CN217103192U

CN217103192U - Electric flocculation device

Info

Publication number: CN217103192U
Application number: CN202122694777.0U
Authority: CN
Inventors: 李猛; 莫测辉; 于朋飞; 严剑芳
Original assignee: Jinan University
Current assignee: Jinan University
Priority date: 2021-11-04
Filing date: 2021-11-04
Publication date: 2022-08-02
Anticipated expiration: 2031-11-04

Abstract

The utility model relates to an electric flocculation device. The electric flocculation device comprises an electrolytic bath, a plurality of groups of anodes and a plurality of groups of cathodes; the anodes and the cathodes are arranged in the electrolytic cell in parallel at intervals, and the anode at the outermost side and the cathode at the outermost side are respectively connected with an external power supply; the adjacent cathodes and anodes at the middle side are connected in series in pairs. The utility model provides an electric flocculation device is as the electrode with the positive pole and the negative pole of interval parallel arrangement and specific connection to the cooperation utilizes electrolyte can realize perfluor organic pollutant's high-efficient degradation, and easy operation has advantages such as flocculating constituent is small, degradation process is simple high-efficient, the power consumption is less, the degradation is stable.

Description

Electric flocculation device

Technical Field

The utility model belongs to the technical field of waste water treatment, concretely relates to electric flocculation device.

Background

Perfluorinated organic pollutants (perfluorooctanoic acid and perfluorooctane sulfonic acid) are widely used in the fields of lubricating oil, fire-fighting foam, raincoats, food packaging, medical equipment and the like because of their high stability. However, with the heavy use of this organic pollutant, its bioaccumulation, environmental resistance and potential toxicity of different organisms as well as hepatotoxicity and immunotoxicity are also receiving great attention. Due to its great threat to humans, the stockholm convention of stego, 2009, has placed on a list of persistent organic pollutants and has been called upon to restrict use worldwide. However, some of the existing conventional technologies (adsorption, ultrasonic irradiation, reverse osmosis and photocatalysis) have some limitations such as high energy consumption, limited treatment conditions or high cost, which make the removal of perfluorinated organic pollutants challenging.

In recent years, the electrocoagulation technology has remarkable potential in effectively removing organic pollutant wastewater containing oil, dye, surfactant and the like. The metal hydroxide flocs formed in situ can strongly adsorb these contaminants and remove them from the contaminated water by electrochemical oxidation of the sacrificial anode. Although the electric flocculation technology can effectively remove perfluorinated organic pollutants from wastewater, the floccule generated in the electric flocculation process can only transfer the organic pollutants from the water, and can not effectively degrade the organic pollutants, thereby still bringing great threat to the environment. Therefore, it is important to find a technology for degrading perfluorinated organic pollutants effectively and stably.

Patent CN104261519A discloses a method for removing perfluorinated organic pollutants in wastewater, which discloses a specific constant current flocculation device, utilizes a hydrogen peroxide coupling electric flocculation method to realize effective degradation of perfluorinated organic matters, but the hydrogen peroxide is required to be fed at intervals, and gelatin powder is required to be added after electric flocculation to realize thorough removal of perfluorinated pollutants, so that the operation is complex.

Therefore, the design of a novel electric flocculation device for realizing simple and efficient removal of the perfluorinated organic pollutants has important research significance and application value.

Disclosure of Invention

The utility model aims to overcome the defect of complex operation of the prior electric flocculation device when treating perfluorinated pollutants, and provides an electric flocculation device. The utility model provides an electric flocculation device uses interval parallel arrangement's positive pole and negative pole as the electrode to the high-efficient degradation of perfluor organic pollutant can be realized to the cooperation utilizing the electrolyte, and easy operation has advantages such as flocculating constituent is small, degradation process is simple high-efficient, the power consumption is less, the degradation is stable.

In order to realize the purpose of the utility model, the utility model adopts the following technical scheme:

an electric flocculation device comprises an electrolytic bath, a plurality of groups of anodes and a plurality of groups of cathodes; the anodes and the cathodes are arranged in the electrolytic cell in parallel at intervals, and the anode at the outermost side and the cathode at the outermost side are respectively connected with an external power supply; the adjacent cathodes and anodes at the middle side are connected in series in pairs.

The electric flocculation device provided by the utility model has simple structure, the cathodes and the anodes are designed in parallel at intervals, the cathodes and the anodes at the outer sides are connected with a power supply, and the cathodes and the anodes at the middle sides are connected in series in pairs; can make electrode and electrolyte fully contact through this modified electrode configuration, and every plate electrode has similar current distribution, can promote electrochemical reaction and accelerate the degradation of organic matter, this configuration is on the basis of using perfluor organic pollutant solution and the mixture of sodium chloride and persulfate mixed solution as electrolyte, and the coupling uses persulfate as the activation medium, can realize high-efficient degradation perfluor organic pollutant through electric flocculation, has advantages such as flocculating constituent small, degradation process is simple high-efficient, the power consumption is less, the degradation is stable.

Preferably, the top of the electrolytic cell is provided with an opening.

The material, the spacing and the size of the anode and the cathode can be selected according to actual requirements.

Preferably, the anode is an iron plate electrode or an aluminum plate electrode.

Preferably, the cathode is an iron plate electrode or an aluminum plate electrode.

Preferably, the distance between the adjacent anode and cathode is 1.5-2 cm. Under the condition, the electric flocculation effect can be further improved by matching with the interval design.

Preferably, the size of the anode is (2.0-3.0) cm x (2.0-3.0) cm.

Preferably, the size of the cathode is (2.0-3.0) cm x (2.0-3.0) cm.

Preferably, the anode and the cathode are in 2-5 groups.

Preferably, the electrolytic cell is provided with an electrolyte.

More preferably, the electrolyte is a mixed solution of perfluorinated organic pollutants, electrolytes and persulfates.

Further preferably, the electrolyte concentration in the electrolyte is 0.07-0.1 mol/L.

Further preferably, the electrolyte is one or more of sodium chloride, potassium chloride or sodium sulfate.

Further preferably, the concentration of the persulfate in the electrolyte is 50-75 mg/L.

Further preferably, the persulfate is one or more of peroxymonosulfate or peroxydisulfate, such as sodium peroxymonosulfate, sodium peroxydisulfate, and the like.

Further preferably, the concentration of the perfluorinated organic pollutant solution in the electrolyte is 5-10 mg/L.

Further preferably, the perfluorinated organic pollutant is one or more of perfluorooctanoic acid or perfluorooctane sulfonic acid.

Preferably, the power supply is a dc power supply.

Preferably, the voltage of the direct current power supply is 55-75V.

Preferably, the current density is 6-18 mA/cm ² 。

Compared with the prior art, the utility model discloses following beneficial effect has:

the utility model provides an electric flocculation device regards as the electrode with the positive pole and the negative pole of interval parallel arrangement and specific connection to the cooperation utilizes the electrolyte can realize perfluor organic pollutant's high-efficient degradation, and easy operation has advantages such as flocculating constituent is small, degradation process is simple high-efficient, the power consumption is less, the degradation is stable.

Drawings

FIG. 1 is a schematic structural view of an electric flocculation apparatus;

FIG. 2 is a diagram showing PFOS degradation curves of reaction-1, reaction-2 and reaction-3 in examples 1 to 3;

FIG. 3 is a graph showing energy consumption of reaction-1, reaction-2 and reaction-3 in examples 1 to 3;

FIG. 4 is a graph showing the TOC removal rates of reaction-1, reaction-2 and reaction-3 in examples 1 to 3;

FIG. 5 is a graph of the cycle performance of reaction-3 in example 3.

Wherein, 1 is an electrolytic bath, 2 is an anode, 3 is a cathode, 4 is a direct current power supply, and 5 is a lead.

Detailed Description

For a more detailed understanding of the principles of operation, specific objects, aspects and advantages of the present invention. The invention is further described by the following figures and specific examples in conjunction with the description. It should be understood that the specific method examples described below are only for illustrating the present invention and are not intended to be limiting. Furthermore, the technical features mentioned in the embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

It will be understood that when an element is referred to as being "disposed on," "provided with," or "mounted on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. Any modification, equivalent replacement, improvement and the like made on the basis of the spirit and principle of the utility model should be included in the scope of the utility model.

Example 1

The embodiment provides an electric flocculation device, which comprises an electrolytic tank 1 with an open top (the size of the electrolytic tank is 200 x 80mm), 2 groups of

anodes

2 and 2 groups of cathodes 3, wherein the anodes 2 and the cathodes 3 are arranged in the electrolytic tank at intervals in parallel, the interval between every two adjacent anodes 2 and cathodes 3 is 1.7cm, and the anodes 2 and the cathodes 3 are iron plate electrodes with the size of 2.5 x 2.5 cm. The outermost anode 2 and the outermost cathode 3 are connected to a power source 4 (specifically, a dc power source), respectively, and the intermediate cathode 3 and the anode 2 are connected in series.

Referring to fig. 1, which is a schematic structural view of an electroflocculation apparatus, the anode 2 and the cathode 3 may be provided in multiple groups, and in example 1, both the anode 2 and the cathode 3 are provided in 2 groups.

The method for removing the perfluorinated organic pollutant solution by using the electric flocculation device comprises the following specific steps (marked as reaction 1):

(1) a5 mg/L (500mL) perfluorooctane sulfonic acid solution prepared in advance, a sodium chloride solution containing 0.08mol/L and a sodium monopersulfate solution containing 50mg/L were poured into the reaction vessel. The anode and the cathode are respectively connected with the anode and the cathode of a direct current power supply through leads.

(2) The DC power supply voltage was set to 55V and the current density was set to 6mA/cm ² The electrolysis time was set to 60 min.

The PFOS degradation curve under the working condition is shown in figure 2, and the PFOS degradation efficiency under the electrolysis condition of 60min is 97.6%. The energy consumption curve is shown in FIG. 3, and the energy consumption at 60min is 2.112 kWh/kg. The TOC removal curve is shown in FIG. 4, and the TOC removal rate at 60min is 92.1%.

Example 2

This example provides an electroflocculation apparatus of the same construction as example 1, except that there are 5 sets of anodes 2 and 5 sets of cathodes 3 in the cell, the spacing between adjacent anodes 2 and cathodes 3 is 1.5cm, and the anode and cathode electrode plates are 3.0 x 3.0cm in size; the outermost anode 2 and the outermost cathode 3 are respectively connected with a power supply 4 (specifically, a direct current power supply), and the 4 groups of anodes 2 and cathodes 3 on the middle side sequentially connect the adjacent anodes 2 and cathodes 3 in series two by two.

The method for removing the perfluorinated organic pollutant solution by using the electric flocculation device comprises the following specific steps (marked as reaction 2):

(1) a10 mg/L (500mL) solution of perfluorooctane sulfonic acid prepared in advance, containing 0.07mol/L sodium chloride solution and 75mg/L sodium peroxodisulfate solution, was poured into the reaction vessel. The anode and the cathode are respectively connected with the positive pole and the negative pole of a direct current power supply through leads.

(2) The DC power supply voltage was set to 75V and the current density was set to 8mA/cm ² The electrolysis time was set to 60 min.

The PFOS degradation curve under the working condition is shown in figure 2, and the PFOS degradation efficiency under the electrolysis condition of 60min is 98.5%. The energy consumption curve is shown in figure 3, and the energy consumption at 60min is 2.083 kWh/kg. The TOC removal curve is shown in FIG. 4, and the TOC removal rate at 60min is 94.3%.

Example 3

This example provides an electroflocculation apparatus of the same construction as in example 1, except that there are 3 sets of

anodes

2 and 3 sets of cathodes 3 in the cell, the spacing between adjacent anodes 2 and cathodes 3 being 2.0cm, the anode and cathode plates being 2.0 x 2.0cm in size; the outermost anode 2 and the outermost cathode 3 are respectively connected with a power supply 4 (specifically, a direct current power supply), and the 2 groups of

anodes

2 and 2 groups of cathodes 3 on the middle side sequentially connect every two adjacent anodes 2 and cathodes 3 in series.

The method for removing the perfluorinated organic pollutant solution by using the electric flocculation device comprises the following specific steps (marked as reaction 3):

(1) an 8mg/L (500mL) perfluorooctane sulfonic acid solution prepared in advance, a sodium chloride solution containing 0.10mol/L and a 65mg/L sodium monopersulfate solution were poured into the reaction vessel. The anode and the cathode are respectively connected with the positive pole and the negative pole of a direct current power supply through leads.

(2) The DC power supply voltage was set to 65V and the current density was set to 18mA/cm ² The electrolysis time was set to 60 min.

The PFOS degradation curve under the working condition is shown in figure 2, and the PFOS degradation efficiency under the electrolysis condition of 60min is 99.9%. The energy consumption curve is shown in FIG. 3, and the energy consumption at 60min is 2.060 kWh/kg. The TOC removal curve is shown in FIG. 4, and the TOC removal rate at 60min is 95.9%.

As shown in fig. 5, the reaction is performed under the working condition of example 3, after five times of PFOS circulation operations in-3 (the experimental conditions of each circulation operation are the same as those of example 3), the degradation efficiency is still high, and the degradation rate of the PFOS is 99.5%, which proves the high-efficiency degradation stability of the electroflocculation apparatus for the PFOS under the working condition.

According to the above, the utility model provides an electric flocculation device stability is high, when getting rid of perfluor organic pollutant with its use, gets rid of efficiently, and the power consumption is less, and reaction stability is strong.

The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be equivalent replacement modes, and all are included in the scope of the present invention.

Claims

1. An electric flocculation device is characterized by comprising an electrolytic bath (1), a plurality of groups of anodes (2) and a plurality of groups of cathodes (3); the anodes (2) and the cathodes (3) are arranged in the electrolytic tank in parallel at intervals, and the outermost anodes and the outermost cathodes are respectively connected with an external power supply (4); the adjacent cathodes (3) and anodes (2) on the middle side are connected in series in pairs.

2. An electroflocculation apparatus as claimed in claim 1, wherein the top of the electrolytic cell (1) is open.

3. An electroflocculation device according to claim 1, wherein the anode (2) is an iron plate electrode or an aluminum plate electrode; the cathode (3) is an iron plate electrode or an aluminum plate electrode.

4. An electroflocculation apparatus as claimed in claim 1, wherein the distance between adjacent anodes (2) and cathodes (3) is 1.5-2 cm.

5. An electroflocculation apparatus as claimed in claim 1, wherein the dimensions of the anode (2) and cathode (3) are 2.0-3.0 cm x 2.0-3.0 cm.

6. An electroflocculation apparatus as claimed in claim 1, wherein the anodes (2) and cathodes (3) are in groups of 2-5.

7. An electroflocculation device according to claim 1, wherein the power source (4) is a direct current power source.

8. An electric flocculation apparatus according to claim 7, wherein the DC supply voltage is 55-75V.