Piezoelectric photocatalytic reactor based on self-driven aeration stirring

Abstract

The invention provides an innovative self-driven aeration stirring piezoelectric electro-catalytic reactor which is suitable for water treatment and disinfection. The upper part of the reactor main body is a cylinder, the lower part is a hollow cone particle hopper, and the middle part is a reaction area provided with an adjustable photocatalytic lamp source. A particle settling zone and a water outlet tank are arranged at the periphery of the reaction zone. The rotary aeration system is positioned below the reaction area, consists of paddles and perforated aeration pipes, and is connected with an aeration main pipe through a rotary movable joint; the rotary sand blasting device is composed of a sand pump and a rotary sand blasting device, the sand pump is connected with the particle hopper, and the rotary sand blasting device is located above the reaction area and connected with the sand outlet pipe through a rotary movable joint. After the piezoelectric-photocatalytic quartz sand particles are added, the device can efficiently degrade pollutants. By combining piezoelectric catalysis and photocatalysis, the sewage treatment efficiency is improved, and efficient separation of the catalyst and water is realized through the settling zone.

Description

Technical Field

[0001] The present invention relates to a water treatment reactor for water purification and disinfection, belonging to the field of water treatment and environmental protection technology. The reactor adopts a piezoelectric-photocatalytic composite material, combines the collision effect generated by aeration disturbance and stirring and the photocatalytic effect, to achieve efficient purification and disinfection of water. Background Art

[0002] As a green high-tech technology, photocatalytic technology has broad application prospects in the environmental field, has attracted widespread attention, and has been successfully applied to the degradation research of various organic pollutants.

[0003] Piezoelectric materials generate electric potential under the action of external force, and their built-in electric field can promote charge separation on a macro scale, thereby enhancing the catalytic effect. Compared with photocatalysis or electrocatalysis, piezoelectric catalysis only relies on mechanical energy and has low dependence on light and electricity.

[0004] Combining piezoelectric materials with photocatalysts is considered an effective way to achieve photoinduced carrier separation and migration. The internal electric field generated by piezoelectric materials under strain provides a driving force for the transport of photoinduced charges in and on the surface of the photocatalyst, promoting charge separation and inhibiting their recombination. This new catalytic mechanism that simultaneously utilizes light energy and mechanical energy is called "piezoelectric photocatalysis."

[0005] Patent publication number CN 114939423 A discloses a method for preparing a piezoelectric photocatalyst, which significantly improves the photocatalytic efficiency under the assistance of ultrasound.

[0006] The patent with publication number CN 112678946 A invented a self-driven rotary aeration device, which uses the power generated by aeration to drive the stirring paddle to rotate, which can promote uniform aeration and enhance the contact efficiency between water and the reaction unit.

[0007] Ultrasonic-assisted photocatalysis has high energy consumption. In order to reduce the energy consumption of piezoelectric photocatalysis, the present invention proposes to load the piezoelectric photocatalytic composite material on a carrier of 1 to 2 mm, increase the particle inertia to enhance the stress of the collision between particles, and thus enhance the piezoelectric effect. Summary of the invention

[0008] The object of the present invention is to provide a piezoelectric photocatalytic reactor based on self-driven aeration and stirring, thereby improving the efficiency of the piezoelectric photocatalytic reaction.

[0009] In order to significantly improve the efficiency of piezoelectric photocatalytic reaction, the present invention proposes the following optimization technical solutions:

[0010] First, piezoelectric photocatalytic particles with a size of 1 to 2 mm are selected as catalysts. Particles of this size can more effectively produce inertial collisions in the reactor, thereby significantly enhancing the piezoelectric effect and improving catalytic activity. Secondly, the introduction of a rotary aeration device not only promotes collisions between particles through the aeration process, further strengthening the piezoelectric effect, but also significantly increases the content of dissolved oxygen in the treated water, thereby promoting the generation of superoxide free radicals and enhancing oxidation capacity. In addition, adding a suitable light source triggers the photocatalytic oxidation effect, so that the two mechanisms of piezoelectric catalysis and photocatalysis work together to promote the catalytic reaction.

[0011] Furthermore, the present invention also introduces a sand pump (17) and a rotary sand blasting device (4-6), and the piezoelectric photocatalytic particles are evenly sucked in by the sand pump, and then the particles are evenly sprayed into the reactor by the rotary sand blasting device, thereby ensuring the uniform distribution of the piezoelectric photocatalytic particles in the reactor and further optimizing the piezoelectric photocatalytic reaction process.

[0012] Through this multi-mechanism synergistic design, the present invention not only significantly improves the efficiency of the piezoelectric photocatalytic reaction, but also ensures the stability and continuity of the reaction process, providing an efficient, innovative and practical technical solution for the field of environmental protection.

[0013] To realize the above technical solution, the present invention proposes a piezoelectric photocatalytic reactor based on self-driven aeration and stirring, including a reactor body, a rotary aeration device located inside the reactor and an external piezoelectric photocatalytic particle circulation system.

[0014] The upper part of the main body adopts a cylindrical structure, and the bottom adopts a hollow cone structure. The center of the upper part is a piezoelectric photocatalytic reaction zone (B), the periphery of the reaction zone is a sedimentation zone (C), and the hollow cone structure at the bottom is a particle hopper (A). The water inlet pipe (15) is connected to the lower part of the particle hopper. The periphery of the sedimentation zone is provided with a water outlet trough (8), and the water outlet trough is provided with a water outlet pipe (9). After the wastewater is precipitated in the sedimentation zone, it overflows into the water outlet trough and is then discharged from the reactor through the water outlet pipe.

[0015] The rotary aeration device is arranged below the reaction zone and is composed of a perforated aeration pipe (12) and a paddle (11). The paddle is located directly above the perforated aeration pipe. The rotary aeration device is connected to the aeration pipe by a rotary joint (14).

[0016] The piezoelectric photocatalytic particle circulation system consists of a circulating sand pump (17), a pipeline and a rotary sand blasting device. The inlet of the circulating sand pump is connected to the front section of the exhaust pipe (16), and the outlet end is provided with a rotary sand blasting device, which is located above the reaction zone.

[0017] Furthermore, the reaction zone is equipped with a light source (18) for stimulating photocatalysis. The light source is connected to a lifting device, and the height of the light source can be adjusted. Possible light sources include xenon lamps, LED lamps, near-infrared lamps, and ultraviolet lamps.

[0018] Furthermore, the aeration holes on the perforated aeration tube are opened horizontally, and the aeration holes are evenly arranged on the aeration branch pipes. The aeration holes on the aeration branch pipes on both sides are arranged in opposite directions, and aeration generates a counterclockwise driving force. The turbulence generated by aeration causes the piezoelectric photocatalytic particles to collide with each other, and at the same time oxygenates the water, enhancing the formation of superoxide free radicals.

[0019] Furthermore, the angle between the stirring blades on the aeration device and the horizontal plane is 15°, and the driving force generated by aeration and the driving force of the bubbles on the pulp plate cause the blades to rotate. The rotating blades have a stirring effect, which promotes mass transfer and particle collision.

[0020] Furthermore, a drain pipe is provided at the bottom of the particle hopper for discharging failed catalytic particles and for maintenance and is connected to a sand pump before the drain pipe valve.

[0021] Furthermore, the circulating sand pump can pump the photocatalytic particles deposited at the bottom of the device to the upper end of the device, and then evenly spray them into the device from the rotating sandblasting tube. The rotating sandblasting tube rotates clockwise, which is opposite to the rotation direction of the aeration device, to achieve uniform distribution of the particles in the device.

[0022] Furthermore, the rotary sandblasting device is composed of a rotary joint (6), a sandblasting tube (4), and a sandblasting port (5). The horizontal opening of the sandblasting port is in a horizontal direction, and the aperture of the sandblasting port is 8 to 12 mm. After the circulating sand pump is started, the rotary sandblasting device rotates clockwise to evenly distribute the piezoelectric photocatalytic particles.

[0023] In the technical solution of the above-mentioned self-driven aeration and stirring piezoelectric photocatalytic reactor, the piezoelectric photocatalytic material is at least one of photoresponsive catalysts such as perovskite, iron oxide, bismuth oxide, titanate, etc., or a complex of at least one of perovskite, iron oxide, bismuth oxide, titanate and titanium dioxide or zinc oxide. Common piezoelectric photocatalytic materials include lanthanum ferrite, strontium bismuth oxide, barium titanate, titanium dioxide composite bismuth titanate, etc. The piezoelectric photocatalytic material or the piezoelectric photocatalytic composite material is loaded on a 1-2 mm carrier.

[0024] In the technical solution of the self-driven aeration and stirring piezoelectric photocatalytic reactor, the carrier is 1-2 mm particles with a density slightly greater than that of water. Common carriers include hollow alumina balls, ABS plastic balls, PS plastic balls, etc.

[0025] In summary, the present invention adopts the above technical solution, and the beneficial effects of the present invention are:

[0026] In the present invention, a catalyst prepared by plating a piezoelectric photocatalyst on 1-2 mm particles is used as a piezoelectric photocatalyst. Particles of this size can more effectively produce inertial collisions in a reactor, thereby significantly enhancing the piezoelectric effect and improving the catalytic activity.

[0027] A circulating sand pump and a rotary sand blasting device are set up to achieve uniform distribution of piezoelectric photocatalytic particles in the reaction area of ​​the device. The circulating sand pump is responsible for pumping the particles at the bottom to the upper part of the device, while the rotary sand blasting device uses its unique rotating method to evenly spray the particles to the reaction area, effectively preventing local accumulation of particles and ensuring the uniformity of the reaction.

[0028] A rotary aeration device is set up, which not only achieves uniform distribution of aeration, but more importantly, it effectively promotes the collision between piezoelectric photocatalytic particles. This collision effect not only enhances the interaction between particles, but also stimulates a significant piezoelectric effect, thereby significantly improving the efficiency of the piezoelectric photocatalytic reaction. In addition, the rotary aeration device also plays a role in oxygenation during the aeration process. Through aeration, the dissolved oxygen content in the device is effectively improved, which creates favorable conditions for the generation of superoxide free radicals. As a strong oxidant, superoxide free radicals can further accelerate the catalytic reaction, thereby further enhancing the overall effect of the reaction.

[0029] The light source provides the necessary light source for the reaction zone. Under the irradiation of the light source, the piezoelectric photocatalytic particles can trigger the photocatalytic reaction, and work together with the piezoelectric effect to promote the catalytic reaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic structural diagram of a piezoelectric-photocatalytic device of the present invention.

[0031] Figure 2 It is a schematic diagram of the three-dimensional structure of a piezoelectric-photocatalytic device of the present invention.

[0032] Figure 3 It is a schematic diagram of the arrangement of the lamp tubes of the device of the present invention.

[0033] Markings in the figure: A-particle hopper, B-reaction zone, C-precipitation zone; 1-device body, 2-circulation pipe, 3-lifting device, 4-rotating sandblasting tube, 5-sandblasting port, 6-rotating joint (sandblasting tube), 7-baffle, 8-water outlet trough, 9-water outlet pipe, 10-piezoelectric photocatalytic particles, 11-paddle, 12-aeration pipe, 13-aeration hole, 14-rotating joint (aeration pipe), 15-water inlet pipe, 16-emptying pipe, 17-circulating sand pump, 18-lamp tube, 19-lamp holder. DETAILED DESCRIPTION

[0034] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings and technical solutions.

[0035] Piezoelectric-photocatalytic particles are added to the reactor, and oxygen aeration is performed while water is introduced. The rotary aeration device performs aeration and stirring functions, and the particles are flushed by the water. The photocatalytic lamp is turned on to perform piezoelectric-photocatalytic degradation of the water.

[0036] After the water body is degraded, it passes through the water flow channel and enters the sedimentation area for separation of particles and water flow.

[0037] The piezoelectric-photocatalytic particles deposited at the bottom of the device are pumped to the upper end of the device by a circulating sand pump, and then evenly sprayed into the device by a rotating sand blasting device, so that the piezoelectric photocatalytic particles are evenly distributed in the reaction area, thereby enhancing the efficiency of the piezoelectric photocatalytic reaction.

[0038] The piezoelectric photocatalytic particles in the circulation pipe rub and collide with the pipe, which can generate mechanical stress, stimulate its piezoelectric effect, and clean the surface of the piezoelectric photocatalytic particles, so that the piezoelectric photocatalytic particles can receive more light sources, further enhancing the treatment effect.

[0039] The purified or disinfected water will flow through the sedimentation area to the drain tank and then be discharged through the outlet pipe.

Claims

1. A piezoelectric photocatalytic reactor based on self-driven aeration and stirring, characterized in that: The invention comprises a reactor body, a rotary aeration device located inside the reactor and a photocatalytic particle circulation system. The upper part of the reactor shell is cylindrical, the lower part is a conical particle hopper (A), the lower end of the particle hopper is provided with an emptying pipe, the water inlet pipe is located below the particle hopper, the middle part of the cylinder is a reaction zone (B), the reaction zone is provided with a photocatalytic lamp source, the periphery of the reaction zone is provided with a precipitation zone (C), the water outlet trough is located at the periphery of the upper part of the reactor, and the water outlet trough is connected to the water outlet pipe; the rotary aeration device is located below the reaction zone, and is composed of a blade (11) and a perforated aeration pipe (12), the blade is located just above the perforated aeration pipe, and the rotary aeration device is connected to the aeration pipe by a rotary joint (14); the particle circulation system is composed of a sand pump (17) and a rotary sandblasting device, the sand pump is connected to the upper end of the emptying pipe, the sand pump outlet is connected to the rotary sandblasting device, the rotary sandblasting device is located above the reaction zone, and the rotary sandblasting device is connected to the pipeline by a rotary joint (6).

2. A piezoelectric-photocatalytic reaction device as claimed in claim 1, characterized in that: The photocatalytic frame (20) is connected to the lifting device (3) and can adjust the height of the light source.

3. A piezoelectric-photocatalytic reaction device as claimed in claim 1, characterized in that: The lamp tube (19) has the characteristics of corrosion resistance, aging resistance, high strength, etc.

4. A piezoelectric-photocatalytic reaction device as claimed in claim 1, characterized in that: The aeration holes (13) on the perforated aeration pipe (12) of the rotary aeration device are arranged horizontally, and the angle between the blades (11) and the horizontal is 15° to 20°.

5. The piezoelectric-photocatalytic reaction device according to claim 1, characterized in that: The water inlet pipe of the sand pump (17) is arranged at the bottom of the device, the water outlet pipe is arranged at the top of the device, and a rotary sandblasting device is arranged at the end of the water outlet pipe, which is composed of a rotary joint (6), a sandblasting pipe (4), and a sandblasting port (5). The horizontal opening of the sandblasting port is in the horizontal direction, and the aperture of the sandblasting port is 8 to 12 mm.

6. A water treatment method, characterized in that: The method uses the piezoelectric photocatalytic sewage treatment device described in any one of claims 1 to 6, and comprises the following steps: adding the piezoelectric photocatalytic material into the reactor through the grid holes on the device, allowing wastewater to enter the reactor through the water inlet, and then turning on the light source (18), the circulation pump (17) and the rotary aeration device to treat the wastewater, wherein the treated wastewater is precipitated in the sedimentation zone (C), overflows into the water outlet tank (8), and then is discharged from the reactor through the water outlet pipe (9); the piezoelectric photocatalytic material is a composite material of piezoelectric material and photocatalytic material, and the gas introduced by aeration is air; the reaction time of the wastewater in the reactor is controlled to be 1.0 to 3.0 hours; after the piezoelectric photocatalytic particles sink to the particle hopper, they are evenly distributed above the reaction zone through the particle circulation system, and the rotary aeration device below the reaction zone has a stirring and driving effect on the piezoelectric photocatalytic particles, promoting their collision to generate piezoelectric effect, and generating free radicals under the piezoelectric catalysis and photocatalysis in the reaction zone to degrade pollutants in the wastewater.

7. The wastewater treatment method according to claim 6, characterized in that: The piezoelectric photocatalytic material is plated on the surface of a carrier (such as PS plastic balls, hollow alumina balls, etc.), the carrier density is greater than the wastewater density, and the material particle size is 1 mm to 2 mm.

8. The wastewater treatment method according to claim 6, characterized in that: The piezoelectric photocatalytic composite material (support material) is added in an amount of 100 to 300 g per liter of wastewater.

9. The wastewater treatment method according to claim 6, characterized in that: During aeration, the aeration intensity can meet the rotation speed of the rotary aeration device of 100 to 280 r / min.

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