Waste sodium hypochlorite acid waste gas treatment system

Abstract

The utility model discloses a waste sodium hypochlorite acid waste gas treatment system which comprises a venturi, a sodium hypochlorite storage tank, a sodium hypochlorite head tank, a second cleaning tower, a first cleaning tower, a water washing tower, a spray tower, a sodium hypochlorite desorption tower, a sodium hypochlorite buffer tank, a spiral plate heat exchanger, a closed water cooling tower, a sodium hypochlorite storage tank and a sodium hypochlorite recycling tank, the output end of the venturi is fixedly connected and communicated with the input end of the sodium hypochlorite storage tank through a pipeline, the output end of the sodium hypochlorite storage tank is fixedly connected and communicated with the input end of the sodium hypochlorite head tank through a pipeline, the position of the spiral plate heat exchanger in the technological process is adjusted, and the spiral plate heat exchanger is arranged behind the open type water cooling tower. The spiral plate heat exchanger is arranged in front of the closed water cooling tower, and the open water cooling tower is changed into the closed water cooling tower, so that the defect of aeration of the open water cooling tower is eliminated, the escape amount of acid gas in the waste sodium hypochlorite solution is greatly reduced, and the influence of the waste sodium hypochlorite solution on the field environment is improved.

Description

Technical field:

[0001] The utility model relates to the technical field of acetylene PVC sodium hypochlorite purification by calcium carbide method, and in particular to a waste sodium hypochlorite acid waste gas treatment system. Background technology:

[0002] Acetylene is the simplest alkyne. It is a flammable gas. It is in danger of violent explosion in liquid and solid state or in gaseous state under certain pressure. Heat, vibration, electric spark and other factors can cause explosion. Therefore, it cannot be stored or transported after pressurized liquefaction. It is insoluble in water but soluble in acetone. At 15°C and a total pressure of 15 atmospheres, its solubility in acetone is 237 g / L, and the solution is stable. Therefore, in industry, acetylene is pressed into steel drums or steel tanks filled with porous materials such as asbestos after the porous materials absorb acetone for storage and transportation.

[0003] Acetylene produced by the calcium carbide process contains impurities such as hydrogen sulfide and phosphine.

[0004] At present, crude acetylene produced by the calcium carbide method must first pass through a spray tower, a water washing tower, a purification tower 1 and a purification tower 2 in sequence.

[0005] Excess sodium hypochlorite (abbreviated as sodium hypochlorite) passes through the second purification tower, the first purification tower, the washing water washing tower, and the spray tower in turn to react with H2S and PH3 in the crude acetylene to convert it into dilute sulfuric acid and dilute phosphoric acid.

[0006] The acetylene gas from which hydrogen sulfide and phosphine have been removed enters the neutralization tower for alkaline washing and neutralization.

[0007] The sodium hypochlorite solution (45℃-50℃) after the reaction is sent to the desorption tower to evaporate acetylene (recovery volume is about 65m 3 / h), and then the waste sodium solution is cooled by the sodium spiral plate heat exchanger and then enters the venturi with chlorine and 10% NaOH solution to be configured as sodium and enter the sodium storage tank. The sodium storage tank is transported to the sodium high-level tank through a lifting pump, and the sodium in the sodium high-level tank is then sent to the second purification tower for recycling.

[0008] In actual process production, according to the physical properties of acetylene, the solubility of acetylene is best at 15°C. However, in the cooling process, it is found that the cooling effect of the existing process is not particularly ideal. In particular, acid gas leakage will occur during the cooling process. Although the workers carry respiratory purifiers, long-term work will inevitably cause damage to their health, and the leakage of acid gas will easily affect the surrounding environment. Utility model content:

[0009] The utility model aims to provide a waste sodium hypochlorite acid waste gas treatment system.

[0010] The utility model is implemented by the following technical solutions:

[0011] A waste sodium hypochlorite acid waste gas treatment system, comprising a venturi, a hypochlorite storage tank, a hypochlorite high-level tank, a second cleaning tower, a first cleaning tower, a water washing tower, a spray tower, a hypochlorite separation tower, a hypochlorite buffer tank, a spiral plate heat exchanger, a closed cooling tower, a hypochlorite water storage tank and a hypochlorite recycling tank, wherein the output end of the venturi is fixedly connected and communicated with the input end of the hypochlorite storage tank through a pipeline, the output end of the hypochlorite storage tank is fixedly connected and communicated with the input end of the hypochlorite high-level tank through a pipeline, the output end of the hypochlorite high-level tank is fixedly connected and communicated with the input end of the second cleaning tower through a pipeline, the output end of the second cleaning tower is fixedly connected and communicated with the input end of the first cleaning tower through a pipeline, and the output end of the first cleaning tower is fixedly connected to the input end of the water washing tower through a pipeline The output end of the water washing tower is fixedly connected and communicated with the input end of the spray tower through a pipeline, the output end of the spray tower is fixedly connected and communicated with the input end of the secondary sodium desorption tower through a pipeline, the output end of the secondary sodium desorption tower is fixedly connected and communicated with the input end of the secondary sodium buffer tank through a pipeline, the output end of the secondary sodium buffer tank is fixedly connected and communicated with the input end of the spiral plate heat exchanger through a pipeline, the output end of the spiral plate heat exchanger is fixedly connected and communicated with the input end of the closed cooling water tower through a pipeline, the output end of the closed cooling water tower is communicated with the secondary sodium water storage tank through a pipeline, the output end of the secondary sodium water storage tank is communicated with the input end of the secondary sodium reuse tank through a pipeline, and the output end of the secondary sodium reuse tank is fixedly connected and communicated with the input end of the venturi through a pipeline.

[0012] Preferably, a waste gas branch pipe is arranged above the sub-sodium water storage tank, one end of which is fixedly connected to and communicated with the waste gas main pipe, and an arc-shaped air suction hood is arranged above the sub-sodium water storage tank, and the arc-shaped air suction hood is fixedly installed on one end of the conveying pipeline between the closed cooling tower and the sub-sodium water storage tank.

[0013] Preferably, the inner wall of the arc-shaped air suction hood is coated with an anti-corrosion layer, and a plurality of multi-way tubes are fixedly connected to the side wall of the bottom end of the exhaust gas branch pipe, and the bottom ends of the plurality of multi-way tubes are respectively fixedly connected to and communicate with the arc-shaped air suction hood.

[0014] The advantages of the utility model are as follows: the position of the spiral plate heat exchanger in the process flow is adjusted, from being placed after the open cooling tower to being placed before the closed cooling tower, which is more conducive to a rapid drop in the temperature of the spent sodium solution and an increase in the solubility of the acidic gas. The open cooling tower is changed into a closed cooling tower, eliminating the disadvantage of "aeration" of the open cooling tower, greatly reducing the amount of acidic gas emitted in the spent sodium solution, reducing the amount of acidic gas emitted, and thus improving the impact of the spent sodium solution on the on-site environment. Description of the drawings:

[0015] Figure 1 It is a process flow chart of the structure of the utility model;

[0016] Figure 2 It is a schematic diagram of the positions of the secondary sodium water storage tank and the exhaust gas branch pipe in the structure of the utility model;

[0017] Figure 3 It is a side view of the arc-shaped air suction hood in the structure of the utility model.

[0018] In the figure: venturi 1, secondary sodium storage tank 2, secondary sodium high-level tank 3, purification tower 2 4, purification tower 1 5, water washing tower 6, spray tower 7, secondary sodium separation tower 8, secondary sodium buffer tank 9, spiral plate heat exchanger 10, closed cooling tower 11, secondary sodium water storage tank 12, secondary sodium reuse tank 13, arc suction hood 14, multi-way pipe 15. Specific implementation method:

[0019] like Figures 1 to 3 As shown, a waste sodium hypochlorite acid waste gas treatment system includes a venturi 1, a sub-sodium storage tank 2, a sub-sodium high-level tank 3, a second cleaning tower 4, a first cleaning tower 5, a water washing tower 6, a spray tower 7, a sub-sodium separation tower 8, a sub-sodium buffer tank 9, a spiral plate heat exchanger 10, a closed cooling tower 11, a sub-sodium water storage tank 12 and a sub-sodium recycling tank 13. The output end of the venturi 1 is fixedly connected and communicated with the input end of the sub-sodium storage tank 2 through a pipeline, the output end of the sub-sodium storage tank 2 is fixedly connected and communicated with the input end of the sub-sodium high-level tank 3 through a pipeline, the output end of the sub-sodium high-level tank 3 is fixedly connected and communicated with the input end of the second cleaning tower 4 through a pipeline, the output end of the second cleaning tower 4 is fixedly connected and communicated with the input end of the first cleaning tower 5 through a pipeline, the output end of the first cleaning tower 5 is fixedly connected and communicated with the input end of the water washing tower 6 through a pipeline, and the output end of the water washing tower 6 is connected to the input end of the spray tower 7 through a pipeline. The output end of the spray tower 7 is fixedly connected and communicated with the input end of the secondary sodium desorption tower 8 through a pipeline, the output end of the secondary sodium desorption tower 8 is fixedly connected and communicated with the input end of the secondary sodium buffer tank 9 through a pipeline, the output end of the secondary sodium buffer tank 9 is fixedly connected and communicated with the input end of the spiral plate heat exchanger 10 through a pipeline, the output end of the spiral plate heat exchanger 10 is fixedly connected and communicated with the input end of the closed cooling tower 11 through a pipeline, the output end of the closed cooling tower 11 is communicated with the secondary sodium water storage tank 12 through a pipeline, the output end of the secondary sodium water storage tank 12 is communicated with the input end of the secondary sodium reuse tank 13 through a pipeline, and the output end of the secondary sodium reuse tank 13 is fixedly connected and communicated with the input end of the venturi 1 through a pipeline. The specific process flow is: first, the excess secondary sodium solution flows in the purification tower 2 4, the purification tower 1 5, the water washing tower 6 and the spray tower 7 along each pipeline in turn, and the attached Figure 1It can be seen that the crude acetylene is reversed through the spray tower 7, the water washing tower 6, the first purification tower 5 and the second purification tower 4, and then the hyposodium solution reacts with the H2S and PH3 in the crude acetylene to convert it into dilute sulfuric acid and dilute phosphoric acid. The acetylene gas after the reaction enters the next neutralization process, that is, the acetylene gas with hydrogen sulfide and phosphine removed enters the neutralization tower for alkaline washing and neutralization, while the hyposodium solution at this time contains dilute sulfuric acid and dilute phosphoric acid, that is, it contains acidic gas. The hyposodium solution containing dilute sulfuric acid and dilute phosphoric acid enters the hyposodium precipitation tower 8 in the process to precipitate the incompletely decomposed acetylene (the acetylene recovery volume is about 65m 3 / h), the hyposodium solution containing acidic gas at this time enters the hyposodium buffer tank 9 for buffering, and enters the next step of the process, the spiral plate heat exchanger 10 for heat exchange cooling, and then passes through the closed cooling tower 11 for secondary cooling, and then enters the hyposodium water storage tank 12 for re-proportioning to form a qualified hyposodium solution, and finally enters the hyposodium reuse tank 13, and then is transported to the venturi 1 through a pipeline for repeated use. In this way, the position of the spiral plate heat exchanger in the process flow is adjusted, from the previous spiral plate heat exchanger being placed after the open cooling tower to the spiral plate heat exchanger being placed before the closed cooling tower, which is more conducive to the rapid reduction of the temperature of the spent hyposodium solution and the increase of the solubility of the acidic gas, and the open cooling tower is changed to a closed cooling tower, eliminating the disadvantage of the open cooling tower "aeration", greatly reducing the escape amount of acidic gas in the spent hyposodium solution, reducing the escape amount of acidic gas, thereby improving the impact of the spent hyposodium solution on the on-site environment.

[0020] A waste gas branch pipe is arranged above the secondary sodium water storage tank 12, one end of which is fixedly connected to and communicated with the waste gas main pipe. An arc-shaped air suction hood 14 is arranged above the secondary sodium water storage tank 12, and the arc-shaped air suction hood 14 is fixedly installed on one end of the conveying pipeline between the closed cooling tower 11 and the secondary sodium water storage tank 12. The waste gas branch pipe is connected to the waste gas main pipe, and the waste gas main pipe conveys the waste gas to the purification and emission process. The traditional trumpet-shaped air suction hood is changed to an arc-shaped air suction hood 14 to further increase the air suction area, and the arc-shaped air suction hood 14 is arranged at the end of the pipeline outlet, so that the waste gas is absorbed from the source to avoid further escape of acidic gas into the workshop.

[0021] The inner wall of the arc-shaped air suction hood 14 is coated with an anti-corrosion layer, and a plurality of multi-way tubes 15 are fixedly connected to the side wall of the bottom end of the exhaust gas branch pipe. The bottom ends of the plurality of multi-way tubes 15 are respectively fixedly connected to and communicate with the arc-shaped air suction hood 14. The anti-corrosion layer can effectively delay the corrosion of the acidic gas, and the arrangement of the plurality of multi-way tubes 15 can effectively disperse the suction force at the exhaust gas branch pipe and disperse it in the arc-shaped air suction hood 14, so that the acidic gas can be effectively absorbed, thereby reducing the escape of the acidic gas into the surrounding environment.

[0022] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A waste sodium hypochlorite acid waste gas treatment system, characterized in that: It includes a venturi, a secondary sodium storage tank, a secondary sodium high-level tank, a second cleaning tower, a first cleaning tower, a water washing tower, a spray tower, a secondary sodium separation tower, a secondary sodium buffer tank, a spiral plate heat exchanger, a closed cooling tower, a secondary sodium water storage tank and a secondary sodium recycling tank. The output end of the venturi is fixedly connected and communicated with the input end of the secondary sodium storage tank through a pipeline, the output end of the secondary sodium storage tank is fixedly connected and communicated with the input end of the secondary sodium high-level tank through a pipeline, the output end of the secondary sodium high-level tank is fixedly connected and communicated with the input end of the second cleaning tower through a pipeline, the output end of the second cleaning tower is fixedly connected and communicated with the input end of the first cleaning tower through a pipeline, the output end of the first cleaning tower is fixedly connected and communicated with the input end of the water washing tower through a pipeline, and the output end of the water washing tower is fixedly connected and communicated with the input end of the second cleaning tower. The output end is fixedly connected and communicated with the input end of the spray tower through a pipeline, the output end of the spray tower is fixedly connected and communicated with the input end of the secondary sodium desorption tower through a pipeline, the output end of the secondary sodium desorption tower is fixedly connected and communicated with the input end of the secondary sodium buffer tank through a pipeline, the output end of the secondary sodium buffer tank is fixedly connected and communicated with the input end of the spiral plate heat exchanger through a pipeline, the output end of the spiral plate heat exchanger is fixedly connected and communicated with the input end of the closed cooling tower through a pipeline, the output end of the closed cooling tower is communicated with the secondary sodium water storage tank through a pipeline, the output end of the secondary sodium water storage tank is communicated with the input end of the secondary sodium reuse tank through a pipeline, and the output end of the secondary sodium reuse tank is fixedly connected and communicated with the input end of the venturi through a pipeline.

2. A waste sodium hypochlorite acid waste gas treatment system according to claim 1, characterized in that: A waste gas branch pipe is arranged above the sub-sodium water storage tank, one end of which is fixedly connected and communicated with the waste gas main pipe. An arc-shaped air suction hood is arranged above the sub-sodium water storage tank, and the arc-shaped air suction hood is fixedly installed on one end of the conveying pipeline between the closed cooling tower and the sub-sodium water storage tank.

3. A waste sodium hypochlorite acid waste gas treatment system according to claim 2, characterized in that: The inner wall of the arc-shaped air suction hood is coated with an anti-corrosion layer, and a plurality of multi-way pipes are fixedly connected to the side wall of the bottom end of the exhaust gas branch pipe, and the bottom ends of the plurality of multi-way pipes are respectively fixedly connected to and communicate with the arc-shaped air suction hood.

Images