Patent ID: 6355138
Filing Date: 2002-03-12
Classification: D21C,D21H

Abstract:
A method of continuously loading fibers in a fiber suspension with calcium carbonate, the fibers including a fiber wall surrounding a lumen, said method comprising the steps of:mixing a reactant solid comprising at least one of calcium oxide and calcium hydroxide into the fiber suspension with a resultant initial process pH of between 11 and 12; transporting the fiber suspension at a consistency of between approximately 15 and 30% into an inner chamber of a closed reactor, said reactor including a first fluffer and a second fluffer, said inner chamber disposed between and interconnecting said first fluffer and said second fluffer, said reactor further including a mixing element mounted within said inner chamber; injecting a reactant gas into said reactor, whereby said reactor is pressurized to a reaction pressure of between 5 and 150 pounds per square inch; controlling a reaction temperature of the fiber suspension within said reactor between âˆ’10Â° C. and 80Â° C.; and loading fibers within the fiber suspension with calcium carbonate as a result of a chemical reaction between said reactant solid and said reactant gas in said reactor over a predetermined reaction time, said loading step including the sub-step of growing a specific type of calcium carbonate crystals on the fiber walls of said fibers dependent upon said initial process pH, said reaction temperature, said pressure and said reaction time.