Production device for large-scale continuous preparation of potassium humate fertilizer from potassium feldspar and full resource utilization

Abstract

The invention discloses a production device for large-scale continuous production of potassium humate fertilizer from potassium feldspar and full-resource utilization. Comprising a wet pulping subsystem, a hydrothermal reaction subsystem, a flash evaporation filter pressing subsystem, a humic acid modified potash fertilizer preparation subsystem and a causticization and humic acid modified silicon-calcium fertilizer preparation subsystem, wherein the wet pulping subsystem is connected with the hydrothermal reaction subsystem through a high-pressure feeding pump; the hydrothermal reaction subsystem is connected with a feed port of the depressurization flash tower through the tower bottom of the tower-type delay reactor, the flash pressure filtration subsystem is connected with the humic acid modified potash fertilizer preparation subsystem through a solid phase outlet of a filter press A, and the flash pressure filtration subsystem is connected with the causticization and humic acid modified silicon-calcium fertilizer preparation subsystem through a liquid phase outlet of the filter press A; and a KOH outlet of a filter press B of the causticized and humic acid modified silicon-calcium fertilizer preparation subsystem is connected back to a wet mill of the wet pulping subsystem, so that a circular treatment system for large-scale continuous high-pressure hydrothermal preparation of the potassium feldspar and full-resource utilization is formed.

Description

1. Technical Field

[0001] The invention provides a large-scale continuous production of potassium humate fertilizer from potassium feldspar and a full resource utilization production device, and relates to the field of fine chemicals. 2. Background technology

[0002] Potassium is one of the three essential nutrients for crop growth. It can enhance the ability of crops to resist drought, cold, disease, salt and lodging, and has a significant effect on stable and high yields of crops. Therefore, almost every crop needs to be applied with appropriate amounts of potassium fertilizer. my country has a huge demand gap for potassium fertilizer, but due to the extremely scarce water-soluble potassium salt resources used as potassium fertilizer, its reserves are equivalent to about 450 million tons of K2O, accounting for only 2.647% of the world's total. As the world's largest potassium fertilizer demander, my country's external dependence is as high as 50%.

[0003] However, my country's water-insoluble potassium ore resources are extremely rich, with wide distribution, high quality, and easy mining. Among them, potassium feldspar is the most representative, with estimated reserves of more than 20 billion tons. Since potassium feldspar has a three-dimensional framework structure formed by Si-Al-O tetrahedrons, its chemical properties are extremely stable and it is almost not decomposed by other acids and alkalis except concentrated sulfuric acid and hydrofluoric acid at room temperature and pressure. Therefore, the key to extracting potassium salts is to efficiently decompose potassium feldspar and convert the water-insoluble potassium into water-soluble potassium compounds.

[0004] There are more than ten process methods for producing potassium fertilizer using potassium feldspar at home and abroad, namely low-temperature decomposition, hydrothermal decomposition, microbial decomposition, molten salt ion exchange, roasting, blast furnace smelting, high-temperature melting and microwave radiation, etc. However, there are some problems in technology and economy, such as single product, excessive energy consumption, serious environmental pollution, overly complicated production process, large amount of tailings residue, too strong alkalinity of potassium fertilizer, insufficient full resource utilization, etc. So far, there has been no large-scale industrial production. It is urgent to develop a universal production method and equipment for large-scale continuous high-pressure hydrothermal production of potassium feldspar to solve the problem of full resource utilization of potassium feldspar resources. 3. Summary of the invention

[0005] The invention aims to overcome the shortcomings of the existing potassium feldspar preparation technology for potassium fertilizer, and to invent a large-scale continuous potassium feldspar preparation of humic acid potassium fertilizer and full resource utilization production device. The invention prepares alkaline slurry by wet grinding KOH solution and potassium feldspar, strengthens hydrothermal reaction of the alkaline slurry in an electromagnetic pipeline reactor and a tower delayed reactor, performs steam heat recovery and slurry dilution flocculation filtration after hydrothermal reaction slurry separation by flash evaporation, and mixes the filter residue with humic acid for modification and granulation to produce long-acting slow-release potassium fertilizer, returns the KOH solution obtained by causticizing reaction of filtrate with lime to wet pulping, and mixes calcium silicate with humic acid for modification and granulation production, thereby solving the defects of low potassium extraction rate, too strong alkalinity of potassium fertilizer products, excessive energy consumption, serious environmental pollution, and failure to effectively utilize tailings residues in the original potassium feldspar hydrothermal method for preparing potassium fertilizer, and realizes large-scale clean and efficient full resource fertilizer utilization of potassium feldspar resources.

[0006] The technical solution of the present invention:

[0007] A large-scale continuous production device for humic acid potassium fertilizer and full resource utilization of potassium feldspar, wherein a crusher is connected to a wet mill to form a wet pulping subsystem, the weight ratio of KOH solution to potassium feldspar is 1.5-5:1, the concentration of KOH solution is 25wt%-45wt%, and the pulping temperature is less than 80°C; an electromagnetic pipeline reactor is connected to a tower delay reactor to form a hydrothermal reaction subsystem, the flow rate in the tube is 1-5 m / s, the reaction temperature is 200-350°C, the pressure is the saturated pressure at the reaction temperature, the reaction time is 1-900 seconds, the delayed reaction time is 30-240 minutes, and the potassium extraction rate is 95%-99.9%; the top of the pressure-reducing flash tower is connected to a heat exchanger, the bottom of the tower is connected to a filter press, and the condensate outlet of the heat exchanger is connected to a flocculation adding tank in front of the filter press A to form a flash evaporation and filtration subsystem, and the pressure at the top of the flash tower is normal pressure-30KPa; a mixed modified granulator is connected to a dryer 1 to form a humic acid modified potassium fertilizer preparation subsystem, and alkaline silicon The weight ratio of potassium aluminate filter residue to humic acid is 1:0.1-0.3; the causticizing reactor is connected to the mixed modification granulator through the filter press B, and then connected to the dryer 2 to form a causticizing and humic acid modified silicon calcium fertilizer preparation subsystem, and the molar ratio of alkaline calcium silicate filtrate to potassium and calcium of lime is 2:1-1.2; the wet pulping subsystem is connected to the hydrothermal reaction subsystem through a high-pressure feed pump, and the hydrothermal reaction subsystem is connected to the feed port of the pressure-reducing flash tower through the bottom of the tower delay reactor. The flash filtration subsystem is connected to the humic acid modified potassium fertilizer preparation subsystem through the solid phase outlet of filter press A, and the flash filtration subsystem is connected to the causticizing and humic acid modified silicon-calcium fertilizer preparation subsystem through the liquid phase outlet of filter press A, and the KOH outlet of filter press B of the causticizing and humic acid modified silicon-calcium fertilizer preparation subsystem is connected back to the wet mill of the wet pulping subsystem, forming a large-scale continuous high-pressure hydrothermal production of humic acid potassium fertilizer from potassium feldspar and a circulating treatment system for full resource utilization.

[0008] Among them, the electromagnetic heating tubular reactor is a tubular reactor in which, under the action of the electromagnetic heating controller, high-frequency alternating current generates an alternating magnetic field through the coil, and the tubular reactor wall and the internal self-mixing strengthening internal components generate eddy current self-heating, thereby achieving uniform heating, rapid temperature rise and hydrothermal reaction of the high-pressure alkaline slurry; the self-mixing strengthening internal components are regular packing type, X-cross plate type or spiral plate type.

[0009] The tower delayed reactor has a height-to-diameter ratio of 3-30:1, and has filler components, grid self-mixing components or an empty tower inside.

[0010] The flash tower is set to 1-6 levels, and the heat exchanger for flash high-temperature steam cooling is a fire-tube heat exchanger that is easy to clear.

[0011] The present invention will be described in detail with reference to embodiments. 4. Description of the drawings

[0012] Attached Figure 1 It is a schematic diagram of the device of the present invention.

[0013] Attached Figure 1 The following is a description of the drawings:

[0014] 1. Crusher 2. Wet grinder 3. High-pressure feed pump 4. Electromagnetic heating tubular reactor 5. Electromagnetic heating regulator 6. Tower delayed reactor 7. Flash tower 8. Heat exchanger 9. Flocculation adding tank 10. Filter press A 11. Mixing and modification granulator 1 12. Dryer 1 13. Causticizing reactor 14. Filter press B 15. Mixing and modification granulator 2 16. Dryer 2A, flocculant inlet B, lime inlet C, cold air inlet D, humic acid coated long-acting slow-release potash fertilizer E, humic acid coated long-acting slow-release silicon-calcium fertilizer outlet The process features of the present invention are described in detail below in conjunction with the drawings and embodiments. 5. Specific implementation methods

[0015] Example

[0016] A large-scale continuous production device for potassium feldspar humic acid potassium fertilizer and full resource utilization production device, wherein a crusher (1) is connected to a wet mill (2) to form a wet pulping subsystem, the weight ratio of KOH solution to potassium feldspar is 1.5-5:1, the concentration of KOH solution is 25wt%-45wt%, and the pulping temperature is less than 80°C; an electromagnetic pipeline reactor (4) is connected to a tower delay reactor (6) to form a hydrothermal reaction subsystem, the flow rate in the pipe is 1-5 m / s, the reaction temperature is 200-350°C, and the pressure is at the reaction temperature. The saturated pressure and reaction time are 1-900 seconds, the delayed reaction time is 30-240 minutes, and the potassium extraction rate is 95%-99.9%; the top of the pressure-reducing flash tower (7) is connected to a heat exchanger, the bottom of the tower is connected to a filter press A (10), and the condensate outlet of the heat exchanger (8) is connected to a flocculation adding tank in front of the filter press A (10) to form a flash evaporation and filtration subsystem, and the top pressure of the flash tower (7) is normal pressure-30KPa; the mixed modified granulator (11) is connected to a dryer 1 (12) to form a humic acid modified potassium fertilizer preparation subsystem, and the alkaline silicon aluminum The weight ratio of potassium silicate filter residue to humic acid is 1:0.1-0.3; the causticizing reactor (13) is connected to the mixing modification granulator (15) through the filter press B (14), and then connected to the dryer 2 (16) to form a causticizing and humic acid modified silicon calcium fertilizer preparation subsystem, and the molar ratio of the alkaline calcium silicate filtrate to the potassium and calcium of the lime is 2:1-1.2; the wet pulping subsystem is connected to the hydrothermal reaction subsystem through the high-pressure feed pump (3), and the hydrothermal reaction subsystem is connected to the pressure-reducing flash tower (7) through the bottom of the tower delay reactor (6) The flash filtration subsystem is connected to the feed inlet of the filter press A (10), the flash filtration subsystem is connected to the humic acid modified potassium fertilizer preparation subsystem through the solid phase outlet of the filter press A (10), the flash filtration subsystem is connected to the causticizing and humic acid modified silicon calcium fertilizer preparation subsystem through the liquid phase outlet of the filter press A (10), and the KOH outlet of the filter press B (14) of the causticizing and humic acid modified silicon calcium fertilizer preparation subsystem is connected back to the wet mill (2) of the wet pulping subsystem, forming a large-scale continuous high-pressure hydrothermal production of humic acid potassium fertilizer and a circulation treatment system for full resource utilization of potassium feldspar.

[0017] The electromagnetic heating tubular reactor (4) is a tubular reactor in which, under the action of the electromagnetic heating controller (5), high-frequency alternating current generates an alternating magnetic field through the coil, and the tubular reactor wall and the internal self-mixing strengthening internal components generate eddy current self-heating, thereby achieving uniform heating, rapid temperature rise and hydrothermal reaction of the high-pressure alkaline slurry; the self-mixing strengthening internal components are regular packing type, X-cross plate type or spiral plate type.

[0018] The tower delayed reactor (6) has a height-to-diameter ratio of 3-30:1, and has a filler component, a grid self-mixing component or an empty tower inside.

[0019] The flash tower (7) is set to 1-6 stages, and the heat exchanger (8) for flash high-temperature steam cooling is a fire-tube heat exchanger that is easy to clear.

[0020] The specific reaction conditions and experimental results are as follows:

[0021] (1) A 30 wt% KOH solution and a potassium feldspar less than 6 mm and containing 13% potassium are wet-ground into an alkaline ore slurry with a particle size of ≤60 μm at a weight ratio of 3:1 and a temperature of 45° C., and then subjected to a hydrothermal reaction in an electromagnetic pipeline reactor at a flow rate of 2 m / s and a temperature of 280° C. for 10 seconds, and then delayed for 50 minutes in a tower delay reactor to obtain a hydrothermal reaction slurry with a potassium extraction rate of 98%; the hydrothermal reaction slurry is flash-distilled and separated in a secondary flash tower, and steam is heat-exchanged with air and diluted and filtered, and the obtained potassium aluminosilicate and calcium silicate are respectively mixed, modified, granulated and dried by adding 10% biological brown-black humic acid to obtain a humic acid-coated long-acting slow-release potassium fertilizer product containing 28% potassium and 22% silicon and a humic acid-coated long-acting slow-release silicon-calcium fertilizer product containing 24% silicon, and the KOH solution is circulated, and 10% KOH needs to be supplemented.

[0022] (2) 35wt% KOH solution and potassium feldspar less than 6mm and containing 13% potassium are wet-ground into alkaline ore slurry with a particle size of ≤74μm at a weight ratio of 2.5:1 and a temperature of 60°C, and then subjected to hydrothermal reaction in an electromagnetic pipeline reactor at a flow rate of 3 m / s and a temperature of 290°C for 7 seconds, and then delayed reaction in a tower delay reactor for 60 minutes to obtain a hydrothermal reaction slurry with a potassium extraction rate of 99.5%; the hydrothermal reaction slurry is flash-separated in a secondary flash tower, steam heat-exchanged with air and diluted and filtered, and the obtained potassium aluminosilicate and calcium silicate are respectively mixed by adding 15% of mineral brown-black humic acid, modified, granulated and dried to obtain a humic acid-coated long-acting slow-release potassium fertilizer product containing 27% potassium and 20% silicon and a humic acid-coated long-acting slow-release silicon-calcium fertilizer product containing 24.2% silicon, and the KOH solution is circulated, and 9% KOH needs to be supplemented.

[0023] (3) 35 wt % KOH solution and potassium feldspar less than 6 mm and containing 13 % potassium are wet-ground into alkaline ore slurry with a particle size of ≤74 μm at a temperature of 60° C., and then subjected to hydrothermal reaction in an electromagnetic pipeline reactor at a flow rate of 3 m / s and a temperature of 290° C. for 7 seconds, and then delayed reaction in a tower delay reactor for 60 minutes to obtain a hydrothermal reaction slurry with a potassium extraction rate of 99.5%; the hydrothermal reaction slurry is flash-distilled in a secondary flash tower The obtained calcium silicate is mixed, modified, granulated and dried by adding 15% biological brown-black humic acid to obtain a humic acid-coated long-acting slow-release silicon-calcium fertilizer product containing 24.2% silicon. The KOH solution is circulated and 9% KOH needs to be supplemented. The obtained potassium aluminosilicate is reacted at a temperature of 65°C according to a carboxyl to methanol molar ratio of 2:1 to generate a potassium humate solution and a difficult aluminum silicate precipitate. The potassium humate solution is dried to obtain a potassium humate product containing 30% potassium.

[0024] The large-scale continuous production of humic acid potassium fertilizer and full resource utilization production device of potassium feldspar provided by the present invention is characterized by KOH in-situ wet grinding activation and electromagnetic heating pipeline high-pressure hydrothermal desiliconization, flash separation after enhanced hydrothermal desiliconization in a tower delayed reactor, separated steam heating air is used for product drying, and the potassium fertilizer and calcium silicon fertilizer desiliconized by alkali water are neutralized, modified and granulated by humic acid to obtain a universal long-acting slow-controlled fertilizer, the potassium extraction rate of potassium fertilizer prepared by the original potassium feldspar hydrothermal method is increased from 85% to more than 99%, the pH value of the potassium fertilizer product is reduced from 13 to 6-8, the energy consumption of electromagnetic heating is reduced by 30%, there is no dust and wastewater pollution, and large-scale clean and efficient full resource fertilizer utilization of potassium feldspar resources is realized.

Claims

1. A large-scale continuous production device for potassium humate fertilizer and full resource utilization using potassium feldspar, characterized in that The crusher is connected to the wet mill to form a wet pulping subsystem, the weight ratio of KOH solution to potassium feldspar is 1.5-5:1, the concentration of KOH solution is 25wt%-45wt%, and the pulping temperature is less than 80°C; the electromagnetic pipeline reactor is connected to the tower delay reactor to form a hydrothermal reaction subsystem, the flow rate in the tube is 1-5 m / s, the reaction temperature is 200-350°C, the pressure is the saturated pressure at the reaction temperature, the reaction time is 1-900 seconds, the delayed reaction time is 30-240 minutes, and the potassium extraction rate is 95%-99.9%; the top of the pressure-reducing flash tower is connected to a heat exchanger, the bottom of the tower is connected to a filter press, and the condensate outlet of the heat exchanger is connected to the flocculation addition tank in front of the filter press A to form a flash evaporation and filtration subsystem, and the pressure at the top of the flash tower is normal pressure-30KPa; the mixed modified granulator is connected to the dryer 1 to form a humic acid modified potash fertilizer preparation subsystem, and the weight ratio of alkaline potassium aluminosilicate filter residue to humic acid is The molar ratio of potassium and calcium of alkaline calcium silicate filtrate to lime is 2:1-1.2; the wet pulping subsystem is connected to the hydrothermal reaction subsystem through a high-pressure feed pump, the hydrothermal reaction subsystem is connected to the feed port of the pressure-reducing flash tower through the bottom of the tower-type delayed reactor, the flash filter press subsystem is connected to the humic acid modified potassium fertilizer preparation subsystem through the solid phase outlet of the filter press A, the flash filter press subsystem is connected to the causticizing and humic acid modified silicon calcium fertilizer preparation subsystem through the liquid phase outlet of the filter press A, and the KOH outlet of the filter press B of the causticizing and humic acid modified silicon calcium fertilizer preparation subsystem is connected back to the wet mill of the wet pulping subsystem, forming a large-scale continuous high-pressure hydrothermal preparation of humic acid potassium fertilizer and a circulation treatment system for full resource utilization of potassium feldspar.

2. The large-scale continuous production of potassium humate fertilizer and full resource utilization production device of potassium feldspar according to claim 1 is characterized in that The electromagnetic heating tubular reactor is a tubular reactor in which, under the action of an electromagnetic heating controller, high-frequency alternating current passes through a coil to generate an alternating magnetic field, and eddy current self-heating is generated on the tubular reactor wall and the internal self-mixing strengthening internal components. The self-mixing strengthening internal components are regular packing type, X-cross plate type or spiral plate type.

3. The large-scale continuous production of potassium humate fertilizer and full resource utilization production device of potassium feldspar according to claim 1 is characterized in that The tower delayed reactor has a height-to-diameter ratio of 3-30:1, and has filler components, grid self-mixing components or an empty tower inside.

4. The large-scale continuous production of potassium humate fertilizer and full resource utilization production device of potassium feldspar according to claim 1 is characterized in that The flash tower is set to 1-6 levels, and the heat exchanger for flash high-temperature steam cooling is a fire-tube heat exchanger that is easy to clear.

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