A pilot plant for a liquid water-soluble fertilizer

Abstract

This utility model discloses a pilot-scale apparatus for liquid water-soluble fertilizer, including a mixing tank. The mixing tank contains a stirring and scraping mechanism, which includes a central shaft located inside the mixing tank. A stirring rod is connected to the central shaft, and a mounting frame is connected to the central shaft. The mounting frame has a mounting groove inside, and a scraper is installed inside the mounting groove. Through holes are provided on the scraper and the mounting frame, and bolts are installed inside the through holes. One end of the bolt passes through the through hole and is connected to a nut. An anti-loosening washer is provided between the nut and the mounting frame. This utility model, by setting up a stirring and scraping mechanism consisting of a central shaft, a mounting frame, and a scraper inside the mixing tank, allows the scraper to move closely against the inner wall of the mixing tank as it rotates with the central shaft, promptly scraping away high-concentration materials, phosphate crystals, or trace element precipitates adhering to the tank wall, avoiding localized scaling and ensuring sufficient mixing of materials during the reaction process.

Description

Technical Field

[0001] This utility model relates to the field of water-soluble fertilizer technology, specifically to a pilot-scale device for liquid water-soluble fertilizer. Background Technology

[0002] Liquid water-soluble fertilizers have been widely used in modern agriculture in recent years due to their advantages such as high nutrient content, good solubility, and the ability to be integrated with irrigation systems for fertigation. In the research and development of liquid water-soluble fertilizers, pilot-scale equipment is a crucial link connecting laboratory trials with industrial production. Its role is to verify the feasibility of the formulation, optimize process parameters, evaluate equipment performance and product quality stability, and provide reliable data support for subsequent large-scale production.

[0003] In existing pilot-scale plants for liquid water-soluble fertilizers, one of the most critical process steps is the uniform mixing of various raw materials (such as nutrients like nitrogen, phosphorus, and potassium), a process typically relying on stirred tanks. However, in practical applications, existing devices still present several technical challenges: First, during mixing, high-concentration materials or materials containing phosphates or trace elements are prone to adhering to or crystallizing on the inner wall of the tank. Furthermore, the preparation of liquid water-soluble fertilizers often involves acid-base neutralization reactions, releasing harmful gases such as ammonia, nitrogen oxides, or acid mist. If these harmful gases are not promptly and effectively removed from the tank and treated, they will rapidly accumulate within the sealed or semi-sealed stirred tank, leading to a continuous increase in internal pressure. When the pressure exceeds the equipment's pressure-bearing limit, it may cause safety seal failure or even tank deformation or rupture, resulting in safety accidents. Currently, no effective solutions have been proposed to address these technical problems. Utility Model Content

[0004] In view of the problems in the related technologies, this utility model proposes a pilot-scale device for liquid water-soluble fertilizer to overcome the above-mentioned technical problems existing in the existing related technologies.

[0005] Therefore, the specific technical solution adopted by this utility model is as follows:

[0006] A pilot-scale apparatus for a liquid water-soluble fertilizer includes a mixing tank. The mixing tank is equipped with a stirring and scraping mechanism. The stirring and scraping mechanism includes a central shaft located inside the mixing tank, a stirring rod connected to the central shaft, and a mounting frame connected to the central shaft. The mounting frame has a mounting groove inside, and a scraper is installed inside the mounting groove. The scraper and the mounting frame have through holes, and a bolt is installed inside the through hole. One end of the bolt passes through the through hole and is connected to a nut. An anti-loosening washer is provided between the nut and the mounting frame.

[0007] Furthermore, anti-loosening washers are fitted onto the outside of the bolts.

[0008] Furthermore, the top of the mixing tank is equipped with a sealing cover, the central shaft is connected to the sealing cover through a bearing, the central shaft is connected to the output end of the reducer, and the input end of the reducer is connected to the drive motor.

[0009] Furthermore, the speed reducer and drive motor are mounted on the top of the sealing cover.

[0010] Furthermore, an exhaust port is connected to one side of the top of the mixing tank. The exhaust port is connected to an exhaust pipe, which is connected to an exhaust gas treatment system. A pressure sensor is connected inside the exhaust port, and a regulating valve is connected to the exhaust port.

[0011] Furthermore, the pressure sensor is electrically connected to the PLC controller, the PLC controller is electrically connected to the regulating valve, and the PLC controller is installed on the outside of the mixing tank.

[0012] Furthermore, the top of the mixing tank is provided with a hinge seat, which is hinged to the fixed frame. The top of the fixed frame is threaded with a screw rod, one end of which abuts against the sealing cover. A positioning block is connected below the sealing cover. The top of the mixing tank is provided with a positioning groove, and the positioning block matches the positioning groove.

[0013] Furthermore, a discharge pipe is connected to the top of the mixing tank.

[0014] The beneficial effects of this utility model are as follows:

[0015] (1) A stirring and scraping mechanism consisting of a central shaft, a mounting frame, and a scraper is installed inside the mixing tank. As the scraper rotates with the central shaft, it moves closely against the inner wall of the mixing tank, promptly scraping away high-concentration materials, phosphate crystals, or trace element precipitates adhering to the tank wall, avoiding local scaling and ensuring sufficient mixing of materials during the reaction process. The scraper is fixed in the mounting groove of the mounting frame by bolts and nuts. After the scraper has been used for a long time, it can be disassembled and replaced.

[0016] (2) By setting an exhaust port at the top of the mixing tank and connecting it to the waste gas treatment system through an exhaust pipe, harmful gases such as ammonia, nitrogen oxides, and acid mist generated during the acid-base neutralization reaction can be discharged in a timely manner, avoiding safety risks caused by pressure buildup inside the tank. A pressure sensor is installed inside the exhaust port and equipped with an adjustable valve. The pressure sensor monitors the pressure changes inside the tank in real time and transmits the signal to the PLC controller. The PLC controller automatically adjusts the valve opening according to the preset pressure threshold. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a front view of a pilot-scale apparatus for a liquid water-soluble fertilizer according to an embodiment of the present utility model;

[0019] Figure 2 This is a structural diagram of the internal structure of the mixing tank of a pilot-scale device for liquid water-soluble fertilizer according to an embodiment of the present invention;

[0020] Figure 3 This is a disassembly diagram of the sealing cover of a pilot-scale liquid water-soluble fertilizer device according to an embodiment of the present utility model;

[0021] Figure 4 This is a structural diagram of the central shaft of a pilot-scale device for liquid water-soluble fertilizer according to an embodiment of the present invention;

[0022] Figure 5 yes Figure 4 Enlarged diagram of point A in the middle.

[0023] In the picture:

[0024] 1. Mixing tank; 2. Mixing and scraping mechanism; 201. Central shaft; 202. Mixing rod; 203. Mounting bracket; 204. Mounting groove; 205. Scraper; 206. Through hole; 207. Bolt; 208. Nut; 209. Anti-loosening gasket; 3. Sealing cover; 4. Reducer; 5. Drive motor; 6. Exhaust port; 7. Exhaust pipe; 8. Pressure sensor; 9. Regulating valve; 10. PLC controller; 11. Hinge seat; 12. Fixing bracket; 13. Screw; 14. Positioning block; 15. Positioning groove; 16. Discharge pipe. Detailed Implementation

[0025] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0026] According to an embodiment of the present invention, a pilot-scale apparatus for liquid water-soluble fertilizer is provided.

[0027] like Figures 1-5As shown, the pilot-scale apparatus for liquid water-soluble fertilizer according to an embodiment of the present invention includes a mixing tank 1. A stirring and scraping mechanism 2 is provided inside the mixing tank 1. The stirring and scraping mechanism 2 includes a central shaft 201 located inside the mixing tank 1. A stirring rod 202 is connected to the central shaft 201. A mounting frame 203 is connected to the central shaft 201. A mounting groove 204 is provided inside the mounting frame 203. A scraper 205 is installed inside the mounting groove 204. The scraper 205 is made of a wear-resistant and acid / alkali-resistant non-metallic material (such as modified polytetrafluoroethylene PTFE or reinforced polypropylene). Through holes 206 are provided on the scraper 205 and the mounting frame 203. Bolts 207 are installed inside the through holes 206. One end of the bolt 207 passes through the through hole 206 and is connected to the nut 208. An anti-loosening washer 209 is provided between the nut 208 and the mounting bracket 203. The anti-loosening washer 209 is sleeved on the outside of the bolt 207. It can effectively prevent the bolt 207 from loosening or falling off under the vibration environment generated by the long-term operation of the equipment, significantly improving the reliability and safety of the scraper 205 connection, and avoiding equipment failure or product quality accidents caused by the scraper 205 falling off. The top of the mixing tank 1 is provided with a sealing cover 3. The central shaft 201 is connected to the sealing cover 3 through a bearing. The central shaft 201 is connected to the output end of the reducer 4. The input end of the reducer 4 is connected to the drive motor 5. The reducer 4 and the drive motor 5 are installed on the top of the sealing cover 3.

[0028] like Figures 1-4As shown, an exhaust port 6 is connected to one side of the top of the mixing tank 1. The exhaust port 6 is connected to an exhaust pipe 7, which is connected to a waste gas treatment system. The waste gas treatment system includes a spray tower and an activated carbon adsorption device. Harmful gases can be introduced into the spray tower, activated carbon adsorption device, and other environmental protection equipment through the exhaust pipe 7 for purification treatment, achieving emission standards and ensuring safe operation and environmental compliance. A pressure sensor 8 is connected inside the exhaust port 6. The pressure sensor 8 is a corrosion-resistant diaphragm pressure transmitter. A regulating valve 9 is connected to the exhaust port 6. The pressure sensor 8 is electrically connected to a PLC controller 10, and the PLC controller 10 is electrically connected to the regulating valve 9. Based on a preset safe pressure threshold (e.g., +50Pa to -100Pa), the PLC controller 10 automatically determines whether to open or close the regulating valve 9 to control the pressure inside the tank. The dynamic closed-loop control system uses a PLC controller 10 mounted on the outside of the mixing tank 1. A hinged seat 11 is located at the top of the mixing tank 1, hinged to a fixed frame 12. A screw 13 is threadedly connected to the top of the fixed frame 12, with one end of the screw 13 abutting against the sealing cover 3. A positioning block 14 is connected below the sealing cover 3. A positioning groove 15 is located at the top of the mixing tank 1, matching the positioning block 14 and the positioning groove 15, enabling rapid centering and positioning when the sealing cover 3 is closed. An inlet is located at the top of the sealing cover 3, with a top cover threadedly connected to it. The top cover is removable, opening during material feeding and tightening after feeding to ensure the system's airtightness during the reaction process. A discharge pipe 16 is connected to the bottom of the mixing tank 1, with a control valve on the discharge pipe 16 for smoothly discharging the prepared liquid water-soluble fertilizer after the pilot test.

[0029] To facilitate understanding of the above-mentioned technical solutions of this utility model, the working principle or operation method of this utility model in actual process will be described in detail below.

[0030] In actual use, the mixed raw materials are added into the mixing tank 1 through the inlet. Then, the drive motor 5 is started, which drives the central shaft 201 and the stirring rod 202 on it to rotate via the reducer 4. The stirring rod 202 pushes the liquid to form a complex flow pattern, ensuring that the materials are fully and evenly mixed. As the central shaft 201 rotates, the scraper 205 moves closely against the inner wall of the mixing tank 1, promptly scraping off high-concentration materials, phosphate crystals, or trace element precipitates adhering to the tank wall. As the reaction proceeds, harmful gases such as ammonia, nitrogen oxides, or acid mist may be generated. The pressure sensor 8 inside the exhaust port 6 monitors the pressure changes inside the tank in real time and transmits the data to the PLC controller 10. When the pressure inside the tank exceeds the set safety range (e.g., +50Pa to -100Pa), the PLC controller 10 automatically opens the regulating valve 9 to exhaust the gas when the pressure exceeds the upper limit. When the pressure is too low and there is a risk of backflow, the valve is closed to maintain a slight negative pressure balance. The harmful gases are guided to the waste gas treatment system through the exhaust pipe 7. First, the mixture passes through a spray tower where an alkaline solution neutralizes the acidic gas. Then, it enters an activated carbon adsorption device to further remove residual organic matter and odors. After mixing, the drive motor 5 is turned off to stop stirring. The control valve on the discharge pipe 16 is opened to discharge the prepared liquid water-soluble fertilizer into a storage tank. To ensure the accuracy of the next batch of experiments, the mixing tank 1 is thoroughly cleaned. This is done by removing the screw 13 at the top of the sealing cap 3, allowing for easy cleaning of the tank's interior and the stirring components. After cleaning, the sealing cap 3 can be reinstalled. The positioning block 14 on the sealing cap 3 is installed inside the positioning groove 15 to position the sealing cap 3. Then, the screw 13 is used to tighten it, ensuring even pressure on the sealing ring and achieving an airtight seal for future use.

[0031] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A pilot-scale apparatus for a liquid water-soluble fertilizer, characterized in that, The system includes a mixing tank (1), and a stirring and scraping mechanism (2) is provided inside the mixing tank (1). The stirring and scraping mechanism (2) includes a central shaft (201) located inside the mixing tank (1). A stirring rod (202) is connected to the central shaft (201). A mounting bracket (203) is connected to the central shaft (201). A mounting groove (204) is provided inside the mounting bracket (203). A scraper (205) is installed inside the mounting groove (204). A through hole (206) is provided on the scraper (205) and the mounting bracket (203). A bolt (207) is provided inside the through hole (206). One end of the bolt (207) passes through the through hole (206) and is connected to a nut (208). An anti-loosening washer (209) is provided between the nut (208) and the mounting bracket (203).

2. The pilot-scale apparatus for a liquid water-soluble fertilizer according to claim 1, characterized in that, The anti-loosening washer (209) is fitted on the outside of the bolt (207).

3. The pilot-scale apparatus for a liquid water-soluble fertilizer according to claim 1, characterized in that, The mixing tank (1) is equipped with a sealing cover (3) at the top. The central shaft (201) is connected to the sealing cover (3) through a bearing. The central shaft (201) is connected to the output end of the reducer (4). The input end of the reducer (4) is connected to the drive motor (5).

4. The pilot-scale apparatus for a liquid water-soluble fertilizer according to claim 2, characterized in that, The speed reducer (4) and drive motor (5) are mounted on the top of the sealing cover (3).

5. The pilot-scale apparatus for a liquid water-soluble fertilizer according to claim 1, characterized in that, The top side of the mixing tank (1) is connected to an exhaust port (6), which is connected to an exhaust pipe (7). The exhaust pipe (7) is connected to the exhaust gas treatment system. A pressure sensor (8) is connected inside the exhaust port (6), and a regulating valve (9) is connected to the exhaust port (6).

6. The pilot-scale apparatus for a liquid water-soluble fertilizer according to claim 5, characterized in that, The pressure sensor (8) is electrically connected to the PLC controller (10), the PLC controller (10) is electrically connected to the regulating valve (9), and the PLC controller (10) is installed on the outside of the mixing tank (1).

7. The pilot-scale apparatus for a liquid water-soluble fertilizer according to claim 1, characterized in that, The top of the mixing tank (1) is provided with a hinge seat (11), which is hinged to the fixed frame (12). The top of the fixed frame (12) is threaded with a screw (13), one end of which abuts against the sealing cover (3). A positioning block (14) is connected below the sealing cover (3). The top of the mixing tank (1) is provided with a positioning groove (15), and the positioning block (14) matches the positioning groove (15).

8. The pilot-scale apparatus for a liquid water-soluble fertilizer according to claim 1, characterized in that, The bottom of the mixing tank (1) is connected to a discharge pipe (16).

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