Photocatalytic Oxidation Reaction Device

Abstract

The present invention provides a photocatalytic oxidation reaction device, which includes a photocatalytic oxidation reactor for purifying wastewater. An ultraviolet sterilization lamp group and a second aeration device for providing ozone are arranged on the photocatalytic oxidation reactor. The second aeration device is arranged at the bottom of the photocatalytic oxidation reactor and aerates from bottom to top. The ultraviolet sterilization lamp group is arranged in the photocatalytic oxidation reactor above the second aeration device. The ultraviolet sterilization lamp group includes a plurality of ultraviolet sterilization lamps, and the ultraviolet sterilization lamps are evenly distributed in the photocatalytic oxidation reactor. In this solution, ozone is used as an oxidant and the light of the ultraviolet sterilization lamp is used as a catalyst. Through the photocatalytic oxidation technology, the purification treatment of wastewater is realized. The pollutants in the wastewater can be finally mineralized into carbon dioxide, water and inorganic salts without selectivity, and no sludge will be generated and no secondary pollution will be caused.

Description

Technical Field

[0001] The present invention belongs to the field of wastewater treatment, and particularly relates to a photocatalytic oxidation reaction device. Background Art

[0002] With the prosperous development of the industrial economy, the water consumption has increased sharply, and the corresponding amount of wastewater has also increased rapidly. Water pollutants mainly come from industrial, agricultural, medical, and domestic wastewater. A large number of toxic and harmful substances have caused serious harm to the environment and ecological safety. Water environmental pollution has become increasingly serious, and the carrying capacity of water bodies has been severely challenged. Traditional wastewater treatment methods such as adsorption, extraction, coagulation precipitation, chemical precipitation, and membrane separation can only play the role of phase separation and cannot completely remove pollutants. Advanced oxidation technology is an effective means to strengthen wastewater treatment and has attracted much attention in the field of water treatment in recent years. Since the chemical properties of refractory pollutants are relatively stable, common chemical oxidants cannot completely mineralize them, so free radicals with higher oxidation ability must be used to completely remove pollutants.

[0003] Existing advanced oxidation technologies for wastewater treatment include Fenton oxidation technology, ozone oxidation technology, etc. However, due to the utilization rate of hydrogen peroxide in Fenton oxidation technology being less than 50%, and the incomplete mineralization of organic matter during the reaction will form more toxic intermediate products, such as Fe(OH)3. And the sludge formed by Fe(OH)3 during the reaction will cause serious secondary pollution and have limited effect on improving the biodegradability of wastewater. Ozone oxidation has low ozone utilization efficiency and high preparation cost, is suitable for the treatment of the tail end of low-concentration wastewater, and has low treatment efficiency for high-concentration refractory wastewater. Summary of the Invention

[0004] In view of the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide a photocatalytic oxidation reaction device to quickly decompose organic matter and odor substances in water under the condition of not generating a large amount of sludge.

[0005] To achieve the above purpose and other related purposes, the present invention provides a photocatalytic oxidation reaction device, including a photocatalytic oxidation reactor for purifying wastewater. An ultraviolet sterilization lamp group and a second aeration device for providing ozone are arranged on the photocatalytic oxidation reactor. The second aeration device is arranged at the bottom of the photocatalytic oxidation reactor and aerates from bottom to top. The ultraviolet sterilization lamp group is arranged in the photocatalytic oxidation reactor above the second aeration device. The ultraviolet sterilization lamp group includes several ultraviolet sterilization lamps, and the ultraviolet sterilization lamps are evenly distributed in the photocatalytic oxidation reactor.

[0006] Furthermore, an ozone tail gas destroyer is also connected and arranged on the photocatalytic oxidation reactor, and the ozone tail gas destroyer is connected to the top end of the photocatalytic oxidation reactor.

[0007] Further, the second aeration device includes a second aeration disc, which is arranged in the photocatalytic oxidation reactor under the ultraviolet sterilization lamp group. An ozone generator is communicated with the second aeration disc, and the ozone generator is arranged outside the photocatalytic oxidation reactor.

[0008] Further, ozone oxidation catalysts and a water collector are arranged around the second aeration disc, and the water collector is arranged under the ozone oxidation catalysts.

[0009] Further, a pressure stabilizing pipe is communicated with the water collector. One end of the pressure stabilizing pipe is communicated with the water collector in the photocatalytic oxidation reactor, and the other end of the pressure stabilizing pipe bends downward to discharge water after reaching the required water level height in the photocatalytic oxidation reactor.

[0010] Further, a water distribution weir trough is also arranged in the photocatalytic oxidation reactor. The water distribution weir trough is located at the water inlet position of the photocatalytic oxidation reactor, and the ultraviolet sterilization lamp group is arranged vertically and penetrates through the water distribution weir trough.

[0011] Further, the ultraviolet sterilization lamp is in a straight strip shape. An upper stabilizing plate is arranged at the top end of the ultraviolet sterilization lamp, and a lower stabilizing plate is arranged at the bottom end of the ultraviolet sterilization lamp. Both the upper stabilizing plate and the lower stabilizing plate are fixed to the inner wall of the photocatalytic oxidation reactor. The ultraviolet sterilization lamp is fixed between the upper stabilizing plate and the lower stabilizing plate, and a plurality of water distribution holes are uniformly formed in the lower stabilizing plate.

[0012] Further, a fixing plate is also arranged between the top end and the bottom end of the ultraviolet sterilization lamp. The ultraviolet sterilization lamp penetrates through the fixing plate. A flow disturbing plate protrudes from the fixing plate, and the flow disturbing plate is obliquely fixed to the fixing plate. A plurality of water distribution holes are uniformly distributed on the fixing plate.

[0013] Further, it also includes a water inlet device and a pretreatment reactor. The water inlet device includes a lift pump, a medicine tank, a medicine adding pump and a mixer. The medicine adding pump is communicated with the medicine tank, and both the medicine adding pump and the lift pump are communicated with the water inlet of the mixer. A medicine liquid for adjusting the pH value of the wastewater is placed in the medicine tank. A water inlet pipe is communicated with the outlet of the mixer, and the water inlet pipe is communicated with the pretreatment reactor.

[0014] Further, a pre-reaction tank, a collection tank and a first aeration device are arranged in the pretreatment reactor. The water inlet pipe is communicated with the pre-reaction tank. The collection tank is arranged on one side of the top end of the pre-reaction tank and is communicated with the pre-reaction tank. A flowmeter and a pH detector are arranged on the water inlet pipe, and the pH detector is located in the pre-reaction tank. The water outlet of the pre-reaction tank is lower than the communication position between the pre-reaction tank and the collection tank; the first aeration device is arranged in the pre-reaction tank.

[0015] As described above, the photocatalytic oxidation reaction device of the present invention has the following beneficial effects:

[0016] In this solution, ozone is used as the oxidant, and the light of the ultraviolet sterilization lamp is used as the catalyst. Through the photochemical synergistic oxidation technology, the purification treatment of wastewater is realized. The pollutants in the wastewater can be finally mineralized into carbon dioxide, water and inorganic salts without selectivity, and no sludge or secondary pollution will be generated. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic structural diagram of the photocatalytic oxidation reaction device in the embodiment of the present invention.

[0018] Figure 2 It is a schematic internal structure diagram of the photocatalytic oxidation reactor in the embodiment of the present invention.

[0019] Figure 3 It is a schematic structural diagram of the fixing plate in the embodiment of the present invention.

[0020] Figure 4 It is a schematic distribution diagram of the second aeration disk and the water collector on the bottom plate in the embodiment of the present invention.

[0021] Figure 5 It is a schematic structural diagram of the spoiler in the embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0022] The reference numerals in the attached drawings of the specification include: lift pump 1, mixer 2, chemical dosing pump 3, medicine tank 4, water inlet pipe 5, pretreatment reactor 6, collection tank 7, pre-reaction tank 8, PH detector 9, flowmeter 10, first aeration disk 11, air pump 12, connecting pipe 13, photocatalytic oxidation reactor 14, ozone tail gas destroyer 15, electric wire 16, ultraviolet sterilization lamp 17, water distribution weir tank 18, fixing plate 19, upper stabilizing plate 20, lower stabilizing plate 21, ozone oxidation catalyst 22, second aeration disk 23, ozone generator 24, pressure stabilizing pipe 26, water collector 28, bottom plate 29, air pipe 30, spoiler 31, water distribution hole 32.

[0023] The following specific embodiments illustrate the implementation manners of the present invention. Those skilled in the art can easily understand the other advantages and effects of the present invention from the content disclosed in this specification.

[0024] Embodiment

[0025] As Figures 1 to 5 shown, this embodiment provides a photocatalytic oxidation reaction device, including: a water inlet device, a pretreatment reactor 6 and a photocatalytic oxidation reactor 14.

[0026] The water inlet device includes a lift pump 1, a medicine tank 4, a medicine adding pump 3 and a mixer 2. The lift pump 1 is used to pump out the accumulated wastewater. The medicine adding pump 3 is connected to the medicine tank 4 and is used to pump out the liquid medicine in the medicine tank 4. The liquid medicine in the medicine tank 4 is an acidic or alkaline solution and is used to adjust the pH value of the wastewater. Both the lift pump 1 and the medicine adding pump 3 are connected to the water inlet of the mixer 2. The mixer 2 mixes the wastewater pumped out by the lift pump 1 and the liquid medicine pumped out by the medicine adding pump 3, and then exits from the water outlet of the mixer 2. A water inlet pipe 5 is connected to the water outlet of the mixer 2, and the water inlet pipe 5 is connected to a pretreatment reactor 6.

[0027] A valve is provided on the water inlet pipe 5 to control the entry of wastewater from the water inlet pipe 5 into the pretreatment reactor 6. A flow meter 10 and a pH detector 9 are also provided on the water inlet pipe 5. The flow meter 10 is used to count the flow rate of the wastewater entering the pretreatment reactor 6, and the pH detector 9 is used to detect the pH value of the wastewater in the pretreatment reactor 6.

[0028] The pretreatment reactor 6 includes a pre-reaction tank 8 and a collection tank 7. The collection tank 7 is located on one side at the top of the pre-reaction tank 8 and is connected to the pre-reaction tank 8. In this solution, the height of the water inlet of the water inlet pipe 5 on the pretreatment reactor 6 is higher than the height of the connection position between the collection tank 7 and the pre-reaction tank 8.

[0029] A first aeration device is provided at the bottom of the pre-reaction tank 8. The first aeration device includes an air pump 12 and a first aeration disc 11. The first aeration disc 11 is located at the bottom of the pre-reaction tank 8 and is connected to the air pump 12. The air pump 12 is arranged outside the pretreatment reactor 6. The first aeration device is provided to increase the dissolved oxygen content of the wastewater in the pretreatment reactor 6. The collection tank 7 is provided to facilitate the overflow of bubbles and scum from the pre-reaction tank 8 into the collection tank 7 for cleaning the bubbles and scum in the pre-reaction tank 8. A pipe for communicating with the outside is provided at the bottom of the collection tank 7, and a valve is provided on the pipe to facilitate the cleaning of the scum and bubbles in the collection tank 7. And the pretreatment reactor 6 in this solution is used for the pre-oxidation of wastewater, aiming to enable the wastewater mixed with medicine to be better mixed in the pretreatment reactor 6, adjust and control the pH value of the wastewater, and at the same time introduce air into the pre-reaction tank 8 through the first aeration device to increase the dissolved oxygen content of the wastewater in the pre-reaction tank 8, preparing for the subsequent wastewater purification.

[0030] The photocatalytic oxidation reactor 14 and the pretreatment reactor 6 are connected through a connecting pipe 13, so that the wastewater in the pretreatment reactor 6 can enter the photocatalytic oxidation reactor 14. A water distribution weir trough 18 is arranged in the photocatalytic oxidation reactor 14, and the connecting pipe 13 is communicated with the side wall of the water distribution weir trough 18. The water distribution weir trough 18 is disc-shaped. A number of holes are evenly formed in the water distribution weir trough 18, so that the wastewater can flow out of the water distribution weir trough 18. An ultraviolet sterilization lamp group is vertically arranged through the water distribution weir trough 18. The ultraviolet sterilization lamp group is composed of a plurality of ultraviolet sterilization lamps 17. The lamp tubes outside each ultraviolet sterilization lamp 17 adopt quartz sleeves. The ultraviolet sterilization lamps 17 are arranged vertically in the photocatalytic oxidation reactor 14. An upper stabilizing plate 20 is arranged at the top of the ultraviolet sterilization lamp 17. The upper stabilizing plate 20 is fixedly connected with the inside of the pretreatment reactor 6, and the lower stabilizing plate 20 is located above the water distribution weir trough 18 to avoid being flooded by the wastewater. An installation opening for the ultraviolet sterilization lamp 17 is formed in the upper stabilizing plate 20, and the ultraviolet sterilization lamp 17 is installed in the corresponding installation opening. The wire 16 of the ultraviolet sterilization lamp 17 goes out from the installation opening to facilitate the power supply to the ultraviolet sterilization lamp 17. The irradiation wavelength of the ultraviolet sterilization lamp 17 in this embodiment is 172nm - 254nm.

[0031] A lower stabilizing plate 21 for installing the ultraviolet sterilization lamp 17 is arranged at the bottom end of the ultraviolet sterilization lamp group. The lower stabilizing plate 21 is fixedly connected with the photocatalytic oxidation reactor 14, and an installation opening for the ultraviolet sterilization lamp 17 is arranged on the lower stabilizing plate 21. The ultraviolet sterilization lamp 17 is inserted into the installation opening. A fixing plate 19 is further arranged between the top end and the bottom end of the ultraviolet sterilization lamp 17. The fixing plate 19 is fixedly connected with the inner wall of the photocatalytic oxidation reactor 14. A flow disturbing plate 31 is convexly fixed on the fixing plate 19. The flow disturbing plate 31 is similar in shape to a fan blade. The distribution of the ultraviolet sterilization lamps 17 on the fixing plate 19 is as Figure 3 shown. One ultraviolet sterilization lamp 17 is arranged at the circumferential position of the fixing plate 19, and the remaining ultraviolet sterilization lamps 17 are arranged in circles with the middle ultraviolet sterilization lamp 17 as the center. The distance between two adjacent ultraviolet sterilization lamps 17 in each circle is 114.8mm, and the distance between two adjacent circles of ultraviolet sterilization lamps 17 is 110mm. The ultraviolet sterilization lamp 17 passes through the fixing plate 19, and a number of water distribution holes 32 are formed in both the fixing plate 19 and the lower stabilizing plate 21. The water distribution holes 32 are mainly formed for the flow of wastewater and the passage of gas. The flow disturbing plate 31 is arranged to disturb the water flow and form a turbulent flow, so as to increase the contact area and contact time between the wastewater and the ultraviolet sterilization lamp 17 and increase the oxidation effect. The distance between the ultraviolet sterilization lamps 17 in this solution is reasonable, and the annular layout is adopted, so that the ultraviolet light intensity distribution is uniform, and the pollutants can be decomposed efficiently and quickly. The ultraviolet sterilization lamps 17 are arranged in the vertical direction to avoid the accumulation of sediment outside the ultraviolet sterilization lamps 17.

[0032] A second aeration device is installed on the bottom plate 29 of the photocatalytic oxidation reactor 14. The second aeration device is arranged in the photocatalytic oxidation reactor 14 below the lower stabilizing plate 21. The second aeration device includes a second aeration disc 23. An ozone generator 24 (as shown in Figure 4 ) is connected to the second aeration disc 23 through a gas pipe 3. The ozone generated by the ozone generator 24 enters the photocatalytic oxidation reactor 14 through the second aeration disc 23. In this embodiment, a total of seven second aeration discs 23 are provided. One second aeration disc 23 is arranged at the center position of the bottom plate 29, and the remaining second aeration discs 23 are evenly arranged around the central second aeration disc 23. A water collector 28 for discharging water from the photocatalytic oxidation reactor 14 is also arranged on the bottom plate 29. Ozone oxidation catalysts 22 are arranged around the water collector 28 and the second aeration disc 23. In this embodiment, the second aeration disc 23 is arranged at the bottom of the photocatalytic oxidation reactor 14, while the water outlet position of the connecting pipe 13 is close to the top of the photocatalytic oxidation reactor 14, so that ozone and wastewater are mixed in a countercurrent manner, allowing ozone and water to have a sufficient mixing area and mixing time, realizing the efficient utilization of ozone, greatly improving the oxidation efficiency of the reactor. The setting of the ozone oxidation catalyst 22 further increases the utilization rate of ozone. Since the ozone oxidation catalyst 22 in this solution is an existing product, it will not be described here.

[0033] A pressure stabilizing pipe 26 is connected to the water collector 28. The left end of the pressure stabilizing pipe 26 is connected to the water collector 28, and the right end of the pressure stabilizing pipe 26 bends upward to the water level height below the water distribution weir trough 18 (the water level in the photocatalytic oxidation reactor 14 is lower than the water distribution weir trough 18) and then bends downward. The setting of the pressure stabilizing pipe 26 forms a U-shaped tubular structure with the photocatalytic oxidation reactor 14 to increase the stability of the water pressure in the photocatalytic oxidation reactor 14. At the same time, it increases the residence time of water in the photocatalytic oxidation reactor 14 to increase the treatment time of wastewater in the photocatalytic oxidation reactor 14, giving wastewater and ozone sufficient fusion time, making the oxidation reaction more thorough and the wastewater treatment cleaner.

[0034] An ozone tail gas destroyer 15 is also connected to the top of the photocatalytic oxidation reactor 14. The ozone tail gas destroyer 15 is provided to prevent ozone odor from overflowing into the air.

[0035] During specific implementation, the lift pump 1 pumps the wastewater into the mixer 2, and the chemical dosing pump 3 pumps the liquid medicine in the medicine tank 4 into the mixer 2. After the wastewater and the liquid medicine are mixed in the mixer 2, they enter the pretreatment reactor 6 through the water inlet pipe 5. While the liquid medicine plays a role in adjusting the pH value of the wastewater in the pretreatment reactor 6, the first aeration device introduces air into the pretreatment reactor 6 to increase the oxygen content of the wastewater in the pretreatment reactor 6, adjust the pH value of the wastewater, and prepare for the subsequent wastewater treatment in the photocatalytic oxidation reactor 14. When the water level of the wastewater in the pretreatment reactor 6 reaches the top of the collection tank 7, the bubbles and scum in the wastewater overflow into the collection tank 7, and then the valve at the bottom end of the collection tank 7 is opened to discharge the scum and bubbles in the collection tank 7.

[0036] The wastewater pretreated by the pretreatment reactor 6 enters the photocatalytic oxidation reactor 14 through the connecting pipe 13, and then is evenly distributed by the water distribution weir tank 18, so that the wastewater is evenly distributed in the photocatalytic oxidation reactor 14 for oxidation treatment. In the photocatalytic oxidation reactor 14, ozone enters the photocatalytic oxidation reactor 14 through the second aeration device. Ozone is used as an oxidant, and the ultraviolet light of the ultraviolet sterilization lamp 17 is used as a catalyst. In order to increase the utilization rate of ozone, an ozone oxidation catalyst 22 is added. The purification treatment of wastewater is realized through photocatalytic oxidation technology, and the pollutants in the wastewater can be finally mineralized into carbon dioxide, water and inorganic salts without selectivity, and no secondary pollution will be generated. The residual ozone enters the ozone tail gas destructor 15 from the top of the photocatalytic oxidation reactor 14 for treatment, and the water purified by the photocatalytic oxidation reactor 14 enters the pressure stabilizing pipe 26 from the water collector 28 and exits from the pressure stabilizing pipe 26 for use.

[0037] In addition, the second aeration disc 23 in this solution uses a titanium plate for gas distribution, and the pore diameter of its gas distribution holes is 5-20um. Ozone can be fully cut into small bubbles, improving the utilization rate of ozone.

[0038] The above embodiments are only illustrative of the principles and effects of the present invention, and are not used to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A photocatalytic oxidation reaction device, characterized in that, It includes a photocatalytic oxidation reactor for purifying wastewater. An ultraviolet sterilization lamp group and a second aeration device for providing ozone are provided on the photocatalytic oxidation reactor. The second aeration device is arranged at the bottom of the photocatalytic oxidation reactor and aerates from bottom to top. The ultraviolet sterilization lamp group is arranged in the photocatalytic oxidation reactor above the second aeration device. The ultraviolet sterilization lamp group includes several ultraviolet sterilization lamps, and the ultraviolet sterilization lamps are evenly distributed in the photocatalytic oxidation reactor. It also includes a water inlet device and a pretreatment reactor. The water inlet device includes a lift pump, a medicine tank, a medicine adding pump and a mixer. The medicine adding pump is communicated with the medicine tank, and both the medicine adding pump and the lift pump are communicated with the water inlet of the mixer. A liquid medicine for adjusting the pH value of the wastewater is placed in the medicine tank. A water inlet pipe is communicated with the outlet of the mixer, and the water inlet pipe is communicated with the pretreatment reactor. A pre-reaction tank, a collection tank and a first aeration device are arranged in the pretreatment reactor. The water inlet pipe is communicated with the pre-reaction tank. The collection tank is arranged on one side of the top of the pre-reaction tank and is communicated with the pre-reaction tank. A flow meter and a pH detector are arranged on the water inlet pipe, and the pH detector is located in the pre-reaction tank. The water outlet of the pre-reaction tank is lower than the communicating position between the pre-reaction tank and the collection tank. The first aeration device is arranged in the pre-reaction tank. A fixing plate is also arranged between the top and the bottom of the ultraviolet sterilization lamp. The ultraviolet sterilization lamp penetrates through the fixing plate. A spoiler is convexly arranged on the fixing plate. The spoiler is obliquely fixed on the fixing plate. A number of water distribution holes are evenly distributed on the fixing plate.

2. The photocatalytic oxidation reaction device according to claim 1, characterized in that, An ozone tail gas destroyer is also communicated and arranged on the photocatalytic oxidation reactor. The ozone tail gas destroyer is communicated with the top of the photocatalytic oxidation reactor.

3. The photocatalytic oxidation reaction device according to claim 1, characterized in that, The second aeration device includes a second aeration disc. The second aeration disc is arranged in the photocatalytic oxidation reactor under the ultraviolet sterilization lamp group. An ozone generator is communicated with the second aeration disc. The ozone generator is arranged outside the photocatalytic oxidation reactor.

4. The photocatalytic oxidation reaction device according to claim 3, characterized in that, Ozone oxidation catalysts and a water collector are arranged around the second aeration disc. The water collector is arranged under the ozone oxidation catalysts.

5. The photocatalytic oxidation reaction device according to claim 4, characterized in that, A pressure stabilizing pipe is communicated with the water collector. One end of the pressure stabilizing pipe is communicated with the water collector in the photocatalytic oxidation reactor. The other end of the pressure stabilizing pipe bends downward to discharge water after reaching the required water level height in the photocatalytic oxidation reactor.

6. The photocatalytic oxidation reaction device according to claim 1, characterized in that, A water distribution weir trough is also arranged in the photocatalytic oxidation reactor. The water distribution weir trough is located at the water inlet position of the photocatalytic oxidation reactor. The ultraviolet sterilization lamp group is arranged vertically and penetrates through the water distribution weir trough.

7. The photocatalytic oxidation reaction device according to claim 6, characterized in that, The ultraviolet sterilization lamp is in a straight strip shape. An upper stabilizing plate is arranged at the top of the ultraviolet sterilization lamp. A lower stabilizing plate is arranged at the bottom of the ultraviolet sterilization lamp. Both the upper stabilizing plate and the lower stabilizing plate are fixed to the inner wall of the photocatalytic oxidation reactor. The ultraviolet sterilization lamp is fixed between the upper stabilizing plate and the lower stabilizing plate. A number of water distribution holes are evenly opened on the lower stabilizing plate.

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