KR101662311B1 - Multipurpose dry apparatus for wood amd method - Google Patents

Abstract

The present invention provides a multipurpose wood drying method, designing a drying method appropriate for species of various lumber divided into hardwood and softwood by using a single wood drying apparatus and drying wood having a specific water content for a short period of time by using an operation method by using a hot air drying method or a low-temperature drying method or mixing the hot air drying method or a steam drying method.

Description

MULTIPURPOSE DRY APPARATUS FOR WOOD AMD METHOD BACKGROUND OF THE INVENTION 1. Field of the Invention < RTI ID = 0.0 >

The present invention relates to a wood drying apparatus and a drying method for drying a lumber, and more particularly, to a wood drying apparatus and drying method for drying lumber using a single wood drying apparatus, And can be used to dry various types of wood by using any one of an open drying method (hereinafter referred to as "hot drying method") or a low temperature drying method (hereinafter referred to as "steam drying method") And can design and operate drying conditions suitable for favorable modification by filling inert gas and rapid pressure elimination of the drying chamber, and a product thereof.

The present invention is a continuation-in-part application based on Korean Patent Application No. 10-2015-0046512.

Since the timber contains a large amount of wood moisture, the timber is not only heavy but also takes a long time to dry up to or below the drying water content during natural drying, and various dry bonding occurs in the drying process.

Therefore, from the viewpoint of protection and utilization of wood, the drying of sawn timber is a very important basic process in the timber processing, and drying of the timber or wood product to the water content that can be used during use minimizes drying damage due to shrinkage can do.

In other words, the sawn timber should be dried and used below the average moisture content of the place of use.

In wood, the rate of increase in strength due to decrease in water content differs depending on the strength. Compressive strength and bending strength of wood are two times larger than those of raw materials, and artificial drying is increased about 3 times as much as water .

When wood is used in the production of wood products such as furniture, flooring and cooking utensils, the lumber can be treated with chemicals and / or heat (drying) for the purpose of increasing its durability before use.

In recent years, artificially dried wood through chemical techniques using boric acid has been developed as a heat treatment technique for more durable production of wood as the number of importing countries is increasing due to environmental problems of borate.

The main reason for drying the wood is to ensure dimensional stability before using the wood in subsequent manufacturing such as building or furniture production. The drying process is essential for the economical utilization of wood in construction, wood-based manufacturing and craft applications, and its value is very high.

Normally, the raw material (shaved wood) contains water in the cell wall, but the voids such as the cell gap or the cell lumen are not completely filled with the liquid phase, but only a part exists. The water content of the raw materials varies depending on the species, the mountain area, the season, the area of the towel, etc. However, the moisture content of the broad-leaved trees is about 45 to 160%, but most species of the coniferous and broad-leaved trees are in the range of 30 to 200%.

The water is divided into the free water existing in the lumen of the cell and the binding water present in the cell wall. The free water has no binding relationship with the cytoplasmic wall and is simply moved by capillary attraction and maintained by the cohesive force between the water molecules, Is bonded to the cell wall by the hydrogen bond Van der Waals force, so that the bonding water is difficult to transfer water and requires heat to be removed, and the increase and decrease of the bonding water is due to the physical / mechanical properties , Moisture is very important when processing and using wood.

Currently, the drying of lumber uses a low temperature steam heating and drying system. Such a conventional low temperature steam heating and drying system is equipped with a sealed drying chamber which can be controlled in terms of temperature, humidity and air circulation so that the conditions of the air, if necessary, accelerate or delay the drying process.

However, the conventional drying method using the low-temperature steam heating and drying system has a considerably long treatment time, that is, depending on species, but drying of the rubber tree requires a total period of 10 to 13 days, For example, conventional drying methods have obvious drawbacks that require 2 to 4 times the minimum energy required to evaporate water.

For example, GB Patent 1,142,525 discloses a method of drying hardwood in a drying chamber comprising spraying steam and water spraying at a temperature of between 21 ° C and 66 ° C (70 ° F to 150 ° F) The same conventional drying method takes 14 days to complete drying.

In addition, since the conventional low temperature steam drying method described above is characterized by super heated vapor drying in which air is excluded and kept at a wet bulb temperature of 100 DEG C in a sealed state, a high-temperature drying Hardwood species such as Basswood, Birch, Soft maple, Red oak, Yellow-popler and Black yuprlo, which are more useful for the drying of woody plants, There is a problem in that it is necessary to separately install a drying device suitable for the drying process.

In other words, the lumber is generally classified as hardwood (non-terminal lanceolate) or softwood (softwood) type. Since hardwood has a more complicated structure than softwood, and there are pores or blood vessels in the wood, heat treatment or drying of hardwood lumber More sophisticated control of temperature and humidity, ie a dry drying room with a significantly different design than drying of the lumber, is effective for the high throughput of high-quality dry lumber that will be derived from low density to medium density tropical hardwood A drying method and a drying method of a sawn timber capable of integrally operating the drying of a softwood are required.

The above-described conventional drying apparatus is described in detail in Japanese Patent Registration No. 10-0948625 and Japanese Patent Application Laid-Open No. 10-2013-0054833.

The present invention relates to a multi-purpose wood drying apparatus capable of drying and high-temperature processing wood having a water content required by various kinds of timber, Drying method and a product thereof.

The present invention provides a multi-purpose wood drying apparatus, a drying method, and a product thereof, which are capable of mixing or selectively operating an atmosphere of a drying room with an open drying method and a steam drying method.

The present invention promotes the dehydration of free water and binding water present between the intracellular lumen and the cell membrane in the wood by the inert gas pressure filled in the drying chamber and the pressure impact caused by the rapid pressure removal during the drying of the shredded wood by the steam drying method, And an inert gas filling device capable of increasing the drying efficiency of the wood and reducing the drying time, and a product therefor.

The shrub-tree drying apparatus according to the present invention, as described in claim 1,

An open dryer 104 installed on the inner wall of the drying chamber 101 for raising the temperature of the drying chamber to a predetermined range;

A steam generator 110 for generating a steam pressure in a drying chamber 101 provided on a bottom surface of the drying chamber 101;

A drying chamber pressurizing device 130 connected to the inside of the drying chamber to raise the internal pressure of the drying chamber 101 to a predetermined range;

A pressure eliminator 120 connected to the drying chamber so as to temporarily erase the pressure of the drying chamber;

An inert gas filling device 150 for filling an inert gas into the drying chamber 101;

A cooling water sprinkling device (140) installed at an upper portion of the drying chamber (101) to cool the heated shavings;

The inert gas filling apparatus 150, the pressure eliminator 120, the drying chamber pressurizing apparatus 130, the drying chamber 104, the drying chamber 104, And a controller (10) for controlling the controller (10).

The drying chamber may further include a blower capable of forming an air flow.

The steam generating apparatus of the present invention can heat a container containing water on the bottom surface of a drying chamber with a drying device (boiler) to form a vapor pressure in the drying chamber. The vapor pressure, the internal temperature and the humidity are measured by a pressure sensor, a temperature sensor, a hygrometer ), And the detected signal is transmitted to the controller to control the pressure, temperature, and humidity of the drying chamber.

In the present invention, an inert gas is filled into a drying chamber, the pressure is raised by a drying chamber pressurizing device, the pressure is rapidly removed through a pressure eliminator, and then the temperature of the drying chamber is maintained for a predetermined time in an open drying method and / It is characterized by drying with good quality wood by equalization and conditioning of lumber.

The present invention is characterized in that it further comprises a drying chamber pressurizing device for arbitrarily increasing the pressure in the drying chamber. The pressurizing device of the drying chamber is used for increasing or decreasing the internal pressure of the drying chamber, either of a pneumatic type or a volumetric type.

In addition, the pressure of the drying chamber can be improved by eliminating the pressure in the drying chamber at a time, thereby eliminating the free water and bound water present in the cell lining and cell membrane of the sawn timber heated by the pressure shock.

The method for drying a timber according to the present invention comprises:

(a) placing the above-mentioned rubber-wood-clad laminate on a perforated plate at a predetermined height, placing a weight of 150 kg on the upper surface of the laminated clippings, sealing the drying chamber with a lid in a drying chamber;

(b) The steam drying method and the hot drying method are selected through the operation mode setting part of the controller, and the temperature of the drying chamber by the hot air drying method is set to 120 to 150 ° C. The operation time is set to 21 hours, the inert gas filling pressure is 4.2 to 4.4 hPa, the inert gas filling pressure holding time is set to 2 hours by the second timer, and operation is started;

(c) After 21 hours, the controller charges the inert gas with an inert gas filling device so that the pressure in the drying chamber is maintained at 4.2 to 4.4 hPa, and then, the drying chamber is dried by the steam drying method and the hot drying method (b), the controller operates the pressure eliminator to rapidly remove the pressure in the drying chamber after a predetermined time has elapsed;

(d) performing the equilibration and conditioning while maintaining the pressure in the drying chamber at 4 hPa with the drying chamber pressurizing device while operating the steam generator and the hot-air drying device in the temperature range set in the step (b) for 4 hours; Wow;

(e) slowly discharging the pressure in the drying chamber to remove the cooling water, and then cooling water to the top of the sawn wood through a sprinkling device to cool the sawn wood;

(f) drawing the parquet out of the drying chamber to naturally dry the cooling water, and then processing the dried rubber wood into the finished product.

The present invention can be formed by using a drying device to open an atmosphere in a drying chamber or a mixture of steam or heat and steam, thereby realizing a drying condition suitable for a modification favorable to a steam drying method.

According to the present invention, it is possible to dry the sawn timber by using heat or steam or heat and steam depending on the species in the drying room. In particular, the sawn timber can be dried by the steam generating apparatus using the steam drying method using the atmosphere in the drying chamber.

In the present invention, dehydration of the free water and binding water existing between the cell lumen and the cell membrane in the wood is promoted by the inert gas filled in the drying of the sawn timber by the steam drying method and the rapid pressure removal, The escape of free water and binding water can be improved, and the effect of interfacial collapse and celluloid removal of cells is enhanced.

The present invention can be operated selectively or mixed according to conifer or hardwood species through the hot drying method and the steam drying method, and it is possible to precisely control the pressure and the temperature control, so that a large amount of wood can be dried in a short time, The drying quality can be improved.

In the present invention, when the water content of the sawn timber reaches the target point, the temperature of the drying chamber is maintained at a constant temperature for a predetermined time and at a constant pressure to perform equalization and conditioning of the sawn timber, Can be precisely designed.

Therefore, the present invention can provide a treated wood having a water content of 3 to 6% after treating the shrub with a fresh water content of 36 to 28% before the treatment, and by the equalization and conditioning of the dried wood, There is an effect that a stable wood can be produced at the time of use or processing.

According to the present invention, the drying conditions of various types of timber can be derived from the following examples, and the drying conditions of several kinds of timber can be further designed by applying the following embodiments.

1 is a longitudinal sectional view schematically illustrating a general purpose wood drying apparatus according to the present invention, Fig.
Fig. 2 is a longitudinal sectional view illustrating an example of an open dryer installed in the multi-purpose wood drying apparatus shown in Fig. 1. Fig.
FIG. 3 is a longitudinal sectional view illustrating a drying chamber pressurizing apparatus mounted on the multi-purpose wood drying apparatus shown in FIG. 1,
Fig. 4 is a longitudinal sectional view illustrating a pressure-erasing apparatus mounted on the multi-purpose wood drying apparatus shown in Fig. 1,
FIG. 5 is a vertical cross-sectional view illustrating an inert gas filling apparatus mounted on the multi-purpose wood drying apparatus shown in FIG. 1,
FIG. 6 is a longitudinal sectional view illustrating an example of a sprinkling device mounted on the multi-purpose wood drying apparatus shown in FIG. 1. FIG.
7 is a block diagram illustrating a detailed configuration of a controller of a multi-purpose wood drying apparatus according to the present invention.

Hereinafter, preferred embodiments of a wood drying apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic longitudinal sectional view of a multi-purpose wood drying apparatus 100 according to the present invention. The wood drying apparatus 100 according to the present invention includes a drying chamber 101 (see FIG. 1) in which a pallet 105, A steam generator 110 mounted on a bottom surface of the drying chamber 101, an open dryer 104 installed in the drying chamber 101, a drying chamber pressurizing device 130, an inert gas filling device 150, And includes a pressure eliminator 120 and a water sprinkler 140.

The drying chamber 101 is a space for receiving the sawing material, and a lid (not shown) for sealing the drying chamber 101 is coupled to one side of the drying chamber 101. The drying chamber 101 may have various shapes. However, the present invention is exemplarily shown in the drawings as a capsule type in which the drying chamber is hermetically sealed.

The drying chamber 101 is provided with a water tank 103 in which steam is generated by a boiler on the bottom surface of the drying chamber 101. The drying chamber 101 is provided with guide rails 103, And a guide rail 105a is installed on the guide rail 105a so that the pallet 105 having a predetermined height at a predetermined height can slide in and out of the drying chamber 101. [

 The drying chamber 101 includes a shell 104b made of a steel sheet having a sufficiently large thickness and a refractory brick 104a on the inner surface of the shell 104b and an open dryer 104 is installed in the refractory brick 104a Is installed.

The water tank 103 is heated by the steam generator 110 (boiler), the heated steam is introduced into the drying chamber 101 through a steam outlet (not shown), and the other part of the water tank 103 It is closed.

The water tank 103 may include a water supply pipe (not shown in the figure) and a drain valve (not shown in the figure) that can discharge the water stored therein.

Referring to FIG. 2, FIG. 2 is a vertical cross-sectional view illustrating an example of the hot-air drying apparatus 104 mounted on the multi-purpose wood drying apparatus 100 shown in FIG. 1. The hot- The drying device 104 is used to operate the drying device in combination with any one of the steam drying method by the heat drying method and the steam drying method by the steam drying method, The operation can be controlled by sensing a temperature sensor (not shown in the figure) that is provided on the inner wall of the drying chamber 101 and generates heat by the power source and senses the ambient temperature in the drying chamber 101.

That is, when the sensed value sensed by the temperature sensing sensor is larger than the set value in comparison with the set value of the controller 10 (see FIG. 7) described below, the power supply is shut off by the controller 10 (see FIG. 7) And if it is the opposite, the temperature in the drying chamber 101 can be controlled by supplying power.

The hot air drying apparatus 104 and the steam generating apparatus 110 may be operated together or selectively in accordance with the operation mode of the operator's controller 10. In this case, ), It is effective to reduce the drying time by about 28%.

Referring to FIG. 3, FIG. 3 is a longitudinal sectional view illustrating a drying chamber pressurizing apparatus mounted on the multi-purpose wood drying apparatus shown in FIG. 1, wherein the drying chamber pressurizing apparatus 130 pressurizes the pressure in the drying chamber 101 to a predetermined pressure The drying chamber pressurizing apparatus 130 may be a pneumatic system for forcedly introducing air into the drying chamber 101 from the outside to raise the air pressure inside the drying chamber arbitrarily, Or a volumetric method in which the internal volume of the drying chamber is increased by pushing in the volumetric water 131 having a predetermined volume.

FIG. 3 illustrates the implementation of the drying chamber pressurizing device in a volumetric manner. In the pneumatic process, as the internal pressure of the drying chamber is increased, the pneumatic pressure must be larger. Therefore, energy consumption is large and the pneumatic line is damaged. However, such a problem is advantageous in that it can overcome all of the volumetric methods.

In Fig. 3, reference numeral 130 denotes a hydraulic cylinder, and 131 denotes a volume to be inserted into the drying chamber 101 by the operation of the hydraulic cylinder. A plurality of the hydraulic cylinders 130 may be installed on the outer surface of the drying chamber 101. The volume of the hydraulic cylinders 130 may be different from each other so that the pressure of the drying chamber can be controlled differentially.

The hydraulic cylinder 130 is controlled (turned on / off) by the controller 10 (see FIG. 7), and the operation time can be selectively operated according to the drying species.

4 is a vertical cross-sectional view illustrating an example of a pressure eliminator installed in the multi-purpose wood drying apparatus shown in FIG. 1. The pressure eliminator 120 removes the pressure in the drying chamber 101 at a time And is useful for discharging the moisture present in the cell membrane and intracellular lumens of the sawn wood to the outside of the wood.

The pressure eliminator 120 includes a pressure pipe 121a coupled to the periphery of the drying chamber 101 and a pressure outlet 121 branched from the pressure pipe 121a and coupled to be disposed in the drying chamber 101 .

A pressure regulating damper (not shown) having a solenoid valve (not shown in the drawing) is connected to the pressure line 121a of the pressure eliminator 120.

The damper buffers the generated pressure and noise when the pressure in the drying chamber is rapidly removed.

The pressure pipe 121a can automatically discharge the overpressure to the front of the solenoid valve through the discharge valve to protect the drying chamber.

In the drawing, reference numeral 122 denotes a pressure discharge pipe in which a pressure pipe through which a plurality of pressure discharge ports 121 are gathered is connected to the above-described damper.

Referring to FIG. 5, FIG. 5 is a vertical cross-sectional view illustrating an inert gas filling apparatus 150 mounted on the multi-purpose wood drying apparatus 100 shown in FIG. 1. The inert gas filling apparatus 150 includes an open- Or steam drying method, the inert gas is filled into the drying chamber 101 to facilitate permeation of water vapor and pressure into the cell membrane and the intracellular cavity of the sawn timber, that is, to promote the discharge of wood moisture Can be employed. In the drawing, reference numeral 151 denotes a nozzle into which an inert gas flows.

The inert gas may have any one of nitrogen, neon, argon, krypton, xenon, radon, and helium, preferably nitrogen, which is advantageous in terms of cost.

Referring to FIG. 6, FIG. 6 is a longitudinal sectional view exemplifying a spraying apparatus 140 mounted on the multi-purpose wood drying apparatus shown in FIG. 1, in which a spraying apparatus 140 is provided for cooling the heated dried wood And includes a cooling water distribution pipe 141a coupled to a sprinkling nozzle 141 for sprinkling water supplied from the outside on the sawn wood W2 at an upper portion of the drying chamber 101. [ Reference numeral 142 denotes a cooling water inlet.

The water sprinkled by the sprinkling nozzle 141 can be opened and closed by a solenoid valve (not shown) attached to the cooling water distribution pipe 141a to which the spray nozzles 141 are connected. The above solenoid valve is controlled by the controller 10 (see Fig. 7).

Referring to FIG. 7, FIG. 7 is a block diagram illustrating a detailed configuration of a controller of a multi-purpose wood drying apparatus according to the present invention.

The controller 10 includes an operation mode setting unit 11 that can select an open drying method, a steam drying method, or a drying method using them in combination, a temperature setting unit 12 for setting an atmospheric temperature in the drying chamber 101, A setting section 10a including a pressure setting section 13 for setting the atmosphere pressure in the drying chamber 101 and an atmosphere holding time setting section 14 for maintaining the temperature and pressure in the drying chamber 101, And a sensing unit 20 including a temperature sensing sensor and a humidity sensing sensor for sensing the pressure and temperature in the sensing unit 20 and transmitting the sensing value to the controller 10, And determines whether the steam generating apparatus 110, the hot air drying apparatus 104, the drying chamber pressurizing apparatus 130, the inert gas filling apparatus 150, the pressure erasing apparatus 120, the water spraying apparatus 140 are operated Or a plurality of timers (not shown in the drawing) As shown in FIG. The timers can be selected and set by the operator when the operation mode is set with respect to the operation time of the drying apparatus.

In general, since the drying of the lumber is different depending on the species, the thickness, the type of the drying chamber, and the parameters of the protocol (drying schedule), the present invention excludes the parameters of the protocol and the same specimen is used in the present invention and the conventional low- The time required for reaching the object is experimented, and the effect of the detailed configuration of the present invention will be explained through the result.

In order to confirm the drying efficiency of the sawn timber of the present invention, the sawn timber specimen and the drying chamber are operated under the same conditions under the following standard.

According to the present invention, different kinds of wood (oak, acacia, birch, bark, chestnut, rubber tree) cut into different sizes of hardwood species at a size of 30 (T) x 100 (W) x 600 mm (15 kg) was placed on the top of the timber, and the wet bulb temperature of the air-tight drying chamber (101) was set to 130 ± 5 ° C and the dry bulb temperature was set to 120 ° C And the drying of the sawn timber is started in parallel with the steam drying method and the hot drying method. The drying chamber is equipped with a blowing fan, but it can be operated as a variable in the drying time, so that the operation of the blower is excluded in the experiment.

14 hours to 16 hours after the start of the operation, the nitrogen gas was filled into the drying chamber 101 so as to maintain the pressure of 4.3 at a time, and then the pressure in the drying chamber was atmospheric pressure at a time (hereinafter referred to as "inert gas filling method" After drying, the drying time was measured to reach 4 ± 5% of the dry weight of each sawn timber in the same condition as above.

Meanwhile, in the conventional low temperature steam drying method, the time when the drying water content of the sawn timber reaches 4 +/- 5% is measured by the operation of the present invention by the steam drying method except for the hot dry method and the inert gas filling method of the present invention Respectively.

The water content is calculated by the following equation.

[Experimental Example 1]

Table 1 below shows the results of checking the drying time when the moisture content reaches 4 ± 5% through the steam drying method, the hot drying method and the inert gas filling method in the operation according to the drying of the stomach.

Drying time to reach a water content of 4 ± 5% Species Conventional low temperature steam drying method Invention kind of oak 72 hours 23 hours acacia 71 hours 27 hours Birch 69 hours 23 hours Fir tree 71 hours 23 hours chestnut 75 hours 26 hours Rubber tree 74 hours 27 hours

[Experimental Example 2]

Table 2 below shows the results of checking the drying time at which the moisture content reaches 4 ± 5% by operating the above conditions using only the above-mentioned steam drying method and inert gas filling method except for the hot drying method. .

Drying time to reach a water content of 4 ± 5% Species Conventional low temperature steam drying method Invention kind of oak 72 hours 38 hours acacia 71 hours 42 hours Birch 69 hours 43 hours Fir tree 71 hours 39 hours chestnut 75 hours 34 hours Rubber tree 74 hours 37 hours

[Experimental Example 3]

Table 3 below shows the results of examining the drying time at which the water content of the specimen reaches 4 ± 5% by operating the above-mentioned conditions by only the hot drying method and the inert gas filling step without the above steam drying method, 3.

Drying time to reach a water content of 4 ± 5% Species Conventional low temperature steam drying method Invention kind of oak 72 hours 44 hours acacia 71 hours 48 hours Birch 69 hours 49 hours Fir tree 71 hours 41 hours chestnut 75 hours 42 hours Rubber tree 74 hours 42 hours

[Experimental Example 4]

Table 4 below shows the results of examining the drying time at which the water content of the various kinds of the sawn timber reaches 4 5% by using the steam drying method and the hot air drying method, excluding the above-mentioned inert gas filling method, as shown in Table 4 below .

Drying time to reach a water content of 4 ± 5% Species Conventional low temperature steam drying method Invention kind of oak 72 hours 70 hours acacia 71 hours 69 hours Birch 69 hours 66 hours Fir tree 71 hours 66 hours chestnut 75 hours 72 hours Rubber tree 74 hours 73 hours

In comparison with the results of Experiments 1 to 4, when the drying process of the test piece is operated only by the results of Table 4, that is, the steam drying method and the hot drying method, the reaching time of the target drying water content is lower than that of the conventional low temperature steam drying method Although there is no difference except that the thermal efficiency is excellent, there is a marked difference in the results in Table 1, namely, the steam drying method and the drying method of the saddle wood in combination with the heat drying method and the inert gas filling step.

Comparing the results in Table 2 with those in Table 1, the results in Table 2 show that the time to reach the target water content is delayed relative to the results in Table 1 (steam and hot air drying and inert gas filling) It can be seen that the drying time is further shortened in the steam drying method and the inert gas filling method as compared with the conventional low temperature steam drying method.

In addition, the results of Table 3 are compared with those of the other tables. The results of Table 3 are lower than those of Table 1, but the drying speed is higher than the results of Table 4 and Table 2, The drying method of the shredded wood by the impact method is confirmed to be a factor for shortening the drying time as compared with the conventional low temperature steam drying method.

Table 5 below shows micrographs of oak taken from the species listed in Table 1 above and the texture of the conventional low temperature steam drying method and the texture of the specimen before and after treatment by the above test at 1,000 times.

Conventional low temperature steam drying method Invention   In the above picture, S1 is the cell lumen and S2 is the cell wall.

In general, the difficulty of moisture diffusion of the sawn timber is inversely proportional to the density and the diffusivity is almost proportional to the density. However, when the inert gas is operated in parallel with the steam drying method (see Table 2) (Table 3), it can be judged that inert gas particles accelerate the penetration of heat and water vapor from the surface of the wood into the interior.

The above picture shows that when the lumber is heated at high temperature, the free water is heated to above the boiling point and pressure is generated inside it, and the resulting steam pressure causes the hydrodynamin flow of water vapor to the opposite side from the swirling line, To the wood surface, due to the rapid removal of the inert gas filling pressure, rapidly escapes to the surface of the wood due to the pressure of the compressed steam and the pressure in the drying chamber deeply penetrating the interior of the lumber, collapsing the cell wall, It is considered that the free and combined numbers existing in the region rapidly escape.

Prior to the experimental examples shown in Tables 1 to 4, while the preliminary experimental conditions were set, the energy consumption was further delayed compared with the drying time of Table 1 below 4 hPa, and the energy consumption was increased above 4.5 hPa, In the experiment, the pressure of the drying chamber was set to 4.3 hPa on average.

The results of the gastric micrograph and the results of Tables 1 to 4 indicate that the water contained in the intracellular cavity S1 and the water present in the cell wall S2 are mostly dehydrated, It is observed that the boundary between the cell lumen and the cell membrane is clearly changed in the form of an empty tree, so that the drying process of Table 1 described above is very useful.

Particularly, the initiation time of the inert gas filling of the drying chamber and the method of promoting the water movement by the pressure shock due to the proper depressurization and the rapid depressurization can be performed by the person skilled in the art to which the present invention pertains, There will be no difficulty in deriving the detailed operating conditions suitable for the present invention.

However, since the inert gas and the rapid pressure removal according to the present invention promotes moisture transfer, the amount of deformation such as hardness, cracking, and twisting of the wood is about 0.4% larger than that of the conventional low temperature steam drying method. The free water and bound water in the lumen of the cell are predicted to be dry defects due to the collapse of the cell wall and cell lumen as rapid dehydration proceeds. However, the energy efficiency and labor cost in drying, the efficiency of mass production, Due to the nature of the drying operation, some manufacturing defects do not appear to be a major defect in employing the present invention.

Hereinafter, a drying method for treating the water content of rubber trees classified as hardwood through the drying apparatus of the present invention to 4 5% will be described.

[Example]

The rubber wood shavings are 30 (T) x 100 (W) x 1800 mm (L), and the size of the drying chamber is 12 times the size of the drying chamber as described above.

The size of the above-mentioned rubber wood is a common timber when producing wood such as flooring or flooring.

(a) Placing the above-mentioned rubber wood lumber on a parquet plate at a predetermined height (2.9 m), placing a 150 kg weight on the top of the flat lumber, putting the parquet in the drying chamber (101) and sealing the drying chamber with a lid Seal it.

The heavy material described above can prevent deformation due to thermal deformation, shrinkage or warping of the sawn timber when drying the sawn timber. The weight of the heavy material may be appropriately selected by the operator corresponding to the stacking height of the sawn timber.

(b) The steam drying method and the hot drying method are selected through the operation mode setting part of the controller, and the temperature of the drying chamber by the hot air drying method is set to 120 to 150 ° C. The operation time is set to 21 hours, the inert gas filling pressure is 4.2 to 4.4 hPa, and the second timer is set to the inert gas filling pressure holding time of 2 hours, and operation is started.

The sensing signals of the temperature sensor, the pressure sensor, and the humidity sensor are transmitted to the controller, and the operation of the steam generator and the heat drying apparatus is controlled by the controller.

(c) When 21 hours have elapsed, the controller charges the inert gas with an inert gas filling device so that the pressure in the drying chamber 101 is maintained at 4.2 to 4.4 hPa, and then the drying chamber is subjected to steam drying, The controller operates the pressure eliminator to rapidly erase the pressure in the drying chamber. As the inert gas, any one of the above-mentioned gases can be selected. In the present invention, nitrogen gas was selected.

As the number of times the pressure of the drying chamber is lowered at atmospheric pressure at a time, the rubber tree may cause drying defects. Therefore, it is preferable to perform the pressure shock process 1 to 2 times.

In the case where the pressure shock process is performed twice, the operation mode of the controller is set so as to repeat the above-described inert gas filling process (step (c)).

(d) While operating the steam generator, keep the pressure of the drying chamber at 4 hPa with the drying chamber pressurizer for 4 hours.

In the above-described drying chamber pressurizing device, the hydraulic cylinder is operated under the control of the controller described above, and the volumetric water enters into the drying stall. This is advantageous in that it is not necessary to raise the pressure of the drying chamber by the same principle as pushing a volume having a specific volume into the balloon, and it is possible to precisely and easily control the pressure.

When the pressure of the drying chamber is maintained at 4 hPa for 4 hours, the moisture content of the rubber tree is about 6% to 8% when the pressure of the drying room is rapidly removed. Therefore, the atmosphere is formed at a relatively low pressure compared to the dehydration pressure, % Before reaching the end of the cycle.

For reference, the equilibration is carried out in order to prevent the variations that occur during storage, processing or use of the treated rubber tree, and the conditioning is to alleviate the drying stress of the rubber tree and to remove the moisture and to equalize the water content of the thickness.

(e) The pressure in the drying chamber (101) is gradually discharged and removed, and then cooling water is sprinkled to the upper side of the sawn timber through a sprinkling device to cool the sawn timber.

(f) The parquet is taken out from the drying chamber 101, the cooling water is naturally dried, and the dried rubber wood is processed into a finished product.

As described above, according to the present invention, it is possible to design a protocol suitable for the advantageous modification by filling the inert gas with the drying atmosphere or by using steam in combination, or by instantaneous pressure elimination in the drying room.

Also, according to the present invention, it is possible to operate the drying process of the sawn timber by using heat, steam, or heat and steam in combination, depending on the species of the drying room. In particular, the sawn timber can be dried by the steam generating device.

In addition, the present invention accelerates the dehydrating effect of moisture existing between the intracellular cavity and the cell membrane due to the inert gas filled in the drying of the shredded wood by the steam drying method, the pressure of the drying chamber and the pressure change caused by the rapid pressure removal, It is possible to provide a process advantageous for designing the target moisture content.

Claims (3)

In the method for drying a sawn timber,
(a) Placing the rubber wood shavings on the parquet with a predetermined height and placing a heavy load of 150 kg on the upper surface of the laminated shavings, placing the parat in the drying chamber 101 and sealing the drying chamber to be sealed with a lid Wow;
(b) a steam drying method and an open drying method are selected through an operation mode setting part (11) of the controller, and the temperature of the drying chamber is adjusted to 120 - The operation time of the steam generator and the hot-air drying apparatus was set to 150 ° C with the first timer for 21 hours, the inert gas filling pressure was 4.2 to 4.4 hPa through the pressure setting unit 13 of the controller, Time and 2 hours, respectively, and start the operation;
(c) When the operating time set in the step (b) has elapsed, the controller charges the inert gas with an inert gas filling device so that the pressure in the drying chamber 101 is maintained at 4.2 to 4.4 hPa, The controller sets the temperature set in the step (b) to a temperature range of 120 to 150 ° C for 2 hours through the steam drying method and the hot drying method under the above-described atmospheric conditions, Thereby rapidly removing the pressure of the drying chamber;
(d) performing the equalizing and conditioning operation by operating the steam generator and the hot air drying apparatus at the temperature range set in the step (b) for 4 hours at a pressure of 4 hPa with the drying room pressurizing apparatus;
(e) slowly discharging the pressure in the drying chamber (101) and removing cooling water from the upper part of the sawn wood through a sprinkling device to cool the sawn wood;
(f) drawing the parquet from the drying chamber (101) to naturally dry the cooling water, and then processing the dried rubber wood into a finished product. The method according to claim 1,
Wherein the inert gas is one of nitrogen, neon, argon, krypton, xenon, radon or helium gas. delete

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