阅读说明：本技术 一种木材软化方法 (Wood softening method ) 是由 董晓娜 杨众养 陈飞飞 林玲 黄川腾 张一民 刘斌 于 2021-07-08 设计创作，主要内容包括：本发明公开了一种木材软化方法,涉及木材处理技术领域,其技术方案要点是：包括以下步骤：S1、构建木材软化数据模型；S2、获取木材软化数据模型的多元回归方程,将多元回归方程和木材软化数据模型植入至木材软化处理工艺设备的控制单元中；S3、对木材进行水热软化处理；S4、将水热软化木材进行微波软化处理；S5、对水热-微波联合软化处理木材的表面进行干燥,即获得软化木材。本方法能够针对不同气干密度的不同木材进行对应的软化处理条件及软化处理参数的调控,且能够克服单一采用水热处理的时间局限性,同时确保木材软化处理的质量,避免木材经过化学试剂软化对木材结构和内部组织的损坏,减小环境污染,该方法便于用于木材切片标本的制作。(The invention discloses a wood softening method, which relates to the technical field of wood treatment and has the technical scheme that: the method comprises the following steps: s1, constructing a wood softening data model; s2, acquiring a multiple regression equation of the wood softening data model, and implanting the multiple regression equation and the wood softening data model into a control unit of the wood softening processing equipment; s3, carrying out hydrothermal softening treatment on the wood; s4, performing microwave softening treatment on the hydrothermally softened wood; and S5, drying the surface of the wood subjected to the hydrothermal-microwave combined softening treatment to obtain the softened wood. The method can adjust and control corresponding softening treatment conditions and softening treatment parameters aiming at different woods with different air-dry densities, can overcome the time limitation of single hydrothermal treatment, simultaneously ensures the quality of wood softening treatment, avoids the damage of the wood structure and internal tissues caused by the softening of the wood by chemical reagents, reduces the environmental pollution, and is convenient for manufacturing wood slice specimens.)

1. A wood softening method is characterized in that: the method specifically comprises the following steps:

s1, constructing a wood softening data model, and constructing the wood softening data model suitable for processing wood with different lignin contents and different air-dry densities at different hydrothermal temperatures for different time and different microwave power for different time, wherein the wood softening data model is as follows: x ═ f (a, b, c, d, e), where X represents the lignin content of the wood, a represents the air-dry density of the wood, b represents the hydrothermal treatment temperature, c represents the hydrothermal treatment time, d represents the microwave power of the microwave treatment, and e represents the microwave treatment time;

s2, acquiring a multiple regression equation of the wood softening data model according to the constructed wood softening data model, and implanting the multiple regression equation and the wood softening data model in the step S1 into a control unit of the wood softening processing equipment;

s3, softening the wood, measuring the air-dry density of the wood to be softened, and carrying out hydrothermal softening treatment on the wood through wood softening treatment process equipment according to the measured air-dry density of the wood to obtain the hydrothermal softened wood;

s4, performing microwave softening treatment, namely wrapping the hydro-thermally softened wood obtained in the step S3 by a wood waterproof film, and performing microwave softening treatment on the wrapped wood to obtain hydro-thermally and microwave combined softened wood;

and S5, drying the surface of the wood subjected to the hydrothermal-microwave combined softening treatment obtained in the step S4 to obtain softened wood.

2. A wood softening process according to claim 1, wherein: the specific method for obtaining the multiple regression equation of the wood softening data model in step S2 is as follows:

A. selecting different types of woods with different air-dry densities as test pieces, and grouping the different types of woods with different air-dry densities according to a hydrothermal-microwave combined softening treatment process flow to perform a hydrothermal-microwave combined softening treatment orthogonal test;

B. and (3) taking the average value of the experimental data of each group of test pieces in the step A as each group of test results, and then applying graphpadinstat to analyze to obtain a multiple regression equation of which X is f (a, b, c, d, e).

3. A wood softening process according to claim 1, wherein: the hydrothermal temperature and the hydrothermal softening time of the hydrothermal softening treatment in step S3 are automatically controlled by the control unit of the wood softening treatment process equipment according to the wood softening data model and the multiple regression equation thereof.

4. A wood softening process according to claim 1, wherein: the microwave power and the microwave treatment time for the microwave softening treatment in step S4 are automatically controlled by the control unit of the wood softening treatment process equipment according to the wood softening data model and its multiple regression equation.

5. A wood softening process according to claim 1, wherein: and step S5, drying the surface of the wood subjected to the hydrothermal-microwave combined softening treatment by adopting a cold air quick drying mode.

6. Use of a method of softening wood according to any one of claims 1 to 5, characterized in that: and (4) taking the obtained softened wood, and slicing the softened wood for manufacturing a wood slice specimen.

Technical Field

The invention relates to the technical field of wood treatment, in particular to a wood softening method.

Background

The wood is one of four major materials recognized in the world, has the advantages of being renewable, free of pollution, low in cost, high in strength-to-weight ratio and the like, can be used as products such as boards, furniture, plywood and the like, can be used as raw materials of paper making and chemical fiber industries, and plays an important role in modern construction. The wood identification has important significance for correctly recognizing wood, understanding wood characteristics and reasonably utilizing wood.

Wood identification is based on the classification of botany and based on the anatomical features of the interior of the wood, wood is identified and classified. Wood identification process, i.e. wood species identification process. The wood identification method is mainly divided into macroscopic identification and microscopic identification. The research institute and the authority identification institution mostly adopt a method of combining macroscopic recognition and microscopic recognition, and the accuracy and the scientificity of wood recognition can be ensured. To accurately identify wood, particularly in the case of a wide variety of imported tropical wood species (including many poorly known, poorly utilized tree species), it is necessary to have a properly named wood specimen, generally from a specimen room in a research institute and an academic institution or collected by the institute, but all of them must be properly named by a botanist or a tree classificator and have a Latin name attached thereto. The general wood specimen is provided with a corresponding tree leaf specimen and a permanent optical section, and each section comprises three sections of transverse section, radial section and chord section of the wood. The wood specimen and the section are valuable materials for direct comparison in wood identification. The main process for manufacturing the wood slices comprises the following 4 steps:

1. material taking and sample preparation: permanent slicing of wood generally requires three faces, namely a cross-cut face, a diametral face and a chord-line face. When the material is taken, three surfaces are as positive as possible and are square. The material can be determined according to the material, generally not less than 1cm multiplied by 2cm, the transverse plane requires at least one complete annual ring, and the limit of the annual ring is parallel to the long edge.

2. Softening: at present, the methods for softening wood mainly include physical methods and chemical methods. Among them, the physical method is generally a hydrothermal method, that is, heating the wood by external heating to soften the wood. Usually a hot water soaking method, a sawn wood sample is soaked in boiling water at 100 ℃ until the sample has a moderate hardness. If the wood hardness is relatively large, it may take one month or more. The method is environment-friendly and low in cost, but is labor-consuming and time-consuming and low in efficiency. But the method does not damage the wood structure and is adopted in more laboratories. The chemical softener has various formulas and different effects, but the reagent is toxic, the structure of the wood can be damaged, and the laboratory use is less.

3. Slicing: the softened wood samples were mounted on a microtome for sectioning.

4. Dyeing: after the cut wood slices are dyed by safranin, different gradient alcohol concentrations are dehydrated, and xylene or an environment-friendly dewaxing agent is transparent. Sealing the treated neutral resin slices, and drying in the shade or at low temperature.

In the process of manufacturing the wood microtome, wood softening is always the most important link, and directly influences the time required by manufacturing the wood microtome, the microtome quality and the final identification result. At present, the most commonly adopted softening mode in the process of manufacturing the wood slices is conventional water boiling softening, and the sawn wood samples are placed in boiling water of 100 ℃ for continuous cooking until the hardness of the samples is moderate. When the hydrothermal treatment is used alone, water hardly enters the crystallization zone of the wood even under heating conditions, and the purpose of sufficient softening is achieved. Therefore, the hydrothermal treatment alone is not ideal for softening wood, the time required for softening the wood is too long, and the long-time soaking causes the defects of breakage, shrinkage and the like of the wood.

Therefore, the present invention is directed to a method of softening wood to solve the above problems.

Disclosure of Invention

The invention aims to solve the defects that the softening time is too long, and the breakage, shrinkage and the like are easy to occur when the hydrothermal treatment method is independently adopted to soften the wood in the prior art, and provides a wood softening method.

The method is characterized in that a wood softening data model is constructed, a multiple regression equation of the model is obtained, corresponding softening treatment conditions and softening treatment parameters are adjusted and controlled according to different woods with different air-dry densities, and the method is used for softening the wood in a mode of combining hydrothermal treatment and microwave treatment, so that the limitation of single hydrothermal treatment can be overcome, the quality of wood softening treatment is ensured, the defects of breakage, shrinkage and the like after softening treatment can be avoided, the softening quality of the wood is improved, and the method is convenient for manufacturing wood slice specimens.

The technical purpose of the invention is realized by the following technical scheme: a wood softening method specifically comprises the following steps:

s1, constructing a wood softening data model, and constructing the wood softening data model suitable for processing wood with different lignin contents and different air-dry densities at different hydrothermal temperatures for different time and different microwave power for different time, wherein the wood softening data model is as follows: x ═ f (a, b, c, d, e), where X represents the lignin content of the wood, a represents the air-dry density of the wood, b represents the hydrothermal treatment temperature, c represents the hydrothermal treatment time, d represents the microwave power of the microwave treatment, and e represents the microwave treatment time;

s2, acquiring a multiple regression equation of the wood softening data model according to the constructed wood softening data model, and implanting the multiple regression equation and the wood softening data model in the step S1 into a control unit of the wood softening processing equipment;

s3, softening the wood, measuring the air-dry density of the wood to be softened, and carrying out hydrothermal softening treatment on the wood through wood softening treatment process equipment according to the measured air-dry density of the wood to obtain the hydrothermal softened wood;

s4, performing microwave softening treatment, namely wrapping the hydro-thermally softened wood obtained in the step S3 by a wood waterproof film, and performing microwave softening treatment on the wrapped wood to obtain hydro-thermally and microwave combined softened wood;

and S5, drying the surface of the wood subjected to the hydrothermal-microwave combined softening treatment obtained in the step S4 to obtain softened wood.

Further, the specific method for obtaining the multiple regression equation of the wood softening data model in step S2 is as follows:

A. selecting different types of woods with different air-dry densities as test pieces, and grouping the different types of woods with different air-dry densities according to a hydrothermal-microwave combined softening treatment process flow to perform a hydrothermal-microwave combined softening treatment orthogonal test;

B. and (3) taking the average value of the experimental data of each group of test pieces in the step A as each group of test results, and then applying graphpadinstat to analyze to obtain a multiple regression equation of which X is f (a, b, c, d, e).

Further, the hydrothermal temperature and the hydrothermal softening time of the hydrothermal softening treatment in step S3 are automatically controlled by the control unit of the wood softening treatment process equipment according to the wood softening data model and the multiple regression equation thereof.

Further, the microwave power and the microwave treatment time for the microwave softening treatment in step S4 are automatically controlled by the control unit of the wood softening treatment process equipment according to the wood softening data model and its multiple regression equation.

Further, in step S5, the surface of the wood treated by the hydrothermal-microwave combined softening process is dried by using a cold air rapid drying method.

The invention also provides an application of the wood softening method: and (4) taking the obtained softened wood, and slicing the softened wood for manufacturing a wood slice specimen.

In conclusion, the invention has the following beneficial effects:

1. according to the method, the wood softening data model is constructed and the multiple regression equation of the wood softening data model is obtained, so that the corresponding softening treatment conditions and softening treatment parameters can be conveniently regulated and controlled for different woods with different air dry densities in the process of softening the wood, the regulation and control precision is high, and the efficiency and the quality of softening the wood can be conveniently improved;

2. the method combines the hydrothermal treatment and the microwave treatment, and the condition parameters of the hydrothermal treatment and the microwave treatment can be quantitatively regulated and controlled under the optimal complementary condition, so that the limitation of singly adopting the hydrothermal treatment can be overcome, the quality of the wood softening treatment is ensured, the yield of the wood softening treatment is improved, and the method is convenient for manufacturing the wood slice specimen.

Drawings

Fig. 1 is a flow chart in an embodiment of the present invention.

Detailed Description

The present invention is described in further detail below with reference to fig. 1.

Example (b): a method of softening wood, as shown in fig. 1, specifically comprising the steps of:

s1, constructing a wood softening data model, and constructing the wood softening data model suitable for processing wood with different lignin contents and different air-dry densities at different hydrothermal temperatures for different time and different microwave power for different time, wherein the wood softening data model is as follows: x ═ f (a, b, c, d, e), where X represents the lignin content of the wood, a represents the air-dry density of the wood, b represents the hydrothermal treatment temperature, c represents the hydrothermal treatment time, d represents the microwave power of the microwave treatment, and e represents the microwave treatment time.

S2, obtaining a multiple regression equation of the wood softening data model according to the constructed wood softening data model, and implanting the multiple regression equation and the wood softening data model in the step S1 into a control unit of the wood softening treatment process equipment.

And S3, softening the wood, measuring the air-dry density of the wood to be softened, and carrying out hydrothermal softening treatment on the wood through wood softening treatment process equipment according to the measured air-dry density of the wood to obtain the hydrothermal softened wood.

And S4, performing microwave softening treatment, namely wrapping the hydrothermal softened wood obtained in the step S3 by a wood waterproof film, and performing microwave softening treatment on the wood to obtain the hydrothermal-microwave combined softening treated wood.

And S5, drying the surface of the wood subjected to the hydrothermal-microwave combined softening treatment obtained in the step S4 to obtain softened wood.

The specific method for obtaining the multiple regression equation of the wood softening data model in step S2 is as follows:

A. selecting different types of timbers with different air-dry densities as test pieces, and grouping the timbers with different types and different air-dry densities according to the hydrothermal-microwave combined softening treatment process flow to perform an orthogonal test of hydrothermal-microwave combined softening treatment.

B. And (3) taking the average value of the experimental data of each group of test pieces in the step A as each group of test results, and then applying graphpadinstat to analyze to obtain a multiple regression equation of which X is f (a, b, c, d, e).

In step S3, the hydrothermal temperature and the hydrothermal softening time of the hydrothermal softening treatment are automatically controlled by the control unit of the wood softening treatment process equipment according to the wood softening data model and the multiple regression equation thereof.

In step S4, the microwave power and the microwave processing time for the microwave softening processing are automatically controlled by the control unit of the wood softening processing equipment according to the wood softening data model and the multiple regression equation thereof.

In step S5, the surface of the wood softened by the hydrothermal-microwave combination is dried by using a cold air rapid blow drying method.

In this embodiment, according to the process flow of the hydrothermal-microwave combined softening treatment, the orthogonal tests of performing the hydrothermal-microwave combined softening treatment on different types and different air-dry densities of wood in groups are as follows:

1) selecting multiple species with certain density gradient as test material, such as radix Aristolochice (air-dried dense)The degree is about 0.4g/cm³) And artificial forest teak (air dry density about 0.5 g/cm)³) Betula alnoides (air dry density about 0.6 g/cm)³) And natural forest teak (air dry density about 0.7 g/cm)³) And Eucalyptus citriodora (air-dried density of about 0.80 g/cm)³)。

2) And carrying out hydrothermal treatment on the wood sample subjected to the vacuumizing treatment, and strictly controlling the hydrothermal temperature and the hydrothermal treatment time. And (3) quickly taking out the test piece after the hydrothermal treatment and wrapping the test piece with a preservative film to prevent the moisture in the wood from being seriously lost due to the irradiation of microwaves. In order to prevent the treated wood from recovering rigidity again due to the reduction of temperature, the treated test piece needs to be measured for lignin content (namely radial compression displacement) at the fastest speed, and orthogonal experimental parameters and measurement results are shown in the following table 1:

TABLE 1

According to the test data in the table 1, the test data is processed by using function drawing software oringin8.5 to obtain a multiple regression equation of the lignin content X with respect to different densities, different hydrothermal temperatures and times, and different microwave powers and times:

x34.442-46.382 a +0.08497 b +0.02827 c +0.01856 d +0.0302 e, determining the coefficient R²＝0.9015。

In the embodiment of the invention, the wood softening data model is constructed and the multiple regression equation of the wood softening data model is obtained, and the corresponding softening treatment conditions and the softening treatment parameters are regulated and controlled aiming at different woods with different air-dry densities, and the method adopts a mode of combining hydrothermal treatment and microwave treatment to soften the wood, so that the limitation of singly adopting hydrothermal treatment can be overcome, the quality of wood softening treatment is ensured, the damage of the wood structure and the internal tissue caused by softening the wood by a chemical reagent is avoided, the defects of breakage, shrinkage and the like after softening treatment are avoided, and the environmental pollution is reduced; in addition, the method of the invention is convenient for manufacturing the wood slice specimen.

The present embodiment is only for explaining the present invention, and it is not limited to the present invention, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present invention.