High-temperature-resistant stirring magneton for hydrothermal liquefaction of biomass as well as preparation method and application of high-temperature-resistant stirring magneton

Abstract

The invention discloses a high-temperature-resistant stirring magneton for biomass hydrothermal liquefaction as well as a preparation method and application of the high-temperature-resistant stirring magneton, and belongs to the technical field of high-temperature-resistant stirring magnetons. The magneton is composed of a magnet and a sheath. The sheath comprises a main body and a plug; the magnet is arranged in an inner cavity of the main body, and the plug is used for sealing the magnet and the main body; the magnet is one of a samarium cobalt magnet and an aluminum nickel cobalt magnet, and the material of the sheath is one of 0Cr17Ni12Mo2 (316), 0Cr17Ni14Mo2 (316L), a C-276 Hastelloy (UNS N10276), a B-3 Hastelloy (UNS N10675) and a titanium alloy TA2. The magneton has the beneficial effects that the magneton applied to biomass hydrothermal liquefaction (in a high-temperature and high-pressure environment with acid and alkali) is provided, the magneton is provided with limited materials and shape ranges of the magnet and the metal outer sheath, and the magneton can be used in a high-temperature acid and alkali-containing aqueous solution environment at the temperature of 500 DEG C; the application prospect and the economic value are relatively high.

Description

Technical Field

[0001] The invention relates to the technical field of high temperature resistant stirring magnetons, and in particular to a high temperature resistant stirring magneton for biomass hydrothermal liquefaction and a preparation method and application thereof. Background Art

[0002] Biomass refers to organic matter produced by plants or animals, such as wood, crop waste, livestock and poultry manure, etc. As a renewable energy source, biomass has the advantages of extensive resources, easy access, and reduced greenhouse gas emissions, so it has attracted widespread attention and utilization.

[0003] Biomass hydrothermal liquefaction is a technology that converts biomass into liquid products under high temperature and high pressure water phase conditions. The development of this technology helps to solve energy and environmental problems, reduce dependence on fossil fuels, and achieve efficient utilization and recycling of biomass resources.

[0004] Biomass undergoes multiple stages of transformation during the hydrothermal liquefaction process. First, the main components of biomass such as cellulose, hemicellulose and lignin will be hydrolyzed into sugars, organic acids and other soluble low-molecular products. These products further undergo dehydration, deoxygenation and other reactions, and the resulting low-molecular compounds include alcohols, ketones or 5-hydroxymethylfurfural (HMF). In the above process, hydrothermal liquefaction mainly occurs at a water temperature of 200-500°C and a pressure of 5-30MPa in the presence of acid or alkali. There has been no report of a stirring magnet that meets the above high temperature and high pressure and is resistant to acid and alkali corrosion.

[0005] Common permanent magnet materials include neodymium magnets, samarium cobalt magnets, aluminum nickel cobalt magnets, and ferrite magnets. The above magnets may experience flux attenuation at high temperatures. During the welding process, the influence of the welding process on the magnets must be addressed to prevent demagnetization at high temperatures.

[0006] When researchers in universities or enterprises are working on the hydrothermal liquefaction of biomass, when using an intermittent reactor or a continuous reactor, magnets will be used in the solution to mix and stir the solution. At present, there are two types of materials for the outer shells of magnets on the domestic and foreign markets: polytetrafluoroethylene or glass. For magnets with polytetrafluoroethylene outer shells, due to the material properties of polytetrafluoroethylene itself, the use temperature is generally lower than 300°C, and the actual use temperature is generally controlled below 260°C. For magnets with glass outer shells, because glass is a brittle material, it is easy to break when stress impact occurs with the inner bottom wall or inner side wall during use. In addition, the linear expansion coefficients of the outer glass shell and the inner magnet are very different. At high temperatures, the glass will be damaged by the expansion of the magnet.

[0007] In some processes, the magnet is placed in the inner cavity of the glass, leaving a certain gap to offset the destructive force of expansion under high temperature. However, this amount of shaking further makes the brittle glass easy to be damaged. In summary, the operating temperature of glass magnets generally does not exceed 450°C, and they are particularly easy to break (after breaking, the glass slag and magnets will contaminate the solution sample). Therefore, at present, researchers have to use mechanical stirring devices at high temperatures exceeding 300°C, but the introduction of this structure, in addition to increasing costs, also further increases the risk of leakage and failure rate. There are no reports of stirring magnets that can withstand high temperatures of 500°C. Summary of the invention

[0008] The technical problem to be solved by the present invention is how to solve the problem of poor performance of existing stirring magnets.

[0009] The present invention solves the above technical problems through the following technical means:

[0010] The first aspect of the present invention proposes a high-temperature resistant stirring magnet for biomass hydrothermal liquefaction, which consists of a magnet and a sheath; the sheath includes a main body and a plug; the magnet is arranged in the inner cavity of the main body, and the plug is used to seal the magnet and the main body; the magnet is one of a samarium cobalt magnet and an aluminum nickel cobalt magnet, and the material of the sheath is one of 0Cr17Ni12Mo2 (316), 0Cr17Ni14Mo2 (316L), C-276 Hastelloy (UNS N10276), B-3 Hastelloy (UNS N10675), and titanium alloy TA2.

[0011] Preferably, a loose fiber pad layer made of high temperature resistant quartz material is also placed at the bottom of the inner cavity of the main body.

[0012] (The purpose is to release the stress caused by different thermal expansion and contraction coefficients of different materials (magnets, sheaths))

[0013] Preferably, the magnet is a samarium-cobalt magnet, with the element content of Sm 22-28%, Co 44-53%, Fe 15-18%, Zr 2-3.5%, Tb 2-5%, and Cu 5-8%.

[0014] Preferably, the magnetization direction of the samarium cobalt magnet is axial; and the magnetization intensity is not less than 2000 Gs.

[0015] Preferably, the shape of the sheath is one of a cylinder, a square column, a cross, a triangle, and an olive shape.

[0016] Preferably, the length of the magnet is between 10 mm and 150 mm.

[0017] Preferably, the applicable volume range of the magnet is 50ml to 10L.

[0018] The second aspect of the present invention proposes a method for preparing the above-mentioned high-temperature resistant stirring magnet, comprising the following steps: placing the magnet in the inner cavity of the main body, then inserting a plug, and welding and sealing it under a protective gas atmosphere; the welding method is laser welding, the scanning speed is between 200 and 800 mm / s, the scanning width is between 0.5 and 2 mm, the peak power is between 220 and 550 watts, the pulse frequency is between 1000 and 3000 Hz, and the wire feeding speed is between 0.5 and 2 mm / s; and the duration of a single welding process does not exceed 10 seconds. If it exceeds, the welding should be performed again after the temperature of the weldment drops below 100°C.

[0019] Preferably, the protective gas is an inert gas, more preferably argon or helium.

[0020] The third aspect of the present invention proposes the application of the high temperature resistant stirring magnet in the field of biomass hydrothermal liquefaction.

[0021] The beneficial effects of the present invention are:

[0022] 1. The present invention invents a magnet that can be stirred in a high-temperature environment up to 500°C through a certain range of suitable magnets and suitable metal outer sheaths, and through suitable processing technology and parameters, to meet the stirring and mixing of aqueous solutions for biomass hydrothermal liquefaction (high temperature, high pressure, acid and alkali environment).

[0023] 2. After a lot of theoretical research, experiments and test iterations, based on the working conditions of researchers, suitable magnets and metal outer sheaths were customized, and welding process methods were explored. It can be used for biomass hydrothermal liquefaction at water temperatures of 200-500℃ and pressures of 5-30MPa in the presence of acid or alkali.

[0024] 3. Customized suitable magnets and metal outer sheaths, invented magnetic particles that can be used for hydrothermal liquefaction of biomass at water temperatures of 200-500℃ and pressures of 5-30MPa in the presence of acid or alkali. The applicable volume range of magnetic particles is 50ml to 10L.

[0025] 5. Appropriate processing technology and parameters to ensure the performance stability of the magnet. In order to solve the above problems, after a lot of theoretical research, experiments and test iterations, based on the working conditions of scientific researchers, suitable magnets and suitable metal outer sheaths were customized, and welding process methods were explored. And long-term test data was carried out. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic structural diagram of a high temperature resistant stirring magnet according to Example 1 of the present invention;

[0027] Figure 2This is a physical picture of the high temperature resistant stirring magnet of Example 1 of the present invention;

[0028] Figure 3 for Figure 2 Another perspective of the picture;

[0029] Figure 4 Schematic diagram of the structure of the high temperature resistant stirring magnet in Example 2 of the present invention, wherein A is a cross, B is a triangle, and C is an olive.

[0030] In the figure, 1-main body, 2-magnet, 3-cushion, 4-plug, 5-welding seal. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] Unless otherwise specified, the test materials and reagents used in the following examples can be obtained from commercial sources.

[0033] If no specific techniques or conditions are specified in the examples, they can be carried out according to the techniques or conditions described in the literature in the art or according to the product instructions.

[0034] Embodiment 1:

[0035] A high temperature resistant stirring magnet for biomass hydrothermal liquefaction, the magnet is composed of a magnet and a sheath; the sheath includes a main body and a plug; the magnet is arranged in the inner cavity of the main body, and the plug is used to seal the magnet and the main body; the sealing is completed by welding; a loose fiber cushion layer of high temperature resistant quartz material is placed at the bottom of the inner cavity of the main body; the magnet is a samarium cobalt magnet (element content Sm 25%, Co 50%, Fe16%, Zr2%, Tb2%, Cu5%. Magnetization direction: axial; magnetization intensity is 2000Gs), and the material of the sheath is C-276 Hastelloy (UNS N10276). The sheath is cylindrical (inner diameter 16mm, length 60mm),

[0036] The preparation method of the high temperature resistant stirring magnet comprises the following steps:

[0037] The welding process used is: laser welding, the shielding gas is argon, the scanning speed is 500mm / s, the scanning width is 1mm, the peak power is 300 watts, the pulse frequency is 2000Hz, and the wire feeding speed is 1mm / s. The duration of a single welding process does not exceed 10 seconds. If it exceeds, the temperature of the welded part should be reduced to below 100℃ before welding again.

[0038] The magnetron prepared in this example was used to carry out a hydrothermal liquefaction experiment of wheat stems in a 1L reactor under atmosphere. A weakly alkaline catalyst was used to carry out the biomass hydrothermal liquefaction reaction at a reaction temperature of 375°C, a rotation speed of 800 rpm, and a reaction time of 45 min.

[0039] Through analysis, the experimental results show that: it can effectively promote the hydrothermal liquefaction of biomass, and the total conversion rate of wheat stalk liquefaction can reach more than 50%, and the yield of liquid products is about 20%.

[0040] The magnet of this embodiment was subjected to a high temperature resistance test, and the magnetic flux of the magnet before and after the test was tested. The results are shown in the following table:

[0041]

[0042] Embodiment 2:

[0043] The difference between this embodiment and embodiment 1 is that the sheath is cross-shaped, triangular or olive-shaped (schematic diagram as shown in FIG. Figure 4 shown).

[0044] Embodiment 3:

[0045] The difference between this embodiment and embodiment 1 is that the magnet is a samarium-cobalt magnet, and the element contents are Sm 22%, Co 53%, Fe 15%, Zr 3.5%, Tb 2%, and Cu 8%.

[0046] Embodiment 4:

[0047] The difference between this embodiment and embodiment 1 is that the magnet is a samarium-cobalt magnet, and the element contents are Sm 28%, Co 44%, Fe 18%, Zr 2%, Tb 5%, and Cu 5%.

[0048] Embodiment 5:

[0049] The difference between this embodiment and embodiment 1 is that during laser welding, the scanning speed is 200 mm / s, the scanning width is 2 mm, the peak power is 220 watts, the pulse frequency is 1000 Hz, and the wire feeding speed is 2 mm / s.

[0050] Embodiment 6:

[0051] The difference between this embodiment and embodiment 1 is that during laser welding, the scanning speed is 800 mm / s, the scanning width is 0.5 mm, the peak power is 550 watts, the pulse frequency is 3000 Hz, and the wire feeding speed is 0.5 mm / s.

[0052] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high temperature resistant stirring magnet for biomass hydrothermal liquefaction, characterized in that: The magnet is composed of a magnet and a sheath; the sheath includes a main body and a plug; the magnet is arranged in the inner cavity of the main body, and the plug is used to seal the magnet and the main body; the magnet is one of a samarium-cobalt magnet and an aluminum-nickel-cobalt magnet, and the material of the sheath is one of 0Cr17Ni12Mo2 (316), 0Cr17Ni14Mo2 (316L), C-276 Hastelloy (UNS N10276), B-3 Hastelloy (UNS N10675), and titanium alloy TA2.

2. The high temperature resistant stirring magnet for biomass hydrothermal liquefaction according to claim 1, characterized in that: The magnet is a samarium-cobalt magnet, with element contents of Sm 22-28%, Co 44-53%, Fe 15-18%, Zr 2-3.5%, Tb 2-5%, and Cu 5-8%. The magnetization direction of the samarium-cobalt magnet is axial; and the magnetization intensity is not less than 2000Gs.

3. The high temperature resistant stirring magnet for biomass hydrothermal liquefaction according to claim 1, characterized in that: A loose fiber pad layer made of quartz is also placed at the bottom of the inner cavity of the main body.

4. The high temperature resistant stirring magnet for biomass hydrothermal liquefaction according to claim 1, characterized in that: The shape of the sheath is one of a cylinder, a square column, a cross, a triangle, and an olive shape.

5. The high temperature resistant stirring magnet for biomass hydrothermal liquefaction according to claim 1, characterized in that: The length of the magnet is between 10 mm and 150 mm.

6. The high temperature resistant stirring magnet for biomass hydrothermal liquefaction according to claim 1, characterized in that: The applicable volume range of the magnet is 50ml to 10L.

7. The method for preparing a high temperature resistant stirring magnet according to any one of claims 1 to 5, characterized in that: The following steps are involved: The magnet is placed in the inner cavity of the main body, and then the plug is placed in, and welding and sealing are performed under a protective gas atmosphere; the welding method is laser welding, the scanning speed is between 200 and 800 mm / s, the scanning width is between 0.5 and 2 mm, the peak power is between 220 and 550 watts, the pulse frequency is between 1000 and 3000 Hz, and the wire feeding speed is between 0.5 and 2 mm / s; and the duration of a single welding process does not exceed 10 seconds. If it exceeds, the welding should be performed again after the temperature of the weldment drops below 100°C.

8. The preparation method according to claim 7, characterized in that: The protective gas is an inert gas.

9. The preparation method according to claim 8, characterized in that: The inert gas is argon or helium.

10. Use of the high temperature resistant stirring magnet according to any one of claims 1 to 6 or the high temperature resistant stirring magnet obtained by the preparation method according to any one of claims 7 to 9 in the field of biomass hydrothermal liquefaction.

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