BigPatents India

Biological Softening of Lignocelluloses Material for Preparing Binder less Board . The Binder less Board is a general term used to cover the board or sheet material having a density greater than 0.4 g/cm³. Forest based woody materials are being conventionally used for board making. Crop residues, which are renewable in nature, form an attractive and an alternate proposition to cope with the present day shortage of raw materials faced by paper and board industries. Conventionally, binder less boards are prepared by feeding wooden chips into a thermo mechanical pulpier (160ºC) for a specified time under pressure. The thermally softened pulp is made and pressed after dewatering at 160ºC in a three-step pressure cycle to obtain binder less boards. The softened lignin at high temperature in the pulp matrix acts as the binder when pressed at an elevated temperature. The thermal softening of lignin is replaced by biological softening by subjecting the mechanically prepared pulp to a microbial consortium for 24 hours at room temperature followed by mat formation and pressing in a three step pressure cycle The biological softening process offers several advantages viz., replacement of initial thermal process, discharge of less toxic effluents, economical and ecofriendly. Drawing: 00 Sheets. Total Pages: 8. Fig. Nil