In this paper, the results of microscopic observation of rice husk biomass particles by electron scanning microscopy are reported, and the forming mechanism is analyzed, which provides a theoretical basis for improving production process and improving product quality.
The use of biomass compact molding equipment (granule machine, straw briquetting machine feed pellet machine, etc.), to make full use of agricultural and forestry waste such as rice husks, wood chips, straw and other raw material pellet fuel, has good economic and social benefits. Rice husk granules are an emerging product in biomass pellet products. Compared with other types of biomass pellet products, rice husk granules have a wider range of raw materials, lower prices, better molding results, simpler production processes, and good economic, ecological and social benefits.
In this paper, the results of microscopic observation of rice husk biomass particles by electron scanning microscopy are reported, and the forming mechanism is analyzed, which provides a theoretical basis for improving production process and improving product quality.
1. Test materials and methods
1.1 Test materials and instruments
Test material: rice husk biomass pellet, cylindrical, measuring: length 80 mm, diameter 8 mm.
Instrument: Quanta 200 scanning electron microscope (FEI, USA).
1.2 Test methods
Sample preparation: The rice husk was used as a raw material component to produce a molded product of rice husk biomass pellets, and the molding quality was selected for electron microscope observation test.
Electron microscopy: Firstly, the length of the cylindrical specimen with a diameter of 8 mm was cut to 8 mm, and the surface was cleaned with sandpaper. The selected surface is flat, the molding effect is good, and the test piece without serious defects is edited and numbered as the test material. The test piece was then placed with the cross-section facing up on the stage for microscopic observation; after fixing, the surface of the test piece was subjected to gold spray treatment. Finally, the stage was placed in an electron scanning microscope for microscopic observation. After the observation, the selected electron microscope photographs were stored and used for research and analysis.
2. Test results and analysis
2.1 Chemical binding analysis of rice hull granules
From the aspect of chemical combination, we found that the biomass particles using rice husk as raw material are not as tightly packed as the wood particles, and the existence of monolithic rice hulls can be clearly observed. The gap between the two is relatively large, and the sheet-shaped rice hull does not undergo significant bending and deformation. This is because, on the one hand, the outer surface of the rice husk is covered with a layer of inorganic compounds of silicon and silicon (a sheet-like "skin-like" hemispherical protrusion in Fig. 1), which exhibits a network arrangement. Since the chemical properties of silicon and its inorganic compounds are very stable, it is difficult to react with other substances under ordinary conditions, and it has a high hardness. Therefore, in the process of compression molding, when the outer surface of the raw material is in contact with the outer surface, the outer surface and the inner surface, the chemical combination of the polar group-containing cellulose and hemicellulose cannot form hydrogen bonds. Combine. On the other hand, since rice is a herbaceous plant, its cellulose, hemicellulose and lignin are lower in content than wood, especially lignin content is less than 50% of wood, and lignin is a natural bond. When the temperature is 70-110 ° C, the lignin can start to soften and have a certain viscosity. It melts at 200 to 300 ° C and has a high viscosity.
2.2 Physical Binding Analysis of Rice Hull Particles
Analyze from the aspect of physical integration. Microscopically, since the outer surface of the raw rice shell is covered with a layer of siliceous material, this layer of siliceous material has a high hardness, a special arrangement and a three-dimensional structure. Therefore, in the compression molding process, when two rice shells are in contact, it is difficult to closely contact the intermolecular forces, and since silicon and its inorganic compounds are stable substances without polarity, the rice shell is also asked. Does not have electrostatic adsorption. Therefore, the degree of bonding between rice husks is not as tight as sawdust. Macroscopically, the rice hull used in this study has not been pulverized after threshing, and it still maintains the original shape of the rice husk. Its diameter is large, generally between 4 and 7 mm, and it is flaky; it is difficult Forms a tightly packed bond between the wood materials. As can be seen from Fig. 2, between the rice shell raw materials in the rice husk biomass pellets, the sheets and the sheets are layered together.
From Figure 3, significant delamination between the rice shell materials can be observed. This indicates that in the compression molding process of rice shell raw materials, the main raw materials are “bridge†and “bridgeâ€, which is called Solid bridge in English. It is formed by stacking raw materials with a large volume or a certain length and laminating them.
Rice husk granule machine rice husk granule machine
The rice shell material used in this study was in the form of flakes, so we call this combination "sheet" or "lamination". Due to the existence of a harder siliceous layer, the plasticity of the rice shell is extremely poor, and it is difficult to deform during the compression process to achieve close contact between the raw materials, and there is a large gap between the raw materials, so In the combined mode (see Figure 4), the friction between the raw materials is limited; in terms of mechanical resistance, only the shearing and bending resistance perpendicular to the rice shell direction is better, and the mechanical resistance parallel to the rice shell is relatively poor. Compared with woody biomass particles, rice shell particles are prone to faults and the pellets are easily broken. In addition, the rice husk is a hard short fiber biomass material, which has a shorter fiber length than wood; in the compression molding process, there is no fiber-wound combination of wood raw materials.
Rice husk granule machine
3. Conclusion
In this experiment, the rice husk biomass particles were observed and compared by electron microscopy, and the mechanism of the formation and the difference with the wood particles were analyzed. In general, the forming mechanism of rice husk granule products includes chemical bonding and physical bonding. First of all, due to the existence of the siliceous layer, the chemical bonding ability of the rice husk raw material is lower than that of the wood raw material. Secondly, the physical combination between the rice husk raw materials is mainly in the form of “sheet-takingâ€, and the combined effect is better than the wooden material. Slightly worse. In general, the use of rice husk as a raw material for the production of material particles is feasible, the product has a good molding effect, has broad market prospects, and has good economic, ecological and social benefits.
Sanmenxia Futong New Energy sells biomass pellet fuel forming machinery and equipment such as pellet machine, straw pellet machine and rice husk pellet machine.
Information from: Microscopic observation of the formation mechanism of rice husk biomass pellets http://
Http://news.chinawj.com.cn Submission:
PE Rope has high strength, low density, good insulation, stable chemical properties, good chemical resistance and corrosion resistance, and is mainly used in industrial, commercial, construction, marine and fishery applications. Residential use.Polypropylene PP Rope has high strength, low elongation, abrasion resistance, corrosion resistance, economy and sturdiness, and is widely used in most rope requirements.
Pe Rope,Polyethylene Rope,Polypropylene Rope,Pe Plastic Rope
Baoying Yiliyuan Rope And Net Co.,Ltd , http://www.ylyropes.com