Silicon-potassium fertilizer and preparation method thereof
By mixing potassium fertilizer tailings and coal gangue with flux in a specific proportion and calcining them, silicon potassium fertilizer with microporous structure and sustained release properties was prepared, which solved the problem of unused potassium fertilizer tailings and coal gangue and improved resource utilization rate and water storage performance reduces environmental pollution.
Patent Information
- Application Number
- CN202411418748.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-11
- Publication Date
- 2024-12-13
AI Technical Summary
The tailings produced during the existing potassium fertilizer production process have not been fully utilized, resulting in waste of resources and environmental pollution; poor treatment of coal gangue also occupies land and is seriously polluted.
Potassium fertilizer with microporous structure and sustained release properties were prepared by crushing and high-temperature calcining using specific proportions of potassium fertilizer, gangue and flux.
The prepared silicon potassium fertilizer has a low silica content, and the release rate of potassium and silicon elements is slow, which improves resource utilization and has good water storage performance, solving the problems of traditional potassium fertilizer resource loss and environmental pollution.
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Figure CN119118738A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of preparing potash fertilizers, and in particular relates to silicon-potash fertilizers and a preparation method thereof. Background Art
[0002] Salt lake potash refers to salt lake sediments or brine resources rich in potash minerals, which mainly exist in closed basins in arid or semi-arid areas. Due to long-term evaporation, the salt in the brine of these salt lakes continues to concentrate, eventually forming deposits of various salt minerals. Salt lake potash is one of the important resources, mainly used for the production of potash fertilizers in agriculture, and can also be used in industries and food processing. After the potash fertilizer production process, salt lake potash will produce a large amount of tailings, which contain potash salts that have not been fully extracted. These tailings are usually piled up or directly abandoned and are not fully utilized.
[0003] A large amount of solid waste is generated during the mining, washing and other processing of coal, among which the most important waste is coal gangue. Coal gangue refers to the rock part extracted from the coal seam during the coal mining process. It usually contains high ash content and low calorific value and is not suitable for direct use as fuel. The treatment and utilization of coal gangue is an important environmental issue. The coal gangue currently produced is usually piled up and cannot be effectively utilized, which not only occupies a large amount of land, but also easily causes environmental pollution. Summary of the invention
[0004] In order to solve all or part of the above technical problems, the present invention provides the following technical solutions:
[0005] One of the purposes of the present invention is to provide a method for preparing silicon-potassium fertilizer, the preparation method comprising:
[0006] Providing a first material containing uniformly mixed potash tailings, coal gangue and flux, wherein the mass ratio of potash tailings to coal gangue in the first material is 0.5-1:1, and the mass ratio of the total mass of the potash tailings and coal gangue to the flux is 1:0.2-0.3, wherein the flux comprises hydroxides, carbonates and sulfates in a mass ratio of 1-5:2-1:16-2;
[0007] Crushing the first material to form a second material;
[0008] The second material is subjected to high temperature calcination treatment to form silicon-potassium fertilizer.
[0009] The present invention finds that by using a certain mass ratio of hydroxide, carbonate and sulfate as a mixed flux, the prepared silicon-potassium fertilizer is a sodium potassium nepheline phase, has a low silicon dioxide content, and contains a rich microporous structure. The silicon-potassium fertilizer exhibits good silicon and potassium slow-release characteristics and water storage capacity.
[0010] In some embodiments, the hydroxide includes one or more combinations of potassium hydroxide, sodium hydroxide, and magnesium hydroxide; the carbonate includes one or more combinations of sodium carbonate, potassium carbonate, and magnesium carbonate; the sulfate includes one or more combinations of sodium sulfate, potassium sulfate, and magnesium sulfate.
[0011] In some embodiments, the particle size of the second material is 100-300 μm.
[0012] In some embodiments, the process conditions of the high temperature calcination treatment include: a temperature of 800-1100° C. and constant temperature calcination for more than 4 hours. Preferably, the calcination time is 4-6 hours.
[0013] In some embodiments, the potassium content in the potash fertilizer tailings is 8.50-12.00wt%, the magnesium content is 8.50-10.00wt%, and the chlorine content is 50.00-52.00wt%.
[0014] In some embodiments, the coal gangue contains 20.20-27.00wt% silicon, 10.00-13.00wt% aluminum, 3.20-4.50wt% iron, 1.5-3.00wt% potassium and 1.20-2.00wt% magnesium.
[0015] A second object of the present invention is to provide a silicon-potassium fertilizer, which is prepared according to any of the methods described above.
[0016] In some embodiments, the silicon-potassium fertilizer is a sodium potassium nepheline phase, wherein the SiO2 content is less than 10wt%. The sodium potassium nepheline phase is conducive to the slow release of silicon and potassium, and the low SiO2 content does not affect the dissolution of silicon.
[0017] In some embodiments, the silicon-potassium fertilizer has a porous structure with a pore volume of 4.3588 m 2 / g or more (preferably 4.3588 to 7.6545 m 2 / g), of which micropores account for more than 45% of the total pore volume.
[0018] In some embodiments, the potassium content of the silicon-potassium fertilizer is 6.0-7.0wt%, and the silicon content is 20.0-22.0wt%.
[0019] In some embodiments, the potassium and silicon elements in the silicon-potassium fertilizer can be continuously dissolved within 7 days. In some embodiments, the potassium and silicon elements in the silicon-potassium fertilizer can be continuously dissolved within 2 days. In some embodiments, the potassium and silicon elements in the silicon-potassium fertilizer can be continuously dissolved within 24 hours. Compared with conventional potash fertilizers, the silicon-potassium fertilizer provided by the present invention has a slow-release property.
[0020] In some embodiments, the water storage rate of the silicon-potassium fertilizer after being soaked in water for 15 days is above 44.4%.
[0021] Compared with the prior art, the present invention has at least the following beneficial effects: the present invention utilizes potash fertilizer tailings and coal gangue as raw materials, and prepares a silicon-potassium fertilizer under the condition of adding a mixed flux in a certain mass proportion. The obtained silicon-potassium fertilizer is mainly sodium potassium nepheline phase, and its solubility is lower than that of existing potash fertilizers (such as potassium chloride, potassium sulfate, soft potassium magnesium alum, etc.), and it has a rich microporous structure; the release rate of potassium and silicon elements in the silicon-potassium fertilizer is relatively slow, and it has a sustained release performance, which solves the problem that the potassium in traditional silicon-potassium fertilizers is released too quickly, resulting in rapid loss of potassium resources and low utilization rate, and it also has good water storage performance. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0023] Figure 1 It is a schematic diagram of a process for preparing silicon-potassium fertilizer using potash fertilizer tailings and coal gangue as raw materials in one embodiment of the present invention;
[0024] Figure 2 is a SEM image of the silicon-potassium fertilizer prepared in Example 3 of the present invention;
[0025] Figure 3 This is the XRD diffraction pattern of the silicon-potassium fertilizer prepared in Example 3 of the present invention. DETAILED DESCRIPTION
[0026] The technical solution of the present invention is described in detail below in conjunction with specific embodiments so that those skilled in the art can better understand and implement the technical solution of the present invention. The specific functional details disclosed herein should not be interpreted as limiting, but only as the basis for the claims and as a representative basis for teaching those skilled in the art to adopt the present invention in different ways in any appropriate detailed embodiment.
[0027] Unless otherwise specified, the raw materials and reagents used in the present invention are all commercially available.
[0028] Example 1
[0029] This embodiment provides a potash fertilizer prepared using potash fertilizer tailings and coal gangue and a preparation method thereof:
[0030] The composition of the potash fertilizer tailings used in this embodiment is shown in Table 1:
[0031] Table 1 Chemical composition of potash fertilizer tailings of Example 1
[0032] element <![CDATA[K + ]]> <![CDATA[Mg 2+ ]]> <![CDATA[Cl - ]]> <![CDATA[H2O]]> Content / wt% 8.50 8.50 50.00 25.0
[0033] The composition of the coal gangue used in this embodiment is shown in Table 2:
[0034] Table 2 Chemical composition of coal gangue of Example 1
[0035] element Si Al Fe K Mg Content / wt% 20.20 10.00 3.20 1.5 1.20
[0036] The process flow of preparing silicon-potassium fertilizer in this embodiment is as follows Figure 1 As shown, the specific steps include:
[0037] The potash tailings (S1) and the coal gangue (S2) are uniformly mixed in a mass ratio of 0.5:1 to form a mixture (S3); a flux is added in a mass ratio of the mixture to the flux of 1:0.2, wherein the flux is sodium hydroxide, sodium carbonate and sodium sulfate in a mass ratio of 1:2:16, thereby forming a first material (S4);
[0038] The first material is placed in a crusher and crushed to form a second material with a particle size of about 100 μm;
[0039] The crushed second material is calcined at a high temperature of 800.0°C for 4 hours. After the calcination is completed, the calcined product is taken out and the obtained product is cooled to room temperature to obtain silicon-potassium fertilizer (S5).
[0040] XRD and BET characterization tests were performed on the silicon-potassium fertilizer prepared in this example, showing that it was composed of sodium potassium nepheline phase, with a SiO2 content of only 3.5wt% and a pore volume of 7.6545m 2 / g, rich in pores, the pores contained are mainly micropores, and micropores account for 46.9% of the total pore volume.
[0041] This example also tests the potassium, silicon content and water storage rate of the silicon-potassium fertilizer prepared above. The test method is to take 1.0g of silicon-potassium fertilizer, dilute it with water in a 1000mL volumetric flask, and take water samples regularly for elemental analysis. The potassium and silicon dissolution rates at different times are shown in Table 3, and the water storage rate of the silicon-potassium fertilizer is shown in Table 4.
[0042] Table 3 Potassium and silicon dissolution rates of silicon-potassium fertilizers of this embodiment at different times
[0043]
[0044] Conventional potash fertilizers in the prior art usually dissolve quickly, and when placed in water, they will all dissolve within a few minutes. However, as shown in Table 1, the potassium and silicon elements in the silicon-potash fertilizer prepared in this embodiment dissolve slowly, and can be continuously dissolved within 24 hours. The dissolution rate fluctuates from 1 to 14 days, indicating that the release of potassium and silicon has not reached equilibrium, and there is still a continuous dissolution phenomenon in the last few days.
[0045] Table 4 Water storage rate of silicon-potassium fertilizer obtained in this embodiment
[0046]
[0047] As shown in Table 4, the silicon-potassium fertilizer prepared in this embodiment has almost no water storage capacity after being soaked in water for 1 day, the water storage rate after being soaked in water for 7 days is about 10.0%, and the water storage rate after being soaked in water for 15 days is 60.0%. Its water storage capacity comes from its rich microporous structure, which can "store" water when water resources are abundant, and release water to alleviate the water shortage problem of plants when the external environment is short of water.
[0048] Example 2
[0049] This embodiment provides a potash fertilizer prepared using potash fertilizer tailings and coal gangue and a preparation method thereof:
[0050] The composition of the potash fertilizer tailings used in this embodiment is shown in Table 5:
[0051] Table 5 Chemical composition of potash fertilizer tailings of Example 2
[0052] element <![CDATA[K + ]]> <![CDATA[Mg 2+ ]]> <![CDATA[Cl - ]]> <![CDATA[H2O]]> Content / wt% 12.00 10.00 52.00 27.0
[0053] The composition of the coal gangue used in this embodiment is shown in Table 2
[0054] Table 6 Chemical composition of coal gangue of Example 2
[0055] element Si Al Fe K Mg Content / wt% 27.00 13.00 4.50 3.00 2.00
[0056] The preparation method specifically comprises the following steps:
[0057] The potash tailings and coal gangue are uniformly mixed in a mass ratio of 1:1 to form a mixture; a flux is added in a mass ratio of the mixture to the flux of 1:0.3, wherein the flux is sodium hydroxide, sodium carbonate and sodium sulfate in a ratio of 5:1:2, thereby forming a first material;
[0058] The first material is placed in a crusher and crushed to form a second material with a particle size of about 300 μm;
[0059] The second material obtained by crushing is calcined at high temperature, the calcination temperature is 1100.0°C, and the insulation time is 4.5h. After the calcination is completed, the calcined product is taken out and the obtained product is cooled to room temperature to obtain silicon-potassium fertilizer.
[0060] XRD and BET characterization tests were performed on the silicon-potassium fertilizer prepared in this example, showing that it was composed of sodium potassium nepheline phase, with a SiO2 content of 10wt% and a pore volume of 4.3588m 2 / g, and the pores contained are mainly micropores, accounting for about 45.0% of the volume.
[0061] This example also tests the potassium and silicon contents and water storage rate of the silicon-potassium fertilizer prepared above. The potassium and silicon dissolution rates at different times are shown in Table 7, and the water storage rate of the silicon-potassium fertilizer is shown in Table 8.
[0062] Table 7 Potassium and silicon dissolution rates of silicon-potassium fertilizers of this embodiment at different times
[0063]
[0064] Table 8 Water storage rate of silicon-potassium fertilizer prepared in this example
[0065]
[0066] As shown in Table 8, the silicon-potassium fertilizer prepared in this embodiment has almost no water storage capacity after being soaked in water for 1 day, the water storage rate after being soaked in water for 7 days is about 8.30%, and the water storage rate after being soaked in water for 15 days is about 44.4%.
[0067] Example 3
[0068] This embodiment provides a potash fertilizer prepared using potash fertilizer tailings and coal gangue and a preparation method thereof:
[0069] The composition of the potash fertilizer tailings used in this embodiment is shown in Table 9:
[0070] Table 9 Chemical composition of potash fertilizer tailings of Example 3
[0071]
[0072]
[0073] The composition of the coal gangue used in this embodiment is shown in Table 10:
[0074] Table 10 Chemical composition of coal gangue of Example 3
[0075] element Si Al Fe K Mg Content / wt% 23.5 12.2 4.00 2.50 1.70
[0076] The preparation method specifically comprises the following steps:
[0077] The potash tailings and coal gangue are uniformly mixed in a mass ratio of 0.65:1 to form a mixture; a flux is added in a mass ratio of the mixture to the flux of 1:0.2, wherein the flux is sodium hydroxide, sodium carbonate and sodium sulfate in a mass ratio of 3:1.5:8 to form a first material;
[0078] The first material is placed in a crusher and crushed to form a second material with a particle size of about 200 μm;
[0079] The second material obtained by crushing is calcined at high temperature, the calcination temperature is 900.0°C, and the insulation time is 4.1h. After the calcination is completed, the calcined product is taken out and the obtained product is cooled to room temperature to obtain silicon-potassium fertilizer.
[0080] XRD and BET characterization tests were performed on the silicon-potassium fertilizer prepared in this example, showing that it was composed of sodium potassium nepheline phase, with a SiO2 content of only 8.74wt% and a pore volume of 5.9874m 2 / g, and the pores contained are mainly micropores, accounting for 48.5% of the volume.
[0081] This example also tests the potassium and silicon contents and water storage rate of the silicon-potassium fertilizer prepared above. The potassium and silicon dissolution rates at different times are shown in Table 11, and the water storage rate of the silicon-potassium fertilizer is shown in Table 12.
[0082] Table 11 Potassium and silicon dissolution rates of silicon-potassium fertilizers of this embodiment at different times
[0083]
[0084] Table 12 Water storage rate of silicon-potassium fertilizer prepared in this embodiment
[0085]
[0086] As shown in Table 12, the silicon-potassium fertilizer prepared in this embodiment has almost no water storage capacity after being soaked in water for 1 day, the water storage rate after being soaked in water for 7 days is 9.10%, and the water storage rate after being soaked in water for 15 days is about 50.0%.
[0087] Figure 1 It is a schematic diagram of a process for preparing silicon-potassium fertilizer using potash fertilizer tailings and coal gangue as raw materials in one embodiment of the present invention; Figure 2 is a SEM image of the silicon-potassium fertilizer prepared in Example 3 of the present invention; Figure 3 This is the XRD diffraction pattern of the silicon-potassium fertilizer prepared in Example 3 of the present invention.
[0088] Comparative Example 1
[0089] The only difference between Comparative Example 1 and Example 1 is that the flux is sodium hydroxide and sodium carbonate in a mass ratio of 1:2. It is found that the silicon dioxide content in the obtained product reaches 30.0wt%. The generation of a large amount of silicon dioxide will make silicon difficult to release.
[0090] Comparative Example 2
[0091] The only difference between Comparative Example 2 and Example 1 is that the flux uses sodium hydroxide and sodium sulfate in a mass ratio of 1:16. It is found that the silicon dioxide in the obtained product accounts for 25.0wt%. The generation of a large amount of silicon dioxide will make silicon difficult to release.
[0092] Comparative Example 3
[0093] The only difference between Comparative Example 3 and Example 1 is that the flux is sodium carbonate and sodium sulfate in a mass ratio of 2:16. It is found that 4.5 wt% of magnesium oxide is generated in the product, which is not conducive to biological growth.
[0094] Comparative Example 4
[0095] The only difference between Comparative Example 4 and Example 1 is that only sodium hydroxide is used as the flux, and it is found that 11.5 wt % potassium chloride is generated in the product. The generation of more potassium chloride will lead to a faster release rate of potassium.
[0096] Comparative Example 5
[0097] The difference between Comparative Example 5 and Example 1 is that sodium carbonate is used as the flux, and it is found that 4.7wt% of potassium chloride and 21.5wt% of silicon dioxide are generated in the product. The generation of more potassium chloride will lead to a faster release rate of potassium, and the generation of more silicon dioxide will make silicon difficult to release.
[0098] Comparative Example 6
[0099] The difference between Comparative Example 6 and Example 1 is that only sulfate is used as the flux, and it is found that 4.3 wt % potassium sulfate is generated in the product, resulting in a faster release rate of potassium.
[0100] The various aspects, embodiments, features and examples of the present invention should be considered as illustrative in all aspects and are not intended to limit the present invention, the scope of the present invention is defined only by the claims. Other embodiments, modifications and uses will be apparent to those skilled in the art without departing from the spirit and scope of the claimed invention.
[0101] In addition, the inventors of this case also referred to the aforementioned embodiments and conducted experiments with other raw materials, process operations, and process conditions described in this specification, and obtained relatively ideal results.
[0102] Although the present invention has been described with reference to illustrative embodiments, it will be appreciated by those skilled in the art that various other changes, omissions and / or additions may be made without departing from the spirit and scope of the present invention and that the elements of the embodiments may be replaced by substantial equivalents. In addition, many modifications may be made without departing from the scope of the present invention to adapt specific circumstances or materials to the teachings of the present invention. Therefore, it is not intended herein to limit the present invention to the disclosed specific embodiments for performing the present invention, but it is intended that the present invention will include all embodiments within the scope of the appended claims. In addition, unless specifically stated, any use of the terms first, second, etc. does not indicate any order or importance, but rather uses the terms first, second, etc. to distinguish one element from another.
Claims
1. A method for preparing silicon-potassium fertilizer, characterized in that: include: Providing a first material containing uniformly mixed potash tailings, coal gangue and flux, wherein the mass ratio of potash tailings to coal gangue in the first material is 0.5-1:1, and the ratio of the total mass of the potash tailings and coal gangue to the mass of the flux is 1:0.2-0.3, wherein the flux comprises hydroxides, carbonates and sulfates in a mass ratio of 1-5:2-1:16-2; Crushing the first material to form a second material; The second material is subjected to high temperature calcination treatment to form silicon-potassium fertilizer.
2. The method according to claim 1, characterized in that: The hydroxide includes one or more combinations of potassium hydroxide, sodium hydroxide, and magnesium hydroxide; the carbonate includes one or more combinations of sodium carbonate, potassium carbonate, and magnesium carbonate; and the sulfate includes one or more combinations of sodium sulfate, potassium sulfate, and magnesium sulfate.
3. The method according to claim 1, characterized in that: The particle size of the second material is 100-300 μm.
4. The method according to claim 1, characterized in that: The process conditions of the high temperature calcination treatment include: a temperature of 800-1100° C. and constant temperature calcination for more than 4 hours.
5. The method according to claim 1, characterized in that: The potassium content of the potash fertilizer tailings is 8.50-12.00 wt %, the magnesium content is 8.50-10.00 wt %, and the chlorine content is 50.00-52.00 wt %.
6. The method according to claim 1, characterized in that: The coal gangue contains 20.20-27.00 wt % silicon, 10.00-13.00 wt % aluminum, 3.20-4.50 wt % iron, 1.5-3.00 wt % potassium and 1.20-2.00 wt % magnesium.
7. A silicon-potassium fertilizer, characterized in that: It is prepared according to the method described in any one of claims 1 to 6.
8. The silicon-potassium fertilizer according to claim 7, characterized in that: The silicon-potassium fertilizer is a sodium potassium nepheline phase, wherein the SiO2 content is less than 10wt%; And / or, the silicon-potassium fertilizer has a porous structure with a pore volume of 4.3588m 2 / g or more, of which micropores account for more than 45% of the total pore volume.
9. The silicon-potassium fertilizer according to claim 7, characterized in that: The silicon-potassium fertilizer contains 6.0-7.0 wt % potassium and 20.0-22.0 wt % silicon.
10. The silicon-potassium fertilizer according to claim 8, characterized in that: The potassium and silicon elements in the silicon-potassium fertilizer can be continuously dissolved within 7 days; And / or, the water storage rate of the silicon-potassium fertilizer after being soaked in water for 15 days is above 44.4%.