WO2013156002A1

WO2013156002A1 - Nano catalyst electrolysis flocculation air flotation device

Info

Publication number: WO2013156002A1
Application number: PCT/CN2013/076545
Authority: WO
Inventors: 张世文
Original assignee: 波鹰(厦门)科技有限公司
Priority date: 2012-04-19
Filing date: 2013-05-31
Publication date: 2013-10-24
Also published as: CN102936072A; CN102936072B

Abstract

A nano catalyst electrolysis flocculation air flotation device. Disposed in a shell is a coagulation sedimentation tank, a primary air flotation tank, an electrolysis air flotation tank, and a slag discharging tank. Provided on top of the coagulation sedimentation tank are a water inlet and a mixer. The bottom of the coagulation sedimentation tank is in communication with the primary air flotation tank. A side waste discharging outlet is connected to a waste discharging pipe. Disposed on the side of the primary air flotation tank is a dissolved air release pipe, a waste discharging outlet is connected to a waste discharging pipe, and the upper part inside of the primary air flotation tank is in communication with the electrolysis air flotation tank. The electrolysis air flotation tank is divided into an upper layer and a lower layer by a upper-lower layer divider. An air-liquid separation chamber in the upper layer is disposed with a slag scraping device. An electrolysis groove is disposed between the upper and lower layer; the bottom of the electrolysis groove is fixed to the bottom of the shell; the top of the electrolysis groove is open and flush with the top of the upper-lower layer divider; electrodes are disposed inside of the electrolysis groove, and the space between the anode and cathode of the electrodes forms a water passage. The present invention integrates electrolysis, flocculation sedimentation, and air flotation into one, and is highly automatic, efficient in waste removal, low in operation cost, and easy to operate and maintain.

Description

Nano catalytic electrolysis flocculation air flotation device

Technical field

The invention relates to a nano catalytic electrolysis flocculation air flotation device, in particular to a set The physical treatment method, the physicochemical treatment method and the biochemical treatment method are integrated, and the nano-catalytic electrolytic flocculation air flotation device is provided with a titanium electrode whose surface is covered with a nano-scale noble metal compound coating material with good catalytic properties as an anode.

Background technique

At present, the techniques for controlling lake eutrophication and wastewater can be divided into physical treatment methods. , physical and chemical treatment and biochemical treatment of three major categories. The physical treatment method mainly uses precipitation, filtration, flotation, evaporation and the like to remove impurities of larger particles, etc., wherein flotation is also called The air floatation method is one of the easiest methods of wastewater treatment. Its principle is to try to make a large amount of microbubbles in the water to form a three-phase mixture of water, gas and removed substances, and the buoyancy at the interfacial tension and bubble rise. And the combination of hydrostatic pressure and other forces, promote After the fine bubbles adhere to the removed minute oil droplets and other contaminants, the density of the binder is less than the water and floats to the surface of the water, so that the oil particles and other pollutants in the water are separated and removed. The physicochemical treatment method mainly uses redox, extraction, adsorption, ion exchange, coagulation precipitation, neutralization, electrodialysis and other methods to remove fine suspended solids, colloids and water-soluble substances, or to modify toxic substances into non-toxic substances. The biochemical treatment method mainly separates and removes the colloidal and dissolved organic substances in the wastewater by biological action, mainly including anaerobic Method, aerobic method, anaerobic fermentation method, etc.

In recent years, the electric float method is a more active wastewater treatment technology in the materialized treatment technology. The method is provided with positive and negative electrodes in the water. When the direct current is applied, tiny bubbles are generated on one electrode (cathode), and at the same time, effects such as electrolytic coagulation are generated. Currently, there are various types of electrical float devices that have been used in life. Treatment of sewage, industrial organic wastewater, electroplating wastewater, oil field wastewater, etc. However, the existing electrical float method The device exposes some problems during the operation. First, the electrode consumes a large amount, and the electrode material pollutes the water body. Second, the electrode has a small electric density, a high overpotential, and a high working voltage. The amount of strong oxidizing substances and microbubbles in the initial ecology is limited, the efficiency of electric energy application is not high, and the energy consumption is large. Third, after electrolysis, the solid-liquid separation effect is not satisfactory, and secondary solid-liquid separation is required, and the treatment process is long.

China Patent: 201010202356 . 5 discloses a grading and recycling device for electroflocculation-electric float cleaning bath and laundry wastewater, which is characterized in that the effluent of the sump is directly outputted through the three-way one-way as the front-end effluent, and the other is connected in series to the venturi. Tube, the outlet of the venturi tube is connected to the electrolysis tank, and the throat of the venturi tube is connected with the inlet pipe with the filter cover; the electrolyzer is set as the iron-assisted double anodization unit, which is a Ti/SnO ₂ anode and a Fe anode. A combined anode is formed on both sides of the cathode, and an air diffusion electrode is used in the cathode; a two-stage filtration unit is arranged in series at the outlet of the electrolytic tank, and a first-stage outlet valve is arranged on the primary filtration chamber of the two-stage filtration unit; A secondary outlet valve is arranged on the secondary filtration chamber of the unit; the surfactant and other organic pollutants in the bath/washing wastewater can be effectively reduced or removed, so that the bath/washing wastewater is fractionated and reused.

Chinese patent CN02248009.9 discloses a device for treating sewage by electric float method, The electric float reactor consists of a number of tubular reaction units consisting of a cathode rod, a short tube, an insulating sleeve, an anode outer tube and an insulating pin. The anode outer tube and the cathode rod are coaxially mounted, and the annular gap between the two poles constitutes a sewage passage, and the short tube attached to the other end of the cathode rod and the cathode rod together form a cathode, and the plurality of reaction units are connected in series and horizontally installed in the apparatus body. The units are connected by metal conductive strips, which solves the problems of small water collection ratio, poor mass transfer conditions, uneven current distribution, and low processing capacity per unit volume of the existing sewage treatment equipment, and has a simple structure and is advantageous for enhancing mass transfer. It can shorten the treatment time and improve the efficiency of sewage treatment. It is widely suitable for industrial wastewater treatment, industrial circulating cooling water treatment and domestic water treatment.

technical problem

The invention aims at the deficiencies of the existing electric floating device, and provides a gas collecting and floating technology, a flocculation and sedimentation technology, a nanotechnology, an electrocatalytic technology and an electrochemical technology, and has a good catalytic property with a nanometer surface covering the surface. The titanium electrode of the precious metal compound coating material is an anode, and the nano catalytic electrolysis flocculation air flotation device integrating electrolysis, solid-liquid separation and gas-liquid separation functions is integrated. The invention adopts two-stage air flotation treatment, and the first stage adopts physical air floatation, so that the pollutant adheres to the bubble, so that the density is less than water, thereby achieving suspension separation; the second stage is to adopt nanometer collection on the basis of physical air floatation. Electrochemical methods combining technology and catalytic technology are used for secondary air flotation treatment. Compared with the traditional electrolysis device, the invention has the characteristics of extremely low operating voltage, large current density, low energy consumption, high electric efficiency, no electrode consumption, and integrates various functions such as electrolysis, flocculation and sedimentation, and air flotation. .

Technical solution

The invention is provided with a shell, and the shell is divided into four functional pools, such as a coagulation sedimentation tank, a first-stage air floating pool, an electrolysis air floating tank and a slag discharge tank, by a partition plate. The top of the coagulation mixing tank is provided with a water inlet and a stirrer, and the water inlet is connected to the waste water inlet pipe through a pipeline, and a waste water outlet is arranged at the bottom of the coagulation sedimentation tank, the waste water outlet and the first gas The floating pool is connected. The bottom of the first-stage air floating pool is provided with a dissolved gas release device and a dissolved gas release pipe, and the dissolved gas release pipe is connected with the dissolved gas release device and the air compressor pipe, and the top of the first-stage air floating pool is connected with the electrolytic air floating pool. The bottom and the upper part of the electrolysis air floating pool are separated by a baffle, and are divided into upper and lower layers, the upper layer is a gas-liquid separation chamber, and a scraping device is arranged, the slag outlet is connected with the slag discharge tank, and the lower layer is a drainage sedimentation chamber. There is an electrolytic cell between the upper and lower layers, and at least one electrolytic cell is arranged. The bottom of the electrolytic cell is fixed at the bottom of the inner casing. The top of the electrolytic cell is open and horizontal with the top of the upper and lower baffles. The electrode is equipped with electrodes, and the electrode includes an anode and The cathode, the spacing between the anode and the cathode is a water passage. The anode is coupled to the anode of the direct current power source, the cathode is coupled to the cathode of the direct current power source; the drain outlet is disposed at the bottom of the drainage sedimentation chamber, and the water collection outlet pipe is disposed at an upper position in the middle of the drainage sedimentation chamber, and is connected to the electrolysis water outlet conduit. The slag discharge tank is provided with a slag discharge port, and the slag discharge port is connected with the slag discharge pipe.

The casing is provided with an inner layer and an outer layer, the inner layer is treated with an epoxy asphalt paint, and the outer layer is an outer layer of steel.

The electrolysis floating tank is divided into a drainage sedimentation chamber and a gas-liquid separation chamber.

The electrolytic cell is a rectangular parallelepiped electrolytic cell or a rectangular parallelepiped electrolytic cell.

An electrode is installed in the electrolytic cell, the electrode includes an anode and a cathode, and the spacing between the anode and the cathode is 2 mm ~ 4mm, the gap between the anode and the cathode acts as a water flow channel.

A gap of 150 mm to 200 mm in height is left between the anode and the top of the cathode and the top of the electrolytic cell in the electrolytic cell.

The anode is a titanium substrate anode covered with a metal oxide coating having a crystal grain size of 10 to 35 nm, and the anode is in a shape of a flat plate, an arc shape, a cylinder shape, or a mesh shape; The cathode is made of titanium, iron, aluminum, stainless steel, zinc, copper, nickel, lead or graphite, and the cathode has one of a flat shape, an arc shape, a cylindrical shape, and a mesh shape.

The working voltage between the anode and the cathode is 2 to 8 V, the current density is 10 to 250 mA/cm ² , the working voltage between the anode and the cathode is preferably 3 to 5 V, and the optimum current density is 100 to 150 mA/cm ² .

The flocculating agent added to the coagulation sedimentation tank is a combination of one or more of an aluminum salt, an iron salt, a poly aluminum, and a poly iron, and the amount is 2 to 500 g/m ³ ; the coagulant; It is a polyacrylamide and is added in an amount of 2 to 300 g/m ³ .

When treating fresh water, sea water and brackish water, wastewater, municipal sewage, firstly add a proper amount of flocculant and coagulant under stirring by means of a coagulation sedimentation tank in the plant to accelerate solid particulate matter in water (such as chemistry). The precipitates, the flocs formed by the coagulation treatment, the biologically treated sludge, etc.) agglomerate each other to form a particulate solid having a large particle size and mass, and are quickly precipitated and removed from the water, and at the same time, the water is removed by precipitation. Sand; then, into the first-stage air-floating tank, the tiny bubbles generated by the dissolved gas release device adhere to a large amount of light suspended matter (such as fine solid particles, oil, benzene, etc.) in the water to reach the effect of solid-liquid separation or liquid-liquid separation. , thereby reducing COD, ammonia nitrogen, chromaticity, turbidity, etc. in the water; the effluent of the primary air floatation tank enters the electrolysis air floatation tank, and the strong oxidizing substance produced by electrolysis kills microorganisms, bacteria, algae and plankton in the water, and oxidatively decomposes The organic matter in the water greatly reduces the COD, color, turbidity, ammonia nitrogen, odor and other pollution indicators in the water; finally collects the sediment through the slag pool Scum, so that the water purification obtained.

The electrolyzed air floating tank reduces the overpotential of the electrolysis by the electrocatalysis of the nano-coating covering the surface layer of the anode during the disinfection and purification of the fresh water, so that the fresh water is electrolyzed to generate a radical at a lower voltage condition, as initially Ecological oxygen, nascent chlorine, hydroxyl and hydrogen, and the following four effects:

1. The free radicals generated by electrolysis, such as nascent oxygen, nascent chlorine, hydroxyl and other strong oxidizing substances can kill microorganisms, bacteria, algae and plankton in the water, and the resulting corpses can be removed by a large number of tiny bubbles generated by the cathode. Eliminate pollution from microorganisms, algae and plankton and reduce turbidity;

2. The strong oxidizing substance produced by electrolysis can oxidize and decompose organic matter in water, and reduce the pollution index such as COD, chromaticity and odor in water;

3. Under the action of electric field, on the one hand, the suspended solids, colloids, charged particles and other substances in the water are destabilized. On the other hand, the cations and anions in the water move to the cathode and the anode respectively, and the electric double layer acts on the cathode and the anode. The action of the electric layer forms a precipitation-induced flocculation effect, which promotes the formation of coarse flocs by fine suspended matter, colloids, charged particles and the like, accelerates the sedimentation of impurities, and effectively reduces the pollution indexes such as SS and turbidity;

4. A large amount of nascent hydrogen produced by the cathode during electrolysis can form small bubbles of hydrogen gas, which has an air floating effect. As the bubbles rise, a large amount of light suspended matter will adhere to the solid-liquid separation or liquid-liquid separation. Thereby further reducing COD, chromaticity, turbidity and the like in water.

When the electrolyzed air floatation tank is used for purifying and disinfecting seawater and brackish water, the electrocatalytic action of the coating covering the surface layer of the anode is used to reduce the overpotential of the electrolysis, thereby causing the seawater and brackish water after the first air flotation. Electrolysis at lower voltages produces nascent chlorine [Cl] and nascent hydrogen [H], and the following four effects occur:

1. The nascent chlorine [Cl] produced by electrolysis has strong oxidizing properties, which can kill microorganisms, algae and plankton in the water. The resulting corpses can be removed and removed together with a large number of tiny bubbles generated by the cathode, completely eliminating microorganisms, algae and Plankton contamination and reduced turbidity;

2. The nascent chlorine [Cl] produced by electrolysis can oxidize and decompose organic matter in water, and reduce the COD, chroma, odor and other pollution indicators in the water;

When the electrolysis floating tank is treated with waste water and municipal sewage, the electrocatalytic action of the coating covering the surface layer of the anode is used to reduce the overpotential of the electrolysis, so that the wastewater after the first air flotation and the municipal sewage are lower. Electrolysis under voltage conditions, producing nascent strong oxidizing substances, in the presence of a large amount of chloride ions, the production of nascent chlorine [Cl] and nascent hydrogen [H]; in the absence of chloride ions, It is the nascent oxygen [O], hydroxyl [OH] and nascent hydrogen [H], and the following seven effects occur:

1. Electrolytic priming strong oxidizing substances kill microorganisms, bacteria, algae and plankton in water and combine with a large number of tiny bubbles generated by the cathode to remove and eliminate the pollution of microorganisms, bacteria, algae and plankton and reduce turbidity. degree;

2. The eutectic strong oxidizing substances produced by electrolysis rapidly oxidize and decompose the organic matter in the wastewater, so that the macromolecular substances are decomposed into small molecular substances, reduce the COD in the wastewater, increase the B/C value, and improve the biodegradability. Processing to create better biochemical conditions;

3. The eutectic strong oxidizing substance produced by electrolysis rapidly oxidizes and decomposes the chromophoric group and the color-promoting group remaining in the waste water, causing chain scission or ring opening, decolorizing the wastewater, and combining with the cathode. The air flotation of a large number of tiny bubbles effectively reduces the color of the wastewater and achieves the purpose of decolorization;

4. The eutectic strong oxidizing substance produced by electrolysis rapidly oxidizes and decomposes ammonia nitrogen in wastewater, and reduces ammonia nitrogen index in water;

5. Various free radicals (strong oxidizing substances) produced by electrolysis can oxidize and decompose the odorous groups in the wastewater to remove the foul odor in the wastewater;

6. Under the action of electric field, on the one hand, the suspended solids, colloids, charged particles and other substances in the water are destabilized. On the other hand, the cations and anions in the water move to the cathode and the anode respectively, and the electric double layer acts on the cathode and the anode. The action of the electric layer forms a precipitation-induced flocculation effect, which promotes the formation of coarse flocs by fine suspended matter, colloids, charged particles and the like, accelerates the sedimentation of impurities, and effectively reduces the pollution indexes such as SS and turbidity;

7. A large amount of nascent hydrogen produced by the cathode during electrolysis can form small bubbles of hydrogen gas, which has the effect of air flotation. As the bubbles rise, a large amount of light suspended matter will adhere to the solid-liquid separation or liquid-liquid separation. Thereby further reducing COD, chromaticity, turbidity and the like in water.

In summary, the present invention is a novel water treatment device integrating gas floating technology, flocculation sedimentation technology, nanotechnology, catalytic technology and electrochemical technology, which integrates various functions such as electrolysis, flocculation sedimentation and air flotation, and can be fast, Effectively reduce COD, ammonia nitrogen, color, odor, turbidity, SS, etc. in water, and kill microorganisms, bacteria, algae and plankton in water, so that the water body can be purified.

Beneficial effect

The use of nano-catalytic electrolysis flocculation flotation devices for the purification of water has the following significant advantages:

1, it It integrates various functions such as electrolysis, flocculation and sedimentation, air flotation, etc., with high degree of automation, high decontamination efficiency, low operating cost, and convenient operation and maintenance;

2. The addition of chemical substances such as flocculants and air floatants is only one-fifth of the traditional process, which not only greatly reduces the consumption of chemical substances, saves water treatment costs, but also reduces secondary pollution;

3. The amount of sludge produced is only one-fifth of that of traditional technology, which greatly reduces sludge discharge and reduces the cost of solid waste treatment;

4, the device is stable, can quickly and effectively treat bacteria, algae, microorganisms, zooplankton, COD, ammonia nitrogen, color, odor, turbidity, SS, etc. in water, the effluent water quality is good.

DRAWINGS

FIG. 1 is a schematic structural view of an embodiment of the present invention.

Figure 2 is a top view of Figure 1.

Figure 3 is a side view of Figure 1.

BEST MODE FOR CARRYING OUT THE INVENTION

The invention will be further described below with reference to the accompanying drawings:

As shown in FIGS. 1 to 3, the embodiment of the present invention is provided with a housing 1 , coagulation sedimentation tank 2, first-stage air flotation tank 3, electrolysis gas floatation tank 4, slag discharge tank 5, water inlet 6, agitator 7 , dissolved gas release pipe 8, electrolytic cell 9, electrode 10, scraping device 11. Slag discharge port 12, drain outlet 13, upper and lower baffles 14, water collecting pipe 15, sewage outlet 16, drainage sedimentation chamber 17, gas-liquid separation chamber 18, water collection outlet 19, dissolved gas release 20, anode wiring Column 21 and cathode terminal 22 .

Separated into a coagulation sedimentation tank by a partition in the casing 1 2. a primary air floatation tank 3, an electrolysis air floatation tank 4, a slag discharge tank 5 Four pools, coagulation sedimentation tank 2 with water inlet 6 at the top and agitator 7, water inlet 6 connected to the wastewater inlet pipe through the pipeline, the bottom of the coagulation sedimentation tank is connected with the first-stage air-floating tank 3, and the side sewage outlet 16 Connected to the sewage pipe; the first air flotation tank 3 is provided with a dissolved gas release pipe 8, the dissolved gas release pipe 8 is connected with the dissolved gas release device 20, the external gas source, and the sewage outlet 16 is connected with the sewage pipe, in the first-stage air floating pool 3 The inner upper portion communicates with the electrolysis air floating tank 4; the electrolysis air floating tank 4 is divided into upper and lower layers by the partition plate 14, and the upper layer is a gas-liquid separation chamber. There is a scum scraper and a slag outlet, and an electrolytic tank is arranged between the upper and lower layers, and at least one electrolytic tank 9 is provided. The bottom of the electrolytic tank 9 is fixed at the bottom of the casing 1, and the top of the electrolytic tank 9 is open and Upper and lower partitions 14 At the top level, an electrode 10 is mounted in the electrolytic cell 9, the electrode 10 includes an anode and a cathode, and a gap between the anode and the cathode is a water passage, and the anode passes through the anode terminal 21 Connected to the anode of the direct current power source, the cathode is coupled to the cathode of the direct current power source through the cathode terminal 22, the drain outlet 16 is disposed at the bottom of the drainage sedimentation chamber 17, and the water collection tube 15 is disposed in the drainage sedimentation chamber. The middle upper position is connected with the electrolysis water outlet pipe; the slag discharge tank 5 is provided with a slag discharge port 12, and the slag discharge port 12 is connected with the slag discharge pipe.

The casing 1 is composed of inner and outer layers, the inner layer is treated with epoxy asphalt paint, and the outer layer is steel plate.

An electrode 10 is mounted in the electrolytic cell 9, the electrode 10 includes an anode and a cathode, and the spacing between the anode and the cathode is 2 mm to 4 mm. .

A gap of 150 mm to 200 mm is left between the anode and the top of the cathode and the top of the electrolytic cell 9 in the electrolytic cell 9.

The anode is made of titanium as a substrate, and the surface is covered with crystal grains of 10 to 35 nm. An inert anode of a metal oxide coating, the anode being in the shape of a flat plate, an arc, a cylinder, or a mesh; the cathode is titanium, iron, aluminum, stainless steel, zinc, copper, nickel, Lead or graphite is a cathode of the material, and the cathode has one of an arc shape, a cylindrical shape, and a mesh shape.

9 in the operating voltage between the anode and the cathode when the electrolytic cell flotation apparatus nanocatalytic electrocoagulation work 2 ~ 8V, a current density of 10 ~ 250mA / cm ^2; optimum operating voltage between the two electrodes is 3 ~ 5V, the most The current density is 100 to 150 mA/cm ² .

When treating fresh water, sea water, brackish water, wastewater and municipal sewage, firstly add 2 to 500 g/m ³ of flocculant and 2 to 300 g/m ^{3 of} aid through the coagulation sedimentation tank in the apparatus. The coagulant accelerates the solid particles in the water (such as chemical precipitates, flocs formed by coagulation treatment and biologically treated sludge, etc.) to agglomerate each other to form particulate solids with large particle size and mass, and quickly precipitates. Removed from the water, and at the same time removes the sand particles in the water by precipitation; then, enters the first-stage air floating pool, and the tiny bubbles generated by the dissolved gas release device adhere to a large amount of light suspended matter (such as fine solid particles, oil, benzene, etc.) in the water. To achieve the effect of solid-liquid separation or liquid-liquid separation, thereby reducing COD, ammonia nitrogen, color, turbidity, etc. in the water; the effluent from the primary air-floating tank enters the electrolysis air-floating tank, and the strong oxidizing substance generated by electrolysis kills microorganisms in the water , bacteria, algae and plankton, and oxidative decomposition of organic matter in water, so that the COD, color, turbidity, ammonia nitrogen, odor and other pollution indicators in the water are greatly reduced; The precipitate was collected and scum, so that the water purification obtained.

Embodiments of the invention

Example 1

Treatment effect on eutrophic lake water

The lake is pumped into the nano-catalytic electrolytic flocculation air flotation device, and the flocculant PAC is added in the coagulation sedimentation tank 2 at 20-500 g/m ³ , and the agitator 7 is used for stirring to accelerate the precipitation; at the same time, the first-stage air-floating tank 3 is opened. Dissolving the gas release device 20 and adjusting an appropriate gas flow rate; the voltage between the two electrodes of the electrolysis cell 9 in the electrolysis floating cell 4 is 3 to 8 V, and the current density is 10 to 150 mA/cm ² , and the lake water is maintained in the first-stage air floating cell 3 The residence time in the medium is 1 to 2 minutes, and the residence time between the plates of the electrolytic cell 9 is 0.3 to 1 minute. The effects before and after the treatment are shown in Table 1.

Table 1 Treatment effect of eutrophic lake water purification

序号Serial number		COD_Cr （ mg/L ） COD _Cr ( mg/L )	氨氮（mg/L） Ammonia nitrogen (mg/L)	SS （mg/L） SS (mg/L)	浊度（NTU） Turbidity (NTU)	pH值pH value	细菌总数（个/L）Total number of bacteria (pieces / L)	藻类（个/L） Algae (/L)
11	进水 Influent	99	0.50.5	1515	44	7.237.23	5.4×10⁵ 5.4×10 ⁵	4.5×10⁸ 4.5×10 ⁸
22	一级气浮后After the first level of air flotation	66	0.50.5	1010	44	7.237.23	4×10⁴ 4×10 ⁴	4.5×10⁵ 4.5×10 ⁵
33	出水Water	00	未检出not detected	11	11	6.96.9	≤40≤40	1.8×10² 1.8×10 ²

Example 2

Treatment effect on seawater

The seawater is pumped into the nano-catalytic electrolysis flocculation air flotation device, and 2 to 100 g/m ^{3 of} flocculant PAC is added to the coagulation sedimentation tank 2, and the agitator 7 is used for stirring to accelerate the precipitation; and at the same time, the first-stage air-floating tank 3 is opened. Dissolving the gas release device 20 and adjusting an appropriate gas flow rate; the voltage between the two electrodes of the electrolysis cell 9 in the electrolysis floating cell 4 is 3 to 5 V, and the current density is 10 to 200 mA/cm ² , and the seawater is maintained in the first-stage air floating cell 3 The residence time in the medium is 1 to 2 minutes, and the residence time between the plates of the electrolytic cell 9 is 0.3 to 1 minute. The effects before and after the treatment are shown in Table 2.

Table 2 Treatment effect on seawater purification

序号Serial number		COD_Cr （ mg/L ） COD _Cr ( mg/L )	氨氮（mg/L） Ammonia nitrogen (mg/L)	SS （mg/L） SS (mg/L)	浊度（NTU） Turbidity (NTU)	pH值pH value	细菌总数（个/L）Total number of bacteria (pieces / L)	藻类（个/L） Algae (/L)
11	进水 Influent	77	0.30.3	1919	3.53.5	8.68.6	2.4×10³ 2.4×10 ³	2.5×10⁴ 2.5×10 ⁴
22	一级气浮后After the first level of air flotation	66	0.30.3	1717	3.23.2	8.68.6	1.4×10³ 1.4×10 ³	2.5×10³ 2.5×10 ³
33	出水Water	00	未检出not detected	11	11	7.27.2	≤3≤3	未检出not detected

Example 3

Treatment effect on wastewater treated by printing and dyeing

The biochemical treatment of the secondary sedimentation tank printing and dyeing advanced treatment wastewater is pumped into the nano catalytic electrolysis flocculation air flotation device, the flocculant PAC is added to the coagulation sedimentation tank 2, 800g of PAC is added per ton of wastewater, and the agitator 7 is used for stirring and accelerating Precipitation; simultaneously open the dissolved gas release unit 20 in the primary air floating tank 3, and adjust the appropriate gas flow rate; the voltage between the two poles of the electrolytic cell 9 in the electrolytic air floating tank 4 is 3 to 5 V, and the current density is 10 to 250 mA/cm ² In the state, the residence time of the wastewater in the primary flotation cell 3 is 5 to 10 minutes, and the residence time between the plates of the electrolytic cell 9 is 2 to 5 minutes, and the effects before and after the treatment are shown in Table 3.

Table 3: Treatment effect of advanced dyeing wastewater treatment

序号Serial number		COD_Cr （ mg/L ） COD _Cr ( mg/L )	氨氮（mg/L） Ammonia nitrogen (mg/L)	SS （mg/L） SS (mg/L)	色度（倍）Chromaticity (times)	pH值 pH value
11	进水Influent	316316	3.93.9	9090	200200	7.37.3
22	一级气浮后After the first level of air flotation	201201	4.04.0	8181	185185	7.67.6
33	出水Water	153153	未检出not detected	123123	7575	6.96.9

Example 4

Treatment effect on tannery wastewater

The tannery wastewater enters the coarse grid filter to remove large particles of solids and then flows into the conditioning tank for mixing. The wastewater from the conditioning tank is pumped into the hydraulic screen to remove impurities such as hair and then flows into the desulfurization reaction tank. The desulfurized wastewater flows into the nano catalytic electrolysis flocculation gas. Floating, adding flocculant FeSO _{4 to the} coagulation sedimentation tank 2, adding 800 g of FeSO ₄ per ton of waste water, stirring with a stirrer 7 to accelerate the precipitation; simultaneously opening the dissolved gas release device 20 in the first-stage air floating tank 3, and Adjusting the appropriate gas flow rate; the voltage between the two electrodes of the electrolysis cell 9 in the electrolysis floating cell 4 is 3 to 5 V, and the current density is 10 to 250 mA/cm ² , and the residence time of the wastewater in the first-stage air floating cell 3 is 5~ 15 , and the residence time between the plates of the electrolytic cell 9 is 2 to 5 minutes, and the effects before and after the treatment are shown in Table 3.

Table 4 treatment effect of tannery wastewater

序号Serial number		COD_Cr （ mg/L ） COD _Cr ( mg/L )	氨氮（mg/L） Ammonia nitrogen (mg/L)	SS （mg/L） SS (mg/L)	色度（倍）Chromaticity (times)	pH值 pH value
11	进水Influent	164164	12.312.3	22twenty two	120120	8.98.9
22	一级气浮后After the first level of air flotation	134134	1212	2020	111111	8.58.5
33	出水Water	7575	未检出not detected	1212	88	8.38.3

Industrial applicability

The invention integrates various functions such as electrolysis, flocculation and sedimentation, air flotation, etc., has high automation degree, high decontamination efficiency, low running cost, convenient operation and maintenance With good industrial applicability.

Claims

The invention relates to a nano catalytic electrolysis flocculation air flotation device, which is characterized in that a casing is arranged, and four tanks of a coagulation sedimentation tank, a first-stage air flotation tank, an electrolysis air flotation tank and a slag discharge tank are arranged in the shell, and the top of the coagulation sedimentation tank is provided. There is a water inlet and a stirrer, the water inlet is connected with the waste water inlet pipe through a pipeline, the bottom of the coagulation sedimentation tank is connected with the first-stage air floating pool, the side sewage outlet is connected with the sewage pipe; and the dissolved gas is provided at the edge of the first-stage air floating pool. The release tube, the dissolved gas release tube is connected with the dissolved gas release device and the external gas source, and the sewage outlet is connected with the sewage discharge pipe, and the inner upper portion of the first-stage air floating pool is connected with the electrolytic air floating pool; the electrolytic air floating pool is divided into upper and lower layers by the upper and lower partition plates. The upper gas-liquid separation chamber is provided with a scraping device, and an electrolytic cell is arranged between the upper and lower layers, and at least one electrolytic cell is provided. The bottom of the electrolytic cell is fixed at the bottom of the inner casing, and the top of the electrolytic cell is open and top of the upper and lower partition plates Horizontally, an electrode is installed in the electrolytic cell, the electrode includes an anode and a cathode, and a distance between the anode and the cathode is a water passage, and the anode is connected to an anode of a direct current power source through an anode terminal, and the cathode is connected The cathode connection post is connected with the cathode of the DC power source, the sewage outlet is arranged at the bottom of the drainage sedimentation chamber, and the water collection pipe is arranged at an upper position in the middle of the drainage sedimentation chamber, and is connected with the electrolysis water outlet pipe; the slag discharge tank is provided with a slag discharge port and a slag discharge port Connected to the slag discharge pipe.
Claims 1 The nano-catalytic electrolytic flocculation air flotation device is characterized in that the shell is composed of inner and outer layers, the inner layer is treated with epoxy asphalt paint, and the outer layer is steel plate.
Claims 1 The nano catalytic electrolysis flocculation air flotation device is characterized in that an electrode is installed in the electrolytic cell, the electrode comprises an anode and a cathode, and the spacing between the anode and the cathode is 2 mm to 4 mm. A gap of 150 mm to 200 mm is left between the anode and the top of the cathode and the top of the electrolytic cell in the electrolytic cell.
A nano-catalytic electrolytic flocculation air flotation device according to claim 1, wherein the anode is made of titanium as a substrate, and the surface is covered with crystal grains of 10 to 35 nm. The metal oxide coating has a stable anode, and the anode has a shape of a flat plate, an arc shape, a cylindrical shape, and a mesh shape; the cathode is titanium, iron, aluminum, stainless steel, zinc, copper, nickel The lead or graphite is a cathode of the material, and the cathode has one of a flat shape, an arc shape, a cylindrical shape, and a mesh shape.
A nano-catalytic electrolytic flocculation air flotation device according to claim 1, wherein the working voltage of the anode and the cathode in the electrolytic cell is 2~8V and the current density is 10 when the nano-catalytic electrolytic flocculation air flotation device is operated. ~250mA/cm 2 .
The nano-catalytic electrolytic flocculation air flotation device according to claim 1, wherein the optimal working voltage between the two electrodes in the electrolytic cell when the nano-catalytic electrolytic flocculation air flotation device is operated is 3 to 5 V, and the optimal current density is It is 100 to 150 mA/cm 2 .