Additive adding device for melting urea
By combining a double-swirling mixer and a mixing heater, rapid mixing and dissolution of molten urea and additives is achieved, solving the problem of high biuret content in compound fertilizer production, improving the quality of compound fertilizer, and simplifying equipment maintenance.
Patent Information
- Application Number
- CN202520139890.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-20
- Publication Date
- 2025-12-26
- Estimated Expiration
- 2035-01-20
AI Technical Summary
In current compound fertilizer production, long mixing time and high-temperature heating result in high biuret content, affecting the quality of compound fertilizer. This is especially true in the production of small-batch micronutrient compound fertilizers, where heat loss during mixing is severe, making it difficult to control the biuret content.
By using pressurized feeding and taking advantage of the fluid flow characteristics within the double swirling mixer, solid particles and molten liquid are mixed in a swirling motion. Combined with a mixing heater, this accelerates dissolution, eliminating the need for a traditional stirrer and achieving rapid dissolution.
It reduces biuret content, improves the quality of compound fertilizer, reduces the difficulty of equipment maintenance and cleaning, and ensures environmental friendliness.
Smart Images
Figure CN223717032U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to fertilizer production technical field, especially relates to an additive adding device for molten urea. BACKGROUND
[0002] In the current compound fertilizer industry field, there are many compound fertilizer manufacturing processes such as roller, high tower, all of which take molten urea as raw material, further increase some other chemicals (additives) as formula for production. For small batch production of trace element compound fertilizer product, the mixing is usually carried out by the way of feeding into the stirring tank by belt after weighing by load cell, in this production process, the material in the stirring process needs to be heated due to the long mixing time required and the influence on subsequent production process due to avoiding heat loss in the stirring process, long time stirring and high temperature heating of the material will promote the generation of biuret, thereby causing the quality of compound fertilizer product to decrease, specifically, the high temperature time process in the production of compound fertilizer will increase the content of biuret, and high biuret content will lead to seedling and root burning, generally, the biuret content is required to be below 2%, and the generation rate of biuret in 130 DEG C molten urea is about 0.065% per minute. SUMMARY
[0003] The utility model aims at overcoming the defects in the prior art, and provides an additive adding device for molten urea.
[0004] The above technical purpose of the utility model is realized by the following technical scheme:
[0005] An additive adding device for molten urea, including molten urea pipeline with molten urea pressurizing pump, the molten urea pressurizing pump is connected with urea import of double spiral flow mixer, the middle part of additive pipeline is connected with additive storage tank through first tee joint, the first end of additive pipeline is connected with compressed gas source, the last end of additive pipeline is connected with additive import of double spiral flow mixer, the bottom of double spiral flow mixer is equipped with material outlet, the urea import and additive import are all arranged in tangent direction with the inner wall of double spiral flow mixer.
[0006] The utility model has the advantages that: the utility model discloses abandoning the form of adding additives by stirring in the traditional technology, and adopts the form of pressure feeding, and utilizes the structure fluid flow characteristics, so that solid particles and molten liquid accelerate downward rotation (generate spiral flow) and realize mixing, the above-mentioned mode does not need to adopt the stirring mode, not only reduces the equipment maintenance and cleaning difficulty, but also realizes the accelerated dissolution between materials, the utility model can realize the rapid dissolution of additives, thereby reducing the content of biuret, and ensuring the quality of compound fertilizer.
[0007] Preferably, the double-rotation flow mixer comprises a top cylinder, a middle cylinder and a bottom cylinder arranged in sequence at the lower part of the top cylinder, an additive inlet arranged at one side of the top cylinder, a urea inlet arranged at one side of the middle cylinder, a material outlet arranged at the bottom of the bottom cylinder, and a flow mixer heater arranged between the middle cylinder and the bottom cylinder for heating the inside of the double-rotation flow mixer.
[0008] Preferably, the flow mixer heater comprises two heads arranged at two sides and connected with the outer wall of the double-rotation flow mixer, tube sheets arranged inside the heads, and tubes arranged between the two tube sheets.
[0009] Preferably, the top cylinder is provided with a gas discharge pipeline with a gas discharge valve.
[0010] A demister is arranged inside the top cylinder between the gas discharge pipeline and the additive inlet.
[0011] The diameter of the top cylinder is greater than that of the middle cylinder, the cross section of the upper cylinder is inclined, and the bottom cylinder is funnel-shaped.
[0012] Preferably, the material outlet is connected with a subsequent production unit, a second three-way pipe and a third three-way pipe are arranged between the material outlet and the subsequent production unit, the third end of the second three-way pipe is connected with a steam flushing pipeline, a first valve is arranged between the third three-way pipe and the subsequent production unit, the third end of the third three-way pipe is provided with a flushing water pipeline with a second valve, and the pipeline between the material outlet and the second three-way pipe is arranged in an inclined manner.
[0013] Preferably, a liquid level meter and a temperature sensor are arranged on the middle cylinder, and a pressure sensor is arranged on the top cylinder.
[0014] Preferably, a front bin valve and a fourth three-way pipe are arranged in sequence between the compressed gas source and the first three-way pipe, a rear bin valve is arranged between the first three-way pipe and the additive inlet, the third end of the fourth three-way pipe is connected with the inner top part of an additive storage tank through a discharging communication valve, and a feeding valve is arranged between the additive storage tank and the first three-way pipe.
[0015] The utility model has the following advantages:
[0016] 1. The utility model adopts a pressure feeding type pneumatic conveying mode to add powder trace elements (additives), and can run for a long time after one-time feeding, and the additive storage tank is refilled when the material level is insufficient; the above-mentioned mode can ensure stable pressure, so as to generate a rotational flow in the double-rotation flow mixer, so as to achieve the characteristics of promoting the full mixing and rapid dissolution of materials.
[0017] 2, The utility model discloses utilize the mixing of fluid's own flow characteristics, need not adopt the way of agitator to stir, alleviate the difficulty of equipment maintenance, cleaning. The mixed flow heater that sets up in the double spiral mixed flow ware adopts the heat exchanger of internal insertion column pipe, and the column pipe can realize the baffle itself, makes the molten liquid not easy crystallization and blockage on it; When equipment maintenance, can draw out from one side tube plate, and the column pipe 90 degrees pipe arrangement, and the pipe is easy to clean with brush.
[0018] 3, The double spiral mixed flow ware in the utility model is intrinsically mixed and separated for gas-liquid-solid three phases, combines the flow characteristics of fluid, and the solid particle and molten liquid accelerated downward rotation mixing can be quickly dissolved, and the gas phase is spirally upwards from the center of equipment to the top of double spiral mixed flow ware and is discharged by gas exhaust pipe; Further, the mixed flow heater is arranged between the middle cylinder and bottom cylinder, can heat the solid particle that is not dissolved and the molten liquid nearby, to realize the characteristics of additive accelerated dissolution.
[0019] 4, The double spiral mixed flow ware in the utility model contains gas-liquid-solid three phases, is pressure-bearing equipment, to maintain system stability, therefore the whole is airtight, this setting can guarantee that dust particle does not leak, thereby reach the characteristics of environmental friendly. BRIEF DESCRIPTION OF DRAWINGS
[0020] Figure 1 It is the structural schematic diagram of the utility model.
[0021] Figure 2 It is the position relation schematic diagram of urea inlet and the inner wall of double spiral mixed flow ware of the utility model.
[0022] Figure 3 It is the position relation schematic diagram of additive inlet and the inner wall of double spiral mixed flow ware of the utility model.
[0023] Figure 4 It is the position relation schematic diagram of mixed flow heater and double spiral mixed flow ware of the utility model.
[0024] In the above diagram:
[0025] 1, melt urea pressurized pump; 2, melt urea pipeline; 3, urea import; 4, additive storage tank; 5, compressed gas source; 6, additive import; 7, material export; 8, fourth three-way; 9, top cylinder; 10, upper cylinder; 11, middle cylinder; 12, bottom cylinder; 13, mixed flow heater; 14, head; 15, tube plate; 16, tube; 17, steam import pipeline; 18, condensate export pipeline; 19, gas discharge valve; 20, gas exhaust pipeline; 21, demister; 22, subsequent production unit; 23, steam flushing pipeline; 24, first valve; 25, second valve; 26, flushing water pipeline; 27, liquid level meter; 28, temperature sensor; 29, third three-way; 30, pressure sensor; 31, bin front valve; 32, bin rear valve; 33, discharging communication valve; 34, feeding valve; 35, first three-way; 36, second three-way. DETAILED DESCRIPTION
[0026] The technical solutions of the present application will be described clearly and completely in combination with specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.
[0027] REFERENCE Figures 1-4 The present application is an additive adding device for melt urea, which comprises a melt urea pipeline 2 with a melt urea pressurized pump 1, the melt urea pressurized pump 1 is connected with a urea import 3 of a double-rotation mixed flow device, a middle part of an additive pipeline is connected with an additive storage tank 4 through a first three-way 35, a first end of the additive pipeline is connected with a compressed gas source 5, and a last end of the additive pipeline is connected with an additive import 6 of the double-rotation mixed flow device; a bottom of the double-rotation mixed flow device is provided with a material export 7, and the urea import 3 and the additive import 6 are both arranged in a tangent direction with an inner wall of the double-rotation mixed flow device. The present application is suitable for adding other chemicals (additives) during the production of compound fertilizer, and the difference from the traditional technology is that: the present application adopts a form of pressure feeding, and the urea import and the additive import are both arranged in a tangent direction with the inner wall of the double-rotation mixed flow device to make gas-liquid-solid three items form rotation flow in the double-rotation mixed flow device, so that the feature of accelerated dissolution is achieved, the content of biuret can be reduced through rapid dissolution, and the quality of the compound fertilizer is improved; further, the above-mentioned feature can realize the non-setting of a stirring device, so that the difficulty of equipment maintenance and cleaning is reduced.
[0028] Further, the double-rotation flow mixer comprises a top cylinder 9, the lower part of the top cylinder 9 is sequentially provided with an upper cylinder 10, a middle cylinder 11 and a bottom cylinder 12; one side of the top cylinder 9 is provided with an additive inlet 6, one side of the middle cylinder 11 is provided with a urea inlet 3, the bottom of the bottom cylinder 12 is provided with a material outlet 7, and a flow heater 13 for heating the inside of the double-rotation flow mixer is arranged between the middle cylinder 11 and the bottom cylinder 12. In order to improve the efficiency of dissolving the additive in the urea melt, the flow heater is arranged between the middle cylinder and the bottom cylinder, which can heat the solid particles and the melt in the process of accelerating the downward rotation and mixing, so as to improve the dissolving efficiency. The flow heater can be in the form of electric heating, heat transfer oil heat exchange or steam heat exchange, which can be arranged in the inside of the double-rotation flow mixer or in the form of coil outside the double-rotation flow mixer. Preferably, the flow heater is arranged between the middle cylinder and the bottom cylinder, which is mainly used for heating the undissolved additive and the urea melt near the additive, so as to realize the characteristic of rapid dissolving.
[0029] Further, the flow heater 13 comprises two end covers 14 arranged on both sides and connected with the outer wall of the double-rotation flow mixer, the inside of the end cover 14 is provided with a tube sheet 15, and a tube row 16 is arranged between the two tube sheets 15; wherein, the one end cover 14 is provided with a steam inlet pipe 17 and a condensate outlet pipe 18. The flow heater in the utility model preferably adopts the above-mentioned internal insertion heat exchanger, the essence of which lies in that the tube row 16 and the end cover 14 constitute the tube side, and the outside of the tube row 16 constitutes the shell side. The tube row 16 itself has the baffling effect, and at the same time, the tube row can be supported and baffled by the baffling rod and the baffling ring in the middle of the tube row, so that the melt liquid is not easy to crystallize and block on the tube row. When the equipment is overhauled, the tube row can be pulled out from one side of the tube sheet, and the tube row is arranged at an angle of 90 degrees, so that the tubes can be easily cleaned by a brush.
[0030] Further, the top cylinder 12 is provided with a gas discharge pipe 20 provided with a gas discharge valve 19. The gas discharge pipe 20 can facilitate the discharge of gas, and the gas discharge valve 19 can maintain the pressure inside the double-rotation flow mixer. When the internal pressure is too high, the gas discharge valve 19 can be used for pressure relief, so as to realize the stable pressure inside the double-rotation flow mixer.
[0031] Further, the top cylinder 9 between the gas discharge pipe 20 and the additive inlet 6 is provided with a demister 21. The demister 21 can avoid liquid in the gas, which affects the subsequent operation of the gas, and can also reduce the loss of the urea melt.
[0032] Further, the diameter of the top cylinder 9 is larger than that of the middle cylinder 11, the upper cylinder 10 is in the shape of an inclined section, and the bottom cylinder 12 is in the shape of a funnel. The structure of the utility model is gradually reduced from top to bottom, which makes the space of solid phase and liquid phase gradually smaller, thereby increasing the contact probability between the additive and the molten urea solution, accelerating the rapid dissolution of the additive, and further, the funnel-shaped bottom cylinder 12 can facilitate the rapid discharge of the urea molten solution after the dissolution of the additive.
[0033] Further, the material outlet 7 is connected with the subsequent production unit 22, a second three-way pipe 36 and a third three-way pipe 29 are arranged between the material outlet 7 and the subsequent production unit 22, the third end of the second three-way pipe 36 is connected with the steam flushing pipeline 23, the first valve 24 is arranged between the third three-way pipe 29 and the subsequent production unit 22, the third end of the third three-way pipe 29 is provided with a flushing water pipeline 26 with a second valve 25, and the pipeline between the material outlet 7 and the second three-way pipe 36 is arranged in an inclined manner. Through the above arrangement, the pipeline between the material outlet 7 and the third three-way pipe 29 can be conveniently cleaned. When cleaning is needed, the steam flushing pipeline 23 can be opened to make steam enter the pipeline for cleaning, and the flushing water pipeline 26 can be used for discharge after cleaning.
[0034] Further, the liquid level meter 27 and the temperature sensor 28 are arranged on the middle cylinder 11, and the pressure sensor 30 is arranged on the top cylinder 9. Through the arrangement of the liquid level meter 27, the temperature sensor 28 and the pressure sensor 30, the liquid level, the temperature and the pressure in the double-rotation flow mixer can be monitored, the entering amount of the urea molten solution and the entering amount of the additive can be controlled by observing the liquid level, the entering amount of the steam in the tube bank 16 can be adjusted by monitoring the temperature to control the temperature of the material near the flow heater 13, and the opening time of the gas discharge valve 19 can be determined by monitoring the pressure.
[0035] Further, the compressed gas source 5 and the first three-way pipe 35 are sequentially provided with the front bin valve 31 and the fourth three-way pipe 8, the first three-way pipe 35 and the additive inlet 6 are provided with the rear bin valve 32, the third end of the fourth three-way pipe 8 is connected with the inner top of the additive storage tank 4 through the discharging communication valve 33, and the additive storage tank 4 and the first three-way pipe 35 are provided with the feeding valve 34. Through the above arrangement, the feeding amount of the additive can be controlled, that is, the discharging amount of the additive storage tank 4 can be controlled by the cooperation of the front bin valve 31, the discharging communication valve 33 and the feeding valve 34, and the cooperation between the front bin valve 31 and the rear bin valve 32 not only enables the additive to enter the double-rotation flow mixer, but also stabilizes the pressure of the gas phase in the double-rotation flow mixer, so that the system can be stably operated for a long time.
[0036] The working principle of the utility model discloses: the flow of molten urea is 15t / h, the temperature is about 133 DEG C, the source pressure is about 0.05MPaG, the additive is potassium sulfate powder 75kg / h, the flow of 0.3MPaG compressed air is 2.82m 3 / h;The urea molten liquid with the temperature of about 133 DEG C and the pressure of 0.05MPaG from the upstream process is raised to 0.15MPaG by molten urea pressure pump 1 and is sent into the double spiral flow mixer by urea inlet 3 and flows downward in the cylinder under the action of inertial centrifugal force;Meanwhile, the additive in additive storage tank 4 can be fed into the double spiral flow mixer every 3 minutes, and the additive is transported into the double spiral flow mixer by additive inlet 6 through compressed air, and under the action of inertial centrifugal force, the potassium sulfate powder uniformly rotates and flows downward to the middle cylinder 11 and rotates in the same direction with the molten urea in the middle cylinder 11;The process of potassium sulfate powder feeding can adopt pulse control mode, before compressed air, the bin front valve 31 and the bin rear valve 32 are closed, after the action is completed, the discharge communication valve 33 is opened to release pressure, then the feeding valve 345S is opened to discharge, 5S later, the discharge communication valve 33 is closed, and after completion, the bin front valve 31 and the bin rear valve 32 are opened, and the action time of a set of pulse program control is 20S;Because there are processes such as pressure reduction and dissolution in the double spiral flow mixer, the medium needs to be heated, and in order to accelerate mixing, the inner diameter of the middle cylinder 11 of the double spiral flow mixer is small, and it is not convenient to set the inner coil pipe for heating;Based on this, the utility model adopts the inner insertion type tube heat exchanger for heating, the inner diameter of the heat exchanger is 300mm (96 φ19*2 stainless steel heat exchange pipes are arranged in the heat exchanger), because the length of the tube is only 500mm, the temperature difference between the heated medium and the steam in the tube is small, and the expansion force of the tube is within the bearing range;In addition, the support of the tube adopts the baffle rod ring, the baffle ring is fixed on the tube plate through the pull rod, and the tube is arranged at 90 degrees;The heated medium can be more uniformly dissolved to become a phase, the molten liquid after dissolution in the bottom cylinder 12 is more uniformly rotated, and then is discharged from the material outlet 7;The gas separated in the double spiral flow mixer is discharged through the gas discharge valve 19 and the gas discharge pipeline 20, and a waste gas treatment device can be arranged subsequently.
[0037] Although the embodiments of the present application have been shown and described, it is to be understood that various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.
Claims
1. An additive adding device for molten urea, comprising a molten urea pipeline (2) with a molten urea pressurizing pump (1), characterized in that: The molten urea pressurized pump (1) is connected with the urea inlet (3) of the double-rotation flow mixer, the middle part of the additive pipeline is connected with the additive storage tank (4) through the first three-way pipe (35), the first end of the additive pipeline is connected with the compressed gas source (5), and the last end of the additive pipeline is connected with the additive inlet (6) of the double-rotation flow mixer. The bottom of the double-rotation flow mixer is provided with the material outlet (7), and the urea inlet (3) and the additive inlet (6) are arranged in a tangent direction with the inner wall of the double-rotation flow mixer.
2. The additive adding device for molten urea according to claim 1, characterized by: The double-rotation flow mixer comprises a top cylinder (9), and the lower part of the top cylinder (9) is sequentially provided with an upper cylinder (10), a middle cylinder (11) and a bottom cylinder (12). One side of the top cylinder (9) is provided with the additive inlet (6), one side of the middle cylinder (11) is provided with the urea inlet (3), the bottom of the bottom cylinder (12) is provided with the material outlet (7), and the middle cylinder (11) and the bottom cylinder (12) are provided with a flow mixer heater (13) for heating the inside of the double-rotation flow mixer.
3. The additive adding device for molten urea according to claim 2, characterized by: The flow mixer heater (13) comprises two heads (14) arranged on the two sides and connected with the outer wall of the double-rotation flow mixer, the inside of the head (14) is provided with a tube sheet (15), and the two tube sheets (15) are provided with a tube bank (16); wherein one of the heads (14) is provided with a steam inlet pipeline (17) and a condensate outlet pipeline (18).
4. The additive adding device for molten urea according to claim 2, characterized by: The top cylinder (9) is provided with a gas discharge pipeline (20) with a gas discharge valve (19).
5. The additive addition device for molten urea according to claim 4, characterized by: A demister (21) is arranged in the top cylinder (9) between the gas discharge pipeline (20) and the additive inlet (6).
6. The additive adding device for molten urea according to claim 2, characterized by: The diameter of the top cylinder (9) is greater than the diameter of the middle cylinder (11), the cross section of the upper cylinder (10) is inclined, and the bottom cylinder (12) is funnel-shaped.
7. The additive addition device for molten urea according to claim 1 or 2, characterized by: The material outlet (7) is connected with a subsequent production unit (22), a second three-way pipe (36) and a third three-way pipe (29) are arranged between the material outlet (7) and the subsequent production unit (22), the third end of the second three-way pipe (36) is connected with a steam flushing pipeline (23), a first valve (24) is arranged between the third three-way pipe (29) and the subsequent production unit (22), the third end of the third three-way pipe (29) is provided with a flushing water pipeline (26) with a second valve (25), and the pipeline between the material outlet (7) and the second three-way pipe (36) is arranged in an inclined manner.
8. The additive adding device for molten urea according to claim 2 or 6, characterized by: The middle cylinder (11) is provided with a liquid level meter (27) and a temperature sensor (28), and the top cylinder (9) is provided with a pressure sensor (30).
9. The additive injection apparatus for molten urea according to claim 1, characterized by: A warehouse front valve (31) and a fourth three-way pipe (8) are sequentially arranged between the compressed gas source (5) and the first three-way pipe (35), a warehouse rear valve (32) is arranged between the first three-way pipe (35) and the additive inlet (6), the third end of the fourth three-way pipe (8) is connected with the inner top of the additive storage tank (4) through a discharging communication valve (33), and a feeding valve (34) is arranged between the additive storage tank (4) and the first three-way pipe (35).