A double-layer liquid layer photocatalytic reactor

Abstract

The application discloses a double-layer liquid layer photocatalytic reactor, which comprises a circular tubular reactor with a cavity, the circular tubular reactor comprises a cylindrical ultraviolet lamp tube and two layers of annular liquid layers; wherein the cylindrical ultraviolet lamp tube is located at the center of the circular tubular reactor, one end of the ultraviolet lamp tube is connected with electricity, and the ultraviolet lamp tube can emit ultraviolet light to the surrounding; wherein the inner layer of the two layers of annular liquid layers is wrapped outside the cylindrical ultraviolet lamp tube, and the outer layer of the two layers of annular liquid layers is wrapped outside the inner layer; wherein the two sides of the inner layer and the outer layer of the two layers of annular liquid layers are respectively provided with water inlets and water outlets, the water inlet of the inner layer and the water outlet of the outer layer are located on the same side and are adjacently arranged, and the water outlet of the inner layer and the water inlet of the outer layer are located on the other side and are adjacently arranged.

Description

Technical Field

[0001] This utility model relates to photocatalytic equipment, specifically to a double-layer liquid-layer photocatalytic reactor. Background Technology

[0002] Photocatalytic oxidation is a common technology for treating high-concentration organic wastewater. It involves the reaction of ·OH radicals generated by an oxidant under ultraviolet light with organic matter, degrading and eventually mineralizing it. The reaction between ultraviolet light and the oxidant is approximately a zero-order reaction; the stronger the light intensity, the greater the amount of ·OH radicals produced. When the total organic matter (TOC) of the wastewater is greater than 100, TOC removal is approximately a first-order reaction. At this point, the generated ·OH radicals can rapidly combine with pollutants, so higher light intensity can significantly increase the reaction rate. However, when TOC is between 10 and 100, the collision probability between the ·OH radicals generated by photocatalytic oxidation and the pollutants is low due to the lower pollutant concentration. Increasing the light intensity in this case can easily lead to a waste of ultraviolet light and oxidant, increasing unnecessary costs. Therefore, reducing light intensity and extending the reaction time are commonly used methods for removing low-concentration TOC.

[0003] Photocatalytic reactors are typically single-layer reactors, meaning there is only a single annular layer of wastewater between the cylindrical UV lamp and the outer wall of the tubular reactor. During wastewater treatment, to maximize the utilization of light and oxidants, high-power UV lamps (1-20kW) are usually used to treat high-TOC wastewater (TOC > 100), with the liquid layer controlled within 1-2cm, coupled with a high water flow rate to achieve a vigorous photocatalytic reaction. In low-TOC wastewater (10 < TOC < 100), lower-power UV lamps (0.3-1kW) are used, with the liquid layer controlled above 2cm, or a multi-lamp system (multiple UV lamps within a single tubular reactor allow for a more uniform light intensity distribution, eliminating distinct high and low intensity zones), with a lower flow rate for a slower photocatalytic reaction.

[0004] In photocatalytic tubular reactors, a large liquid layer thickness can lead to problems such as turbulent flow, excessive circulation flow at high Reynolds numbers, large reactor footprint, and low utilization of internal space. Since high-power UV lamps typically penetrate more than 2 cm into wastewater, when using high-power UV lamps and controlling the liquid layer thickness to 1-2 cm, some UV light will penetrate the water layer without being absorbed by the wastewater. This portion of UV light intensity (such as UVC) is typically greater than 5 mW / cm². If this wasted UV light is applied to the removal of low-concentration TOC, the UV light utilization rate can be improved, significantly reducing the number of photoreactors required for low-concentration TOC treatment. Utility Model Content

[0005] The present invention aims to solve the problems mentioned in the background art.

[0006] This application discloses a bilayer liquid-layer photocatalytic reactor, comprising:

[0007] A cylindrical reactor with an internal cavity, the cylindrical reactor comprising a cylindrical ultraviolet lamp and two annular liquid layers;

[0008] The cylindrical ultraviolet lamp is located at the center of the cylindrical reactor, with one end of the ultraviolet lamp connected to electricity, and can emit ultraviolet light in all directions.

[0009] The inner layer of the two annular liquid layers wraps around the outside of the cylindrical ultraviolet lamp tube, and the outer layer of the two annular liquid layers wraps around the outside of the inner layer.

[0010] The inner and outer sides of the two annular liquid layers are respectively provided with inlets and outlets. The inlet of the inner layer and the outlet of the outer layer are on the same side and adjacent to each other, while the outlet of the inner layer and the inlet of the outer layer are on the other side and adjacent to each other.

[0011] In one specific embodiment, the two annular liquid layers are separated by quartz, with a thickness of 0.5-1 cm.

[0012] In one specific embodiment, the inner layer of the two annular liquid layers has a thickness of 1-2 cm, and the outer layer has a thickness of 2-5 cm.

[0013] In one specific embodiment, the outer wall of the cylindrical reactor is made of 304 stainless steel lined with polytetrafluoroethylene. Beneficial effects

[0014] 1. Using unabsorbed ultraviolet light from high-power ultraviolet lamps as a light source for treating wastewater with low TOC concentration can improve the utilization rate of ultraviolet light, reduce the number of photoreactors, and lower the operating cost of water treatment.

[0015] 2. The inner liquid layer is closer to the ultraviolet lamp and its temperature rises faster, while the temperature of the outer liquid layer is relatively lower. The water flow in the inner and outer liquid layers carries out convective heat exchange in opposite directions, which can keep the temperature of both liquid layers relatively constant.

[0016] 3. The two annular liquid layers are separated by quartz with 95% light transmittance, which reduces the loss of ultraviolet light without disrupting the flow pattern of the two wastewater layers. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of a double-layer liquid-layer photocatalytic reactor in this embodiment.

[0018] In the diagram: 1-UV lamp; 2-Inner annular liquid layer; 3-Outer annular liquid layer; 4-Quartz; 5-Circular reactor; 6-Inner inlet; 7-Outer outlet; 8-Inner outlet; 9-Outer inlet; 10-UV lamp power connection. Detailed Implementation

[0019] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0020] In the description of this utility model, it should be understood that the terms "center," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "counterclockwise," "clockwise," "axial," "radial," and "circumferential," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0021] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances. Example

[0022] See Figure 1This embodiment of a double-layer liquid-layer photocatalytic reactor includes a cylindrical reactor 5 with an internal cavity. The cylindrical reactor 5 includes a cylindrical ultraviolet lamp 1 and two annular liquid layers. The cylindrical ultraviolet lamp 1 is located at the center of the cylindrical reactor 5. One end of the ultraviolet lamp 1 is connected to electricity, and the connected end 10 of the ultraviolet lamp can emit ultraviolet light in all directions. The inner layer of the two annular liquid layers wraps around the outside of the cylindrical ultraviolet lamp 1, and the outer layer of the two annular liquid layers wraps around the outside of the inner layer. The inner layer inlet 6 and the outer layer outlet 7 are respectively provided on both sides of the inner and outer layers of the two annular liquid layers. The inner layer inlet 6 and the outer layer outlet 7 are arranged on the same side and adjacent to each other, and the inner layer outlet 8 and the outer layer inlet 9 are arranged on the other side and adjacent to each other.

[0023] The two annular liquid layers are separated by quartz 4 with a thickness of 0.5-1cm. By separating the two annular liquid layers with quartz 4, which has a light transmittance of 95%, the loss of ultraviolet light is reduced without disrupting the flow pattern of the two wastewater layers.

[0024] Specifically, the inner layer of the two annular liquid layers has a thickness of 1-2 cm, and the outer layer has a thickness of 2-5 cm, wherein the two annular liquid layers are the inner annular liquid layer 2 and the outer annular liquid layer 3.

[0025] The outer wall of the cylindrical reactor 5 is made of 304 stainless steel lined with polytetrafluoroethylene.

[0026] This embodiment utilizes the unabsorbed ultraviolet light from high-power ultraviolet lamps as a light source for treating low-TOC concentration wastewater, which can improve the utilization rate of ultraviolet light, reduce the number of photoreactors, and lower the operating cost of water treatment.

[0027] The inner liquid layer is closer to the UV lamp, so its temperature rises faster, while the outer liquid layer is relatively cooler. The water flows in opposite directions in the inner and outer liquid layers, which allows for convective heat exchange and keeps the temperature of both liquid layers relatively constant. The two annular liquid layers are separated by quartz with 95% light transmittance, which reduces the loss of UV light without disrupting the flow pattern of the two wastewater layers.

[0028] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A double-layer liquid-layer photocatalytic reactor, characterized in that, include: A cylindrical reactor with an internal cavity, the cylindrical reactor comprising a cylindrical ultraviolet lamp and two annular liquid layers; The cylindrical ultraviolet lamp is located at the center of the cylindrical reactor, with one end of the ultraviolet lamp connected to electricity, and can emit ultraviolet light in all directions. The inner layer of the two annular liquid layers wraps around the outside of the cylindrical ultraviolet lamp tube, and the outer layer of the two annular liquid layers wraps around the outside of the inner layer. The inner and outer sides of the two annular liquid layers are respectively provided with inlets and outlets. The inlet of the inner layer and the outlet of the outer layer are on the same side and adjacent to each other, while the outlet of the inner layer and the inlet of the outer layer are on the other side and adjacent to each other.

2. The double-layer liquid-layer photocatalytic reactor as described in claim 1, characterized in that: The two annular liquid layers are separated by quartz, and the thickness is 0.5-1cm.

3. The double-layer liquid-layer photocatalytic reactor as described in claim 2, characterized in that: The inner layer of the two annular liquid layers has a thickness of 1-2 cm, and the outer layer has a thickness of 2-5 cm.

4. The double-layer liquid-layer photocatalytic reactor as described in claim 3, characterized in that: The outer wall of the cylindrical reactor is made of 304 stainless steel lined with polytetrafluoroethylene.

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