Thermal modification method for logs or thick square lumber

A technology of thermal modification and log, which is applied in the field of thermal modification of log or thick square timber, which can solve the problems such as the decline of mechanical properties of heat-treated wood, improve the dimensional stability and biological resistance of wood, prevent water absorption and penetration, Operational Security Effects

Active Publication Date: 2017-05-31
HENAN IINKHIGH OVERALL FURNITURE CO LTD
View PDF3 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] However, the degradation of carbohydrates also leads to the decline of the main mechanical properties of heat-treated wood, among which the impact toughness and flexural strength are most obviously affected by heat treatment, and the decline can reach nearly 50%, which limits the application of traditional heat-treated wood to Non-structural materials or products with small loads

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Thermal modification method for logs or thick square lumber

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0027] The thermal modification method of the wood of the present embodiment, the concrete steps are:

[0028] (1) Preparation stage: put the wood with a moisture content of 7~8% into the treatment kiln;

[0029] (2) Heat treatment: nitrogen gas was introduced into the treatment kiln, and the temperature in the kiln was raised to 80°C within 1 hour, then the temperature was raised from 80°C to 145°C at a rate of 15°C / h, and then increased from 145°C to 25°C / h. The rate of h was heated to 170 °C;

[0030] (3) Cooling and cooling: Turn off the heat source, make the temperature in the kiln drop at a rate of 35℃ / h, discharge the nitrogen in the kiln out of the kiln, and at the same time introduce nitrogen gas at room temperature into the kiln, after the temperature in the kiln drops to 100℃, add it to the kiln. Air is introduced into the kiln, and water is sprayed into the kiln at the same time.

Embodiment 2

[0032] The thermal modification method of the wood of the present embodiment, the concrete steps are:

[0033] (1) Preparation stage: put the wood with a moisture content of 7~8% into the treatment kiln;

[0034] (2) Heating treatment: nitrogen gas was introduced into the treatment kiln, the temperature in the kiln was raised to 90°C within 1 hour, then the temperature was raised from 90°C to 150°C at a rate of 13°C / h, and then increased from 150°C to 23°C / h. The rate of h was heated to 160 °C;

[0035] (3) Cooling and cooling: Turn off the heat source, make the temperature in the kiln drop at a rate of 30°C / h, discharge the nitrogen in the kiln out of the kiln, and at the same time inject nitrogen at room temperature into the kiln, after the temperature in the kiln drops to 100°C, add it to the kiln. Air is introduced into the kiln, and water is sprayed into the kiln at the same time.

Embodiment 3

[0037] The thermal modification method of the wood of the present embodiment, the concrete steps are:

[0038] (1) Preparation stage: Put Douglas fir wood with a moisture content of 7~8% into the treatment kiln;

[0039] (2) Heating treatment: nitrogen is introduced into the treatment kiln, the temperature in the kiln is raised to 100°C within 1 hour, and then the temperature is raised from 100°C to 140°C at a rate of 10°C / h, and then from 140°C at a rate of 20°C / h. The rate of h was heated to 180 °C;

[0040] (3) Cooling and cooling: Turn off the heat source, make the temperature in the kiln drop at a rate of 40 °C / h, discharge the nitrogen in the kiln out of the kiln within 10 minutes, and at the same time introduce normal temperature nitrogen into the kiln, and the temperature in the kiln drops to 100 °C , the air is introduced into the kiln, and the water is sprayed into the kiln at the same time.

[0041] In order to verify the effect of the heat treatment method of the...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention provides a thermal modifying method suitable for logs or thick lumbers. The method comprises the following wood treatment steps: woods with a water content of 7-8% are put in a treatment kiln; nitrogen is filled in the treatment kiln; the temperature in the kiln rises to 100 DEG C within 1 hour, rises to 140-150 DEG C at a speed of 10-15 DEG C / h, and rises to 160-180 DEG C at a speed of 20-25 DEG C / h; a heat source is closed; the nitrogen in the kiln is discharged out of the kiln; meanwhile, normal-temperature nitrogen is filled in the kiln, so that the temperature in the kiln is reduced at a speed of 30-40 DEG C / h; after the temperature in the kiln is reduced to 100 DEG C, air is introduced in the kiln; and meanwhile, atomized water is sprayed into the kiln. The heat treatment is performed under normal-pressure drying condition, so that the operation is safe, the treatment environment is not corroded, the treatment period is obviously shortened, and the production efficiency is high; and the treated woods have double-layer structures, so that the surface layer stability and durability are improved, the internal wood chemical structures are not changed, and the total wood mechanical strength is kept basically invariable.

Description

technical field [0001] The invention belongs to the field of wood modification, and in particular relates to a thermal modification method suitable for logs or thick square wood. Background technique [0002] Thermal modification of wood, also known as wood heat treatment, is a method of heat treating wood in an inert environment around 200°C to adjust the color of the wood and increase its dimensional stability and biological durability. The inert treatment environment is used to avoid excessive degradation of wood in aerobic high temperature environment and to avoid fire hazards. Commonly used inert media include water vapor, nitrogen, vegetable oil and water. [0003] The improved dimensional stability of heat-treated wood is mainly attributed to the partial degradation of carbohydrates, especially hemicelluloses, inside the wood at high temperature. Existing studies have shown that 160 °C is a temperature turning point for wood heat treatment. When the temperature level...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): B27K5/00
CPCB27K5/0085
Inventor 丁涛耿君蔡家斌彭文文胡新军
Owner HENAN IINKHIGH OVERALL FURNITURE CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap