Efficient regeneration device for tributyl phosphate extraction agent

Abstract

The utility model discloses an efficient regeneration device for a tributyl phosphate extracting agent, which comprises an alkali liquor preparation tank, a regeneration alkali washing tank, a regeneration carbon washing tank, a regeneration filter press, a regeneration phase splitting tank and a regeneration water washing tower which are sequentially connected through pipelines, and stirring mechanisms are arranged in the alkali liquor preparation tank, the regeneration alkali washing tank and the regeneration carbon washing tank. The regeneration alkaline washing tank is connected with a tributyl phosphate inlet pipe, the top of the regeneration phase splitting tank is connected with the bottom of the regeneration water washing tower, the top of the regeneration water washing tower is connected with a desalted water inlet pipe, and the top and the bottom of the regeneration water washing tower are respectively connected with an extraction agent outlet pipe and a dilute waste alkali liquid outlet pipe. The effect of improving the regeneration efficiency and the regeneration quality of the tributyl phosphate extraction agent is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of regeneration devices, in particular to a high-efficiency regeneration device for a tributyl phosphate extractant. Background Art

[0002] Wet-process phosphoric acid purification technology plays an important role in phosphorus chemical production. At present, solvent extraction is one of the main methods for phosphoric acid purification, and its efficiency and effect depend to a large extent on the selected extractant. Among the many extractants, tributyl phosphate, as a typical phosphorus-neutral extractant, is widely used in the purification process of wet-process phosphoric acid because of its strong extraction ability for phosphoric acid.

[0003] However, the large amount of impurities contained in wet-process phosphoric acid, especially organic impurities from phosphate rock, poses a serious challenge to the regeneration of tributyl phosphate extractant. During the extraction process, in addition to phosphoric acid, other organic impurities combine with tributyl phosphate to form a stable complex that is difficult to remove from the extractant by traditional desalted water regeneration methods. This leads to the gradual enrichment of organic impurities in the extractant, thereby increasing the viscosity and specific gravity of the extractant. The increase in the viscosity of the extractant not only reduces the extraction phase separation rate, but also seriously affects the quality of the refined phosphoric acid product.

[0004] In order to solve the above problems, a variety of regeneration methods for tributyl phosphate extractants have been developed, including activated carbon adsorption, vacuum distillation and alkali solution regeneration. Among them, the alkali solution regeneration method has been widely used in industrial production due to its simple operation and low cost. The alkali solution regeneration method usually uses sodium hydroxide solution to regenerate the tributyl phosphate extractant. Since tributyl phosphate is very easy to decompose in a strong alkaline environment, the alkali solution used for regeneration often uses a low-concentration sodium hydroxide solution of 5% to 10%. Although patent 201921752631.3 "A regeneration device for tributyl phosphate" improves the regeneration effect by mixing the extractant with the alkali solution and separating it with a centrifuge, there are still some problems. For example, due to its complex structure, the disc centrifuge may not be completely separated when treating the two liquid phases of tributyl phosphate and alkali solution. As a result, the waste alkali solution still contains a large amount of tributyl phosphate, which affects the regeneration recovery rate. In addition, solid suspended matter may be generated in the mixed solution of alkali solution and extractant. If these solid suspended matter are not filtered out, they will interfere with the phase separation effect during the centrifugal phase separation process and reduce the phase separation quality.

[0005] In view of this, there is an urgent need to improve and optimize the regeneration process of tributyl phosphate extractant, aiming to solve the problem of excessive tributyl phosphate entrained in the waste alkali solution due to incomplete phase separation, thereby improving the regeneration recovery rate of tributyl phosphate and ensuring the quality of refined phosphoric acid products. Summary of the invention

[0006] The technical problem to be solved by the utility model is that excessive tributyl phosphate is entrained in the waste alkali solution due to incomplete phase separation.

[0007] In order to solve the above technical problems, the technical solution adopted by the utility model is: a high-efficiency regeneration device for tributyl phosphate extractant, comprising an alkali solution preparation tank, a regeneration alkali washing tank, a regeneration carbon washing tank, a regeneration filter press, a regeneration phase separation tank and a regeneration water washing tower which are connected in sequence through pipelines, wherein the alkali solution preparation tank, the regeneration alkali washing tank and the regeneration carbon washing tank are all provided with stirring mechanisms, the regeneration alkali washing tank is connected to a tributyl phosphate inlet pipe, the top of the regeneration phase separation tank is connected to the bottom of the regeneration water washing tower, the top of the regeneration water washing tower is connected to a desalted water inlet pipe, and the top and bottom of the regeneration water washing tower are also respectively connected to an extractant outlet pipe and a dilute waste alkali solution outlet pipe.

[0008] Preferably, a heating structure and a temperature control structure are provided in the alkali solution preparation tank, and the temperature of the sodium carbonate aqueous solution prepared in the alkali solution preparation tank is 50-65°C.

[0009] Preferably, the concentration of the sodium carbonate aqueous solution is 25-35%.

[0010] Preferably, an activated carbon weight loss scale is connected to the top of the regenerated carbon washing tank.

[0011] Preferably, the connecting pipe between the regeneration alkali washing tank and the regeneration carbon washing tank is arranged obliquely, and the top of the pipe is connected to the regeneration alkali washing tank, and the two ends of the pipe are respectively connected to the top of the regeneration alkali washing tank and the regeneration carbon washing tank.

[0012] 1. The utility model provides a high-efficiency regeneration device for tributyl phosphate extractant, which continuously performs alkali washing, carbon washing and water washing on the alkali solution and tributyl phosphate extractant fed in by connecting a regeneration alkali washing tank, a regeneration carbon washing tank, a regeneration filter press, a regeneration phase separation tank and a regeneration water washing tower in series, can effectively remove the solid suspended matter in the mixed solution, and separate the fixed suspended matter attached to the activated carbon, and continuously process, thereby realizing the regeneration efficiency and regeneration effect of the tributyl phosphate extractant.

[0013] 2. The sodium carbonate solution of suitable temperature is prepared by heating and stirring in the alkali solution preparation tank. The weak alkalinity of sodium carbonate is also utilized to replace the low-concentration sodium hydroxide solution with a high-concentration sodium carbonate solution, thereby increasing the ion concentration in the aqueous phase and promoting the separation of the organic phase and the aqueous phase. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The utility model is further described below in conjunction with the accompanying drawings and embodiments:

[0015] Figure 1 It is a schematic structural diagram of an embodiment of the utility model.

[0016] In the figure: 1. alkali solution preparation tank; 2. regeneration alkali washing tank; 3. regeneration carbon washing tank; 4. regeneration filter press; 5. regeneration phase separation tank; 6. regeneration water washing tower; 7. tributyl phosphate inlet pipe; 8. carbon residue outlet pipe; 9. activated carbon weight loss scale; 10. desalted water inlet pipe; 11. extractant outlet pipe; 12. waste alkali solution outlet pipe; 13. dilute waste alkali solution outlet pipe. DETAILED DESCRIPTION

[0017] like Figure 1 The utility model provides a high-efficiency regeneration device for tributyl phosphate extractant, comprising an alkali solution preparation tank 1, a regeneration alkali washing tank 2, a regeneration carbon washing tank 3, a regeneration filter press 4, a regeneration phase separation tank 5 and a regeneration water washing tower 6 which are sequentially connected through pipelines, wherein the alkali solution preparation tank 1, the regeneration alkali washing tank 2 and the regeneration carbon washing tank 3 are all provided with stirring mechanisms, the regeneration alkali washing tank 2 is connected to a tributyl phosphate inlet pipe 7, the top of the regeneration phase separation tank 5 is connected to the bottom of the regeneration water washing tower 6, the top of the regeneration water washing tower 6 is connected to a desalted water inlet pipe 10, and the top and bottom of the regeneration water washing tower 6 are also respectively connected to an extractant outlet pipe 11 and a dilute waste alkali solution outlet pipe 13.

[0018] A 25-35% sodium carbonate aqueous solution is prepared in the alkali solution preparation tank 1, and the temperature is maintained at 50-65°C. The tributyl phosphate extractant is transported to the regeneration alkali washing tank 2 through the tributyl phosphate inlet pipe 7, and the sodium carbonate aqueous solution in the alkali solution preparation tank 1 is transported to the regeneration alkali washing tank at the same time, so that the tributyl phosphate extractant and the hot alkali solution are fully mixed in the regeneration alkali washing tank 2. After the stirring and mixing, the mixed solution formed flows through the pipeline to the regeneration carbon washing tank 3, and is fully mixed with the activated carbon in the regeneration carbon washing tank 3, and enters the regeneration filter press 4 for filtration. The filter residue passes through the regeneration filter press 4. The carbon residue outlet pipe 8 at the bottom of the raw filter press 4 is discharged, and the filtrate enters the regeneration phase separation tank 5 to stand for phase separation. The alkali solution at the lower layer is discharged through the waste alkali solution outlet pipe 12 at the bottom of the regeneration phase separation tank 5. The upper organic phase is pumped into the bottom of the regeneration water washing tower 6. The organic phase is washed in the regeneration water washing tower 6 in the reverse current through the desalted water output from the desalted water inlet pipe 10 at the top of the regeneration water washing tower 6 to obtain the purified tributyl phosphate extractant, and the regeneration of the tributyl phosphate extractant is achieved. Finally, the purified tributyl phosphate extractant is discharged through the extractant outlet pipe 11 at the top of the regeneration water washing tower 6 and returned to the extraction device. The height of the extractant outlet pipe 11 is lower than the desalted water inlet pipe 10. The diluted waste alkali solution after washing is discharged from the diluted waste alkali solution outlet pipe 13 at the bottom of the regeneration water washing tower 6.

[0019] As a preferred embodiment of the utility model, the alkali solution preparation tank 1 is provided with a heating structure and a temperature control structure, and the temperature of the sodium carbonate aqueous solution prepared in the alkali solution preparation tank 1 is 50-65°C. The sodium carbonate aqueous solution is prepared by the heating structure, the temperature control structure and the stirring mechanism to ensure that the sodium carbonate aqueous solution can be fully mixed with the tributyl phosphate extractant and react efficiently after being transported to the regeneration alkali washing tank 2.

[0020] By increasing the concentration of the sodium carbonate solution, the ion concentration in the aqueous phase of the mixed solution is increased, and the separation of the organic phase and the aqueous phase is promoted; and the alkalinity of the sodium carbonate solution is lower than that of the sodium hydroxide solution, which can prevent the decomposition of tributyl phosphate in a strong alkaline environment.

[0021] As a preferred embodiment of the present invention, the concentration of the sodium carbonate aqueous solution is 25-35%.

[0022] like Figure 1 As shown, in order to facilitate the weighing and feeding of activated carbon, an activated carbon weight loss scale 9 is connected to the top of the regenerated carbon washing tank 3.

[0023] like Figure 1 As shown, in order to achieve continuous regeneration and improve the regeneration efficiency of tributyl phosphate extractant, the connecting pipeline between the regeneration alkali washing tank 2 and the regeneration carbon washing tank 3 is arranged obliquely, and the top of the pipeline is connected to the regeneration alkali washing tank 2, and the two ends of the pipeline are connected to the top of the regeneration alkali washing tank 2 and the regeneration carbon washing tank 3 respectively.

Claims

1. An efficient regeneration device for tributyl phosphate extractant, characterized in that: The invention comprises an alkali solution preparation tank (1), a regeneration alkali washing tank (2), a regeneration carbon washing tank (3), a regeneration filter press (4), a regeneration phase separation tank (5) and a regeneration water washing tower (6) which are connected in sequence through pipelines. The alkali solution preparation tank (1), the regeneration alkali washing tank (2) and the regeneration carbon washing tank (3) are all provided with a stirring mechanism. The regeneration alkali washing tank (2) is connected to a tributyl phosphate inlet pipe (7). The top of the regeneration phase separation tank (5) is connected to the bottom of the regeneration water washing tower (6). The top of the regeneration water washing tower (6) is connected to a desalted water inlet pipe (10). The top and bottom of the regeneration water washing tower (6) are also respectively connected to an extractant outlet pipe (11) and a dilute waste alkali solution outlet pipe (13).

2. A high-efficiency regeneration device for tributyl phosphate extractant as claimed in claim 1, characterized in that: The alkali solution preparation tank (1) is provided with a heating structure and a temperature control structure, and the temperature of the sodium carbonate aqueous solution prepared in the alkali solution preparation tank (1) is 50-65°C.

3. A high-efficiency regeneration device for tributyl phosphate extractant as claimed in claim 2, characterized in that: The concentration of the sodium carbonate aqueous solution is 25-35%.

4. The high-efficiency regeneration device of tributyl phosphate extractant as claimed in claim 1, characterized in that: The top of the regenerated carbon washing tank (3) is connected to an activated carbon weight loss scale (9).

5. A high-efficiency regeneration device for tributyl phosphate extractant as claimed in claim 1, characterized in that: The connecting pipe between the regeneration alkali washing tank (2) and the regeneration carbon washing tank (3) is arranged obliquely, and the top of the pipe is connected to the regeneration alkali washing tank (2), and the two ends of the pipe are respectively connected to the top of the regeneration alkali washing tank (2) and the top of the regeneration carbon washing tank (3).

Images