Pre-exposure treatment for increasing plasticity of rice husk for rice husk board manufacturing

摘要

Chaff has a 40% cellulose content and is slightly lower than wood, but the overall amount of cellulose, hemicellulose and lignin is similar. However, it has high silica content and has a grain shape of rice grains, so it is not good formability when manufacturing boards, and adhesive coated on the surface of rice husk has poor contact surface between rice hulls. In comparison, the bending strength is only 1 / 3-1 / 4.;In the past, chaff boards can be largely divided into two methods. First, chaff boards are manufactured using synthetic resin adhesive, cement or gypsum as the size of chaff produced. The second method is to prepare a board using various adhesives or binders by grinding or crushing rice hulls. This method also has a decrease in strength even if the fiber length is shortened to improve moldability.;Therefore, the present invention is a method of pretreatment (softening) which can bring about an increase in strength while maintaining the original size as possible, while improving the formability which is the most problematic in manufacturing chaff plate or board so far. It is a decay treatment that does not become desquamation under much weaker conditions (20-25 kg / cm ² for about 1 minute) than the treatment of high temperature and high pressure (70-80kg / cm ² , temperature 290 ℃), similar to that of wood . If sea islands are made of boards, unlike wood, they do not produce boards. Therefore, the sea islands are softened and the plasticization of the lignin flows at the same time without progress. This pre-explosion treatment method not only improves moldability but also increases the contact area between the chaff and the chaff, thereby increasing the efficiency of the adhesive, thereby doubling the strength of the chaff board.