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CN-121976407-A - High-yield low-carbon pulping system and process for recycled waste paper fibers

CN121976407ACN 121976407 ACN121976407 ACN 121976407ACN-121976407-A

Abstract

The invention relates to the technical field of papermaking pulping, and discloses a high-yield low-carbon pulping system and a high-yield low-carbon pulping process for recycled waste paper fibers, wherein the high-yield low-carbon pulping system comprises a pulping system, a coarse screening system, a grading system, a deslagging system and a thermal dispersion system, the deslagging system comprises a long fiber deslagging unit and a short fiber deslagging unit, a slurry distributor is arranged between the grading system and the long fiber deslagging unit as well as between the grading system and the short fiber deslagging unit, a fluffer is connected to a tailings outlet of the long fiber deslagging unit and the short fiber deslagging unit, and a discharge end of the fluffer is communicated with a feed end of the thermal dispersion system; through the synergistic effect of up-flow screening, grading deslagging and tailing recycling, the waste paper fiber utilization efficiency is greatly improved, the resource waste is effectively reduced, meanwhile, the energy consumption and pollutant emission in the pulping process are remarkably reduced, the pulp purifying effect is fully ensured, the impurities such as sticky matters are effectively removed, and the good pulp cleanliness is improved.

Inventors

  • LI WENBIN
  • WANG XIAOTING

Assignees

  • 江苏理文造纸有限公司

Dates

Publication Date
20260505
Application Date
20260130

Claims (10)

  1. 1. The utility model provides a high-yield low-carbon pulping system of circulation waste paper fibre, its characterized in that, including garrulous thick liquid system, coarse screen system, grading system, deslagging system and the heat dispersion system of establishing ties in proper order, coarse screen system adopts up-flow pressure sieve, deslagging system includes long fiber deslagging unit and short fiber deslagging unit, grading system with long fiber deslagging unit with be provided with the thick liquids distributor between the short fiber deslagging unit, long fiber deslagging unit with the tailings exit linkage of short fiber deslagging unit has the fluffer, the discharge end of fluffer with the feed end intercommunication of heat dispersion system, just the discharge end of heat dispersion system is connected with the thick liquid storage unit.
  2. 2. The recycled waste paper fiber high-yield low-carbon pulping system according to claim 1, wherein the long fiber deslagging unit adopts five sections of low-concentration deslagging units connected in series, the short fiber deslagging unit adopts four sections of low-concentration deslagging units connected in series, the low-concentration deslagging unit adopts a spiral pulp feeding structure, a balancing water device and a backwash water device are arranged in the low-concentration deslagging unit, and an automatic intermittent deslagging mechanism is arranged at the bottom of the low-concentration deslagging unit.
  3. 3. The recycled waste paper fiber high-yield low-carbon pulping system of claim 2, wherein the upflow pressure screen comprises a screen body, a double-layer structure upflow screen cylinder is arranged on the inner side of the screen body, and a rotor is arranged on the inner side of the double-layer structure upflow drying cylinder.
  4. 4. The recycled waste paper fiber high-yield low-carbon pulping system according to claim 3, wherein the fluffer comprises a sectional screen cylinder, a sectional rotor and an annular dilution water ring, the sectional screen cylinder is axially divided into a coarse fluffing area and a fine fluffing area, and the sectional rotor is respectively provided with a coarse fluffing block and a fine fluffing block corresponding to the coarse fluffing area and the fine fluffing area.
  5. 5. The recycled waste paper fiber high-yield low-carbon pulping system of claim 4, wherein the diameter of an inner screen of the upflow screen cylinder with the double-layer structure is 0.1-0.2mm, the diameter of an outer supporting screen is 5mm, the height-diameter ratio of the screen cylinder is 3:1-5:1, and the thickness of blades of the rotor is 2-3mm.
  6. 6. A recycled waste paper fiber high-yield low-carbon pulping process, which adopts the pulping system as claimed in any one of claims 1 to 5, and is characterized by comprising the following steps: S1, adding waste paper raw materials into a pulping system, controlling the pulping concentration to be 3-5% and the pulping time to be 20-30min, and obtaining initial pulp; S2, feeding the initial slurry into an upflow pressure screen, controlling the slurry feeding pressure to be 0.15-0.25MPa, the slurry feeding concentration to be 1.0-1.5%, and the rotor linear speed to be 25-35m/S, and separating light and heavy impurities to obtain screened slurry; S3, separating long fibers and short fibers through a grading system, respectively sending the long fibers and the short fibers into a long fiber deslagging unit and a short fiber deslagging unit, controlling the pulp feeding concentration to be 0.5-0.8% and the pulp feeding pressure to be 0.2-0.3MPa, and obtaining deslagged pulp after automatic intermittent deslagging; S4, collecting tailings of the deslagging unit, pretreating the tailings by a grid screen, then sending the tailings into a fluffer, controlling the rotating speed of a rotor to 1800-2200r/min, injecting dilution water for elutriation and separation, recovering good pulp, and adjusting the concentration to 1.0-1.5%; S5, mixing the deslagged slurry with the recovered good slurry, sending the mixture into a thermal dispersion system, dispersing the mixture at 80-90 ℃ for 10-15min, and storing the mixture in a slurry storage unit.
  7. 7. The recycled waste paper fiber high-yield low-carbon pulping process of claim 6, wherein the temperature of the dilution water is 40-50 ℃, the injection pressure is 0.1-0.15MPa, and the mass ratio of the dilution water to the tailings is 1:1-1:2.
  8. 8. The process for pulping recycled waste paper fiber with high yield and low carbon according to claim 7, wherein the automatic intermittent type slag discharging mechanism is used for discharging slag at a slag discharging interval of 5-10min for 10-20s, and the slag discharging operation is triggered when the stacking height of impurities reaches 5-8 cm.
  9. 9. The recycling waste paper fiber high-yield low-carbon pulping process according to claim 8, wherein the water injection pipeline of the water balancing device is 10cm away from the pulp inlet, the flow adjustment range is 0.5-1.0m < 3 >/h, the backflushing water pressure of the backflushing water equipment is 0.2-0.3MPa, and the backflushing water period is 5-10min.
  10. 10. The process for pulping recycled waste paper fibers with high yield and low carbon according to claim 9, wherein the waste paper raw material is cardboard paper, corrugated base paper, coated paper board manufactured by secondary fiber or uncoated paper board, and if the waste paper raw material is corrugated base paper, the pulp feeding pressure of the short fiber slag remover is adjusted to be 0.18-0.22MPa, and the pulp feeding concentration is adjusted to be 0.6-0.7%.

Description

High-yield low-carbon pulping system and process for recycled waste paper fibers Technical Field The invention relates to the technical field of papermaking pulping, in particular to a high-yield low-carbon pulping system and process for recycled waste paper fibers. Background The paper industry is an important basic industry of national economy, and waste paper pulping and papermaking have remarkable resource saving and environmental protection values, however, the existing waste paper pulping process faces a plurality of technical bottlenecks: (1) The fiber loss is serious, the fiber length is shortened, the strength is reduced after the waste paper is recycled for a plurality of times, and the fiber yield in the traditional pulping process is generally low; (2) The screening equipment is unreasonable, the traditional down-flow screening device is easy to cause high-quality impurities to impact the screen plate and the blades, equipment abrasion is caused, slurry is easy to accumulate and thicken at the bottom, screening efficiency is affected, and meanwhile, the traditional rotor blade is large in design pulse, high in energy consumption and low in sticky matter removal rate; (3) The deslagging system lacks pertinence, does not distinguish the characteristics of long fibers and short fibers, adopts uniform deslagging parameters, causes excessive deslagging loss of the long fibers and incomplete deslagging of the short fibers, and has generally higher fiber loss rate in the existing deslagging process; (4) The tailings resources are wasted, the tailings generated by the deslagging system contain a large amount of fibers which are not fully utilized, but the traditional process cannot effectively separate the fibers from impurities, and the tailings are directly discarded, so that resources are wasted, and environmental pollution is caused; (5) The energy consumption is higher than 250kwh per ton of pulp in the traditional waste paper pulping process, the energy consumption of a main pulping system is generally higher than 80kgce/t, and the low-carbon development requirement is not met. Therefore, there is a need to design a pulping system and process with a complete process of collaborative optimization screening, deslagging and tailings recycling, so as to achieve the aims of high yield, low energy consumption, low emission and resource circulation. Disclosure of Invention The invention aims to overcome the defects in the prior art and provide a high-yield low-carbon pulping system and process for recycling waste paper fibers, so that the pulping yield is remarkably improved, the energy consumption is greatly reduced, and the recycling rate of resources is improved. In order to achieve the above purpose, the invention adopts the following technical scheme: according to the first aspect, the high-yield low-carbon pulping system for recycling waste paper fibers comprises a pulping system, a coarse screening system, a grading system, a deslagging system and a heat dispersing system which are sequentially connected in series, wherein the coarse screening system adopts an up-flow pressure screen, the deslagging system comprises a long fiber deslagging unit and a short fiber deslagging unit, a slurry distributor is arranged between the grading system and the long fiber deslagging unit as well as between the grading system and the short fiber deslagging unit, a fluffer is connected with a tailings outlet of the long fiber deslagging unit, a discharge end of the fluffer is communicated with a feed end of the heat dispersing system, and a discharge end of the heat dispersing system is connected with a slurry storage unit. Optionally, the long fiber deslagging unit adopts five sections low-concentration deslagging units in series connection, the short fiber deslagging unit adopts four sections low-concentration deslagging units in series connection, the low-concentration deslagging unit adopts a spiral pulp feeding structure, a balancing water device and a back flushing device are arranged in the low-concentration deslagging unit, and an automatic intermittent deslagging mechanism is arranged at the bottom of the low-concentration deslagging unit. Optionally, the upflow pressure screen comprises a screen body, a double-layer structure upflow screen cylinder is arranged on the inner side of the screen body, and a rotor is arranged on the inner side of the double-layer structure upflow screen cylinder. Optionally, the fluffer includes sectional type screen drum, hierarchical rotor and annular dilution water ring, the sectional type screen drum is divided into coarse fluffing district and smart fluffing district along the axial, correspond coarse fluffing district and smart fluffing district on the hierarchical rotor and be provided with coarse fluffing district and smart fluffing district respectively. Optionally, the aperture of the inner layer screen of the upflow type screen cylinder with the double-layer structu