
CONTINUOUS IMPREGNATION OF WOOD FROM THE END FACE UNDER PRESSURE WITH VARIOUS COMPOSITIONS
Author(s) -
И. Н. Медведев,
Dmitriy Parinov,
Владимир Шамаев
Publication year - 2021
Language(s) - English
Resource type - Conference proceedings
DOI - 10.34220/mmeitsic2021_245-249
Subject(s) - autoclave , materials science , composite material , larch , pulp and paper industry , beech , steaming , humidity , chemistry , botany , food science , physics , engineering , metallurgy , biology , thermodynamics
Modern impregnating compositions for wood can significantly improve its characteristics. Water-soluble and oily antiseptics, flame retardants, strengthening and plasticizing modifiers, and dyes are used as impregnating compositions. By means of impregnation, substances are introduced into the wood that increase its characteristics such as plasticity, hydrophobicity, bio- fire resistance and shape stability. But, the indicator of certain properties after impregnation of wood with a certain composition depends on the depth of impregnation, on the uniformity of the distribution of the impregnating composition over the entire volume of wood, on the concentration of the impregnating composition in the wood, on the chosen method of impregnation. It also affects which group of impregnability a particular wood belongs to, according to the breed composition, the division is made into 3 groups: 1-easily nourished rocks (birch, alder, beech, aspen sapwood, poplar, pine); 2-moderately impregnated rocks (cedar, oak, ash, maple, linden, pine core); 3-hard- to-impregnate rocks (spruce, larch, fir). Spruce and larch are considered to be almost impervious to deep impregnation of the rocks, because of their clogged pores with resin. In the autoclave method of impregnation with water solutions, the wood must be dried to a humidity of 40% before impregnation, and to a humidity of 30% when impregnated with oily liquids. After impregnation, a re-drying operation follows. Another significant disadvantage of autoclave impregnation is its uneven distribution of the absorbed liquid in the workpieces, in some workpieces too much impregnating liquid penetrates, and in others not enough. In order to avoid two dries and to be able to set the volume of liquid that the wood will absorb, as well as to ensure the uniformity of impregnation over the entire volume of wood, it is proposed to develop a technology and equipment for end-to-end impregnation of coniferous wood from the end under pressure of raw, rounded logs with a diameter of 15-35 cm and a length of 3 m.