Steam explosion method for improving quality and value of rice straw roughage

Abstract

The invention discloses a steam explosion method for improving quality and value of rice straw roughage, which can destroy fiber structures in straws through steam explosion and hydrolyze cellulose, hemicellulose and hemicellulose macromolecular substances into small molecular substances. According to the method disclosed by the invention, after the pressure is maintained for 150 seconds under the pressure of 1.2 MPa, the content degradation rates of neutral detergent fiber, acid detergent fiber, acid detergent lignin, cellulose and hemicellulose are respectively 31.81%, 37.49%, 43.64%, 36.24% and 52.89%, and the content of crude protein is increased by 11.6%. The relative quality and the relative feeding value of the coarse feed of the rice straws can be obviously improved.

Description

Technical Field

[0001] The invention relates to the technical field of agriculture, and in particular to a steam explosion method for improving the quality and value of rice straw roughage. Background Art

[0002] With the development of agriculture and the growth of population, how to effectively utilize agricultural waste has become an important issue for sustainable agricultural development. As one of the main by-products of agricultural production, rice straw has a huge output, but traditional treatment methods such as burning and discarding not only cause waste of resources, but also cause environmental pollution problems. Therefore, exploring efficient utilization methods of rice straw is of great significance for improving the utilization rate of agricultural resources and promoting the development of agricultural circular economy.

[0003] Steam explosion technology is an emerging biomass pretreatment technology. Through the action of high-temperature and high-pressure steam, it can destroy the plant cell wall structure and change its physical and chemical properties, thereby improving the availability of biomass. In recent years, steam explosion technology has shown great potential in the efficient conversion and utilization of biomass resources such as crop straw and forestry residues.

[0004] Rice straw was treated with steam explosion to explore the effects of different treatment conditions on its nutritional components and feeding value. The application potential of steam explosion technology in the resource utilization of rice straw was evaluated by systematically analyzing the changes in key indicators of roughage quality and value such as dry matter, crude protein, crude ash, soluble carbohydrates, neutral detergent fiber, acid detergent fiber, acid detergent lignin, cellulose and hemicellulose after treatment. The research results will provide scientific basis and technical support for the high-value utilization of rice straw. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention aims to provide a steam explosion method for improving the quality and value of rice straw roughage. The present invention can reprocess rice straw to produce rice straw with improved nutritional value and feeding value, thereby meeting the needs of animal husbandry for excellent feed products.

[0006] In order to achieve the above object, the present invention adopts the following technical solution: A method for steam explosion to improve the quality and value of rice straw roughage, the method comprising the following steps: S1 prepares raw materials, selects appropriate raw materials and performs pretreatment; S2: loading the raw materials, loading the raw materials pretreated in step S1 into a feed bin in the steam explosion equipment; S3: Pressurization and pressure maintenance: high-temperature steam is introduced into the equipment to make the raw materials swell under the high pressure in the steam explosion chamber and maintain the pressure for a period of time; S4 decompression explosion: after maintaining the pressure for a period of time in step S3, the equipment valve is quickly opened to instantly reduce the pressure to normal pressure. The water inside the raw material is quickly vaporized, and the volume expands, causing the raw material to explode. The exploded raw material is collected at the discharge device for subsequent processing or treatment.

[0007] It should be noted that the raw material in step S1 is wood, rice straw or food raw material, and the pretreatment includes cutting and drying.

[0008] It should be noted that, in step S3, the pressure of the water vapor is 1.0-1.4 MPa, and the pressure holding time is 30 s-150 s.

[0009] It should be noted that the pressure of the water vapor is 1.2 MPa and the pressure holding time is 150 s.

[0010] It should be noted that in step S4, after the pressure application and pressure maintenance are completed, the rice straw explodes out from the spray port of the discharging device during the instantaneous pressure release, and the exploded rice straw is collected by a collecting device.

[0011] The beneficial effect of the present invention is that the present invention greatly improves the relative quality and relative feeding value of rice straw roughage, and the steam explosion technology has potential application value in improving the nutrition of rice straw, and can provide higher quality feed resources for animal husbandry, thereby improving the market economic value of rice straw and meeting the development needs of society. DETAILED DESCRIPTION

[0012] The present invention is further described below. It should be noted that this embodiment is based on the technical solution and provides a detailed implementation method and a specific operation process, but the protection scope of the present invention is not limited to this embodiment.

[0013] The present invention provides a steam explosion method for improving the quality and value of rice straw roughage, and the method comprises the following steps: S1 prepares raw materials, selects appropriate raw materials and performs pretreatment; S2: loading the raw materials, loading the raw materials pretreated in step S1 into a feed bin in the steam explosion equipment; S3: Pressurization and pressure maintenance: high-temperature steam is introduced into the equipment to make the raw materials swell under the high pressure in the steam explosion chamber and maintain the pressure for a period of time; S4 decompression explosion: after maintaining the pressure for a period of time in step S3, the equipment valve is quickly opened to instantly reduce the pressure to normal pressure. The water inside the raw material is quickly vaporized, and the volume expands, causing the raw material to explode. The exploded raw material is collected at the discharge device for subsequent processing or treatment.

[0014] Furthermore, the raw material in step S1 of the present invention is wood, rice straw or food raw material, and the pretreatment includes cutting and drying.

[0015] Furthermore, in step S3 of the present invention, the pressure of the water vapor is 1.0-1.4 MPa, and the pressure holding time is 30s-150s.

[0016] Furthermore, the water vapor pressure of the present invention is 1.2 MPa, and the pressure holding time is 150 s.

[0017] Furthermore, in the step S4 of the present invention, after the pressure is applied and maintained, the rice straw explodes out from the spray port of the discharge device during the instantaneous pressure release, and the exploded rice straw is collected by a collecting device. Example The effectiveness of the present invention is demonstrated by the following examples. In this example, naturally air-dried rice straw from the fields of Chuanwan Town, Liling City is used as raw material for steam explosion.

[0018] Put rice straw into the steam explosion feed bin, check and close the equipment door, and pass high-temperature and high-pressure water vapor. The steam pressure and holding time are adjusted according to the type and requirements of the material. The steam pressure gradient set in the present invention is 1.0, 1.2, and 1.4 MPa at three levels, and the holding time is 30, 60, 90, 120, and 150 s at five levels. 15 treatments are completely randomly set; rice straw that has not been subjected to steam explosion treatment is used as a control (raw material group). Under the action of steam, the components such as cellulose, hemicellulose, and lignin in the material will undergo certain changes.

[0019] After the pressure maintenance set under steam treatment is completed, when the pressure relief valve of the steam explosion equipment is opened, the pressure in the steam boiler is instantly reduced, causing the steam inside the rice straw to expand rapidly, generating a strong impact force, and then causing the rice straw to rupture and decompose, and the rice straw will explode from the spray port of the discharge device during the instantaneous pressure relief process; then the rice straw after the explosion is collected by the collection equipment; the products after the steam explosion of rice straw include solid and liquid parts. The solid part is mainly composed of lignin, cellulose, hemicellulose and other components, and the liquid part is water containing various dissolved substances. The solid products are mainly collected for subsequent processing and utilization.

[0020] The experimental results under different treatments are as follows: Table 1 Effects of steam explosion on the nutritional components of rice straw (dry matter basis / %)

[0021] The effects of steam explosion on the conventional nutritional components of rice straw are shown in Table 1. By analyzing the data in the table, it is found that the CP content of the original group and each treatment group is 5.29%~6.13%, the lowest is 1.4 MPa+30 s group and 1.0 MPa+150s group, the CP content is 5.29%, and the highest is 1.2 MPa+150 s group, the CP content is 6.13%; the Ash content of the original group and each treatment group is 10.65%~16.65%, the lowest is 1.4 MPa+30 s group, the Ash content is 10.65%, and the highest is 1.4 MPa+90 s group, its Ash content was 16.65%; compared with the original group, steam explosion treatment significantly increased the WSC content in the straw (P<0.05), the WSC content of the original group and each treatment group was 3.91%~13.68%DM, the lowest was 3.91%DM in the original group, and the highest was 13.68%DM in the 1.4 MPa+90 s group; compared with the original group, steam explosion treatment significantly reduced the NDF content in the straw (P<0.05), the NDF content of the original group and each treatment group ranged from 42.94% to 77.06%, the lowest was 42.94% in the 1.2 MPa+150 s group, and the highest was 77.06% in the original group; the ADF content of the original group and each treatment group was 26.9%~45.86%, the lowest was 1.2 MPa+150 s group, its ADF content was 26.9%, and the highest was 45.86% in 1.4 MPa+30 s group; the ADL content of the original group and each treatment group was 4.01%~13.6%, the lowest was 4.01% in 1.2 MPa+90 s group, and the highest was 13.6% in 1.4 MPa+30 s group; the CEL content of the original group and each treatment group was 26.9%~27.23%, the lowest was 26.9% in 1.2 MPa+150 s group, and the highest was 27.23% in 1.4 MPa+30 s group; compared with the original group, steam explosion treatment significantly reduced the HC content in straw (P<0.05), the HC content of the original group and each treatment group ranged from 15.73% to 34.03%, the lowest was 1.4 The HC content of the MPa+90s group was 15.73%, and the highest was the original sample group with an NDF content of 34.03%.

[0022] Table 2 Effect of steam explosion on the feeding value of rice straw

[0023] As shown in Table 2, the DMI content of the original sample group and each treatment group was 1.55%~2.79%BW, the lowest was 1.55%BW in the original sample group, and the highest was 2.79%BW in the 1.2 MPa+150 s group; the DDM content of the original sample group and each treatment group was 53.16%~67.94%DM, the lowest was 53.16%DM in the 1.4 MPa+30 s group, and the highest was 67.94%DM in the 1.2 MPa+150 s group; the TDN content was 47.90%~62.15%DM, the lowest was 47.90%DM in the 1.4 MPa+30 s group, and the highest was 47.90%DM in the 1.2 MPa+150 s group. The TDN content of the s group was 62.15%DM; the RFQ content was 63.36-141.25, the lowest was the original group with RFQ content of 63.36, and the highest was the 1.2 MPa+150 s group with RFQ content of 141.25; the RFV content was 66.86-147.20, the lowest was the original group with RFV content of 66.86, and the highest was the 1.2 MPa+150 s group with RFV content of 147.20; According to the RFV of the original group and each treatment group, the 1.2 MPa+90 s group, the 1.2 MPa+150 s group and the 1.4 MPa+90 s group were first-level forage, the 1.4 MPa+120 s group and the 1.4 MPa+60 s group were second-level forage, the 1.0 MPa+30 s group, the 1.0 MPa+60 s group, the 1.0 The MPa+120 s group, 1.0 MPa+150 s group, 1.2 MPa+30 s group, 1.2 MPa+60 s group, 1.2 MPa+120 s group and 1.4 MPa+150 s group were third-level forage, the 1.0 MPa+90 s group was fourth-level forage, and the 1.4 MPa+30 s group and the original sample group were fifth-level forage.

[0024] Table 3 Membership function analysis and ranking of nutritional value of rice straw after steam explosion

[0025] It is difficult to evaluate the effect of steam explosion treatment by the size of a single index, so the membership function method is used to comprehensively evaluate the nutritional quality of rice straw. The maximum values ​​of DM, CP, WSC, RFV and RFQ and the minimum values ​​of NDF, ADF, ADL, CEL and HC are selected as reference sequences. The larger the total membership, the higher the ranking and the better the treatment effect.

[0026] In general, the total membership is calculated by the relevant formula. As shown in Table 3, the total membership of each treatment group is ranked as follows: 1.2MPa+150s group>1.2MPa+90s group>1.4MPa+90s group>1.4MPa+120s group>1.4MPa+60s group>1.2MPa+60s group>1.2MPa+30s group>1.2MPa+120s group>1.0MPa+120s group>1.0MPa+150s group>1.0MPa+30s group>1.4MPa+150s group>1.0MPa+60s group>1.0MPa+90s group>1.4MPa+30 s group>original group, that is, when the blasting pressure was 1.2MPa and the holding time was 150s, the degradation rates of neutral detergent fiber, acid detergent fiber, acid detergent lignin, cellulose and hemicellulose were 31.81%, 37.49%, 43.64%, 36.24% and 52.89% respectively, and the crude protein content increased by 11.6%. The blasting effect of rice straw was the best.

[0027] For those skilled in the art, various corresponding changes and modifications can be made according to the above technical solutions and concepts, and all of these changes and modifications should be included in the protection scope of the claims of the present invention.

Claims

1. A method for steam explosion to improve the quality and value of rice straw roughage, characterized in that: The method comprises the following steps: S1 prepares raw materials, selects appropriate raw materials and performs pretreatment; S2: loading the raw materials, loading the raw materials pretreated in step S1 into a feed bin in the steam explosion equipment; S3: Pressurization and pressure maintenance: high-temperature steam is introduced into the equipment to make the raw materials swell under the high pressure in the steam explosion chamber and maintain the pressure for a period of time; S4 decompression explosion: after maintaining the pressure for a period of time in step S3, the equipment valve is quickly opened to instantly reduce the pressure to normal pressure. The water inside the raw material is quickly vaporized, and the volume expands, causing the raw material to explode. The exploded raw material is collected at the discharge device for subsequent processing or treatment.

2. The method for steam explosion of improving the quality and value of rice straw roughage according to claim 1, characterized in that: The raw material in step S1 is wood, rice straw or food raw material, and the pretreatment includes cutting and drying.

3. The method for steam explosion of improving the quality and value of rice straw roughage according to claim 1, characterized in that: In step S3, the pressure of the water vapor is 1.0-1.4 MPa, and the pressure holding time is 30 s-150 s.

4. The method for steam explosion of improving the quality and value of rice straw roughage according to claim 3, characterized in that: The water vapor pressure is 1.2 MPa, and the pressure holding time is 150 s.

5. The method for steam explosion of improving the quality and value of rice straw roughage according to claim 1, characterized in that: In the step S4, after the pressure application and pressure maintenance is completed, the rice straw explodes out from the spray port of the discharge device during the instantaneous pressure release, and the exploded rice straw is collected by a collecting device.

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