JP2010159897A - Wood drying device and method of drying wood - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wood drying device and a method of drying wood capable of preventing a change of a color of wood after being dried. <P>SOLUTION: The wood drying device 1 includes a drying furnace 11, and a boiler 12 for supply hot air into the drying furnace 11. In the drying furnace 11, a wood powder layer 22 is formed in a state of covering the whole face of the wood 100 as a drying object, and the boiler 12 supplies hot air into the drying furnace 11 so that the hot air passes in the wood powder layer 22 from a lower part to an upper part. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a wood drying apparatus and a wood drying method for drying wood.

  Wood drying methods can be broadly classified into natural drying and artificial drying. Among them, the natural drying causes problems such as a long period of time for drying and deformation such as twisting as a result of drying. Therefore, in recent years, artificial drying has been widely performed.

  For example, a wood drying method for forcibly drying the wood by sending hot air into the drying furnace using a burner or the like and exposing the wood contained in the drying furnace to the hot air has been performed ( For example, see Patent Documents 1 and 2.) Thereby, it becomes possible to dry a timber in a short time compared with the case of natural drying.

JP-A-6-2135666 JP-A-11-63823

  However, in the case of the conventional wood drying method as described above, in the drying process, components in the wood such as lignin and tannin ooze out to the surface layer portion of the wood, and as a result, the surface layer portion of the wood turns brownish brown. There was a problem.

  This invention is made | formed in view of such a situation, The main objective is to provide the wood drying apparatus and wood drying method which can solve the said subject.

  In order to solve the above-described problem, a wood drying apparatus according to an aspect of the present invention includes a drying furnace and a hot air supply unit that supplies hot air into the drying furnace, and the drying furnace includes a drying process. A wood powder layer is provided so as to cover the entire surface of the target wood, and the hot air supply unit supplies hot air into the drying furnace so that the hot air passes through the wood powder layer from below to above. It is configured.

  If comprised in this way, since the wood flour of a wood powder layer can absorb the water | moisture content of the wood of drying object, drying of wood is accelerated | stimulated. Moreover, the wood flour layer can absorb the components in the wood that change the color of the wood to brown, so that it is possible to prevent the wood after drying from turning brown.

  In the wood drying apparatus according to the above aspect, a wood chip layer formed by arranging a plurality of wood chips arranged below the wood powder layer is provided in the drying furnace, and the hot air supply unit is configured to supply hot wood to the wood chips. It may be configured to supply hot air into the drying furnace so as to pass through the layer and the wood powder layer from below to above.

  Further, in the wood drying apparatus of the above aspect, the wood chip layer is formed by arranging the wood chips on a mesh material that allows air to pass without passing through the wood chips, and the hot air supply unit is configured such that hot air is the mesh material, You may be comprised so that a hot air may be supplied in the said drying furnace so that the inside of a wood chip layer and the said wood powder layer may pass upwards from the downward direction.

  Moreover, in the wood drying apparatus of the said aspect, the talc may be contained in the said wood powder layer.

  In the wood drying method of one aspect of the present invention, the wood to be dried is placed in a wood powder layer provided in a drying furnace, the entire surface of the wood is covered with wood powder, hot air is generated, The wood is dried by passing through the wood powder layer from below to above.

  In the wood drying method of the above aspect, a wood chip layer is provided in the drying furnace, which is located under the wood powder layer and in which a plurality of wood chips are arranged, generates hot air, and the wood chip layer and The wood may be dried by passing through the wood powder layer from below to above.

  Further, in the wood drying method of the above aspect, the wood chip layer is formed by arranging the wood chips on a mesh material that allows air to pass without passing through the wood chips, and generates hot air to generate the mesh material and the wood chips. The wood may be dried by passing through a layer and the wood powder layer from below to above.

  Moreover, in the wood drying method of the said aspect, the talc may be contained in the said wood powder layer.

  According to the wood drying apparatus and the wood drying method according to the present invention, discoloration of wood after drying can be prevented.

The sectional side view which shows the structure of the wood drying apparatus of Embodiment 1 of this invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front sectional view showing a configuration of a wood drying apparatus according to a first embodiment of the present invention. The front sectional view which shows the structure of the wood drying apparatus of Embodiment 2 of this invention.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is a side sectional view showing a configuration of a wood drying apparatus according to Embodiment 1 of the present invention. FIG. 2 is a front sectional view showing the configuration of the wood drying apparatus.
As shown in FIGS. 1 and 2, the wood drying apparatus 1 according to the present embodiment includes a box-shaped drying furnace 11 having a length that can accommodate the wood 100 to be dried, and hot air in the drying furnace 11. A boiler 12 to be supplied and an exhaust pipe 13 for discharging the air in the drying furnace 11 to the outside are provided.

  Inside the drying furnace 11, a mesh sheet 21 attached and fixed to the inner wall of the drying furnace 11 and a wood powder layer 22 provided on the mesh sheet 21 are provided. Here, the wood powder layer 22 is a layer made of wood powder having an average particle diameter of about 1 mm to 3 mm.

  The mesh sheet 21 has a plurality of openings having a size that does not allow the wood powder constituting the wood powder layer 22 to pass therethrough. A wood powder layer 22 is formed by supplying and depositing wood powder on the mesh sheet 21.

  In addition, the average particle diameter of the wood flour of the wood flour layer 22 is not limited to the above, and even if it is smaller (for example, smaller than 1 mm and 300 μm or more) or larger (for example, larger than 3 mm and 5 mm) The following etc. are good. The wood powder may be commercially available or may be generated from a sawmill, a woodworking plant, or the like.

  The thickness of the wood powder layer 22 only needs to be larger than the thickness of the wood 100 to be dried. The wood 100 is embedded in the wood powder layer 22 so that the entire surface is covered with the wood powder of the wood powder layer 22.

  In addition, the wood 100 embedded in the wood powder layer 22 may be one or plural. When burying a plurality of timbers 100, as shown in FIGS. 1 and 2, the entire surface of all the timbers 100 is covered with wood flour by arranging them at a predetermined distance in the vertical and horizontal directions. It is desirable to do so.

  In the case of the present embodiment, since the arrangement of the timber 100 is fixed by the wood flour in the wood flour layer 22, even if the timbers 100 are arranged in the vertical direction, a crosspiece or the like is unnecessary. When using a pier, etc., there may be inconveniences such as discoloration of the part that contacts the pier in the wood to be dried, but in this embodiment, it is not necessary to use a pier, etc., so such an inconvenience occurs. Absent.

  Note that a door (not shown) of a predetermined size is attached to the drying furnace 11 so as to be openable and closable, and the wood 100 to be dried is carried in and out through the door.

  The boiler 12 is connected to a pipe 16 through which hot air flows, and the pipe 16 communicates with a lower part on the front side of the drying furnace 11. Hot air generated by the boiler 12 is sent into the air layer 14 formed between the mesh sheet 21 and the bottom wall of the drying furnace 11 via the pipe 16. The hot air thus sent into the air layer 14 rises in the air layer 14, passes through the mesh sheet 21 and the wood powder layer 22, and is between the wood powder layer 22 and the ceiling wall of the drying furnace 11. It flows to the air layer 15 to be formed.

  In the present embodiment, the pipe 16 communicates with the lower part on the front side of the drying furnace 11, but the present invention is not limited to this mode, and any other hot air can be fed into the air layer 14 as described above. The aspect of this may be sufficient.

  The exhaust tube 13 is provided on the upper surface of the drying furnace 11 and communicates with the inside of the drying furnace 11. As described above, the hot air that has passed through the air layer 14, the mesh sheet 21, and the wood powder layer 22 and has flowed into the air layer 15 is discharged to the outside of the drying furnace 11 through the exhaust tube 13.

  Instead of providing the exhaust tube 13 in this way, for example, the ceiling surface of the drying furnace 11 may be opened, and thereby the hot air may be discharged out of the drying furnace 11.

  When wood is dried by the wood drying apparatus 1 configured as described above, hot air is supplied from the boiler 12 so that the atmosphere in the air layer 14 is about 150 ° C. to 180 ° C. Note that the appropriate temperature varies depending on the type of wood 100 to be dried, and for example, a temperature lower than the above is sufficient in the case of wood that is easy to dry. Further, if the drying time is lengthened, the temperature may be lower. On the other hand, if the drying time is shortened, it is necessary to set a higher temperature. When the temperature is about 150 ° C. to 180 ° C., the drying time is preferably about 2 days.

  The hot air sent from the boiler 12 to the air layer 14 in the drying furnace 11 rises in the air layer 14 and passes through the mesh sheet 21 and the wood powder layer 22. Thereby, heat is applied to the wood 100 embedded in the wood powder layer 22, and as a result, drying of the wood 100 proceeds. At this time, the wood powder in the wood powder layer 22 absorbs the moisture that has escaped from the wood 100, so that the drying of the wood 100 is promoted. Moreover, since wood flour absorbs components in the wood 100 such as lignin and tannin together with moisture, it is possible to prevent lignin and tannin and the like from accumulating in the surface layer portion of the wood 100 after drying. Therefore, the surface layer part of the wood 100 after drying can maintain the white state before drying without changing to brown.

  In addition, you may mix a talc with the wood powder layer 22 in order to improve thermal conductivity. By mixing talc in this way, heat can be easily transmitted to the wood 100 embedded in the wood powder layer 22, so that the drying time can be shortened. As the talc mixed in the wood powder layer 22, for example, those manufactured by Nippon Talc Co., Ltd. can be used.

  If the amount of talc in the wood powder layer 22 is too large, the wood powder will not sufficiently absorb components such as lignin and tannin. On the other hand, if the amount of talc in the wood powder layer 22 is too small, the effect of increasing the thermal conductivity is not achieved. Therefore, it is desirable to mix talc into the wood flour layer 22 in the range of about 1 to 10 weight percent.

  In addition, even when, for example, calcium carbonate, magnesium oxide, sand, ceramic grains, or the like is used instead of talc, it is possible to increase thermal conductivity. Therefore, these calcium carbonates and the like may be mixed in the wood powder layer 22 in place of or together with talc.

(Embodiment 2)
The wood drying apparatus according to Embodiment 2 includes a wood chip layer made of wood chips, and a wood powder layer is provided thereon.
FIG. 3 is a front sectional view showing the configuration of the wood drying apparatus according to Embodiment 2 of the present invention. As shown in FIG. 3, inside the drying furnace 11 provided in the wood drying apparatus 2 of the present embodiment, a mesh sheet 31 attached and fixed to the inner wall of the drying furnace 11, and provided on the mesh sheet 31. A wood chip layer 32 and a wood powder layer 22 provided on the wood chip layer 32 are provided.

  The wood chip layer 32 is formed by placing a plurality of wood chips 33 side by side on the mesh sheet 31. As this wood chip 33, a commercially available wood chip having a width or diameter of about 20 mm to 70 mm and a thickness of about 5 mm to 20 mm can be used. In addition, since there is no problem even if the size of the wood chip 33 varies, the crushed pieces of wood generated at the sawmill and the woodworking plant can be used as they are.

  The wood powder layer 22 is formed by supplying and depositing wood powder on the wood chip layer 32 described above. When wood powder is supplied onto the wood chip layer 32, the wood powder is filled in the gaps between the wood chips 33 in the wood chip layer 32. Then, the wood powder is deposited on the wood chip layer 32 thus filled with the wood powder, and as a result, the wood powder layer 22 is formed.

  The mesh sheet 31 has a plurality of openings of a size that does not allow the wood chips 33 of the wood chip layer 32 to pass therethrough. Therefore, the opening of mesh sheet 31 can be made larger than the opening of mesh sheet 21 in the first embodiment. Therefore, compared with the mesh sheet 21, the mesh sheet 31 can pass hot air rising from below more rapidly.

  Hot air generated by the boiler 12 is sent into the air layer 34 formed between the mesh sheet 31 and the bottom wall of the drying furnace 11 via the pipe 16. The hot air thus sent into the air layer 34 rises in the air layer 34, passes through the mesh sheet 31, the wood chip layer 32 and the wood powder layer 22, and passes through the wood powder layer 22 and the ceiling of the drying furnace 11. It flows to the air layer 15 formed between the walls.

  In addition, about the other structure of the wood drying apparatus 2 of this Embodiment, since it is the same as that of the case of Embodiment 1, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  When the wood drying apparatus 2 configured as described above is used to dry the wood, as in the case of the first embodiment, the hot air from the boiler 12 is adjusted so that the atmosphere in the air layer 34 is about 150 ° C. to 180 ° C. Is supplied.

  The hot air sent from the boiler 12 to the air layer 34 in the drying furnace 11 rises in the air layer 34 and passes through the mesh sheet 31, the wood chip layer 32, and the wood powder layer 22. As a result, heat is applied to the wood 100 embedded in the wood powder layer 22, and the drying of the wood 100 proceeds.

  As described above, the mesh sheet 31 can pass hot air more quickly than the mesh sheet 21 in the first embodiment. Therefore, in the wood drying apparatus 2 of the present embodiment, heat can be transferred to the wood 100 in the wood powder layer 22 faster than in the case of the first embodiment, so that the drying of the wood 100 is further promoted. be able to.

(Other embodiments)
In each of the above embodiments, hot air is supplied into the drying furnace by the boiler, but the present invention is not limited to this. For example, a configuration may be adopted in which a burner is attached to the drying furnace, hot air is generated by a flame emitted from the burner, and this is sent into the drying furnace.

  Further, in the first embodiment, the mesh sheet 21 is used to form the wood powder layer 22, and in the second embodiment, the mesh sheet 31 is used to form the wood chip layer 32. Any member that allows hot air to pass through without passing through the wood chips may be used, and other mesh materials may be used.

  It should be noted that the above embodiments can be appropriately combined.

  The wood drying apparatus and the wood drying method of the present invention are useful as a wood drying apparatus and a wood drying method for drying wood such as square wood, respectively.

DESCRIPTION OF SYMBOLS 1, 2 Wood dryer 11 Drying furnace 12 Boiler 13 Exhaust pipe 14,15 Air layer 16 Piping 21 Mesh sheet 22 Wood flour layer 31 Mesh sheet 32 Wood chip layer 33 Wood chip 34 Air layer 100 Wood

Claims (8)

A drying furnace;
A hot air supply unit for supplying hot air into the drying furnace,
In the drying furnace, a wood powder layer is provided so as to cover the entire surface of the wood to be dried,
The said hot air supply part is a wood drying apparatus comprised so that a hot air may be supplied in the said drying furnace so that a hot air may pass in the said wood powder layer from the downward direction upwards. In the drying furnace, a wood chip layer is provided under the wood powder layer, and a plurality of wood chips are arranged,
The wood according to claim 1, wherein the hot air supply unit is configured to supply hot air into the drying furnace so that the hot air passes through the wood chip layer and the wood flour layer from below to above. Drying equipment. The wood chip layer is formed by arranging the wood chips on a mesh material that allows air to pass without passing wood chips,
The hot air supply unit is configured to supply hot air into the drying furnace so that the hot air passes through the mesh material, the wood chip layer, and the wood powder layer from below to above. The wood drying apparatus described in 1.   The wood drying apparatus according to any one of claims 1 to 3, wherein talc is contained in the wood powder layer. Place the wood to be dried in the wood powder layer provided in the drying furnace and cover the entire surface of the wood with wood powder,
A wood drying method for drying the wood by generating hot air and passing the wood powder layer from below to above. In the drying furnace, a wood chip layer is provided under the wood powder layer, and a plurality of wood chips are arranged,
The wood drying method according to claim 5, wherein the wood is dried by generating hot air and passing the wood chip layer and the wood powder layer from below to above. The wood chip layer is formed by arranging the wood chips on a mesh material that allows air to pass without passing wood chips,
The wood drying apparatus according to claim 6, wherein the wood is dried by generating hot air and passing the mesh material, the wood chip layer, and the wood powder layer upward from below.   The wood drying method according to any one of claims 5 to 7, wherein talc is contained in the wood powder layer.

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