CN117431280A - Method for continuously saccharifying lignocellulose as substrate with high solid content - Google Patents

Method for continuously saccharifying lignocellulose as substrate with high solid content Download PDF

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CN117431280A
CN117431280A CN202210836843.XA CN202210836843A CN117431280A CN 117431280 A CN117431280 A CN 117431280A CN 202210836843 A CN202210836843 A CN 202210836843A CN 117431280 A CN117431280 A CN 117431280A
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saccharification
liquid
concentration
cellulase
steady state
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王雅
张斌
鲍杰
徐敏
刘修才
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Cathay R&D Center Co Ltd
CIBT America Inc
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CIBT America Inc
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    • C12P7/00—Preparation of oxygen-containing organic compounds
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Abstract

The invention discloses a high-solid-content continuous saccharification method using lignocellulose as a substrate, which comprises the following steps: (1) Mixing the pretreated lignocellulose raw material with cellulase and water, and performing saccharification reaction to obtain an initial saccharification liquid with the concentration of fermentable sugar of 70-130 g/L; (2) Supplementing the materials in the step (1), taking out part of saccharification liquid at the same time, repeating the process, and reaching a saccharification steady state when the concentration of fermentable sugar and/or apparent viscosity of the saccharification liquid in the system do not change obviously, so as to obtain saccharification slurry in the steady state; wherein the supplementary material comprises pretreated lignocellulose raw material, cellulase and water. The invention can effectively control the apparent viscosity of saccharification slurry, is convenient for transportation and transportation, realizes open pumping and ensures the continuity of production.

Description

Method for continuously saccharifying lignocellulose as substrate with high solid content
Technical Field
The invention belongs to the fields of bioenergy and biorefinery, and particularly relates to a high-solid-content continuous saccharification method using lignocellulose as a substrate.
Background
Continuous operation is a conventional operation of industrial production processes, which has constant operating conditions, fast processing rates, stable product quality, and can achieve higher production efficiency by avoiding emptying, cleaning and switching. The biorefinery process hydrolyzes cellulose and hemicellulose in lignocellulose biomass into fermentable monosaccharides by pretreatment and enzymolysis saccharification, and further ferments and converts the fermentable monosaccharides into high value-added products, the process targets are hydrolysis slurry with high viscosity and high solid particle content, intermittent operation can cause solid precipitation and blockage in a reactor, a container, a pump and a pipeline, the cleaning burden is heavy, the saccharification period is long, and the volume productivity of fermentable sugars in unit time is low, so that the continuously operated biorefinery process is particularly important.
Serialization is a key step in biorefinery, which is a saccharification step that converts solid phase material into a high viscosity liquid phase (or slurry) material. Biorefinery requires fermentation with high concentrations of fermentable monosaccharides as a carbon source, which means that the enzymatic hydrolysis process must be carried out at a higher solids lignocellulosic feedstock content. When the enzymatic saccharification process is conducted under high solids lignocellulosic feedstock conditions, the high viscous nature and high solids content (lignin, etc.) of the hydrolyzed pulp makes conventional press, centrifugal or membrane separation type solid-liquid separation, pump transport difficult to operate, and the hydrolyzed pulp contains high concentrations of cellooligosaccharides that are not directly fermentable monosaccharides. The power consumption of the high solid phase hydrolysis system is determined by the rheological property of materials, and the rheological property is critical to the design of the saccharification reactor. The continuous saccharification process with high solid content realizes open pumping by adjusting the technological parameters and controlling the viscosity of the hydrolysate within the viscosity range for realizing conventional pumping in a short time.
Patent CN105671088B discloses a continuous saccharification and co-fermentation method of lignocellulose modified by a surfactant, which avoids a detoxification step, but does not realize continuous saccharification in a true sense, and the concentration of fermentable sugar obtained by saccharification with low solid content is low, and the concentration of a fermentation product is also inevitably greatly reduced, so that the energy consumption of a separation process is huge and a large amount of wastewater is generated, and meanwhile, a solid-liquid separation process can cause a large amount of fermentable monosaccharide to be lost, so that the method has no characteristics of industrial technology. Patent CN112522347A discloses a method for improving the enzymolysis saccharification efficiency of cellulose in a high-solid enzymolysis system, which reduces the viscosity of the high-solid enzymolysis system and increases the fluidity. However, the residence time of the material in the enzymolysis reactor is too long, resulting in too long a biorefinery cycle. In summary, there are a number of disadvantages to any of the prior art continuous saccharification processes of lignocellulose.
Disclosure of Invention
In order to solve the technical problems, the invention provides a method for continuously saccharifying lignocellulose with high solid content, which can continuously produce fermentable sugar (such as glucose and xylose) without loss, maintain the viscosity of a high-solid continuous saccharifying system, simplify the production process, improve the process efficiency, reduce the risk of bacteria contamination and save the energy consumption, and the obtained saccharified slurry is directly pumped to the subsequent high-solid-content biological processing process, thereby having great industrial application potential.
The invention is realized by the following technical scheme:
a method for continuous saccharification of high solids content with lignocellulose as a substrate, the method comprising the steps of:
(1) Mixing the pretreated lignocellulose raw material with cellulase and water, and performing saccharification reaction to obtain an initial saccharification liquid with the concentration of fermentable sugar of 70-130 g/L;
(2) Supplementing the materials in the step (1), taking out part of saccharification liquid at the same time, repeating the process, and reaching a saccharification steady state when the concentration of fermentable sugar and/or apparent viscosity of the saccharification liquid in the system do not change obviously, so as to obtain saccharification slurry in the steady state; wherein the supplementary material comprises pretreated lignocellulose raw material, cellulase and water.
According to the invention, the method further comprises step (3): the saccharified slurry in the steady state in step (2) is used in a subsequent high solids bioprocess. For example, conventional pumping equipment may be used for open transportation, pumped for subsequent high solids bioprocessing.
According to the invention, in step (1), the lignocellulose raw material is derived from agricultural waste, for example one or more selected from corn stover, wheat straw, cotton stalk, sesame stalk, canola stalk, sweet sorghum stalk, corn cob, rice hull, chaff, bagasse, straw, wood chips, hardwood, cork.
According to the present invention, in step (1), the preprocessing may include: at least one of dilute acid pretreatment, steam explosion pretreatment, ammonia fiber explosion pretreatment, alkali pretreatment and ionic liquid pretreatment. Preferably, the pretreatment mode is dry dilute acid pretreatment. Illustratively, the dilute acid is sulfuric acid, and also illustratively, the lignocellulosic feedstock is treated with dilute acid. In the present invention, the treatment of the lignocellulosic feedstock with dilute acid is carried out using techniques conventional in the art.
According to the invention, in step (1), the water content of the pretreated lignocellulosic feedstock is 40 to 60 wt.%, preferably 48 to 51 wt.%.
According to the invention, in step (1), the inhibitor is included per gram of lignocellulosic feedstock after the intervention: 5-10 mg of furfural, 2-10 mg of hydroxymethyl furfural and 10-20 mg of acetic acid.
According to the invention, in the step (1), the lignocellulose raw material may be subjected to crushing and dust removing treatment before being subjected to pretreatment.
According to the invention, in step (1), the pretreated lignocellulosic feedstock is a solid material that is not detoxified.
According to the invention, in step (1), the solid content of the reaction system is 20 to 30wt%. The solid content of the reaction system refers to the percentage of the total mass of solid raw materials of the pretreated lignocellulose raw material without water to the total mass of the saccharification system in the step (1) (comprising pretreated lignocellulose raw material, cellulase and water).
According to the invention, in the step (1), the mass-volume ratio of the pretreated lignocellulose raw material, the cellulase and the water is (15-60) g, 1mL (10-60) g, preferably (30-60) g, 1mL (15-35) g.
According to the invention, in the step (1), the addition amount of the cellulase is 10-30 FPU/g straw, preferably 12-20 FPU/g straw. The pH of the saccharification reaction system in the step (1) is 4.5-5.5, preferably 4.6-5.0.
According to the invention, in the step (1), an alkaline compound may be added to control the pH value of the saccharification system; the basic compound is selected from Ca (OH) 2 、NaOH、KOH、CaCO 3 One or more of the following. Preferably, the basic compound is Ca (OH) 2 . The concentration of the basic compound is not particularly limited so as to control the pH of the saccharification system within the above-described range.
According to the invention, in step (1), the saccharification reaction is carried out at a temperature of 42-55 ℃, preferably at a temperature of 48-52 ℃.
According to the invention, in step (1), the saccharification reaction is carried out for a period of time ranging from 4 hours to 24 hours, preferably from 5 to 8 hours.
According to the invention, in step (1), the cellulase is an enzyme protein or a mixture of enzyme proteins which are capable of hydrolysing lignocellulose in the art, and commercially available cellulases, such as Norwesternase or Zealand enzymes, may be used.
According to the invention, in step (1), the concentration of fermentable sugars in the initial saccharification liquid is preferably between 100 and 120g/L; the fermentable sugars include glucose and xylose.
According to the present invention, in the step (1), the apparent viscosity of the initial saccharification liquid is 0.4 to 1.5 Pa.s, and more preferably 0.5 to 1 Pa.s.
In the step (1) of the present invention, the rotational speed of the reaction system is not particularly limited, so that the materials are uniformly mixed. Preferably, the rotational speed is 100-300rpm, and is illustratively 150rpm.
According to the invention, in the step (2), part of saccharification liquid and supplementary material are taken out as a circulation.
According to the invention, in the step (2), the material is supplemented to the step (1) repeatedly, and the interval time of the process of taking out part of the saccharification liquid is 5-8 hours until the saccharification steady state is reached, and the continuous saccharification operation is finished. For example, the material is supplemented every 5 to 8 hours, and part of saccharification liquid is taken out until the saccharification steady state is reached, and the continuous saccharification operation is finished. For example, the total continuous saccharification time is 600 hours, the material is supplemented every 6 hours, the material is supplemented every 4 times a day, and the material is supplemented 100 times until the continuous saccharification operation is finished.
According to the invention, in step (2), the quality of the saccharified liquid and the quality of the supplementary material taken out are the same in the same cycle.
According to the invention, in step (2), the total mass of the make-up material is 12-45% (w/w) of the total amount of the reaction raw materials in step (1) (i.e. comprising pretreated lignocellulosic raw materials, cellulase enzymes and water).
According to the present invention, in the step (2), the mass of the saccharified liquid taken out is 12 to 45% (w/w) of the saccharified liquid in the step (1).
According to the invention, in the supplementary material in the step (2), the mass-volume ratio of the pretreated lignin raw material, the cellulase and the water is (15-50) g, 1mL (10-60) g, preferably (20-45) g and 1mL (10-40) g.
According to the invention, in the step (2), the concrete process of taking out part of saccharification liquid and supplementary materials is as follows: firstly, pumping part of saccharification liquid by using a vacuum pump, and then supplementing pretreated lignocellulose solid material, water and cellulase into a saccharification reactor according to the same mass proportion, so as to keep the mass of a saccharification reaction system constant.
According to the present invention, in the step (2), the saccharification steady state means that the saccharification steady state is achieved when the concentration and apparent viscosity of the saccharification slurry do not significantly change.
According to the invention, in step (2), the concentration of fermentable sugars in the saccharification slurry is 80-150 g/L, preferably 110-150 g/L.
According to the invention, in step (2), the apparent viscosity is between 0.1 and 0.7 pa.s, preferably between 0.3 and 0.6 pa.s.
According to the invention, in step (3), the saccharification slurry in step (2) is pumped to high solids content bioprocessing. For example, open pumping may be employed. The saccharification slurry of the invention adopts open pumping, and almost has no risk of bacteria contamination and sugar loss.
According to the invention, in the step (3), the high-solid-content biological processing comprises liquid detoxification, microbial fermentation ethanol production, microbial fermentation oil production, microbial fermentation lactic acid production and other biological refining processes. The invention has the beneficial effects that:
the invention avoids the time and labor-consuming steps of frequent emptying, cleaning, operation switching and the like of the reactor, and the continuous saccharification operation can obviously reduce the process burden and improve the process efficiency;
the pretreated lignocellulose raw material is directly subjected to continuous saccharification without detoxification treatment, and is not interfered by inhibitors such as furfural, hydroxymethylfurfural and acetic acid generated after pretreatment, so that the risk of bacteria contamination is reduced, and the loss of fermentable sugar in saccharification slurry is avoided;
the invention can effectively control the apparent viscosity of saccharification slurry, is convenient for transportation and transportation, realizes open pumping, and ensures the continuity of production;
the invention saves energy consumption, simplifies the production process, reduces the production cost and is suitable for large-scale production and application under the conditions of no wastewater and no solid material loss.
Detailed Description
The technical scheme of the invention will be further described in detail below with reference to specific embodiments. It is to be understood that the following examples are illustrative only and are not to be construed as limiting the scope of the invention. All techniques implemented based on the above description of the invention are intended to be included within the scope of the invention.
Unless otherwise indicated, the starting materials and reagents used in the following examples were either commercially available or may be prepared by known methods.
Example 1
A method for continuous saccharification of high solids content with lignocellulose as a substrate comprising:
(1) Initial conditions for high solids continuous saccharification in a saccharification reactor:
the water content of the wheat straw (solid material) pretreated by dilute acid is 50.23wt%; the solid content of the initial continuous saccharification system is 30wt%, 2000g of pretreated wheat straw and 1250g of water are weighed and added into a saccharification reactor, 48mL of cellulose with the concentration of 12.8FPU/g straw is added into the saccharification reactor, and the pH value is kept at about 4.8 by automatically adding calcium hydroxide solution, and the hydrolysis is carried out for 6 hours under the conditions of 150rpm and 50 ℃ to obtain the initial saccharification liquid.
The concentration of fermentable sugars in the initial saccharification liquid was 118.22g/L (including a glucose concentration of 66.69g/L and a xylose concentration of 51.63 g/L), and the apparent viscosity of the saccharification liquid prior to feeding (i.e., the initial saccharification liquid) was 0.71 Pa.s.
The content of inhibitors in each gram of dry wheat straw after dilute acid pretreatment is as follows: 5.21mg of furfural, 3.19mg of hydroxymethylfurfural and 17.32mg of acetic acid.
(2) Continuously and repeatedly taking and supplementing operation in the saccharification reactor:
pumping 36% (w/w) saccharification liquid, and then supplementing pretreated lignocellulose solid material, cellulase and water to a saccharification reactor according to the ratio of 42.35g to 1mL to 26.47g, keeping the quality of a saccharification reaction system constant, taking out part of the saccharification liquid and the supplement material as a cycle, repeating once every 6 hours, and repeatedly taking and supplementing for 4 times every day until the continuous saccharification operation is finished;
(3) Determination of steady state and results for continuous saccharification process
After the continuous saccharification process reached steady state (i.e., saccharification steady state), the average value of fermentable sugar concentration in the saccharification slurry was 133.40g/L (average glucose concentration was 76.63g/L, average xylose concentration was 56.77 g/L), the total volume productivity of fermentable sugars was 7.988g/L/h, the continuous saccharification rate was 0.027 g/(g straw. H), and the apparent viscosity at saccharification steady state was maintained at 0.56 Pa. S.
Example 2
A method for continuous saccharification of high solids content with lignocellulose as a substrate comprising:
(1) Initial conditions for high solids continuous saccharification in a saccharification reactor:
the water content of the wheat straw (solid material) after dilute acid pretreatment is 50.23wt%. The solid content of the initial continuous saccharification system is 30wt%, 2000g of pretreated wheat straw and 1250g of water are weighed and added into a saccharification reactor, 48mL of cellulose with the concentration of 12.8FPU/g straw is added into the saccharification reactor, and the pH value is kept at about 4.8 by automatically adding calcium hydroxide solution, and the hydrolysis is carried out for 6 hours under the conditions of 150rpm and 50 ℃ to obtain the initial saccharification liquid.
The initial saccharification liquid has a fermentable sugar concentration of 115.33g/L (including a glucose concentration of 65.52g/L and a xylose concentration of 49.80 g/L). The apparent viscosity of the saccharification liquid (i.e., the initial saccharification liquid) prior to feeding was 0.72 Pa.s.
The content of inhibitors in each gram of dry wheat straw after dilute acid pretreatment is as follows: 5.21mg of furfural, 3.19mg of hydroxymethylfurfural and 17.32mg of acetic acid.
(2) Continuously and repeatedly taking and supplementing operation in the saccharification reactor:
pumping 12% (w/w) of saccharification liquid, adding pretreated lignocellulose solid material, cellulase and water into a saccharification reactor according to a ratio of 40g to 1mL to 25g, keeping the volume of a saccharification reaction system constant, taking out part of saccharification liquid and supplementary material as a cycle, repeating the process every 6h, and repeating the process of taking and supplementing for 4 times a day until continuous saccharification operation is finished;
(3) Determination of steady state and results for continuous saccharification process
After the continuous saccharification process reached steady state (i.e., saccharification steady state), the average value of fermentable sugar concentration in the saccharification slurry was 134.62g/L (average glucose concentration was 84.68g/L, average xylose concentration was 49.94 g/L), the total volume productivity of fermentable sugars was 2.692g/L/h, the continuous saccharification rate was 0.009 g/(g straw. H), and the apparent viscosity at saccharification steady state was maintained at 0.36 Pa. S.
Example 3
A method for continuous saccharification of high solids content with lignocellulose as a substrate comprising:
(1) Initial conditions for high solids continuous saccharification in a saccharification reactor:
the water content of the corn stalks (solid material) pretreated by dilute acid is 48.36wt%. The solid content of the initial continuous saccharification system is 30wt%, 2000g of pretreated corn straw and 1400g of water are weighed and added into a saccharification reactor, 48mL of cellulose with the concentration of 12.8FPU/g straw is added into the saccharification reactor, the pH value is kept at about 4.8 by automatically adding calcium hydroxide solution, and hydrolysis is carried out for 6 hours at 150rpm and 50 ℃ to obtain the initial saccharification liquid.
The concentration of fermentable sugar in the initial saccharification liquid was 112.40g/L (glucose concentration 62.68g/L, xylose concentration 49.71 g/L).
The apparent viscosity of the saccharification liquid (i.e., the initial saccharification liquid) prior to feeding was 0.61 Pa.s.
The content of inhibitors in each gram of dry corn straw after dilute acid pretreatment is as follows: 5.13mg of furfural, 3.38mg of hydroxymethylfurfural and 16.65mg of acetic acid.
(2) Continuously and repeatedly taking and supplementing operation in the saccharification reactor:
pumping 36% (w/w) saccharification liquid, adding 45g:1mL:31.56g pretreated lignocellulose solid material, cellulase and water into a saccharification reactor, keeping the volume of a saccharification reaction system constant, taking out part of saccharification liquid and supplementary material as a cycle, repeating once every 6h, and repeating the adding for 4 times a day until continuous saccharification operation is finished;
(3) Determination of steady state and results for continuous saccharification process
After the continuous saccharification process reached steady state (i.e., saccharification steady state), the average fermentable sugar concentration in the saccharification slurry was 121.48g/L (average glucose concentration was 70.21g/L, average xylose concentration was 51.28 g/L), the total fermentable sugar volume productivity was 7.289g/L/h, the continuous saccharification rate was 0.024 g/(g straw. H), and the apparent viscosity at saccharification steady state was maintained at 0.49 Pa. S.
Example 4
A method for continuous saccharification of high solids content with lignocellulose as a substrate comprising:
(1) Initial conditions for high solids continuous saccharification in a saccharification reactor:
the water content of the wheat straw (solid material) after dilute acid pretreatment is 50.23wt%. The solid content of the initial continuous saccharification system is 20wt%, 1200g of pretreated wheat straw and 1700g of water are weighed and added into a saccharification reactor, 28mL of cellulose with the concentration of 12.8FPU/g straw is added into the saccharification reactor, and the pH value is kept at about 4.8 by automatically adding calcium hydroxide solution, and the hydrolysis is carried out for 6 hours under the conditions of 150rpm and 50 ℃ to obtain the initial saccharification liquid.
The concentration of fermentable sugar in the initial saccharification liquid was 78.53g/L (glucose concentration was 47.22g/L and xylose concentration was 31.31 g/L).
The apparent viscosity of the saccharification liquid (i.e., the initial saccharification liquid) prior to feeding was 0.20 Pa.s.
The content of inhibitors in each gram of dry wheat straw after dilute acid pretreatment is as follows: 5.21mg of furfural, 3.19mg of hydroxymethylfurfural and 17.32mg of acetic acid.
(2) Continuously and repeatedly taking and supplementing operation in the saccharification reactor:
pumping 36% (w/w) saccharification liquid, adding pretreated lignocellulose solid material, cellulase and water into a saccharification reactor according to a proportion (43.2 g:1mL:60 g), keeping the volume of a saccharification reaction system constant, taking out part of the saccharification liquid and the supplement material as a cycle, repeating the process once every 6 hours, and repeating the process for 4 times a day until continuous saccharification operation is finished;
(3) Determination of steady state and results for continuous saccharification process
After the continuous saccharification process reached steady state (i.e., saccharification steady state), the average value of fermentable sugar concentration in the saccharification slurry was 94.52g/L (average glucose concentration was 61.47g/L, average xylose concentration was 33.05 g/L), the total volume productivity of fermentable sugars was 1.890g/L/h, the continuous saccharification rate was 0.019 g/(g straw. H), and the apparent viscosity at saccharification steady state was maintained at 0.11 Pa. S.
As can be seen from examples 1-4, the continuous saccharification process of the present invention can achieve high solids saccharification process continuity. In the whole continuous saccharification process, the method is not interfered by the existence of inhibitors, reduces the risk of bacteria contamination, and avoids the loss of fermentable sugar and the inhibition effect on the activity of the cellulose; the invention can effectively control the apparent viscosity of saccharification slurry, realize open pumping, ensure the continuity of production and is convenient for transportation. The invention adopts solid lignocellulose raw material, saves energy consumption under the conditions of no waste water and no solid material loss, simplifies the production process, reduces the production cost, provides important technical support for the continuous saccharification process of lignocellulose raw material and the reactor design, and has great industrial application potential.
The embodiments of the present invention have been described above by way of example. However, the scope of the present invention is not limited to the above embodiments. Any modifications, equivalent substitutions, improvements, etc. made by those skilled in the art, which fall within the spirit and principles of the present invention, are intended to be included within the scope of the present invention.

Claims (10)

1. A process for continuous saccharification of high solids content of lignocellulose as a substrate, comprising the steps of:
(1) Mixing the pretreated lignocellulose raw material with cellulase and water, and performing saccharification reaction to obtain an initial saccharification liquid with the concentration of fermentable sugar of 70-130 g/L;
(2) Supplementing the materials in the step (1), taking out part of saccharification liquid at the same time, repeating the process, and reaching a saccharification steady state when the concentration of fermentable sugar and/or apparent viscosity of the saccharification liquid in the system do not change obviously, so as to obtain saccharification slurry in the steady state;
wherein the supplementary material comprises pretreated lignocellulose raw material, cellulase and water.
2. The method according to claim 1, further comprising step (3): the saccharified slurry in the steady state in step (2) is used in a subsequent high solids bioprocess.
3. The method according to claim 1 or 2, wherein in step (1), the lignocellulosic feedstock is derived from agricultural waste selected from one or more of corn stover, wheat straw, cotton stalk, sesame stalk, canola stalk, sweet sorghum stalk, corn cob, rice hulls, chaff, bagasse, straw, wood chips, hardwood, cork; and/or the number of the groups of groups,
the pH of the saccharification reaction system in the step (1) is 4.5-5.5.
4. A method according to any one of claims 1-3, wherein in step (1) the inhibitor is included per gram of the lignocellulosic feedstock after the intervention: 5 to 10mg of furfural, 2 to 10mg of hydroxymethyl furfural and 10 to 20mg of acetic acid,
preferably, in the step (1), the mass volume ratio of the pretreated lignocellulose raw material to the cellulase to the water is (15-60) g to 1mL (10-60) g,
preferably, in the step (1), the addition amount of the cellulase is 10-30 FPU/g straw,
preferably, in the step (1), the saccharification reaction time is 4-24 hours.
5. The method according to any one of claims 1 to 4, wherein in step (1), the concentration of fermentable sugars in the initial saccharification liquid is 100-120 g/L; the fermentable sugars include glucose and xylose,
preferably, in the step (1), the apparent viscosity of the initial saccharification liquid is 0.4 to 1.5 Pa.s.
6. The method according to any one of claims 1 to 5, wherein in the step (2), the replenishment of the material in the step (1) is repeated while taking out a part of the saccharified liquid is continued for an interval of 5 to 8 hours until the saccharified steady state is reached, and the continuous saccharifying operation is ended.
7. The process according to any one of claims 1 to 6, wherein, preferably, in step (2), the saccharified liquid and the make-up material are taken out in the same cycle in the same mass,
preferably, in the step (2), the total mass of the supplementary materials is 12-45% (w/w) of the total amount of the reaction raw materials in the step (1),
preferably, in the step (2), the mass of the saccharified liquid taken out is 12 to 45% (w/w) of the saccharified liquid in the step (1).
8. The method according to any one of claims 1 to 7, wherein in the supplementing material, the mass-volume ratio of the pretreated lignin raw material, the cellulase and the water is (15-50) g to 1mL (10-60) g.
9. The method according to any one of claims 1 to 8, wherein in step (2) the concentration of fermentable sugars in the saccharification slurry is 80-150 g/L.
10. The method according to any one of claims 1 to 9, wherein in step (2), the apparent viscosity is 0.1 to 0.7 Pa-s.
CN202210836843.XA 2022-07-15 2022-07-15 Method for continuously saccharifying lignocellulose as substrate with high solid content Pending CN117431280A (en)

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