CN112454576A

CN112454576A - Wood modification heat treatment process and treatment equipment

Info

Publication number: CN112454576A
Application number: CN202011329252.0A
Authority: CN
Inventors: 周明武; 王雄
Original assignee: Hunan Weidal Wood Technology Co ltd
Current assignee: Hunan Weidal Wood Technology Co ltd
Priority date: 2020-11-24
Filing date: 2020-11-24
Publication date: 2021-03-09

Abstract

The invention discloses a wood modification heat treatment process, which comprises the following steps of firstly, placing wood blanks on a trolley at intervals, vertically stacking a plurality of layers, applying downward pressure on the top of the trolley to enable all the parts of the wood blanks to be stressed evenly and to be kept flat, and then sequentially carrying out the following steps: s1, nitrogen replacement and preheating treatment: vacuumizing the kiln, replacing nitrogen and preheating; s2, temperature rising treatment: heating and dehumidifying the kiln; s3, deep drying treatment: completely drying the inside of the furnace; s4, vacuum microwave carbonization: carrying out vacuum microwave carbonization treatment in the furnace; s5, slow cooling treatment: slowly cooling under the protection of nitrogen; s6, quick cooling treatment; s7, rewetting treatment: and introducing steam into the furnace to enable the blank to reach a certain water content, and then taking out of the kiln. The invention also provides a treatment device for the treatment process, and aims to reduce the influence of high-temperature carbonization on the color of the wood on the premise of ensuring the dimensional stability of the wood.

Description

Wood modification heat treatment process and treatment equipment

Technical Field

The invention relates to the technical field of wood heat treatment, in particular to a wood modification heat treatment process and treatment equipment.

Background

Due to the biological characteristics of wood, products thereof have the phenomena of dry shrinkage, wet swelling, easy deformation and cracking and the like during use, and in order to improve the problems, modification treatment is generally carried out on the wood.

Wood modification refers to physical or (and) chemical processing methods that improve or alter the physical, mechanical, chemical, and structural characteristics of wood. Its purpose is to improve the natural decay (moth) resistance, acid resistance, alkali resistance, fire resistance, wear resistance, colour stability, mechanical strength and size stability of wood. The wood modification technology comprises the following steps: wood acetylation, wood heat treatment, wood compression and bending, wood bleaching and dyeing, and other modification techniques.

During the heat treatment modification process of the wood, hemicellulose and the like with strong hygroscopicity in the wood are changed at high temperature to generate polymers with weak hygroscopicity, so that the dimensional stability can be effectively improved, and the method is an effective method for improving the corrosion resistance of the wood. Because no chemical agent is needed in the treatment process, the method has the characteristic of better environmental protection performance.

However, in the prior art, in the heat treatment modification of wood, the heat treatment temperature is generally controlled to be more than 200 ℃ under the condition of ensuring the dimensional stability of the wood, so that on one hand, the mechanical property of the wood is inevitably reduced, and the service performance is influenced; on the other hand, the higher heat treatment temperature leads to the deepening of the color of the wood, which affects the market application of the heat treatment modified wood and can not meet the requirements of users. If the temperature in the heat treatment process is only reduced, the wood can not meet the modification requirement, so that the prior wood heat treatment modification process needs to be optimized and improved.

Disclosure of Invention

In view of the above, the present invention provides a wood modification heat treatment process and a wood modification heat treatment apparatus, so as to reduce the influence of high temperature carbonization on the color of wood on the premise of ensuring the dimensional stability of wood.

In order to achieve the above object, in a first aspect, the present invention provides a wood modification heat treatment process, in which wood blanks are placed on a trolley at intervals, stacked in multiple layers vertically, and a downward pressure is applied to the top of the trolley to keep the wood blanks flat, and the wood blanks are sequentially subjected to the following steps:

s1 replacement of Nitrogen and preliminaryAnd (3) heat treatment: moving the trolley loaded with the wood blank into a kiln, closing the kiln, vacuumizing the kiln, and controlling the pressure at 10^-3Under Mpa; then, protective gas is filled into the furnace until the pressure in the furnace is micro-positive pressure; starting an atmosphere heating device in the furnace for preheating, wherein the temperature is 30-50 ℃;

s2, temperature rising treatment: heating to 30-100 ℃, controlling the heating speed to be 3-10 ℃/h, controlling the humidity range to be 50-100%, controlling the oxygen content range to be 0.1-2%, controlling the treatment time to be 3-10 h, opening an exhaust port of the kiln, and maintaining the micro-positive pressure in the kiln;

s3, deep drying treatment: the drying treatment temperature in the furnace is raised to 100-150 ℃, the temperature raising speed is controlled to be 3-5 ℃/h, the oxygen content is controlled to be 0.1-1%, the treatment time is 5-25 h, and the micro-positive pressure in the furnace is kept;

s4, vacuum microwave carbonization: closing the furnace atmosphere heating device and the exhaust port, and vacuumizing the furnace, wherein the vacuum degree is kept at 0.5 multiplied by 10^-2~5×10^-2Mpa; starting a microwave carbonization device, wherein the carbonization treatment temperature is 160-200 ℃, the temperature rise speed is controlled to be 5-10 ℃/h, the oxygen content is 0.1-1%, and the treatment time is 5-10 h;

s5, slow cooling treatment: closing the microwave carbonization device, introducing protective gas into the kiln until the pressure is micro-positive pressure, slowly cooling at 120-130 ℃, and controlling the cooling speed at 5-10 ℃/h;

s6, quick cooling treatment: starting a cold air circulating device to reduce the treatment temperature in the kiln to 60-100 ℃;

s7, rewetting treatment: and (3) introducing steam into the kiln, controlling the treatment temperature in the kiln to be 40-60 ℃, controlling the humidity range to be 50-100%, and controlling the water content of the wood blank to be 6-10%, and then discharging the wood blank out of the kiln.

Further, the moisture content of the wood blank after being processed by S3 is reduced to below 1%.

Further, the micro-positive pressure is 200-400 Pa higher than the atmospheric pressure.

Furthermore, circulating air is introduced into the kiln.

Further, the protective gas is nitrogen.

In a second aspect, the present invention also provides a treatment apparatus for the above wood modification heat treatment process, comprising: the system comprises a kiln, a trolley, an in-kiln atmosphere heating device, a microwave carbonization device, a vacuum pump, a nitrogen source, a cold air circulating device, a steam source and an exhaust port, wherein the vacuum pump, the nitrogen source, the cold air circulating device, the steam source and the exhaust port are communicated with a pipeline in the kiln;

the microwave carbonization device comprises: the microwave source and rather than the crack antenna of being connected, the crack antenna stretches into to in the kiln to the equipartition interval sets up a plurality of platform trucks both sides in the kiln, and the gap on the crack antenna is towards the platform truck.

Further, the furnace atmosphere heating apparatus includes: the heat-conducting oil heating tank is arranged on the inner side wall of the kiln and is connected with the heat-radiating coil through a pipeline to form a loop.

Further, vertically on the platform truck be provided with many breather pipes, crisscross being equipped with the air vent on the breather pipe and selecting to switch on through pipeline and vacuum pump, nitrogen gas source, air conditioning circulating device and steam source, the timber stock is piled up around the breather pipe and is placed.

Further, the trolley upper surface is provided with mounting holes in a rectangular array, and the lower ends of the vent pipes are inserted into the mounting holes.

Furthermore, a track is transversely arranged in the kiln, the trolley is movably erected on the track, and a linear reciprocating driving mechanism for driving the trolley to move is further arranged on the track side.

Compared with the prior art, the invention has the beneficial effects that: on the premise of ensuring the dimensional stability of the wood, the influence of high-temperature carbonization on the color of the wood is reduced; meanwhile, the production cost is reduced, and the method is suitable for mass production.

1. The wood blank is subjected to preheating treatment, heating treatment and deep drying treatment in a protective atmosphere environment, so that the influence of impurity gases such as oxygen on the wood blank treatment process is effectively prevented, and the change of wood color is reduced in the early stage; meanwhile, the wood blank is ensured not to crack and deform due to internal stress in a reasonable temperature rise and time length range, and the qualified rate of the wood blank is improved.

2. The invention carries out microwave heating carbonization on the wood blank in the vacuum environment, and solves the problem of deepening wood color when the wood blank is carbonized at higher temperature.

3. According to the invention, a plurality of vent pipes are vertically arranged on the trolley, vent holes are arranged on the vent pipes in a staggered manner and are selectively communicated with a vacuum pump, a nitrogen source, a cold air circulating device and a steam source through pipelines, wood blanks are stacked around the vent pipes, and after vacuumizing, nitrogen can be rapidly filled into all parts of the wood blanks through the vent holes during filling; the cold air circulating device can also be quickly filled into all parts of the wood blank through the vent holes; the steam source can also be quickly filled into all parts of the wood blank through the vent holes; all radiate from the interior of the wood blank, and compared with the conventional mode of arranging the vent pipe on the furnace wall, the ventilation mode is much more efficient and thorough.

4. The trolley is arranged on the track in a reciprocating manner, and has the main effects that: on one hand, compared with the position change of the microwave carbonization device, the carbonization treatment is carried out on all parts of the wood blank more uniformly, so that the situation of local carbonization is avoided; on the other hand, the air flow on the vent pipe is favorably dispersed in the moving process, and the treatment efficiency is improved.

5. The modified heat treatment process takes oak wood as a processing object, and after the processing, the water content of carbonized wood is 5-10%; the heat shrinkage resistance of wood is: the length direction is less than or equal to 0.2 percent, and the width direction is less than or equal to 1.0 percent; resistance to Wet swelling: the length direction is less than or equal to 0.2 percent, and the width direction is less than or equal to 0.6 percent; the surface has no cracks and no bubbling phenomenon; the strength is uniform, the bending strength is more than or equal to 50MPa along the grain direction, the elastic modulus is more than or equal to 5GPa along the grain direction, and the impact toughness is more than or equal to 240kJ × m^-2The 200 ℃ color difference Delta E is controlled at 16. On the premise of guaranteeing the dimensional stability of the wood, the reduction of the bending strength, the bending elastic modulus and the impact toughness is not obvious, the color difference is not deepened greatly, namely, the color of the wood is obviously improved compared with the color of the wood after the traditional carbonization treatment.

Drawings

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

FIG. 1 is a first page of a modified heat treated oak blank according to an embodiment of the present invention;

FIG. 2 is a second page of a modified heat treated oak blank according to one embodiment of the present invention;

FIG. 3 is a third page of a modified heat treated oak blank according to one embodiment of the present invention;

FIG. 4 is a fourth page of a modified heat treated oak blank according to one embodiment of the present invention;

FIG. 5 is a schematic diagram of a front view of a processing apparatus according to an embodiment of the present invention;

FIG. 6 is a schematic left side view of the kiln of FIG. 5 in accordance with the present invention;

FIG. 7 is a left side view of the cart of FIG. 5 in accordance with the present invention;

fig. 8 is a schematic top view of the cart of fig. 7 according to the present invention.

In the figure: 1. a kiln; 11. a track; 12. a linear reciprocating drive mechanism; 2. a trolley; 21. a breather pipe; 22. a vent hole; 23. mounting holes; 3. a furnace atmosphere heating device; 31. a heat-dissipating coil pipe; 32. a heat conducting oil heating tank; 4. a microwave carbonization device; 41. a microwave source; 42. a slot antenna; 5. a vacuum pump; 6. a nitrogen source; 7. a cold air circulating device; 8. a source of steam; 9. and (7) an exhaust port.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort, shall fall within the protection scope of the present invention.

In a first aspect, an embodiment of the present invention provides a wood modification heat treatment process, in which wood blanks are placed on a trolley at intervals, stacked in multiple layers vertically, and a downward pressure is applied to the top of the trolley to keep the wood blanks stressed to be flat, and then the wood modification heat treatment process sequentially includes the following steps:

s1, nitrogen replacement and preheating treatment: moving the trolley loaded with the wood blank into a kiln, closing the kiln, vacuumizing the kiln, and controlling the pressure at 10^-3Under Mpa; then, protective gas is filled into the furnace until the pressure in the furnace is micro-positive pressure; starting an atmosphere heating device in the furnace for preheating, wherein the temperature is 30-50 ℃;

s4, vacuum microwave carbonization: closing the furnace atmosphere heating device and the exhaust port, and vacuumizing the furnace, wherein the vacuum degree is kept at 0.5 multiplied by 10^-2~5×10^-2Mpa; starting a microwave carbonization device, wherein the carbonization treatment temperature is 160-200 ℃, and the temperature rise speed is controlled to be 5-10 DEG CThe oxygen content is 0.1-1%, and the treatment time is 5-10 h;

In this embodiment, the moisture content of the wood blank after the S3 treatment is preferably reduced to less than 1%.

In this embodiment, preferably, the micro-positive pressure is 200 to 400PA higher than atmospheric pressure.

In this embodiment, preferably, the circulating air is introduced into the kiln.

In this embodiment, preferably, the protective gas is nitrogen.

The first embodiment is as follows:

taking an oak wood board as an example of wood blank, carrying out modification heat treatment:

a wood modification heat treatment process comprises the steps of airing wood blanks until the water content is 10% -12%, placing the wood blanks on a trolley at intervals, vertically stacking the wood blanks into a plurality of layers, applying downward pressure to the tops of the wood blanks to enable the wood blanks to be stressed and kept flat, and sequentially carrying out the following treatment steps:

s1, nitrogen replacement and preheating treatment: moving the trolley loaded with the wood blank into a kiln, closing the kiln, vacuumizing the kiln, and controlling the pressure at 10^-3Under Mpa; then, filling protective gas, nitrogen is selected, and the pressure in the furnace is micro-positive pressure; starting an atmosphere heating device in the furnace to preheat at 40 ℃, and introducing circulating air into the furnace; wherein the micro-positive pressure is 300Pa higher than the atmospheric pressure;

s2, temperature rising treatment: heating to 65 ℃, controlling the heating speed at 6 ℃/h, controlling the humidity at 75%, controlling the oxygen content at 1%, controlling the treatment time at 6h, opening an exhaust port of the kiln, keeping the micro-positive pressure in the kiln, and introducing circulating air into the kiln;

s3, deep drying treatment: the drying treatment temperature in the furnace is raised to 125 ℃, the temperature raising speed is controlled to be 4 ℃/h, the oxygen content is controlled to be 0.5 percent, the treatment time is 15h, the micro-positive pressure in the furnace is kept, and circulating air is introduced into the kiln; the water content after treatment is reduced to below 1 percent;

s4, vacuum microwave carbonization: closing the furnace atmosphere heating device and the exhaust port, and vacuumizing the furnace, wherein the vacuum degree is maintained at 3 x 10^-2Mpa is about; starting a microwave carbonization device, controlling the carbonization treatment temperature to be 180 ℃, the temperature rise speed to be 7 ℃/h, the oxygen content to be 0.5 percent and the treatment time to be 7 h;

s5, slow cooling treatment: closing the microwave carbonization device, introducing protective gas into the kiln until the pressure is micro-positive pressure, wherein the protective gas is nitrogen, the slow cooling treatment temperature is 125 ℃, the cooling speed is controlled at 7 ℃/h, and circulating air is introduced into the kiln;

s6, quick cooling treatment: starting a cold air circulating device to reduce the treatment temperature in the kiln to 80 ℃, and introducing circulating air into the kiln;

s7, rewetting treatment: and (3) introducing steam into the kiln, controlling the treatment temperature in the kiln at 50 ℃ and the humidity at 75%, introducing circulating air into the kiln, and discharging the wood blank after the water content is controlled at 8%.

The surface has no cracks and no bubbling phenomenon, and the detection indexes are shown in the following table 1.

Oak wood testing reports for this implementation are presented in FIGS. 1-4.

Example two:

s1, nitrogen replacement and preheating treatment: moving the trolley loaded with the wood blank into the kiln, closing the kilnVacuuming the container, and controlling the pressure at 10^-3Under Mpa; then, filling protective gas, nitrogen is selected, and the pressure in the furnace is micro-positive pressure; starting an atmosphere heating device in the furnace to preheat, wherein the temperature is 30 ℃, and circulating air is introduced into the furnace; wherein the micro-positive pressure is 200Pa higher than the atmospheric pressure;

s2, temperature rising treatment: heating to 30 ℃, controlling the heating speed at 3 ℃/h, controlling the humidity at 50%, controlling the oxygen content at 0.1%, treating for 3h, opening an exhaust port of the kiln, keeping the micro-positive pressure in the kiln, and introducing circulating air into the kiln;

s3, deep drying treatment: the drying treatment temperature in the furnace is raised to 100 ℃, the temperature raising speed is controlled to be 3 ℃/h, the oxygen content is controlled to be 0.1 percent, the treatment time is 5h, the micro-positive pressure in the furnace is kept, and circulating air is introduced into the kiln; the water content after treatment is reduced to below 1 percent;

s4, vacuum microwave carbonization: closing the furnace atmosphere heating device and the exhaust port, and vacuumizing the furnace, wherein the vacuum degree is kept at 0.5 multiplied by 10^-2Mpa is about; starting a microwave carbonization device, controlling the carbonization treatment temperature to be 160 ℃, the temperature rise speed to be 5 ℃/h, the oxygen content to be 0.1 percent and the treatment time to be 5 h;

s5, slow cooling treatment: closing the microwave carbonization device, introducing protective gas into the kiln until the pressure is micro-positive pressure, wherein the protective gas is nitrogen, the slow cooling treatment temperature is 120 ℃, the cooling speed is controlled at 5 ℃/h, and circulating air is introduced into the kiln;

s6, quick cooling treatment: starting a cold air circulating device to reduce the treatment temperature in the kiln to 60 ℃, and introducing circulating air into the kiln;

s7, rewetting treatment: and (3) introducing steam into the kiln, controlling the treatment temperature in the kiln at 40 ℃ and the humidity at 50%, introducing circulating air into the kiln, and discharging the wood blank after the water content is controlled at 6%.

Example three:

s1, nitrogen replacement and preheating treatment: moving the trolley loaded with the wood blank into a kiln, closing the kiln, vacuumizing the kiln, and controlling the pressure at 10^-3Under Mpa; then, filling protective gas, nitrogen is selected, and the pressure in the furnace is micro-positive pressure; starting an atmosphere heating device in the furnace to preheat at the temperature of 50 ℃, and introducing circulating air into the furnace; wherein the micro-positive pressure is 400Pa higher than the atmospheric pressure;

s2, temperature rising treatment: heating to 100 ℃, controlling the heating speed at 10 ℃/h, controlling the humidity at 100%, controlling the oxygen content at 2%, controlling the treatment time at 10h, opening an exhaust port of the kiln, keeping the micro-positive pressure in the kiln, and introducing circulating air into the kiln;

s3, deep drying treatment: the drying treatment temperature in the furnace is raised to 150 ℃, the temperature raising speed is controlled at 5 ℃/h, the oxygen content is controlled at 1 percent, the treatment time is 25h, the micro-positive pressure in the furnace is kept, and circulating air is introduced into the furnace; the water content after treatment is reduced to below 1 percent;

s4, vacuum microwave carbonization: closing the furnace atmosphere heating device and the exhaust port, and vacuumizing the furnace, wherein the vacuum degree is kept at 5 multiplied by 10^-2Mpa is about; starting a microwave carbonization device, controlling the carbonization treatment temperature to be 200 ℃, controlling the temperature rise speed to be 10 ℃/h, controlling the oxygen content to be 1% and controlling the treatment time to be 10 h;

s5, slow cooling treatment: closing the microwave carbonization device, introducing protective gas into the kiln until the pressure is micro-positive pressure, wherein the protective gas is nitrogen, the slow cooling treatment temperature is 130 ℃, the cooling speed is controlled at 10 ℃/h, and circulating air is introduced into the kiln;

s6, quick cooling treatment: starting a cold air circulating device to reduce the treatment temperature in the kiln to 100 ℃, and introducing circulating air into the kiln;

s7, rewetting treatment: and (3) introducing steam into the kiln, controlling the treatment temperature in the kiln at 60 ℃ and the humidity at 100%, introducing circulating air into the kiln, and discharging the wood blank after the water content is controlled at 10%.

The surface has no cracks and no bubbling phenomenon, and the detection indexes are shown in the following table 1:

watch (A)

Detection index of oak board after modification heat treatment

According to the modification heat treatment process, the oak board is taken as a processing object, and after the processing of the modification heat treatment process, the water content of the carbonized wood in the first to third embodiments is 5% -10% as can be seen from the table; the heat shrinkage resistance of wood is: the length direction is less than or equal to 0.2 percent, and the width direction is less than or equal to 1.5 percent; resistance to Wet swelling: the length direction is less than or equal to 0.2 percent, and the width direction is less than or equal to 0.8 percent; the surface has no cracks and no bubbling phenomenon; the strength is uniform, the bending static bending strength is more than or equal to 50MPa along the grain direction, the elastic modulus is more than or equal to 5GPa along the grain direction, and the impact toughness is more than or equal to 240KJ/m^-2And the color difference delta E at 200 ℃ is controlled within 16.

In a second aspect, referring to fig. 5-8, the present invention further provides a processing apparatus for the wood modification heat treatment process, comprising: the device comprises a kiln 1, a trolley 2, an in-furnace atmosphere heating device 3, a microwave carbonization device 4, a vacuum pump 5, a nitrogen source 6, a cold air circulating device 7, a steam source 8 and an exhaust port 9, wherein the vacuum pump 5, the nitrogen source 6, the cold air circulating device 7, the steam source 8 and the exhaust port are communicated with pipelines in the kiln 1; the pipeline of the exhaust port 9 is provided with a valve and a water seal box, namely the pipeline is inserted under the water surface, when the pressure in the furnace is slightly positive, moisture discharged from the furnace can be discharged into the water seal box and collected, and the water seal box can only flow back a small section to the pipe to buffer the variation pressure difference in the furnace;

the microwave carbonization device 4 includes: the microwave oven comprises a microwave source 41 and a crack antenna 42 connected with the microwave source, wherein the crack antenna 42 extends into the kiln 1, a plurality of trolleys 2 are uniformly distributed at intervals in the kiln 1, and gaps on the crack antenna 42 face the trolleys 2.

When the heat insulation material kiln is used specifically, the heat insulation material is arranged in the kiln 1, the heat insulation material can be cylindrical, the axis of the heat insulation material is horizontally arranged, a furnace door is arranged on one side of the heat insulation material, wood blanks are arranged on a first layer on the trolley 2 at intervals along a first transverse direction, wood blanks are arranged on a second layer on the trolley 2 at intervals along a second transverse direction perpendicular to the first transverse direction, the third layer is arranged upwards in the same way as the first layer, the fourth layer is arranged in the same way as the second layer, and the rest is done by analogy with … …, and the wood blanks are arranged in a grid shape; under the environment with medium gas, the furnace atmosphere heating device 3 is used for heating the atmosphere in the furnace, and the microwave carbonization device 4 is used for microwave heating carbonization of the wood blank under the vacuum state; vacuum pump 5, nitrogen source 6, cold air circulating device 7, steam source 8, gas vent 9 communicate with each other through pipeline and stove in, this equipment integrated level is high, is convenient for carry out heat treatment operation to timber.

In this embodiment, preferably, the furnace atmosphere heating device 3 includes: the heat-conducting oil heating device comprises a heat-radiating coil 31 arranged on the inner side wall of the kiln 1 and a heat-conducting oil heating tank 32 positioned outside, wherein the heat-conducting oil heating tank 32 is connected with the heat-radiating coil 31 through a pipeline to form a loop. A high temperature resistant fan can be arranged on the furnace wall at one side of the heat dissipation coil 31, and the fan blows the heat of the heat dissipation coil 31 to the trolley 2.

In this embodiment, preferably, a plurality of vent pipes 21 are vertically arranged on the trolley 2, vent holes 22 are alternately arranged on the vent pipes 21 and selectively communicated with the vacuum pump 5, the nitrogen source 6, the cold air circulating device 7 and the steam source 8 through pipelines, and the wood blanks are stacked around the vent pipes 21. Namely, the vent pipe 21 is positioned at the mesh of the latticed wood blank, and after vacuum pumping, when nitrogen is filled, the nitrogen can be quickly filled into all parts of the wood blank through the vent hole 22; the cold air circulating device 7 can also be quickly filled into all parts of the wood blank through the vent holes 22; the steam source 8 can also be quickly filled into all parts of the wood blank through the vent holes 22; the wood is radiated from the interior of the wood blank, and compared with the conventional mode of arranging the vent pipe on the furnace wall, the ventilation mode in the embodiment is much more efficient and thorough.

In this embodiment, preferably, the upper surface of the trolley 2 is provided with mounting holes 23 in a rectangular array, and the lower end of the air pipe 21 is inserted into the mounting holes 23. The lower end of the vent pipe 21 can be installed in the installation hole 23 through threads, so that the interference caused by the vent pipe 21 is avoided when wood blanks are assembled and disassembled conveniently. The inside air flue that communicates with each other with mounting hole 23 that is equipped with of platform truck 2 gathers in the kneck of its portion, and this interface can be through the intake pipe detachable connection on hose and the kiln 1.

In this embodiment, preferably, a rail 11 is transversely arranged in the kiln 1, the trolley 2 is movably erected on the rail 11, and a linear reciprocating driving mechanism 12 for driving the trolley 2 to move is further arranged on the side of the rail 11. The linear reciprocating drive mechanism 12 may include: the rack is arranged at the bottom of the trolley 2 along the extension direction of the track, the gear is rotatably arranged below the inner wall of the furnace, the axis of the gear is horizontal, the gear penetrates out of the furnace through a transmission shaft and is in transmission connection with a speed reducer, and when the gear rotates forwards and backwards and is matched with the rack, the trolley 2 can reciprocate on the track 11; the main effect of the action is that on one hand, compared with the position change of the microwave carbonization device 4, the carbonization treatment is carried out on all parts of the wood blank, so that the carbonization is more uniform, and the situation of local carbonization is avoided; on the other hand, the air flow on the vent pipe 21 is facilitated to be diffused during the moving process.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

Claims

1. A wood modification heat treatment process is characterized in that wood blanks are placed on a trolley at intervals, a plurality of layers of wood blanks are vertically stacked, downward pressure is applied to the tops of the wood blanks to enable the wood blanks to be stressed and kept flat, and then the wood modification heat treatment process sequentially comprises the following processing steps:

2. The wood-modifying heat treatment process of claim 1, wherein the moisture content of the wood stock after the S3 treatment is reduced to less than 1%.

3. The wood modification heat treatment process according to claim 1, wherein the micro positive pressure is 200 to 400Pa above atmospheric pressure.

4. The wood modification heat treatment process of claim 1, wherein circulating air is introduced into the kiln.

5. The wood-modifying heat treatment process of claim 1, wherein the shielding gas is nitrogen.

6. The treatment equipment of a wood modification heat treatment process according to any one of claims 1 to 5, comprising: the device comprises a kiln (1), a trolley (2), a furnace atmosphere heating device (3), a microwave carbonization device (4), a vacuum pump (5), a nitrogen source (6), a cold air circulating device (7), a steam source (8) and an exhaust port (9), wherein the vacuum pump, the nitrogen source, the cold air circulating device (7), the steam source and the exhaust port are communicated with a pipeline in the kiln (1);

the microwave carbonization device (4) comprises: the microwave oven comprises a microwave source (41) and a crack antenna (42) connected with the microwave source, wherein the crack antenna (42) extends into the oven (1), a plurality of trolleys (2) are uniformly distributed at intervals on two sides of the oven (1), and gaps on the crack antenna (42) face the trolleys (2).

7. Treatment plant according to claim 6, characterized in that said furnace atmosphere heating means (3) comprise: the heat-conducting oil heating device comprises a heat-radiating coil pipe (31) arranged on the inner side wall of the kiln (1) and a heat-conducting oil heating tank (32) located outside, wherein the heat-conducting oil heating tank (32) is connected with the heat-radiating coil pipe (31) through a pipeline to form a loop.

8. The processing apparatus according to claim 6, wherein a plurality of air pipes (21) are vertically arranged on the trolley (2), air holes (22) are alternately arranged on the air pipes (21) and are selectively communicated with the vacuum pump (5), the nitrogen source (6), the cold air circulating device (7) and the steam source (8) through pipelines, and the wood blanks are stacked around the air pipes (21).

9. The processing apparatus according to claim 8, wherein the trolley (2) is provided with mounting holes (23) on the upper surface in a rectangular array, and the lower ends of the vent pipes (21) are inserted into the mounting holes (23).

10. The processing equipment according to any one of claims 6 to 9, wherein a rail (11) is transversely arranged in the kiln (1), the trolley (2) is movably erected on the rail (11), and a linear reciprocating driving mechanism (12) for driving the trolley (2) to move is further arranged on the side of the rail (11).