摘要 |
<p>A method and apparatus for applying a fluid preservative to wood or wood products has a work tank for maintaning a predetermined concentration of preservative in the fluid. The work tank is equipped with a heater to keep the temperature of the fluid and the preservative in the work tank at a predetermined level. Hot fluid and preservative is drawn under a vacuum, initially from the work tank. On filling a pressure vessel, a pressure pump then supplies the preservative and fluid mixture under pressure to the pressure vessel in which the wood or wood product is being treated. As the treatment process depletes the preservative in the fluid, through absorption in the wood, the depleted fluid is circulated back to the work tank where it is heated and more preservative is added to restore the concentration of preservative in the fluid to a desired level. The fluid, replenished with preservative, is then pumped into the pressure vessel. In this way a more uniform distribution of preservative in a desired concentration is achieved in the treated wood or wood product.</p> |