Device for treating hypophosphorous in sodium hypochlorite wastewater production

Abstract

The invention discloses a hypophosphorous treatment device in sodium hypochlorite wastewater production. Comprising an adjusting tank for preliminarily cleaning wastewater, an ozone air floatation device connected with the adjusting tank through a wastewater lifting pump, an electro-Fenton oxidation device connected with the ozone air floatation device through a pipeline, a coagulating sedimentation device connected with the electro-Fenton oxidation device through a pipeline, and an electro-Fenton oxidation device connected with the coagulating sedimentation device through a pipeline, the coagulating sedimentation device is connected with the ozone flotation device through a pipeline, the dosing device is used for dosing the coagulating sedimentation device, and a water outlet of the coagulating sedimentation device is connected with a filter lift pump so as to discharge treated water. The ozone flotation device, the electro-Fenton oxidation device and the chemical coagulation sedimentation device are adopted to treat the high-difficulty hypophosphorous wastewater in sequence, so that the elemental phosphorus is reduced from 30 mg / l to 0.15 mg / l or below, and the wastewater is reused for production after being treated.

Description

Technical Field

[0001] The invention relates to the technical field of sewage treatment, and in particular to a device for treating phosphorus in the production of sodium-containing wastewater. Background Art

[0002] Phosphorus is a limiting factor in the eutrophication of water bodies. Phosphorus removal from wastewater is the key to controlling eutrophication of water bodies and is also one of the important ways to recover phosphorus. Treatment methods for phosphorus-containing wastewater include biological, chemical, adsorption and crystallization methods. All phosphorus removal technologies use the cyclic transformation process of phosphorus to convert phosphorus in wastewater into insoluble phosphate precipitates, or use crystallization and adsorption, or use cell synthesis to absorb phosphorus into sludge cells, and then separate these solids from the water body through separation methods such as precipitation and filtration, thereby removing phosphorus from sewage. Phosphorus usually exists in wastewater in the form of low-concentration phosphates, including organic phosphates, inorganic phosphates (mainly orthophosphates) and polyphosphates, among which orthophosphates and polyphosphates are the main forms. High-phosphorus wastewater in coal chemical wastewater is degraded by Fenton's strong oxidation, but the removal rate of hypophosphorus cannot be improved under the influence of external conditions.

[0003] Therefore, a device for treating hypophosphorus in the production of hyposodium wastewater is provided to solve the above technical problems. Summary of the invention

[0004] The purpose of the present invention is to provide a device for treating phosphorus in the production of sodium wastewater. The present invention adopts a combined process of ozone flotation and electro-Fenton to remove phosphorus wastewater to the maximum extent, thereby reducing elemental phosphorus from 30 mg / l to below 0.15 mg / l, and the wastewater is reused in production after treatment.

[0005] The object of the present invention is achieved in that:

[0006] A device for treating inferior phosphorus in the production of inferior sodium wastewater comprises a regulating tank for preliminarily cleaning the wastewater, an ozone flotation device connected to the regulating tank through a wastewater lifting pump, an electric Fenton oxidation device connected to the ozone flotation device through a pipeline, a coagulation and sedimentation device connected to the electric Fenton oxidation device through a pipeline, a mud discharge device connected to the electric Fenton oxidation device, the coagulation and sedimentation device and the ozone flotation device through a pipeline, a dosing device for dosing drugs for the coagulation and sedimentation equipment, and a water outlet of the coagulation and sedimentation device is connected to the filter lifting pump to discharge the treated water.

[0007] The ozone flotation device comprises an ozone flotation tank, an ozone gas storage tank connected to the ozone flotation tank through a pipeline and used to provide ozone to the ozone flotation tank, and a pressure pump connected to the ozone gas storage tank and the ozone flotation tank through a pipeline.

[0008] The ozone flotation tank comprises a tank body, legs located at the bottom of the tank body, and a slag suction hopper located in the tank body. The slag discharge port of the slag suction hopper passes through the tank body and is connected to a mud discharge device through a pipeline.

[0009] A releaser, a liquid inlet and a vent valve are arranged at the bottom of the pool body, and the releaser is connected with the ozone storage tank through a pipeline.

[0010] The electro-Fenton oxidation device comprises a plurality of DC electrolysis devices connected in sequence, wherein the liquid inlet of the DC electrolysis device is connected to the water outlet of the ozone flotation tank through a pipeline, the bottom of the DC electrolysis device is connected to the mud discharge device through a pipeline, and the liquid outlet of the DC electrolysis device is connected to the coagulation and sedimentation device through a pipeline.

[0011] The coagulation and sedimentation device comprises a plurality of stirring tanks, a Fenton sedimentation tank connected to the plurality of stirring tanks through pipelines, an intermediate water tank connected to the Fenton sedimentation tank through pipelines, and a filtering lifting pump connected to the drainage outlet of the intermediate water tank through pipelines.

[0012] The stirring tank comprises a stirring tank body, a motor located at the top of the stirring tank body, and a stirring shaft connected to the output end of the motor, wherein the stirring shaft is provided with stirring blades.

[0013] The dosing device comprises a plurality of dosing barrels for containing different medicines, and the dosing barrels are connected with the coagulation and sedimentation device through pipelines.

[0014] The sludge discharge device comprises a sludge pool and a sludge lifting pump connected to the sludge discharge port of the sludge pool through a pipeline.

[0015] The beneficial effects of the present invention are as follows: the present invention uses an ozone flotation device, an electro-Fenton oxidation device and a coagulation sedimentation device to sequentially treat high-difficulty phosphorus wastewater, thereby reducing elemental phosphorus from 30 mg / l to below 0.15 mg / l, and the treated wastewater is reused in production. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the present invention;

[0017] Figure 2 It is a schematic diagram of the structure of the ozone flotation tank of the present invention;

[0018] Figure 3 It is a structural schematic diagram of a stirring tank of the present invention;

[0019] Figure 4 is a process flow chart of the present invention;

[0020] In the figure: regulating tank 1, ozone flotation tank 2, ozone gas storage tank 3, DC electrolysis device 4, stirring tank 5, Fenton sedimentation tank 6, intermediate water tank 7, dosing device 8, sludge tank 9, wastewater lifting pump 10, pressure pump 11, filter lifting pump 12, sludge lifting pump 13, tank body 21, support legs 22, slag suction hopper 23, liquid inlet 24, vent valve 25, releaser 26, stirring tank body 51, stirring shaft 52, motor 53, stirring blade 54. DETAILED DESCRIPTION

[0021] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0022] like Figures 1 to 3 As shown, a device for treating inferior phosphorus in the production of inferior sodium wastewater comprises a regulating tank 1 for preliminary cleaning of wastewater, an ozone flotation device 2 connected to the regulating tank 1 through a wastewater lifting pump 10, an electric Fenton oxidation device connected to the ozone flotation device 2 through a pipeline, a coagulation and sedimentation device connected to the electric Fenton oxidation device through a pipeline, a sludge discharge device connected to the electric Fenton oxidation device, the coagulation and sedimentation device and the ozone flotation device through a pipeline, a dosing device 8 for dosing drugs to the coagulation and sedimentation equipment, and a water outlet of the coagulation and sedimentation device is connected to a filter lifting pump 12 to discharge the treated water. The removal of phosphorus in sewage mainly relies on the conversion of hypophosphorus into orthophosphorus through oxidation. Through direct current electrolysis, the chlorine in the sewage is oxidized into hypochlorite, which degrades a large amount of COD. At the same time, the sacrificial anode iron plate generates ferrous iron to react with phosphorus to precipitate. The effluent enters the original Fenton system for secondary phosphorus removal to ensure that the effluent meets the standards. The present invention uses an ozone flotation device, an electric Fenton oxidation device and a coagulation sedimentation device to sequentially treat the high-difficulty hypophosphorus wastewater, so that the elemental phosphorus is reduced from 30 mg / l to below 0.15 mg / l, and the treated wastewater is returned to production.

[0023] The ozone flotation device comprises an ozone flotation tank 2, an ozone gas storage tank 3 connected to the ozone flotation tank 2 through a pipeline for providing ozone to the ozone flotation tank 2, and a pressure pump 11 connected to the ozone gas storage tank 3 and the ozone flotation tank 2 through a pipeline. The ozone flotation tank 2 comprises a tank body 21, a support leg 22 located at the bottom of the tank body 21, and a slag suction hopper 23 located in the tank body 21. The slag discharge port of the slag suction hopper 23 passes through the tank body 21 and is connected to the mud discharge device through a pipeline. A releaser 26, a liquid inlet 24 and a vent valve 25 are provided at the bottom of the tank body 21. The releaser 26 is connected to the ozone gas storage tank 3 through a pipeline. The air inlet of the ozone gas storage tank 3 is connected to the ozone generator for providing ozone to the ozone gas storage tank 3. The ozone gas storage tank 3 is used to provide ozone to the releaser 26. The oxidizing effect of ozone converts hypophosphorus in sewage into orthophosphorus. During its rising process, ozone can adhere to impurity particles and oil in the water and float to the water surface, thereby removing suspended matter and oil.

[0024] The electro-Fenton oxidation device includes a plurality of DC electrolysis devices 4 connected in sequence, the liquid inlet of the DC electrolysis device 4 is connected to the water outlet of the ozone flotation tank 2 through a pipeline, the bottom of the DC electrolysis device 4 is connected to the mud discharge device through a pipeline, and the liquid outlet of the DC electrolysis device 4 is connected to the coagulation sedimentation device through a pipeline. The removal of phosphorus in sewage mainly relies on the electrolytic oxidation of the DC electrolysis device 4 to convert the subphosphorus into orthophosphorus. At the same time, the chlorine in the sewage is oxidized into hypochlorite, degrading a large amount of COD. At the same time, the sacrificial anode iron plate generates ferrous iron and phosphorus reaction precipitation, and the effluent enters the original Fenton system for secondary phosphorus removal to ensure that the effluent meets the standards. The model of the DC electrolysis device 4 is LDJ-15.

[0025] The coagulation sedimentation device comprises a plurality of stirring tanks 5, a Fenton sedimentation tank 6 connected to the plurality of stirring tanks 5 through pipelines, an intermediate water tank 7 connected to the Fenton sedimentation tank 6 through pipelines, and a filter lift pump 12 connected to the drain outlet of the intermediate water tank 7 through pipelines. The stirring tank 5 comprises a stirring tank body 51, a motor 53 located at the top of the stirring tank 51, and a stirring shaft 52 connected to the output end of the motor 53, wherein a stirring blade 54 is provided on the stirring shaft 52. The stirring blade 54 facilitates the full mixing of the medicine with the sewage to be treated after the medicine is added to the stirring tank 5, thereby improving the efficiency of sewage treatment.

[0026] The dosing device 8 includes a plurality of dosing barrels for containing different medicines. The dosing barrels are connected to the stirring tank 5 through pipelines. Different types of medicines are placed in the dosing barrels according to actual needs to treat wastewater.

[0027] The sludge discharge device includes a sludge tank 9 and a sludge lifting pump 13 connected to the sludge discharge port of the sludge tank 9 through a pipeline. The bottom of the DC electrolysis equipment 4 and the bottom of the stirring tank 5 are connected to the sludge tank 9 through pipelines, and the sludge in the sludge tank 9 is discharged through the sludge lifting pump 13.

[0028] A certain DC voltage is applied to the electrodes of the DC electrolysis device 4, so that an electrochemical reaction occurs on the electrodes. Due to the different electrodes used, the electrochemical reaction at the anode is also different. When an inert electrode (such as a platinum electrode, a titanium electrode, a graphite electrode, etc.) is used, O2 or Cl2 is produced at the anode; when a soluble electrode (such as an iron electrode, an aluminum electrode, etc.) is used, corresponding iron metal ions are produced, and then a hydrolysis reaction occurs in water to form a corresponding coagulant. H2 microbubbles are formed by an electrical flotation reaction at the cathode.

[0029] During the electrolysis of wastewater, due to the electrolysis of water and the electrolytic oxidation of organic matter, gas is generated on the surface of the anode and cathode, and precipitates in the form of tiny bubbles. During the rising process, they can adhere to the impurity particles and oil in the water and float to the water surface, thereby removing suspended matter and oil. During electrolysis, not only does the bubble float, but it also has the effects of coagulation, co-precipitation, electrochemical oxidation, and electrochemical reduction. Since the voltage applied between the cathode and the anode is small and the current intensity is not large, the water is in a state of micro-electrolysis between the plates. The micro-electrolysis can produce active substances in the treated water, which has a very strong sterilization effect and can kill a large number of bacteria in the water.

[0030] When using electrolysis technology, the purpose of adjusting the bubble production can be achieved by simply changing the voltage or current density. There is no need to consider the influencing factors of conductivity, and it has certain inherent advantages when used. The electrolysis process can effectively remove suspended matter, floating oil, and dispersed oil; using electrocoagulation or adding flotation agents can also remove dispersed oil and part of dissolved oil. Since the produced water contains a large amount of chloride ions, the anode releases a large amount of chlorine, which can directly achieve the purpose of sterilization.

[0031] After the wastewater is primarily treated in the regulating tank, it is lifted to the ozone flotation tank by the wastewater lifting pump. At the same time, the ozone storage tank provides ozone for the ozone flotation tank to convert the hypophosphorus in the wastewater into orthophosphorus. The ozone floats in the wastewater and can adhere to the impurity particles and oil in the water and float to the water surface, thereby removing the suspended matter and oil. The wastewater treated with ozone enters the DC electrolysis device 4 for electrolytic oxidation to convert the hypophosphorus in the wastewater into orthophosphorus, and generates gas on the surface of the anode and cathode, which precipitates in the form of tiny bubbles. During the rising process, they can adhere to the water. Impurity particles and oil float to the water surface, thereby removing suspended matter and oil. During electrolysis, not only does it have the effect of bubble floating, but it also has the effects of coagulation, co-precipitation, electrochemical oxidation, and electrochemical reduction. The water treated by the DC electrolysis equipment 4 enters the stirring tank 5. According to actual needs, after adding medicine to the stirring tank through the dosing device, stirring is carried out, so that the wastewater enters the sedimentation tank for sedimentation, and then the wastewater is precipitated in the sedimentation tank 6 and enters the intermediate water tank 7 for collection, and finally discharged through the filter lift pump 12 for recycling.

[0032] The present invention adopts an ozone flotation device, an electro-Fenton oxidation device and a chemical coagulation sedimentation device to sequentially treat high-difficulty phosphorus wastewater, so as to reduce the elemental phosphorus from 30 mg / l to below 0.15 mg / l, and the treated wastewater is reused in production.

Claims

1. A device for treating phosphorus in the production of sodium-containing wastewater, characterized in that: It includes a regulating tank for preliminary cleaning of wastewater, an ozone flotation device connected to the regulating tank through a wastewater lifting pump, an electric Fenton oxidation device connected to the ozone flotation device through a pipeline, a coagulation and sedimentation device connected to the electric Fenton oxidation device through a pipeline, a sludge discharge device connected to the electric Fenton oxidation device, the coagulation and sedimentation device and the ozone flotation device through a pipeline, and a dosing device for dosing drugs for the coagulation and sedimentation equipment. The water outlet of the coagulation and sedimentation device is connected to the filter lifting pump to discharge the treated water.

2. The device for treating phosphorus in the production of sodium-rich wastewater according to claim 1, characterized in that: The ozone flotation device comprises an ozone flotation tank, an ozone gas storage tank connected to the ozone flotation tank through a pipeline and used to provide ozone to the ozone flotation tank, and a pressure pump connected to the ozone gas storage tank and the ozone flotation tank through a pipeline.

3. The phosphorus treatment device for producing sodium-rich wastewater according to claim 2, characterized in that: The ozone flotation tank comprises a tank body, legs located at the bottom of the tank body, and a slag suction hopper located in the tank body. The slag discharge port of the slag suction hopper passes through the tank body and is connected to a mud discharge device through a pipeline.

4. The device for treating phosphorus in the production of sodium-rich wastewater according to claim 3, characterized in that: A releaser, a liquid inlet and a vent valve are arranged at the bottom of the pool body, and the releaser is connected with the ozone storage tank through a pipeline.

5. The device for treating phosphorus in the production of sodium-depleted wastewater according to claim 2, characterized in that: The electro-Fenton oxidation device comprises a plurality of DC electrolysis devices connected in sequence, wherein the liquid inlet of the DC electrolysis device is connected to the water outlet of the ozone flotation tank through a pipeline, the bottom of the DC electrolysis device is connected to the mud discharge device through a pipeline, and the liquid outlet of the DC electrolysis device is connected to the coagulation and sedimentation device through a pipeline.

6. The device for treating phosphorus in the production of sodium-rich wastewater according to claim 1, characterized in that: The coagulation and sedimentation device comprises a plurality of stirring tanks, a Fenton sedimentation tank connected to the plurality of stirring tanks through pipelines, an intermediate water tank connected to the Fenton sedimentation tank through pipelines, and a filtering lifting pump connected to the drainage outlet of the intermediate water tank through pipelines.

7. The device for treating phosphorus in the production of sodium-rich wastewater according to claim 6, characterized in that: The stirring tank comprises a stirring tank body, a motor located at the top of the stirring tank body, and a stirring shaft connected to the output end of the motor, wherein the stirring shaft is provided with stirring blades.

8. The device for treating phosphorus in the production of sodium-rich wastewater according to claim 1, characterized in that: The dosing device comprises a plurality of dosing barrels for containing different medicines, and the dosing barrels are connected with the coagulation and sedimentation device through pipelines.

9. The device for treating phosphorus in the production of sodium-rich wastewater according to claim 1, characterized in that: The sludge discharge device comprises a sludge pool and a sludge lifting pump connected to the sludge discharge port of the sludge pool through a pipeline.

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