CN1880415A - Process for preparing fuel ethanol by using straw fiber materials - Google Patents

Abstract

The invention discloses a process for producing fuel ethanol from straw fiber raw materials, which comprises the following steps: (1) raw material selection; (2) crushing; (3) pretreatment; (4) double-enzyme saccharification; (6) sterilization; 7) Expanded cultivation and application of Pachysolentannophilus P-01; (8) Fermentation; (9) Distillation; It is characterized in that: the method of degrading rice straw with liquid crude enzyme solution is used for pretreatment to degrade lignin, Specific steps (1) Strain: Versicolor versicolor (Coridus versicolor), (2) crude laccase production; ① medium generation conditions; ② fermentation: connect 6 versicolor versicolor strain plugs per 100ml, 28-30 ℃, 150rpm shaking culture for 7 days, filter out the mycelium, and get crude laccase; (3) crude peroxidase production, ① medium ② fermentation: connect 6 rings of Phanerochaete chrysosporium spores per 100ml, 37-39 ℃, cultured statically for 9 days, filtered out mycelium, and obtained crude peroxidase; (4) Enzyme solution degraded rice straw conditions, added 1ml each of crude peroxidase and crude laccase to rice straw powder, mixed evenly, and heated at 45°C , pH4.5 to act on the straw for 72h. The method can increase the yield of ethanol and reduce the cost.

Description

Process for producing fuel ethanol from straw fiber raw materials

technical field

The invention relates to a production method of liquid fuel, in particular to a process for producing fuel ethanol by using straw fiber raw materials.

Background technique

In the context of the serious crisis and serious environmental pollution caused by traditional fossil energy such as coal and oil, fuel ethanol has attracted the attention of the government and society for its advantages such as renewable, non-environmental pollution, and technical clearance in motor vehicles. However, traditional fuel ethanol production mainly uses starchy raw materials such as wheat, corn, and dried potatoes, or sugary raw materials such as sugarcane molasses and beet molasses, which require a large amount of crops and high production costs. my country is a large agricultural country with abundant plant fiber resources. The annual output of crop straw alone reaches 700 million tons. The current utilization is mainly for cooking in rural areas, some are returned to the field, and a small amount is used as energy through gasification and solidification. The utilization level is low. , a serious waste of resources, resulting in serious environmental pollution. If straw-like fiber raw materials are used to produce fuel ethanol, both resources and society will have good benefits. In recent years, someone has invented a method for producing ethanol fuel from fibers. The main process is as follows: (1) Select raw materials: crop straw, mainly including wheat straw, corn straw, rice straw, etc., and dry it naturally for later use. (2) Pulverization: the stalks and straws are pulverized by a hammer mill and sieved into 20-40 mesh rice straw powder. (3) Pretreatment of raw materials: mainly lignin degradation treatment. (4) Double-enzyme saccharification: using cellulase and xylanase to saccharify straw under the conditions of 45° C., pH 4.5, 150 rpm, and a liquid-solid ratio of 15 to obtain reducing sugars. (5) Filtration: the saccharification solution of the straw is filtered to remove solid insoluble matter and become a clear saccharification solution. (6) Sterilization: The saccharification solution adjusted by adding nutrients should be sterilized at 121°C for 30 minutes. (7) Fermentation: P-01 was used to ferment the saccharification liquid with an initial sugar concentration of 6% at 30° C. for a period of 84 hours. (8) Distillation: This operation adopts tower or column distillation in industrial production, which is exactly the same as the distillation method in current industrial production. Although the above-mentioned process can produce fuel ethanol by using crop stalks, the production rate of ethanol fuel is affected due to the inadequate pretreatment method of raw materials, so that the cost of producing ethanol is too high.

Contents of the invention

The purpose of the present invention is to provide a process for producing fuel ethanol from straw-like fiber raw materials which can improve the ethanol output rate and reduce the cost after improving the pretreatment method of straw-like fiber raw materials.

The technical solution of the present invention is: a process for producing fuel ethanol from straw fiber raw materials, comprising the following steps

(1) Raw materials: crop stalks, mainly including wheat stalks, corn stalks, rice straw, etc., after natural drying, set aside;

(2) Pulverization: the stalks and straws are pulverized by a hammer mill and sieved into 20-40 mesh rice straw powder;

(3) Pretreatment: The raw material is subjected to lignin degradation treatment in a liquid culture mode by white rot fungi;

(4) Double-enzyme saccharification: use cellulase and xylanase to saccharify straw under the conditions of 45°C, pH 4.5, 150rpm, and a liquid-solid ratio of 15 to obtain reducing sugars;

(5) Filtration: the saccharification solution of the straw is filtered to remove solid insoluble matter and become a clear saccharification solution;

(6) Sterilization: the saccharification solution adjusted by adding nutrients should be sterilized at 121°C for 30 minutes;

(7) Expanded cultivation and application of Pachysolen tannophilus P-01: expand the culture of P-01 with basic medium, then insert the fermentation medium with 10% inoculum size for fermentation;

Basic Medium A (g/100ml): MgSO ₄ ·7H ₂ O 0.05, CaCl ₂ ·H ₂ O 0.01, KH ₂ PO ₄ 0.1, (NH ₄ ) ₂ SO ₄ 0.5, NaCl 0.01, Agar 2.0, pH 5.0 ;

(8) Fermentation: use P-01 to ferment the saccharification liquid with an initial sugar concentration of 6% at 30°C, and the cycle is 84h;

(9) Distillation: This operation adopts tower or column distillation in industrial production, which is exactly the same as the distillation method in current industrial production.

The key point of this technology is in the raw material pretreatment stage, using biological method liquid crude enzyme solution to degrade rice straw, using microorganisms to destroy the integrity of lignocellulose structure and completely decomposing part of lignin into carbon dioxide and water, so that lignocellulose is easier to be processed The saccharification stage is acted on by cellulase.

Specific steps of preprocessing

(1) Strain: Versicolor versicolor (Coridus versicolor), characteristics: donated by the Chinese Academy of Agricultural Sciences Shanghai Edible Fungus, a fungus that can produce lignin-decomposing enzymes under medium conditions, including lignin Peroxidase, manganese-dependent peroxidase and laccase, etc.; (2) Crude laccase production; ① Medium production conditions Glucose 2g/l, ammonium tartrate 12mmol/L, pH4.5 acetic acid-sodium acetate buffer 10mmol /L, KH ₂ PO ₄ 1.47×10 ^-2 mol/L, MgSO ₄ 7H ₂ O 2.03×10 ^-3 mol/L, CaCl ₂ 2H ₂ O 6.8×10 ^-4 mol/L, VB ₁ 2.97× 10 ^-6 mol/L, trace element mixture 7ml/L, Tween 80 1g/L. The material volume ratio is 1:5, sterilized at 121°C for 30 minutes; the composition of the trace element mixture is as follows: aminoacetic acid 7.8×10 ^-3 mol/L, MgSO ₄ ·7H ₂ O 1.2×10 ^-2 mol/L, MnSO ₄ · H ₂ O 2.9×10 ^-3 mol/L, NaCl 1.7×10 ^-2 mol/L, FeSO ₄ ·7H ₂ O 3.59×10 ^-4 mol/L, CoCl ₂ 7.75×10 ^-4 mol/L, CaCl ₂ 2H ₂ O 9.0×10 ^-4 mol/L, ZnSO ₄ 7H _{2 O} 3.48×10 ^-4 mol/L, CuSO ₄ 5H ₂ O 4×10 ^-5 mol/L, KAl(SO ₄ ) ₂ 12H ₂ O 2.1×10 ^-5 mol/L, HBO ₃ 1.6×10 ^-4 mol/L, NaMnO ₄ 4.1×10 ^-5 mol/L; ② Fermentation: Inoculate 6 Versicolor Versicolor strains per 100ml Stopper, 28～30 ℃, 150rpm shaking culture 7d, filter mycelia, get crude laccase; (3) Crude peroxidase production, ① medium glucose 10g/l, ammonium tartrate 2mmol/L, pH 4.5 acetic acid- Sodium acetate buffer 10mmol/L, KH ₂ PO ₄ 2g/L, MgSO ₄ 7H ₂ O 0.5g/L, CaCl ₂ 2H ₂ O 0.1g/L, VB ₁ 1mg/L, reveratrol 3mmol/L , trace element mixture 7ml/L (the formula is the same as above), Tween 80 1g/L; ②Fermentation: add 6 rings of Phanerochaete chrysosporium spores per 100ml, culture at 37-39°C for 9 days, filter out the hyphae , to obtain crude peroxidase; (4) Enzyme solution degrades rice straw conditions, add crude peroxidase and crude laccase 1ml each to rice straw powder, mix well, and act on straw for 72h at 45°C and pH4.5 .

Detailed ways

A process for producing fuel ethanol from straw-like fiber raw materials, comprising the following steps: (1) raw material selection: crop straws, after natural drying, for later use; (2) crushing: straws and straws are pulverized by a hammer mill and sieved into 20-40 (3) pretreatment; (4) dual-enzyme saccharification: use cellulase and xylanase to saccharify straw under the conditions of 45°C, pH 4.5, 150rpm, and a liquid-solid ratio of 15 to obtain Reducing sugar; (5) Filtration: The saccharification solution of straw is filtered to remove solid insoluble matter and then becomes a clear saccharification solution; (6) Sterilization: The saccharification solution adjusted by adding nutrients must be sterilized at 121°C for 30 minutes Treatment; (7) Expanded cultivation and application of Pachysolen tannophilus P-01: expand the culture of P-01 with basic medium, and then insert 10% of the inoculum into the fermentation medium for fermentation; The basic medium is A (g/100ml): MgSO ₄ ·7H ₂ O 0.05, CaCl ₂ ·H ₂ O 0.01, KH ₂ PO ₄ 0.1, (NH ₄ ) ₂ SO ₄ 0.5, NaCl 0.01, agar 2.0, pH5. 0.

(8) Fermentation: Use P-01 to ferment the saccharified liquid with an initial sugar concentration of 6% at 30°C, with a cycle of 84 hours; (9) Distillation: This operation adopts tower or column distillation in industrial production, which is different from the current industrial production The distillation method is exactly the same; its feature is: the pretreatment adopts the method of degrading rice straw with liquid crude enzyme liquid to degrade lignin, and the specific steps (1) strain: Versicolor versicolor (Coridus versicolor), characteristics: developed by China Agricultural Donated by the Shanghai Edible Fungi Institute of the Academy of Sciences, it is a fungus that can produce lignin-decomposing enzymes under medium conditions, including lignin peroxidase, manganese-dependent peroxidase and laccase; (2) Crude Laccase production; ① Medium production conditions glucose 2g/l, ammonium tartrate 12mmol/L, pH4.5 acetic acid-sodium acetate buffer 10mmol/L, KH ₂ PO ₄ 1.47×10 ^-2 mol/L, MgSO ₄ ·7H ₂ O 2.03×10 ^-3 mol/L, CaCl ₂ 2H ₂ O 6.8×10 ^-4 mol/L, VB ₁ 2.97×10 ^-6 mol/L, trace element mixture 7ml/L, Tween 80 1g/ L. The material volume ratio is 1:5, sterilized at 121°C for 30 minutes; the composition of the trace element mixture is as follows: aminoacetic acid 7.8×10 ^-3 mol/L, MgSO ₄ ·7H ₂ O 1.2×10 ^-2 mol/L, MnSO ₄ · H ₂ O 2.9×10 ^-3 mol/L, NaCl 1.7×10 ^-2 mol/L, FeSO ₄ ·7H ₂ O 3.59×10 ^-4 mol/L, CoCl ₂ 7.75×10 ^-4 mol/L, CaCl ₂ 2H ₂ O 9.0×10 ^-4 mol/L, ZnSO ₄ 7H _{2 O} 3.48×10 ^-4 mol/L, CuSO ₄ 5H ₂ O 4×10 ^-5 mol/L, KAl(SO ₄ ) ₂ 12H ₂ O 2.1×10 ^-5 mol/L, HBO ₃ 1.6×10 ^-4 mol/L, NaMnO ₄ 4.1×10 ^-5 mol/L; ② Fermentation: Inoculate 6 Versicolor Versicolor strains per 100ml Stopper, 28～30 ℃, 150rpm shaking culture 7d, filter mycelia, get crude laccase; (3) Crude peroxidase production, ① medium glucose 10g/l, ammonium tartrate 2mmol/L, pH 4.5 acetic acid- Sodium acetate buffer 10mmol/L, KH ₂ PO ₄ 2g/L, MgSO ₄ 7H ₂ O 0.5g/L, CaCl ₂ 2H ₂ O 0.1g/L, VB ₁ 1mg/L, reveratrol 3mmol/L , trace element mixture 7ml/L (the formula is the same as above), Tween 80 1g/L; ②Fermentation: add 6 rings of Phanerochaete chrysosporium spores per 100ml, culture at 37-39°C for 9 days, filter out the hyphae , to obtain crude peroxidase; (4) Enzyme solution degrades rice straw conditions, add crude peroxidase and crude laccase 1ml each to rice straw powder, mix well, and act on straw for 72h at 45°C and pH4.5 .

Comparison between this technology and traditional technology

1. Low cost craft Production cycle (d) Raw material (dry weight) ethanol yield (%) Product cost per ton (yuan) Process without pretreatment 6.25 3.33 3150 Pretreatment process of liquid enzyme solution degradation 9.25 7.31 2540 Traditional starchy raw material process 5 42% 3300

2. Small environmental pollution craft environmental pollution use this technology The pH is between 6-7.5, there is no large amount of acid radical ions and metal ions in the water body, the pollution to the environment is small, and the pollution is easy to control Pretreatment process using acid hydrolysis When the pH is between 2-3, there are a lot of acid radical ions in the water body, the environmental pollution is serious, and the pollution is difficult to control Pretreatment process using alkaline hydrolysis The pH is between 10-11, there are a lot of metal ions in the water, the COD is seriously exceeded, the environmental pollution is serious, and the pollution is difficult to control

3. Mild conditions craft condition equipment requirements use this technology The action pH is between 6-7.5 Low requirements, general carbon steel is enough, low equipment cost Pretreatment process using acid hydrolysis The action pH is between 1.5-2 High requirements, need stainless steel, high equipment cost Pretreatment process using alkaline hydrolysis The action pH is between 11-12 High requirements, need stainless steel, high equipment cost

Claims (2)

1. A process for producing fuel ethanol from straw-like fiber raw materials, comprising the following steps (1) raw material selection: crop straws, after natural drying, for later use; (2) crushing: straws and straws are pulverized by a hammer mill and sieved into 20 ~40 mesh rice straw powder; (3) pretreatment; (4) double enzyme saccharification: use cellulase and xylanase to saccharify straw at 45°C, pH4.5, 150rpm, and liquid-solid ratio of 15 , to obtain reducing sugar; (5) Filtration: the saccharification solution of straw is filtered to remove solid insolubles and then becomes a clear saccharification solution; (6) Sterilization: the saccharification solution adjusted by adding nutrients needs to pass through 121 ° C for 30 minutes Sterilization; (7) Expansion cultivation and application of Pachysolen tannophilus P-01: expand cultivation of P-01 with basal medium, and then insert 10% inoculum into fermentation medium for Fermentation; (8) Fermentation: use P-01 to ferment the saccharification liquid with an initial sugar concentration of 6% at 30°C, and the cycle is 84h; (9) Distillation: This operation adopts tower or column distillation in industrial production, which is different from the current The distillation method in industrial production is exactly the same; it is characterized in that: pretreatment adopts the method of degrading rice straw with liquid crude enzyme solution to carry out lignin degradation treatment, specific steps (1) strain: Versicolor versicolor (Coridus versicolor), characteristic: by Donated by the Shanghai Institute of Edible Fungi, Chinese Academy of Agricultural Sciences, it is a fungus that can produce lignin-decomposing enzymes under medium conditions, including lignin peroxidase, manganese-dependent peroxidase and laccase; (2) ) production of crude laccase; ① medium production conditions glucose 2g/l, ammonium tartrate 12mmol/L, pH4.5 acetic acid-sodium acetate buffer 10mmol/L, KH ₂ PO ₄ 1.47×10 ^-2 mol/L, MgSO ₄ ·7H ₂ O 2.03×10 ^-3 mol/L, CaCl ₂ ·2H ₂ O 6.8×10 ^-4 mol/L, VB ₁ 2.97×10 ^-6 mol/L, trace element mixture 7ml/L, Tween 80 1g/L. The material volume ratio is 1:5, sterilized at 121°C for 30 minutes; the composition of the trace element mixture is as follows: aminoacetic acid 7.8×10 ^-3 mol/L, MgSO ₄ ·7H ₂ O 1.2×10 ^-2 mol/L, MnSO ₄ · H ₂ O 2.9×10 ^-3 mol/L, NaCl 1.7×10 ^-2 mol/L, FeSO ₄ ·7H ₂ O 3.59×10 ^-4 mol/L, CoCl ₂ 7.75×10 ^-4 mol/L, CaCl ₂ 2H ₂ O 9.0×10 ^-4 mol/L, ZnSO ₄ 7H ₂ O 3.48×10 ^-4 mol/L, CuSO ₄ 5H ₂ O 4×10 ^-5 mol/L, KAl(SO ₄ ) ₂ 12H ₂ O 2.1×10 ^-5 mol/L, HBO ₃ 1.6×10 ^-4 mol/L, NaMnO ₄ 4.1×10 ^-5 mol/L; ② Fermentation: Inoculate 6 Versicolor Versicolor strains per 100ml Stopper, 28～30 ℃, 150rpm shaking culture 7d, filter mycelia, get crude laccase; (3) Crude peroxidase production, ① medium glucose 10g/l, ammonium tartrate 2mmol/L, pH 4.5 acetic acid- Sodium acetate buffer 10mmol/L, KH ₂ PO ₄ 2g/L, MgSO ₄ 7H ₂ O 0.5g/L, CaCl ₂ 2H ₂ O 0.1g/L, VB ₁ 1mg/L, reveratrol 3mmol/L , trace element mixture 7ml/L (formula as above), Tween 801g/L; ②Fermentation: connect 6 rings of Phanerochaete chrysosporium spores per 100ml, 37～39°C, static culture for 9d, filter out mycelia, Obtain crude peroxidase; (4) Enzyme solution degrades rice straw conditions, add crude peroxidase and crude laccase 1ml each to rice straw powder, mix well, and act on straw at 45° C. and pH 4.5 for 72 hours. 2. The method for producing fuel ethanol from straw fiber raw materials according to claim 1, characterized in that: the basic medium is A (g/100ml): MgSO ₄ ·7H ₂ O 0.05, CaCl ₂ ·H ₂ O 0.01, KH ₂ PO ₄ 0.1, (NH ₄ ) ₂ SO ₄ 0.5, NaCl 0.01, Agar 2.0, pH 5.0.