Patent ID: 6206309
Filing Date: 2001-03-27
Classification: B02C,D21D

Abstract:
A method for refining lignocellulosic material between a pair of relatively rotary refining elements forming an annular outer refining zone and a central feed zone therebetween, said method including feeding said lignocellulosic material to said central feed zone at a first rate, accelerating said lignocellulosic material from said central feed zone into said annular outer refining zone at a second rate without lignocellulosic material build up in said central feed zone and substantially without working said lignocellulosic material in said central feed zone, the density of said lignocellulosic material in said central feed zone being a maximum of about 10 kg/m.sup.3, said second rate being substantially greater than said first rate, and mechanically working said lignocellulosic material in said annular outer refining zone wherein said relatively rotary refining elements have a relative speed of greater than about 50 m/sec.