CN114960248A - Preparation method of bamboo pulp for Lyocell fiber and product thereof - Google Patents
Preparation method of bamboo pulp for Lyocell fiber and product thereof Download PDFInfo
- Publication number
- CN114960248A CN114960248A CN202210768213.3A CN202210768213A CN114960248A CN 114960248 A CN114960248 A CN 114960248A CN 202210768213 A CN202210768213 A CN 202210768213A CN 114960248 A CN114960248 A CN 114960248A
- Authority
- CN
- China
- Prior art keywords
- pot
- bamboo
- pulp
- liquid
- prehydrolysis
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 235000017166 Bambusa arundinacea Nutrition 0.000 title claims abstract description 165
- 235000017491 Bambusa tulda Nutrition 0.000 title claims abstract description 165
- 241001330002 Bambuseae Species 0.000 title claims abstract description 165
- 235000015334 Phyllostachys viridis Nutrition 0.000 title claims abstract description 165
- 239000011425 bamboo Substances 0.000 title claims abstract description 165
- 229920000433 Lyocell Polymers 0.000 title claims abstract description 34
- 238000002360 preparation method Methods 0.000 title claims abstract description 23
- 239000007788 liquid Substances 0.000 claims abstract description 84
- 238000010438 heat treatment Methods 0.000 claims abstract description 43
- 238000000605 extraction Methods 0.000 claims abstract description 27
- 238000004519 manufacturing process Methods 0.000 claims abstract description 22
- 238000000034 method Methods 0.000 claims description 47
- 238000010306 acid treatment Methods 0.000 claims description 43
- 239000003513 alkali Substances 0.000 claims description 36
- 239000000413 hydrolysate Substances 0.000 claims description 33
- 238000004061 bleaching Methods 0.000 claims description 29
- 239000007791 liquid phase Substances 0.000 claims description 29
- 238000005406 washing Methods 0.000 claims description 23
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims description 21
- 239000000463 material Substances 0.000 claims description 21
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 18
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 18
- 239000002002 slurry Substances 0.000 claims description 14
- 238000010411 cooking Methods 0.000 claims description 13
- 239000002738 chelating agent Substances 0.000 claims description 12
- 238000004064 recycling Methods 0.000 claims description 12
- 230000002378 acidificating effect Effects 0.000 claims description 9
- 230000003197 catalytic effect Effects 0.000 claims description 9
- KCXVZYZYPLLWCC-UHFFFAOYSA-N EDTA Chemical compound OC(=O)CN(CC(O)=O)CCN(CC(O)=O)CC(O)=O KCXVZYZYPLLWCC-UHFFFAOYSA-N 0.000 claims description 8
- QPCDCPDFJACHGM-UHFFFAOYSA-N N,N-bis{2-[bis(carboxymethyl)amino]ethyl}glycine Chemical compound OC(=O)CN(CC(O)=O)CCN(CC(=O)O)CCN(CC(O)=O)CC(O)=O QPCDCPDFJACHGM-UHFFFAOYSA-N 0.000 claims description 8
- 229960001484 edetic acid Drugs 0.000 claims description 8
- 238000011049 filling Methods 0.000 claims description 8
- 229960003330 pentetic acid Drugs 0.000 claims description 8
- 230000001502 supplementing effect Effects 0.000 claims description 7
- XBDQKXXYIPTUBI-UHFFFAOYSA-N dimethylselenoniopropionate Natural products CCC(O)=O XBDQKXXYIPTUBI-UHFFFAOYSA-N 0.000 claims description 6
- BDAGIHXWWSANSR-UHFFFAOYSA-N methanoic acid Natural products OC=O BDAGIHXWWSANSR-UHFFFAOYSA-N 0.000 claims description 6
- 238000003860 storage Methods 0.000 claims description 6
- MGFYIUFZLHCRTH-UHFFFAOYSA-N nitrilotriacetic acid Chemical compound OC(=O)CN(CC(O)=O)CC(O)=O MGFYIUFZLHCRTH-UHFFFAOYSA-N 0.000 claims description 4
- GCLGEJMYGQKIIW-UHFFFAOYSA-H sodium hexametaphosphate Chemical compound [Na]OP1(=O)OP(=O)(O[Na])OP(=O)(O[Na])OP(=O)(O[Na])OP(=O)(O[Na])OP(=O)(O[Na])O1 GCLGEJMYGQKIIW-UHFFFAOYSA-H 0.000 claims description 4
- 235000019982 sodium hexametaphosphate Nutrition 0.000 claims description 4
- 239000001577 tetrasodium phosphonato phosphate Substances 0.000 claims description 4
- OSWFIVFLDKOXQC-UHFFFAOYSA-N 4-(3-methoxyphenyl)aniline Chemical compound COC1=CC=CC(C=2C=CC(N)=CC=2)=C1 OSWFIVFLDKOXQC-UHFFFAOYSA-N 0.000 claims description 3
- 235000011054 acetic acid Nutrition 0.000 claims description 3
- 235000019253 formic acid Nutrition 0.000 claims description 3
- 230000003472 neutralizing effect Effects 0.000 claims description 3
- 235000019260 propionic acid Nutrition 0.000 claims description 3
- IUVKMZGDUIUOCP-BTNSXGMBSA-N quinbolone Chemical compound O([C@H]1CC[C@H]2[C@H]3[C@@H]([C@]4(C=CC(=O)C=C4CC3)C)CC[C@@]21C)C1=CCCC1 IUVKMZGDUIUOCP-BTNSXGMBSA-N 0.000 claims description 3
- 239000000203 mixture Substances 0.000 claims 1
- 239000002994 raw material Substances 0.000 abstract description 10
- 238000006243 chemical reaction Methods 0.000 abstract description 8
- LFTLOKWAGJYHHR-UHFFFAOYSA-N N-methylmorpholine N-oxide Chemical compound CN1(=O)CCOCC1 LFTLOKWAGJYHHR-UHFFFAOYSA-N 0.000 abstract description 6
- 239000002904 solvent Substances 0.000 abstract description 6
- 229920000875 Dissolving pulp Polymers 0.000 abstract description 5
- 229920002488 Hemicellulose Polymers 0.000 abstract description 5
- 230000007547 defect Effects 0.000 abstract description 5
- 239000000835 fiber Substances 0.000 abstract description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 28
- 229910052742 iron Inorganic materials 0.000 description 14
- 238000006460 hydrolysis reaction Methods 0.000 description 13
- 230000007062 hydrolysis Effects 0.000 description 12
- 230000000052 comparative effect Effects 0.000 description 11
- 238000007599 discharging Methods 0.000 description 10
- 239000000047 product Substances 0.000 description 10
- 230000000630 rising effect Effects 0.000 description 8
- 238000010521 absorption reaction Methods 0.000 description 7
- 238000006386 neutralization reaction Methods 0.000 description 7
- 239000013589 supplement Substances 0.000 description 7
- 238000006073 displacement reaction Methods 0.000 description 6
- 229920000609 methyl cellulose Polymers 0.000 description 6
- 239000001923 methylcellulose Substances 0.000 description 6
- 235000010981 methylcellulose Nutrition 0.000 description 6
- 238000006116 polymerization reaction Methods 0.000 description 6
- 239000011347 resin Substances 0.000 description 6
- 229920005989 resin Polymers 0.000 description 6
- 108010009736 Protein Hydrolysates Proteins 0.000 description 5
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 4
- 240000005499 Sasa Species 0.000 description 3
- 235000015874 Sinocalamus latiflorus Nutrition 0.000 description 3
- 244000092524 Sinocalamus latiflorus Species 0.000 description 3
- 238000009835 boiling Methods 0.000 description 3
- 229920005610 lignin Polymers 0.000 description 3
- 238000004321 preservation Methods 0.000 description 3
- 238000007670 refining Methods 0.000 description 3
- 239000002028 Biomass Substances 0.000 description 2
- SRBFZHDQGSBBOR-IOVATXLUSA-N D-xylopyranose Chemical compound O[C@@H]1COC(O)[C@H](O)[C@H]1O SRBFZHDQGSBBOR-IOVATXLUSA-N 0.000 description 2
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- 241000543810 Sasa veitchii Species 0.000 description 2
- 230000009920 chelation Effects 0.000 description 2
- 230000003749 cleanliness Effects 0.000 description 2
- 238000005265 energy consumption Methods 0.000 description 2
- HYBBIBNJHNGZAN-UHFFFAOYSA-N furfural Chemical compound O=CC1=CC=CO1 HYBBIBNJHNGZAN-UHFFFAOYSA-N 0.000 description 2
- 229910021645 metal ion Inorganic materials 0.000 description 2
- 229920001131 Pulp (paper) Polymers 0.000 description 1
- 229920000297 Rayon Polymers 0.000 description 1
- 240000009132 Sagittaria sagittifolia Species 0.000 description 1
- 235000006466 Sagittaria sagittifolia Nutrition 0.000 description 1
- TVXBFESIOXBWNM-UHFFFAOYSA-N Xylitol Natural products OCCC(O)C(O)C(O)CCO TVXBFESIOXBWNM-UHFFFAOYSA-N 0.000 description 1
- PYMYPHUHKUWMLA-UHFFFAOYSA-N arabinose Natural products OCC(O)C(O)C(O)C=O PYMYPHUHKUWMLA-UHFFFAOYSA-N 0.000 description 1
- 239000012752 auxiliary agent Substances 0.000 description 1
- SRBFZHDQGSBBOR-UHFFFAOYSA-N beta-D-Pyranose-Lyxose Natural products OC1COC(O)C(O)C1O SRBFZHDQGSBBOR-UHFFFAOYSA-N 0.000 description 1
- 229920002678 cellulose Polymers 0.000 description 1
- 239000001913 cellulose Substances 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 150000004676 glycans Chemical class 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000011031 large-scale manufacturing process Methods 0.000 description 1
- 238000011068 loading method Methods 0.000 description 1
- HEBKCHPVOIAQTA-UHFFFAOYSA-N meso ribitol Natural products OCC(O)C(O)C(O)CO HEBKCHPVOIAQTA-UHFFFAOYSA-N 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 229920001542 oligosaccharide Polymers 0.000 description 1
- 150000002482 oligosaccharides Chemical class 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 229920001282 polysaccharide Polymers 0.000 description 1
- 239000005017 polysaccharide Substances 0.000 description 1
- 239000008234 soft water Substances 0.000 description 1
- 238000009987 spinning Methods 0.000 description 1
- 239000000811 xylitol Substances 0.000 description 1
- HEBKCHPVOIAQTA-SCDXWVJYSA-N xylitol Chemical compound OC[C@H](O)[C@@H](O)[C@H](O)CO HEBKCHPVOIAQTA-SCDXWVJYSA-N 0.000 description 1
- 229960002675 xylitol Drugs 0.000 description 1
- 235000010447 xylitol Nutrition 0.000 description 1
Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C1/00—Pretreatment of the finely-divided materials before digesting
- D21C1/02—Pretreatment of the finely-divided materials before digesting with water or steam
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C3/00—Pulping cellulose-containing materials
- D21C3/02—Pulping cellulose-containing materials with inorganic bases or alkaline reacting compounds, e.g. sulfate processes
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C5/00—Other processes for obtaining cellulose, e.g. cooking cotton linters ; Processes characterised by the choice of cellulose-containing starting materials
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/10—Bleaching ; Apparatus therefor
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/18—De-watering; Elimination of cooking or pulp-treating liquors from the pulp
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
- D21F11/00—Processes for making continuous lengths of paper, or of cardboard, or of wet web for fibre board production, on paper-making machines
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Wood Science & Technology (AREA)
- Chemical & Material Sciences (AREA)
- Inorganic Chemistry (AREA)
- Paper (AREA)
Abstract
The invention discloses a preparation method of bamboo pulp for Lyocell fiber, which adopts steam heating and prehydrolysis liquid extraction processes to remove most hemicellulose in bamboo chips, greatly saves the production time of the bamboo pulp, solves the problems of large steam consumption, slow heating, long production period and high comprehensive cost of prehydrolysis liquid by heating, avoids the defects of nonuniform internal reaction and high pentosan content of products of bamboo chips by only using steam for prehydrolysis, improves the internal uniformity of the bamboo pulp, increases the accessibility of NMMO solvent, overcomes the bottleneck of quality and cost of Lyocell dissolving pulp produced by bamboo raw materials, and lays a foundation for improving the quality of Lyocell bamboo fiber. The invention also provides bamboo pulp prepared by the preparation method of the bamboo pulp for Lyocell fiber.
Description
Technical Field
The invention relates to a preparation method of bamboo pulp for Lyocell fiber and a product thereof.
Background
Lyocell fiber is one of green fiber in the 21 st century, and is prepared with wood pulp as main material and through refining, dissolving pulp directly into cellulose solution with NMMO as solvent and spinning.
In recent decades, development and development of bamboo Lyocell fibers have been developed, and bamboo pulp for Lyocell fibers requires better reaction uniformity, lower pentosan content and metal ion content than conventional viscose bamboo pulp.
At present, most of the factories producing bamboo pulp adopt a steam pre-hydrolysis method, the bamboo pulp obtained by the method has poor reaction uniformity and high pentosan content, and the preparation requirement of Lyocell fiber is difficult to meet; some manufacturers adopt a semi-liquid-phase pre-hydrolysis method, can consume less steam for heating and can achieve the purpose of liquid-phase hydrolysis, but the requirement of meeting the requirement that the circulating extraction amount still consumes more time for heating and the heat preservation time is longer, so that the whole production period is as long as 13-14 hours, and the production cost is high; the full liquid-phase pre-hydrolysis method has the advantages of large steam consumption, slow temperature rise and no effective method for treating the hydrolysis liquid, and the large-scale production is not realized at present.
Disclosure of Invention
In view of the defects of the prior art, the invention provides a preparation method of bamboo pulp for Lyocell fibers and a product thereof, so as to meet the preparation requirement of the bamboo Lyocell fibers.
The invention adopts a technical scheme that: provides a preparation method of bamboo pulp for Lyocell fiber, which comprises the following steps:
(1) preheating a material sheet: preheating bamboo chips in advance by adopting a steam pot filling mode when the bamboo chips are filled in a pot, introducing low-pressure steam from the top of the pot after a pot cover is covered after the pot is filled in the pot, and opening a liquid discharge valve at the bottom of the pot to raise the temperature in the pot to 110-130 ℃;
(2) heating the material sheet: introducing medium-pressure steam from the top and the bottom of the pot to raise the temperature in the pot to 160-170 ℃;
(3) liquid phase extraction and prehydrolysis: injecting the prehydrolysis liquid from the bottom of the pot, quickly raising the temperature in the pot to the required temperature, and preserving the heat at 165-175 ℃ for 30-120 min;
(4) alkali cooking: firstly, filling hot white liquid into a pot to neutralize to be alkaline; then hot night is injected into the pot to replace the neutralizing liquid; then filling hot white liquid into the pot, heating to 160-175 ℃, preserving heat for 30-150 min, and then putting the pot to obtain slurry;
(5) bleaching: passing the slurry through O-D 0 -E OP -D 1 Bleaching to obtain bleached pulp;
(6) acid treatment and washing: carrying out acid treatment and washing procedures on the bleached pulp to obtain bleached bamboo pulp;
(7) manufacturing a pulp board: the bleached bamboo pulp is manufactured by a pulp machine to obtain the bamboo pulp, and the net surfing concentration of the bleached bamboo pulp is 1.3-2.0%.
As an improvement to the above scheme, the prehydrolysis liquid is a mixed liquid of hot water and an acidic catalytic assistant, and the liquid ratio of the prehydrolysis liquid is 3.0: 1-4.5: 1, the temperature is 165-170 ℃.
As an improvement to the above scheme, the liquid ratio of the prehydrolysis liquid is 4: 1, the acidic catalytic assistant is at least one of formic acid, acetic acid and propionic acid, and the dosage of the acidic catalytic assistant is 0.1-2% of the weight of oven-dried bamboo chips.
As an improvement to the scheme, in the step (3), a steam heater is arranged outside the pot body, and medium-pressure steam is introduced into the steam heater; and circulating the prehydrolysis liquid through a circulating pump.
As an improvement of the scheme, after the liquid phase extraction prehydrolysis is completed, extracting the hydrolysate from the bottom of the pot to a liquid storage tank, recycling the hydrolysate in the liquid storage tank to the step (3) as the prehydrolysis liquid, wherein the recycling amount of the hydrolysate is 30% -100% of the total amount of the prehydrolysis liquid required by each pot of bamboo chips.
The improvement of the scheme is that the recycling amount of the hydrolysate is 50% -80% of the total liquid amount of the prehydrolysis liquid required by each pot of bamboo chips, fresh prehydrolysis liquid at the temperature of 150-170 ℃ is supplemented into the pot while the hydrolysate is recycled, and the supplementing amount of the fresh prehydrolysis liquid is 20% -50% of the total liquid amount of the prehydrolysis liquid required by each pot of bamboo chips.
As an improvement to the scheme, after the step (3) is completed, the hydrolysis liquid is extracted from the bottom of the pot, and simultaneously medium-pressure steam is introduced from the top of the pot to steam-wash the bamboo chips in the pot.
In step (1), the drain valve includes a steam-water separator.
As an improvement to the scheme, a chelating agent is added into the bleaching pulp in the acid treatment stage in the step (6), the chelating temperature is 40-75 ℃, the use amount of hydrochloric acid is 0.5-1.5%, and the chelating time is 1-1.5 h; the chelating agent comprises at least one of DTPA (diethylenetriamine pentaacetic acid), EDTA (ethylene diamine tetraacetic acid), NTA (nitrilotriacetic acid) or sodium hexametaphosphate.
The invention adopts a technical scheme that: provides a bamboo pulp which is prepared by the preparation method of the bamboo pulp for Lyocell fiber.
Different from the prior art, the preparation method of the bamboo pulp for the Lyocell fibers provided by the invention adopts the processes of steam heating and prehydrolysis liquid extraction to remove most of hemicellulose in the bamboo chips, greatly saves the production time of the bamboo pulp, solves the problems of large steam consumption, slow heating, long production period and high comprehensive cost of prehydrolysis liquid depending on heating, avoids the defects of nonuniform reaction and high pentosan content of products in the bamboo chips by means of pure steam prehydrolysis, improves the internal uniformity of the bamboo pulp, increases the accessibility of an NMMO solvent, overcomes the bottlenecks of quality and cost of Lyocell dissolving pulp produced by bamboo raw materials, and lays a foundation for improving the quality of the Lyocell bamboo fibers. The invention also provides bamboo pulp prepared by the preparation method of the bamboo pulp for Lyocell fiber.
Detailed Description
The invention provides a preparation method of bamboo pulp for Lyocell fiber, which comprises the following steps:
(1) preheating a material sheet:
the bamboo chips are put into the pot by adopting low-pressure steam, and the low-pressure steam is introduced from the bottom of the pot to preheat the bamboo chips when the pot is put into the pot. After the pot is filled, the pot cover is covered, low-pressure steam is introduced from the top of the pot, a drain valve at the bottom of the pot is opened, and the temperature in the pot rises to 110-130 ℃.
Steam is fed from the top of the pot in the initial heating stage of the bamboo chips, so that impurities in the pot can be discharged from the bottom of the pot, and the cleanliness of the product is improved.
Further, the drain valve comprises a steam-water separator.
(2) Heating the material sheet: introducing medium-pressure steam from the top and the bottom of the pot to quickly raise the temperature in the pot to 160-170 ℃.
In the step, the bamboo chips are heated to 160-170 ℃ by medium-pressure steam, conditions are created for the liquid phase extraction and prehydrolysis of the later section, and the heating time is shortened.
The preheating and heating stages of the bamboo chips before the liquid phase extraction prehydrolysis all adopt steam as a medium, so that the heating speed can be obviously increased, the prehydrolysis time of the bamboo chips is shortened, and the production efficiency of the bamboo pulp is further improved.
(3) Liquid phase extraction and prehydrolysis: injecting the pre-hydrolysis liquid from the bottom of the pot, quickly raising the temperature in the pot to the required temperature, and preserving the heat at 165-175 ℃ for 30-120 min;
the steam replaced in the boiler exchanges heat with cold water to recover heat.
In the preparation method of the bamboo pulp, the prehydrolysis of the bamboo chips is mainly performed by liquid phase extraction prehydrolysis in the step, so that the prehydrolysis uniformity of the bamboo chips is guaranteed, and conditions are provided for hydrolysis and dissolution of lignin and hemicellulose.
The steam preheating and temperature rising are combined with the liquid phase extraction and prehydrolysis, most of hemicellulose in the bamboo chips is removed, the problems of large steam consumption, slow temperature rising, long production period and high comprehensive cost of prehydrolysis liquid by temperature rising are solved, the defects of uneven internal reaction and higher pentosan content of the product of bamboo chips which are subjected to pure steam prehydrolysis are avoided, the internal uniformity of the bamboo pulp is improved, the accessibility of an NMMO solvent is increased, the bottleneck of quality and cost of Lyocell dissolving pulp produced by bamboo raw materials is overcome, and a foundation is laid for the quality improvement of Lyocell bamboo fibers.
Further, the prehydrolysis liquid is a mixed liquid of hot water and an acidic catalytic auxiliary agent, and the liquid ratio of the prehydrolysis liquid is 3.0: 1-4.5: 1, the temperature is 165-170 ℃.
After the steam is heated to the temperature required by the process, high-temperature prehydrolysis liquid is injected into the pot, so that the temperature and the pH value in the pot quickly reach the prehydrolysis requirement.
Further, the liquid ratio of the prehydrolysis liquid is 4: 1, the acidic catalytic assistant is at least one of formic acid, acetic acid and propionic acid, and the dosage of the acidic catalytic assistant is 0.1-2% of the weight of oven-dried bamboo chips.
Preferably, the liquid ratio of the prehydrolysis liquid is 3.5: 1.
the liquid ratio in this application refers to the ratio of the total liquid volume of the prehydrolysis liquid (L or m3) to the weight of the oven dried bamboo chips (kg or t).
Further, the heating is specifically that a steam heater is arranged outside the pot body, medium-pressure steam is introduced into the steam heater to heat the pot body, and the prehydrolysis liquid is circulated by a circulating pump to heat and preserve the temperature of the bamboo chips.
In the application, after the step of liquid phase extraction and prehydrolysis is completed, the hydrolysate is extracted from the bottom of the pot to the liquid storage tank, the hydrolysate in the liquid storage tank is recycled to the liquid phase extraction and prehydrolysis of the next pot to be used as the prehydrolysis solution, and the recycling amount of the hydrolysate is 30% -100% of the total amount of the prehydrolysis solution required by each pot of bamboo chips.
Due to the recycling of the hydrolysate, most of heat energy is recovered, and the consumption of steam required by heating is reduced. The direct recycling of the high-temperature hydrolysate greatly saves energy consumption and effectively accelerates the hydrolysis progress of the bamboo chips.
Furthermore, the recycling amount of the hydrolysate is 50% -80% of the total liquid amount of the prehydrolysis liquid required by each pot of bamboo chips, preferably, the recycling amount of the hydrolysate is 60% -70% of the total liquid amount of the prehydrolysis liquid required by each pot of bamboo chips, so that the recycling of the hydrolysate is ensured without causing negative influence on the product quality while the heat energy and the organic acid required by the prehydrolysis are fully recycled.
And (3) while recycling the hydrolysate, supplementing fresh prehydrolysis liquid at the temperature of 150-170 ℃ into the pot, wherein the supplement amount of the fresh prehydrolysis liquid is 20% -50% of the total liquid amount of the prehydrolysis liquid required by each pot of bamboo chips.
The method adopts the liquid phase extraction prehydrolysis mode of the reuse hydrolysate, greatly improves the hydrolysis efficiency of the bamboo chips, saves energy consumption, has large liquid ratio of the prehydrolysis of the liquid phase extraction, can realize the complete immersion of the bamboo chips by the hydrolysate, ensures the uniformity of the hydrolysis reaction of the bamboo chips, and improves the uniformity of the prepared bamboo pulp.
In the application, after the liquid phase extraction prehydrolysis step is completed, when hydrolysate is extracted from the bottom of the pot, medium-pressure steam is introduced from the top of the pot to steam wash the bamboo chips in the pot so as to inhibit further condensation of lignin in the bamboo chips in the pot, so that the lignin is conveniently removed in later-stage alkaline cooking and bleaching, and the production time is shortened.
In the application, carry out the biomass refining to unnecessary hydrolysate after through the heat exchange cooling, the biomass refining specifically is to extract the high added value products such as furfural, ethanol, oligosaccharide, xylose or xylitol of polysaccharide preparation in the hydrolysate.
(4) Alkali cooking: after the liquid phase extraction prehydrolysis is finished, hot white liquid with 20% of alkali dosage is filled into the pot to neutralize to be alkaline; hot night is injected into the pot to replace the neutralizing liquid; and (3) after the neutralization solution is completely replaced out of the pot, continuously filling hot white liquid with the alkali dosage of 80% into the pot, heating to 160-175 ℃, keeping the temperature for 30-150 min, and then putting the pot to obtain the slurry.
(5) Bleaching: passing the slurry through O-D 0 -E OP -D 1 Bleaching to obtain bleached pulp.
In this step, at D 0 And in the section, a chelating agent is added into the pulp for bleaching treatment, and the pulp is subjected to ash removal and iron removal (to remove ash and iron in the bleached pulp), so that the product cleanliness is improved, and the metal ion content is reduced. Wherein the bleaching temperature is 50-60 ℃, the pH value is 2-3, and the bleaching time is 2-3 h.
The chelating agent comprises at least one of DTPA (diethylenetriamine pentaacetic acid), EDTA (ethylene diamine tetraacetic acid), NTA (nitrilotriacetic acid) or sodium hexametaphosphate.
(6) Acid treatment and washing: and (3) carrying out acid treatment and washing procedures on the bleached pulp to obtain the bleached bamboo pulp.
In the acid treatment process, the use amount of hydrochloric acid is 0.5-1.5%, and further, a chelating agent is introduced into the acid treatment process to further remove ash and iron in the bleaching pulp, wherein the acid treatment temperature is 40-75 ℃, preferably 50-70 ℃, more preferably 60-70 ℃, and the acid treatment time is 1-1.5 h.
The chelating agent comprises at least one of DTPA (diethylenetriamine pentaacetic acid), EDTA (ethylene diamine tetraacetic acid), NTA (nitrilotriacetic acid) or sodium hexametaphosphate.
In the washing procedure, soft water is adopted to wash the slurry after acid treatment to be neutral for pulp making.
(7) Manufacturing pulp sheets: the bleached bamboo pulp is manufactured by a pulp machine to obtain the bamboo pulp, and the net feeding concentration of the bleached bamboo pulp is 1.3-2.0%.
Furthermore, the net-loading concentration of the bleached bamboo pulp is 1.3-1.8%, and more preferably 1.5-1.6%, so as to ensure that the forming evenness of the pulp sheet is good.
The present invention will be described in further detail with reference to examples. It is to be noted that the following examples are only illustrative of the present invention, and do not limit the scope of the present invention. Similarly, the following examples are only some examples but not all examples of the present application, and all other examples obtained by those skilled in the art without any inventive work are within the scope of the present invention.
The first embodiment is as follows:
this example provides a method for preparing bamboo pulp, comprising the following steps:
(1) preheating a material sheet:
taking 100% Sasa Arguta as raw material, preheating bamboo chips by steam in a pot, introducing low-pressure steam from the top of the pot after the pot is filled, and opening a drain valve at the bottom of the pot until the temperature in the pot rises to 120 deg.C, which takes 80 min.
(2) Heating the material sheet:
introducing medium-pressure steam from the top of the boiler, and heating for 60min to 165 ℃.
(3) Liquid phase extraction and prehydrolysis:
injecting 170 ℃ reuse hydrolysate from the bottom of the pot to replace steam, consuming 30min, simultaneously supplementing 50% of 150 ℃ hot water and 0.5% of acetic acid in the total amount of the prehydrolysis liquid, heating the material sheet in the pot, raising the temperature to 170 ℃ after 40min to perform liquid phase extraction prehydrolysis, discharging the hydrolysate after keeping the temperature for 60min, simultaneously introducing medium-pressure steam from the top of the pot to perform steam washing on the bamboo sheets in the pot, and discharging the hydrolysis liquid in the pot after 30 min.
(4) Alkali cooking:
and starting a hot white liquor displacement pump to fill white liquor with 20% of alkali dosage into the pot to neutralize the bamboo chips in the pot to be alkaline, then injecting hot black liquor to fill the pot with alkali liquor, continuing to supplement white liquor with 80% of alkali dosage after the neutralization liquor is completely displaced out of the pot, consuming 40min totally, then heating to 170 ℃, preserving heat for 60min, finally recovering for 30min, and placing in the pot for 20min to obtain the pulp.
The whole preheating, heating, prehydrolysis and soda boiling cycle is 450 min.
(5) Bleaching: passing the slurry through O-D 0 -E OP -D 1 Bleaching to obtain bleached pulp.
(6) Acid treatment and washing: and (3) carrying out acid treatment and washing procedures on the bleached pulp to obtain the bleached bamboo pulp.
In the acid treatment process, the amount of the hydrochloric acid is 1%, and further, a chelating agent is introduced in the acid treatment process to remove ash and iron in the bleaching pulp, wherein the acid treatment temperature is 60 ℃, and the acid treatment time is 1 h.
(7) Manufacturing pulp sheets: the bleached bamboo pulp is manufactured by a pulp machine to obtain bamboo pulp, and the net surfing concentration of the bleached bamboo pulp is 1.5%.
The yield of the bamboo pulp prepared by the preparation method of the embodiment is 30.5%, the whiteness is 86.8% ISO, the methyl cellulose is 95.3%, the pentosan is 2.95%, the alkali absorption value is 540%, the iron content is 10ppm, the ash content is 0.05%, the polymerization Degree (DP)520 and the resin content are0.08%, 10.5% water, 705g/m 2 。
Example two:
this example provides a method for preparing bamboo pulp, comprising the following steps:
(1) preheating a material sheet:
taking 100% Sasa Arguta as raw material, preheating bamboo chips by steam in a pot, introducing low-pressure steam from the top of the pot after the pot is filled, and opening a drain valve at the bottom of the pot until the temperature in the pot rises to 115 deg.C, which takes 80 min.
(2) Heating the material sheet:
introducing medium-pressure steam from the top of the boiler, and heating for 60min to 165 ℃.
(3) Liquid phase extraction and prehydrolysis:
injecting 170 ℃ reuse hydrolysate from the bottom of the pot to replace steam, consuming 30min, simultaneously supplementing 30% hot water at 150 ℃ and 1.0% acetic acid in the total amount of the prehydrolysis liquid, heating the material sheets in the pot, raising the temperature to 172 ℃ after 30min to perform liquid phase extraction prehydrolysis, discharging the hydrolysate after keeping the temperature for 40min, simultaneously introducing medium-pressure steam from the top of the pot to perform steam washing on the bamboo sheets in the pot, and discharging the hydrolysate in the pot after 30 min.
(4) Alkali cooking:
and starting a hot white liquor displacement pump to fill white liquor with 20% of alkali dosage into the pot to neutralize the bamboo chips in the pot to be alkaline, then injecting hot black liquor to fill the pot with alkali liquor, continuing to supplement white liquor with 80% of alkali dosage after the neutralization liquor is completely displaced out of the pot, consuming 40min totally, then heating to 170 ℃, preserving heat for 60min, finally recovering for 30min, and placing in the pot for 20min to obtain the pulp.
The whole cycle of preheating, temperature rising, prehydrolysis and alkaline cooking is 420min in total.
(5) Bleaching: passing the slurry through O-D 0 -E OP -D 1 Bleaching to obtain bleached pulp.
(6) Acid treatment and washing: and (3) carrying out acid treatment and washing procedures on the bleached pulp to obtain the bleached bamboo pulp.
In the acid treatment process, the amount of hydrochloric acid is 1%, and further, a chelating agent is introduced in the acid treatment process to remove ash and iron in the bleaching pulp, wherein the acid treatment temperature is 70 ℃, and the acid treatment time is 1.5 h.
(7) Manufacturing pulp sheets: the bleached bamboo pulp is manufactured by a pulp machine to obtain the bamboo pulp, and the net feeding concentration of the bleached bamboo pulp is 1.5%.
The bamboo pulp obtained by the method for producing bamboo pulp of this example had a yield of 29.5%, a whiteness degree of 87.5% ISO, a methyl cellulose of 95.5%, a pentosan of 2.70%, an alkali absorption value of 514%, an iron content of 6.5ppm, an ash content of 0.07%, a Degree of Polymerization (DP)
505, resin content 0.05%, moisture 9.2%, basis weight 685g/m 2 。
Example three:
this example provides a method for preparing bamboo pulp, comprising the following steps:
(1) preheating a material sheet:
taking 50% Sasa albo-marginata, 30% Mianzhu and 20% Ma bamboo as raw materials, preheating bamboo chips by steam in a pot, introducing low-pressure steam from the top of the pot after the pot is filled, and opening a drain valve at the bottom of the pot until the temperature in the pot rises to 110 ℃, and taking 80 min.
(2) Heating the material sheet:
introducing medium-pressure steam from the top of the boiler, and heating to 170 ℃ for 90 min.
(3) Liquid phase extraction and prehydrolysis:
injecting 170 ℃ reuse hydrolysate from the bottom of the pot to replace steam, consuming 30min, simultaneously supplementing 40% of 170 ℃ hot water and 0.5% of acetic acid in the total amount of the prehydrolysis liquid, heating the material sheet in the pot, raising the temperature to 173 ℃ after 30min to perform liquid phase extraction prehydrolysis, discharging the hydrolysate after heat preservation for 70min, simultaneously introducing medium-pressure steam from the top of the pot to perform steam washing on the bamboo sheets in the pot, and discharging the hydrolysate in the pot after 30 min.
(4) Alkali cooking:
and starting a hot white liquor displacement pump to fill white liquor with 20% of alkali dosage into the pot to neutralize the bamboo chips in the pot to be alkaline, then injecting hot black liquor to fill the pot with alkali liquor, continuing to supplement white liquor with 80% of alkali dosage after the neutralization liquor is completely displaced out of the pot, consuming 40min totally, then heating to 170 ℃, preserving heat for 50min, finally recovering for 30min, and placing in the pot for 20min to obtain the pulp.
The whole preheating, temperature rising, prehydrolysis and alkaline cooking cycle is 470 min.
(5) Bleaching: passing the slurry through O-D 0 -E OP -D 1 Bleaching to obtain bleached pulp.
(6) Acid treatment and washing: and (3) carrying out acid treatment and washing procedures on the bleached pulp to obtain the bleached bamboo pulp.
In the acid treatment process, the amount of hydrochloric acid was 0.5%, and further, a chelating agent was introduced in the acid treatment process to remove ash and iron components from the bleaching slurry, wherein the acid treatment temperature was 50 ℃ and the acid treatment time was 1 hour.
(7) Manufacturing pulp sheets: the bleached bamboo pulp is manufactured by a pulp machine to obtain the bamboo pulp, and the net feeding concentration of the bleached bamboo pulp is 1.5%.
The yield of the bamboo pulp prepared by the method for preparing the bamboo pulp of the embodiment is 31.0%, the whiteness is 86.5% ISO, the methyl cellulose is 94.5%, the pentosan is 2.65%, the alkali absorption value is 535%, the iron content is 11.5ppm, the ash content is 0.09%, the polymerization Degree (DP)530, the resin content is 0.1%, the water content is 9.8%, and the quantitative content is 720g/m 2 。
Example four:
this example provides a method for preparing bamboo pulp, comprising the following steps:
(1) preheating a material sheet:
taking 50% Sasa albo-marginata, 30% Mianzhu and 20% Ma bamboo as raw materials, preheating bamboo chips by steam in a pot, introducing low-pressure steam from the top of the pot after the pot is filled, and opening a drain valve at the bottom of the pot until the temperature in the pot rises to 130 ℃, and taking 80 min.
(2) Heating the material sheet:
introducing medium-pressure steam from the top of the boiler, and heating to 160 ℃ for 60 min.
(3) Liquid phase extraction and prehydrolysis:
injecting 170 ℃ reuse hydrolysate from the bottom of the pot to replace steam, consuming 30min, simultaneously supplementing 60% hot water at 150 ℃ and 0.3% acetic acid in the total amount of the prehydrolysis liquid, heating the material sheet in the pot, raising the temperature to 169 ℃ after 30min to perform liquid phase extraction prehydrolysis, discharging the hydrolysate after heat preservation for 50min, simultaneously introducing medium-pressure steam from the top of the pot to perform steam washing on the bamboo sheets in the pot, and discharging the hydrolysate in the pot after 30 min.
(4) Alkali cooking:
and starting a hot white liquor displacement pump to fill white liquor with 20% of alkali dosage into the pot to neutralize the bamboo chips in the pot to be alkaline, then injecting hot black liquor to fill the pot with alkali liquor, continuing to supplement white liquor with 80% of alkali dosage after the neutralization liquor is completely displaced out of the pot, consuming 40min totally, then heating to 170 ℃, preserving heat for 60min, finally recovering for 30min, and placing in the pot for 20min to obtain the pulp.
The whole preheating, heating, prehydrolysis and soda boiling cycle is 430min in total.
(5) Bleaching: passing the slurry through O-D 0 -E OP -D 1 Bleaching to obtain bleached pulp.
(6) Acid treatment and washing: and (3) carrying out acid treatment and washing procedures on the bleaching pulp to obtain the bleached bamboo pulp.
In the acid treatment process, the amount of hydrochloric acid is 1%, and further, a chelating agent is introduced in the acid treatment process to remove ash and iron in the bleaching pulp, wherein the acid treatment temperature is 65 ℃, and the acid treatment time is 80 min.
(7) Manufacturing pulp sheets: the bleached bamboo pulp is manufactured by a pulp machine to obtain bamboo pulp, and the net surfing concentration of the bleached bamboo pulp is 1.5%.
The yield of the bamboo pulp prepared by the method for preparing the bamboo pulp of the embodiment is 31.5%, the whiteness is 87.5% ISO, the methyl cellulose is 96.0%, the pentosan is 3.2%, the alkali absorption value is 540%, the iron content is 9.0ppm, the ash content is 0.03%, the polymerization Degree (DP) is 550, the resin content is 0.06%, the water content is 10.3%, and the quantitative content is 690g/m 2 。
Comparative example one:
the comparative example provides a preparation method of bamboo pulp, comprising the following steps:
(1) preheating a material sheet:
taking 50% Sagittaria sagittifolia, 30% Mianzhu and 20% Ma bamboo as raw materials, filling steam into a pot to preheat bamboo chips, introducing low-pressure steam from the top of the pot after the pot is filled, opening a drain valve at the bottom of the pot until the temperature in the pot rises to 120 ℃, and taking 80 min.
(2) Steam prehydrolysis:
introducing medium-pressure steam from the top of the boiler, heating to 170 ℃ for 90min, and keeping the temperature for 90 min.
(3) Alkali cooking:
and starting a hot white liquor displacement pump to fill white liquor with 20% of alkali dosage into the pot to neutralize the bamboo chips in the pot to be alkaline, then injecting hot black liquor to fill the pot with alkali liquor, continuing to supplement white liquor with 80% of alkali dosage after the neutralization liquor is completely displaced out of the pot, consuming 40min totally, then heating to 170 ℃, preserving heat for 60min, finally recovering for 30min, and placing in the pot for 20min to obtain the pulp.
The total preheating, prehydrolysis and soda boiling cycle is 410 min.
(4) Bleaching: passing the slurry through O-D 0 -E OP -D 1 Bleaching to obtain bleached pulp.
(5) Acid treatment and washing: and (3) carrying out acid treatment and washing procedures on the bleached pulp to obtain the bleached bamboo pulp.
In the acid treatment process, the use amount of hydrochloric acid is 1%, and a chelation process is not introduced.
(6) Manufacturing pulp sheets: the bleached bamboo pulp is manufactured by a pulp machine to obtain bamboo pulp, and the net surfing concentration of the bleached bamboo pulp is 1.5%.
The bamboo pulp obtained by the method for preparing the bamboo pulp of the comparative example has the yield of 32.0 percent, the whiteness of 86.5 percent ISO, 94.5 percent methyl cellulose, 4.5 percent pentosan, the alkali absorption value of 480 percent, the iron content of 25.0ppm, the ash content of 0.1 percent, the polymerization Degree (DP) of 530, the resin content of 0.05 percent, the water content of 10.0 percent and the quantitative quantity of 695g/m 2 。
Comparative example two:
(1) preheating a material sheet:
taking 100% Sasa Arguta as raw material, preheating bamboo chips by steam in a pot, introducing low-pressure steam from the top of the pot after the pot is filled, and opening a drain valve at the bottom of the pot until the temperature in the pot rises to 125 deg.C, which takes 80 min.
(2) Liquid-phase prehydrolysis:
after the pot is filled, adding hot water for 30min to meet the circulation, wherein the liquid ratio is 2.5: 1, heating the pot body, heating to 170 ℃ after 160min for liquid phase prehydrolysis, keeping the temperature for 120min, then discharging hydrolysate, and discharging hydrolysate in the pot for 40 min.
(3) Alkali cooking:
starting a hot white liquor displacement pump to fill white liquor with 20% of alkali dosage into the pot to neutralize the bamboo chips in the pot to be alkaline, then injecting hot black liquor to fill the pot with alkali liquor, continuing to supplement white liquor with 80% of alkali dosage after the neutralization liquor is completely displaced out of the pot, consuming 40min totally, then heating to 170 ℃, preserving the temperature for 90min, finally recovering for 30min, and placing the pot for 20min to obtain the pulp.
The total prehydrolysis and soda cooking cycle amounted to 610 min.
(4) Bleaching: passing the slurry through O-D 0 -E OP -D 1 Bleaching to obtain bleached pulp.
(5) Acid treatment and washing: and (3) carrying out acid treatment and washing procedures on the bleached pulp to obtain the bleached bamboo pulp.
In the acid treatment process, the amount of hydrochloric acid is 1%, and a chelation process is not introduced.
(6) Manufacturing pulp sheets: the bleached bamboo pulp is manufactured by a pulp machine to obtain bamboo pulp, and the net surfing concentration of the bleached bamboo pulp is 1.5%.
The bamboo pulp obtained by the method for preparing the bamboo pulp of the comparative example has the yield of 28.9 percent, the whiteness of 87.0 percent ISO, 94.8 percent methyl cellulose, 2.85 percent pentosan, the alkali absorption value of 510 percent, 19.0ppm of iron content, 0.09 percent of ash content, 450 percent polymerization Degree (DP), 0.05 percent of resin content, 9.0 percent of water content and 685g/m quantitative 2 。
Of the two comparative examples described above, comparative example one used only steam as the prehydrolysis medium and comparative example 2 used only hot water as the prehydrolysis medium.
Comparing the above four examples with the two comparative examples, it is clear that the first comparative example has fast hydrolysis temperature rise and relatively short production period, but the prepared bamboo pulp has high pentosan content, low alkali absorption value and non-ideal bamboo pulp reaction uniformity; the comparative example II has long temperature rise time, large steam consumption, long production period and high comprehensive cost.
The embodiment of the application adopts steam preheating and temperature rising combined with liquid phase extraction for prehydrolysis, removes most hemicellulose in the bamboo chips, solves the problems of large steam consumption, slow temperature rising, long production period and high comprehensive cost of prehydrolysis liquid by means of temperature rising, avoids the defects of uneven internal reaction and higher pentosan content of a product of bamboo chips by means of simple steam prehydrolysis, improves the internal uniformity of bamboo pulp, increases the accessibility of an NMMO solvent, overcomes the bottleneck of quality and cost of Lyocell dissolving pulp produced by bamboo raw materials, and lays a foundation for quality improvement of Lyocell bamboo fibers.
The application also provides the bamboo pulp prepared by the preparation method of the bamboo pulp, the bamboo pulp has low pentosan content, high reaction uniformity and low ash content and iron content, improves the accessibility of the NMMO solvent, and can meet the preparation requirement of the bamboo Lyocell fiber.
The above description is only an example of the present application and is not intended to limit the scope of the present application, and all modifications of equivalent structures and equivalent processes, which are made by the present specification and directly or indirectly applied to other related technical fields, are intended to be included within the scope of the present application.
Claims (10)
1. A preparation method of bamboo pulp for Lyocell fiber is characterized by comprising the following steps:
(1) preheating a material sheet: preheating bamboo chips in advance by adopting a steam pot filling mode when the bamboo chips are filled in a pot, introducing low-pressure steam from the top of the pot after a pot cover is covered after the pot is filled in the pot, and opening a liquid discharge valve at the bottom of the pot to raise the temperature in the pot to 110-130 ℃;
(2) heating the material sheet: introducing medium-pressure steam from the top and the bottom of the pot to raise the temperature in the pot to 160-170 ℃;
(3) liquid phase extraction and prehydrolysis: injecting the prehydrolysis liquid from the bottom of the pot, raising the temperature in the pot to the required temperature, and preserving the heat at 165-175 ℃ for 30-120 min;
(4) alkali cooking: firstly, filling hot white liquid into a pot to neutralize to be alkaline; then hot night is injected into the pot to replace the neutralizing liquid; then filling hot white liquid into the pot, heating to 160-175 ℃, keeping the temperature for 30-150 min, and then putting the pot to obtain slurry;
(5) bleaching: passing the slurry through O-D 0 -E OP -D 1 Bleaching to obtain bleached pulp;
(6) acid treatment and washing: carrying out acid treatment and washing procedures on the bleached pulp to obtain bleached bamboo pulp;
(7) manufacturing pulp sheets: the bleached bamboo pulp is manufactured by a pulp machine to obtain the bamboo pulp, and the net surfing concentration of the bleached bamboo pulp is 1.3-2.0%.
2. The method for preparing bamboo pulp for Lyocell fiber according to claim 1, wherein said prehydrolysis liquid is a mixture of hot water and acidic catalytic assistant, and the liquid ratio of the prehydrolysis liquid is 3.0: 1-4.5: 1, the temperature is 165-172 ℃. The temperature of the hot white liquid is 110-130 ℃.
3. The method for preparing bamboo pulp for Lyocell fiber according to claim 2, wherein the liquid ratio of said prehydrolysis liquid is 4: 1, the acidic catalytic assistant is at least one of formic acid, acetic acid and propionic acid, and the dosage of the acidic catalytic assistant is 0.1-2% of the weight of oven-dried bamboo chips.
4. The preparation method of the bamboo pulp for the Lyocell fiber according to claim 1, wherein in the step (3), a steam heater is arranged outside the pot body, and medium-pressure steam is introduced into the steam heater; the prehydrolysis liquid is circulated by a circulating pump.
5. The method for preparing the bamboo pulp for the Lyocell fibers according to claim 1, wherein after the liquid phase extraction prehydrolysis is completed, the hydrolysate is extracted from the bottom of the pot and sent to the liquid storage tank, the hydrolysate in the liquid storage tank is recycled to the step (3) to be used as the prehydrolysis liquid, and the recycling amount of the hydrolysate is 30-100% of the total amount of the prehydrolysis liquid required by each pot of bamboo chips.
6. The preparation method of the bamboo pulp for the Lyocell fiber according to claim 5, wherein the recycling amount of the hydrolysate is 50% -80% of the total amount of the prehydrolysis liquid required by each pot of bamboo chips, the hydrolysate is recycled, and meanwhile, fresh prehydrolysis liquid with the temperature of 150-170 ℃ is supplemented into the pot, and the supplementing amount of the fresh prehydrolysis liquid is 20% -50% of the total amount of the prehydrolysis liquid required by each pot of bamboo chips.
7. The method of claim 5, wherein the bamboo chips are steam washed by introducing medium pressure steam from the top of the pot while extracting the hydrolysate from the bottom of the pot after the step (3).
8. The method for preparing bamboo pulp for Lyocell fiber according to claim 1, wherein in the step (1), said drain valve comprises a steam-water separator.
9. The method for preparing the bamboo pulp for the Lyocell fiber according to claim 1, wherein a chelating agent is added into the bleached pulp in the acid treatment stage of the step (6), wherein the chelating temperature is 40-75 ℃, the amount of hydrochloric acid is 0.5-1.5%, and the chelating time is 1-1.5 h; the chelating agent comprises at least one of DTPA (diethylenetriamine pentaacetic acid), EDTA (ethylene diamine tetraacetic acid), NTA (nitrilotriacetic acid) or sodium hexametaphosphate.
10. A bamboo pulp, characterized by, made from any one of claim 1-9 Lyocell fiber used in the bamboo pulp preparation method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210768213.3A CN114960248A (en) | 2022-06-30 | 2022-06-30 | Preparation method of bamboo pulp for Lyocell fiber and product thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210768213.3A CN114960248A (en) | 2022-06-30 | 2022-06-30 | Preparation method of bamboo pulp for Lyocell fiber and product thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114960248A true CN114960248A (en) | 2022-08-30 |
Family
ID=82967416
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210768213.3A Pending CN114960248A (en) | 2022-06-30 | 2022-06-30 | Preparation method of bamboo pulp for Lyocell fiber and product thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114960248A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116145457A (en) * | 2022-11-24 | 2023-05-23 | 泰盛科技（集团）股份有限公司 | Preparation method of bleached bamboo pulp |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2004005608A1 (en) * | 2002-07-02 | 2004-01-15 | Andritz, Inc. | Solvent pulping of biomass |
| CN102182086A (en) * | 2011-03-25 | 2011-09-14 | 四川永丰纸业股份有限公司 | Method for preparing bamboo pulp by full-liquid-phase prehydrolysis sulfate displacement cooking process |
| CN108455754A (en) * | 2018-02-24 | 2018-08-28 | 北京林业大学 | A kind of method that hydro-thermal acidolysis is used to handle plant material pre-hydrolyzed solution |
| CN112813713A (en) * | 2021-01-07 | 2021-05-18 | 杭州融凯盛科技有限公司 | Preparation method of special pulp for producing lyocell fibers from bamboo willows |
| CN113882181A (en) * | 2021-09-03 | 2022-01-04 | 四川天竹竹资源开发有限公司 | Lyocell fiber bamboo pulp and preparation method thereof |
| CN114232378A (en) * | 2021-12-29 | 2022-03-25 | 泰盛科技（集团）股份有限公司 | Bamboo pulp preparation method and bamboo pulp |
-
2022
- 2022-06-30 CN CN202210768213.3A patent/CN114960248A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2004005608A1 (en) * | 2002-07-02 | 2004-01-15 | Andritz, Inc. | Solvent pulping of biomass |
| CN102182086A (en) * | 2011-03-25 | 2011-09-14 | 四川永丰纸业股份有限公司 | Method for preparing bamboo pulp by full-liquid-phase prehydrolysis sulfate displacement cooking process |
| CN108455754A (en) * | 2018-02-24 | 2018-08-28 | 北京林业大学 | A kind of method that hydro-thermal acidolysis is used to handle plant material pre-hydrolyzed solution |
| CN112813713A (en) * | 2021-01-07 | 2021-05-18 | 杭州融凯盛科技有限公司 | Preparation method of special pulp for producing lyocell fibers from bamboo willows |
| CN113882181A (en) * | 2021-09-03 | 2022-01-04 | 四川天竹竹资源开发有限公司 | Lyocell fiber bamboo pulp and preparation method thereof |
| CN114232378A (en) * | 2021-12-29 | 2022-03-25 | 泰盛科技（集团）股份有限公司 | Bamboo pulp preparation method and bamboo pulp |
Non-Patent Citations (1)
| Title |
|---|
| 詹怀宇等: "《制浆技术》", 中国轻工业出版社, pages: 58 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116145457A (en) * | 2022-11-24 | 2023-05-23 | 泰盛科技（集团）股份有限公司 | Preparation method of bleached bamboo pulp |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA2641686C (en) | Method for recovering hydrolysis products | |
| CA2761757C (en) | Method for producing pulp | |
| CN114232378B (en) | Bamboo pulp preparation method and bamboo pulp | |
| CA2837277C (en) | Compact process for producing prehydrolyzed pulp | |
| CN102888772B (en) | Method for preparing bamboo pulp by replacing cooking sulfate with steaming sulfate | |
| EP3018251B1 (en) | Method for recovering hydrolysate in a prehydrolysis sulfate cooking process for producing pulp | |
| CN114960248A (en) | Preparation method of bamboo pulp for Lyocell fiber and product thereof | |
| CN102312386B (en) | Boiling method for preparing dissolving pulp by use of bleached chemical paper pulp | |
| CN110904710A (en) | Bamboo pulp preparation process | |
| CN102251423B (en) | Continuous displacement and digestion process for dissolving pulp | |
| FI120361B (en) | Batch cooking process for the production of kraft pulp | |
| JP6196022B2 (en) | Method for producing dissolved kraft pulp | |
| CN220266173U (en) | Slurry digestion system | |
| CN115726210B (en) | Production process of low-polymerization-degree cotton pulp for ultra-low-viscosity hydroxyethyl cellulose | |
| CN108396580A (en) | A method of it improving black liquor and is passivated evaporation efficiency | |
| CN116145457A (en) | Preparation method of bleached bamboo pulp | |
| CN114096711B (en) | High alpha and high inherent viscosity pulp production apparatus, method and system | |
| JP6518287B2 (en) | Method of producing dissolved kraft pulp | |
| CN116590946A (en) | Slurry digestion system | |
| CN112301077A (en) | Method for producing xylooligosaccharide by continuous liquefaction coupling enzyme method of hemicellulose powder | |
| CN115075033A (en) | Method for preparing pulp by prehydrolysis sulfate pulp | |
| CN116695479A (en) | DDS (direct digital synthesizer) cooking process of sulfate bamboo pulp |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20220830 |