Device for recovering fluorine resource in wet-process phosphoric acid
By designing a device including sodium carbonate, defluorination reaction tank, filter press and acid-removal reaction tank, the problem of waste and blockage of fluorine resources in the wet phosphoric acid system is solved, and more than 75% fluorine recovery and cleaning are achieved The blockage period is extended.
Patent Information
- Application Number
- CN202421071978.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-16
- Publication Date
- 2025-01-03
- Estimated Expiration
- 2034-05-16
AI Technical Summary
The problems of waste of fluorine resources and blockage of tanks and pipelines in wet phosphoric acid systems have led to a shortening of the clearing cycle and waste of resources.
设计了一种回收湿法磷酸中氟资源的装置，通过碳酸钠与脱氟反应槽、压滤机、酸解反应槽和浓硫酸槽的组合使用，实现氟的回收和洗涤，包括碳酸钠加料皮带与脱氟反应槽连接，磷酸管道与脱氟反应槽连接，脱氟反应槽出料输送至压滤机，滤饼洗涤后输送至渣浆槽，再输送至酸解反应槽，并利用浓硫酸和蒸汽进行反应，尾气经过洗涤后排放。
The fluorine recovery rate has reached more than 75%, reducing the blockage of the tank body and pipelines, extending the clearing cycle, and effectively utilizing fluorine resources.
Smart Images
Figure CN222287273U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of wet-process phosphoric acid production, and in particular relates to a device for recovering fluorine resources in wet-process phosphoric acid. Background Art
[0002] my country has 15 billion tons of phosphate rock reserves (based on the standard ore containing 30% P20). Currently, the annual amount of phosphate rock mined is more than 40 million tons, and it is growing at a rate of 5%. Phosphate rock contains about 3% of fluorine. After this part of fluorine resources enters the wet phosphoric acid system, because the potassium and sodium ions in the system are solidified, about 45% of the fluorine is discharged from the system along with the phosphogypsum, and about 30% of the fluorine is dissolved in the dilute phosphoric acid, which accelerates the blockage of the tank and pipeline in the wet phosphoric acid system, shortens the clearing cycle of the wet phosphoric acid system, and causes a waste of fluorine resources. Summary of the invention
[0003] Aiming at the problem that the solidification of fluorine in the above-mentioned phosphoric acid will cause blockage of the tank body and the pipeline and cause waste of fluorine resources, the utility model provides a device for recovering fluorine resources in wet-process phosphoric acid, and the technical scheme thereof is as follows: comprising a sodium carbonate feeding belt connected to the feed port of a defluorination reaction tank through a pipeline, a phosphoric acid pipeline connected to the feed port of the defluorination reaction tank through a pipeline, a discharge port of the defluorination reaction tank connected to the feed port of a filter press through a first transport pump, a filter solid outlet of the filter press connected to the feed port of a slurry tank through a pipeline, a discharge port of the slurry tank connected to the feed port of an acidolysis reaction tank through a second transport pump, an exhaust port of the acidolysis reaction tank connected to an exhaust fan through a pipeline, and the exhaust fan is connected to the next process; a concentrated sulfuric acid tank is connected to the feed port of the acidolysis reaction tank through a pipeline.
[0004] As a preferred solution, the exhaust port of the defluorination reaction tank is connected to a tail gas washing fan through a pipeline, and the tail gas washing fan is connected to a tail gas washing process.
[0005] As a preferred embodiment, the filtrate outlet of the filter press is connected to the defluorinated phosphoric acid tank through a pipeline.
[0006] As a preferred solution, the filter press is also provided with a flushing pipe.
[0007] As a preferred embodiment, a steam pipe is provided on the top of the acidolysis reaction tank, and a steam outlet of the steam pipe is located in the middle and lower part of the acidolysis reaction tank.
[0008] As a preferred solution, an overflow pipe is provided in the middle and upper part of the acidolysis reaction tank, the overflow pipe is connected in series with the third transport pump through a pipeline, and the third transport pump is connected to the next process.
[0009] As a preferred solution, a discharge pipe is provided in the middle and lower part of the acidolysis reaction tank, and the discharge pipe is arranged in parallel with the overflow pipe and in series with the third transport pump.
[0010] As a preferred embodiment, an overflow plate is arranged inside the acidolysis reaction tank to divide the internal space of the acidolysis reaction tank into a first reaction zone and a second reaction zone.
[0011] As a preferred embodiment, the steam pipelines are respectively introduced into the middle and lower parts of the first reaction zone and the second reaction zone.
[0012] As a preferred embodiment, the amount of sodium carbonate added is 3%-5% in excess of the fluorine content in the wet-process phosphoric acid, and the amount of concentrated sulfuric acid added is 5%-10% in excess of the fluorine content in the fluorine-containing slurry.
[0013] As a preferred solution, the water content of the filter cake filtered out by the filter press is controlled to be 20%-40%.
[0014] Beneficial effects of the utility model: the fluorine recovery rate of the device can reach more than 75%, which is beneficial to the operation of the wet phosphoric acid system, reduces the blockage of the tank and pipeline in the wet phosphoric acid system due to fluorine solidification, and prolongs the clearing cycle. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 It is a schematic diagram of the overall structure of the utility model.
[0016] In the figure: 1. sodium carbonate feeding belt; 2. phosphoric acid pipeline; 3. defluorination reaction tank; 31. first transport pump; 32. tail washing fan; 4. filter press; 41. flushing pipe; 5. slurry tank; 51. second transport pump; 6. defluorination phosphoric acid tank; 7. acidolysis reaction tank; 71. third transport pump; 72. tail gas fan; 73. overflow plate; 74. overflow pipeline; 75. discharge pipeline; 76. reaction zone 1; 77. reaction zone 2; 8. concentrated sulfuric acid tank; 9. steam pipeline. DETAILED DESCRIPTION
[0017] The utility model is further described in detail below based on the accompanying drawings and specific embodiments.
[0018] Example 1
[0019] A device for recovering fluorine resources in wet-process phosphoric acid comprises a sodium carbonate feeding belt 1 connected to a feed port of a defluorination reaction tank 3 through a pipeline, a phosphoric acid pipeline 2 connected to the feed port of the defluorination reaction tank 3 through a pipeline, a discharge port of the defluorination reaction tank 3 connected to the feed port of a filter press 4 through a first transport pump 31, a filtered solid outlet of the filter press 4 connected to the feed port of a slurry tank 5 through a pipeline, a discharge port of the slurry tank 5 connected to the feed port of an acidolysis reaction tank 7 through a second transport pump 51, an exhaust port of the acidolysis reaction tank 7 connected to an exhaust fan 72 through a pipeline, and the exhaust fan 72 is connected to the next process; a concentrated sulfuric acid tank 8 is connected to the feed port of the acidolysis reaction tank 7 through a pipeline.
[0020] The exhaust port of the defluorination reaction tank 3 is connected to the tail gas washing fan 32 through a pipeline, and the tail gas washing fan 32 is connected to the tail gas washing process.
[0021] The filtrate outlet of the filter press 4 is connected to the defluorinated phosphoric acid tank 6 through a pipeline.
[0022] The filter press 4 is also provided with a flushing pipe 41 .
[0023] A steam pipe 9 is provided on the top of the acidolysis reaction tank 7 , and a steam outlet of the steam pipe 9 is located in the middle and lower part of the acidolysis reaction tank 7 .
[0024] An overflow pipe 74 is provided in the middle and upper part of the acidolysis reaction tank 7. The overflow pipe 74 is connected in series with the third transport pump 71 through a pipeline, and the third transport pump 71 is connected to the next process.
[0025] A discharge pipe 75 is provided at the middle and lower part of the acidolysis reaction tank 7 . The discharge pipe 75 is arranged in parallel with the overflow pipe 74 and in series with the third transport pump 71 .
[0026] An overflow plate 73 is arranged inside the acidolysis reaction tank 7 to divide the internal space of the acidolysis reaction tank 7 into a first reaction zone 76 and a second reaction zone 77 .
[0027] The steam pipe 9 leads to the middle and lower parts of the first reaction zone 76 and the second reaction zone 77 respectively.
[0028] Furthermore, the amount of sodium carbonate added is 3%-5% in excess of the fluorine content in the wet-process phosphoric acid, and the amount of concentrated sulfuric acid added is 5%-10% in excess of the fluorine content in the fluorine-containing slurry.
[0029] Furthermore, the water content of the filter cake filtered out by the filter press 4 is controlled to be 20%-40%.
[0030] The operation process of the above device is as follows: sodium carbonate powder is added to the defluorination reaction tank 3 through the sodium carbonate feeding belt 1, and phosphoric acid is added to the defluorination reaction tank 3 through the phosphoric acid pipeline 2. The tail gas generated by the reaction is extracted by the tail washing fan 32, and is discharged after the tail gas washing. The slurry after the reaction is transported to the filter press 4 through the first transport pump 31, and the filtrate after the filter pressure overflows to the defluorination phosphoric acid tank 6. The filter cake is washed by the flushing pipe 41 and then discharged to the slurry tank 5. The slurry in the slurry tank 5 is slurried through the flushing pipe 41 and then transported to the acid hydrolysis reaction tank 7 through the second transport pump 51. Concentrated sulfuric acid in the concentrated sulfuric acid tank 8 is added to the acidolysis reaction tank 7, and then a certain amount of low-pressure steam is introduced through the steam pipe 9. The hydrogen fluoride gas generated by the reaction is pumped to the washing, refining and absorption sections through the tail gas blower 72 to produce anhydrous hydrogen fluoride, and the remaining slurry is transported to the phosphoric acid extraction tank of the phosphoric acid workshop through the overflow pipe 74 and the third transport pump 71; an overflow plate 73 is arranged in the acidolysis reaction tank 7 to divide the reaction zone 1 76 and the reaction zone 2 77, so as to prolong the reaction time and make it fully react; a discharge pipe 75 is arranged for parking or cleaning, and emptying the acidolysis reaction tank 7.
Claims
1. A device for recovering fluorine resources from wet-process phosphoric acid, characterized in that: The method comprises: a sodium carbonate feeding belt (1) is connected to a feed port of a defluorination reaction tank (3) through a pipeline; a phosphoric acid pipeline (2) is connected to the feed port of the defluorination reaction tank (3) through a pipeline; a discharge port of the defluorination reaction tank (3) is connected to a feed port of a filter press (4) through a first transport pump (31); a filtered solid outlet of the filter press (4) is connected to a feed port of a slurry tank (5) through a pipeline; the discharge port of the slurry tank (5) is connected to a feed port of an acidolysis reaction tank (7) through a second transport pump (51); an exhaust port of the acidolysis reaction tank (7) is connected to an exhaust gas fan (72) through a pipeline; and the exhaust gas fan (72) is connected to a next process; and a concentrated sulfuric acid tank (8) is connected to the feed port of the acidolysis reaction tank (7) through a pipeline.
2. The device for recovering fluorine resources in wet-process phosphoric acid according to claim 1, characterized in that: The exhaust port of the defluorination reaction tank (3) is connected to a tail gas washing fan (32) via a pipeline, and the tail gas washing fan (32) is connected to a tail gas washing process.
3. The device for recovering fluorine resources in wet-process phosphoric acid according to claim 1, characterized in that: The filtrate outlet of the filter press (4) is connected to the defluorinated phosphoric acid tank (6) via a pipeline.
4. The device for recovering fluorine resources in wet-process phosphoric acid according to claim 1, characterized in that: The filter press (4) is also provided with a flushing pipe (41).
5. The device for recovering fluorine resources in wet-process phosphoric acid according to claim 1, characterized in that: A steam pipe (9) is provided at the top of the acidolysis reaction tank (7), and a steam outlet of the steam pipe (9) is located at the middle and lower part of the acidolysis reaction tank (7).
6. The device for recovering fluorine resources in wet-process phosphoric acid according to claim 1, characterized in that: An overflow pipe (74) is provided in the middle and upper part of the acidolysis reaction tank (7); the overflow pipe (74) and the third transport pump (71) are connected in series via a pipe; and the third transport pump (71) is connected to the next process.
7. The device for recovering fluorine resources in wet-process phosphoric acid according to claim 1, characterized in that: A discharge pipe (75) is provided at the middle and lower part of the acidolysis reaction tank (7). The discharge pipe (75) is arranged in parallel with the overflow pipe (74) and is arranged in series with the third transport pump (71).
8. The device for recovering fluorine resources in wet-process phosphoric acid according to claim 5, characterized in that: An overflow plate (73) is arranged inside the acidolysis reaction tank (7) to divide the internal space of the acidolysis reaction tank (7) into a first reaction zone (76) and a second reaction zone (77).
9. The device for recovering fluorine resources in wet-process phosphoric acid according to claim 8, characterized in that: The steam pipe (9) is connected to the middle and lower parts of the first reaction zone (76) and the second reaction zone (77) respectively.