Straw anaerobic fermentation method
By crushing air-dried straw and treating hydrogen peroxide, combined with anaerobic fermentation technology, the problem of low gas production rate of straw materials is solved, and the application efficiency of straw biogas engineering is significantly improved.
Patent Information
- Application Number
- CN202411930487.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-26
- Publication Date
- 2025-03-18
AI Technical Summary
In the prior art, the gas production rate of straw materials is relatively low, which limits the application of straw biogas engineering.
The pH value is adjusted by crushing the air-dried straw into particles and mixing it with the hydrogen peroxide solution, and then adding an anaerobic fermentation inoculum.
Hydrogen peroxide pretreatment destroys the lignocellulosic structure of the straw, improves the contactability of the straw with water and anaerobic microorganisms, and thus improves the gas production rate of straw materials.
Smart Images
Figure CN119639829A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of anaerobic fermentation methods, in particular to a method for anaerobic fermentation of straw. Background Art
[0002] Recycling straw to produce biogas saves resources and reduces environmental pollution. However, because straw contains a complex lignocellulose structure, it is difficult for microorganisms to quickly degrade it, resulting in a low gas production rate for the straw material, which limits the application of straw biogas projects. Summary of the invention
[0003] The main purpose of the present invention is to provide a method for anaerobic fermentation of straw to solve the problem in the prior art that the gas production rate of straw material is low, which limits the application of straw biogas projects.
[0004] In order to achieve the above object, the present invention provides a method for anaerobic fermentation of straw, comprising the following steps: S1, crushing the air-dried straw into straw particles; S2, mixing the straw particles and the hydrogen peroxide solution in a mass ratio of 1:5 to 1:10 to form a mixture; stirring the mixture evenly and leaving it to stand at room temperature for a period of time; S3, adjusting the pH of the mixture to 7.0-8.0 using sodium hydroxide; S4. Passing anaerobic fermentation inoculum into the mixture to carry out anaerobic fermentation.
[0005] Furthermore, in step S2, the concentration of hydrogen peroxide in the hydrogen peroxide solution is 0.6%-1.0%.
[0006] Furthermore, in step S2, the concentration of hydrogen peroxide in the hydrogen peroxide solution is 0.8%.
[0007] Furthermore, in step S2, the mixture is stirred evenly and then allowed to stand at room temperature for 24 hours.
[0008] Furthermore, in step S1, the particle size of the straw particles is 0.1-1 mm.
[0009] Furthermore, in step S4, the anaerobic fermentation inoculum is introduced into the mixture at a volume ratio of 1:1 to the mixture to perform anaerobic fermentation.
[0010] The beneficial effect of the present invention is that in the straw biogas project, the pretreatment of hydrogen peroxide destroys the lignocellulose structure of the air-dried corn straw, thereby promoting the contactability of the air-dried straw with water and anaerobic microorganisms, thereby improving the gas production rate of the straw material. BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The drawings in the specification, which constitute a part of this application, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.
[0012] Figure 1 The diagrams are the structures of the straws treated with hydrogen peroxide under a microscope in different embodiments and comparative examples; Figure 2 It is a comparison chart of the gas production rate of straw materials in different embodiments and comparative examples. DETAILED DESCRIPTION
[0013] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.
[0014] Example 1 Example 1 is code-named G1, and provides a method for anaerobic fermentation of straw, comprising the following steps: S1. crushing air-dried corn stalks into stalk particles with a particle size of 0.1-1 mm; S2. Weigh 3.8 g of the crushed straw particles and 38 mL of a 0.2% hydrogen peroxide solution in an anaerobic bottle to form a mixture. Stir the mixture evenly and let it stand at 25° C. for 24 h. S3, adjusting the pH of the mixture to 7.2 using sodium hydroxide; S4. Add an anaerobic fermentation inoculum of the same volume as the mixture to the mixture, make up the volume of the fermentation liquid to 200 mL with distilled water, and place it in a constant temperature shaker at 37° C. and 120 rpm for anaerobic fermentation.
[0015] After 42 days of anaerobic fermentation, the gas production rate of the straw material was calculated to be 210.26 mL / gVS.
[0016] Example 2 Example 1 is code-named G2, and provides a method for anaerobic fermentation of straw, comprising the following steps: S1. crushing air-dried corn stalks into stalk particles with a particle size of 0.1-1 mm; S2. Weigh 3.8 g of the crushed straw particles and 38 mL of a 0.4% hydrogen peroxide solution in an anaerobic bottle to form a mixture. Stir the mixture evenly and let it stand at 25° C. for 24 h. S3, adjusting the pH of the mixture to 7.2 using sodium hydroxide; S4. Add an anaerobic fermentation inoculum of the same volume as the mixture to the mixture, make up the volume of the fermentation liquid to 200 mL with distilled water, and place it in a constant temperature shaker at 37° C. and 120 rpm for anaerobic fermentation.
[0017] After 42 days of anaerobic fermentation, the gas production rate of the straw material was calculated to be 226.96 mL / gVS.
[0018] Example 3 Example 1 is coded as G3, and provides a method for anaerobic fermentation of straw, comprising the following steps: S1. crushing air-dried corn stalks into stalk particles with a particle size of 0.1-1 mm; S2. Weigh 3.8 g of crushed straw particles and 38 mL of 0.6% hydrogen peroxide solution in an anaerobic bottle to form a mixture. Stir the mixture evenly and let it stand at 25° C. for 24 h. S3, adjusting the pH of the mixture to 7.2 using sodium hydroxide; S4. Add an anaerobic fermentation inoculum of the same volume as the mixture to the mixture, make up the volume of the fermentation liquid to 200 mL with distilled water, and place it in a constant temperature shaker at 37° C. and 120 rpm for anaerobic fermentation.
[0019] After 42 days of anaerobic fermentation, the gas production rate of the straw material was calculated to be 230.67 mL / gVS.
[0020] Example 4 Example 1 is code-named G4, and provides a method for anaerobic fermentation of straw, comprising the following steps: S1. crushing air-dried corn stalks into stalk particles with a particle size of 0.1-1 mm; S2. Weigh 3.8 g of crushed straw particles and 38 mL of 0.8% hydrogen peroxide solution in an anaerobic bottle to form a mixture. Stir the mixture evenly and let it stand at 25° C. for 24 h. S3, adjusting the pH of the mixture to 7.2 using sodium hydroxide; S4. Add an anaerobic fermentation inoculum of the same volume as the mixture to the mixture, make up the volume of the fermentation liquid to 200 mL with distilled water, and place it in a constant temperature shaker at 37° C. and 120 rpm for anaerobic fermentation.
[0021] After 42 days of anaerobic fermentation, the gas production rate of the straw material was calculated to be 278.7 mL / gVS. Example 5 Example 1 is code-named G5, and provides a method for anaerobic fermentation of straw, comprising the following steps: S1. crushing air-dried corn stalks into stalk particles with a particle size of 0.1-1 mm; S2, weighing 3.8 g of the crushed straw particles and 38 mL of a 1.0% hydrogen peroxide solution in an anaerobic bottle to form a mixture, stirring the mixture evenly and letting it stand at 25° C. for 24 h; S3, adjusting the pH of the mixture to 7.2 using sodium hydroxide; S4. Add an anaerobic fermentation inoculum of the same volume as the mixture to the mixture, make up the volume of the fermentation liquid to 200 mL with distilled water, and place it in a constant temperature shaker at 37° C. and 120 rpm for anaerobic fermentation.
[0022] After 42 days of anaerobic fermentation, the gas production rate of the straw material was calculated to be 228.09 mL / gVS.
[0023] Comparative Example The comparative example is coded as NP, and provides a method for anaerobic fermentation of straw, comprising the following steps: S1. crushing air-dried corn stalks into stalk particles with a particle size of 0.1-1 mm; S2, weigh 3.8 g of the crushed straw particles and mix them with 38 mL of clean water in an anaerobic bottle to form a mixture, stir the mixture evenly and let it stand at 25° C. for 24 h; S3, adjusting the pH of the mixture to 7.2 using sodium hydroxide; S4. Add an anaerobic fermentation inoculum of the same volume as the mixture to the mixture, make up the volume of the fermentation liquid to 200 mL with distilled water, and place it in a constant temperature shaker at 37° C. and 120 rpm for anaerobic fermentation.
[0024] After 42 days of anaerobic fermentation, the gas production rate of the straw material was calculated to be 187.05 mL / gVS.
[0025] like Figure 1 As shown, from the analysis of the structural diagrams of the straws treated with hydrogen peroxide under a microscope in different embodiments and comparative examples, it can be seen that the hydrogen peroxide pretreatment produces more holes on the surface of the straws, and the hydrogen peroxide treatment obviously destroys the structure of the straws. Moreover, as the concentration of hydrogen peroxide increases, the degree of damage to the structure of the straws also increases.
[0026] like Figure 2 As shown in the figure, by analyzing the comparison chart of the gas production rate of the straw material in different embodiments and comparative examples, it can be seen that the gas production rate of the straw material in each embodiment is improved compared with that in the comparative example; among them, when the concentration of the hydrogen peroxide solution is 0.8%, the gas production rate of the straw material is the highest, reaching 278.7 mL / g VS, which is 49% higher than that in the comparative example.
[0027] In the straw biogas project, hydrogen peroxide pretreatment destroys the lignocellulose structure of air-dried corn straw, thereby promoting the contact between the air-dried straw and water and anaerobic microorganisms, thereby increasing the gas production rate of the straw material.
[0028] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.
Claims
1. A method for anaerobic fermentation of straw, characterized in that: The following steps are involved: S1, crushing the air-dried straw into straw particles; S2, mixing the straw particles and the hydrogen peroxide solution in a mass ratio of 1:5 to 1:10 to form a mixture; stirring the mixture evenly and leaving it to stand at room temperature for a period of time; S3, adjusting the pH of the mixture to 7.0-8.0 using sodium hydroxide; S4. Passing anaerobic fermentation inoculum into the mixture to carry out anaerobic fermentation.
2. The method for anaerobic fermentation of straw according to claim 1, characterized in that: In step S2, the concentration of hydrogen peroxide in the hydrogen peroxide solution is 0.6%-1.0%.
3. The method for anaerobic fermentation of straw as claimed in claim 2, characterized in that: In step S2, the concentration of hydrogen peroxide in the hydrogen peroxide solution is 0.8%.
4. The method for anaerobic fermentation of straw as claimed in claim 2, characterized in that: In the step S2, the mixture is stirred evenly and then allowed to stand at room temperature for 24 hours.
5. The method for anaerobic fermentation of straw according to claim 1, characterized in that: In the step S1, the particle size of the straw particles is 0.1-1 mm.
6. The method for anaerobic fermentation of straw according to claim 1, characterized in that: In the step S4, the anaerobic fermentation inoculum is introduced into the mixture at a volume ratio of 1:1 to the mixture to perform anaerobic fermentation.