Rapid urea dissolving and storing system for preparing ammonia from urea

Abstract

The utility model relates to the field of environmental protection, and discloses a urea rapid dissolving and storing system for preparing ammonia from urea, which comprises a dissolving tank, a storing tank connected with the dissolving tank, a jet pump, a urea crusher and a urea weighing machine, the volume of the dissolving tank and the volume of the storage tank are both smaller than 3 m < 3 >. The lower portion of the dissolving tank is provided with a first steam input pipeline used for inputting steam into the urea tank. A stirring device is arranged on the dissolving tank; the jet pump is arranged at the lower part of the dissolving tank; the jet flow direction of the jet pump is below the first steam input pipeline; a liquid inlet source of the jet pump is liquid in the dissolving tank; a urea powder filling port is formed in the dissolving tank; and the urea crusher, the urea weighing machine and the urea powder filling port are connected in sequence. According to the system, the production efficiency of the urea solution of the small-volume reaction kettle is improved from two aspects of urea particle pulverization and solid-liquid contact homogenization, so that the system can be arranged in a limited space, and the requirement on the site area is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of environmental protection equipment, in particular to a urea rapid dissolution and storage system for producing ammonia from urea. Background Art

[0002] Ammonia denitrification is an important process for flue gas denitrification. Ammonia is produced using the urea catalytic method. Urea enters the ammonia reactor in the form of a solution.

[0003] The existing urea solution is mostly prepared by steam heating, which is easier to achieve in a large-capacity reactor, where the reactor is large and the solid-liquid contact is highly uniform.

[0004] In the denitrification system renovation projects undertaken by the applicant for some small and medium-sized power plants, the equipment layout area is severely limited. Within this limited space, it is necessary to achieve rapid dissolution of urea and improve the production efficiency of urea solution. The small volume (1 to 3 cubic meters) of the reactor itself limits the realization of the goal of rapid and efficient production of urea solution.

[0005] In order to achieve rapid intermittent urea production in small-volume reactors, improving the solid-liquid contact efficiency is a very important, or even the only, means.

[0006] Therefore, the technical problem solved in this case is: how to achieve rapid intermittent production of urea solution based on a small-volume reactor. Utility Model Content

[0007] The purpose of the utility model is to solve the above-mentioned problems and provide a urea rapid dissolution and storage system for urea production and ammonia production. The system improves the production efficiency of urea solution in a small-volume reactor from the two aspects of urea particle powderization and solid-liquid contact homogenization. The system can be arranged in a limited space, reducing the requirement for site area.

[0008] To achieve the above objectives, the present invention provides the following technical solutions:

[0009] A urea rapid dissolution and storage system for urea production from ammonia, comprising a dissolution tank, a storage tank connected to the dissolution tank, a jet pump, a urea crusher, and a urea weighing machine; the volume of the dissolution tank and the storage tank are both less than 3m 3A first steam input pipe for inputting water vapor into the urea tank is provided at the lower part of the dissolving tank; a stirring device is provided on the dissolving tank; the jet pump is provided at the lower part of the dissolving tank; the jet direction of the jet pump is below the first steam input pipe; the liquid inlet source of the jet pump is the liquid in the dissolving tank; a urea powder filling port is provided on the dissolving tank; the urea crusher, urea weighing machine, and urea powder filling port are connected in sequence.

[0010] Compared with the prior art, the beneficial effects of the present invention are:

[0011] This utility model improves the efficient production of urea solutions in small-volume reactors by pulverizing urea particles and homogenizing solid-liquid contact. More specifically, a urea grinder is used to pulverize urea particles, increasing the specific surface area of ​​the solids. The rational positioning of the stirring device, first steam inlet pipe, and jet pump, along with the jet pump's auxiliary jet flow to enhance fluid mixing, achieves good solid-liquid contact and achieves efficient intermittent urea solution production. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is a flow chart of Example 1;

[0013] Figure 2 is a top view of the first steam input pipeline of Example 1;

[0014] Figure 3 This is a bottom view of the first steam input pipe of Example 1. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0016] Example 1

[0017] refer to Figure 1 A urea rapid dissolution and storage system for urea production from ammonia, comprising a dissolution tank 1, a storage tank 2 connected to the dissolution tank 1, a jet pump 3, a urea crusher 4, and a urea weighing machine 5; the volume of the dissolution tank 1 and the storage tank 2 are both less than 3m 3A first steam input pipe 6 for inputting water vapor into the urea tank is provided at the lower part of the dissolving tank 1; a stirring device 7 is provided on the dissolving tank 1; the jet pump 3 is arranged at the lower part of the dissolving tank; the jet direction of the jet pump 3 is below the first steam input pipe; the liquid inlet source of the jet pump 3 is the liquid in the dissolving tank 1; a urea powder filling port 8 is provided on the dissolving tank 1; the urea crusher 4, the urea weighing machine 5, and the urea powder filling port 8 are connected in sequence.

[0018] The production process of the urea solution of this embodiment is as follows:

[0019] Desalted water (condensate obtained by hydrophobic treatment) is injected into the dissolution tank 1, and then steam is introduced to heat the desalted water until it is near boiling. A urea grinder 4 crushes 3-5 mm urea granules into a powder, which is then weighed by a urea weighing machine 5 and quantitatively injected into the dissolution tank 1. This injection process can be one-time or continuous. If continuous, a propulsion device such as an auger is required between the urea powder filling port 8 and the urea weighing machine 5. Urea dissolution is an endothermic process, so water vapor must be continuously supplied through the first steam inlet pipe 6 to maintain the system temperature. Simultaneously, a jet pump 3 draws solution from the solvent tank and injects it into the dissolution tank 1. By injecting the solution below the first steam inlet pipe, the fluidity of the liquid at the bottom of the tank is increased, improving the overall mixing efficiency of the liquid. During this process, the stirring device 7 operates continuously. Once all the urea powder has dissolved, the liquid is transferred to the storage tank 2 for insulation.

[0020] In this embodiment, by powdering urea particles and stirring and jetting the urea solution, the specific surface area of ​​the solid and the uniformity of solid-liquid contact can be increased, thereby achieving the goal of efficient intermittent production.

[0021] Preferably, a second steam input pipe 9 is provided at the lower portion of the storage tank 2 .

[0022] In this embodiment, the first steam input pipe 6 and the second steam input pipe 9 are both serpentine coil structures, and multiple steam discharge ports 10 are provided on the upper and lower surfaces of the first steam input pipe 6 and the second steam input pipe 9. More preferably, gaps are provided between adjacent turns of the serpentine coil to facilitate the upward or downward movement of liquid, gas, and solids through these gaps, thereby improving solid contact and stirring effects. The upper and lower arrangement of the steam discharge ports 10 can improve the uniformity of steam distribution. In particular, the multiple steam discharge ports 10 on the lower surfaces of the first steam input pipe 6 and the second steam input pipe 9 allow the steam to briefly descend and mix with the liquid in the jet pump 3, thereby improving the gas-liquid mixing effect.

[0023] In this embodiment, the volume of the dissolving tank 1 and the storage tank 2 are both 1 to 2 m 3 A pump 12 is provided between the dissolving tank 1 and the storage tank 2 .

[0024] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements or modifications can be made without departing from the principles of the present invention. These improvements or modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A urea rapid dissolution and storage system for urea production of ammonia, comprising a dissolution tank and a storage tank connected to the dissolution tank, characterized in that: It also includes a jet pump, a urea crusher, and a urea weighing machine; the volume of the dissolving tank and the storage tank are both less than 3m 3 A first steam input pipe for inputting water vapor into the urea tank is provided at the lower part of the dissolving tank; a stirring device is provided on the dissolving tank; the jet pump is provided at the lower part of the dissolving tank; the jet direction of the jet pump is below the first steam input pipe; the liquid inlet source of the jet pump is the liquid in the dissolving tank; a urea powder filling port is provided on the dissolving tank; the urea crusher, urea weighing machine, and urea powder filling port are connected in sequence.

2. The urea rapid dissolution and storage system for urea production of ammonia according to claim 1, characterized in that: A second steam input pipeline is provided at the lower portion of the storage tank.

3. The urea rapid dissolution and storage system for urea production of ammonia according to claim 1, characterized in that: The volume of the dissolving tank and storage tank is 1 to 2 m 3 .

4. The urea rapid dissolution and storage system for urea production of ammonia according to claim 1, characterized in that: The urea grinder is used to grind urea particles with a particle size of 3 to 5 mm into powdered urea.

5. The urea rapid dissolution and storage system for urea production of ammonia according to claim 1, characterized in that: A pump is provided between the dissolving tank and the storage tank.

6. The urea rapid dissolution and storage system for urea production of ammonia according to claim 2, characterized in that: The first steam input pipe and the second steam input pipe are both serpentine coil structures.

7. The urea rapid dissolution and storage system for urea production of ammonia according to claim 6, characterized in that: A plurality of steam discharge ports are provided on the upper surfaces of the first steam input pipe and the second steam input pipe.

8. The urea rapid dissolution and storage system for urea production of ammonia according to claim 7, characterized in that: The lower surfaces of the first steam input pipe and the second steam input pipe are also provided with a plurality of steam discharge ports.

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