Method for producing bamboo fuel

Abstract

To provide a method for producing bamboo fuel capable of fueling a bamboo material without chipping the bamboo material when extracting potassium and chlorine from the bamboo material.SOLUTION: In a raw bamboo bundle 10, each node 2 and a cavity 3 inside a bamboo culm are broken, so that all cavity water is eliminated and moisture inside can be discharged from a split cross section and an inner arc surface of the raw bamboo bundle. Therefore, free water in bamboo fibers becomes highly permeable, easily moving inside and outside the raw bamboo bundle 10, and potassium and chlorine are easily leached out externally through water that has permeated into the bamboo fibers. Thus, the contents of potassium and chlorine can be easily reduced merely by leaving the raw bamboo bundle 10 in an immersed state in water 22 without chipping a bamboo. Furthermore, since the raw bamboo bundle can discharge moisture also from the split cross section and the inner arc surface, it is in an easily dried state and is suitable as bamboo fuel 50.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for producing bamboo fuel from raw bamboo material. [Background technology]

[0002] In recent years, methods have been proposed for producing fuel using bamboo, such as the invention described in Patent Document 1. However, because bamboo is a grass plant, it contains potassium and chlorine, and there has been a problem in that this potassium (including ionic and ionic compounds) and chlorine (including ionic and ionic compounds) become factors that inhibit the combustion of bamboo (hereinafter referred to as "combustion inhibiting factors").

[0003] The reason why potassium inhibits combustion is that it turns into clinker and sticks to the heat-resistant material in the fuel combustion chamber, causing damage to the heat-resistant material and inhibiting the continuous combustion of the bamboo.The reason why chlorine inhibits combustion is that chlorine corrodes the fire-resistant material and heat transfer tubes in the combustion chamber, and if it is contained in the exhaust gas from the combustion chamber, it deteriorates the exhaust equipment.

[0004] Therefore, when bamboo fuel is put to practical use, it is necessary to remove the potassium and chlorine contained within the bamboo fuel, thereby reducing the potassium and chlorine content of the bamboo fuel to below a value (limit value) at which these potassium and chlorine do not become combustion inhibitors.

[0005] In Patent Document 1, bamboo material is crushed into fine particle chips, and then these bamboo chips (hereinafter referred to as "bamboo chips") are submerged in water to leach potassium and chlorine from within. Because the bamboo chips are in the form of fine particles, water can easily penetrate into the interior, and the potassium and chlorine dissolved in the water can easily be leached from within the chips. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2018-21134 Summary of the Invention [Problem to be solved by the invention]

[0007] However, while bamboo fuel in the form of bamboo chips, as in Patent Document 1 mentioned above, makes it easier to extract potassium and chlorine from the bamboo chips, it can also cause various problems, as described below, which has resulted in the practical application of bamboo fuel not progressing smoothly.

[0008] For example, a method for producing fuel from bamboo chips requires two steps: washing the bamboo chips in water and removing them from the water and drying them.However, such bamboo chips have a larger volume per weight than bamboo culms, and this increase in volume poses the problem of a significant increase in the amount of energy consumed in each step.

[0009] Specifically, in the process of producing fuel after bamboo chips are made, when the bamboo chips are washed in water, separate equipment is required to forcibly stir the bamboo chips in water and the energy required to operate it is required.In addition, because the bamboo chips are not in a state suitable for natural drying, a forced drying process is required, which poses the problem of separate equipment and energy required to operate the drying process.

[0010] For example, when bamboo chips are agitated in a drying drum in order to dry them in a short time, there is the problem that a drying facility with an agitation function and the energy required to operate it are required separately. On the other hand, when bamboo chips are spread out to a predetermined thickness and dried, the drying state of the upper and lower layers of the spread bamboo chips differs, so there is the problem that power energy is required to turn the bamboo chips upside down to switch the upper and lower layers.

[0011] In this way, producing bamboo fuel using bamboo chips requires special equipment, and additional energy is also required to operate the special equipment, making the energy efficiency of producing bamboo fuel extremely poor.As a result, the economic cost of producing bamboo fuel is far greater than the economic cost contribution of using it as fuel, which is a major obstacle to the practical use of bamboo fuel using bamboo chips.

[0012] Furthermore, since chipping bamboo increases the volume per unit weight of the bamboo, there is a problem in that a large amount of land is required to spread the bamboo chips in a designated area and dry them.

[0013] Furthermore, if the bamboo chips made from crushed bamboo are washed in water as they are, the bamboo chip debris will settle in the water storage facility or float in the water, which necessitates the need for equipment to prevent this, which creates the problem of making the washing in water cumbersome.

[0014] The present invention has been made to solve the above-mentioned problems, and aims to provide a bamboo fuel production method that can turn bamboo into fuel without the need to chip the bamboo to remove potassium and chlorine from it. [Means for solving the problem]

[0015] To achieve this objective, the bamboo fuel production method of the first invention comprises a bamboo splitting process in which raw bamboo culms produced from raw bamboo are split into long strips to produce a plurality of raw bamboo strips; a soaking process in which the plurality of raw bamboo strips produced by the bamboo splitting process are soaked in water for a predetermined period of time to dissolve potassium and chlorine from each raw bamboo strip into the water and produce a plurality of soaked raw bamboo strips in which the potassium and chlorine content of each raw bamboo strip is reduced to below a predetermined standard value; a drying process in which, after the soaking process, the plurality of soaked bamboo strips are lined up in a vertical or inclined position and naturally or forcedly dried to produce a plurality of dried bamboo strips; and a shape adjustment process in which, after the drying process, the dried bamboo strips, while still in their dried state, are crushed into chips or cut to a predetermined length to be processed and adjusted into dried bamboo chips or dried short bamboo strips, which are obtained as bamboo fuel.

[0016] According to the bamboo fuel production method of the first invention, raw bamboo culms produced from raw bamboo are split lengthwise into long strips in the bamboo splitting process (see Figure 2), producing multiple raw bamboo strips. The multiple raw bamboo strips produced in this bamboo splitting process are then immersed in water in a soaking process, where they are maintained in a soaked state (hereinafter also referred to as the "soaked state").

[0017] When the raw bamboo sachets are in this immersed state, the potassium and chlorine contained therein are dissolved into the water outside through the moisture within the raw bamboo sachets, and this elution reduces the potassium and chlorine content contained in each raw bamboo sachets.After a predetermined period of time has passed since the start of immersion of the raw bamboo sachets, when the potassium and chlorine content within the raw bamboo sachets has decreased to below a predetermined standard value, each raw bamboo sachets becomes an immersed bamboo sachets, and the production of multiple immersed bamboo sachets is completed.

[0018] According to this soaking process, the potassium and chlorine contained inside the raw bamboo can be reduced simply by soaking the bamboo in water and leaving it there, so there is no need to use chemicals to remove the potassium and chlorine.

[0019] The above-mentioned specified standard values for the potassium and chlorine content refer to the limit values at which potassium and chlorine become combustion inhibiting factors, as described in the "Background Art" section above. If the potassium and chlorine content is below the specified standard value, it means that there is no risk of potassium and chlorine becoming combustion inhibiting factors when the bamboo is burned, and if the potassium and chlorine content is above the specified standard value, it means that there is a risk of potassium and chlorine becoming combustion inhibiting factors when the bamboo is burned.

[0020] Here, the raw bamboo culm has been split, destroying the multiple nodes on the raw bamboo culm, and the hollow spaces between the nodes of the raw bamboo culm have also been destroyed, and the water that was in these hollow spaces (hereinafter referred to as "hollow water") has been expelled, making the raw bamboo culm more susceptible to drying than when it is left in its original state (see Figures 2(c) and 2(d)).

[0021] Furthermore, the cut surfaces on both sides of the width of the raw bamboo culm (the cross sections created by splitting the bamboo culm, corresponding to the cut surfaces 11 in Figures 2(c) and 2(d)) and the surface that was originally the inner surface of the hollow part of the raw bamboo culm (hereinafter referred to as the "inner arc surface", corresponding to the inner arc surface 12 in Figures 2(c) and 2(d)) are exposed to the outside, and moisture can be discharged from these cut surfaces and inner arc surfaces, so the raw bamboo culm is more permeable to water and dries more easily than in its raw state.

[0022] As a result, when raw bamboo sachets are submerged in water during the soaking process, the free water in the bamboo fibers of the raw bamboo sachets becomes highly permeable, allowing it to easily move between the inside and outside.For example, by soaking the bamboo sachets submerged in water for a period of approximately one week to one month, potassium and chlorine will dissolve into the water through the water that has penetrated the bamboo fibers and will be expelled from the bamboo sachets until the potassium and chlorine content falls below the specified standard value, and as a result, the raw bamboo sachets become soaked bamboo sachets.

[0023] Bamboo sachets that have undergone this soaking process and whose potassium and chlorine contents have fallen below the prescribed standard values are called soaked bamboo sachets. Multiple soaked bamboo sachets are lined up vertically or at an angle and then dried naturally or forcedly in the drying process. Adjacent soaked bamboo sachets are arranged so that they do not overlap or touch each other, so that they do not interfere with each other's drying.

[0024] Here, natural drying refers to removing moisture from an object through natural phenomena or environments such as sunlight, a decrease in atmospheric humidity, or wind, thereby reducing the moisture content of the object and bringing the object to a dry state, and includes what is called natural drying.

[0025] Forced drying refers to the process of removing moisture from an object and lowering its moisture content through artificial phenomena or environments, such as using equipment (including heat sources) that forcibly generate infrared rays, hot air, temperature rise, or other moisture-evaporating phenomena in place of or in addition to natural phenomena, thereby forcibly increasing the temperature or decreasing the humidity in the space, and this includes what is called artificial drying.

[0026] In this drying process, multiple soaked bamboo packs are dried using natural drying or forced drying.As mentioned above, bamboo becomes easier to dry when processed into packs, which provides more advantageous effects and results than conventional methods of drying bamboo chips to produce bamboo fuel.

[0027] For example, in the drying process of bamboo chips, the bamboo chips are agitated in a drying drum to prevent uneven drying of the bamboo chips, but when drying soaked bamboo sachets, such drying equipment with agitation functions and the energy required to operate it are not necessary, making the drying process significantly simpler and more streamlined.

[0028] Furthermore, with soaked bamboo packs, when the bamboo chips are laid out to a specified thickness and dried, the upper and lower layers of the bamboo chips dry in different states, so there is no need to turn them over to swap the top and bottom.This means that if the turning is done mechanically, the equipment and power energy required are not required, and if the turning is done manually, the effort and hassle involved can be avoided, further reducing labor costs.

[0029] In addition, this drying process can be carried out using either natural or forced drying, but natural drying in particular offers more effective benefits than drying bamboo that has been cut into chips. To give a specific example, natural drying, compared to forced drying, eliminates the need for a heat source and the energy required for its operation, thereby reducing the energy consumed in producing bamboo fuel.

[0030] Furthermore, when natural drying is performed, the bamboo stalks are arranged vertically or at an angle, so the moisture inside the stalks is subjected to the action of gravity and flows down through the vascular bundles inside. In addition to evaporation from the outer arc surfaces of the stalks, evaporation also occurs from the cut surfaces and inner arc surfaces of the stalks. Therefore, compared to natural drying of raw bamboo culms, there is no cavity water and the surface area in contact with the outside air is increased, which further promotes natural drying.

[0031] Furthermore, since the soaked bamboo sachets are lined up and propped up for natural or forced drying, there is no need to lay them out in layers of a specified thickness, like bamboo chips, overlapping each other. This prevents the occurrence of uneven drying that would occur if the bamboo were dried in such an overlapping state, i.e., damp areas due to insufficient drying in the overlapping areas, and prevents uneven drying of the bamboo as a whole during drying.

[0032] Furthermore, raw bamboo sacks have a smaller volume per unit mass than bamboo chips, which reduces the amount of energy required in each process. For example, in the soaking process, potassium and chlorine are dissolved and removed by simply leaving the bamboo sacks in water, eliminating the need for equipment to forcefully agitate the bamboo chips in water and the energy required to operate it, as is the case with conventional underwater washing of bamboo chips.

[0033] In this way, because the soaking and drying processes are carried out while the bamboo is still in its sack form, the special equipment required for bamboo chips, as well as the extra energy required to operate that equipment, are not required.As a result, the energy efficiency required for producing bamboo fuel can be improved, and the economic cost of producing bamboo fuel is smaller than the economic cost contribution of using bamboo fuel, making a significant contribution to the practical use of bamboo fuel.

[0034] Moreover, unlike bamboo chips, there is no need to spread them out in a predetermined place for natural drying, and the soaked bamboo booklets can be propped up and dried naturally or forcedly, so the space required for drying can be reduced and drying can be carried out even in a small space.

[0035] Furthermore, raw bamboo sachets do not contain large amounts of fine bamboo debris generated by crushing, as do bamboo chips, so such bamboo debris does not settle to the bottom of the water or float in the water or on the surface during the soaking process, eliminating the need for equipment to remove them and making it easy to remove potassium and chlorine from the water.

[0036] Here, sun drying refers to a natural drying method in which an object is dried in a sunny environment where sunlight is irradiated onto the object, and can be done either outdoors or indoors as long as it is in the sun. Shade drying refers to a natural drying method in which an object is dried in a shady environment where sunlight is not irradiated onto the object, and can be done either outdoors or indoors as long as it is in the shade.

[0037] The dried bamboo sachets produced from the soaked bamboo sachets after this drying process are then shaped in a shaping process to produce bamboo fuel. In this shaping process, the dried bamboo sachets in a dry state are crushed into chips and processed into dried bamboo chips, which can be used as bamboo fuel, or the dried bamboo sachets in a dry state can be cut to a predetermined length and processed into dried short bamboo sachets, which can be used as bamboo fuel.

[0038] Dried bamboo strips are long strips that are cut so that their length is the same as or slightly shorter than that of natural, fresh bamboo. As a result, they are too long and difficult to handle when put into a combustion chamber and burned as fuel. Therefore, they are reprocessed into chips or strips to make them easier to handle and put into a combustion chamber as fuel.

[0039] This shape adjustment process allows the bamboo to be processed and adjusted into a form that is easy to handle when burned as bamboo fuel, while by having this shape adjustment process as the final process, the bamboo remains in the form of long bamboo sheets that are convenient for soaking and drying in the soaking and drying processes that precede it, making it possible to convert bamboo into fuel through a simpler and more energy-efficient processing process.

[0040] The bamboo fuel production method of the second invention is the bamboo fuel production method of the first invention, in which the drying process is natural drying in which multiple soaked bamboo sachets are left lined up in a vertical or inclined position, and is natural drying by drying in the sun or shade.

[0041] This bamboo fuel production method of the second invention achieves the same functions and effects as the bamboo fuel production method of the first invention, and since the soaked bamboo stalks are dried naturally by drying in the sun or shade, there is no need to waste heat energy or power energy in drying the bamboo stalks, which reduces the energy consumption required to produce bamboo fuel and improves the production efficiency of bamboo fuel.

[0042] The bamboo fuel production method of the third invention is the bamboo fuel production method of the first or second invention, and includes a soaking water recycling process in which the soaking water in which the raw bamboo stalks are soaked in the soaking process is recovered and reused as fertilizer for rice paddies or as a raw material for fertilizer for rice paddies.

[0043] This bamboo fuel production method of the third invention achieves the same functions and effects as the bamboo fuel production method of the first or second invention, and since the potassium dissolved from the raw bamboo stalks during the soaking process is contained in the soaking water, this soaking water can be used as fertilizer for rice paddies or reused as a raw material for rice paddy fertilizer, and by supplying this rice paddy fertilizer to rice cultivation areas such as paddy fields, potassium can be replenished in the rice cultivation areas and utilized in the growth of rice. [Effects of the Invention]

[0044] According to the present invention, when the potassium and chlorine content of raw bamboo is reduced or removed, bamboo fuel can be produced from the raw bamboo without chipping the bamboo, thereby eliminating various problems that arise when chipping the raw bamboo before removing the potassium and chlorine from it, and promoting the use of bamboo fuel. [Brief explanation of the drawings]

[0045] [Figure 1] 1 is a flowchart illustrating a bamboo fuel production method according to a first embodiment of the present invention. [Figure 2] (a) is a front view of a raw bamboo culm 1, (b) is a plan view (top view) of the raw bamboo culm 1, (c) is a front view of a raw bamboo booklet 10 created by vertically splitting one raw bamboo culm 1 into four equal parts, and (d) is a side view of the raw bamboo booklet 10 of (a). [Figure 3] (a) is a front view of the raw bamboo pack 10, (b) is a side view of the raw bamboo pack 10, (c) is a back view of the raw bamboo pack 10, and (d) is a plan view (top view) of the raw bamboo pack 10. [Figure 4]FIG. 10 is a diagram showing the state of the raw bamboo packs 10 immersed in the immersion process S3, and is a diagram showing the internal structure of the water tank 21 in which a plurality of raw bamboo packs 10 are immersed together. [Figure 5] These figures show the drying state of the soaked bamboo books 20 in the drying process S4, where (a) is a front view showing multiple soaked bamboo books 20 leaning against a propping stand 31, and (b) is a side view of (a) showing the drying state of the soaked bamboo books 20 leaning upright against the propping stand 31. [Figure 6] 10 is a flowchart of a bamboo fuel production method according to a second embodiment. [Figure 7] 10 is a flowchart of a bamboo fuel production method according to a third embodiment. [Figure 8] 10 is a flowchart illustrating a bamboo fuel production method according to a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0046] Hereinafter, a bamboo fuel production method according to one embodiment of the present invention will be described with reference to the accompanying drawings.

[0047] Fig. 1 is a flowchart of a bamboo fuel production method according to a first embodiment of the present invention. Fig. 2(a) is a front view of a raw bamboo culm 1, Fig. 2(b) is a plan view (top view) of the raw bamboo culm 1, Fig. 2(c) is a front view of a raw bamboo booklet 10 produced by vertically splitting one raw bamboo culm 1 into four equal parts, and Fig. 2(d) is a side view of the raw bamboo booklet 10 of Fig. 2(a).

[0048] Figure 3(a) is a front view of the raw bamboo booklet 10, Figure 3(b) is a side view of the raw bamboo booklet 10, Figure 3(c) is a back view of the raw bamboo booklet 10, and Figure 3(d) is a plan view (top view) of the raw bamboo booklet 10.

[0049] Fig. 4 shows the state of the raw bamboo books 10 soaked in the soaking process S3, and is a diagram of the internal structure of the water tank 21 in which multiple raw bamboo books 10 are soaked together. Fig. 5 shows the drying state of the soaked bamboo books 20 in the drying process S4, with Fig. 5(a) being a front view showing multiple soaked bamboo books 20 leaning against the stand 31, and Fig. 5(b) being a side view of Fig. 5(a) showing the drying state of the soaked bamboo books 20 leaning against the stand 31 in a vertical position.

[0050] As shown in Figure 1, the bamboo fuel production method includes a bamboo pretreatment process S1, a bamboo splitting process S2, a soaking process S3, a drying process S4, and a shape adjustment process S5, and further includes an additional process of reusing the soaking water S6.

[0051] <Bamboo pre-treatment process S1> The bamboo pre-treatment process S1 is a process for processing raw bamboo 01 that has been felled from a bamboo growing area, as shown in Figure 1, and involves removing branches and leaves from this raw bamboo 01 by cutting or the like to produce raw bamboo culm 1, which is the culm of the raw bamboo 01 (see Figures 2(a) and 2(b)).

[0052] Here, raw bamboo 01 is also called green bamboo, and refers to long, freshly cut bamboo harvested from a bamboo forest, which is in its natural state without any processing such as heat or dyeing.

[0053] Furthermore, a live bamboo culm 1 is a long culm produced by removing the branches and leaves from live bamboo, and has multiple nodes 2, 2, ... spaced apart along its length (the vertical direction in Figure 2(a)), with a hollow section 3 inside between each node 2, and refers to the part that corresponds to the trunk of a tree.

[0054] Here, as shown in Figures 2(a) and 2(b), raw bamboo culm 1 is produced from raw bamboo 01 and has the property of releasing moisture in a dry environment and absorbing moisture in a humid environment, and the inside of this raw bamboo culm 1 contains free water and bound water.

[0055] Inside the raw bamboo culm 1, free water is the water that exists in the cell cavities and spaces between the cell walls, and bound water is the water that is within the cell walls and is chemically bonded to the bamboo fiber molecules.When this bound water decreases, the cell walls become thinner, and the raw bamboo culm 1, which is an assembly of these cell walls, shrinks.The cell cavities inside it, which allow the free water to enter, also shrink, resulting in a decrease in the water permeability and water absorption of the raw bamboo culm 1.

[0056] Therefore, when the raw bamboo culm 1 becomes dry and its moisture content drops below the fiber saturation point, the bamboo culm in this dry state (hereinafter referred to as "dried bamboo culm") has reduced water absorption and drainage properties (hereinafter referred to as "water permeability"), so even if such dried bamboo culm is immersed, it becomes difficult to dissolve the potassium and chlorine contained within it into water, and it becomes difficult to reduce the potassium and chlorine content (including concentration) within it to below the above-mentioned specified standard value.

[0057] For this reason, in the bamboo fuel production method of the present invention (embodiment), a soaking process S3 and a drying process S4 for producing bamboo fuel 50 are carried out on raw bamboo culms 10 produced from raw bamboo culms 1 processed from raw bamboo 01 that still retains water permeability, as shown in Figure 1, rather than dried bamboo culms that have lost their water permeability.

[0058] Here, a raw bamboo booklet 10 is a long book-like body produced by splitting a raw bamboo culm 1 along its axial direction, and is produced by splitting the raw bamboo culm 1 into N pieces (N is a natural number greater than or equal to 2).

[0059] <Bamboo splitting process S2> As shown in Figure 1, the bamboo splitting process S2 is a process for processing the raw bamboo culms 1 produced in the bamboo pre-treatment process S1, and involves splitting them using a bamboo splitter or bamboo splitting machine to produce long, book-shaped raw bamboo books 10. Note that a bamboo splitter is a manual tool that splits bamboo manually, while a bamboo splitting machine is a mechanical device that splits bamboo using mechanical driving force.

[0060] As shown in Figures 2(a) and 2(b), the raw bamboo booklet 10 is a long booklet of the same or similar length as the raw bamboo 01, for example, about 2 m or longer, generally about 2 to 4 m in length.

[0061] As shown in Figures 2(c) and 2(d), this raw bamboo booklet 10 is made by splitting the raw bamboo culm 1 shown in Figures 2(a) and 2(b). For example, the raw bamboo booklet 10 is made by splitting the raw bamboo culm 1 (see Figure 2(b)) in a plan view into N pieces (N is a natural number of 2 or more; the same applies below) in the circumferential direction of the raw bamboo culm 1 by making splits in the axial direction of the raw bamboo culm 1 (the vertical direction in Figure 2(a)) using a bamboo splitter or the blade of a bamboo splitting machine, so as to divide it into N pieces (including equal divisions) in the circumferential direction of the raw bamboo culm 1, and the raw bamboo booklet 10 is made of N pieces of booklet-shaped bodies obtained from one raw bamboo culm 1.

[0062] In this embodiment, as shown in Fig. 2(c) and Fig. 2(d), the raw bamboo pack 10 is exemplified as being obtained by dividing the raw bamboo culm 1 into four equal parts (N=4).

[0063] As shown in Figures 2(c) and 2(d), according to a raw bamboo booklet 10 made by splitting a raw bamboo culm 1 vertically, the multiple nodes 2, 2, ... that were present in the raw bamboo culm 1 are destroyed by splitting the raw bamboo culm 1 vertically, and therefore the hollow portion 3, which is the internal space that exists between adjacent nodes 2, 2 in the axial direction of the raw bamboo culm 1, is destroyed, and the cavity water that was present in this hollow portion 3 can be discharged outside the raw bamboo culm 1.

[0064] This raw bamboo booklet 10 has been split by splitting the raw bamboo culm 1, which has split surfaces 11, 11 on both sides of its width, exposing the inner arc surface 12 that was the inner surface 4 of the hollow portion 3 of the raw bamboo culm 1 (see Figures 2(a) and 2(b)), and also exposing the outer arc surface 13 that was the outer surface 5 of the raw bamboo culm 1 (see Figures 2(a) and 2(b)).

[0065] Therefore, with the raw bamboo booklet 10, the cavity water within the raw bamboo culm 1 does not remain sealed, and all of this cavity water is expelled. In addition, the moisture within the raw bamboo booklet 10 can be discharged from the cut surfaces 11, 11, inner arc surface 12, and outer arc surface 13 of the raw bamboo booklet 10, so the raw bamboo culm 1 has higher water permeability and is easier to dry than in its original state.

[0066] <Soaking process S3> As shown in Figure 1, the soaking process S3 is a process for processing the raw bamboo books 10 produced in the bamboo splitting process S2. A plurality of the raw bamboo books 10 are immersed in water together, and the immersion state is maintained for a predetermined period of time from the start of immersion to produce soaked bamboo books 20 from the raw bamboo books 10.

[0067] In this soaking process S3, the soaking period measurement process S301 measures the time that has elapsed since the start of soaking the raw bamboo booklet 10, and when this elapsed time reaches a predetermined period, it is deemed that the potassium and chlorine content in the raw bamboo booklet 10 has decreased to a value below the predetermined standard value, and the production of the soaked bamboo booklet 20 has been completed, and the soaking process S3 ends.

[0068] Here, the relationship between the time elapsed since the start of soaking the raw bamboo packs 10 and the amount of potassium and chlorine eluted from the soaked raw bamboo packs 10 has been measured and understood in advance through prior experiments, etc., and based on this relationship between the two, in the soaking process S3, when the timing result of the soaking period measurement process S301 has passed a predetermined period, i.e., when the raw bamboo packs 10 have been soaked from the start of soaking until the predetermined period has passed, the potassium and chlorine content in the raw bamboo packs 10 is treated as having decreased to a value below the above-mentioned predetermined standard value.

[0069] For example, in the soaking process S3, the raw bamboo booklet 10 is soaked for a period of about one week to one month, so that potassium and chlorine are dissolved into the water 22 that has penetrated into the bamboo fibers of the raw bamboo booklet 10, and are discharged outside the raw bamboo booklet 10 until the potassium and chlorine content falls below the specified standard value, and as a result, the raw bamboo booklet 10 becomes a soaked bamboo booklet 20.

[0070] In particular, with regard to the raw bamboo pack 10, by processing the raw bamboo culm 1 into a split form, as described above, the free water in the bamboo fibers can easily move between the inside and outside of the raw bamboo pack 10, making it highly permeable.Therefore, the potassium and chlorine contained inside the raw bamboo pack 10 can easily be eluted to the outside through the water that has penetrated into the bamboo fibers.Therefore, the potassium and chlorine content can be reduced by simply leaving the raw bamboo pack 10 immersed in water 22 without chipping the bamboo.

[0071] As shown in Figure 4, in the immersion process S3, multiple raw bamboo packs 10 are immersed in water 22 stored in a water tank 21. This water tank 21 is a container with enough capacity to simultaneously immerse multiple raw bamboo packs 10. In addition, in the immersion process S3, the multiple raw bamboo packs 10 are completely submerged in the water 22 to facilitate the elution of potassium and chlorine from the inside of the multiple raw bamboo packs 10 into the water 22.

[0072] For this reason, in the immersion process S3, a mesh pallet 23 is used to hold all the raw bamboo books 10 put into the water tank 21 in the water 22, in order to prevent the multiple raw bamboo books 10 from floating to the surface of the water 22 and to ensure that each and every raw bamboo book 10 comes into contact with the water in its entirety.

[0073] This mesh pallet 23 is a rectangular basket-like body with six sides covered with a mesh body 23a. This mesh pallet 23 can store multiple raw bamboo packs 10 inside, and water can flow inside and outside through the mesh of the mesh body 23a that covers each side of the inside, so multiple raw bamboo packs 10 can be immersed in the water 22 in a submerged state in one place without being scattered and scattered into the water 22.

[0074] With this mesh pallet 23, for example, a portion of the mesh pallet 23 can be opened while it is installed on the ground, and after storing multiple raw bamboo packs 10 inside the mesh pallet 23, the open portion can be closed and the mesh pallet 23 can be lowered below the water surface of the water tank 21, causing the entire mesh pallet 23 to sink into the water 22, and as a result, all of the raw bamboo packs 10 inside the mesh pallet 23 will be immersed in the water 22 in a completely submerged state.

[0075] Furthermore, even if the raw bamboo packs 10 are subjected to buoyancy and rise up inside the mesh pallet 23, the raw bamboo packs 10 are held down by the net-like body 23a covering the ceiling surface of the mesh pallet 23 and are prevented from rising up.

[0076] The mesh pallet 23 is lifted up or down using a crane (not shown) via a hanging wire 24 passed through an eyebolt 23b provided on its top surface, and is moved in and out of the water tank 21.

[0077] In this way, the raw bamboo packs 10 are soaked in water 22. After a predetermined period of time has passed since the start of soaking, and the potassium and chlorine are diluted to a level below the above-mentioned predetermined standard value, which is a content that does not inhibit the combustion of the bamboo fuel 50, it is determined that the potassium and chlorine have been sufficiently removed, and the raw bamboo packs 10 are taken out of the water 22 as a plurality of soaked bamboo packs 20.

[0078] <Drying process S4> As shown in Figure 1, the drying process S4 is a process for further processing the soaked bamboo booklets 20 whose potassium and chlorine contents have been reduced to below the predetermined standard values by the soaking process S3, and the soaked bamboo booklets 20 are dried to produce dried bamboo booklets 30.

[0079] According to this drying process S4, the soaked bamboo books 20 taken out of the water tank 21 after the soaking process S3 are naturally dried, and the water is removed from the soaked bamboo books 20 by flowing out or evaporating, so that the moisture is removed from the soaked bamboo books 20, and the soaked bamboo books 20 become dried and turn into dried bamboo books 30.

[0080] As shown in Figure 5(a), in the drying process S4, adjacent soaked bamboo books 20 are arranged with a horizontal gap between them, but not overlapping or touching each other, so that adjacent soaked bamboo books 20 do not interfere with each other's drying. Also, as shown in Figure 5(b), each of the multiple soaked bamboo books 20 is placed in a vertical position, and then naturally dried in this state to produce dried bamboo books 30.

[0081] The natural drying used in this drying process S4 can be either sun drying or shade drying. In the case of sun drying, multiple soaked bamboo sachets 20 are lined up vertically in a location outdoors or indoors where they are exposed to direct or indirect sunlight (sunlight), and then the multiple soaked bamboo sachets 20 are dried by exposing them to sunlight. In the case of shade drying, multiple soaked bamboo sachets 20 are lined up vertically in a shady location indoors or outdoors where they are not exposed to sunlight, such as under the eaves or in a covered plaza, and then the multiple soaked bamboo sachets 20 are dried without being exposed to sunlight.

[0082] Here, if the soaked bamboo booklets 20 are dried naturally in the shade under the eaves, even in areas with a humid climate compared to the Pacific coast, such as the Sea of Japan coast, the moisture contained in the soaked bamboo booklets 20 can be removed by leaving them for about a week, making them sufficiently dry for use as fuel.

[0083] In addition, a drying location that is indoors and exposed to sunlight refers to, for example, a drying location that is indoors but has windows, walls, or a ceiling made of glass or other materials that allow sunlight to pass through into the room.

[0084] In this way, if the wet soaked bamboo fence 20 is left to dry in the sun for a few days or in the shade for about a week, the soaked bamboo booklet 20 will become a sufficiently dried, dried bamboo booklet 30.This high dryness is due to the fact that the soaked bamboo booklet 20 is a form with good water permeability, obtained by splitting the raw bamboo culm 1.

[0085] Specifically, by splitting the bamboo into booklets 10, 20, 30, the multiple nodes 2, 2, ... that were present in the raw bamboo culm 1 are destroyed, allowing the moisture in each hollow portion 3 within the raw bamboo culm 1 that was blocked by each node 2 to be eliminated.In addition to the outer arc surfaces 13 of the bamboo culms 10, 20, 30, their split surfaces 11 and inner arc surfaces 12 can also be exposed to the outside air, making it easier to expel moisture from the bamboo fibers through these split surfaces 11, 11, inner arc surfaces 12, and outer arc surfaces, making it easier to dry than if the raw bamboo culm 1 were left to dry naturally.

[0086] In other words, by using bamboo in book form such as the bamboo booklets 10, 20, and 30, the drying time for the same mass of bamboo can be shortened, and the overall production period for bamboo fuel 50 can be shortened.

[0087] Furthermore, in this drying process S4, the multiple soaked bamboo books 20 are dried in a vertical position, i.e., with one longitudinal end of each soaked bamboo book 20 positioned higher than the other end, and leaned against the leaning stand 31. This makes it easier for the moisture remaining in each soaked bamboo book 20 to flow downward through the vascular bundles, further improving the drying efficiency of the soaked bamboo books 20.

[0088] In particular, as shown in Figure 5, drying the soaked bamboo books 20 in a vertical position helps to allow the moisture remaining in the vascular bundles inside the soaked bamboo books 20 to flow naturally and be discharged more easily than when drying the soaked bamboo books 20 in an inclined or horizontal position, which results in the drying time of the soaked bamboo books 20 being shortened and the drying efficiency being improved.

[0089] Incidentally, if the length of the submerged bamboo books 20 is about 2 m, it is easy to line up the submerged bamboo books 20 in a vertical position, but if the length of the submerged bamboo books 20 is significantly longer than 2 m, at about 3 to 4 m, it becomes difficult to line up the submerged bamboo books 20 in a vertical position, so in such cases it is possible to line up the submerged bamboo books 20 in an inclined position rather than in a vertical position.

[0090] When the soaked bamboo books 20 are dried in an inclined position in this way, the angle of inclination of the soaked bamboo books 20 is gentler than when the soaked bamboo books 20 are dried in a vertical position, so the function of allowing the moisture remaining in the vascular bundles inside the soaked bamboo books 20 to flow naturally downward and be discharged is reduced. However, compared to drying in a horizontal position, this still contributes to allowing the moisture remaining in the vascular bundles inside the soaked bamboo books 20 to flow naturally downward and be discharged, so as a result, the drying time of the soaked bamboo books 20 can be shortened and the drying efficiency can be improved.

[0091] In this embodiment, "vertical position" refers to a vertical position relative to the ground or a position close to this, for example, a position in which the immersed bamboo book 20 is tilted at an angle of approximately 70° to 90° relative to the ground. Furthermore, "inclined position" refers to a position inclined relative to the ground excluding the vertical position and the horizontal position, for example, a position in which the immersed bamboo book 20 is tilted at an angle of approximately 20° to 70° relative to the ground. Furthermore, "horizontal position" refers to a horizontal position relative to the ground or a position close to this, for example, a position in which the immersed bamboo book 20 is tilted at an angle of approximately less than 20° relative to the ground.

[0092] Furthermore, as described above, the multiple immersed bamboo books 20 are long bamboo books (hereinafter referred to as "long bamboo books") that are approximately 2 m or longer in length, and compared to short bamboo books (hereinafter referred to as "short bamboo books") that are approximately 1 m or shorter in length, they have the following technical significance.

[0093] First, when the immersed bamboo booklet 20 is a short bamboo booklet, its length is less than half that of a long bamboo booklet, and as a result, its mass is also less than half, making it more likely to tip over when placed in a vertical position.However, when the immersed bamboo booklet 20 is a long bamboo booklet, its mass is greater due to its length, making it less likely to tip over, especially when placed in a vertical position.

[0094] Furthermore, assuming that the soaked bamboo books 20 are lightweight, short books, if they are lined up vertically or at an angle and dried naturally in the sun or shade, there is a risk that they may be blown away or toppled over by light breezes (wind speed 1.6 to 5.4 m / s) or Japanese winds (wind speed 5.5 to 7.9 m / s), especially outdoors. In contrast, if the soaked bamboo books 20 are long, even if they are lined up vertically or at an angle, they can be prevented from being blown away or toppling over by light breezes or Japanese winds (except strong ones).

[0095] Furthermore, if the soaked bamboo books 20 are short, it is difficult to line them up outdoors and dry them naturally in a vertical position as described above. For example, they can be simply stacked in a disorderly manner and left to dry naturally. However, in such a case, the short bamboo books at the bottom of the stack will have poorer breathability than the short bamboo books above them, and will not dry well, so they will not be able to dry sufficiently by simply leaving them to dry naturally.

[0096] Therefore, in such cases, even if the bamboo is dried naturally, it will be necessary to turn the stacked short bamboo sachets upside down or to force-dry them using a heat source, which requires additional labor, effort, and energy to produce bamboo fuel 50, thereby increasing the production cost.

[0097] Forced drying refers to, for example, drying a drying chamber containing multiple soaked bamboo books 20 using infrared rays or hot air generated from a heat source, thereby reducing the humidity within the drying chamber and drying the soaked bamboo books 20.

[0098] Furthermore, if the soaked bamboo sachets 20 are short bamboo sachets, it is possible to bundle several of them together with binding material and allow them to dry naturally, or to use these bundled short bamboo sachets as fuel. However, in this case, the short bamboo sachets on the inside of the bundle will have poorer breathability than the short bamboo sachets on the outside, making them less dry, so in such a bundled form, simply leaving them to dry naturally will not allow them to dry sufficiently.

[0099] Therefore, in such cases, it becomes necessary to use forced thermal energy such as hot air to dry the bamboo, which requires additional labor, effort, and energy to produce the bamboo fuel 50, thereby increasing the production cost.

[0100] From the above, it can be said that it is more preferable to use the long bamboo sachets 20 in a vertical, tilted or horizontal position, especially when drying multiple soaked bamboo sachets 20 together by natural drying, and to dry them while ensuring breathability by leaving a certain distance between adjacent long bamboo sachets so that they do not come into contact with each other. In particular, it can be said that it is more preferable to place the long bamboo sachets vertically, leaning them against a wall in a vertical or tilted position, in order to quickly discharge the moisture remaining in the vascular bundles inside the soaked bamboo sachets 20.

[0101] <Form adjustment process S5> As shown in Figure 1, the shape adjustment process S5 is a process for processing the dried bamboo booklets 30 produced in the drying process S4, and adjusts the shape of the dried bamboo booklets 30 to make them easier to burn, thereby producing the final bamboo fuel 50.

[0102] In this shape adjustment process S5, the chipping process S501 involves using a crusher such as a chipper to process and adjust the dried bamboo booklets 40 into chip-like form, and producing dried bamboo chips 40 from the long bamboo booklets 30, which can then be obtained as bamboo fuel 50. The dried bamboo chips 40 produced in this shape adjustment process S5 have already had potassium and chlorine removed and have been dried, so there is no need to finely adjust the shape of the chips to make them suitable for these processes, and quality control such as size during chipping can be easily carried out.

[0103] Moreover, the dried bamboo chips 40 produced by this shape adjustment process S5 are in the chip-like form described above, which makes them easy to handle, such as being easily transported as bamboo fuel 50 and easily put into the combustion chamber. Furthermore, as described in the background art section, bamboo in chip form is not suitable for natural drying, and forced drying requires additional effort, labor, and energy consumption, but the dried bamboo chips 40 of this embodiment are naturally dried in the form of long bamboo sticks in the drying process S4 before being processed and adjusted into bamboo chips, so although they are in the form of bamboo chips, troublesome forced drying is not required, and bamboo fuel 50 in chip form can be easily produced.

[0104] <Immersion water reuse process S6> As shown in Figure 1, the soaking water reuse process S6 is a process in which the water 22 in which the raw bamboo packs 10 were soaked in the soaking process S3, which is an aqueous solution 60 containing potassium and chlorine eluted from the raw bamboo packs 10 (referred to as "soaking water"), is recovered from the water storage tank 21, and the recovered soaking water 60 is used to produce rice fertilizer 70 for use in rice cultivation.

[0105] In this steep water reuse step S6, the potassium and chlorine contents in the steep water 60 recovered from the water storage tank 21 are measured, and based on the measurement results, the steep water 60 is used as is as the paddy rice fertilizer 70, or the paddy rice fertilizer 70 is produced using the steep water 60 as a raw material. For example, if the chlorine contained in the steep water 60 is not necessary as a component of the paddy rice fertilizer 70, the chlorine is removed from the steep water 60 to produce the paddy rice fertilizer 70.

[0106] Bamboo is a grass plant like rice and therefore requires potassium. The soaking water 60 containing potassium eluted from the bamboo can be effectively reused as rice fertilizer 70, so there is no need to dispose of the soaking water 60 in nature, and no disposal facility is required.

[0107] <Using bamboo fuel production methods> Next, the process flow of the bamboo fuel production method of this embodiment configured as described above will be explained with reference to Figure 1. First, as shown in Figure 1, according to the bamboo fuel production method, branches and leaves are removed from long, felled raw bamboo 01 in the bamboo pre-processing step S1 to produce long raw bamboo culms 1. After this, the process moves to the bamboo splitting step S2.

[0108] In the bamboo splitting process S2, the long raw bamboo culms 1 are split vertically to produce multiple long raw bamboo volumes 10. The raw bamboo volumes 10 produced in this bamboo splitting process S2 are transferred to the water storage tank 21 for the next soaking process S3, where they are processed in the soaking process S3.

[0109] In the immersion process S3, a predetermined number of raw bamboo packs 10 are placed together in a mesh pallet 23, and while still inside this mesh pallet 23, the mesh pallet 23 is lowered into the water 22 below the surface of the water tank 21 by a crane (not shown) via a hanging wire 24, and is immersed completely submerged in this water 22. At this time, the predetermined number of raw bamboo packs 10 are kept completely submerged in the water 22 by the mesh pallet 23 so that they do not float to the surface of the water (see Figure 4).

[0110] After the raw bamboo packs 10 start to be immersed, they are kept immersed for a predetermined period (approximately one week to one month) based on the measurement (timekeeping) of the immersion period measurement process S301. As the immersion continues, the potassium and chlorine in each raw bamboo pack 10 are dissolved into the water 22 through the water that has penetrated into the bamboo fibers of each raw bamboo pack 10, and the potassium and chlorine contents in each raw bamboo pack 10 are diluted until they fall below the predetermined standard values.

[0111] Then, in the soaking process S3, when a predetermined period has elapsed since the start of measuring the soaking period by the soaking period measurement process S301, the predetermined number of raw bamboo volumes 10 are treated as having been diluted until the potassium and chlorine contents fall below predetermined standard values, and the raw bamboo volumes 10 are treated as having become soaked bamboo volumes 20.The production of the predetermined number of soaked bamboo volumes 20 is completed, and this soaking process S3 ends.

[0112] Then, when the soaking process S3 is finished and the production of the soaked bamboo books 20 is completed, a predetermined number of soaked bamboo books 20 are lifted out of the water 22 in the water tank 21 together with the mesh pallets 23 by a crane (not shown) via the hanging wires 24 and removed from the water tank 21. After this, the soaked bamboo books 20 are transported to the drying location for the next drying process S4 while still in the mesh pallets 23 for convenience in transportation, and are then removed from the mesh pallets 23 and processed in this drying process S4.

[0113] In the drying process S4, a predetermined number of soaked bamboo books 20 that have undergone the soaking process S3 are placed in a vertical position using a support device called a prop-up stand 31 (see Figure 5(b)), and adjacent soaked bamboo books 20 are arranged in a drying area with a gap between them horizontally and spaced apart so that they do not overlap but touch each other (see Figure 5(a)), and then left to dry naturally.

[0114] The soaked bamboo sacks 20 are left for a predetermined period of time in the drying process S4 until the water drains out or evaporates from them through natural drying. After that, once the water is removed from each soaked bamboo sack 20, each soaked bamboo sack 20 becomes dry, and the production of a predetermined number of dried bamboo sacks 30 is completed, and this drying process S4 ends.

[0115] After the drying step S4, the dried bamboo packs 30 are transferred to the next shape adjustment step S5 while maintaining their dry state. In this shape adjustment step S5, a predetermined number of dried bamboo packs 30 are processed and adjusted into chip-like form using a crusher such as a chipper, and these chip-like dried bamboo are produced as dried bamboo chips 40. These dried bamboo chips 40 are used as bamboo fuel 50, and this bamboo fuel production method is completed.

[0116] After the soaking step S3 is completed, a soaking water reuse step S6 is carried out separately from the drying step S4 and the shape adjusting step S5. In this soaking water reuse step S6, the soaking water 60 is collected from the water storage tank 21 used in the soaking step S3 and stored in a storage tank (not shown). This soaking water 60 can be used as is, or after the potassium and chlorine contents of the soaking water 60 have been appropriately readjusted, by supplying it to a rice cultivation field such as a paddy field as rice fertilizer 70.

[0117] <Modification of the bamboo fuel production method of the first embodiment> Next, with reference to Figs. 6 to 8, bamboo fuel production methods according to second to fourth embodiments, which are modifications of the first embodiment, will be described.

[0118] Figure 6 is a flowchart for the bamboo fuel production method of the second embodiment, and Figure 7 is a flowchart for the bamboo fuel production method of the third embodiment. The bamboo fuel production methods of the second and third embodiments are different from the bamboo fuel production method of the first embodiment in that the soaking process is modified. In the second and third embodiments, the same parts as in the first embodiment are given the same reference numerals and their explanations are omitted, and only the parts that are different from the first embodiment will be explained.

[0119] <Second embodiment of bamboo fuel production method> As shown in Figure 6, the soaking process S23 of the second embodiment has a content measurement process S231 instead of the soaking period measurement process S301 in the soaking process S3 of the first embodiment, and this content measurement process S231 measures the potassium and chlorine content of the raw bamboo books 10 that are in a soaked state periodically from the start of soaking of the raw bamboo books 10, and maintains the soaked state of the raw bamboo books 10 until the measured value falls below a predetermined standard value.When the measured value falls below the predetermined standard value, it is considered that the production of the predetermined number of soaked bamboo books 20 has been completed, and the soaking process S23 is terminated.

[0120] There are various methods for measuring the potassium content and chlorine content. For example, the potassium content can be measured using an X-ray fluorescence analyzer, and the chlorine content can be measured using a residual chlorine meter, either singly or continuously.

[0121] <Third embodiment of bamboo fuel production method> As shown in Figure 7, the soaking process S33 of the third embodiment includes a content measurement process S231 in addition to the soaking period measurement process S301 of the soaking process S3 of the first embodiment. This content measurement process S231 measures the potassium and chlorine content of the raw bamboo books 10 that are in a soaked state periodically from the start of soaking of the raw bamboo books 10, and maintains the soaked state of the raw bamboo books 10 until the measured value falls below a predetermined standard value. If the measured value falls below the predetermined standard value, the soaking process S3 is terminated, assuming that the production of a predetermined number of soaked bamboo books 20 has been completed, even if the timing result of the soaking period measurement process S301 indicates that the predetermined period has not yet elapsed since the start of soaking of the raw bamboo books 10.

[0122] <Fourth embodiment of bamboo fuel production method> Figure 8 is a flowchart of the fourth embodiment of the bamboo fuel production method. The fourth embodiment of the bamboo fuel production method is different from the first embodiment in that the shape adjustment method has been changed. In the fourth embodiment, the same parts as in the first embodiment are given the same reference numerals and their explanations will be omitted, and only the parts that are different from the first embodiment will be explained.

[0123] As shown in Figure 8, the shape adjustment process S45 of the fourth embodiment includes a short bamboo booklet process S451 instead of the chipping process S501 of the shape adjustment process S5 of the first embodiment, and this short bamboo booklet process S451 processes and adjusts the long bamboo books 30 into short bamboo books to produce dried short bamboo books 80, which are then obtained as bamboo fuel 50.

[0124] The dried short bamboo packs 80 produced in this manner are in the form of the short bamboo packs described above, which makes them easy to handle when transporting as bamboo fuel 50 or putting into the combustion chamber.

[0125] Furthermore, as mentioned above, short bamboo books are not suitable for natural drying, and forced drying requires additional effort, labor, and energy consumption. However, the dried short bamboo books 80 of this embodiment can be naturally dried in the form of long bamboo books through the drying process S4 before being processed and adjusted into short bamboo books. Therefore, although the form is that of short bamboo books, there is no need for troublesome forced drying, and bamboo fuel 50 in the form of such short bamboo books can be easily produced.

[0126] The present invention has been described above based on an embodiment, but the present invention is not limited to the above embodiment, and it can be easily inferred that various improvements and modifications are possible within the scope of the present invention.

[0127] For example, in the first embodiment, multiple raw bamboo packs 10 were simply immersed in the water 22 stored in the water tank 21, but the immersion state of the raw bamboo packs 10 is not necessarily limited to this form, and an aeration means for aerating the water 22 stored in the water tank 21 may be provided in the water tank 21.

[0128] For example, the aeration means may include an air supply pump that is an air supply source, and an air bubble supply pipe that is installed in a submerged state in the water 22 in the water tank 21 from the air supply pump and releases air bubbles into the water 22, and the air supplied from the air supply pump through the air bubble supply pipe may be supplied as a large number of air bubbles into the water 22. The air bubble supply pipe may be a hose or other tubular body that supplies air bubbles into the water 22 in the water tank 21.

[0129] Furthermore, in the first embodiment, a mesh pallet 23 was used as an example of an underwater holding member, but such an underwater holding member is not necessarily limited to this, and any other means may be used as long as it can hold multiple raw bamboo packs 10 together and submerged in the water 22 at the same time.

[0130] Furthermore, in the second or third embodiment, the content of potassium and chlorine remaining in the raw bamboo booklet 10 or the soaked bamboo booklet 20 was measured by the content measurement process S231 in the soaking process S23 or the soaking process S33, but the measurement time point in such content measurement process is not necessarily limited to this, and for example, the content (including concentration) of potassium and chlorine remaining in the bamboo booklet 10, 20, 30 may be measured at one or more points in time after the bamboo splitting process S2, after the soaking process S3, or after the drying process S4. In this way, quality control regarding the potassium and chlorine content of the bamboo fuel 50 can be carried out more strictly.

[0131] In addition, the shape adjustment process S45 of the fourth embodiment includes a short bamboo booklet process S451 instead of the chipping process S501 of the shape adjustment process S5 of the first embodiment, but for example, both the chipping process S501 and the short bamboo booklet process S451 may be included in the shape adjustment process, so that both dried bamboo chips 40 and dried short bamboo books 80 are produced as bamboo fuel 50.

[0132] Furthermore, in the drying process S4 of the first to fourth embodiments, the soaked bamboo books 20 are dried using natural drying, but the drying method used to dry the soaked bamboo books 20 is not necessarily limited to natural drying; for example, forced drying, which requires more energy for drying than natural drying, may also be used. [Explanation of symbols]

[0133] 01 Raw bamboo 1 raw bamboo culm 2. Nodes on raw bamboo culms 3. Hollow part of live bamboo culm 4. Inner surface of raw bamboo culm 5. Outer surface of raw bamboo culm 10 Raw bamboo books 11 Cut surface of bamboo booklet 12. Inner arc of bamboo cover 13 Bamboo-shaped arched mask 20 Soaked Bamboo Book 21 Water Tank 22 water 23 mesh pallets 24 Suspension wire 30 Dry bamboo slips 31 Leaning stand 40 Dry bamboo chips 50 Bamboo fuel 60 Immersion water 70 Fertilizer for paddy rice 80 Dry short bamboo slips S1 Bamboo pretreatment process S2 Bamboo splitting process S3 Immersion process S4 Drying process S5 Shape adjustment process S6 Immersion water reuse process

Claims

1. A bamboo splitting process in which raw bamboo culms generated from raw bamboo are split into long bamboo culms to generate multiple raw bamboo culms; A soaking process in which the raw bamboo pieces produced in the bamboo splitting process are soaked in water for a predetermined period of time to dissolve potassium and chlorine from each raw bamboo piece into the water, thereby producing a plurality of soaked raw bamboo pieces in which the potassium and chlorine content of each raw bamboo piece has been reduced to below a predetermined standard value; After the soaking process, the soaked bamboo pieces are arranged in a vertical or inclined position and dried naturally or forcibly to produce a plurality of dried bamboo pieces. This bamboo fuel production method is characterized by including a shape adjustment process in which, after the drying process, the dried bamboo pieces, while still in a dry state, are crushed into chips or cut to a predetermined length, and the processed and adjusted form of dried bamboo chips or dried short bamboo pieces is obtained as bamboo fuel.

2. 2. The bamboo fuel production method according to claim 1, wherein the drying process is a natural drying process in which a plurality of soaked bamboo sachets are arranged in a vertical or tilted position and left to dry naturally in the sun or in the shade.

3. A bamboo fuel production method as described in claim 1 or 2, characterized in that it includes a soaking water recycling process in which the soaking water in which the raw bamboo stalks are soaked in the soaking process is recovered and the soaking water is reused as fertilizer for rice paddies or as a raw material for fertilizer for rice paddies.

Images