Waste recycling device after waste gas treatment

Abstract

A waste recycling device after waste gas treatment comprises a washing tower, an alkali washing circulating tank, an arsenic removal liquid preparation barrel, a motor supporting rod, a motor, a rotating shaft, stirring blades, a rotating rod, a scraping plate, a mixer and a solid-liquid mixing grinding machine. The sulfur-containing waste gas washing liquid obtained after waste gas treatment can be conveyed into the arsenic removal liquid preparation barrel through the solid-liquid mixing pump to be mixed and blended with the arsenic removal agent, the blended arsenic removal agent is mixed with phosphoric acid through the mixer and then enters the arsenic removal system, waste liquid recycling is achieved, the use amount of the arsenic removal agent is reduced, cost is reduced, and the arsenic removal efficiency is improved. When sulfur-containing solid waste is generated in the waste gas treatment process, the generated solid-liquid mixed waste can be conveyed into the solid-liquid mixing grinding machine through the solid-liquid mixing pump to be ground and then conveyed into the arsenic removal liquid preparation barrel to be mixed and blended with the arsenic removal agent, and recycling of the solid waste is achieved as well.

Description

Technical Field

[0001] The utility model relates to the technical field of phosphoric acid production, in particular to a device for recycling waste after waste gas treatment. Background Art

[0002] With the development of the phosphoric acid industry, phosphoric acid has become more and more widely used. Phosphoric acid is an important raw material that can be used in food additives or feeds. When producing phosphoric acid, it is necessary to remove harmful elements contained in phosphoric acid, especially heavy metal components such as As and Pb that are harmful to the human body, and reduce them to a safe and harmless content. Therefore, it is necessary to perform arsenic removal treatment on industrial phosphoric acid and remove heavy metals at the same time. There are various methods for removing As and Pb, but most manufacturers use chemical methods. An arsenic removal agent is added to phosphoric acid, and precipitates of arsenic sulfide and lead sulfide are generated by reaction and separated out. The waste gas generated during the arsenic removal and aeration processes contains hydrogen sulfide. Since hydrogen sulfide is a toxic gas, the waste gas needs to be washed before being discharged. The common method is to wash the hydrogen sulfide-containing gas with an alkali solution, so that hydrogen sulfide reacts with the alkali solution to form sulfides with high solubility such as sodium sulfide and dissolve in the alkali solution to remove hydrogen sulfide in the waste gas. However, during the waste gas treatment process, there will be sulfur-containing waste liquid or solid waste after absorbing hydrogen sulfide, which causes difficulties in collection and treatment. Content of the Utility Model

[0003] The purpose of the utility model is to overcome the deficiencies of the above-mentioned prior art, and provide a device for recycling waste after waste gas treatment, which controls the concentration of the sulfur-containing waste gas washing liquid and then recycles it, adds it to the arsenic removal liquid, reduces the dosage of the arsenic removal agent, and can also remove arsenic and lead in phosphoric acid, achieving the purpose of purifying phosphoric acid.

[0004] The technical solution adopted by the present utility model is a waste recycling device after waste gas treatment, including a scrubbing tower and an alkali washing circulation tank. A pH detection head and a solid-liquid mixing pump are provided in the alkali washing circulation tank. The solid-liquid mixing pump is connected to a circulation pipe. The circulation pipe is connected to one end of a waste liquid pipe and one end of a solid-liquid mixing pipe. A first control valve is provided on the waste liquid pipe. The other end of the waste liquid pipe is connected to an arsenic removal liquid preparation barrel. A first liquid level gauge is provided in the arsenic removal liquid preparation barrel. A motor support rod is provided at the top of the arsenic removal liquid preparation barrel. The motor support rod is connected to a motor. The motor is connected to a rotating shaft. The rotating shaft is fixedly connected to a stirring blade and a rotating rod. Scraping plates are fixedly connected to both ends of the rotating rod. The bottom of the arsenic removal liquid preparation barrel is connected to one end of a liquid outlet pipe. A second control valve and a sight glass are provided on the liquid outlet pipe. The other end of the liquid outlet pipe is connected to a mixer. A second liquid level gauge is provided in the mixer. A third control valve is provided on the solid-liquid mixing pipe. The other end of the solid-liquid mixing pipe is connected to a solid-liquid mixing and grinding machine. The solid-liquid mixing and grinding machine is connected to one end of a discharge pipe. A fourth control valve is provided on the discharge pipe. The other end of the discharge pipe is connected to an arsenic removal agent feeding pipe. A fifth control valve is provided on the arsenic removal agent feeding pipe. The arsenic removal agent feeding pipe is connected to the arsenic removal liquid preparation barrel.

[0005] The solid-liquid mixing and grinding machine is located on a first support platform. The arsenic removal liquid preparation barrel is located on a second support platform. A first support column is connected between the first support platform and the second support platform. The bottom of the second support platform is connected to a second support column.

[0006] The mixer is connected to a phosphoric acid delivery pipe and an arsenic removal delivery pipe. A flow meter and a sixth control valve are provided on the phosphoric acid delivery pipe. A seventh control valve is provided on the arsenic removal delivery pipe.

[0007] The top end of the circulation pipe is connected to an alkali liquid spray pipe. The alkali liquid spray pipe is connected to a spray head. An eighth control valve is provided on the alkali liquid spray pipe.

[0008] A third liquid level gauge is provided on one side of the alkali washing circulation tank. An alkali liquid replenishing pipe is provided above the alkali washing circulation tank.

[0009] An exhaust gas inlet pipe is provided at the bottom on one side of the scrubbing tower. A tail gas discharge port is provided at the top of the scrubbing tower.

[0010] The beneficial effects of the present utility model: An arsenic removal liquid preparation barrel and a solid-liquid mixing and grinding machine are added. The sulfur-containing waste gas washing liquid after waste gas treatment can be transported to the arsenic removal liquid preparation barrel through the solid-liquid mixing pump to be mixed and prepared with the arsenic removal agent. The prepared arsenic removal agent then enters the arsenic removal system after being mixed with phosphoric acid through the mixer, achieving the recycling of waste liquid, reducing the usage amount of the arsenic removal agent, and reducing costs.

[0011] When solid waste containing sulfur is generated during the waste gas treatment process, the generated solid-liquid mixed waste can be transported by a solid-liquid mixing pump to a solid-liquid mixing grinder for grinding and then transported to an arsenic removal liquid preparation tank to be mixed with an arsenic removal agent, thus achieving the recycling of solid waste as well.

[0012] The alkali washing circulation tank is equipped with a PH detection head to detect the PH value of the alkali liquid in the alkali washing circulation tank at any time. A sight glass is installed on the liquid outlet pipe to facilitate viewing the situation of the mixed arsenic removal liquid prepared in the arsenic removal liquid preparation tank. Brief Description of the Drawings

[0013] Figure 1 is a schematic diagram of the overall structure of the present utility model.

[0014] Figure 2 is a schematic diagram of the internal structure of the arsenic removal liquid preparation tank of the present utility model.

[0015] In the figure: 1. Washing tower, 2. Alkali washing circulation tank, 3. PH detection head, 4. Solid-liquid mixing pump, 5. Circulation pipe, 6. Waste liquid pipe, 7. First control valve, 8. Arsenic removal liquid preparation tank, 9. First liquid level gauge, 10. Motor support rod, 11. Motor, 12. Rotating shaft, 13. Stirring blade, 14. Rotating rod, 15. Scraper, 16. Liquid outlet pipe, 17. Second control valve, 18. Sight glass, 19. Mixer, 20. Second liquid level gauge, 21. Solid-liquid mixing pipe, 22. Third control valve, 23. Solid-liquid mixing grinder, 24. Discharge pipe, 25. Fourth control valve, 26. Arsenic removal agent feeding pipe, 27. Fifth control valve, 28. First support platform, 29. Second support platform, 30. First support column, 31. Second support column, 32. Phosphoric acid delivery pipe, 33. Flowmeter, 34. Sixth control valve, 35. Arsenic removal delivery pipe, 36. Seventh control valve, 37. Alkali liquid spray pipe, 38. Sprayer, 39. Eighth control valve, 40. Third liquid level gauge, 41. Alkali liquid supplement pipe, 42. Waste gas inlet pipe, 43. Tail gas discharge port. Detailed Embodiment

[0016] The drawings are only for illustrative purposes and should not be construed as a limitation of this patent; for better illustration of this embodiment, some components in the drawings may be omitted, enlarged or reduced, which do not represent the dimensions of the actual product; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0017] Referring to the attached drawings, a waste recycling device after waste gas treatment includes a scrubbing tower 1 and an alkali washing circulation tank 2. A pH detector 3 and a solid-liquid mixing pump 4 are provided in the alkali washing circulation tank 2. The solid-liquid mixing pump 4 is connected to a circulation pipe 5. The circulation pipe 5 is connected to one end of a waste liquid pipe 6 and one end of a solid-liquid mixing pipe 21. A first control valve 7 is provided on the waste liquid pipe 6. The other end of the waste liquid pipe 6 is connected to an arsenic removal liquid preparation barrel 8. A first liquid level gauge 9 is provided in the arsenic removal liquid preparation barrel 8. A motor support rod 10 is provided at the top of the arsenic removal liquid preparation barrel 8. The motor support rod 10 is connected to a motor 11. The motor 11 is connected to a rotating shaft 12. The rotating shaft 12 is fixedly connected to a stirring blade 13 and a rotating rod 14. Scrapers 15 are fixedly connected to both ends of the rotating rod 14. The bottom of the arsenic removal liquid preparation barrel 8 is connected to one end of a liquid outlet pipe 16. A second control valve 17 and a sight glass 18 are provided on the liquid outlet pipe 16. The other end of the liquid outlet pipe 16 is connected to a mixer 19. A second liquid level gauge 20 is provided in the mixer 19. A third control valve 22 is provided on the solid-liquid mixing pipe 21. The other end of the solid-liquid mixing pipe 21 is connected to a solid-liquid mixing and grinding machine 23. The solid-liquid mixing and grinding machine 23 is connected to one end of a discharge pipe 24. A fourth control valve 25 is provided on the discharge pipe 24. The other end of the discharge pipe 24 is connected to an arsenic removal agent feeding pipe 26. A fifth control valve 27 is provided on the arsenic removal agent feeding pipe 26. The arsenic removal agent feeding pipe 26 is connected to the arsenic removal liquid preparation barrel 8.

[0018] The solid-liquid mixing and grinding machine 23 is located on a first support platform 28. The arsenic removal liquid preparation barrel 8 is located on a second support platform 29. A first support pillar 30 is connected between the first support platform 28 and the second support platform 29. The bottom of the second support platform 29 is connected to a second support pillar 31.

[0019] The mixer 19 is connected to a phosphoric acid delivery pipe 32 and an arsenic removal delivery pipe 35. A flow meter 33 and a sixth control valve 34 are provided on the phosphoric acid delivery pipe 32. A seventh control valve 36 is provided on the arsenic removal delivery pipe 35.

[0020] The top end of the circulation pipe 5 is connected to an alkali liquid spray pipe 37. The alkali liquid spray pipe 37 is connected to a spray head 38. An eighth control valve 39 is provided on the alkali liquid spray pipe 37.

[0021] A third liquid level gauge 40 is provided on one side of the alkali washing circulation tank 2. An alkali liquid replenishing pipe 41 is provided above the alkali washing circulation tank 2.

[0022] An exhaust gas inlet pipe 42 is provided at the bottom on one side of the scrubbing tower 1. A tail gas discharge port 43 is provided at the top of the scrubbing tower 1.

[0023] When the waste recycling device after waste gas treatment is in use, first inject alkali solution into the alkali washing circulation tank 2 from the alkali solution supplement pipe 41. Then, the waste gas after arsenic removal enters the washing tower 1 from the waste gas inlet pipe 42. Turn on the solid-liquid mixing pump 4 and the eighth control valve 39 to make the alkali solution spray out from the spray head 38 to remove hydrogen sulfide in the waste gas. The sulfur-containing waste liquid will return to the alkali washing circulation tank 2. When the pH value of the alkali solution in the alkali washing circulation tank 2 drops below 10, close the eighth control valve 39 and stop transporting the waste gas into the washing tower 1 at the same time. Start the first control valve 7 to make the alkali solution in the alkali washing circulation tank 2 enter the arsenic removal liquid preparation barrel 8. Turn on the motor 11, and the motor 11 drives the rotating shaft 12 to rotate, so that the stirring blade 13 and the scraping plate 15 rotate at the same time, and mix and prepare the arsenic removal agent and the alkali solution that enter the arsenic removal liquid preparation barrel 8 through the arsenic removal agent feeding pipe 26. After preparation, start the second control valve 17 to make the prepared arsenic removal agent enter the mixer 19, and mix with the phosphoric acid that enters the mixer 19 through the phosphoric acid delivery pipe 32. Then start the seventh control valve 36 to make the materials in the mixer 19 enter the next arsenic removal system for arsenic removal. The waste gas after arsenic removal enters the washing tower 1 from the waste gas inlet pipe 42 to complete the cycle.

[0024] When the pH value of the alkali solution in the alkali washing circulation tank 2 drops below 10 and is transported to the arsenic removal liquid preparation barrel 8, inject new alkali solution into the alkali washing circulation tank 2 from the alkali solution supplement pipe 41 to make the pH value of the alkali solution in the alkali washing circulation tank 2 ≥ 13 and continue to use. Repeatedly use like this to achieve the recycling of the waste liquid.

[0025] When solid waste is generated during the washing of the waste gas in the washing tower 1, similarly, when the pH value of the alkali solution in the alkali washing circulation tank 2 drops below 10, start the third control valve 22 to first transport the solid-liquid mixed waste to the solid-liquid mixing grinder 23 to grind the solid waste, and then enter the arsenic removal liquid preparation barrel 8 through the discharge pipe 24 and the arsenic removal agent feeding pipe 26. Then repeat the above operations to achieve the purpose of recycling.

[0026] The arsenic removal liquid preparation barrel 8 and the solid-liquid mixing grinder 23 are added, and the sulfur-containing waste gas washing liquid after waste gas treatment can be transported to the arsenic removal liquid preparation barrel 8 through the solid-liquid mixing pump 4 to be mixed and prepared with the arsenic removal agent. The prepared arsenic removal agent is then mixed with phosphoric acid through the mixer 19 and enters the arsenic removal system, achieving the recycling of the waste liquid, reducing the usage amount of the arsenic removal agent, and reducing the cost.

[0027] When solid waste containing sulfur is generated during the waste gas treatment process, the generated solid-liquid mixed waste can be transported to the solid-liquid mixing grinder 23 through the solid-liquid mixing pump 4 to be ground and then transported to the arsenic removal liquid preparation barrel 8 to be mixed and prepared with the arsenic removal agent, also achieving the recycling of the solid waste.

[0028] The caustic washing circulating tank 2 is equipped with a PH detector head 3 to detect the PH value of the caustic solution in the caustic washing circulating tank 2 at any time. A sight glass 18 is installed on the liquid outlet pipe 16 to facilitate viewing the situation of the mixed arsenic removal solution prepared by the arsenic removal solution preparation tank 8.

[0029] The above embodiments of the new type are merely examples for clearly explaining the present invention, rather than limitations on the implementation manners of the present invention. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation manners here. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A waste recycling device after waste gas treatment, comprising a washing tower (1) and an alkali washing circulation tank (2), characterized in that: The alkali washing circulation tank (2) is provided with a pH detection head (3) and a solid-liquid mixing pump (4), the solid-liquid mixing pump (4) is connected to a circulation pipe (5), the circulation pipe (5) is connected to one end of a waste liquid pipe (6) and one end of a solid-liquid mixing pipe (21), the waste liquid pipe (6) is provided with a first control valve (7), the other end of the waste liquid pipe (6) is connected to a dearsenicating liquid preparation barrel (8), the dearsenicating liquid preparation barrel (8) is provided with a first liquid level gauge (9), the top of the dearsenicating liquid preparation barrel (8) is provided with a motor support rod (10), the motor support rod (10) is connected to a motor (11), the motor (11) is connected to a rotating shaft (12), the rotating shaft (12) is fixedly connected to a stirring blade (13) and a rotating rod (14), the two ends of the rotating rod (14) are fixedly connected to a scraper (15), ... The bottom of the barrel (8) is connected to one end of a liquid outlet pipe (16), the liquid outlet pipe (16) is provided with a second control valve (17) and a sight glass (18), the other end of the liquid outlet pipe (16) is connected to a mixer (19), a second liquid level gauge (20) is provided in the mixer (19), a third control valve (22) is provided on the solid-liquid mixing pipe (21), the other end of the solid-liquid mixing pipe (21) is connected to a solid-liquid mixing grinder (23), the solid-liquid mixing grinder (23) is connected to one end of a discharge pipe (24), the discharge pipe (24) is provided with a fourth control valve (25), the other end of the discharge pipe (24) is connected to a dearsenicizing agent feeding pipe (26), the dearsenicizing agent feeding pipe (26) is provided with a fifth control valve (27), and the dearsenicizing agent feeding pipe (26) is connected to a dearsenicizing liquid preparation barrel (8).

2. The waste recycling device after exhaust gas treatment according to claim 1 is characterized in that: The solid-liquid mixing grinder (23) is located on a first support platform (28), the arsenic removal liquid preparation barrel (8) is located on a second support platform (29), a first support pillar (30) is connected between the first support platform (28) and the second support platform (29), and the bottom of the second support platform (29) is connected to a second support pillar (31).

3. The waste recycling device after exhaust gas treatment according to claim 1 is characterized in that: The mixer (19) is connected to a phosphoric acid delivery pipe (32) and an arsenic removal delivery pipe (35); a flow meter (33) and a sixth control valve (34) are provided on the phosphoric acid delivery pipe (32); and a seventh control valve (36) is provided on the arsenic removal delivery pipe (35).

4. The waste recycling device after exhaust gas treatment according to claim 1 is characterized in that: The top end of the circulation pipe (5) is connected to an alkali solution spray pipe (37), the alkali solution spray pipe (37) is connected to a spray head (38), and an eighth control valve (39) is provided on the alkali solution spray pipe (37).

5. The waste recycling device after exhaust gas treatment according to claim 1 is characterized in that: A third liquid level gauge (40) is provided on one side of the alkali washing circulation tank (2), and an alkali solution replenishing pipe (41) is provided above the alkali washing circulation tank (2).

6. The waste recycling device after exhaust gas treatment according to claim 1 is characterized in that: A waste gas inlet pipe (42) is provided at the bottom of one side of the washing tower (1), and a tail gas discharge port (43) is provided at the top of the washing tower (1).

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