The Method of Improving the Performance of Carbonized Wood by Silica Sol Impregnation Pretreatment

A silica sol and pretreatment technology, applied in wood treatment, impregnated wood, wood treatment details, etc., can solve the problems of dimensional stability, corrosion resistance, weather resistance, flame retardancy, density, mechanical strength, etc. Decrease and other problems, to achieve the effect of improving mechanical strength, inhibiting the reproduction of fungi, and reducing the balance of moisture content

Active Publication Date: 2015-12-09
RUBBER RES INST CHINESE ACADEMY OF TROPICAL AGRI SCI
View PDF8 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] At present, the carbonized wood processed by the existing known technology still has the following disadvantages: 1) After high-temperature carbonization, the wood becomes brittle, its density and mechanical strength decrease, and it may break during production or use; 2) It is treated at a temperature lower than 200 °C The dimensional stability, corrosion resistance and weather resistance of the obtained carbonized wood have not been significantly improved; 3) The flame retardancy of the carbonized wood has not been improved; 4) The carbonized wood is more susceptible to termites than uncarbonized wood
However, the flame retardant performance of carbonized wood produced by resin impregnation pretreatment has not been improved; moreover, some resins (such as urea-formaldehyde resin) have poor thermal stability, and thermal decomposition will occur during wood carbonization; at the same time, the resin During the impregnation process, free formaldehyde is released, which is harmful to human health and causes environmental pollution; in addition, the resin pretreatment technology needs to reduce the moisture content of the wood (less than 15%), so the wood needs to be dried before the resin pretreatment , the production cost increases

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0023] 1) Selection of silica sol: The specifications of the selected silica sol: pH value is 7.20, SiO 2 The content is 35%, the density is 1.20g / cm 3 , the particle size range is 30-50nm.

[0024] 2) Wood impregnation pretreatment: Using vacuum pressure method, put 2.5cm thick rubber wood in the treatment tank, evacuate to -0.09MPa, keep it for 15min, then inject silica sol, after the treatment tank is full, pressurize to 1.0MPa, keep it for 1 hour, release the pressure, return the silica sol to the storage tank, evacuate it again to -0.08MPa, keep it for 15 minutes, release the vacuum, discharge the residual silica sol, and take out the wood;

[0025] 3) Wood drying: Stack and weigh the impregnated rubber wood. After air-drying for 5 days, put it in a periodic forced circulation drying kiln for conventional kiln drying. The drying time is 7 days, and the moisture content of the wood is reduced to 13% out of the kiln;

[0026] 4) Wood carbonization: put the dried rubber w...

Embodiment 2

[0028] 1) Selection of silica sol: The specifications of the selected silica sol: pH value is 6.80, SiO 2 The content is 25%, the density is 1.16g / cm 3 , the particle size range is 10-25nm;

[0029] 2) Wood impregnation pretreatment: use vacuum pressure method, put 3.5cm thick rubber wood in the treatment tank, vacuumize to -0.08MPa, keep for 25min, then inject silica sol, after the treatment tank is filled, pressurize to 1.4MPa, keep it for 1.5h, release the pressure, return the silica sol to the liquid storage tank, evacuate it again to -0.09MPa, keep it for 10min, release the vacuum, discharge the residual silica sol, and take out the wood;

[0030] 3) Drying of wood: Stack and weigh the impregnated rubber wood. After 7 days of air drying, they are placed in a periodic forced circulation drying kiln for conventional kiln drying. The drying time is 9 days, and the moisture content of the wood is reduced to 15% out of the kiln;

[0031] 4) Wood carbonization: put the dried...

Embodiment 3

[0033] 1) Selection of silica sol: The specifications of the selected silica sol: pH value is 7.80, SiO 2 The content is 45%, the density is 1.35g / cm 3 , the particle size range is 55-85nm;

[0034] 2) Wood impregnation pretreatment: use vacuum pressure method, put 5.5cm thick rubber wood in the treatment tank, vacuumize to -0.85MPa, keep for 35min, then inject silica sol, after the treatment tank is filled, pressurize to 1.8MPa, keep it for 1.5h, release the pressure, return the silica sol to the storage tank, evacuate it again to -0.09MPa, keep it for 5min, release the vacuum, discharge the residual silica sol, and take out the wood;

[0035] 3) Wood drying: The impregnated rubber wood is stacked and weighed. After 9 days of air drying, it is placed in a periodic forced circulation drying kiln for conventional kiln drying. The drying time is 13 days, and the moisture content of the wood is reduced to 17% out of the kiln;

[0036] 4) Wood carbonization: put the dried rubbe...

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

PropertyMeasurementUnit
densityaaaaaaaaaa
particle diameteraaaaaaaaaa
Login to view more

Abstract

The invention relates to a method for improving a carbonized wood property by silica sol impregnation pretreatment. The method comprises the following steps of: placing wood in a treatment tank, carrying out the silica sol infusion pretreatment on the wood, and carrying out stacking and air dry on the treated wood; carrying out common kiln drying on the treated wood so as to enable the water content ratio of the wood to be reduced to be 12-18%, and then discharging the dried wood out of a kiln, placing the wood after drying in charring equipment for carrying out hot modification carbonizing treatment; and finally taking out the wood. The method provided by the invention has the advantages that silica sol is adopted to be used as modification liquid so as to carry out the impregnation pretreatment on the wood, the front drying is not needed, the manufacturing cost is low, the mass loss rate of preparative carbonized wood is reduced, and the equilibrium water content is reduced; and the dimensional stability. the density and the mechanical strength are improved, corrosion proof and weather resisting properties are improved, flame retardant and termite proof properties can be improved to a certain degree, and the method has the characteristics of being odorless, innoxious, safe and environment-friendly.

Description

technical field [0001] The invention belongs to the field of wood processing, and relates to a method for thermally modifying and carbonizing wood, in particular to a method for improving the properties of carbonized wood through silica sol impregnation pretreatment. Background technique [0002] Carbonized wood is a wood product with excellent performance, beautiful color and environmental friendliness (Gu Lianbai et al., 2008). It can be widely used in decoration, flooring, furniture and garden landscape, and is favored by consumers. At present, domestic wood carbonization methods mainly use superheated steam or nitrogen as heat transfer medium and protective gas to avoid excessive oxidation degradation or combustion of wood during carbonization, such as CN1868704A, CN101069972A, CN101224593A, CN101007412A. [0003] At present, the carbonized wood processed by the existing known technology still has the following disadvantages: 1) After high-temperature carbonization, the ...

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): B27M1/08B27K3/08B27K3/16B27K5/04B27M1/06
Inventor 李民李家宁马心李晓文林位夫谢贵水陈青秦韶山黄华孙
Owner RUBBER RES INST CHINESE ACADEMY OF TROPICAL AGRI SCI
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