Novel urea hydrolysis system capable of preventing liquid level fluctuation

Abstract

The utility model relates to the technical field of urea hydrolysis, and discloses a novel urea hydrolysis system capable of preventing liquid level fluctuation, which comprises a urea inlet valve and a hydrolyzer, one side of the urea inlet valve is connected with a urea inlet pipe, and the other side of the urea inlet valve is connected with a solution coil pipe. Inlet steam is used for dewatering to preheat feeding urea flowing in the solution coil pipe, the temperature difference of the introduced urea is reduced, uniform heating is completed under the two-layer distributed heating effect of the heating coil pipe, the action area of the heating coil pipe of the hydrolyzer is effectively increased, a urea solution can be uniformly heated, local overtemperature is prevented, and the service life of the hydrolyzer is prolonged. The phenomenon that the liquid level of a urea solution fluctuates severely due to factors such as rapid temperature change is prevented, meanwhile, drained water of the heating coil pipe is introduced into the urea preheater, the utilization value of drained water heat and water quantity of the hydrolyzer can be greatly improved, and double waste of the drained water heat and the water quantity is avoided.

Description

Technical Field

[0001] This utility model relates to the field of urea hydrolysis technology, specifically a novel urea hydrolysis system for preventing liquid level fluctuations. Background Technology

[0002] Urea, also known as urea or carbamide, is a white, odorless, tasteless crystalline solid that is readily soluble in water, ethanol, and benzene, and slightly soluble in ether and chloroform. Urea is one of the simplest organic compounds and a major nitrogenous end product of protein metabolism in mammals and certain fish. It can be used as fertilizer, animal feed, explosives, glue stabilizer, and chemical raw material. Named for its presence in human urine, urea is often processed using a hydrolysis system. When the load on a thermal power unit fluctuates significantly, and the ammonia demand increases sharply, the opening of the product gas outlet valve in the urea hydrolyzer increases. This causes a decrease in internal pressure within the hydrolyzer. Since the steam valve adjusts its opening based on pressure, it will further increase its opening, raising the hydrolyzer temperature and accelerating the product gas generation rate.

[0003] However, since the hydrolyzer mainly relies on the heating coil at the bottom for heating, the accelerated heating rate can cause uneven heating of the urea solution inside the hydrolyzer, leading to localized overheating and boiling. This results in drastic fluctuations in the hydrolyzer's liquid level, requiring frequent adjustments to the urea solution inlet valve. When the false liquid level exceeds the limit, it can also cause frequent closure of the urea solution inlet shut-off valve. This situation causes the actual liquid level inside the hydrolyzer to continuously decrease, especially when the product gas generation is large and the urea solution temperature is high, which can have a serious adverse impact on the hydrolyzer's operating conditions. Furthermore, currently used urea hydrolyzers have only one urea solution inlet, and the urea solution entering the hydrolyzer is generally only around 40°C, a significant difference from the hydrolyzer's temperature of around 140°C. When the lower-temperature urea solution encounters the higher-temperature urea solution, it will rapidly vaporize, causing a sharp increase in volume and resulting in drastic fluctuations in the hydrolyzer's liquid level or vibration of the hydrolyzer itself. Therefore, this does not meet current requirements. To address this, we propose a novel urea hydrolysis system to prevent liquid level fluctuations. Utility Model Content

[0004] The purpose of this invention is to provide a novel urea hydrolysis system that prevents liquid level fluctuations, thereby solving the problem mentioned in the background art that severe fluctuations in the liquid level of the hydrolyzer or vibrations of the hydrolyzer body can have a serious adverse effect on the operation of the hydrolyzer.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a novel urea hydrolysis system for preventing liquid level fluctuations, comprising a urea inlet valve and a hydrolyzer. One side of the urea inlet valve is connected to a urea inlet pipe, and the other side of the urea inlet valve is connected to a solution coil. A urea preheater is installed outside the solution coil. A preheating outlet valve is connected to the upper right side of the urea preheater, and an overflow pipe is connected to the right side of the preheating outlet valve. A hydrolyzer inlet valve is connected above the solution coil, and a hydrolyzer regulating valve is connected in front of the hydrolyzer inlet valve. A solution injection pipe is installed at the front end of the hydrolyzer regulating valve.

[0006] The hydrolyzer is located on the upper side outside the solution injection pipe. A heating coil is provided on the lower side inside the hydrolyzer. A steam inlet regulating valve is provided on one side above the heating coil. A steam inlet valve is connected to the other side of the steam inlet regulating valve. A condensate outlet valve is provided on one side below the heating coil.

[0007] A stirring blade is provided in the middle of the inner side of the hydrolyzer, and a solution reflux valve is connected to the bottom left side of the hydrolyzer, and a solution reflux regulating valve is connected to the front end of the solution reflux valve.

[0008] Preferably, the urea inlet pipe is connected to the solution injection pipe via the urea inlet valve, the solution coil, the hydrolyzer inlet valve, and the hydrolyzer regulating valve; the steam inlet valve is connected to the steam inlet regulating valve and the heating coil; and the heating coil is connected to the urea preheater via the drain outlet valve.

[0009] Preferably, the solution spray pipe includes a spray branch pipe and a spray hole, and the spray branch pipe has a spray hole on its surface.

[0010] Preferably, a rotating motor is installed at the upper center of the hydrolyzer, and the output end of the rotating motor is connected to a rotating screw, with an upper limit plate fixed at the upper end of the rotating screw.

[0011] Preferably, the outer surface of the rotating screw is provided with a sliding sleeve, and the bottom of the rotating screw is provided with a lower limit plate. The rotating motor is rotatably connected to the sliding sleeve and the stirring blade through the rotating screw, and the sliding sleeve is threadedly connected to the rotating screw.

[0012] Preferably, the inner surface of the sliding sleeve is provided with connecting springs on both sides, and the front end of the connecting spring is provided with a locking head. The outer side of the locking head is provided with an arc-shaped locking groove. The locking head is elastically connected to the sliding sleeve through the connecting spring, and the locking head is engaged with the rotating screw through the arc-shaped locking groove.

[0013] Compared with the prior art, the beneficial effects of this utility model are:

[0014] 1. This utility model utilizes a urea preheater to preheat the urea feed flowing through the solution coil using steam condensate, thereby reducing the temperature difference of the incoming urea. Furthermore, the two-layer dispersed heating of the heating coil ensures uniform heating, effectively increasing the effective area of ​​the hydrolyzer's heating coil and uniformly heating the urea solution. This prevents localized overheating and avoids drastic fluctuations in the urea solution level caused by rapid temperature changes. Simultaneously, the condensate from the heating coil is introduced into the urea preheater, significantly improving the utilization value of the condensate heat and water in the hydrolyzer, avoiding the double waste of condensate heat and water.

[0015] 2. In this utility model, the spray holes arranged on the spray branch pipe can make the urea solution evenly distributed inside the hydrolyzer, effectively preventing significant local temperature differences. At the same time, the rotating motor drives the rotating screw to rotate, so that the sliding sleeve and the stirring blade can stir the solution when it moves down and rotates. This helps to accelerate the mixing of the newly added solution and further avoids the phenomenon of steam and water bubbling due to uneven heating of the solution mixture. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall system of this utility model;

[0017] Figure 2 This is a schematic diagram of the overall external three-dimensional structure of this utility model;

[0018] Figure 3 This is a partial top view of the solution jetting pipe of this utility model;

[0019] Figure 4 This is a schematic diagram of the heating coil structure of this utility model;

[0020] Figure 5 This is a schematic diagram of the rotating screw structure of this utility model;

[0021] Figure 6 This is a schematic diagram of the internal cross-sectional structure of the sliding sleeve of this utility model;

[0022] Figure 7 For the present utility model Figure 6 Enlarged structural diagram at point A in the middle.

[0023] In the diagram: 1. Urea inlet valve; 2. Urea inlet pipe; 3. Solution coil; 4. Urea preheater; 5. Preheating outlet valve; 6. Hydrolyzer inlet valve; 7. Hydrolyzer regulating valve; 8. Solution injection pipe; 801. Injection branch pipe; 802. Injection hole; 9. Heating coil; 10. Stirring blade; 11. Solution reflux valve; 12. Solution reflux regulating valve; 13. Steam inlet valve; 14. Steam inlet regulating valve; 15. Drain outlet valve; 16. Hydrolyzer; 17. Overflow pipe; 18. Rotating motor; 19. Rotating screw; 20. Upper limit plate; 21. Sliding sleeve; 22. Lower limit plate; 23. Connecting spring; 24. Clamping head; 25. Arc-shaped groove. Detailed Implementation

[0024] 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.

[0025] Example 1: As Figures 1-4 As shown, a novel urea hydrolysis system for preventing liquid level fluctuations includes a urea inlet valve 1 and a hydrolyzer 16 disposed above the urea inlet valve 1. A urea inlet pipe 2 is connected to one side of the urea inlet valve 1, and a spiral solution coil 3 is connected to the other side of the urea inlet valve 1. A urea preheater 4 is wrapped around the outside of the solution coil 3. A preheating outlet valve 5 is connected to the upper right side of the urea preheater 4, and an overflow pipe 17 is connected to the right side of the preheating outlet valve 5. A hydrolyzer inlet valve 6 is connected above the solution coil 3, and a hydrolyzer regulating valve 7 is connected in front of the hydrolyzer inlet valve 6. A solution injection pipe 8 disposed at the bottom of the hydrolyzer 16 is connected to the front end of the hydrolyzer regulating valve 7.

[0026] The hydrolyzer 16 is located on the upper side of the solution injection pipe 8. The lower side of the interior of the hydrolyzer 16 is provided with a double-layered heating coil 9. A steam inlet regulating valve 14 is provided on the upper side of the heating coil 9, and a steam inlet valve 13 is connected to the other side of the steam inlet regulating valve 14. A condensate outlet valve 15 is connected to the lower side of the heating coil 9. The condensate in the heating coil 9 of the hydrolyzer 16 does not directly enter the condensate tank or condensate expansion tank, but enters the urea preheater 4 at the urea inlet pipe 2. The urea solution is preheated in the urea preheater 4. At this time, the temperature of the urea solution can be increased from 40℃-42℃ to 90℃-95℃.

[0027] A stirring blade 10 is installed in the middle of the inner side of the hydrolyzer 16. A solution reflux valve 11 is connected to the bottom left side of the hydrolyzer 16, and a solution reflux regulating valve 12 is connected to the front end of the solution reflux valve 11. The urea inlet pipe 2 is connected to the solution injection pipe 8 through the urea inlet valve 1, the solution coil 3, the hydrolyzer inlet valve 6, and the hydrolyzer regulating valve 7. The steam inlet valve 13 is connected to the steam inlet regulating valve 14 and the heating coil 9, and the heating coil 9 is connected to the urea preheater 4 through the condensate outlet valve 15. Through the drain outlet valve 15, the steam cooled by the heating coil 9 can be introduced into the urea preheater 4. The heating coil 9 is arranged in a wave-like pattern in two layers, which can not only increase the heating area but also avoid uneven heating. Through the urea preheater 4, the steam can be drained to preheat the feed urea flowing through the solution coil 3, thereby reducing the temperature difference of the urea and preventing drastic fluctuations in the urea solution level caused by rapid temperature changes.

[0028] In this embodiment: Steam from the cold section of the unit enters the heating coil 9 through the steam inlet valve 13 and the steam inlet regulating valve 14 to heat the urea solution in the hydrolyzer 16. After heating, the cooled steam forms condensate and enters the urea preheater 4 through the condensate outlet valve 15. At this time, the condensate temperature is close to the boiling point. Excess condensate goes to the next stage condensate system through the overflow pipe 17 and the preheating outlet valve 5.

[0029] Meanwhile, the urea solution enters the urea preheater 4 through the urea inlet pipe 2 and urea inlet valve 1. Under the action of the solution coil 3, the heating area inside the preheater is increased, achieving a better preheating effect. The preheated urea solution then passes sequentially through the hydrolyzer inlet valve 6 and the hydrolyzer regulating valve 7. Under the action of the solution injection pipe 8, it is evenly sprayed into the hydrolyzer 16, and uniformly heated by the two layers of dispersed heating in the heating coil 9. When the unit's ammonia demand increases significantly and the liquid level fluctuates violently due to factors such as pressure and temperature, the agitator of the manual stirring blades 10 is activated to resolve the steam-water embrittlement phenomenon caused by localized overheating.

[0030] Example 2: Figures 1-7 As shown, the solution jet pipe 8 includes a jet branch pipe 801 connected to the surface of the solution jet pipe 8, and a jet hole 802 is provided on the surface of the jet branch pipe 801.

[0031] The solution spray pipe 8 is divided into eight spray branch pipes 801 by a horizontal main pipe. Each spray branch pipe 801 has ten spray holes 802 arranged on it, which can make the urea solution evenly distributed inside the hydrolyzer 16.

[0032] A rotating motor 18 is installed at the upper center of the hydrolyzer 16, and a rotating screw 19 is connected to the output end of the rotating motor 18. An upper limit plate 20 is fixed at the upper end of the rotating screw 19, a sliding sleeve 21 is provided on the outer surface of the rotating screw 19, and a lower limit plate 22 is provided at the bottom of the rotating screw 19. The rotating motor 18 is rotatably connected to the sliding sleeve 21 and the stirring blade 10 through the rotating screw 19, and the sliding sleeve 21 is threadedly connected to the rotating screw 19.

[0033] Connecting springs 23 are provided on both sides of the inner surface of the sliding sleeve 21, and a locking head 24 is installed at the front end of the connecting spring 23. An arc-shaped groove 25 is provided on the outer side of the locking head 24. The locking head 24 is elastically connected to the sliding sleeve 21 through the connecting spring 23, and the locking head 24 is engaged with the rotating screw 19 through the arc-shaped groove 25. The mixing effect of the introduced solution can be improved by rotating the stirring blade 10.

[0034] In this embodiment: By rotating the motor 18, the rotating screw 19 can be driven to rotate. Under the action of the threaded force, the sliding sleeve 21 tends to move downward on the rotating screw 19. At this time, the sliding sleeve 21, which is engaged in the arc-shaped groove 25 opened above the rotating screw 19 by the connecting spring 23 and the engaging head 24, will be pushed downward, causing the engaging head 24 to separate from the arc-shaped groove 25. This allows the sliding sleeve 21 to drive the stirring blade 10 fixedly connected to it to move downward. When the sliding sleeve 21 and the stirring blade 10 move downward to the lower limit plate 22, they will stop moving downward and only rotate with the rotating screw 19. This allows the solution to be stirred during the downward movement and final rotation, which helps to accelerate the mixing of the newly added solution and further avoids the phenomenon of steam and water bubbling due to uneven heating of the solution mixture.

[0035] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

[0036] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A novel urea hydrolysis system for preventing liquid level fluctuations, comprising a urea inlet valve (1) and a hydrolyzer (16), characterized in that: A urea inlet pipe (2) is connected to one side of the urea inlet valve (1), and a solution coil (3) is connected to the other side of the urea inlet valve (1). A urea preheater (4) is provided outside the solution coil (3). A preheating outlet valve (5) is connected to the upper right side of the urea preheater (4), and an overflow pipe (17) is connected to the right side of the preheating outlet valve (5). A hydrolyzer inlet valve (6) is connected above the solution coil (3), and a hydrolyzer regulating valve (7) is connected in front of the hydrolyzer inlet valve (6). A solution injection pipe (8) is provided at the front end of the hydrolyzer regulating valve (7). The hydrolyzer (16) is located on the upper side outside the solution injection pipe (8). A heating coil (9) is provided on the lower side inside the hydrolyzer (16). A steam inlet regulating valve (14) is provided on one side above the heating coil (9). A steam inlet valve (13) is connected to the other side of the steam inlet regulating valve (14). A condensate outlet valve (15) is provided on one side below the heating coil (9). The hydrolyzer (16) has a stirring blade (10) in the middle of its inner side, and a solution reflux valve (11) is connected to the bottom left side of the hydrolyzer (16), and a solution reflux regulating valve (12) is connected to the front end of the solution reflux valve (11).

2. The novel urea hydrolysis system for preventing liquid level fluctuations according to claim 1, characterized in that: The urea inlet pipe (2) is connected to the solution injection pipe (8) through the urea inlet valve (1), the solution coil (3), the hydrolyzer inlet valve (6) and the hydrolyzer regulating valve (7). The steam inlet valve (13) is connected to the steam inlet regulating valve (14) and the heating coil (9). The heating coil (9) is connected to the urea preheater (4) through the condensate outlet valve (15).

3. The novel urea hydrolysis system for preventing liquid level fluctuations according to claim 1, characterized in that: The solution spray pipe (8) includes a spray branch pipe (801) and a spray hole (802), and the surface of the spray branch pipe (801) is provided with a spray hole (802).

4. A novel urea hydrolysis system for preventing liquid level fluctuations according to claim 1, characterized in that: A rotating motor (18) is installed at the upper center of the hydrolyzer (16), and a rotating screw (19) is connected to the output end of the rotating motor (18). An upper limit plate (20) is fixed at the upper end of the rotating screw (19).

5. A novel urea hydrolysis system for preventing liquid level fluctuations according to claim 4, characterized in that: The outer surface of the rotating screw (19) is provided with a sliding sleeve (21), and the bottom of the rotating screw (19) is provided with a lower limit plate (22). The rotating motor (18) is rotatably connected to the sliding sleeve (21) and the stirring blade (10) through the rotating screw (19), and the sliding sleeve (21) is threadedly connected to the rotating screw (19).

6. A novel urea hydrolysis system for preventing liquid level fluctuations according to claim 5, characterized in that: The inner surface of the sliding sleeve (21) is provided with connecting springs (23) on both sides, and the front end of the connecting springs (23) is provided with a locking head (24). The outer side of the locking head (24) is provided with an arc-shaped locking groove (25). The locking head (24) is elastically connected to the sliding sleeve (21) through the connecting springs (23), and the locking head (24) is engaged with the rotating screw (19) through the arc-shaped locking groove (25).

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