CN106976955A - Electrode, monopole room bioelectrochemistry equipment and the method for adjusting its hydraulic flow state - Google Patents

Abstract

It is in the fold electrode that " Z " font is bent the invention provides a kind of section, and is built in the bioelectrochemistry equipment of monopole room, thus, additionally provides a kind of method of adjustment of monopole room bioelectrochemistry equipment hydraulic flow state.Hydraulic flow state feature after adjusting and optimizing of the present invention can increase fouling of the electrode thing concentration, promote the degraded of fouling of the electrode thing, the actual residence time of extension pollutant in the reactor, reduce reactor dead volume, the problems such as slowing down channel, short stream.And the inventive method is simple to operation, with low cost, high-effect, the application potential for improving bioelectrochemistry equipment of high degree, in addition, the present invention can be used for the high-performance bio electro-chemical systems for handling high-concentration industrial-water, industrial park mixed type waste water and micro- pollutant effluents.

Description

Electrode, monopolar chamber bioelectrochemical device and method for adjusting its hydraulic flow regime

technical field

The invention belongs to the technical field of waste water treatment, and in particular relates to an electrode, a monopolar chamber bioelectrochemical device and a method for adjusting its hydraulic flow state.

Background technique

As an emerging water treatment technology, the bioelectrochemical system has attracted more and more attention and research for its great potential in refractory organic pollutants and resource and energy recovery. In the bioelectrochemical system, microorganisms are used as catalysts to convert chemical energy into electrical energy; in this technology, anode microorganisms efficiently utilize small molecular organic matter in wastewater, and domesticated cathode microorganisms use electrodes as electron donors to convert and degrade organic pollutants. The demand for the source electron donor is much smaller than that of the traditional anaerobic process; this technology accelerates the degradation of some refractory organic pollutants (nitroaromatic hydrocarbons, azo, high chlorine, etc.) through small energy input and control of potential conditions. Hydrocarbons, aromatic hydrocarbons, etc.) at the cathode for reductive degradation, and then achieve directional and efficient removal of these refractory pollutants. In addition, the bioelectrochemical system can also be organically coupled with the traditional anaerobic process, which greatly improves the space utilization rate of the anaerobic device, increases the biomass, and achieves efficient orientation of the refractory pollutants remaining in the anaerobic biological reaction. Transformation, overcome the disadvantages of less carbon source and low COD/TKN ratio in industrial wastewater, and strengthen the conversion and removal of refractory organic pollutants in wastewater.

The electrode is the core of the bioelectrochemical system. It is not only the acceptor (donor) interface carrier of electrons in the system, but also the carrier for microbial growth and attachment. Therefore, electrode performance will largely determine the performance of the entire biological electrochemical system. At present, the improvement of electrode performance is mainly through the following measures: (1) Optimization and modification of electrode materials, mainly doping nitrogen on carbon-based materials to improve the conductivity of materials, or seeking more Suitable metal matrix materials are used as electrodes; (2) The structure and morphology of the electrodes are optimized at the micro-nano scale, and electrodes with three-dimensional structures (glassy carbon, copper foam, nickel foam, etc.) are used to modify the structure of the electrode surface and group modification. All in all, these approaches are based on obtaining an electrode with high specific surface area, high electrical conductivity, high mechanical strength, strong biocompatibility, and low environmental impact. However, these modification methods are difficult to achieve large-scale engineering application in terms of operation and cost.

To realize the large-scale engineering application of bioelectrochemical systems, the hydraulic flow characteristics of the reaction device must also be considered. To some extent, the hydraulic flow characteristics are the most important design parameters to determine the operating efficiency of the reactor, because the hydraulic flow characteristics greatly affect the mass transfer between the media in the reactor, the removal rate of organic pollutants, the sludge Production and biofilm growth as well as the overall space utilization efficiency of the reactor, etc.

Contents of the invention

(1) Technical problems to be solved

The object of the present invention is to provide an electrode, a monopolar chamber bioelectrochemical device and a method for adjusting its hydraulic flow state, so as to solve the above technical problems.

(2) Technical solutions

In one aspect of the present invention, an electrode is provided, and the electrode is a folded electrode whose section is bent in a "Z" shape.

Optionally, the bending angle of the folded electrode is 10°-120°.

Optionally, the bending angle of the folded electrode is 40°-60°.

Optionally, the electrode is made of stainless steel mesh, and the mesh size of the stainless steel mesh is 24-80 mesh.

Another invention of the present invention also provides a monopolar chamber bioelectrochemical device, comprising an anode and a cathode, both of which are electrodes described in any one of claims 1-4.

Optionally, an insulating sheet is also included, the bending angle of the insulating sheet is consistent with that of the wrinkled electrode, and is used to separate the anode from the cathode, and to adjust the gap between the anode and the cathode. The distance between the anode and the cathode is 0.1 mm to 10 mm.

In yet another aspect of the present invention, a method for adjusting the hydraulic flow state of a monopolar chamber bioelectrochemical device is provided, comprising the steps of:

S1. Prepare a folded electrode with a "Z"-shaped cross-section;

S2. Built the wrinkled electrode into the device as an anode and a cathode respectively;

S3. Changing the bending angle of the pleated electrodes and/or the distance between the anode and the cathode to adjust the hydraulic flow state of the device.

Optionally, the distance between the anode and the cathode is set at 0.1mm˜10mm.

Optionally, step S1 includes the steps of:

S11. Folding the electrode into a wrinkled shape to obtain a wrinkled electrode;

S12, performing surface treatment on the wrinkled electrode;

S13. Connect the processed pleated electrode to a wire, and lead out a section of wire as a current collector.

(3) Beneficial effects

As can be seen from the above technical solutions, the present invention has the following advantages:

(1) The electrode material that the present invention uses adopts stainless steel net, at first, stainless steel net has high mechanical strength, and it can carry out machining and forming preferably; Secondly, stainless steel has stronger chemical stability, acid and alkali resistance and corrosion, widely It is suitable for various wastewater quality characteristics; third, stainless steel has good conductivity and low resistivity, and is suitable for use as an electrode conductor; finally, compared with other types of electrode materials, stainless steel is cheap and easy to obtain;

(2) The electrode morphology of the present invention can be obtained by simply folding the stainless steel mesh by an industrial bending machine, and only ethanol, acetone and acid solution are used for the surface treatment of the electrode. The processing and treatment method of the electrode is simple, easy to operate, and industrial Low cost, easy for large-scale industrial production;

(3) The built-in pleated electrode of the present invention will greatly improve the characteristics of the hydraulic flow state in the bioelectrochemical device, and the improvement of the hydraulic flow state will promote the mass transfer between different media in the device and increase the concentration of the electrode surface pollution concentration, accelerate the removal rate of organic pollutants, reduce sludge production, promote biofilm growth, and make full use of the overall space of the reactor;

(4) In the present invention, electrodes of different structures can be adjusted by adjusting the bending angle of the pleated electrode and the size of the insulating sheet, so as to obtain different hydraulic flow characteristics and have greater controllability.

Description of drawings

FIG. 1 is a schematic structural view of a wrinkled electrode according to an embodiment of the present invention;

2 is a schematic structural view of a monopolar chamber bioelectrochemical device according to an embodiment of the present invention;

Fig. 3 is a schematic structural view of an insulating plastic sheet according to an embodiment of the present invention;

4 is a schematic diagram of the method steps for adjusting the hydraulic flow state of the monopolar chamber bioelectrochemical equipment according to the embodiment of the present invention;

Fig. 5 is the cutting schematic diagram of stainless steel mesh in Fig. 4;

Fig. 6 is a schematic diagram of the electrode connection of the folded electrode in Fig. 4;

Fig. 7 is a curve diagram of improving the residence time distribution of the bioelectrochemical device with different bending angles and the distance between the anode and the cathode of the wrinkled electrode according to the embodiment of the present invention;

Fig. 8 is a comparison diagram of different bending angles of the wrinkled electrode and the distance between the anode and the cathode to improve the actual residence time of the bioelectrochemical system according to the embodiment of the present invention;

Fig. 9 is a comparison chart of the removal efficiency of dyes in the mixed wastewater of AO7 treated by the bioelectrochemical device with built-in pleated electrodes according to the embodiment of the present invention.

detailed description

Using prior art modification methods, electrodes with high specific surface area, high electrical conductivity, high mechanical strength, strong biocompatibility and low environmental impact are generally obtained. However, these modification methods are difficult to achieve large-scale engineering application in terms of operation and cost.

Furthermore, the bioelectrochemical system includes multiphase systems such as wastewater, sludge, biofilm, electrodes, and gas. The hydraulic flow effect will be amplified in the bioelectrochemical system and will affect the bioelectrochemical system to a greater extent. of operating efficiency. Therefore, through the structural design and surface treatment of the electrode under the condition of industrial scale, and adopting the adjustment and optimization method to build it into the reactor, to obtain an optimized built-in electrode bioelectrochemical device will be a large-scale engineering of the bioelectrochemical system. the only way.

The present invention is mainly to solve the problems of high electrode cost and poor hydraulic fluidity faced by the bioelectrochemical system in the process of realizing large-scale and engineering application, and at the same time, in order to realize the scale-up application of the built-in electrodes of the bioelectrochemical system, it provides a A method to adjust the hydraulic flow state of bioelectrochemical equipment with built-in folded electrodes, and apply this method to construct bioelectrochemical equipment to treat refractory organic pollutants in high-concentration industrial wastewater, mixed wastewater in industrial parks, and micro-polluted wastewater.

Based on the above, on the one hand, the present invention provides a method for adjusting and optimizing the hydraulic flow state of bioelectrochemical equipment through built-in folded electrodes, and provides bioelectrochemical equipment constructed by this method in the treatment of azo-containing, nitro Application of wastewater with aromatic hydrocarbons, aromatic hydrocarbons and other pollutants. The electrode of the present invention is applied to bioelectrochemical equipment in a monopolar chamber, and the hydraulic flow state is adjusted and optimized, which can be used to treat high-concentration industrial wastewater, mixed wastewater in industrial parks and slightly polluted wastewater. Moreover, the method of the present invention is simple and easy to operate, low in cost and high in efficiency, and greatly improves the application potential of the monopolar chamber bioelectrochemical system.

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

The technical solutions provided by the present invention are not limited to the specific implementations listed below, but also include any combination and parameter adjustment of various specific implementations.

One aspect of the embodiment of the present invention provides an electrode. Figure 1 is a schematic diagram of a wrinkled electrode according to an embodiment of the present invention. The electrode, wherein, h1 is the height of the wrinkled electrode wrinkled region, h2 is the height of the current collecting area of the wrinkled electrode, α is the bending angle of the wrinkled electrode, δ is the length of the wrinkled edge, and W is the width of the conductive material for preparing the electrode. The cross section of the folded electrode is bent in a "Z" shape, and the bending angle is 10°-120°, more preferably 40°. ~60°, and the bending angle is controlled within this range. When the electrode is used in a monopolar bioelectrochemical device, the hydraulic flow characteristics of the device can be better adjusted and optimized, and the sewage can be removed more effectively. refractory pollutants. In addition, the electrodes are ductile and not easily corroded conductive materials, such as metals such as stainless steel and titanium, or carbon bases such as carbon felt, graphite plate, and graphite felt. In the embodiment of the present invention, stainless steel is selected for the reasons: firstly, stainless steel mesh has high mechanical strength, which can be machined and formed better; secondly, stainless steel has strong chemical stability, acid and alkali resistance and corrosion resistance, and is widely used in Various wastewater quality characteristics; third, stainless steel has good conductivity and low resistivity, and is suitable for use as an electrode conductor; finally, compared with other types of electrode materials, stainless steel is cheap and easy to obtain.

Another aspect of the embodiment of the present invention also provides a monopolar chamber bioelectrochemical device, FIG. 2 is a schematic structural diagram of the monopolar chamber bioelectrochemical device according to the embodiment of the present invention, as shown in FIG. 2 , which includes: External resistance 4, external power supply 5, water inlet 6, pleated anode 7, pleated cathode 8, water outlet 9 and insulating plastic sheet (not shown in Figure 2, please refer to Figure 3). Wherein, the cross-sections of the wrinkled cathode and the wrinkled anode are bent in a "Z" shape, and the electrode material is a conductive material that is ductile and not easily corroded. Figure 3 is a schematic structural view of the insulating plastic sheet of the embodiment of the present invention, as shown in Figure 3, h3 is the height of the wrinkled insulating plastic sheet, β is the bending angle of the wrinkled insulating plastic sheet, d is the anode and the cathode the distance between. An insulating sheet (such as an insulating plastic sheet) should be placed between the cathode and cathode at the same bending angle as the wrinkled electrode to maintain a constant distance between the anode and the cathode and an insulating environment between the anode and the cathode, while preventing the two An electrode contact is shorted. Because the device is a unipolar chamber device, there are small holes on the insulating sheet to facilitate the flow of sewage in the anode and cathode, which is more conducive to the transmission of ions between the anode and cathode, and degrades refractory organic matter in sewage. Such as nitroaromatic hydrocarbons, azo, high chlorinated hydrocarbons, aromatic hydrocarbons, etc.

In another aspect of the embodiment of the present invention, a method for adjusting the hydraulic flow state of the bioelectrochemical equipment in the monopolar chamber is also provided. Figure 4 shows the steps of the method for adjusting the hydraulic flow state of the bioelectrochemical equipment in the monopolar chamber according to the embodiment of the present invention The schematic diagram, as shown in Figure 4, includes steps:

Step S1: Prepare a wrinkled electrode with a cross-section bent in a "Z" shape, and step S1 is specifically:

First, proceed to step S11: use stainless steel mesh as the electrode material, and cut the industrial stainless steel mesh to a stainless steel mesh of a specific required size. Figure 5 is a schematic diagram of cutting the stainless steel mesh in Figure 4. As shown in Figure 5, We is the electrode width, Le is the length of the stainless steel mesh. Then, the cut stainless steel mesh is folded into a fixed bending angle on an industrial bending machine, so as to obtain a folded electrode with a "Z"-shaped cross section (please refer to Figure 1).

In the embodiment of the present invention, the stainless steel mesh adopts 300 series stainless steel mesh (chromium-nickel austenitic stainless steel), preferably 304, 304L, 316 and 316L stainless steel mesh, more preferably 316L stainless steel mesh; the stainless steel mesh mesh specification 24-80 mesh, more preferably 30-50 mesh; the bending angle of the wrinkled electrode is 10°-120°, more preferably 40°-60°.

Next, proceed to step S12: cleaning the surface of the prepared wrinkled electrode with a mixture of ethanol and acetone, soaking the surface with an acid solution after cleaning, rinsing with deionized water after soaking, and drying at room temperature. In the embodiment of the present invention, the volume ratio of ethanol to acetone in the ethanol-acetone mixture is 0.5-2, more preferably 1; the acid is HNO ₃ , HCl and H ₂ 5O with a concentration of 0.5-1.5 mol/L ₄ , more preferably 1mol/L H ₂ 5O ₄ ; the soaking treatment time is 16-32 hours, more preferably 24 hours.

Then, proceed to step S13: connect the wrinkled electrode to the wire through non-corrodible screws (such as plastic screws), and lead out a section of the wire as a current collector. Figure 6 is a schematic diagram of the electrode connection of the folded electrode in Figure 4. As shown in Figure 6, a hole is punched in the electrode current collecting area, and one end of the titanium wire is made into a ring shape with a tool, and the ring shape of the titanium wire is connected to the electrode current. The holes in the collecting area are connected with plastic screws 3 . A layer of heat-shrinkable tube 2 is put on the remaining titanium wire, and a section of titanium wire is exposed at the other end, and the whole is used as a current collector 1 . In the embodiment of the present invention, titanium wire is selected, copper wire or gold wire can also be selected, because it is not easy to be corroded by water and oxygen, and the diameter of titanium wire is 1mm-2mm, more preferably 1.5mm.

In addition, the length (L) of the stainless steel mesh is determined by the bending angle (α) and the electrode height (h) of the pleated electrode, and the specific size calculation formula of L is:

In step S2, two identical folded electrodes are built into the bioelectrochemical device in the monopolar chamber as the anode and the cathode respectively.

Step S3, changing the bending angle of the pleated electrode and/or the distance between the anode and the cathode to adjust the hydraulic flow state of the device, specifically:

The distance between the anode and the cathode is changed by changing the position of the insulating plastic sheet in the device. Generally speaking, the distance between the anode and the cathode is 0.1 mm to 10 mm, preferably 0.2 mm. The hydraulic flow regime can be changed by changing the distance between the anode and the cathode, and in addition, the hydraulic flow regime can also be changed by changing the folded electrode.

Generally speaking, the residence time distribution curve can be obtained by ion tracer method or the flow field characteristics of the reaction system can be simulated by computational fluid dynamics to characterize the hydraulic flow regime. Among them, computational fluid dynamics is based on computer simulation, which will not be repeated here. In the embodiment of the present invention, the residence time distribution curve is obtained by the ion tracer method to characterize the hydraulic flow state. Using lithium sulfate (Li ₂ SO ₄ ) as a tracer, the residence time distribution curve of the bioelectrochemical device with built-in wrinkled electrodes was measured by ion tracer method, and then by adjusting the bending angle of the wrinkled electrodes and the width of the plastic insulating sheet to Different distances between the anode and the cathode are maintained, so that a bioelectrochemical device with an optimized hydraulic flow state is obtained by adjusting the bending angle of the wrinkled electrode and the distance between the anode and the cathode.

Prove the inventive effect of the present invention by following examples:

Example 1:

In the embodiment of the present invention, the 304 stainless steel mesh with an aperture specification of 50 meshes is cut into 2 pieces of stainless steel mesh with a size of 80mm (We) × 1470mm (Le), and the cut stainless steel mesh is folded by an industrial bending machine , so that the length δ of the electrode wrinkle is 30 mm, and the bending angle α of the wrinkled electrode is 40°; the height of the whole electrode is 550 mm, among which the height h1 of the wrinkle area of the wrinkle electrode is 500 mm, and the height h2 of the current collecting area is 50 mm; the bending angle Two electrodes with α of 40° were soaked in a mixture of ethanol: acetone = 1 (volume ratio), and cleaned under ultrasonic conditions at room temperature for 15 minutes; the cleaned electrodes were dipped dry and placed in H ₂ Soak in SO ₄ solution for 24 hours at room temperature, then take out the electrode, rinse it with deionized water for 3 times, and then dry it. Drill a hole in the electrode current collecting area, the diameter of the hole is 8mm, select a titanium wire with a diameter of 2mm, make one end of the titanium wire into a ring shape with a diameter of 8mm, and connect the ring shape of the titanium wire with the electrode current collector The holes in the area are connected with M8 plastic screws 3. Put a layer of heat-shrinkable tube 2 on the remaining titanium wire, and expose a 10 cm long titanium wire at the other end, and use the whole as a current collector 1 . The prepared two electrodes are placed in a plexiglass reactor with a size of 80mm (Wr) × 36mm (Lr) × 580mm (Hr), and a size of 500mm (h3 )×2mm(d), a pleated insulating plastic sheet with a bending angle β of 40°, keeping the distance between the anode and cathode at 2mm. The anode and the cathode are connected with an external power supply 5, an external resistance 4 and a data acquisition system to form a bioelectrochemical device. After successful assembly, using Li ₂ SO ₄ as a tracer, the ion tracer method was used to study the residence time distribution of Li ⁺ under the conditions of theoretical hydraulic retention time of 2h, 4h, 6h and 8h respectively in the bioelectrochemical device with built-in folded electrodes curves to characterize. After the fluid state characterization, 10 mL of sludge was inoculated into the bioelectrochemical equipment, and then domesticated and cultivated under the condition of an applied voltage of 0.5 V to enrich and cultivate the microorganisms of the anode electrode module in situ. During the experiment, municipal sewage added with 100 mg/L acid orange 7 (AO7) was used to verify the degradation efficiency of this example on refractory organic pollutants under the conditions of theoretical hydraulic retention time of 2h, 4h, 6h and 8h.

Example 2:

The same as in Example 1, the only difference is that the 50-mesh 304 stainless steel mesh is cut into two pieces of stainless steel mesh with a size of 80mm (We) × 2930mm (Le), and the bending angle α of the pleated electrode is 20°. The prepared two electrodes are placed in a plexiglass reactor with a size of 80mm (Wr) × 44mm (Lr) × 580mm (Hr), and a size of 500mm (h3 )×2mm(d), a pleated insulating plastic sheet with a bending angle β of 20°, keeping the distance between the anode and cathode at 2mm.

Example 3:

Same as Example 1, the only difference is that the prepared two electrodes are placed in a plexiglass reactor with a size of 80mm (Wr) × 40mm (Lr) × 580mm (Hr), and they are attached to the two side walls of the reactor. A pleated insulating plastic sheet with a size of 500mm(h3)×6mm(d) and a bending angle β of 20° is placed on the edge, and the distance between the anode and the cathode is maintained at 4mm.

Comparative example:

In order to be consistent with the electrode area in Example 1, in the comparative example, the 304 stainless steel mesh with an aperture specification of 50 meshes was cut into 6 pieces of stainless steel mesh with a size of 80mm×490mm, and the 6 pieces of flat electrodes were soaked in ethanol: acetone=1 (volume ratio) in the mixed solution, clean at room temperature under ultrasonic conditions for 15min; dip the cleaned electrode dry, place it in a H ₂ SO ₄ solution with a concentration of 1mol/L, soak it at room temperature for 24h, and then take out the electrode , rinsed 3 times with deionized water and wiped dry. Drill a hole on the electrode, the diameter of the hole is 8mm, choose a titanium wire with a diameter of 2mm, make one end of the titanium wire into a ring shape with a diameter of 8mm, and connect the ring shape of the titanium wire and the hole on the electrode with M8 Plastic screws for connection. Put a layer of heat-shrinkable tube on the remaining titanium wire, and expose a 10cm long titanium wire at the other end, and use the whole as a current collector. The prepared two electrodes are placed in a reactor with a size of 80mm (length) × 36mm (width) × 580mm (height), and the size is 500mm (h3) × A 2 mm (d) pleated sheet of insulating plastic maintains a distance of 2 mm between the anode and cathode. The anode and the cathode are connected with an external power supply 5, an external resistance 4 and a data acquisition system to form a bioelectrochemical device. After successful assembly, using Li ₂ SO ₄ as a tracer, the ion tracer method was used to study the residence time distribution of Li ⁺ under the conditions of theoretical hydraulic retention time of 2h, 4h, 6h and 8h respectively in the bioelectrochemical device with built-in folded electrodes curves to characterize. After the fluid state characterization, 10 mL of sludge was inoculated into the bioelectrochemical equipment, and then domesticated and cultivated under the condition of an applied voltage of 0.5 V to enrich and cultivate the microorganisms of the anode electrode module in situ. During the experiment, municipal sewage added with 100 mg/L acid orange 7 (AO7) was used to verify the degradation efficiency of this example on refractory organic pollutants under the conditions of theoretical hydraulic retention time of 2h, 4h, 6h and 8h.

Next, verify the hydraulic flow characteristics of the bioelectrochemical device:

Fig. 7 is the electrode of the embodiment of the present invention and existing electrode to improve the residence time distribution curve of bioelectrochemical equipment, as shown in Fig. 7, the residence time distribution curve that embodiment 1, embodiment 2 and embodiment 3 obtain ( RTD) compared to the residence time distribution curve in the comparative example: when the peak value of the RTD appears at 0.35θ in the comparative example, the peak value of the RTD in the embodiment 1, the embodiment 2 and the embodiment 3 delays to some extent, occurs respectively at 0.57θ, 0.61θ, and 1.26θ; multiple small peaks appear in the RTD in the comparative example, indicating that channeling or multi-channel phenomenon exists in the comparative example, while this phenomenon has alleviated.

Fig. 8 is the electrode of the embodiment of the present invention and existing electrode to improve the actual residence time comparison figure of bioelectrochemical system, as shown in Fig. 8, when the water inflow rate of embodiment 1, embodiment 2, embodiment 3 and comparative example When being fixed at different theoretical HRTs (2, 4, 6 and 8h), the actual residence time/theoretical residence time obtained in embodiment 1, embodiment 2 and embodiment 3 will be greater than 1, and the embodiment will be far less than 1, When theoretical HRT is 2h, the actual residence time/theoretical residence time value of embodiment 1, embodiment 2, embodiment 3 and comparative example are respectively 1.23, 1.06, 1.09 and 0.75; When theoretical HRT is 4h, embodiment 1 , embodiment 2, embodiment 3 and the actual residence time/theoretical residence time value of comparative example are respectively 1.24,1.13,1.10 and 0.83; When theoretical HRT is 6h, embodiment 1, embodiment 2, embodiment 3 and comparison The actual residence time/theoretical residence time value of example is respectively 1.36, 1.14, 1.05 and 0.88; When theoretical HRT is 6h, the actual residence time/theoretical residence time value of embodiment 1, embodiment 2, embodiment 3 and comparative example They are 1.24, 1.15, 1.06 and 0.84, respectively.

The above result explanation: compared with comparative example, the dead volume of the reactor in embodiment 1, embodiment 2 and embodiment 3 reduces to a great extent, increases the reactor space utilization rate, prolongs the actual time of pollutants in the reactor. dwell time. Therefore, the present invention also shows that the water flow characteristics of bioelectrochemical equipment can be greatly improved by the method of built-in folded electrodes.

Next, verify the removal of organic pollutants from bioelectrochemical devices:

Fig. 9 is the electrode of the embodiment of the invention and the existing electrode in bioelectrochemical equipment processing AO7 The mixed type waste water compares the removal efficiency of dyestuff, as shown in Fig. 9, embodiment 1, embodiment 2, embodiment 3 and comparison When the bioelectrochemical device with built-in pleated electrodes to adjust the flow state described in the example treats wastewater containing refractory pollutants, when the AO7 concentration in the influent is controlled to about 100 mg.L-1, the hydraulic retention time (HRT ) to increase the dye load. During the continuous experiment, the HRT is controlled in four stages of 8h, 6h, 4h and 2h. The dye loads corresponding to these four stages are 300g.m ^{- 3} .d ^-1 , 400g.m ^-3 .d ^-1 , 600g.m ^-3 .d ^-1 and 1200g.m ^-3 .d ^-1 ; the removal rates of AO7 in Example 1 were 89.91±0.43%, 85.48±1.98%, 63.48±1.43% and 52.57 ± 1.66%; AO removal rate in embodiment 2 is 91.08 ± 0.75%, 84.70 ± 3.64%, 75.54 ± 3.49% and 62.6 ± 21.48% respectively; AO removal rate in embodiment 3 is 76.56 ± 0.75% respectively , 74.03±3.64%, 61.04±3.49% and 43.18±1.48%; however, the removal rates of AO7 in comparative examples were 52.37±2.41%, 49.94±3.68%, 35.71±2.01% and 22.61±0.42%, respectively. The above results can significantly verify the advantages of the bioelectrochemical device in this example that adjusts the flow state through built-in folded electrodes in the treatment of wastewater.

The specific embodiments described above have further described the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above descriptions are only specific embodiments of the present invention, and are not intended to limit the present invention. Within the spirit and principles of the present invention, any modifications, equivalent replacements, improvements, etc., shall be included in the protection scope of the present invention.

Claims (9)

1. An electrode, characterized in that the electrode is a wrinkled electrode whose section is bent in a "Z" shape. 2 . The electrode according to claim 1 , wherein the bending angle of the wrinkled electrode is 10°-120°. 3. The electrode according to claim 1, characterized in that, the bending angle of the wrinkled electrode is 40°-60°. 4. The electrode according to claim 1, characterized in that, the material of the electrode is stainless steel mesh, and the mesh size of the stainless steel mesh is 24-80 mesh. 5. A monopolar chamber bioelectrochemical device, characterized in that it comprises an anode and a cathode, both of which are electrodes described in any one of claims 1-4. 6. The monopolar chamber bioelectrochemical device according to claim 5, further comprising an insulating sheet, the bending angle of the insulating sheet is consistent with the bending angle of the wrinkled electrode, and is used to separate the anode and the The cathode, and for adjusting the distance between the anode and the cathode, the distance between the anode and the cathode is 0.1mm˜10mm. 7. A method for adjusting the hydraulic flow state of a monopolar chamber bioelectrochemical device, characterized in that it comprises the steps of: S1. Prepare a folded electrode with a "Z"-shaped cross-section; S2. Built the wrinkled electrode into the device as an anode and a cathode respectively; S3. Changing the bending angle of the pleated electrodes and/or the distance between the anode and the cathode to adjust the hydraulic flow state of the device. 8. The method according to claim 7, characterized in that, the distance between the anode and the cathode is set at 0.1mm˜10mm. 9. The method according to claim 7, wherein step S1 comprises the steps of: S11. Folding the electrode into a wrinkled shape to obtain a wrinkled electrode; S12, performing surface treatment on the wrinkled electrode; S13. Connect the processed pleated electrode to a wire, and lead out a section of wire as a current collector.