Sewage treatment reactor based on microwave electrodeless ultraviolet rays and advanced oxidation method

Abstract

The invention discloses a sewage treatment reactor based on microwave electrodeless ultraviolet rays and an advanced oxidation method, relates to the technical field of sewage treatment, and aims to solve the problem of how to improve the distribution uniformity of a light field in the reactor so as to enhance the activation efficiency of ultraviolet rays on an oxidant. According to the reactor, at least two light source groups are arranged on a reactor main body, the head-to-tail directions of any two adjacent microwave electrodeless ultraviolet light sources in each light source group are opposite, and the head-to-tail directions of the microwave electrodeless ultraviolet light sources in the same arrangement in the two adjacent light source groups are opposite; therefore, the strong light field areas and the weak light field areas of the plurality of microwave electrodeless ultraviolet light sources are alternately complemented in space, and the distribution uniformity of ultraviolet light fields in the reaction cavity is effectively improved, so that the utilization rate of ultraviolet light is improved, the activation efficiency of the ultraviolet light on an oxidant is enhanced, and the sewage oxidation treatment effect of the reactor is finally improved.

Description

Technical Field

[0001] This invention belongs to the field of wastewater treatment technology, specifically relating to a wastewater treatment reactor and an advanced oxidation method based on microwave electrodeless ultraviolet light. Background Technology

[0002] In recent years, research on emerging pollutants has attracted significant attention. Emerging pollutants refer to a class of chemical substances that are detectable in the environment and natural ecosystems and can pose significant risks and hazards to human health and environmental safety even at low doses. Emerging pollutants have a wide range of sources, are diverse, and are difficult to effectively degrade using traditional water treatment processes. Residual emerging pollutants entering water bodies can cause serious harm to human health and the natural environment.

[0003] Advanced oxidation processes utilize highly oxidizing free radicals to effectively oxidize and degrade new pollutants, thus achieving efficient wastewater treatment. However, oxidants require activation to enhance their oxidation effect. Common activation methods include adding external energy and adding chemical activators. Adding chemical agents for activation may cause secondary pollution; ultraviolet light, as a physical activation method, effectively avoids this problem. Microwave electrodeless ultraviolet lamps use microwaves to excite a filling gas to generate ultraviolet light. Compared to traditional electrodeless ultraviolet lamps, they do not have electrode aging issues, have a longer lifespan, and a more stable light source. They can effectively activate oxidants such as hydrogen peroxide to generate free radicals, thereby achieving efficient pollutant degradation.

[0004] Existing wastewater treatment reactors that utilize ultraviolet light as an activation method and employ microwave electrodeless ultraviolet lamps as the ultraviolet light source neglect the characteristic that the light intensity gradually decreases along the direction of the lamp tube. Specifically, microwave electrodeless ultraviolet lamps have a strong light field region near the microwave source (e.g., Figure 6 As shown in the diagram, the multiple microwave electrodeless ultraviolet lamps in the reactor, arranged in the same direction, result in uneven light field distribution, leading to low ultraviolet utilization, reduced oxidant activation effect, and increased energy consumption. Furthermore, existing advanced ultraviolet oxidation processes for wastewater treatment often involve mixing the oxidant with the wastewater before introducing it into the reactor for reaction. However, when pollutants in the wastewater react with the oxidant to form substances that absorb ultraviolet light, the penetration rate of ultraviolet light in the water is often reduced, thus failing to effectively activate the oxidant and affecting the wastewater oxidation treatment effect.

[0005] Therefore, a major challenge in treating wastewater containing new pollutants using advanced oxidation processes is how to improve the activation efficiency of the oxidant. To address this, it is necessary to improve existing wastewater treatment reactors to enhance the activation efficiency of the oxidant by ultraviolet light during water oxidation, thereby improving the oxidation effect. Summary of the Invention

[0006] This invention provides a wastewater treatment reactor based on microwave electrodeless ultraviolet light, aiming to solve the problem of how to improve the uniformity of light field distribution within the reactor in order to enhance the activation efficiency of ultraviolet light on oxidants.

[0007] The technical solution adopted by the present invention to solve its technical problem is: a wastewater treatment reactor based on microwave electrodeless ultraviolet light, comprising a reactor body and a microwave electrodeless ultraviolet light source;

[0008] The reactor body has a reaction chamber, and the reactor body is provided with an inlet that communicates with the bottom of the reaction chamber and an outlet that communicates with the top of the reaction chamber.

[0009] The microwave electrodeless ultraviolet light source is mounted on the reactor body and passes through the reaction chamber;

[0010] The reactor body is provided with at least two light source groups that are spaced apart along a first direction, and the light source groups are composed of at least two microwave electrodeless ultraviolet light sources that are spaced apart along a second direction.

[0011] In each light source group, the start and end directions of any two adjacent microwave electrodeless ultraviolet light sources are opposite, and the start and end directions of microwave electrodeless ultraviolet light sources with the same position in any two adjacent light source groups are opposite.

[0012] Wherein, the first direction and the second direction are perpendicular to each other.

[0013] Furthermore, the microwave electrodeless ultraviolet light sources in any two adjacent light source groups are staggered in the first direction.

[0014] Furthermore, the microwave electrodeless ultraviolet light source passes through the reaction chamber along the crossflow direction, which is perpendicular to the mainstream direction of the wastewater in the reaction chamber.

[0015] Furthermore, the microwave electrodeless ultraviolet light source includes a quartz sleeve that at least partially passes through the reaction chamber, a metal mesh cover disposed inside the quartz sleeve, a microwave electrodeless ultraviolet lamp disposed inside the metal mesh cover, and a microwave generator connected to the metal mesh cover via a waveguide.

[0016] Furthermore, the reactor body is provided with an air inlet connected to the bottom of the reaction chamber and an air outlet connected to the top of the reaction chamber.

[0017] The microwave electrodeless ultraviolet light source includes a wind-cooling device, and the air outlet of the wind-cooling device is connected to the first end of the quartz sleeve.

[0018] The reactor also includes an aeration device, which includes an air supply pipe, an aeration fan and a gas flow meter installed on the air supply pipe; the air inlet of the air supply pipe is connected to the tail end of each quartz sleeve, and the air outlet of the air supply pipe is connected to the air inlet.

[0019] Furthermore, the microwave electrodeless ultraviolet lamp is a 254 nm single-wavelength electrodeless ultraviolet lamp or a 185 / 254 nm dual-wavelength electrodeless ultraviolet lamp;

[0020] When the microwave electrodeless ultraviolet lamp is a 185 / 254 nm dual-wavelength electrodeless ultraviolet lamp, the reactor also includes an ozone collection device connected to the gas outlet.

[0021] Furthermore, the reactor body is provided with a dosing port that corresponds one-to-one with the head end of the microwave electrodeless ultraviolet light source, and the dosing port is connected to the reaction chamber;

[0022] The reactor also includes a dosing device, which includes a dosing tank, a drug delivery pipe, and a dosing pump; the inlet of the drug delivery pipe is connected to the dosing tank, and the outlet of the drug delivery pipe is connected to each dosing port; the dosing pump is installed on the drug delivery pipe.

[0023] The present invention also provides an advanced oxidation method based on microwave electrodeless ultraviolet light, which uses the above-mentioned wastewater treatment reactor based on microwave electrodeless ultraviolet light to treat wastewater.

[0024] This invention also provides an advanced oxidation method based on microwave electrodeless ultraviolet light, which uses the aforementioned microwave electrodeless ultraviolet light-based wastewater treatment reactor to treat wastewater and performs the following controls:

[0025] The residence time of wastewater in the reaction chamber is controlled to be 30–60 s;

[0026] And / or, control the aeration device to ensure that the gas flow rate entering the reaction chamber is 0.01–0.1 m³. 3 / s;

[0027] And / or, control the dosing device to make the concentration of oxidant in the wastewater in the reaction chamber 1-10 mg / L.

[0028] Furthermore, the oxidant is one of hydrogen peroxide, persulfate, periodate, potassium permanganate, peracetic acid, and sodium hypochlorite.

[0029] The beneficial effects of this invention are as follows:

[0030] 1) By setting at least two light source groups on the reactor body, and making the head and tail directions of any two adjacent microwave electrodeless ultraviolet light sources in each light source group opposite, and the head and tail directions of microwave electrodeless ultraviolet light sources with the same position in two adjacent light source groups opposite, the strong light field region and the weak light field region of multiple microwave electrodeless ultraviolet light sources are spatially alternated and complemented, which effectively improves the uniformity of ultraviolet light field distribution in the reaction chamber, thereby improving the utilization rate of ultraviolet light, enhancing the activation efficiency of ultraviolet light on oxidant, and ultimately improving the wastewater oxidation treatment effect of the reactor.

[0031] 2) By staggering the distribution of microwave electrodeless ultraviolet light sources in any two adjacent light source groups in the first direction, the turbulence of wastewater in the reactor can be increased, which is conducive to the full mixing and contact of wastewater and oxidant, and further improves the wastewater oxidation treatment effect.

[0032] 3) The aeration device can collect and transport air-cooled gas into the reaction chamber to agitate the wastewater, further increasing the turbulence of the wastewater in the reactor.

[0033] 4) When using 185 / 254 nm dual-wavelength electrodeless ultraviolet lamps as microwave electrodeless ultraviolet lamps, a multi-synergistic oxidation system of ultraviolet light / oxidant / ozone can be formed, which can improve the oxidation and removal effect of pollutants.

[0034] 5) By opening dosing ports on the reactor body that correspond one-to-one with the heads of the microwave electrodeless ultraviolet light source, and connecting the dosing devices to the dosing ports, it can be ensured that the oxidant is added at a location with strong ultraviolet light intensity, so as to facilitate the oxidant to fully absorb ultraviolet light, enhance the activation effect, improve the free radical yield, and thus further improve the oxidation and removal effect of pollutants.

[0035] The technical effects brought about or directly generated by other technical features of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0036] Figure 1 This is a three-dimensional structural schematic diagram of the reactor in this invention;

[0037] Figure 2 This is a three-dimensional structural schematic diagram of the microwave electrodeless ultraviolet light source in this invention;

[0038] Figure 3 This is a schematic diagram of another embodiment of the reactor of the present invention;

[0039] Figure 4 This is a schematic diagram of another embodiment of the reactor of the present invention;

[0040] Figure 5 This is a schematic diagram of another embodiment of the reactor of the present invention;

[0041] Figure 6 This is a diagram showing the light field distribution characteristics of a microwave electrodeless ultraviolet light source;

[0042] Figure 7 These are the electron paramagnetic resonance spectroscopy test results of water samples from Example 2 and Comparative Example 1;

[0043] The diagram is labeled as follows: 100-reactor body, 101-reaction chamber, 110-water inlet, 120-water outlet, 130-air inlet, 140-air outlet, 150-dosing port, 200-microwave electrodeless ultraviolet light source, 210-quartz sleeve, 220-metal mesh cover, 230-microwave electrodeless ultraviolet lamp tube, 240-microwave generator, 250-waveguide, 260-air cooling device, 310-air supply pipe, 320-aeration blower, 330-gas flow meter, 400-ozone collection device, 510-dosing tank, 520-drug delivery pipe, 530-dosing pump. Detailed Implementation

[0044] The present invention will be further described below with reference to the accompanying drawings and embodiments. The same reference numerals in the drawings denote components with the same or similar functions. Although various aspects of the embodiments are shown in the drawings, they are not necessarily drawn to scale unless specifically indicated otherwise.

[0045] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "head," "tail," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or position and dimensional relationship based on the orientation or position relationship shown in the accompanying drawings. They are only for the convenience of description and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0046] When the term "many" indicates a quantity, it usually refers to three or more. For example, "multiple" typically means three or more. The term "and / or" merely describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A alone, A and B simultaneously, or B alone. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be interpreted as indicating or implying relative importance.

[0047] Combination Figure 1 and Figure 2 As shown, the wastewater treatment reactor based on microwave electrodeless ultraviolet light includes a reactor body 100 and a microwave electrodeless ultraviolet light source 200.

[0048] The reactor body 100 has a reaction chamber 101. The reactor body 100 is provided with an inlet 110 that communicates with the bottom of the reaction chamber 101 and an outlet 120 that communicates with the top of the reaction chamber 101. The reactor body 100 is mainly used to provide reaction space for wastewater oxidation treatment. It can be a cuboid, tubular, columnar or other structures, preferably a cylindrical tank with upper and lower end caps.

[0049] A microwave electrodeless ultraviolet light source 200 is mounted on the reactor body 100 and passes through the reaction chamber 101; typically, the end of the microwave electrodeless ultraviolet light source 200 closest to the microwave source is considered the beginning end, and the end furthest from the microwave source is considered the end. Figure 6 As shown, the microwave electrodeless ultraviolet light source 200 forms a strong light field region near the front end and a weak light field region near the rear end.

[0050] The reactor body 100 is provided with at least two light source groups that are spaced apart along a first direction. Each light source group consists of at least two microwave electrodeless ultraviolet light sources 200 that are spaced apart along a second direction. The first direction is usually the height direction of the reaction chamber 101 or the mainstream direction of the wastewater in the reaction chamber 101.

[0051] In each light source group, the head and tail directions of any two adjacent microwave electrodeless ultraviolet light sources 200 are opposite, and the head and tail directions of microwave electrodeless ultraviolet light sources 200 with the same position in any two adjacent light source groups are opposite; that is, by installing two adjacent microwave electrodeless ultraviolet light sources 200 on the reactor body 100 in opposite directions, the strong light field region and the weak light field region of multiple microwave electrodeless ultraviolet light sources 200 are spatially alternately complementary.

[0052] The first direction and the second direction are perpendicular to each other.

[0053] This reactor effectively improves the uniformity of the ultraviolet light field distribution in the reaction chamber 101, increases the utilization rate of ultraviolet light, enhances the activation efficiency of ultraviolet light on oxidants, and ultimately improves the wastewater oxidation treatment effect of the reactor.

[0054] Combination Figure 1 and Figure 4 As shown, in some embodiments, the microwave electrodeless ultraviolet light sources 200 in any two adjacent light source groups are staggered in the first direction, so that the microwave electrodeless ultraviolet light sources 200 form a certain obstruction downstream of the sewage flow path, thereby disturbing the water flow and increasing the turbulence of the sewage in the reactor, which is conducive to the full mixing and contact of sewage and oxidant, and further improves the sewage oxidation treatment effect.

[0055] In some embodiments, the microwave electrodeless ultraviolet light source 200 passes through the reaction chamber 101 in a crossflow direction, which is perpendicular to the mainstream direction of the wastewater in the reaction chamber 101. In this way, the microwave electrodeless ultraviolet light source 200 can effectively exert a turbulence effect while making the distribution of ultraviolet rays in the water body cross section more uniform, thereby maximizing the contact efficiency between ultraviolet rays and wastewater.

[0056] Preferably, each microwave electrodeless ultraviolet light source 200 is parallel to each other, and the distance between any two adjacent microwave electrodeless ultraviolet light sources 200 is 15-25 cm, so as to ensure the ultraviolet intensity at all points of the reaction chamber 101, so that the reactor has a good wastewater oxidation treatment effect.

[0057] Specifically, and then combined Figure 1 and Figure 2 As shown, the microwave electrodeless ultraviolet light source 200 includes a quartz sleeve 210 that at least partially passes through the reaction chamber 101, a metal mesh cover 220 disposed within the quartz sleeve 210, a microwave electrodeless ultraviolet lamp 230 disposed within the metal mesh cover 220, and a microwave generator 240 connected to the metal mesh cover 220 via a waveguide 250.

[0058] Preferably, the distance between the outer wall of the metal mesh cover 220 and the inner wall of the quartz sleeve 210 is 1 to 15 mm.

[0059] Combination Figure 1 , Figure 2 and Figure 3 As shown, in some embodiments, the reactor body 100 is provided with an air inlet 130 connected to the bottom of the reaction chamber 101 and an air outlet 140 connected to the top of the reaction chamber 101; the microwave electrodeless ultraviolet light source 200 includes an air-cooling device 260, the air outlet of which is connected to the first end of the quartz sleeve 210; the reactor also includes an aeration device, which includes an air supply pipe 310, an aeration blower 320 and a gas flow meter 330 installed on the air supply pipe 310; the air inlet of the air supply pipe 310 is connected to the tail end of each quartz sleeve 210, and the air outlet of the air supply pipe 310 is connected to the air inlet 130. The aeration device can collect and transport air-cooled gas into the reaction chamber 101 to agitate the wastewater, further increasing the turbulence of the wastewater in the reactor, which is beneficial for the thorough mixing and contact of the wastewater and the oxidant, further improving the wastewater oxidation treatment effect.

[0060] Preferably, the microwave electrodeless ultraviolet lamp 230 is a 254 nm single-wavelength electrodeless ultraviolet lamp or a 185 / 254 nm dual-wavelength electrodeless ultraviolet lamp.

[0061] When the 230 microwave electrodeless ultraviolet lamp is a dual-wavelength electrodeless ultraviolet lamp at 185 / 254 nm, it can form a multi-synergistic oxidation system of ultraviolet light, oxidant, and ozone, improving the oxidation and removal efficiency of pollutants. To avoid environmental pollution from the generated ozone, such as... Figure 4 As shown, in some embodiments, the reactor also includes an ozone collection device 400 connected to the outlet 140 to absorb excess ozone.

[0062] like Figure 5 As shown, in some embodiments, the reactor body 100 is provided with dosing ports 150 corresponding one-to-one with the heads of the microwave electrodeless ultraviolet light source 200, and the dosing ports 150 are connected to the reaction chamber 101. The reactor also includes a dosing device, which includes a dosing tank 510, a drug delivery pipe 520, and a dosing pump 530. The inlet of the drug delivery pipe 520 is connected to the dosing tank 510, and the outlet of the drug delivery pipe 520 is connected to each dosing port 150. The dosing pump 530 is installed on the drug delivery pipe 520. In this way, the oxidant can be added at a location with strong ultraviolet light intensity, so as to facilitate the oxidant to fully absorb ultraviolet light, enhance the activation effect, improve the free radical yield, and thus further improve the oxidation and removal effect of pollutants.

[0063] The present invention also provides an advanced oxidation method based on microwave electrodeless ultraviolet light, which uses the above-mentioned wastewater treatment reactor based on microwave electrodeless ultraviolet light to treat wastewater.

[0064] In some embodiments, the specific steps of the above-mentioned advanced oxidation method are as follows: The air-cooling device 260 and the microwave generator 240 are turned on to excite the microwave electrodeless ultraviolet light source 200 to generate ultraviolet light. The oxidant stored in the dosing tank 510 is pumped into the reaction chamber 101 through the dosing pump 530 from each dosing port 150, and the ultraviolet light is used to activate the oxidant to generate free radicals. The wastewater to be treated is introduced into the reaction chamber 101 through the inlet 110 for continuous oxidation treatment, and then discharged through the outlet 120. Air-cooled gas is collected and sent to the air inlet 130 through the aeration blower 320, entering the reaction chamber 101 to agitate the water and increase its turbulence. The gas flow rate entering the reaction chamber 101 is controlled by the gas flow meter 330, and the aerated gas is discharged through the outlet 140.

[0065] Preferably, the above-described advanced oxidation method further includes the following controls:

[0066] The residence time of wastewater in reaction chamber 101 is controlled to be 30–60 s;

[0067] And / or, control the aeration device to make the gas flow rate entering the reaction chamber 101 0.01 to 0.1 m³ / s. 3 / s;

[0068] And / or, control the dosing device to make the concentration of oxidant in the wastewater in the reaction chamber 101 1-10 mg / L.

[0069] The oxidant can be water treatment oxidants such as hydrogen peroxide, persulfate, periodate, potassium permanganate, peracetic acid, and sodium hypochlorite.

[0070] Example 1

[0071] Combination Figure 1 , Figure 2 and Figure 5 As shown, the wastewater treatment reactor based on microwave electrodeless ultraviolet light includes a reactor body 100 and a microwave electrodeless ultraviolet light source 200.

[0072] The reactor body 100 has a reaction chamber 101, and the reactor body 100 is provided with an inlet 110 that communicates with the bottom of the reaction chamber 101 and an outlet 120 that communicates with the top of the reaction chamber 101.

[0073] A microwave electrodeless ultraviolet light source 200 is disposed on the reactor body 100 and passes through the reaction chamber 101 from the front and back direction of the reactor body 100;

[0074] The reactor body 100 is provided with four light source groups that are spaced apart along a first direction. Each light source group consists of three microwave electrodeless ultraviolet light sources 200 that are spaced apart along a second direction. The first direction is the height direction of the reaction chamber 101, and the second direction is the left-right direction of the reactor body 100.

[0075] Following the order from bottom to top and from left to right in the reaction chamber 101, the microwave electrodeless ultraviolet light sources 200 are numbered L. ij Where i represents its row number and j represents its column number; for any L ij Microwave electrodeless ultraviolet light source 200 and L i,j+1 200 microwave electrodeless ultraviolet light source and any L ij Microwave electrodeless ultraviolet light source 200 and L i+1,j The microwave electrodeless ultraviolet light source 200 is installed on the reactor body 100 in opposite directions, that is, the two adjacent microwave electrodeless ultraviolet light sources 200 are in opposite directions, so that the strong light field region and the weak light field region of the multiple microwave electrodeless ultraviolet light sources 200 are spatially alternately complementary.

[0076] At the same time, for any L ij Microwave electrodeless ultraviolet light source 200 and L i,j+1 200 microwave electrodeless ultraviolet light source, L i+1,j Microwave electrodeless ultraviolet light source 200 is set at L ij Microwave electrodeless ultraviolet light source 200 and L i,j+1Above the gaps between the microwave electrodeless ultraviolet light sources 200, the microwave electrodeless ultraviolet light sources 200 in different rows are arranged in an alternating pattern to increase the turbulence of the water flow in the reaction chamber 101.

[0077] Example 2

[0078] The wastewater treatment reactor based on microwave electrodeless ultraviolet light provided by this invention is used, with a 254 nm single-wavelength electrodeless ultraviolet lamp as the microwave electrodeless ultraviolet light source 200. Microwave electrodeless ultraviolet light is used to activate hydrogen peroxide to remove ciprofloxacin (3.6 μg / L) from the wastewater. The specific operation is as follows: The air-cooling device 260 and microwave generator 240 are turned on to excite the microwave electrodeless ultraviolet light source 200 to generate ultraviolet light. The dosing pump 530 is turned on, and the hydrogen peroxide stock solution (mass fraction of 30%) in the dosing tank 510 is pumped into the reaction chamber 101 through each dosing port 150. The dosage is controlled at 0.02 mL of hydrogen peroxide stock solution per liter of wastewater, so that the oxidant concentration in the wastewater reaches 5 mg / L, and the hydrogen peroxide is activated by ultraviolet light to generate free radicals. The wastewater to be treated is introduced into the reaction chamber 101 through the inlet 110 for continuous oxidation treatment. The hydraulic retention time is controlled at 60 s, and the treated water is discharged through the outlet 120. Turn on the aeration blower 320 to collect air-cooled gas and send it into the air inlet 130, where it enters the reaction chamber 101 to agitate the water and increase its turbulence. The gas flow rate entering the reaction chamber 101 is controlled to be 0.1 m³ / s by the gas flow meter 330. 3 / s, the gas is discharged through the outlet 140.

[0079] After testing, the removal rate of ciprofloxacin in the wastewater was 69.8%, and hydrogen peroxide was not detected in the effluent.

[0080] Comparative Example 1

[0081] In this comparative example, the removal of ciprofloxacin (3.6 μg / L) from wastewater by microwave electrodeless ultraviolet activation of hydrogen peroxide was also carried out. The operation of this comparative example was basically the same as that of Example 2, except that the hydrogen peroxide was mixed with the wastewater before entering the reaction chamber 101 and then treated with ultraviolet light.

[0082] After testing, the removal rate of ciprofloxacin in the wastewater was 51.4%, and the concentration of hydrogen peroxide in the effluent was 0.1 mg / L.

[0083] Combination Figure 7As shown, Comparative Example 1, which involved mixing wastewater with hydrogen peroxide before ultraviolet irradiation, showed a lower removal efficiency of ciprofloxacin compared to Example 2. This is mainly because the existing pollutants in the wastewater of Comparative Example 1, as well as the degradation products generated after mixing the wastewater with hydrogen peroxide, reduced the penetration rate of ultraviolet light, thereby weakening the activation effect of hydrogen peroxide and resulting in a lower degradation effect of ciprofloxacin. In Example 2, hydrogen peroxide was added in a strong ultraviolet region through dosing port 150, which increased the yield of hydroxyl radicals and thus improved the removal efficiency of ciprofloxacin.

[0084] Example 3

[0085] The wastewater treatment reactor based on microwave electrodeless ultraviolet light provided by this invention was used to remove ibuprofen (22.7 μg / L) from wastewater by activating hydrogen peroxide with microwave electrodeless ultraviolet light. The specific operation was basically the same as in Example 2, with the hydraulic retention time controlled at 60 s. The only difference was that the dosage of 30% hydrogen peroxide stock solution was controlled at 0.03 mL per liter of wastewater, and the gas flow rate was controlled at 0.01 m³ / L. 3 / s.

[0086] After testing, the removal rate of ibuprofen in the wastewater was 89.4%.

[0087] Comparative Example 2

[0088] In this comparative example, the removal of ibuprofen (22.7 μg / L) from wastewater by microwave electrodeless ultraviolet activation of hydrogen peroxide is also performed. The operation of this comparative example is basically the same as that of Example 3, except that the microwave electrodeless ultraviolet light sources 200 on the reactor body 100 are all installed in the same direction, that is, during the wastewater oxidation process, the strong light field area of ​​the microwave electrodeless ultraviolet light source 200 is concentrated on one side of the reaction chamber 101.

[0089] After testing, the removal rate of ibuprofen in the wastewater was 74.2%.

[0090] Combining Example 3 and Comparative Example 2, the ibuprofen removal effect of the reactor in Comparative Example 2, which used a microwave electrodeless ultraviolet light source 200 placed on the same side, was lower than that in Example 3. This is mainly because the ultraviolet light intensity of the microwave electrodeless ultraviolet light source 200 gradually decreases from the beginning to the end of the lamp tube, with lower light intensity at the end. This results in an uneven distribution of the ultraviolet light field in Comparative Example 2, reducing the activation effect of the hydrogen peroxide added from the dosing port 150, leading to a lower ibuprofen removal effect. In Example 3, the ultraviolet light field distribution was more uniform, and the added hydrogen peroxide was activated near the strong light field area, increasing the yield of hydroxyl radicals and thus improving the ibuprofen removal effect.

[0091] Example 4

[0092] The wastewater treatment reactor based on microwave electrodeless ultraviolet light provided by this invention was used to remove nitrobenzene (1.1 μg / L) from wastewater by activating hydrogen peroxide with microwave electrodeless ultraviolet light. The specific operation was basically the same as in Example 2, with the dosage of 30% hydrogen peroxide stock solution controlled at 0.02 mL per liter of wastewater and the gas flow rate controlled at 0.1 m³ / L. 3 The only difference is that a 185 / 254 nm dual-wavelength electrodeless ultraviolet lamp is used as the microwave electrodeless ultraviolet light source 200, and an ozone collection device 400 is set at the gas outlet to control the hydraulic residence time to 30 s.

[0093] After testing, the removal rate of nitrobenzene in the wastewater was 88.6%.

[0094] Comparative Example 3

[0095] In this comparative example, the removal of nitrobenzene (1.1 μg / L) from wastewater by microwave electrodeless ultraviolet activation of hydrogen peroxide is also performed. The operation of this comparative example is basically the same as that of Example 4, except that a 254 nm single-wavelength electrodeless ultraviolet lamp is used as the microwave electrodeless ultraviolet light source 200.

[0096] After testing, the removal rate of nitrobenzene in the wastewater was 62.1%.

[0097] Combining Example 4 and Comparative Example 3, Example 4, using a 185 / 254 nm dual-wavelength microwave electrodeless ultraviolet lamp, showed a higher treatment effect on nitrobenzene than Comparative Example 3. This is mainly because the 185 / 254 nm dual-wavelength electrodeless ultraviolet lamp used in Example 4 can excite the air to generate ozone. The ozone in the recirculated gas enters the reactor, which can both agitate the liquid and form a multi-synergistic oxidation system of ultraviolet light / hydrogen peroxide / ozone to react with nitrobenzene, thereby improving the removal efficiency of nitrobenzene.

[0098] This document presents a description of various embodiments of the invention for illustrative purposes only and is not intended to be exhaustive or limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A wastewater treatment reactor based on microwave electrodeless ultraviolet light, comprising a reactor body (100) and a microwave electrodeless ultraviolet light source (200). The reactor body (100) has a reaction chamber (101), and the reactor body (100) is provided with an inlet (110) connected to the bottom of the reaction chamber (101) and an outlet (120) connected to the top of the reaction chamber (101). The microwave electrodeless ultraviolet light source (200) is set on the reactor body (100) and passes through the reaction chamber (101). Its features are: The reactor body (100) is provided with at least two light source groups that are spaced apart along a first direction, and the light source groups are composed of at least two microwave electrodeless ultraviolet light sources (200) that are spaced apart along a second direction. In each light source group, the head and tail directions of any two adjacent microwave electrodeless ultraviolet light sources (200) are opposite, and the head and tail directions of any two adjacent microwave electrodeless ultraviolet light sources (200) with the same position in any two light source groups are opposite. Wherein, the first direction and the second direction are perpendicular to each other.

2. The wastewater treatment reactor based on microwave electrodeless ultraviolet light according to claim 1, characterized in that: The microwave electrodeless ultraviolet light sources (200) in any two adjacent light source groups are staggered in the first direction.

3. The wastewater treatment reactor based on microwave electrodeless ultraviolet light according to claim 2, characterized in that: The microwave electrodeless ultraviolet light source (200) passes through the reaction chamber (101) in a crossflow direction, which is perpendicular to the mainstream direction of the sewage in the reaction chamber (101).

4. The wastewater treatment reactor based on microwave electrodeless ultraviolet light according to any one of claims 1 to 3, characterized in that: The microwave electrodeless ultraviolet light source (200) includes a quartz sleeve (210) that at least partially passes through the reaction chamber (101), a metal mesh cover (220) disposed inside the quartz sleeve (210), a microwave electrodeless ultraviolet lamp (230) disposed inside the metal mesh cover (220), and a microwave generator (240) connected to the metal mesh cover (220) via a waveguide (250).

5. The wastewater treatment reactor based on microwave electrodeless ultraviolet light according to claim 4, characterized in that: The reactor body (100) is provided with an air inlet (130) that communicates with the bottom of the reaction chamber (101) and an air outlet (140) that communicates with the top of the reaction chamber (101). The microwave stepless ultraviolet light source (200) includes a wind-cooling device (260), the air outlet of which is connected to the first end of the quartz sleeve (210); The reactor also includes an aeration device, which includes an air supply pipe (310), an aeration blower (320) and a gas flow meter (330) installed on the air supply pipe (310); the air inlet of the air supply pipe (310) is connected to the tail end of each quartz sleeve (210), and the air outlet of the air supply pipe (310) is connected to the air inlet (130).

6. The wastewater treatment reactor based on microwave electrodeless ultraviolet light according to claim 5, characterized in that: The microwave electrodeless ultraviolet lamp (230) is a 254 nm single-wavelength electrodeless ultraviolet lamp or a 185 / 254 nm dual-wavelength electrodeless ultraviolet lamp; When the microwave electrodeless ultraviolet lamp (230) is a 185 / 254 nm dual-wavelength electrodeless ultraviolet lamp, the reactor also includes an ozone collection device (400) connected to the gas outlet (140).

7. The wastewater treatment reactor based on microwave electrodeless ultraviolet light according to claim 5, characterized in that: The reactor body (100) is provided with a dosing port (150) corresponding to the head end of the microwave electrodeless ultraviolet light source (200), and the dosing port (150) is connected to the reaction chamber (101); The reactor also includes a dosing device, which includes a dosing tank (510), a drug delivery pipe (520), and a dosing pump (530); the inlet of the drug delivery pipe (520) is connected to the dosing tank (510), and the outlet of the drug delivery pipe (520) is connected to each dosing port (150); the dosing pump (530) is installed on the drug delivery pipe (520).

8. An advanced oxidation method based on microwave electrodeless ultraviolet light, characterized in that: Wastewater is treated using the wastewater treatment reactor based on microwave electrodeless ultraviolet light as described in any one of claims 1 to 7.

9. An advanced oxidation method based on microwave electrodeless ultraviolet light, characterized in that, Wastewater is treated using the microwave electrodeless ultraviolet wastewater treatment reactor as described in claim 7, and the following controls are performed: The residence time of wastewater in the reaction chamber (101) is controlled to be 30–60 s; And / or, control the aeration device to make the gas flow rate entering the reaction chamber (101) 0.01–0.1 m³ / s. 3 / s; And / or, control the dosing device to make the concentration of oxidant in the wastewater in the reaction chamber (101) 1 to 10 mg / L.

10. The advanced oxidation method based on microwave electrodeless ultraviolet light according to claim 9, characterized in that: The oxidant is one of hydrogen peroxide, persulfate, periodate, potassium permanganate, peracetic acid, and sodium hypochlorite.

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