Phosphorus pentachloride production tail gas purification system

Abstract

The utility model discloses a phosphorus pentachloride production tail gas purification system which comprises an alkali liquor tower, a spray tower and an adsorption tank, the alkali liquor tower, the spray tower and the adsorption tank are communicated, the bottom of the side wall of the alkali liquor tower is communicated with a gas inlet pipe, the gas inlet pipe is communicated with a bag-type dust remover, the top of the side wall of the alkali liquor tower is communicated with an alkali liquor pipe, the top of the alkali liquor tower is communicated with a gas guide pipe I, and the gas guide pipe I is communicated with a gas guide pipe II. One end of the gas guide pipe I is communicated with the bottom of the side wall of the spray tower, the top of the spray tower is communicated with a gas guide pipe II, one end of the gas guide pipe II is communicated with the bottom of the side wall of the adsorption tank, a sieve tray I and a sieve tray II are arranged in the adsorption tank, and activated carbon is placed on the sieve tray I and the sieve tray II. The tail gas is comprehensively and efficiently treated through the multi-stage purification units such as the alkali liquor tower, the spray tower and the adsorption tank, the excessive high adsorption saturation speed of activated carbon is avoided through the multi-stage purification units, the energy consumption cost of the activated carbon is reduced, and resources are saved.

Description

Technical Field

[0001] This application relates to the technical field of tail gas treatment, and particularly relates to a purification system for the tail gas produced in the production of phosphorus pentachloride. Background Art

[0002] Phosphorus pentachloride is an inorganic compound, which is a pale yellow crystalline powder with a pungent odor. The preparation of phosphorus pentachloride usually involves vaporizing liquid chlorine and then passing it into a chlorine drying tower for dehydration treatment to obtain dry chlorine gas. Subsequently, the dry chlorine gas is passed into a reactor and undergoes a chlorination reaction with liquid phosphorus trichloride. During the reaction process, chlorine gas needs to be continuously passed in until the reaction liquid changes from a solution state to a completely dry crystalline product, that is, the finished product of phosphorus pentachloride is obtained. The tail gas generated during the industrial production of phosphorus pentachloride mainly contains some harmful substances and needs to be treated before being discharged into the environment. Currently, some existing equipment uses activated carbon to adsorb and purify the tail gas generated by phosphorus pentachloride. However, the adsorption efficiency of activated carbon is limited, resulting in poor waste gas treatment effects. The adsorption capacity of activated carbon is also limited, and the saturation speed is too fast, which will increase the energy consumption cost. Summary of the Utility Model

[0003] This application provides a purification system for the tail gas produced in the production of phosphorus pentachloride. The system is provided with an alkali liquor tower, a spray tower, and an adsorption tank. After the generated tail gas is introduced into the alkali liquor tower, it contacts the alkali liquor in the tower, thereby neutralizing the acidic components in the tail gas. The tail gas treated by the alkali liquor tower enters the water tower and further contacts water to remove the residual pollutants in the tail gas. The treated tail gas enters the adsorption tank and is fully contacted and adsorbed by the activated carbon in the tank to further purify the harmful substances in the tail gas. Through multi-stage purification units such as the alkali liquor tower, the spray tower, and the adsorption tank, comprehensive and efficient treatment of the tail gas is achieved. Moreover, the multi-stage purification units avoid the too-fast saturation speed of activated carbon adsorption, reduce the energy consumption cost of activated carbon, and save resources.

[0004] The present application provides a purification system for the tail gas in the production of phosphorus pentachloride, comprising: an alkali solution tower, a spray tower, and an adsorption tank. The alkali solution tower, the spray tower, and the adsorption tank are connected to each other. The bottom of the side wall of the alkali solution tower is connected to an intake pipe, and the intake pipe is connected to a bag filter. One end of the intake pipe is connected to a reaction kettle. The top of the side wall of the alkali solution tower is connected to an alkali solution pipe, and the alkali solution pipe is connected to a water pump I. One end of the alkali solution pipe is connected to an alkali solution tank, and the other end of the alkali solution pipe is connected to a spray pipe. A number of atomizing nozzles are evenly arranged on the spray pipe. The top of the alkali solution tower is connected to a gas guide pipe I, and the gas guide pipe I is connected to an exhaust fan I. One end of the gas guide pipe I is connected to the bottom of the side wall of the spray tower. The top of the side wall of the spray tower is connected to a water pipe, and the water pipe is connected to a water pump II. One end of the water pipe is connected to a water tank, and the other end of the water pipe is connected to a spray pipe. The top of the spray tower is connected to a gas guide pipe II, and the gas guide pipe II is connected to an exhaust fan II. One end of the gas guide pipe II is connected to the bottom of the side wall of the adsorption tank. Two sieve trays are arranged in the adsorption tank. The sieve trays include sieve tray I and sieve tray II. Activated carbon is placed on sieve tray I and sieve tray II. A clamping groove is respectively arranged on the inner wall of the adsorption tank corresponding to the positions of the two sieve trays. A window is respectively arranged on the adsorption tank corresponding to each sieve tray. Sealing gaskets are arranged on the side wall of the adsorption tank corresponding to the edges of the windows. A handle is respectively arranged on the side wall of each sieve tray. An exhaust pipe is arranged on the top of the adsorption tank;

[0005] An external PLC controller is connected to the alkali solution tower, the spray tower, and the adsorption tank. The bag filter, each water pump, and each exhaust fan are electrically connected to the PLC controller.

[0006] Further, the spray pipe is spirally suspended and hung in the alkali solution tower and the spray tower.

[0007] Further, the cross-sectional area of each sieve tray is smaller than the cross-sectional area of the corresponding window.

[0008] Further, the diameter of the activated carbon particles placed on sieve tray I is larger than the diameter of the activated carbon particles placed on sieve tray II.

[0009] Further, a drain pipe is respectively arranged at the bottom of the side walls of the alkali solution tower and the spray tower, and a solenoid valve is installed on each drain pipe. The solenoid valve is electrically connected to the PLC controller.

[0010] Further, a number of operation buttons are arranged on the PLC controller.

[0011] As can be seen from the above technical solutions, the present application provides a purification system for the tail gas of phosphorus pentachloride production, including: an alkali solution tower, a spray tower, and an adsorption tank. The alkali solution tower, the spray tower, and the adsorption tank are connected to each other. The bottom of the side wall of the alkali solution tower is connected to an intake pipe, and the intake pipe is connected to a bag filter. One end of the intake pipe is connected to a reaction kettle. During the process of the reaction kettle producing phosphorus pentachloride, the PLC controller controls the bag filter to open. Before the tail gas generated during the production process enters the alkali solution tower, it is acted upon by the bag filter to filter the dust and particulate matter in the tail gas, reduce the pollution of the environment by dust, and facilitate the subsequent equipment to remove other impurities in the tail gas. The tail gas after being dust-removed by the bag filter enters the alkali solution tower through the intake pipe. The top of the side wall of the alkali solution tower is connected to an alkali solution pipe, and the alkali solution pipe is connected to a water pump I. One end of the alkali solution pipe is connected to an alkali solution tank, and the other end of the alkali solution pipe is connected to a spray pipe. A number of atomizing nozzles are evenly arranged on the spray pipe. The PLC controller controls the water pump I to open. Under the action of the water pump I, the alkaline liquid in the alkali solution tank flows along the alkali solution pipe into the spray pipe. Under the pressurization of the water pump I, it is sprayed out from a number of atomizing nozzles on the spray pipe to spray the tail gas entering the alkali solution tower, making it contact with the alkaline solution in the tower, thereby neutralizing the acidic components in the tail gas and performing the first purification on the components of the tail gas. The top of the alkali solution tower is connected to a guide pipe I, and the guide pipe I is connected to a suction fan I. One end of the guide pipe I is connected to the bottom of the side wall of the spray tower. The top of the side wall of the spray tower is connected to a water pipe, and the water pipe is connected to a water pump II. One end of the water pipe is connected to a water tank, and the other end of the water pipe is connected to a spray pipe. The PLC controller controls the suction fan I and the water pump II to open. Under the action of the suction fan I, the tail gas that has been first purified by spraying in the alkali solution tower enters the spray tower along the guide pipe I. At the same time, under the action of the water pump II, the water in the water tank flows along the water pipe into the spray pipe. Under the pressurization of the water pump II, it is sprayed out from a number of atomizing nozzles on the spray pipe to spray the tail gas entering the spray tower, making it further contact with water to remove the residual pollutants in the tail gas and perform the second purification on the components of the tail gas. The top of the spray tower is connected to a guide pipe II, and the guide pipe II is connected to a suction fan II. One end of the guide pipe II is connected to the bottom of the side wall of the adsorption tank. Two sieve trays are arranged in the adsorption tank. The sieve trays include sieve tray I and sieve tray II. Activated carbon is placed on sieve tray I and sieve tray II. The PLC controller controls the suction fan II to open. The tail gas that has been secondarily purified in the spray tower enters the adsorption tank along the guide pipe II under the action of the suction fan II. First, the activated carbon with a large diameter in sieve tray I in the adsorption tank adsorbs it. After adsorption, the tail gas rises and is secondarily adsorbed by the activated carbon with a small diameter in sieve tray II, thereby improving the overall adsorption efficiency of the activated carbon and achieving a better adsorption effect. Through multi-stage purification units such as the alkali solution tower, the spray tower, and the adsorption tank, comprehensive and efficient treatment of the tail gas is realized. Moreover, through the multi-stage purification units, the saturation speed of the activated carbon adsorption is avoided from being too fast, the energy consumption cost of the activated carbon is reduced, resources are saved. A clamping groove is respectively arranged at the position of the inner wall of the adsorption tank corresponding to the two sieve trays, and a window is arranged at the position of the adsorption tank corresponding to each sieve tray.Sealing gaskets are provided at the edges of the windows corresponding to the side walls of the adsorption tank. A handle is provided on the side wall of each sieve tray. The two sieve trays are placed in the corresponding card slots in the adsorption tank. The card slots support the sieve trays. The sieve trays can be conveniently pushed into or pulled out of the adsorption tank through the windows by pushing and pulling the handles. The sealing gaskets at the edges of the windows seal the sieve trays to prevent the leakage of tail gas in the adsorption tank. An exhaust pipe is provided at the top of the adsorption tank. The tail gas purified by the activated carbon in the adsorption tank is discharged through the exhaust pipe after reaching the emission standard. The alkali liquor tower, the spray tower and the adsorption tank are externally connected to a PLC controller. The bag filter, each water pump and each exhaust fan are electrically connected to the PLC controller. The PLC controller controls the on-off states of the bag filter, each water pump and each exhaust fan, thereby ensuring the smooth progress of the adsorption and purification work of the alkali liquor tower, the spray tower and the adsorption tank.

[0012] In summary, the beneficial effects produced by this application are as follows:

[0013] 1. The system is provided with an alkali liquor tower, a spray tower and an adsorption tank. Through multiple purification units such as the alkali liquor tower, the spray tower and the adsorption tank, comprehensive and efficient treatment of the tail gas is realized. Moreover, through the multiple purification units, the too-fast saturation speed of the activated carbon adsorption is avoided, the energy consumption cost of the activated carbon is reduced, and resources are saved.

[0014] 2. Two sieve trays are provided in the adsorption tank, and activated carbons with different particle diameters are placed on the two sieve trays to perform secondary adsorption on the tail gas entering the adsorption tank, and the purification effect is better.

[0015] 3. The system is provided with a bag filter. Before the produced tail gas enters the alkali liquor tower, the dust and particulate matter in the tail gas are filtered by the bag filter, reducing the environmental pollution caused by dust and facilitating the removal of other impurities in the tail gas by subsequent equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of this application, the drawings required for use in the implementation cases will be briefly introduced below. Obviously, for those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative efforts.

[0017] Figure 1 It is a schematic structural diagram of this application.

[0018] Figure 2 It is a schematic structural diagram of the spray pipe.

[0019] Figure 3 It is a schematic structural diagram of the PLC controller.

[0020] Illustration of the drawings:

[0021] Among them, 1 - lye tower, 2 - spray tower, 3 - adsorption tank, 4 - intake pipe, 5 - bag filter, 6 - lye pipe, 7 - water pump 1, 8 - spray pipe, 9 - atomizing nozzle, 10 - gas guide pipe 1, 11 - exhaust fan 1, 12 - water pipe, 13 - gas guide pipe 2, 14 - exhaust fan 2, 15 - clamping groove, 16 - sieve plate 1, 17 - sieve plate 2, 18 - gasket, 19 - handle, 20 - exhaust pipe, 21 - PLC controller. Specific implementation mode

[0022] In order to enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.

[0023] It can be seen from the above technical solutions that refer to Figures 1-3 .

[0024] Example 1:

[0025] A purification system for the tail gas produced in the production of phosphorus pentachloride, comprising: an alkali solution tower 1, a spray tower 2 and an adsorption tank 3, which are connected to each other. The bottom of the side wall of the alkali solution tower 1 is connected to an intake pipe 4, and the intake pipe 4 is connected to a bag filter 5. One end of the intake pipe 4 is connected to a reaction kettle. During the process of the reaction kettle producing phosphorus pentachloride, the PLC controller 21 controls the bag filter 5 to open. Before the tail gas produced during the production process enters the alkali solution tower 1, it is affected by the bag filter 5 to filter the dust and particulate matter in the tail gas, reduce the pollution of the environment by dust, and facilitate the subsequent equipment to purify other impurities in the tail gas. The tail gas filtered by the bag filter 5 for dust enters the alkali solution tower 1 through the intake pipe 4. The top of the side wall of the alkali solution tower 1 is connected to an alkali solution pipe 6, and the alkali solution pipe 6 is connected to a water pump 7. One end of the alkali solution pipe 6 is connected to an alkali solution tank, and the other end of the alkali solution pipe 6 is connected to a spray pipe 8. A number of atomizing nozzles 9 are evenly arranged on the spray pipe 8. The PLC controller 21 controls the water pump 7 and the bag filter 5 to open simultaneously. Under the action of the water pump 7, the alkaline liquid in the alkali solution tank flows along the alkali solution pipe 6 into the spray pipe 8. Under the pressure of the water pump 7, it is sprayed out from a number of atomizing nozzles 9 on the spray pipe 8 to spray the tail gas entering the alkali solution tower 1, making it contact with the alkaline solution in the tower, thereby neutralizing the acidic components in the tail gas and purifying the components in the tail gas for the first time. The top of the alkali solution tower 1 is connected to a first guide pipe 10, and the first guide pipe 10 is connected to a first exhaust fan 11. One end of the first guide pipe 10 is connected to the bottom of the side wall of the spray tower 2. The top of the side wall of the spray tower 2 is connected to a water pipe 12, and the water pipe 12 is connected to a water pump 2. One end of the water pipe 12 is connected to a water tank, and the other end of the water pipe 12 is connected to a spray pipe 8. The PLC controller 21 controls the first exhaust fan 11 and the water pump 2 to open. Under the action of the first exhaust fan 11, the tail gas first purified by spraying in the alkali solution tower 1 flows along the first guide pipe 10 into the spray tower 2. At the same time, under the action of the water pump 2, the water in the water tank flows along the water pipe 12 into the spray pipe 8 in the spray tower 2. Under the pressure of the water pump 2, it is sprayed out from a number of atomizing nozzles 9 on the spray pipe 8 to spray the tail gas entering the spray tower 2, making it further contact with water to purify the residual pollutants in the tail gas and purify the components in the tail gas for the second time. The top of the spray tower 2 is connected to a second guide pipe 13, and the second guide pipe 13 is connected to a second exhaust fan 14. One end of the second guide pipe 13 is connected to the bottom of the side wall of the adsorption tank 3. Two sieve trays are arranged in the adsorption tank 3. The sieve trays include a first sieve tray 16 and a second sieve tray 17. Activated carbon is placed on the first sieve tray 16 and the second sieve tray 17. The PLC controller 21 controls the second exhaust fan 14 to open. The tail gas secondarily purified by the spray tower 2 enters the adsorption tank 3 along the second guide pipe 13 under the action of the second exhaust fan 14. The activated carbon with a large diameter in the first sieve tray 16 in the adsorption tank 3 first adsorbs the tail gas. After adsorption, the tail gas rises and is secondarily adsorbed by the activated carbon with a small diameter in the second sieve tray 17. The activated carbon with different diameters on the two sieve trays adsorbs successively, improving the overall adsorption efficiency of the activated carbon and having a better adsorption effect.Through multi-stage purification units such as the lye tower 1, the spray tower 2, and the adsorption tank 3, comprehensive and efficient treatment of the tail gas is achieved. Moreover, through the multi-stage purification units, the too-fast saturation speed of activated carbon adsorption is avoided, the energy consumption cost of the activated carbon is reduced, resources are saved. At positions on the inner wall of the adsorption tank 3 corresponding to the two sieve trays, a clamping groove 15 is respectively provided. At positions corresponding to each sieve tray in the adsorption tank 3, a window is provided. Sealing gaskets 18 are provided on the side wall of the adsorption tank 3 corresponding to the edges of the windows. A handle 19 is provided on the side wall of each sieve tray. The two sieve trays are clamped in the corresponding clamping grooves 15 in the adsorption tank 3. The clamping grooves 15 play a supporting role for the sieve trays. The sieve trays can be conveniently pushed into or pulled out of the adsorption tank 3 through the windows by pushing and pulling the handles 19. The sealing gaskets 18 at the edges of the windows play a sealing role for the sieve trays, preventing the leakage of the tail gas in the adsorption tank 3. A discharge pipe 20 is provided at the top of the adsorption tank 3. After the tail gas purified by the activated carbon in the adsorption tank 3 reaches the emission standard, it is discharged through the discharge pipe 20;

[0026] The lye tower 1, the spray tower 2, and the adsorption tank 3 are externally connected to a PLC controller 21. The bag filter 5, each water pump, and each exhaust fan are electrically connected to the PLC controller 21. The PLC controller 21 controls the on-off states of the bag filter 5, each water pump, and each exhaust fan, thereby ensuring the smooth progress of the adsorption and purification work of the lye tower 1, the spray tower 2, and the adsorption tank 3.

[0027] As a preferred implementation method, the spray pipe 8 is suspended in a spiral shape in the lye tower 1 and the spray tower 2, so that the atomizing nozzles 9 on the spray pipe 8 are evenly distributed inside the two tower bodies, thereby uniformly atomizing and spraying the tail gas entering the tower bodies and improving the spraying area.

[0028] As a preferred implementation method, the cross-sectional area of each sieve tray is smaller than the cross-sectional area of the corresponding window, which facilitates the entry and exit of the sieve trays through the windows.

[0029] As a preferred implementation method, the diameter of the activated carbon particles placed on the sieve tray 16 is larger than the diameter of the activated carbon particles placed on the sieve tray 17. The activated carbon particles with a larger diameter on the sieve tray 16 have larger pore diameters inside, which is beneficial for adsorbing impurities or pollutants with larger molecules in the tail gas. The activated carbon particles with a smaller diameter are used on the sieve tray 17, and their internal pore diameters are relatively smaller, which is more suitable for adsorbing small molecule substances, helping to achieve the hierarchical adsorption of different-sized molecules in the tail gas and improving the overall adsorption efficiency.

[0030] As a preferred implementation method, a drain pipe is provided at the bottom of the side walls of the lye tower 1 and the spray tower 2. An electromagnetic valve is installed on each drain pipe. The electromagnetic valve is electrically connected to the PLC controller 21. When the lye tower 1 and the spray tower 2 complete the tail gas spraying, the PLC controller 21 controls the electromagnetic valves on the drain pipes of the lye tower 1 and the spray tower 2 to open, discharges the liquid in the two tower bodies, and then conducts treatment.

[0031] As a preferred implementation manner, a number of operation buttons are provided on the PLC controller 21, and the number of operation buttons respectively control the on / off states of the bag filter 5, each water pump, and each exhaust fan.

[0032] Those skilled in the art will readily conceive of other embodiments of the present application after considering the specification and practicing the application disclosed herein. The present application is intended to cover any variations, uses, or adaptations of the present application, which follow the general principles of the present application and include known common knowledge or conventional technical means in the technical field not disclosed in the present application. The specification and examples are only regarded as exemplary, and the true scope of the present application is pointed out by the claims.

[0033] It should be understood that the present application is not limited to the exact structures already described and shown in the drawings, and various modifications and changes can be made without departing from its scope. The above-described embodiments of the present application do not constitute a limitation on the protection scope of the present application.

Claims

1. A tail gas purification system for phosphorus pentachloride production, characterized in that: include: An alkali liquid tower (1), a spray tower (2) and an adsorption tank (3), wherein the alkali liquid tower (1), the spray tower (2) and the adsorption tank (3) are connected to each other, the bottom of the side wall of the alkali liquid tower (1) is connected to an air intake pipe (4), the air intake pipe (4) is connected to a bag dust collector (5), one end of the air intake pipe (4) is connected to a reactor, the top of the side wall of the alkali liquid tower (1) is connected to an alkali liquid pipe (6), the alkali liquid pipe (6) is connected to a water pump (7), the alkali liquid pipe ( 6) is connected to an alkali liquid tank at one end, the other end of the alkali liquid pipe (6) is connected to a spray pipe (8), a plurality of atomizing nozzles (9) are evenly arranged on the spray pipe (8), the top of the alkali liquid tower (1) is connected to an air guide pipe (10), the air guide pipe (10) is connected to an exhaust fan (11), one end of the air guide pipe (10) is connected to the bottom of the side wall of the spray tower (2), the top of the side wall of the spray tower (2) is connected to a water pipe (12), the water pipe (1 2) connected to water pump 2, one end of the water pipe (12) is connected to a water tank, the other end of the water pipe (12) is connected to the spray pipe (8), the top of the spray tower (2) is connected to air guide pipe 2 (13), the air guide pipe 2 (13) is connected to exhaust fan 2 (14), one end of the air guide pipe 2 (13) is connected to the bottom of the side wall of the adsorption tank (3), the adsorption tank (3) is provided with two sieve trays, the sieve trays include sieve tray 1 (16) and sieve tray 2 (17), the Activated carbon is placed on the sieve plate 1 (16) and the sieve plate 2 (17); a slot (15) is provided at the inner wall of the adsorption tank (3) at the position corresponding to the two sieve plates; a window is provided at the position corresponding to each sieve plate of the adsorption tank (3); a sealing gasket (18) is provided at the side wall of the adsorption tank (3) at the edge of the window; a handle (19) is provided on the side wall of each sieve plate; and an exhaust pipe (20) is provided at the top of the adsorption tank (3); The alkali liquid tower (1), the spray tower (2) and the adsorption tank (3) are externally connected to a PLC controller (21), and the bag filter (5), each of the water pumps, and each of the exhaust fans are electrically connected to the PLC controller (21).

2. A phosphorus pentachloride production tail gas purification system according to claim 1, characterized in that: The spray pipe (8) is suspended in a spiral shape inside the alkali liquid tower (1) and the spray tower (2).

3. A phosphorus pentachloride production tail gas purification system according to claim 1, characterized in that: The cross-sectional area of ​​each sieve plate is smaller than the cross-sectional area of ​​the corresponding window.

4. A phosphorus pentachloride production tail gas purification system according to claim 1, characterized in that: The diameter of the activated carbon particles placed on the sieve plate one (16) is greater than the diameter of the activated carbon particles placed on the sieve plate two (17).

5. A phosphorus pentachloride production tail gas purification system according to claim 1, characterized in that: The bottom of the side wall of the alkali liquid tower (1) and the spray tower (2) are both provided with a drainage pipe, and each drainage pipe is installed with a solenoid valve, and the solenoid valve is electrically connected to the PLC controller (21).

6. A phosphorus pentachloride production tail gas purification system according to claim 1, characterized in that: The PLC controller (21) is provided with a plurality of operation buttons.

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