# US 11,299,851 B2 · Method for producing pulp fibers to be saccharified > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,299,851 B2 - Document ID: US11299851B2 - Status: Granted - Kind: B2 - Application number: 16/771,746 - Filed: 2017-12-20 - Published: 2020-12-24 - Granted: 2022-04-12 - Earliest claimed: 2017-12-20 - Assignees: Unicharm Corporation - Applicants: Unicharm Corporation - Inventors: Kouichi Yamaki; Naoto Ohashi; Takayoshi Konishi - Web page: https://patentgrep.com/patent/US11299851B2 ## CPC - D21C 5/022: {Chemicals therefor} - D21C 9/153: with ozone - B09B 3/32: Compressing or compacting - B09B 3/35: Shredding, crushing or cutting - B09B 3/70: Chemical treatment, e.g. pH adjustment or oxidation (involving an extraction step B09B3/80) - C08J 11/00: Recovery or working-up of waste materials (recovery of plastics B29B17/00; polymerisation processes involving purification or recycling of waste polymers or their depolymerisation products C08B, C08C, C08F, C08G, C08H) - C08J 11/04: of polymers - C13K 1/02: obtained by saccharification of cellulosic materials (manufacture of fodder A23K10/32) - D21C 5/02: Working-up waste paper (mechanical part D21B1/08, D21B1/32) - D21C: PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR - B09B: DISPOSAL OF SOLID WASTE NOT OTHERWISE PROVIDED FOR - C08J: WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H (working, e.g. shaping, of plastics B29) - C13K: SACCHARIDES OBTAINED FROM NATURAL SOURCES OR BY HYDROLYSIS OF NATURALLY OCCURRING DISACCHARIDES, OLIGOSACCHARIDES OR POLYSACCHARIDES (chemically synthesised sugars or sugar derivatives C07H; polysaccharides, e.g. starch, derivatives thereof C08B; malt C12C; fermentation or enzyme-using processes for preparing compounds containing saccharide radicals C12P19/00; production of sucrose C13B) ## Abstract Provided is a method for producing pulp fibers to be saccharified, whereby it becomes possible to reduce the amount of a highly water-absorbable polymer and therefore increase the collection efficiency in the production of a saccharified solution when pulp fibers for a saccharified liquid is produced from a dirty absorbent article. The method is a method for producing pulp fibers to be saccharified, from pulp fibers in a dirty absorbent article. The method includes: a solid-liquid separation step (S18) of crushing up a highly water-absorbable polymer while separating an inactivated aqueous solution containing pulp fibers and the highly water-absorbable polymer both separated from a dirty absorbent article into a solid material (98) containing the pulp fibers and the highly water-absorbable polymer and a liquid material (E) containing the highly water-absorbable polymer and the inactivated aqueous solution; and a removal step (S21) of washing away the remaining highly water-absorbable polymer by washing the separated solid pulp fibers in a solution or another means to produce pulp fibers to be saccharified. ## Claims ### Claim 1 A method of manufacturing pulp fibers for saccharification from pulp fibers of used absorbent articles, comprising: a first solid-liquid separation process that receives a first inactivation aqueous solution which includes the pulp fibers and superabsorbent polymers which are separated from the used absorbent articles and outputs a mixed solution which includes the pulp fibers and the superabsorbent polymers that could not be removed from the pulp fibers, and a second inactivation aqueous solution, containing superabsorbent polymers, a second solid-liquid separation process that receives the mixed solution from the first solid-liquid separation process and outputs a third inactivation solution containing superabsorbent polymers and a solid matter which includes pulp fibers and superabsorbent polymers that have been squashed, and removing the squashed superabsorbent polymers from the solid matter by delivering the solid matter to a pre-treatment device that washes the solid matter with a liquid that includes an oxidizing agent to oxidatively decompose the superabsorbent polymers which remain in the pulp fibers and change them into organic matters with low molecular weights which are soluble in the liquid thereby reducing the viscosity of the pulp fibers before delivering the pulp fibers to a treatment device which further reduces the superabsorbent polymers from the pulp fibers. ### Claim 2 (depends on 1) The method according to claim 1, wherein the second solid-liquid separation process includes a squashing process of squashing the superabsorbent polymers which remain in the pulp fibers by treating the inactivation aqueous solution which includes the pulp fibers and the superabsorbent polymers by a pressure type dehydration method. ### Claim 3 (depends on 1) The method according to claim 1, further comprising a process of separating a portion of the superabsorbent polymers and the inactivation aqueous solution from the inactivation aqueous solution which includes the pulp fibers and the superabsorbent polymers before the solid-liquid separation process. ### Claim 4 (depends on 1) The method according to claim 1, further comprising, before the first solid-liquid separation process, a process of crushing the used absorbent articles within the inactivation aqueous solution, and a process of separating the inactivation aqueous solution which includes the pulp fibers and the superabsorbent polymers from the inactivation aqueous solution which includes crushed matter obtained by the process of crushing the used absorbent articles. ### Claim 5 (depends on 1) The method according to claim 1, wherein the oxidizing agent is ozone. ### Claim 6 (depends on 1) The method according to claim 1, wherein the inactivation aqueous solution is an acidic aqueous solution. ### Claim 7 (depends on 1) The method according to claim 1, further comprising, after the removal process, a saccharification process of manufacturing a saccharification solution by saccharifying the pulp fibers for saccharification.