CN115893576A - A new photocatalytic sewage treatment equipment and process based on microwave irradiation - Google Patents

Abstract

The invention discloses a novel photocatalysis sewage treatment device and a novel photocatalysis sewage treatment process based on microwave irradiation, wherein the device comprises a reaction box body, a plurality of galleries are arranged in the reaction box body, two adjacent galleries are separated by a partition plate and are mutually communicated through a detection port, a plurality of catalyst polar plates and ultraviolet lamp tubes are arranged in each gallery, and the catalyst polar plates and the ultraviolet lamp tubes are arranged at intervals; a microwave transmitting antenna is arranged at the central position of each gallery, and the axis of the microwave transmitting antenna is vertical to the catalyst polar plate; the invention combines microwave and photocatalysis, can greatly improve the reaction rate, and has the characteristics of obvious high efficiency, no pollution and the like; under the action of microwave irradiation, the photocatalyst can generate polarization, which is beneficial to the generation of hydroxyl free radicals, enhances the activity of the photocatalyst and improves the removal rate of pollutants.

Description

A new photocatalytic sewage treatment equipment and process based on microwave irradiation

technical field

The invention relates to the technical field of sewage treatment, in particular to a novel photocatalytic sewage treatment equipment and process based on microwave radiation.

Background technique

The information disclosed in this background section is only intended to increase the understanding of the general background of the present invention, and is not necessarily taken as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to those skilled in the art.

Wastewater from pharmaceutical, chemical, printing and dyeing industries often contains toxic and harmful substances such as phenols, benzenes, and antibiotics, and some heterocyclic organic compounds are extremely difficult to degrade. Advanced oxidation technology is usually used to decompose them into short-chain, biodegradable After the small molecular substances are obtained, they are further processed by biochemical methods. Common advanced oxidation technologies, such as ozone catalytic oxidation, Fenton oxidation, electrocatalytic oxidation, etc., mostly have complex processes and high investment costs. As an important component of advanced oxidation technology, photocatalytic technology has the advantages of simple process, low investment cost and no secondary pollution.

Chinese invention patent-CN106006833A discloses a wastewater photocatalytic treatment device, including a plurality of ultraviolet lamps and photocatalyst plates, which enter the photocatalytic treatment device after fully mixing the oxidant solution and sewage, but this device exists in the process of wastewater treatment. The following problems: in the process of photocatalysis, the recombination rate of e ^- /h ⁺ is high, the yield of OH is low, the reaction rate is slow, the suspension catalyst is difficult to recycle, and the photoexcited catalyst is restricted by factors such as water chroma and turbidity, which makes wastewater treatment difficult. low efficiency.

Contents of the invention

Aiming at the problems existing in the prior art, the present invention provides a novel photocatalytic sewage treatment equipment and process based on microwave irradiation. By introducing microwave irradiation into the photocatalytic wastewater treatment system, compared with a single photocatalytic technology, the microwave effect It can generate e ^- or h ⁺ capture centers, inhibit e ^- /h ⁺ recombination in photocatalysis, and facilitate the generation of free OH, thereby increasing the efficiency of wastewater treatment and increasing the reaction rate.

Technical scheme of the present invention is as follows:

In the first aspect of the present invention, a new type of photocatalytic sewage treatment equipment based on microwave irradiation is provided, including a reaction box, and a plurality of corridors are arranged in the reaction box, and between two adjacent corridors Separated by partitions and communicated with each other through the detection port, a plurality of catalyst plates and ultraviolet lamp tubes are arranged in each corridor, and the catalyst plates and ultraviolet lamp tubes are arranged at intervals; set in the center of each corridor There is a microwave transmitting antenna whose axis is perpendicular to the catalyst plate.

In some embodiments of the present invention, there are three corridors, including a first corridor, a second corridor and a third corridor.

In some embodiments of the present invention, a water inlet is provided at the lower part of the first corridor, and the water inlet is connected with a water inlet pipe.

In some embodiments of the present invention, a temperature sensor is arranged on the top of the third corridor, and the temperature sensor is inserted into the inside of the box, and a water outlet is arranged above the side wall of the third corridor, and the water outlet Connect to the outlet pipe.

In some embodiments of the present invention, an aeration inlet is provided at the lower part of each of the corridors, and the aeration inlet is sequentially connected with an aeration pipe and an aeration fan.

In some embodiments of the present invention, the catalyst plate and the ultraviolet lamp tube are arranged in parallel and at intervals, two ultraviolet lamp tubes are arranged between two adjacent catalyst plates, and there is a certain distance between the two ultraviolet lamp tubes .

In some embodiments of the present invention, the microwave transmitting antenna is located between two ultraviolet lamp tubes and passes through the catalyst plate.

In some embodiments of the present invention, the microwave transmitting antenna is connected with a microwave generator, and the microwave generator is arranged outside the reaction box.

In some embodiments of the present invention, the detection ports are arranged on the upper part of the partition and arranged in an S shape.

In the second aspect of the present invention, a novel photocatalytic sewage treatment process based on microwave irradiation is provided. The sewage enters the interior of the reaction box, and the sewage is treated by utilizing the synergistic effect of microwave irradiation and photocatalysis.

One or more technical solutions of the present invention have the following beneficial effects:

(1) The new photocatalytic sewage treatment equipment based on microwave irradiation provided by the present invention combines microwave and photocatalysis, which can greatly improve the reaction rate, and has obvious characteristics such as high efficiency and no pollution; under the action of microwave irradiation, it can Polarize the photocatalyst, which is beneficial to the generation of hydroxyl radicals, enhance the activity of the photocatalyst, and improve the removal rate of pollutants; in addition, the microwave effect can generate e ^- or h ⁺ capture centers, which can inhibit the e ^- /h in photocatalysis ⁺ Composite, which is conducive to the generation of free OH, thereby increasing the efficiency of wastewater treatment;

(2) The present invention fixes the catalyst on the pole plate in the form of a coating, which is convenient for recycling and can be reused, avoiding the disadvantage that the powder catalyst is difficult to recycle, and the reaction device is equipped with an aeration system to accelerate the agitation of the water flow, so that Suspended substances in the water flow out with the water, thereby preventing particles from settling on the plate and shielding the catalyst from exposure to ultraviolet light.

(3) The microwave radiation used in the present invention is directly introduced into the water through the microwave transmitting antenna, and there is an airtight waterproof casing on the outside. The device is simple, easy to operate, no additional building structures are needed, and it can be placed outdoors directly, with a small footprint.

(4) In the new photocatalytic sewage treatment equipment based on microwave irradiation provided by the present invention, ultraviolet lamps and microwave transmitting antennas are evenly arranged in each corridor to ensure uniform irradiation of sewage, and sewage S-shaped flows through each corridor, It can be treated in multiple stages by microwave photocatalysis to improve the efficiency of pollutant removal.

Description of drawings

Fig. 1 is a structural schematic diagram of a novel photocatalytic sewage treatment equipment based on microwave irradiation of the present invention.

In the figure: 1-control cabinet; 2-reaction box; 3-microwave generator; 4-catalyst plate; 5-ultraviolet lamp; 6-microwave transmitting antenna; 7-aeration fan; 8-water inlet pipe; - the first corridor; 10 - the second corridor; 11 - the third corridor; 12 - the outlet pipe; 13 - the temperature sensor; 14 - the aeration pipe; 15 - the partition; 16 - the detection port.

Detailed ways

It should be noted that the following detailed description is exemplary and intended to provide further explanation of the present invention. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

Example 1

In a typical implementation of the present invention, a new type of photocatalytic sewage treatment equipment based on microwave irradiation is proposed, including a reaction box 2, a plurality of corridors are arranged in the reaction box 2, and two adjacent The corridors are separated by a partition plate 15 and communicated with each other through a detection port 16. A plurality of catalyst plates 4 and ultraviolet lamps 5 are arranged in each corridor, and the catalyst plates 4 and ultraviolet lamps 5 are spaced apart. Setting; a microwave transmitting antenna 6 is arranged at the center of each corridor, and the axis of the microwave transmitting antenna 6 is perpendicular to the catalyst plate 4 .

Three corridors are arranged in the reaction box, and the corridors are rectangular cavity structures, including the first corridor 9, the second corridor 10 and the third corridor 11. The structure in each corridor is the same, and catalyst plates are arranged. , ultraviolet lamp tube and microwave transmitting antenna, wherein, the bottom of the first corridor 9 is provided with a water inlet, the water inlet is connected with the water inlet pipe 8, and the sewage enters the first corridor 9 through the water inlet pipe, and the third corridor 11 A temperature sensor 13 is arranged on the top of the tank, and the temperature sensor 13 is inserted into the box body, and a shielding device is set on it to effectively eliminate the interference of electromagnetic waves. The temperature sensor is used to monitor the water temperature in real time, and is linked with the microwave generator 3 through the control system. After the temperature range, the required temperature can be controlled by automatically adjusting the microwave power. Set the temperature control range to 35-80°C, and adjust the microwave output power through the control program to achieve the purpose of temperature control and prevent the outlet water temperature from being too high. A water outlet is provided above the side wall of the third corridor, and the water outlet is connected to the water outlet pipe 12, and the treated waste water is discharged out of the reaction box through the water outlet.

The lower part of each corridor is provided with an aeration inlet, and the aeration inlet is connected to the aeration pipe 14 and the aeration fan 7 in sequence; the aeration fan continues to aerate the reaction device to accelerate the agitation of the water flow, improve the microwave, The contact probability of catalyst, light and pollutants is beneficial to the removal of pollutants. At the same time, part of the oxygen is provided for the reaction box, and a small amount of ozone can be generated under the irradiation of the ultraviolet lamp. Ozone has strong oxidizing properties, and it also has a certain degradation effect on pollutants in the water body.

In this embodiment, the catalyst plate 4 and the ultraviolet lamp tube 5 are arranged in parallel and at intervals, and two ultraviolet lamp tubes are arranged between two adjacent catalyst plates 4, and there is a certain distance between the two ultraviolet lamp tubes. , to ensure uniform irradiation of ultraviolet light, the microwave transmitting antenna 6 is located between two ultraviolet lamps and passes through the catalyst plate, further, the microwave transmitting antenna is connected with the microwave generator 3, and the microwave generator 3 It is arranged outside the reaction box 2, and the generated microwave is transmitted to the microwave transmitting antenna through the waveguide, and then irradiated into the water. The microwave transmitting antenna is arranged in each corridor according to the irradiation area. There is a PP shell outside the microwave transmitting antenna, so as to Guaranteed airtight waterproof.

The catalyst plate 4 is a hollow plate with well-developed pores and a large specific surface area, and the surface is coated with a nano-titanium dioxide coating as a photoreaction catalyst. The developed pores can fully increase the contact area of catalyst, ultraviolet light and sewage. The thickness of the pole plate is 1-2cm, and the pole plate is aluminum base, which has certain strength and impact resistance. The two sides of each corridor of the reaction box are jagged slots for easy installation and replacement of catalyst plates, and the arrangement density of catalyst plates can also be adjusted according to the sewage water quality. The wavelength of the ultraviolet lamp is 254nm, the diameter is 30mm, and the outside is a quartz glass tube, which has waterproof function and can be directly arranged in water. The quartz glass tube has strong light transmission and does not affect the transmission of ultraviolet light. Adjust the arrangement density of ultraviolet lamps according to the sewage water quality.

In this embodiment, the detection port 16 is arranged on the upper part of the partition, specifically, the detection port between the first corridor 9 and the second corridor 10 is arranged on the upper left side of the partition, and the second corridor 10 and the second corridor 10 are arranged on the upper left side of the partition. The detection port between the three corridors 11 is set on the right side of the upper part of the partition, so that the sewage in the reaction box flows through each corridor in an S-shape, which can not only fully react the sewage, but also save land occupation.

In this embodiment, the reaction box can be made of metal materials such as stainless steel or carbon steel, which has high strength and corrosion resistance, and the upper end of the box is covered to prevent microwave leakage.

In this embodiment, the power used by the microwave generator is 400-2000W/ton of water, and the microwave power and hydraulic retention time are adjusted according to the water quality.

The working principle of the novel photocatalytic sewage treatment equipment based on microwave irradiation provided in this example is as follows:

Sewage enters the reactor from the water inlet pipe 8 at the lower part of the first corridor 9 and contacts the catalyst plate 4. Under the irradiation of ultraviolet light, electron-hole pairs are generated on the surface of the _TiO2 photocatalyst, and the electron-hole pairs have a strong capture of electrons. It can take away the electron e ^- of water or organic matter, thereby generating strong oxidizing substance ·OH, which undergoes oxidative degradation reaction with organic pollutants in water. Microwave irradiation can accelerate the generation of electron-hole pairs and inhibit their recombination, thereby generating more OH oxidation degradation pollutants. At the same time, microwave irradiation can generate a microwave field in the reactor, and the non-thermal effect of microwave exerts an effect on the chemical bonds of organic matter to achieve the effect of breaking rings and breaking bonds and improving biochemical properties. Microwave irradiation has a certain decolorization effect on sewage, can improve the transparency of sewage, enhance the permeability of ultraviolet light, and is beneficial to the photocatalytic reaction. The reaction device is continuously aerated to increase the agitation of the water flow. Sewage flows through the corridors in turn, and flows out from the outlet pipe 12 after multi-stage treatment.

Utilize the novel photocatalytic sewage treatment equipment based on microwave irradiation in this embodiment to treat the sewage produced by a certain chemical plant. The main pollutant of the sewage is the difficult biodegradable substance tetrahydrofuran, the COD is about 3000mg/L, the total salt is 1000mg/L, and the pH is neutral. Design a microwave photocatalytic wastewater treatment reaction device, with three corridors in total, each corridor is 1m long, 0.3m wide, and 0.6m high, and each corridor is equipped with a detection port. The microwave power is set to 450W, and the ultraviolet light intensity is 300μW/cm ² . The reaction time is 4 hours, the COD removal rate of effluent is 56%, and the B/C ratio is 0.42. In the absence of microwave irradiation, the removal rate of COD by simple photocatalytic oxidation is only 32%, and the B/C ratio is 0.27. It can be seen that increasing the microwave irradiation in the photocatalytic reaction can increase the removal efficiency of pollutants and improve the biochemical properties of wastewater.

Example 2

In a typical implementation of the present invention, a novel photocatalytic sewage treatment process based on microwave irradiation is proposed, including: sewage enters the interior of the reaction box, and the sewage is treated by utilizing the synergistic effect of microwave irradiation and photocatalysis .

This process introduces microwave irradiation into the photocatalytic wastewater treatment system. Compared with single photocatalytic technology, the microwave effect can generate e ^- or h ⁺ capture centers, inhibit the recombination of e ^- /h ⁺ in photocatalysis, and benefit the free state. The generation of OH, thereby increasing the efficiency of wastewater treatment and increasing the reaction rate. At the same time, microwave irradiation has a better decolorization effect, which can prevent the photocatalytic reaction from being limited by the chromaticity of water.

The embodiments described above have described the technical solutions 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. All done within the principle scope of the present invention Any modification, supplement or substitution in a similar manner shall be included within the protection scope of the present invention.

Claims (10)

1. A novel photocatalysis sewage treatment device based on microwave irradiation is characterized by comprising a reaction box body, wherein a plurality of galleries are arranged in the reaction box body, two adjacent galleries are separated by a partition plate and are mutually communicated through a detection port, a plurality of catalyst polar plates and ultraviolet lamp tubes are arranged in each gallery, and the catalyst polar plates and the ultraviolet lamp tubes are arranged at intervals; and a microwave transmitting antenna is arranged at the central position of each gallery, and the axis of the microwave transmitting antenna is vertical to the catalyst polar plate.

2. The novel photocatalytic wastewater treatment device based on microwave irradiation as set forth in claim 1, wherein the galleries are provided in three, including a first gallery, a second gallery and a third gallery.

3. The novel photocatalytic sewage treatment device based on microwave irradiation in claim 2 is characterized in that the lower part of the first gallery is provided with a water inlet which is connected with a water inlet pipe.

4. The novel photocatalytic sewage treatment equipment based on microwave irradiation as set forth in claim 2, wherein the top of the third gallery is provided with a temperature sensor, the temperature sensor is inserted into the box body, and a water outlet is arranged above the side wall of the third gallery and connected with a water outlet pipe.

5. The novel photocatalytic sewage treatment equipment based on microwave irradiation as set forth in claim 1, wherein each of the galleries is provided with an aeration inlet at the lower part, and the aeration inlet is connected with an aeration pipe and an aeration fan in sequence.

6. The microwave irradiation-based novel photocatalytic sewage treatment device as claimed in claim 1, wherein the catalyst electrode plates and the ultraviolet lamp tubes are arranged in parallel at intervals, two ultraviolet lamp tubes are arranged between two adjacent catalyst electrode plates, and a certain distance is reserved between the two ultraviolet lamp tubes.

7. The microwave irradiation-based photocatalytic sewage treatment device as claimed in claim 6, wherein the microwave transmitting antenna is located between two ultraviolet lamps and passes through the catalyst plate.

8. The novel photocatalytic sewage treatment equipment based on microwave irradiation as set forth in claim 1, wherein the microwave transmitting antenna is connected with a microwave generator, and the microwave generator is arranged outside the reaction tank body.

9. The novel photocatalytic sewage treatment device based on microwave irradiation as set forth in claim 1, wherein the detection port is provided at an upper portion of the partition plate.

10. A novel photocatalysis sewage treatment process based on microwave irradiation is realized by adopting the process as claimed in any one of claims 1 to 9, and is characterized in that sewage enters the interior of a reaction box body and is treated by utilizing the synergistic effect of the microwave irradiation and photocatalysis.

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