Method for producing wood fiberboards

A method for the production of wood fiberboards, comprising the following steps:

• a) crushing wood into wood chips,
• b) hydrothermally pretreating the wood chips with steam in a pre-steaming bin at a temperature of 100 to 180° C. and a pressure of 1 to 10 bar,
• c) grinding the pre-treated wood chips into fine wood particles in a refiner in a presence of steam at a temperature of 150 to 200° C. and a pressure of 4.5 to 16 bar,
• d) gluing and drying the fine wood particles, wherein the drying of the fine wood particles can also be carried out prior to gluing,
• e) forming mats from bonded fibers and precompacting the mats,
• f) pressing the glued and dried fine wood particles at a temperature of 170 to 240° C. into wood fiberboards,
• wherein at least one of steps d) to e) is carried out in a presence of one or a plurality of surfactants added in step d) and/or in step e);
• wherein the surfactants are selected from alkyl polyglycosides of the general formula (IIa) or (IIb)
• R1O(R2O)b(Z)a (IIa)
• R1O(Z)a(R2O)bH (IIb)
• wherein
• R1=linear or branched C4-C30 alkyl,
• R2=C2-C4 alkylene,
• Z=independently, one sugar radical each with 5 or 6 carbon atoms,
• b=0-12, and
• a=1-15;
• and
• wherein in step d) at least one surfactant is injected with the glue into the blow line and/or in step e) at least one surfactant is sprayed on or under the precompressed mat.