High-efficiency humic acid production device

Abstract

The utility model relates to humic acid production technical field, concretely for humic acid efficient production device, the humic acid efficient production device, including vertical integration reaction tower, coarse filter, coarse filter links with acid liquor preparation jar through nanofiltration purification device, and acid liquor preparation jar links with vertical integration reaction tower through pipeline, and the inside of vertical integration reaction tower is equipped with pretreatment section, reaction section, separation section, and pretreatment section, reaction section, separation section arrange from top to bottom in proper order. The device passes through the adoption vertical integration reaction tower, and the flow of material from pretreatment section to reaction section again to separation section is realized with gravity, cancels the mechanical conveying equipment such as conveyer belt, hoist, and the production continuity and continuous operation time are greatly improved.

Description

Technical Field

[0001] This utility model relates to the field of humic acid production technology, specifically to a high-efficiency humic acid production device. Background Technology

[0002] Humic acid production involves processes such as raw material pretreatment, sulfuric acid acidification and activation, solid-liquid separation, product drying, and waste acid / waste heat recovery. While existing technologies offer optimization solutions for individual stages, they suffer from significant overall deficiencies. In terms of system integration, core processes like pretreatment, reaction, and drying are fragmented into independent equipment. Materials require mechanical transport via conveyor belts and elevators. However, semi-dry humic acid is highly viscous and easily adheres to the equipment's inner walls, causing blockages. Frequent shutdowns for cleaning severely impact production continuity. Furthermore, the multi-equipment layout increases land occupation and pipeline complexity.

[0003] In terms of energy utilization, the existing equipment forms two independent heat loops. For example, the heat from the alkali preparation vessel is only used for raw material drying, and the heat from the reaction vessel is only used for the drying unit, without graded heat allocation. The high-grade heat (80-90℃) generated by the acidification reaction and the low-grade heat (60-70℃) generated by the alkali preparation are not matched to the corresponding demand. The high-grade heat is used for the low-demand raw material drying, resulting in an energy utilization rate of less than 60%, and additional heaters need to be started to supplement the energy consumption.

[0004] In the acid circulation stage, existing equipment only removes solid impurities through filtration, without treating metal ions (calcium, magnesium ions, etc.) and small organic molecules dissolved from the raw materials in the acid. After long-term circulation, these impurities continuously accumulate in the acid, which not only reduces the activation efficiency of sulfuric acid and the extraction rate of humic acid by 5-8%, but also leads to a decrease in the purity and uneven color of the final product, resulting in excessive impurity content and affecting the stability of product quality. Utility Model Content

[0005] In view of the shortcomings of the prior art, the purpose of this utility model is to provide a high-efficiency humic acid production device. By adopting a vertical integrated reaction tower, the material is transferred from the pretreatment section to the reaction section and then to the separation section by gravity, eliminating mechanical conveying equipment such as conveyor belts and elevators, which greatly improves the continuity of production and continuous operation time.

[0006] This utility model is achieved using the following technical solution: The aforementioned high-efficiency humic acid production device includes a vertical integrated reaction tower, a coarse filter, and an acid preparation tank connected to the coarse filter via a nanofiltration purification device. The acid preparation tank is connected to the vertical integrated reaction tower via a pipeline. The vertical integrated reaction tower is internally equipped with a pretreatment section, a reaction section, and a separation section, which are arranged sequentially from top to bottom.

[0007] The vertical integrated reaction tower is equipped with a negative pressure feeding port and an exhaust gas outlet at the top, a hot air inlet at the bottom of the pretreatment section, and an inclined guide plate inside the pretreatment section.

[0008] The reaction section is equipped with a stirring paddle driven by a stirring motor inside, and a heat exchange jacket is provided on the outside of the reaction section. An annular spray pipe is provided above the stirring paddle, and the acid preparation tank is connected to the annular spray pipe through a pipe.

[0009] The separation section is provided with a liquid phase outlet and a solid phase outlet at the bottom, and a filter plate is provided inside the separation section. The liquid phase outlet is located between the filter plate and the vertical wall of the separation section.

[0010] Vertical integrated reaction tower: It adopts a cylindrical tower body (diameter 1.2-1.5m, height 5-6m) and is divided into three sections from top to bottom: The pretreatment section has 3-4 layers of inclined guide plates (inclination angle 30°), a hot air inlet at the bottom and a tail gas outlet at the top, so as to realize the countercurrent contact between raw materials and hot air to complete pre-drying; The reaction section is wrapped with a heat exchange jacket on the outer wall, and is equipped with a stirring paddle (speed 180-220r / min) and annular spray pipes (orifice diameter 3mm, 8-10 spray nozzles evenly distributed) to ensure that the acid solution and raw materials are fully mixed; The separation section has a built-in 150-mesh filter plate, and a liquid phase outlet and a solid phase outlet at the bottom to achieve preliminary solid-liquid separation.

[0011] Nanofiltration purification device: It adopts an acid-resistant nanofiltration membrane (molecular weight cutoff 200-300 Da), operates at a pressure of 1.2-1.8 MPa, and can retain more than 90% of metal ions and small molecule organic impurities, ensuring the purity of circulating acid solution.

[0012] Pretreatment section: hot air temperature 70-80℃ (from heat recovery module), raw material residence time 15-20min, and raw material moisture content ≤10% after drying; Reaction section: sulfuric acid concentration 40-50% (from acid preparation tank), reaction temperature 80-90℃ (temperature controlled by heat exchange jacket), reaction time 30-40min, stirring speed 200r / min; Separation section: filtration pressure 0.2-0.3MPa, moisture content of wet solid phase after separation ≤60%, acid concentration of liquid phase 15-20%; Nanofiltration purification: operating temperature 25-35℃, membrane flux 15-20L / (m²) 2 •h), the impurity content of the purified acid solution is ≤0.5%.

[0013] The heat exchange jacket of the reaction section is connected to a flash dryer via a hot air heat exchanger. The solid phase outlet is connected to the flash dryer via a pipe. An electric heater is installed inside the flash dryer.

[0014] The liquid phase outlet is connected to a coarse filter via a pipeline, and the nanofiltration purification device is connected to a neutralization tank via a pipeline. An alkali solution preparation vessel is connected to the neutralization tank. The low-grade heat from the alkali solution preparation vessel is used for workshop heating.

[0015] The acid preparation tank is equipped with a replenishment port, and the hot air heat exchanger is connected to the hot air inlet via a pipe.

[0016] The working principle of this utility model is as follows: Humic acid feedstock enters the pretreatment section of the vertical integrated reaction tower through a negative pressure feed port. Under the action of the guide plate, it comes into countercurrent contact with hot air and falls into the reaction section after drying. At the same time, sulfuric acid in the acid preparation tank is sprayed in through the spray pipe and reacts fully with the feedstock under the action of the agitator. The heat of reaction is removed through the heat exchange jacket.

[0017] After the reaction, the slurry enters the separation section. The filtered wet solid phase is sent to a flash dryer for drying. The liquid waste acid is first filtered through a coarse filter to remove solid impurities, and then purified by a nanofiltration device to remove metal ions and organic matter. The purified dilute sulfuric acid is returned to the acid preparation tank, mixed with concentrated sulfuric acid, and recycled. The nanofiltration concentrate is sent to a neutralization tank for treatment to meet standards before being discharged.

[0018] The high-grade heat from the reaction section heats the air via a hot air heat exchanger. Part of the heat is sent to the pretreatment section for raw material drying, and the other part is sent to a flash dryer for finished product drying. An electric heater is used to supplement the heat. The low-grade heat generated by the alkali solution preparation kettle is used for workshop heating, achieving full utilization of energy.

[0019] Compared with the prior art, the beneficial effects of this utility model are: (1) By adopting a vertical integrated reaction tower, the material is transferred from the pretreatment section to the reaction section and then to the separation section by gravity, eliminating mechanical conveying equipment such as conveyor belts and elevators, which greatly improves the continuity of production and continuous operation time and reduces the material blockage rate.

[0020] (2) By constructing a heat cascade utilization system, the high-grade heat exported from the reaction section is used for the drying of raw materials in the pretreatment section and the drying of finished products in the flash dryer, and the low-grade heat from the alkali preparation kettle is used for workshop heating, which greatly improves the energy utilization rate.

[0021] (3) By adding a nanofiltration purification device in the acid circulation link, metal ions and small molecule organic impurities in the circulating acid are intercepted, which improves the purity of the acid and the quality of the product. The sulfuric acid activation efficiency is stable and the humic acid extraction rate is significantly improved. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of the high-efficiency humic acid production device of this utility model; In the diagram: 1. Vertical integrated reaction tower; 1A. Pretreatment section; 1B. Reaction section; 1C. Separation section; 2. Negative pressure feed port; 3. Flash dryer; 4. Heat exchange jacket for reaction section; 5. Hot air heat exchanger; 6. Coarse filter; 7. Nanofiltration purification device; 8. Acid preparation tank; 9. Alkali preparation kettle; 10. Neutralization tank; 11. Hot air inlet; 12. Tail gas outlet; 13. Stirring paddle; 14. Annular spray pipe; 15. Filter plate; 16. Liquid phase outlet; 17. Solid phase outlet; 18. Electric heater; 19. Liquid replenishment port. Detailed Implementation

[0023] To make the objectives and technical solutions of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings.

[0024] Example 1 like Figure 1 As shown, the high-efficiency humic acid production device includes a vertical integrated reaction tower 1, a coarse filter 6, and an acid preparation tank 8 connected to the coarse filter 6 via a nanofiltration purification device 7. The acid preparation tank 8 is connected to the vertical integrated reaction tower 1 via a pipeline. The vertical integrated reaction tower 1 has a pretreatment section 1A, a reaction section 1B, and a separation section 1C arranged sequentially from top to bottom. The top of the vertical integrated reaction tower 1 has a negative pressure feed port 2 and a tail gas outlet 12. The bottom of the pretreatment section 1A has a hot air inlet 11, and the interior of the pretreatment section 1A has an inclined guide plate. The interior of the reaction section 1B has a stirring paddle 13 driven by a stirring motor, and the outside of the reaction section 1B has a reaction section heat exchange jacket 4. Above the stirring paddle 13 is an annular spray pipe 14, and the acid preparation tank 8 is connected to the annular spray pipe 14 via a pipeline. The separation section 1C has a liquid phase outlet 16 and a solid phase outlet 17 at its lower part. A filter plate 15 is installed inside the separation section 1C, and the liquid phase outlet 16 is located between the filter plate 15 and the vertical wall of the separation section 1C. The reaction section heat exchange jacket 4 is connected to a flash dryer 3 via a hot air heat exchanger 5. The solid phase outlet 17 is connected to the flash dryer 3 via a pipe. An electric heater 18 is installed inside the flash dryer 3. The reaction section heat exchange jacket 4 is connected to the hot air heat exchanger 5 via a heat transfer oil pipe. The heat exchanger outlet is divided into two paths: one connects to the pretreatment section 1A of the reaction tower, and the other connects to the flash dryer 3. The liquid phase outlet 16 is connected to a coarse filter 6 via a pipe. The nanofiltration purification device 7 is connected to a neutralization tank 10 via a pipe. An alkali preparation vessel 9 is connected to the neutralization tank 10. The heat exchange jacket of the alkali preparation vessel 9 is connected to the workshop heating pipes, and the concentrated liquid outlet of the nanofiltration purification device 7 is connected to the neutralization tank 10. The acid preparation tank 8 is equipped with a replenishment port 19, and the hot air heat exchanger 5 is connected to the hot air inlet 11 through a pipe.

[0025] The above-mentioned high-efficiency humic acid production device includes the following steps during operation: (1) Humic acid raw material enters the pretreatment section 1A of the vertical integrated reaction tower 1 through the negative pressure feed port 2. Under the action of the guide plate, it comes into countercurrent contact with hot air and falls into the reaction section 1B after drying. At the same time, sulfuric acid in the acid preparation tank 8 is sprayed in through the annular spray pipe 14 and reacts fully with the raw material under the action of the stirring paddle 13. The heat of reaction is discharged through the heat exchange jacket 4 of the reaction section. (2) The slurry after reaction enters the separation section 1C. The filtered wet solid phase is sent to the flash dryer 3 for drying. The liquid phase waste acid first passes through the coarse filter 6 to remove solid impurities, and then passes through the nanofiltration purification device 7 to intercept metal ions and organic matter. The purified dilute sulfuric acid is returned to the acid preparation tank 8 and mixed with concentrated sulfuric acid for recycling. The nanofiltration concentrate is sent to the neutralization tank 10 for treatment to meet the standards before being discharged. (3) The high-grade heat from the reaction section 1B heats the air through the hot air heat exchanger 5. Part of the heat is sent to the pretreatment section 1A for raw material drying, and the other part is sent to the flash dryer 3 for finished product drying. The low-grade heat generated by the alkali preparation kettle 9 is used for workshop heating, realizing full utilization of energy.

Images