A method of obtaining rayon fibers from cellulose waste is provided. The method includes extracting alpha-cellulose from cellulose waste, dissolving the alpha-cellulose in a cuoxam solution, obtained by reacting gaseous ammonia with an aqueous solution of copper hydroxide, to obtain a chemically modified cellulose. The chemically modified cellulose was extruded in an acid bath to obtain a precipitate. The precipitate was further neutralized to obtain the rayon fibers.

A method of obtaining rayon fibers from cellulose waste is provided. The method includes extracting alpha-cellulose from cellulose waste, dissolving the alpha-cellulose in a cuoxam solution, obtained by reacting gaseous ammonia with an aqueous solution of copper hydroxide, to obtain a chemically modified cellulose. The chemically modified cellulose was extruded in an acid bath to obtain a precipitate. The precipitate was further neutralized to obtain the rayon fibers.

A ragger system for removing solid debris from a pulper vessel of a pulping system is disclosed. The ragger system includes a ragger operable to pull a tail of solid debris from the pulper vessel. The ragger includes a puller mechanism, a puller drive, a rider roll, and a pressure device to adjust a pressure of the rider roll on the tail between the puller mechanism and the rider roll. The ragger system includes a measurement device for determining attributes of the tail, operating conditions of the pulping system or ragger, or combinations of these. The ragger system includes a control system that measures input variables with the measurement devices, determines the attributes of the tail or operating conditions from the input variables, and adjusts a withdrawal rate, pull direction, pressure, rider roll torque or speed, or combinations thereof to maintain continuity of operation of the ragger.

A bale of sheets made of waste/recycle cellulose fibers and cellulose ester (CE) staple fibers can be fed to a hydropulper. The CE staple fibers have: i. a denier per filament (DPF) of less than 3, or ii. a cut length of less than 6 mm, or iii. crimping, or iv. a combination of any two or more of (i)-(iii).

The bales can be fed and dropped in as entire bales to a hydropulper, or a blend tank directly or indirectly in fluid communication with a hydropulper, using the same feed system employed for feeding cellulose to the hydopulper and avoiding having to defiberize by pulling or drawing fibers from a box container into a hydropulper. The waste/recycle cellulose fibers and CE staple fibers can be co-refined prior to making the bale of sheets.

A bale of sheets made of waste/recycle cellulose fibers and cellulose ester (CE) staple fibers can be fed to a hydropulper. The CE staple fibers have: i. a denier per filament (DPF) of less than 3, or ii. a cut length of less than 6 mm, or iii. crimping, or iv. a combination of any two or more of (i)-(iii).

The bales can be fed and dropped in as entire bales to a hydropulper, or a blend tank directly or indirectly in fluid communication with a hydropulper, using the same feed system employed for feeding cellulose to the hydopulper and avoiding having to defiberize by pulling or drawing fibers from a box container into a hydropulper. The waste/recycle cellulose fibers and CE staple fibers can be co-refined prior to making the bale of sheets.

A recycled pulp that is reusable sanitary products is efficiently manufactured by recovering pulp fiber from used sanitary products containing the pulp fiber and a polymer absorbent. The method of the present invention comprises: a step applying a mechanical force to the used sanitary products in an aqueous solution containing a polyvalent metal ion or an acidic aqueous solution with a pH of 2.5 or lower and thus degrading the used sanitary products into the pulp fiber and other materials; a step separating the pulp fiber from the mixture of the pulp fiber and other materials that has been formed in the degradation step; and a step treating the pulp fiber thus separated with an ozone-containing aqueous solution with a pH of 2.5 or lower.

A recycled pulp that is reusable sanitary products is efficiently manufactured by recovering pulp fiber from used sanitary products containing the pulp fiber and a polymer absorbent. The method of the present invention comprises: a step applying a mechanical force to the used sanitary products in an aqueous solution containing a polyvalent metal ion or an acidic aqueous solution with a pH of 2.5 or lower and thus degrading the used sanitary products into the pulp fiber and other materials; a step separating the pulp fiber from the mixture of the pulp fiber and other materials that has been formed in the degradation step; and a step treating the pulp fiber thus separated with an ozone-containing aqueous solution with a pH of 2.5 or lower.

A swirling flow generation device includes a first pipe having a first pipe axis and through which gas passes, a second pipe having a second pipe axis in a direction different from the first pipe axis and communicates with downstream of the first pipe, and an airflow changing unit provided in the first pipe and having an opening eccentric from the first pipe axis. A swirling flow is formed in the second pipe as the center of the airflow passed through the opening flows into the second pipe at a position that is eccentric from the second pipe axis.

A fiber body manufacturing method includes: a dispersing step of dispersing a mixture containing a defibrated material which includes fibers and a binding agent which exhibits a binding property by moisture absorption, the mixture having a moisture content of 10 to 30 percent by weight; a depositing step of depositing the mixture dispersed in the dispersing step; a humidifying step of imparting moisture by water vapor or mist to the binding agent in a deposit deposited in the depositing step so as to exhibit the binding property; and a forming step of forming the deposit humidified in the humidifying step into a fiber body.

A fiber body manufacturing method includes: a dispersing step of dispersing a mixture containing a defibrated material which includes fibers and a binding agent which exhibits a binding property by moisture absorption, the mixture having a moisture content of 10 to 30 percent by weight; a depositing step of depositing the mixture dispersed in the dispersing step; a humidifying step of imparting moisture by water vapor or mist to the binding agent in a deposit deposited in the depositing step so as to exhibit the binding property; and a forming step of forming the deposit humidified in the humidifying step into a fiber body.