The full cell method of wood pressure impregnation tank is to make the wood cells full of preservative solution, so that the wood retains a lot of preservatives. This method is suitable for treating wood with water-borne wood preservative and coal creosote oil. The following is a brief introduction to the five stages of the treatment of wood preservative pressure impregnation tank
1. In the vacuum stage before the pressure impregnation tank of wood:
Put the wood into the pressure impregnation tank, close the door of the tank, start the vacuum pump, vacuum the impregnation tank (generally - 0.080 ～ - 0.095mpa), keep for 15 minutes, so as to extract the air in the wood cell cavity, make the wood easy to be impregnated by preservatives, and reduce the anti-corrosion agent backwashing out during pressure relief, so as to retain more preservatives in the wood.
2. In the stage of adding preservative to the pressure impregnation tank of wood:
In the case of not turning off the vacuum pump, that is, keeping the original vacuum, add preservative solution. If the vacuum pump is turned off before the pressure impregnation tank is filled with preservative, the residual air in the impregnation tank or the vapor generated by the treatment solution will be compressed to the upper part of the impregnation tank. When the preservative solution is added continuously, these gases will fill the space in the upper wood of the timber pile which has been evacuated during vacuum pumping, so that this part of the timber can absorb a small amount of water Preservative solution, resulting in the same batch of wood up and down uneven results.
3. During the pressurization stage of wood preservation tank:
When the preservative is filled with pressure, close the vacuum pump, remove the vacuum, apply pressure (hydraulic pressure or air pressure) to reach the required pressure (generally 0.8-1.5mpa) and keep for a period of time (generally 2-6 hours), until the required anti-corrosion dose has been deeply pressed into the wood, or to the point where the wood refuses to absorb the preservative solution until. At the end of the pressure stage, when the pressure is removed, due to the expansion of a small amount of air compressed in the wood, 5-15% of the preservative solution absorbed by the wood in the pressure stage will recoil from the wood and return to the pressure impregnation tank.
4. During the discharging stage of pressure impregnation tank for wood
After the pressure is released, the preservative solution in the pressure infusion tank is returned to the preservative solution storage tank by the gravity of the preservative solution or by the discharge pump.
5. In the vacuum stage after the pressure infusion tank:
After the preservative solution is exhausted, close all valves, connect the vacuum pump and start the post vacuum phase. The vacuum degree of the rear vacuum can be the same as that of the front vacuum (- 0.080 ～ -0.095mpa), or slightly lower, for 10-30 minutes. Then remove the vacuum and let out the preservative solution extracted in the post vacuum stage. Open the door of the tank and take out the treated wood. The anticorrosion treatment has been completed.