Urea catalytic hydrolysis ammonia production equipment

Abstract

The invention discloses urea catalytic hydrolysis ammonia production equipment, belongs to the technical field of urea hydrolysis, and solves the problems that in the prior art, the urea catalytic hydrolysis ammonia production equipment cannot be suitable for different application scenes, a solid medicament cannot be added on line, and a system is unstable in operation, the urea catalytic hydrolysis ammonia production equipment comprises a reaction kettle, a feeding port is formed in the middle of the reaction kettle, and a heating coil is arranged on the lower portion of one end of the reaction kettle; the heating coil is arranged on the inner side of the reaction kettle in a penetrating manner, water vapor circulates in the heating coil, and a catalyst adding mechanism is arranged on the outer wall of the reaction kettle. According to the invention, the cylinder is used for pushing the medicine shell, the medicine shell filled with a new catalyst is pushed into the inner side of the medicine adding pipe, and the medicine shell filled with an old catalyst is pushed out of the outer side of the medicine adding pipe, so that the replacement of the equivalent catalyst is realized, and the catalyst in the medicine shell is in a solid state, so that the online adding of the catalyst in different use scenes is improved; and in the upward moving process of the pushing head, the outward convex surface can move the medicine shell above along the radial direction of the medicine adding pipe, so that the reliable pushing of the pushing head is ensured.

Description

Technical Field

[0001] The present invention belongs to the technical field of urea hydrolysis, and more particularly, to an ammonia production device by catalytic hydrolysis of urea. Background Art

[0002] The urea catalytic hydrolysis technology has a wide range of applications in industrial applications, especially in flue gas denitrification systems. Through the ammonia production process by catalytic hydrolysis of urea, ammonia reducing agents can be stably provided for flue gas denitrification devices. This process has the advantages of rapid response, flexible layout, high system reliability, and low operating cost.

[0003] A catalyst online filling system for a urea catalytic hydrolysis reactor is disclosed in a Chinese patent document with the publication number CN220610288U. It includes a catalyst dissolution and filling tank, a urea catalytic hydrolysis reactor, a drain pipe, a filling pipe, a balance valve, and a balance pipe. The catalyst dissolution and filling tank is arranged at the upper end of the urea catalytic hydrolysis reactor, and the height difference between the catalyst dissolution and filling tank and the urea catalytic hydrolysis reactor is not less than one meter. The catalyst online filling system for the urea catalytic hydrolysis reactor involved in this utility model can add catalysts online during the normal pressurized operation of the catalytic hydrolysis reactor. The system adopts a height difference design to achieve the filling of catalyst solution by gravity. It has a simple structure and high reliability, and can ensure the uninterrupted and stable operation of the urea catalytic hydrolysis system.

[0004] However, the above patent can only complete the online addition of liquid catalysts and cannot complete the online addition of solid catalysts. The applicable range is relatively narrow and it is difficult to meet diverse usage scenarios. Summary of the Invention

[0005] The purpose of the present invention is to provide an ammonia production device by catalytic hydrolysis of urea that is applicable to different application scenarios, can add solid agents online, and has a stable system operation in view of the deficiencies of the existing technology.

[0006] In order to achieve the above technical objectives, the technical solution adopted by the ammonia production device by catalytic hydrolysis of urea of the present invention is as follows: An ammonia production device by catalytic hydrolysis of urea includes a reaction kettle. A feed inlet is provided in the middle of the reaction kettle. A heating coil is provided at the lower part of one end of the reaction kettle, and the heating coil penetrates into the inner side of the reaction kettle. Steam flows through the heating coil. A catalyst addition mechanism is provided on the outer wall of the reaction kettle. The catalyst addition mechanism includes a U-shaped medicine adding pipe and a cylinder. The bent part of the medicine adding pipe is located inside the reaction kettle. A number of perforations are provided on the outer wall of the medicine adding pipe. Both ends of the medicine adding pipe are located outside the reaction kettle. A number of medicine shells are filled in the medicine adding pipe, and catalysts are contained in the medicine shells. The cylinder is located outside the end of the chemical addition pipe, and the cylinder is used to push the medicine shell to move within the chemical addition pipe.

[0007] Preferably, a stirring shaft driven by a motor is provided inside the housing. The stirring shaft extends along the height direction of the housing. A plurality of stirring blades are provided on the outer wall of the stirring shaft, and the heating coil extends along the length direction of the housing.

[0008] Preferably, the stirring blades and the heating coil are arranged in a staggered manner in the length direction of the housing.

[0009] Preferably, a flexible part is provided at a position of the chemical addition pipe close to the inner wall of the reaction kettle. The flexible part is communicated with and integrally formed with the chemical addition pipe. An electric valve is provided on the flexible part, and the electric valve is used to contract the flexible part.

[0010] Preferably, when the flexible part is in a contracted state, the part of the chemical addition pipe located inside the reaction kettle and the part of the chemical addition pipe located outside the reaction kettle are not communicated with each other.

[0011] Preferably, the perforation is located inside the reaction kettle, and the inner diameter of the perforation is smaller than the outer diameter of the medicine shell.

[0012] Preferably, one end of the chemical addition pipe is the medicine inlet end and the other end is the medicine outlet end. The height of the medicine inlet end gradually decreases in the direction of the chemical addition pipe, and the medicine outlet end gradually increases in the direction of the chemical addition pipe; A plurality of the medicine shells include an upper shell and a lower shell. The upper shell and the lower shell are screwed together by threads, and both the upper shell and the lower shell are porous.

[0013] Preferably, the cylinder is arranged above the medicine inlet end. The push rod of the cylinder is coaxially arranged with the push rod of the flexible part. A push head is provided on the push rod of the cylinder. An inner concave surface is provided at the bottom of the push head. The outer wall of the medicine shell is attached to the inner concave surface. An outer convex surface is provided at the top of the push head. The push rod of the air rod is connected to the outer convex surface.

[0014] Preferably, a through hole is provided on the medicine inlet end. The push rod of the cylinder passes through the through hole. The inner diameter of the through hole is smaller than the outer diameter of the medicine shell.

[0015] Compared with the prior art, the beneficial effects of the present invention are: The present invention uses a cylinder to push the medicine shell, which can push the medicine shell with a new catalyst at the medicine inlet end into the inner side of the medicine adding tube, and push the medicine shell with an old catalyst at the medicine outlet end out of the outer side of the medicine adding tube, realizing the replacement of an equal amount of catalyst. Moreover, the catalyst in the medicine shell is in a solid state, improving the on-line addition of the catalyst in different usage scenarios; an outer convex surface is arranged at the top of the push head and an inner concave surface is arranged at the bottom, so that when the push head moves downward, it can reliably push the medicine shell below to move along the axial direction of the medicine adding tube, and when the push head moves upward, the outer convex surface can move the medicine shell above along the radial direction of the medicine adding tube, ensuring that the push head can reliably push. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic structural diagram of the present invention; Figure 2 is Figure 1 the enlarged structural diagram at position A in Figure 3 is the internal structural sectional view of the medicine adding tube in the present invention; Figure 4 is the state reference diagram of the opened medicine shell of the present invention.

[0017] In the figure: 1. Reactor; 11. Feed inlet; 12. Heating coil; 13. Motor; 14. Stirring shaft; 15. Stirring blade; 2. Catalyst adding mechanism; 21. Medicine adding tube; 211. Perforation; 212. Flexible part; 213. Electric valve; 214. Medicine inlet end; 2140. Through hole; 215. Medicine outlet end; 22. Cylinder; 23. Medicine shell; 231. Upper shell; 232. Lower shell; 24. Push head; 241. Inner concave surface; 242. Outer convex surface. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] The present invention will be further described below in conjunction with the drawings and specific embodiments: As Figure 1 — Figure 3 shown, a urea catalytic hydrolysis ammonia production device includes a reactor 1. A feed inlet 11 is arranged in the middle of the reactor 1. A heating coil 12 is arranged at the lower part of one end of the reactor 1. The heating coil 12 penetrates into the inner side of the reactor 1, and water vapor circulates in the heating coil 12. A catalyst adding mechanism 2 is arranged on the outer wall of the reactor 1; the catalyst adding mechanism 2 includes a U-shaped medicine adding tube 21 and a cylinder 22. The bent part of the medicine adding tube 21 is located inside the reactor 1. A plurality of perforations 211 are arranged on the outer wall of the medicine adding tube 21. Both ends of the medicine adding tube 21 are located outside the reactor 1. A plurality of medicine shells 23 are filled in the medicine adding tube 21, and a catalyst is contained in the medicine shell 23; the cylinder 22 is located outside the end of the medicine adding tube 21, and the cylinder 22 is used to push the medicine shell 23 to move in the medicine adding tube 21.

[0019] The dosing pipe 21 is filled with a number of medicine shells 23, and the medicine shells 23 are filled with catalysts. Since the dosing pipe 21 is provided with perforations 211, the catalysts can come into contact with the materials in the reaction kettle 1 and play a catalytic role. When the materials in the reaction kettle 1 are in a reaction state, the dosing pipe 21 can be closed to isolate the dosing pipe 21 from the outside world and prevent gas from leaking out through the dosing pipe 21. When it is necessary to replace the catalysts in the dosing pipe 21, a medicine shell 23 filled with new catalysts can be inserted into the dosing pipe 21. As a new medicine shell 23 is added from one end of the dosing pipe 21, an old medicine shell 23 will be extruded from the other end of the dosing pipe 21. In this way, the on-line replacement of the solid catalysts can be realized, effectively improving the A stirring shaft 14 driven by a motor 13 is arranged inside the shell. The stirring shaft 14 extends along the height direction of the shell. A number of stirring blades 15 are arranged on the outer wall of the stirring shaft 14, and the heating coil 12 extends along the length direction of the shell. Under the driving action of the motor 13, the stirring shaft 14 and the stirring blades 15 can rotate reliably, realizing the promotion of the mixing of the materials and improving the contact effect between the materials and the catalysts. Water vapor flows in the heating coil 12, realizing the heating effect on the materials and ensuring that the hydrolysis effect can be carried out reliably.

[0020] The stirring blades 15 and the heating coil 12 are arranged in a staggered manner in the length direction of the shell. In this way, there will be no collision between the stirring blades 15 and the heating coil 12, ensuring that the stirring effect and the heating effect can be carried out synchronously. Further, since the heating coil 12 is arranged at the lower part of the reaction kettle 1, the heated materials will flow upward. Under the stirring action of the stirring blades 15, the materials close to the stirring shaft 14 will rotate circumferentially. In this way, while the heating coil 12 plays a heating role, it can also play a role in promoting the flow of the materials, improving the stirring effect of the stirring blades 15 on the materials.

[0021] A flexible part 212 is arranged at the position where the dosing pipe 21 is close to the inner wall of the reaction kettle 1. The flexible part 212 is communicated with and integrally formed with the dosing pipe 21. An electric valve 213 is arranged on the flexible part 212, and the electric valve 213 is used to contract the flexible part 212. When the flexible part 212 is in a contracted state, the part of the dosing pipe 21 located inside the reaction kettle 1 is not communicated with the part of the dosing pipe 21 located outside the reaction kettle 1. That is to say, when the electric valve 213 is in a closed state, the flexible part 212 will be in a tightened state, thereby preventing the gas in the reaction kettle 1 from discharging outward through the dosing pipe 21. When it is necessary to add catalysts, the electric valve 213 and the flexible part 212 can be briefly opened, and then the catalysts can be added quickly, minimizing the loss of gas.

[0022] The perforations 211 are located inside the reaction kettle 1, and the inner diameter of the perforations 211 is smaller than the outer diameter of the medicine shell 23. In this way, it is ensured that the materials inside the reaction kettle 1 can enter the inside of the medicine adding pipe 21 through the perforations 211, and then penetrate into the inside of the medicine shell 23 to contact the catalyst, ensuring that the catalyst can reliably carry out the catalytic action. The outer diameter of the medicine shell 23 is relatively large and cannot enter the interior of the reaction kettle 1 through the perforations 211, and several medicine shells 23 can reliably move in sequence inside the medicine adding pipe 21, thereby realizing the addition of the catalyst.

[0023] One end of the medicine adding pipe 21 is the medicine inlet end 214 and the other end is the medicine outlet end 215. The height of the medicine inlet end 214 gradually decreases towards the direction of the medicine adding pipe 21, and the medicine outlet end 215 gradually increases towards the direction of the medicine adding pipe 21; several medicine shells 23 include an upper shell 231 and a lower shell 232, and the upper shell 231 and the lower shell 232 are screwed together. Both the upper shell 231 and the lower shell 232 are porous. Both the medicine inlet end 214 and the medicine outlet end 215 are inclined, ensuring that the medicine shell 23 filled with new catalyst can automatically roll into the medicine adding pipe 21, and the medicine shell 23 filled with old catalyst can automatically roll out of the medicine adding pipe 21, improving the fluency of replacement. The upper shell 231 and the lower shell 232 are detachably connected by threads, facilitating the replacement of the catalyst after opening.

[0024] The air cylinder 22 is arranged above the medicine inlet end 214. The push rod of the air cylinder 22 is coaxially arranged with the push rod of the flexible part 212. A push head 24 is arranged on the push rod of the air cylinder 22. An inner concave surface 241 is arranged at the bottom of the push head 24, and the outer wall of the medicine shell 23 fits with the inner concave surface 241. An outer convex surface 242 is arranged at the top of the push head 24, and the push rod of the air cylinder is connected to the outer convex surface 242. When the new medicine shell 23 is placed in the medicine adding pipe 21 and rolls to the vertical part of the medicine adding pipe 21, the push rod of the air cylinder 22 extends and presses this medicine shell 23 towards the bent part of the medicine adding pipe 21, thereby realizing the sequential movement of all the medicine shells 23 and ejecting the medicine shell 23 closest to the medicine outlet end 215 to complete the replacement of the medicine shell 23. The design of the inner concave surface 241 ensures that the push head 24 and the medicine shell 23 can fit tightly. When the push head 24 pushes the medicine shell 23 to move downward, if a new medicine shell 23 enters the medicine inlet end 214, it will contact the outer wall of the push rod of the air cylinder. When the push rod of the air cylinder retracts, the outer convex surface 242 on the push head 24 will push this medicine shell 23 to the outside of the push head 24, ensuring that the push head 24 can move to a high position and be ready to push the next medicine shell 23.

[0025] A through hole 2140 is arranged on the medicine inlet end 214, and the push rod of the air cylinder 22 passes through the through hole 2140. The inner diameter of the through hole 2140 is smaller than the outer diameter of the medicine shell 23. In this way, it effectively prevents the medicine shell 23 from slipping out of the medicine adding pipe 21 through the through hole 2140.

[0026] In summary, the above are only the preferred embodiments of the present invention, and are not used to limit the scope of implementation of the present invention. All equivalent changes and modifications made according to the shape, structure, features and spirit of the scope of the claims of the present invention shall be included within the scope of the claims of the present invention.

Claims

1. A urea catalytic hydrolysis ammonia production device, comprising a reactor, a feed port is provided in the middle of the reactor, a heating coil is provided at the lower part of one end of the reactor, the heating coil is penetrated to the inner side of the reactor, water vapor flows in the heating coil, and is characterized in that: A catalyst adding mechanism is provided on the outer wall of the reactor, and the catalyst adding mechanism comprises a U-shaped dosing tube and a cylinder, the bending portion of the dosing tube is located inside the reactor, a plurality of perforations are provided on the outer wall of the dosing tube, both ends of the dosing tube are located outside the reactor, the dosing tube is filled with a plurality of medicine shells, and the catalyst is contained in the medicine shells; The cylinder is located outside the end of the dosing tube, and is used to push the medicine shell to move in the dosing tube.

2. The urea catalytic hydrolysis ammonia production equipment according to claim 1, characterized in that: A stirring shaft driven by a motor is arranged in the shell, the stirring shaft extends along the height direction of the shell, a plurality of stirring blades are arranged on the outer wall of the stirring shaft, and the heating coil extends along the length direction of the shell.

3. The urea catalytic hydrolysis ammonia production equipment according to claim 2, characterized in that: The stirring blade and the heating coil are staggered in the length direction of the shell.

4. The urea catalytic hydrolysis ammonia production equipment according to claim 1, characterized in that: The dosing tube is provided with a flexible portion near the inner wall of the reactor, the flexible portion and the dosing tube are interconnected and integrally formed, and an electric valve is provided on the flexible portion, which is used to contract the flexible portion.

5. The urea catalytic hydrolysis ammonia production equipment according to claim 4, characterized in that: When the flexible portion is in a contracted state, the portion of the dosing tube located inside the reactor and the portion of the dosing tube located outside the reactor are not communicated with each other.

6. The urea catalytic hydrolysis ammonia production equipment according to claim 4, characterized in that: The through hole is located on the inner side of the reactor, and the inner diameter of the through hole is smaller than the outer diameter of the medicine shell.

7. The equipment for producing ammonia by catalytic hydrolysis of urea according to claim 6, characterized in that: One end of the dosing tube is the drug inlet end, and the other end is the drug outlet end. The height of the drug inlet end gradually decreases toward the direction of the dosing tube, and the height of the drug outlet end gradually increases toward the direction of the dosing tube. Several of the medicine shells include an upper shell and a lower shell. The upper shell and the lower shell are screwed together by threads, and both the upper shell and the lower shell are porous.

8. The equipment for producing ammonia by catalytic hydrolysis of urea according to claim 7, characterized in that: The cylinder is arranged above the medicine feeding end, the push rod of the cylinder is coaxially arranged with the push rod of the flexible part, a push head is provided on the push rod of the cylinder, an inner concave surface is provided at the bottom of the push head, the outer wall of the medicine shell is fitted with the inner concave surface, the top of the push head is provided with an outer convex surface, and the push rod of the gas rod is connected with the outer convex surface.

9. The equipment for producing ammonia by catalytic hydrolysis of urea according to claim 8, characterized in that: A through hole is provided on the medicine feeding end, and the push rod of the cylinder is inserted into the through hole, and the inner diameter of the through hole is smaller than the outer diameter of the medicine shell.

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