JP3823152B2 - Charcoal manufacturing method and charcoal - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
TECHNICAL FIELD The present invention relates to a method for producing charcoal and charcoal, and more particularly, to a method for producing charcoal having a combustion rate adjusted or white coal derived from coniferous trees, and charcoal obtained by these production methods.
[0002]
[Prior art]
Conventionally, as charcoal, there are known so-called white charcoal using hardwood as a raw material as represented by Bincho charcoal and carbonizing at a high temperature, and so-called black charcoal using conifer as a raw material and carbonizing at a low temperature like cedar. Black charcoal has the characteristics that it is easy to catch fire, the burning speed is fast (burning time is short), and the combustion temperature is high. Contrary to white charcoal, it has the characteristics that it is difficult to catch fire, the combustion speed is slow (the combustion time is long: it burns slowly and slowly), and the combustion temperature is low.
[0003]
The carbonization process when making black charcoal will be described. First, make a charcoal kiln using suitable soil. Next, a raw material (carbon material) is packed in a charcoal kiln, carbonized at 350 ° C. to 400 ° C., and then heated to about 700 ° C. and refined. Then, the kiln opening vent is sealed, left to stand for 2-3 days, and then naturally cooled, and finally the kiln is opened and the coal is discharged.
[0004]
The carbonization process when making white coal will be described. First, make a charcoal kiln with stones on the wall and earth on the ceiling. Next, the raw material (carbon material) is packed in a charcoal kiln and carbonized at about 300 ° C. Subsequently, the kiln is widened little by little to raise the carbonization temperature to 900 ° C. to 1300 ° C. and thoroughly refine the raw material. Finally, scrub the incandescent thing little by little, cover with a little bit of pre-prepared antiseptic and cool.
[0005]
Conventionally, carbonization was performed as white charcoal for hardwoods and black charcoal for conifers.
[0006]
[Non-Patent Document 1]
Nobuhiko Ueda, Yasumasa Yonezawa, Tamio Kondo, “Wood Chemistry”, 1981, p. 61-95
[0007]
[Problems to be solved by the invention]
However, the conventional technique has the following problems.
In other words, Bincho charcoal, known as high quality charcoal, has a problem that its raw material is limited to hardwood Ubamegashi and it is difficult to secure the raw material. On the other hand, the wood species to be planted are coniferous trees such as cedar and cypress, and when thinned wood is used as charcoal, there are problems of excessive raw materials. In particular, coniferous charcoal, such as cedar and cypress, is for so-called black charcoal and has the problem of limited use.
[0008]
This invention is made | formed in view of the above, Comprising: It aims at providing the charcoal manufacturing method which can be adjusted to the charcoal which has the combustion characteristic according to a use.
[0009]
Moreover, it aims at making it possible to provide white charcoal using conifers.
[0010]
[Means for Solving the Problems]
[0012]
In order to achieve the above object, the charcoal production method according to claim 1 is a method of heating a conifer in a temperature range of 130 ° C to 230 ° C in a direction perpendicular to the annual rings so that the annual ring interval is shortened by rolling. while compressing the raw material its density was fixed an adjustment to the shape to be either ^{0.4g / cm 3 ~1.0g / cm 3} , a predetermined atmosphere maximum temperature is 800 ° C. to 1300 ° C. It is characterized by producing charcoal that is carbonized at a temperature and whose combustion rate is adjusted.
[0013]
That is, the invention according to claim 1 can be carbonized while the shape after heating and compression is fixed, and adjusts the size of the temporary canal and the canal of conifers to reduce the size of the macropores after carbonization. adjust. Thereby, the charcoal manufacturing method which can be adjusted to the charcoal which has the combustion characteristic according to a use can be provided. Examples of coniferous trees include cedar, cypress, cedar, cypress, pine (larch, black pine, bay pine), sawara, and hemlock. The temperature at the time of heat compression is preferably 130 ° C to 200 ° C, particularly preferably 160 ° C to 200 ° C. Density is ^{preferably 0.6g / cm 3 ~0.9g / cm 3} , which was adjusted to 0.8 g / cm ³ near 0.9 g / cm ³ is particularly preferred. A carbonization temperature of about 1000 ° C. or higher is particularly preferable.
[0014]
Moreover, the charcoal manufacturing method according to claim 2 is a method in which the volume of the charcoal is the original volume while being heated in a temperature range of 130 ° C. to 230 ° C. in a direction perpendicular to the annual rings so that the annual ring interval is shortened by rolling the conifers. The shape is fixed by compressing to 40% to 60%, and then the heat-compressed softwood is carbonized with the maximum temperature set to a predetermined atmospheric temperature of 800 ° C to 1300 ° C.
[0015]
That is, the invention according to claim 2 can increase the density of wood to the density of hardwood, adjust it to a raw material suitable for carbonization of white coal, and perform carbonization with the shape after heating and compression fixed. Thereby, it becomes possible to provide white charcoal using conifers. Examples of coniferous trees include cedar, cypress, pine (larch, black pine, and bay pine), sawara, and hemlock. The temperature at the time of heat compression is preferably 130 ° C to 200 ° C, particularly preferably 160 ° C to 200 ° C. The compression ratio is particularly preferably in the range of 50% to 60%. A carbonization temperature of about 1000 ° C. or higher is particularly preferable.
[0016]
Moreover, the charcoal according to claim 3 is manufactured by the charcoal manufacturing method according to claim 1 or 2.
[0017]
That is, the invention according to claim 3 can provide charcoal having combustion characteristics according to the use and white coal derived from conifers.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
Here, for convenience of various measurements, the coniferous raw material was heated and compressed, cut into a predetermined size, and then carbonized to prepare an evaluation sample. In addition, Bincho charcoal made from Umegamegashi was used as a comparative sample. In addition, cedar wood was used for the conifer. In the following, Bincho charcoal using Ubmegashi as a raw material will be appropriately referred to as Ubmegashi charcoal.
[0019]
FIG. 1 is a diagram showing a flow of manufacturing a charcoal raw material piece. As a raw material, cedar wood having a density of ρ = 0.34 g / cm ³ (1 g / cm ³ = 10 ³ kg / m ³ ), a moisture content of 10.4%, and an average annual ring width of 3.7 mm is used. The cross section was processed into a cedar square material having a width of 30 mm (width) x 300 mm (length) x 20 mm (height). Subsequently, it compressed in the perpendicular | vertical direction (radial direction) with respect to the annual ring with the heat roll type compression apparatus. The feed rate was 2.5 mm / s. In addition, in order to obtain a desired compression rate, the one that increased the compression rate was passed several times.
[0020]
2, a compression ratio CR, and a heating temperature (compression temperature) T _1, a diagram showing the density after heat compression. As shown in the drawing, in the production of compressed wood (charcoal raw material), compression rate CR = 0% to 75%, compression temperature T ₁ = 15 ° C. (normal temperature), 80 ° C., 130 ° C., 160 ° C., 180 ° C., 200 And 230 ° C. The compression ratio CR was obtained from the dimensional change in the radial direction.
[0021]
Dimensional recovery of compressed wood was confirmed after heat compression. The smaller the dimensional recovery, the easier it is to produce the desired charcoal, so the relationship between compression temperature and dimensional recovery was investigated. Figure 3 is a diagram showing a recovery rate for the compression ratio CR for each compression temperature T _1. 4 is a diagram showing a recovery rate for the compression temperature T ₁ of each compression ratio CR. From the figure, it was confirmed that the recovery rate was the lowest level when producing compressed wood at a high temperature, particularly when the compression temperature T ₁ ≧ 130 ° C. This is because when the compression temperature T ₁ is a high temperature, the microstructure of the wood, crystal fibrils around the cellulose surrounds lignin once loosened by the action of heat. Therefore, the cell wall constituted by the fibrils is easily bent by compression, and is fixed to the compressed shape by subsequent cooling. However, at a temperature where T ₁ is lower than 130 ° C., the structure of the fibril is difficult to loosen, and even when compressed, the change in the micro structure is small, so it is considered that the original shape is easily returned. In the following, the compression rate CR is displayed as a value after recovery.
[0022]
The obtained compressed wood was processed into a size of 20 mm (width) × 20 mm (length) to prepare a charcoal raw material piece. Next, the charcoal raw material pieces were carbonized using an ultra-high temperature rapid heating rapid cooling large capacity type thermobalance (manufactured by Vacuum Riko Co., Ltd .: TG-7000VHT). Carbonization temperature T ₂ = 400 ° C., 600 ° C., 800 ° C., and 1000 ° C. Process of carbonization, raised to carbonizing temperature T ₂ of the object in the first 10 minutes, the next 10 minutes maintaining the carbonized temperature T _2, the last 10 minutes was forced to cool to room temperature. Carbonization generally refers to a state where all wood gas components and distillate are produced. In this apparatus, it is possible to measure the mass change of the charcoal raw material piece during carbonization. Therefore, by measuring the mass of the raw material pieces during the carbonization process and confirming that the mass decreased within the carbonization time, it was assumed that all the wood gas components and distillate had been generated and defined as the end of carbonization. .
[0023]
(Evaluation of charcoal piece: hardness)
The hardness of the prepared piece of charcoal and the Bincho charcoal of Ubamegashi was measured. A durometer hardness tester was used for the measurement. The hardness was measured by pushing a needle into any five points of the charcoal piece. First, in order to make a comparison with Bunacho charcoal having a carbonization temperature of 1000 ° C., the relationship between the compression ratio CR and the hardness of the charcoal pieces having a carbonization temperature T ₂ of 1000 ° C. was examined. Figure 5 is a diagram carbonization temperature T ₂ is shows the relationship between compression ratio CR and hardness of charcoal pieces is 1000 ° C.. As apparent from the figure, be any compression temperature T _1, to the compression ratio of about 50% the hardness increases, the change in compression ratio hardness at around 50% was less. Moreover, from the figure, it was confirmed that the charcoal becomes the hardest around the compression temperature T ₁ = 180 ° C.
[0024]
Next, the relationship between the compression temperature T ₁ and the hardness of the charcoal piece having a carbonization temperature T ₂ of 1000 ° C. will be described. Figure 6 is a diagram carbonization temperature T ₂ is showing the relationship between compression temperatures T ₁ and hardness of charcoal pieces is 1000 ° C.. As is apparent from the figure, the hardness increased until the compression temperature T ₁ was about 180 ° C. at any compression ratio CR, but when the compression temperature T ₁ = 180 ° C. or more, the hardness suddenly increased. It was confirmed that it decreased. From the figure, as the level of compression the temperature _{T 1,} it can be said that preferably 130 ° C. to 200 DEG ° C., particularly preferably 160 ° C. to 200 DEG ° C..
[0025]
Then, changing the carbonization temperature T ₂ using a compression temperature T _{1 =} 180 ° C. charcoal material pieces were compared hardness of charcoal pieces. Figure 7 is a view showing the hardness to hydrocarbon temperature T ₂ for each compression ratio CR. It was confirmed that the hardness became harder as the compression ratio CR increased at any carbonization temperature. In particular, a high compression ratio (CR = 43% and 60%) is a charcoal material piece carbide temperature T _2, the higher the hardness of it was confirmed that the increase. This charcoal shrinkage occurs as the carbonization temperature T ₂ is higher, presumably because the density becomes high.
[0026]
Next, the relationship between the density and hardness of the charcoal fragments of the compression temperature T ₁ = 180 ° C. and the carbonization temperature T ₂ = 1000 ° C. was examined. FIG. 8 is a diagram showing the relationship between the density and hardness of charcoal fragments with a compression temperature T ₁ = 180 ° C. and a carbonization temperature T ₂ = 1000 ° C. As shown in the figure, it was confirmed that as the density of the raw charcoal pieces increased (high compression ratio), the hardness became harder, and approached to the Bincho charcoal of Umegashi. In addition, it turns out that the compression rate at the time of heat compression is suitable in the range of 40%-60% with 50% as a peak. It was also found that charcoal with a hardness close to that of Bincho charcoal can be produced even if the density is not as high as that of Umegashi.
[0027]
(Evaluation of charcoal fragments: combustion characteristics)
Next, the combustion characteristics of charcoal pieces and Bincho charcoal of Ubmegashi were measured. For the measurement, a thermal laboratory adiabatic calorimeter (manufactured by Yoshida Seisakusho) was used. The area around the charcoal piece was an oxygen atmosphere of 30 kgf / cm ² . In the measurement, the temperature was measured every 5 seconds until 2 minutes after the ignition of the charcoal piece, and thereafter every 10 minutes until 10 minutes. The reason why the water temperature was measured every 5 seconds until 2 minutes was that the temperature increase almost stopped in 1 minute and it was determined that combustion was terminated at this point. In the following figures, the calorific value of the charcoal piece itself is converted to the heat equivalent of the equipment as appropriate.
[0028]
FIG. 9 shows the combustion time t for each of cedar wood (no compression), charcoal fragments (compression ratio CR = 50%, compression temperature T ₁ = 180 ° C., carbonization temperature T ₂ = 1000 ° C.) It is the figure which showed the relationship of the emitted-heat amount Q. Since the combustion test of this study burned oxygen in a container filled with 30 kgf / cm ² , there was no sample left in the container after combustion, and the charcoal fragments can be tested under conditions that allow sufficient combustion. confirmed.
[0029]
FIG. 10 is a diagram comparing the combustion time t and the amount of heat generated per unit time with respect to the compression rate. It can be confirmed that as the compression ratio of the cedar compressed wood increases, the exothermic curve of the Binchocho charcoal of Ubamegashi approaches. In cedar wood and low-compression charcoal fragments (CR = 26%), the calorific value increased rapidly about 15 seconds after the start of combustion, and the peak was about 60 seconds later. In addition, the high compression rate charcoal fragments (CR = 50% to CR = 60%) and the Umegashi Bincho charcoal started to rise in temperature about 15 seconds after the start of combustion, but the low compression rate charcoal fragments (CR = 26%), it was confirmed that a gentle calorific value curve was drawn. The exothermic peaks of the cedar compressed wood (CR = 50% to CR = 60%) charcoal are all after about 78 seconds, the exothermic peak of Umegashi charcoal is after 85 seconds, and the exothermic peaks of both are close. It was confirmed that
[0030]
FIG. 11 is a graph showing the relationship between the raw material charcoal piece density and the maximum calorific value (Q _max / t) per unit time, and the raw charcoal piece density and the arrival time T _Qmax to the maximum calorific value Qmax. From the figure, as the density increases, Q _max / t decreases and the time T _Qmax to reach the maximum calorific value Q _max increases, becoming closer to the Bincho charcoal. On the other hand, as the density decreases, Q _max / t increases and the time T _Qmax to reach the maximum calorific value Q _max decreases, becoming closer to black charcoal (cedar charcoal). Incidentally, from the figure, by appropriately adjusting the density of ^{0.4g / cm 3 ~1.0g / cm 3} , it can be said that can adjust the burning rate or burning characteristics.
[0031]
As described above, according to the method for producing charcoal of the present invention, it was found that charcoal having an adjusted combustion rate can be produced by appropriately adjusting the compression rate in the heating and compressing step of the raw material member. The carbonization temperature of white coal may be raised to about 1300 ° C., and it goes without saying that the carbonization temperature T ₂ may be raised to about 1300 ° C. in the present invention as well.
[0032]
In this embodiment, the raw material wood is cedar, but conifers other than this may be used, and bamboo may be used in some cases. Even if coniferous trees are used, white charcoal can be produced in addition to conventional black charcoal, so it can be said that waste wood from demolition houses and thinned wood can be used effectively.
[0033]
【The invention's effect】
As described above, according to the present invention, it is possible to provide a charcoal production method that can be adjusted to charcoal having combustion characteristics in accordance with applications. Moreover, it was possible to provide white charcoal using conifers.
[Brief description of the drawings]
FIG. 1 is a diagram showing a flow of manufacturing a charcoal raw material piece.
[Figure 2] and the compression ratio CR, and a heating temperature (compression temperature) T _1, a diagram showing the density after heat compression.
3 is a diagram showing a recovery rate for the compression ratio CR for each compression temperature T _1.
FIG. 4 is a diagram showing a recovery rate with respect to a compression temperature T ₁ for each compression rate CR.
FIG. 5 is a graph showing the relationship between the compression ratio CR and hardness of a charcoal piece having a carbonization temperature T ₂ of 1000 ° C.
FIG. 6 is a graph showing the relationship between the compression temperature T ₁ and the hardness of a charcoal piece having a carbonization temperature T ₂ of 1000 ° C.
FIG. 7 is a diagram showing the hardness with respect to the carbonization temperature T ₂ for each compression ratio CR.
FIG. 8 is a diagram showing the relationship between the density and hardness of charcoal fragments with a compression temperature T ₁ = 180 ° C. and a carbonization temperature T ₂ = 1000 ° C.
FIG. 9 shows the combustion time t for each of cedar wood (no compression), charcoal fragments (compression ratio CR = 50%, compression temperature T ₁ = 180 ° C., carbonization temperature T ₂ = 1000 ° C.) It is the figure which showed the relationship of the emitted-heat amount Q.
FIG. 10 is a diagram comparing the combustion time t and the calorific value per unit time with respect to the compression rate.
FIG. 11 is a diagram showing the relationship between the raw charcoal piece density and the maximum calorific value (Qmax / t) per unit time, and the raw charcoal piece density and the arrival time T _Qmax to the maximum calorific value. .

Claims (3)

The conifer is compressed while being heated in a temperature range of 130 ° C. to 230 ° C. in a direction perpendicular to the annual rings so that the annual ring interval is shortened by rolling, and the density is 0.4 g / cm ^{3 to} 1.0 g / cm ^3. It is characterized by producing charcoal whose combustion rate is adjusted by carbonizing a raw material whose shape is adjusted so as to be any of the above at a predetermined atmospheric temperature whose maximum temperature is 800 ° C. to 1300 ° C. To make charcoal.   Shaped by compressing until the volume of the conifer is 40% to 60% of the original volume while heating in the temperature range of 130 ° C to 230 ° C in a direction perpendicular to the annual ring so that the annual ring interval is shortened by rolling. And then carbonizing the heat-compressed softwood with a maximum temperature of 800 ° C. to 1300 ° C. and a predetermined atmospheric temperature.   Charcoal produced by the method for producing charcoal according to claim 1 or 2.

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