A deep degreasing method for wood vacuum heat treatment

Abstract

A provided deep degreasing method for timber through vacuum heat treatment comprises: selecting wood with certain thickness, piling wood in an enclosed degreasing tank; heating wood to enable wood to have a drying temperature of 40 DEG C-60 DEG C, then reducing the air pressure to a first vacuum degree, so as to adjust the water content of wood to be 5%-12%; continuing to reduce the air pressure to a second vacuum degree, and also raising the temperature to a preheating temperature, so as to dry wood to be absolutely dry; and keeping the second vacuum degree, continuing to raise the temperature to a degreasing temperature, and staying for a preset degreasing period, so as to perform deep degreasing processing on wood. The wood degreasing method increases the degreasing depth on wood, improves the wood degreasing efficiency of a conventional degreasing method, and also improves the wood dimension stability without causing substantial color variation.

Description

Technical field [0001] The invention relates to a wood vacuum heat treatment deep degreasing method, that is, high temperature treatment of the wood under the condition of lower than atmospheric pressure. The degreasing method increases the degreasing depth of the wood, improves the wood degreasing efficiency of the existing degreasing method, and at the same time improves The dimensional stability of the wood, the color change is not significant. Background technique [0002] The conifers of Pinaceae, Pinus, Spruce, Larch, Pseudotsuga, Silver Fir, and Taxus chinensis have normal resin channels in their wood structures, which secrete resin and are rich in resin content. In the process of wood processing and utilization, high content of resin affects the subsequent sawing, sanding, painting and gluing of wood. Once the ambient temperature is high, the resin will penetrate to the wood surface and pollute wood products. Therefore, this type of Wood needs to be degreasing treatment ...

AI Technical Summary

Problems solved by technology

[0004] Due to the diversity of wood species, the wood characteristics are different, especially for some woods with poor permeability and difficult impregnation, such as larch, masson pine, etc., it is difficult to use chemical agents for effective degreasing treatment

Therefore, with regard to this type of wood, there are still problems in improving its degreasing rate, degreasing depth, etc.; higher

In terms of wood degreasing by physical methods, the patent of CN101633189A discloses a method for degreasing pine wood, which uses a hot press to degrease pine wood twice. This method limits the thickness of pine wood samples and cannot achieve deep degreasing of wood. There are certain limitations in the degreasing treatment of large quantities of wood

The patent of CN103791694A discloses a method for drying and degreasing pine wood, which uses steam to heat the drying kiln to a temperature of 70-75°C and maintains it for 150-200 hours. This process takes a relatively long time and reduces production efficiency

In terms of wood comprehensive treatment and degreasing, the patent of CN1204569A discloses a method and equipment for degreasing modification of pine wood, which adopts two methods of chemical liquid treatment and steam drying treatment, but there are still defects in the existing chemical liquid chemical degreasing method

At the same time, because degreasing and drying cannot be carried out simultaneously in this method, after the wood is degreased in the degreasing tank, it needs to be transported to the drying kiln for drying again, and a steam generator is needed in the steam drying process, so the process equipment cost and manpower Higher cost reduces the efficiency of wood degreasing treatment

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