Wastewater recycling system in triisobutyl phosphate production

Abstract

The utility model relates to the technical field of triisobutyl phosphate production, in particular to a wastewater recycling system in triisobutyl phosphate production. The wastewater recycling system in the triisobutyl phosphate production comprises a wastewater collecting tank, the wastewater collecting tank is connected with a distillation tower through a filter, the distillation tower is connected with a cooler through a pre-cooling tank, a pre-cooling tank coil pipe is arranged in the pre-cooling tank, and a cooler coil pipe is arranged in the cooler. According to the system, through cooperative use of the filter and the distillation tower, raw materials in wastewater are recycled after solid waste is removed, so that the utilization rate of the raw materials is greatly increased, the economic benefit is increased, and repeated treatment is avoided; through cooperative use of the pre-cooling tank and the cooler, the low-temperature wastewater without sodium chloride is used for pre-cooling before the wastewater enters the cooler, so that the cooling energy consumption is greatly reduced, and the wastewater treatment efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of triisobutyl phosphate production, in particular to a wastewater recycling system in the production of triisobutyl phosphate. Background Art

[0002] Triisobutyl phosphate is a colorless to pale yellow liquid with low volatility and relatively unstable chemical properties. It is easily decomposed when heated or exposed to light. The preparation method of triisobutyl phosphate usually involves an ester exchange reaction, in which isobutanol and phosphorus oxychloride react under controlled conditions to produce triisobutyl phosphate. During the production process, isobutanol is first added to the reactor and cooled, and then phosphorus oxychloride is slowly added dropwise, controlling the reaction temperature to no more than 20°C. After the reaction is completed, the temperature is raised to 65-70°C to continue the reaction. After that, the excess alcohol and hydrogen chloride azeotropic mixture are recovered by vacuum distillation. After the crude product is washed and dried, the fractions are collected by vacuum distillation to obtain triisobutyl phosphate with a purity of more than 99%. However, a large amount of wastewater is generated during production.

[0003] In workshop production, triisobutyl phosphate wastewater contains impurities such as unreacted isobutanol, phosphorus oxychloride, sodium chloride, and solid waste catalysts. For the above impurities, in the actual treatment process, only sodium chloride is often pre-treated, resulting in wastewater treatment often not meeting standards and requiring repeated treatment, which greatly reduces treatment efficiency, wastes a lot of raw materials, and causes economic losses. Utility Model Content

[0004] In view of the above deficiencies in the prior art, the purpose of the present invention is to provide a wastewater recycling system in the production of triisobutyl phosphate. By using a filter and a distillation tower in combination, the raw materials in the wastewater are recovered after removing the solid waste, which greatly improves the utilization rate of the raw materials, improves the economic benefits, and avoids repeated treatment; by using a pre-cooling tank and a cooler in combination, the low-temperature wastewater after removing the sodium chloride is used for pre-cooling before the wastewater enters the cooler, which greatly reduces the cooling energy consumption and improves the wastewater treatment efficiency.

[0005] The utility model is realized by adopting the following technical solutions:

[0006] The wastewater recycling system in the production of triisobutyl phosphate includes a wastewater collection tank connected to a distillation tower via a filter, the distillation tower is connected to a cooler via a pre-cooling tank, a pre-cooling tank coil is provided inside the pre-cooling tank, and a cooler coil is provided inside the cooler.

[0007] The filter adopts a "bottom-in, top-out" filtration method. The wastewater to be filtered enters from the bottom of the filter plate and is discharged from the top. Impurities will sink to the bottom of the filter due to their own gravity, reducing the probability of filter plate clogging.

[0008] The wastewater recycling system in the production of triisobutyl phosphate further comprises a refrigerator, the outlet of the refrigerator is connected to the inlet of the cooler coil, and the outlet of the cooler coil is connected to the inlet of the refrigerator.

[0009] The wastewater collection tank is connected to the filter through a filter inlet pump, and a stirring device is provided inside the wastewater collection tank.

[0010] A filter plate is provided inside the filter, and an impurity discharge port is provided outside the vertical wall of the filter.

[0011] The connection point between the filter inlet pump and the filter is located below the filter plate, the connection point of the distillation tower is located below the filter plate, and the impurity discharge port is located below the filter plate.

[0012] The distillation tower is connected with a recovery tank, and a reboiler is provided below the distillation tower.

[0013] The cooler is connected to the pre-cooling tank coil through a heat exchange pipe.

[0014] When removing sodium chloride, the wastewater is partially frozen by cooling, and then the upper layer of ice is removed. Soluble ammonium salts are added to the unfrozen wastewater to induce the crystallization and removal of sodium chloride in the wastewater.

[0015] A pre-cooling tank inlet pump is provided between the distillation tower and the pre-cooling tank, and a desuperheater inlet pump is provided between the pre-cooling tank and the desuperheater.

[0016] The working principle of this utility model is:

[0017] Wastewater from the wastewater collection tank is pumped into the filter in a "bottom-in, top-out" manner. After filtration, the wastewater enters the distillation tower, and the filtered solid waste is discharged through the impurity discharge port. The reboiler and the condenser on the distillation tower begin to operate, distilling the wastewater entering the distillation tower. After distillation, the wastewater enters the pre-cooling tank for heat exchange, and then enters the desuperheater. The refrigerator starts to operate. The wastewater treated in the desuperheater enters the pre-cooling tank coil through the heat exchange pipe for heat exchange before entering the next device. When removing sodium chloride from the desuperheater, the wastewater is partially frozen by cooling. The upper layer of ice is then removed, and a soluble ammonium salt is added to the unfrozen wastewater to induce crystallization and removal of sodium chloride in the wastewater.

[0018] Compared with the prior art, the beneficial effects of the present invention are:

[0019] By adopting the wastewater recycling system in the production of triisobutyl phosphate of the utility model, the raw materials in the wastewater are recovered after the solid waste is removed through the coordinated use of the filter and the distillation tower, which greatly improves the utilization rate of the raw materials, improves the economic benefits, and avoids repeated treatment; by cooperating with the pre-cooling tank and the cooler, the low-temperature wastewater after the sodium chloride is removed is used for pre-cooling before the wastewater enters the cooler, which greatly reduces the cooling energy consumption and improves the wastewater treatment efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic structural diagram of a wastewater recycling system for triisobutyl phosphate production according to the present invention;

[0021] In the figure: 1. Wastewater collection tank; 2. Filter; 3. Distillation tower; 4. Pre-cooling tank; 5. Desuperheater; 6. Refrigerator; 7. Filter plate; 8. Recovery tank; 9. Pre-cooling tank coil; 10. Desuperheater coil; 11. Filter inlet pump; 12. Pre-cooling tank inlet pump; 13. Desuperheater inlet pump; 14. Reboiler; 15. Heat exchange pipe; 16. Impurity discharge port. DETAILED DESCRIPTION

[0022] In order to make the purpose and technical solution of the present invention more clear, the present invention is further described in detail below with reference to the accompanying drawings.

[0023] Example 1

[0024] like Figure 1 As shown, the wastewater recycling system for triisobutyl phosphate production includes a wastewater collection tank 1 connected to a distillation tower 3 via a filter 2. The distillation tower 3 is connected to a cooler 5 via a pre-cooling tank 4. The pre-cooling tank 4 is equipped with a pre-cooling tank coil 9, and the cooler 5 is equipped with a cooler coil 10. The filter 2 utilizes a "bottom-in, top-out" filtration method, with wastewater entering from below the filter plates 7 and exiting from above. Impurities settle to the bottom of the filter 2 due to gravity, reducing the likelihood of filter plate 7 clogging. The system also includes a refrigerator 6, the outlet of which is connected to the inlet of the cooler coil 10, which in turn is connected to the inlet of the refrigerator 6. The wastewater collection tank 1 is connected to the filter 2 via a filter pump 11. A stirring device is provided within the wastewater collection tank 1. The filter 2 is equipped with filter plates 7, and an impurity discharge port 16 is provided on the outer side of the filter wall. The connection between the filter inlet pump 11 and the filter 2 is located below the filter plate 7. The connection between the distillation tower 3 is also located below the filter plate 7. The impurity discharge port 16 is also located below the filter plate 7. A recovery tank 8 is connected to the distillation tower 3, and a reboiler 14 is located below the distillation tower 3. The desuperheater 5 is connected to the pre-cooling tank coil 9 via a heat exchange pipe 15. A pre-cooling tank inlet pump 12 is installed between the distillation tower 3 and the pre-cooling tank 4, and a desuperheater inlet pump 13 is installed between the pre-cooling tank 4 and the desuperheater 5.

[0025] The above-mentioned wastewater recycling system in the production of triisobutyl phosphate, when in operation, comprises the following steps:

[0026] (1) The wastewater in the wastewater collection tank 1 enters the filter 2 in a "bottom-in, top-out" manner through the filter pump 11. After the filtration is completed, the wastewater enters the distillation tower 3, and the filtered solid waste is discharged through the impurity discharge port 16; (2) The reboiler 14 and the condenser on the distillation tower 3 start working to distill the wastewater entering the distillation tower 3. After the distillation is completed, the wastewater enters the pre-cooling tank 4 for heat exchange, and then enters the cooler 5. The refrigerator 6 starts working. After the cooling treatment, the wastewater enters the pre-cooling tank coil 9 through the heat exchange pipe 15 for heat exchange, and then enters the next device.

Claims

1. A wastewater recycling system in the production of triisobutyl phosphate, characterized in that: The invention comprises a wastewater collection tank (1), wherein the wastewater collection tank (1) is connected to a distillation tower (3) via a filter (2), and the distillation tower (3) is connected to a cooler (5) via a pre-cooling tank (4). A pre-cooling tank coil (9) is provided inside the pre-cooling tank (4), and a cooler coil (10) is provided inside the cooler (5).

2. The wastewater recycling system in the production of triisobutyl phosphate according to claim 1, characterized in that: The refrigerator also includes a refrigerator (6), the outlet of the refrigerator (6) is connected to the inlet of the cooler coil (10), and the outlet of the cooler coil (10) is connected to the inlet of the refrigerator (6).

3. The wastewater recycling system in the production of triisobutyl phosphate according to claim 1, characterized in that: The wastewater collection tank (1) is connected to the filter (2) via a filter inlet pump (11), and a stirring device is provided inside the wastewater collection tank (1).

4. The wastewater recycling system in the production of triisobutyl phosphate according to claim 3, characterized in that: A filter plate (7) is provided inside the filter (2), and an impurity discharge port (16) is provided on the outer side of the vertical wall of the filter (2).

5. The wastewater recycling system in the production of triisobutyl phosphate according to claim 4, characterized in that: The connection between the filter inlet pump (11) and the filter (2) is located below the filter plate (7), the connection between the distillation tower (3) is located below the filter plate (7), and the impurity discharge port (16) is located below the filter plate (7).

6. The wastewater recycling system in the production of triisobutyl phosphate according to claim 1, characterized in that: The distillation tower (3) is connected to a recovery tank (8), and a reboiler (14) is provided below the distillation tower (3).

7. The wastewater recycling system in the production of triisobutyl phosphate according to claim 1, characterized in that: The cooler (5) is connected to the pre-cooling tank coil (9) via a heat exchange pipe (15).

8. The wastewater recycling system in the production of triisobutyl phosphate according to claim 1, characterized in that: A pre-cooling tank inlet pump (12) is provided between the distillation tower (3) and the pre-cooling tank (4), and a desuperheater inlet pump (13) is provided between the pre-cooling tank (4) and the desuperheater (5).

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