23, and air is supplied from the air supply opening 23 to the carbonization part 50 through a preliminary heating chamber formed between the outer and inner walls. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a carbonization furnace, and more particularly to a carbonization furnace for carbonizing organic waste.

  In recent years, methods for treating organic substances (also referred to as “organic waste”) discharged from households and industrial fields and reusing them as charcoal have been studied. For example, Patent Document 1 includes a substantially cylindrical main body, and an upper space inside the main body is defined as a combustion zone in which combustible gas generated from organic waste is mainly combusted. A space formed by an upper portion of the cylindrical body and a side wall of the main body is formed as a refining zone for burning organic waste and carbonizing by the heat of combustion, and the upper portion of the cylindrical body Disclosed is a carbonization furnace characterized in that a space constituted by a portion other than the main body and a side wall of the main body is formed as a non-combustible zone for creating a non-combustible state and extinguishing the carbide, and supplying air from the cylindrical body to the combustion zone Has been. This carbonization furnace is said to be able to make the combustion temperature uniform by supplying air from a cylindrical body, shorten the refining time, and improve the quality of charcoal.

However, the carbonization furnace described in the document has not yet sufficient carbonization efficiency and carbide yield expressed by the carbide yield per hour, and further improvement has been demanded.
JP 2000-17269 A

The inventors have studied the carbonization furnace described in Patent Document 1 in order to improve the carbonization efficiency and the carbide yield. As a result, it has been found that if the temperature of the atmosphere in which the organic waste is carbonized is lowered by the air blown from the cylindrical body, the carbonization efficiency and the carbide yield are lowered.
In view of such circumstances, an object of the present invention is to provide a carbonization furnace having excellent carbonization efficiency and carbide yield.

[1] An organic waste carbonization furnace including a substantially cylindrical main body and a cylindrical body accommodated in the main body,
A carbonized portion that is formed by the side wall of the main body and the cylindrical body, and carbonizes organic waste,
Located below the carbonized part, formed by the side wall of the main body and the cylindrical body, and comprising a non-combustible part that extinguishes the carbonized organic waste,
The cylindrical body has a double wall structure having an inner wall and an outer wall having an air supply port, and air is supplied from the air supply port through a preheating chamber formed between the outer wall and the inner wall. To supply the carbonization furnace.
[2] The carbonization furnace according to [1], wherein the inner wall of the cylindrical body has an air inlet to the preheating chamber outside a region facing the air supply port provided in the outer wall.
[3] The carbonization furnace according to [1] or [2], wherein a width of a space between the outer wall and the inner wall forming the preheating chamber of the cylindrical body is 100 to 200 mm.
[4] The carbonization furnace according to any one of [1] to [3], wherein an upper portion of the cylindrical body has a truncated cone shape, and a side surface of the truncated cone includes the air supply port.
[5] The carbonization furnace according to any one of [1] to [4], wherein the wall of the main body located in the carbonization unit includes an air supply port.
[6] The carbonization furnace according to any one of [1] to [5], wherein the cylindrical body is removable from a bottom portion of the main body.
[7] The carbonization furnace according to any one of [1] to [6], wherein a width of a space formed between the side wall of the main body and the cylindrical body is 400 to 600 mm.

  According to the present invention, a carbonization furnace excellent in carbonization efficiency and carbide yield can be provided.

1. Carbonization furnace The carbonization furnace of the present invention is a carbonization furnace for organic waste, and includes a substantially cylindrical main body and a cylindrical body accommodated in the main body. The carbonization furnace of the present invention is formed by the side wall of the main body and the cylindrical body, and is formed by the carbonization portion that carbonizes organic waste, the carbonization portion located below the carbonization portion, and the side wall of the main body and the cylindrical body. And an incombustible portion for extinguishing the carbonized organic waste. The cylindrical body has a double wall structure having an outer wall with an inner wall and an air supply port, and air is supplied from the air supply port to the carbonization part via a preheating chamber formed between the outer wall and the inner wall. It is characterized by supplying.

  Organic waste is waste containing carbon. Examples include food waste, construction waste, shredder dust, livestock waste, thinned wood, pruned branches, sawdust, wood and wood waste such as bamboo and cut grass, soft biomass such as sludge and inawara, This includes general waste discharged from households. Among them, wood waste materials (also referred to as “woody biomass”) are preferable as organic waste.

  It is preferable that the organic waste is previously dried with a drier or the like and the water content thereof is appropriately adjusted. This is because the carbonization efficiency and the carbide yield can be increased. The moisture content is preferably 10 to 30%. In the present invention, the symbol “˜” includes numerical values at both ends thereof.

FIG. 1 is a cross-sectional view showing an example of a carbonization furnace of the present invention. As shown in FIG. 1, the carbonization furnace 1 mainly includes a main body 10 and a cylindrical body 20 accommodated in the main body 10 (the cylindrical body 20 is shown in a front view).
The main body 10 has an input port 11 for organic waste, an exhaust port 12, an ignition burner 13, an air supply port 14, and an outlet 15. The upper portion of the cylindrical body 20 has a truncated cone shape, and has an air supply port 23 on a side surface (also referred to as “top wall” 21) and a side wall 22 of the truncated cone shape. Each material will be described below with reference to FIGS.

(1) Main body The main body 10 has a substantially cylindrical shape. The substantially cylindrical shape refers to a cylinder or a shape similar to this. The main body 10 has an inlet 11 for organic waste. Waste is introduced into the carbonization furnace 1 from here. The main body 10 preferably has an ignition burner 13 and an air supply port 14 for burning the introduced organic waste. The ignition burner 13 may be provided at any position as long as the organic waste can be ignited, but is preferably provided slightly below the charging port 11. The organic waste is burned here to produce solids rich in carbides and cracked gas.

The air supply port 14 is preferably provided at a position below the charging port 11 on the side wall of the main body 10, and is provided at a “position facing the region where the air supply port 23 of the cylindrical body 20 is provided” on the side wall of the main body 10. More preferably. Furthermore, the air supply port 14 is preferably provided over the entire circumference of the main body 10. The air supply port 14 is preferably a circular hole, and its diameter is preferably about 10 to 30 mm.
Organic matter is burned to produce solids rich in carbides. This solid content containing a large amount of carbide reaches the region formed by the side wall of the main body 10 and the cylindrical body 20. In this region, the solids rich in carbides are further carbonized. This region is called the carbonized portion 50. The carbonization in the carbonization part 50 means that the carbonization proceeds while maintaining the high temperature while supplying air. This carbonization is also called “refining” or “storm”.

  An incombustible portion 60 is formed in a region sandwiched between the side wall of the main body 10 and the cylindrical body 20 below the carbonized portion 50. Carbides refined in the carbonization part 50 are transferred to the non-combustible part 60. Since the carbide immediately after reaching the incombustible portion 60 is still burning, the incombustible portion 60 blocks the air and extinguishes the fire.

  It is preferable that a space for burning the decomposition gas generated when the organic waste is burned is formed in the upper part of the main body 10. This space is also called a secondary combustion unit 70.

  It is preferable that the bottom of the main body 10 is provided with an outlet 15 for taking out the carbide extinguished by the incombustible portion 60.

  The size of the main body 10 may be appropriately selected according to the amount of organic waste to be treated and the amount of carbide to be produced, but the diameter is preferably 0.5 to 3 m. The height of the main body 10 is preferably 1 to 4 m. Moreover, the material which comprises the main body 10 should just be a well-known material, and stainless steel is contained in the example of a well-known material.

(2) Cylindrical body The carbonization furnace 1 of the present invention has a cylindrical body 20 accommodated in the main body 10. The cylindrical body is a columnar member and plays a role like a so-called “baked ball” in the carbonization furnace 1 of the present invention. That is, the cylindrical body 20 heats the carbonization part 50 to promote carbonization. The cylindrical body 20 may be provided with a heating device, but the cylindrical body 20 is preferably heated by heat or the like when burning organic waste.

  As for the cylindrical body 20, as shown in FIG. 1, it is preferable that an upper part is a truncated cone shape. With this structure, the upper part of the carbonization part 50 can be widened, and it becomes easy to introduce into the carbonization part 50 a solid content containing a large amount of carbides obtained by burning organic waste.

  As shown in FIG. 2, the cylindrical body 20 has a double wall structure having an inner wall 26 and an outer wall 24, and has a preheating chamber 25 formed between the outer wall 24 and the inner wall 26. FIG. 2 is a sectional view showing an outline of the cylindrical body 20. An air supply port 23 is provided in the outer wall 24, and an air introduction port 28 is provided in the inner wall 26. A space 27 formed in the inner wall 26 communicates with an air supply port 29 provided in the shaft 35.

  Air introduced from the air inlet 29 is introduced from the air inlet 28 into the preheating chamber 25. Heat generated by burning organic waste is transmitted from the outer wall 24 to the preheating chamber 25, and the air introduced into the preheating chamber 25 is heated. Since the preheating chamber 25 is shielded from the space 27 by the inner wall 26, heat is not easily transmitted to the space 27, and air can be efficiently heated. The air heated in the preheating chamber 25 is supplied to the carbonization unit 50 (FIG. 1) through the air supply port 23. Thus, since the air heated previously is sent into the carbonization part 50, atmospheric temperature is not reduced. For this reason, the carbonization part 50 can perform carbonization efficiently.

The width t (also referred to as “width t of the preheating chamber 25”) between the outer wall 24 and the inner wall 26 is preferably about 150 to 300 mm. This is because air can be efficiently heated.
The air introduction port 28 provided in the inner wall 26 is preferably provided outside the region facing the air supply port 23 provided in the outer wall 24. For example, in FIG. 2, the air supply port 23 and the air introduction port 28 in the outer wall 24 are provided so as not to line up on the horizontal line. Thus, if the air flow path is complicated, the time during which the air stays in the preheating chamber 25 can be lengthened, and the air can be sufficiently heated. The shape of the air inlet 28 is preferably the same as that of the air supply port 14 provided in the main body 10.

  As shown in FIG. 1, the air supply port 23 is preferably provided in the upper part of the cylindrical body 20 and is not provided in the lower part of the cylindrical body 20. Thereby, the incombustible part 60 by which air was interrupted | blocked is formed in the part enclosed by the lower part of the cylindrical body 20, and the side wall of the main body 10 which opposes. The upper part of the cylindrical body 20 refers to the upper part of the top wall 21 or the side wall 22. It is preferable that the air supply port 23 is provided over the entire circumference of the top wall 21 or the side wall 22. The top wall 21 refers to the side surface of the truncated cone portion of the cylindrical body 20. In particular, it is preferable to provide the air supply port 23 in the top wall 21 because the organic waste is easily burned immediately after being charged from the charging port 11 and the carbonization in the carbonization part 50 is also facilitated.

The ratio of “height of the portion where the air supply port 23 is provided” and “height of the portion where the air supply port 23 is not provided” in the side wall 22 is 0.5 or more for the latter with respect to the former 1. Is preferred. This is because the carbide can be surely extinguished.
The shape of the air supply port 23 is preferably the same as that of the air supply port 14 provided in the main body 10.
It is desirable that the top surface of the cylindrical body 20 is located 100 to 200 mm, preferably about 150 mm above the air supply port 14 provided in the main body 10.

  The cylindrical body 20 is preferably rotatable about a vertical passing through the bottom surface of the cylindrical body 20 and the center of the ceiling surface. When the cylindrical body 20 is rotatable in this way, air can be fed more uniformly into the carbonizing portion 50, the carbonization efficiency can be improved, and the purity of the carbide can be improved. The means for rotating the cylindrical body 20 is not limited, but it is preferable to connect the cylindrical body 20 to the shaft 35 and rotate the shaft 35 by a known driving means.

  As shown in FIG. 1, the bottom of the cylindrical body 20 preferably includes a table 30. The table 30 is preferably frustoconical, and can be moved up and down, and the distance from the main body 10 can be adjusted as appropriate. This is because the carbide can be pulverized between the table 30 and the main body 10 and the size of the carbide can be appropriately adjusted. The table 30 is preferably rotatable. The table 30 may rotate in conjunction with the cylindrical body 20, but may be rotatable independently of the cylindrical body 20. Known means are used for the lifting means and rotating means of the table 30.

  The cylindrical body 20 is preferably removable from the bottom of the main body 10. In the carbonization furnace 1, there may be a clinker formed mainly by cooling molten silica. Since the clinker may impair the performance of the carbonization furnace 1, it needs to be removed periodically. Since the carbonization furnace 1 of the present invention can increase the width w of the carbonization part 50 and the incombustible part 60 and improve the yield of carbide as described later, the amount of clinker to be generated may increase. At this time, if the cylindrical body 20 is removable from the bottom of the main body 10, the clinker removal operation is facilitated. The structure for removing the cylindrical body 20 from the bottom of the main body 10 is not limited, but a structure as shown in FIG. 3 is preferable. FIG. 3 is a cross-sectional view of the vicinity of the bottom of the carbonization furnace 1 of the present invention (however, the cylindrical body 20 and the table 30 are front views). The table 30 is in contact with the bottom 18 of the main body 10. The bottom portion 18 can be separated by a separation portion 19 provided at a lower portion of the side wall of the main body 10. That is, the separating part 19 is normally connected by a connecting device (not shown), but when repairing or the like, the bottom 18 can be separated from the main body 10 by releasing the connecting device. The table 30 and the cylindrical body 20 can be taken out from the bottom of the main body 10 from which the bottom 18 has been cut off.

The size of the cylindrical body 20 is not limited, but the diameter d is preferably about 400 to 800 mm. The height h of the cylindrical body 20 is preferably about 800 m to 1500 mm.
Further, the width w of the space formed between the side wall of the main body 10 and the cylindrical body 20 (corresponding to the carbonized portion 50 and the incombustible portion 60) may be arbitrary, but is preferably 400 to 600 mm, more preferably 450 to 600 mm, More preferably, it is 500-550 mm. In the conventional carbonization furnace, the width is often 350 to 400 mm. If the width is larger than this, it is not possible to sufficiently supply air to the organic waste, so that the carbonization efficiency is lowered. If the width is smaller than this, the yield of the carbide is lowered. However, since the carbonization furnace of the present invention can supply sufficiently preheated air to the carbonization section 50, even if the width is made larger than the conventional one, the carbonization efficiency is unlikely to decrease. Therefore, both carbonization efficiency and carbide yield can be improved.
A known material may be used as the material constituting the cylindrical body 20. Examples of known materials include stainless steel.

2. Manufacturing method The manufacturing method of the carbide | carbonized_material using the carbonization furnace of this invention is (1) The process of throwing in organic waste into a carbonization furnace, (2) The process of burning and carbonizing organic waste, (3) Carbonized organic It is preferable to include a step of extinguishing the waste and (4) a step of taking out the carbide. Below, the manufacturing method of the carbide | carbonized_material using the carbonization furnace of this invention is demonstrated concretely using FIG.

(1) Input process In this process, organic waste is input into the carbonization furnace 1 from the input port 11. It is preferable to use those already mentioned as the organic waste. The organic waste may be dried. The means for introducing the organic waste is not limited, but it is preferable to add it quantitatively and periodically using, for example, a screw feeder or a table feeder.

(2) Combustion / carbonization process In this process, the organic waste that is input is burned. Specifically, it is preferable that the organic waste is ignited by the ignition burner 13 and the organic waste is combusted by supplying air from the air supply port 23 of the cylindrical body 20 into the carbonization furnace 1. In addition, a heater may be installed in the carbonization furnace 1 so that the organic waste is heated to the ignition point and burned.

  In this step, the organic waste is burned to obtain “solids rich in carbides” and “pyrolysis gas”. The pyrolysis gas is a mixed gas containing carbon monoxide, hydrogen, hydrocarbons, sulfur oxides, nitrogen oxides and the like. The solid content containing a large amount of carbide moves to the carbonization section 50, and the pyrolysis gas moves to the secondary combustion section 70 above the carbonization furnace 1 and burns. The heat obtained by this combustion can also be used for heating the cylindrical body 20 and for burning and carbonizing newly introduced organic waste.

  On the other hand, since the “solid content containing a large amount of carbides” contains pyrolysis gas, if the fire is extinguished as it is, impurities contained in the carbides increase, and the yield of carbides may be reduced. Therefore, in the present invention, in the carbonization unit 50, the preheated air is supplied from the air supply port 23 of the cylindrical body 20, and the pyrolysis gas contained in the solid content containing a large amount of carbides is combusted. Carbonization is further advanced. That is, the above-described “refining” can be performed efficiently. Therefore, in the present invention, it is possible to remove the “pyrolysis gas contained in solid matter” which is generally difficult to remove, and a high-purity carbide can be obtained in a high yield. At this time, it is preferable to rotate the cylindrical body 20 because it can proceed more uniformly than refining.

  In this step, it is preferable that the temperature in the vicinity of the inlet 11 and the secondary combustion part 70 is 800 to 1000 ° C., and the temperature of the carbonization part 50 is about 600 to 800 ° C. In addition, it is preferable to set the residence time of the pyrolysis gas in the secondary combustion section 70 to 2 seconds or more because generation of dioxins can be reduced. The temperature of each part can be adjusted by the amount of air supplied into the carbonization furnace 1.

(3) Fire extinguishing process The carbide obtained by sufficiently carbonizing the solid in the carbonization part 50 subsequently reaches the incombustible part 60. The carbide that has just reached is still burning. In this step, the carbide is extinguished by shutting off the supply of air to the carbide. However, it is difficult to completely block air in this process. Therefore, when the temperature of the carbide is equal to or higher than the ignition temperature, the carbide continues to burn, and the carbide yield may be reduced. Therefore, this step is preferably performed at a temperature lower than the ignition temperature. In order to make the incombustible portion 60 lower than the ignition temperature of the carbide, as described above, the “height of the portion where the air supply port 23 is provided” and the “height of the portion where the air supply port 23 is not provided” of the side wall 22 The ratio of the former 1 to the former 1 is preferably 0.5 or more.

(4) Extraction step In this step, the carbides present in the incombustible portion 60 are extracted from the outlet 15. In many cases, carbides are aggregated into a lump. Therefore, when the gap between the table 30 and the main body 10 is adjusted to an appropriate value and the table 30 is rotated, the agglomerated carbide can be pulverized to a desired size.

A carbonization furnace 1 shown in FIG. The main body 10 of the carbonization furnace 1 has a cylindrical shape with a diameter of 1 m and a height of 2.5 m. The cylindrical body 20 accommodated in the main body 10 was a cylinder having a diameter of 600 mm, and the upper part was a truncated cone. The height of the cylindrical body 20 was 800 mm.
When waste wood having a water content of 20% by mass was put into a carbonization furnace and carbonized by the method described above, it was confirmed that high-purity carbide was obtained with a yield of 25-27%. Since the theoretical carbide yield of wood having a moisture content of 20% by mass is 29.6%, it is clear that the present invention can provide a carbide with a high yield. Moreover, the processing efficiency of the waste wood used as the scale of the carbonization efficiency in this example was about 1 t per hour.

  Since the carbonization furnace of the present invention is excellent in carbonization efficiency and carbide yield, it is useful as a carbonization furnace for organic waste.

Sectional drawing which shows the outline | summary of the carbonization furnace of this invention Sectional view showing the outline of the cylinder Sectional drawing which shows the bottom part vicinity of the carbonization furnace of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Carbonization furnace 10 Main body 11 Input port 12 Exhaust port 13 Ignition burner 14 Air supply port 15 Outlet 18 Bottom part 19 Separation part 20 Cylindrical body 21 Top wall 22 Side wall 23 Air supply port 24 Outer wall 25 Preheating chamber 26 Inner wall 27 Space 28 Air introduction port 29 Air supply port 30 Table 35 Shaft 50 Carbonization part 60 Non-combustion part 70 Secondary combustion part d Diameter of cylindrical body 20 t Width of preheating chamber 25 w Formed between side wall of main body 10 and cylindrical body 20 Width of space

Claims (7)

An organic waste carbonization furnace including a substantially cylindrical main body and a cylindrical body accommodated in the main body,
A carbonized portion that is formed by the side wall of the main body and the cylindrical body, and carbonizes organic waste,
Located below the carbonized part, formed by the side wall of the main body and the cylindrical body, and comprising a non-combustible part that extinguishes the carbonized organic waste,
The cylindrical body has a double wall structure having an inner wall and an outer wall having an air supply port, and air is supplied from the air supply port through a preheating chamber formed between the outer wall and the inner wall. To supply the carbonization furnace.   2. The carbonization furnace according to claim 1, wherein an inner wall of the cylindrical body has an air introduction port to a preheating chamber outside a region facing an air supply port provided in the outer wall.   The carbonization furnace according to claim 1, wherein a width of a space sandwiched between an outer wall and an inner wall forming the preheating chamber of the cylindrical body is 100 to 200 mm.   2. The carbonization furnace according to claim 1, wherein an upper portion of the cylindrical body has a truncated cone shape, and a side surface of the truncated cone is provided with the air supply port.   The carbonization furnace according to claim 1, wherein a wall of the main body located in the carbonization portion includes an air supply port.   The carbonization furnace according to claim 1, wherein the cylindrical body is removable from a bottom portion of the main body.   The carbonization furnace according to claim 1, wherein a width of a space formed between the side wall of the main body and the cylindrical body is 400 to 600 mm.

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