An apparatus for synergistic pretreatment inactivation of algal cells by ultrasound and chlorine dioxide

Abstract

This invention discloses a device for the synergistic pretreatment of algal cells by ultrasound and chlorination to inactivate them. The device includes a mixing reaction tank with an inlet pipe at one end, a chlorination oxidant dosing point connected to the inlet pipe, and an outlet pipe at the other end. It also includes an ultrasonic radiation device comprising a sound signal generator and a probe transducer electrically connected. The probe transducers are evenly arranged at the bottom of the reaction tank along the water flow direction and facing upwards; or the probe transducers are arranged on both sides of the mixing reaction tank walls, positioned below the liquid surface and facing the center of the water flow cross-section. This invention utilizes the synergistic effect of ultrasound and chlorination to effectively reduce chlorine dosage, increase algae removal rate, reduce water treatment costs, and improve the efficiency of subsequent processes, resulting in significant energy saving and emission reduction effects.

Description

Technical Field

[0001] This utility model relates to the field of water treatment, and in particular to a device for the synergistic pretreatment of algal cells by ultrasound and chlorination to inactivate them. Background Technology

[0002] With the worsening of global eutrophication, abnormal algal blooms have become a common phenomenon in rivers, lakes, and other aquatic bodies. These excessive algal growths cause serious harm to humans, animals, and the ecological environment. Algae-laden water can clog filters and produce disinfection byproducts during water treatment, affecting water supply safety and increasing the operating costs of water treatment plants. Therefore, effective measures must be taken to mitigate the harm caused by algal blooms.

[0003] Traditional pretreatment methods for algae-containing water mainly include chemical pre-oxidation, powdered activated carbon adsorption, or biological pretreatment. Among chemical pre-oxidation methods, pre-chlorination is widely used due to its high cost-effectiveness. However, when the dosage of various pre-oxidation agents is large, they may counteract each other with coagulants and adsorbents, and easily lead to the release of large amounts of intracellular substances, thus reducing the effectiveness of odor removal, algae control, and coagulation aid. Therefore, using low-dose pre-chlorination in combination with other technologies while ensuring pre-oxidation effectiveness will become a new development direction for the pretreatment of algae-containing water. Summary of the Invention

[0004] To solve the above-mentioned technical problems, this utility model provides a device for the synergistic pretreatment of algal cells by ultrasound and chlorination oxidation, which is simple in structure, low in energy consumption, and has good safety.

[0005] The technical solution of this utility model to solve the above-mentioned technical problems is: a device for the synergistic pretreatment of algal cell inactivation by ultrasound and chlorination, comprising a mixing reaction tank, an inlet pipe at one end of the mixing reaction tank, an inlet valve on the inlet pipe, a chlorination oxidant dosing point on the inlet pipe, the chlorination oxidant dosing point being connected to a chlorinator, an outlet pipe at the other end of the mixing reaction tank, an outlet valve on the outlet pipe, and an ultrasonic radiation device, the ultrasonic treatment device comprising a sound signal generator and a probe transducer, the sound signal generator and the probe transducer being electrically connected, the probe transducers being uniformly arranged at the bottom of the reaction tank along the water flow direction and facing upwards; or the probe transducers being arranged on both sides of the mixing reaction tank, the arrangement position being below the liquid surface and facing the center of the water flow cross section.

[0006] In the aforementioned device for the synergistic pretreatment of algal cells by ultrasound and chlorination to inactivate them, several guide walls are alternately arranged on both sides of the mixing reaction tank, which divide the mixing reaction tank into S-shaped water flow channels.

[0007] The aforementioned device for the synergistic pretreatment of algal cells by ultrasound and chlorination to inactivate them includes a mechanical stirring device installed at the starting position of the water flow channel.

[0008] The aforementioned apparatus for the synergistic pretreatment of algal cells by ultrasound and chlorination to inactivate them includes a mixing reaction tank equipped with multiple drainage pipes.

[0009] The aforementioned device for the synergistic pretreatment of algal cells by ultrasound and chlorination to inactivate them includes multiple flow promoters distributed along the water flow direction within the mixing reaction tank.

[0010] The aforementioned device for the synergistic pretreatment of algal cells by ultrasound and chlorination to inactivate them also includes a bypass pipe, one end of which is connected to the inlet pipe and the other end of which is connected to the outlet pipe, and a valve is provided on the bypass pipe.

[0011] In the aforementioned device for the synergistic pretreatment of algal cells by ultrasound and chlorination to inactivate them, the residence time of the raw water entering the mixing reaction tank from the inlet pipe is 3 to 5 minutes.

[0012] The aforementioned device for the synergistic pretreatment of algal cells by ultrasound and chlorination to inactivate them has an ultrasound radiation frequency of 40 kHz to 120 kHz and an ultrasound radiation treatment time of not less than 3 min.

[0013] The beneficial effects of this utility model are as follows:

[0014] 1. This utility model utilizes the synergistic effect of ultrasound and chlorine oxidation to effectively reduce the amount of chlorine added, improve the algae removal rate, reduce water treatment costs, and improve the treatment efficiency of subsequent processes, resulting in significant energy saving and emission reduction effects.

[0015] 2. This invention features multiple flow promoters distributed along the water flow direction within the mixing reaction tank, which enhances the mixing effect of chlorine and algal cells and adjusts and controls the direction and speed of the water flow.

[0016] 3. This utility model has several guide walls arranged alternately on both sides of the mixing reaction tank. The guide walls divide the mixing reaction tank into S-shaped water flow channels. The guide walls can enhance water flow, balance water flow, and prevent short-circuiting and stagnant water areas. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of this utility model.

[0018] Figure 2 This is a schematic diagram of the ultrasonic processing device. Detailed Implementation

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0020] like Figure 1 , Figure 2 As shown, an apparatus for the synergistic pretreatment of algal cell inactivation by ultrasound and chlorination includes a mixing reaction tank 1, a bypass pipe 10, and an ultrasonic radiation device. One end of the mixing reaction tank 1 is provided with an inlet pipe 2, which is equipped with an inlet valve 11 and a chlorination oxidant dosing point 3 connected to a chlorinator 14. The other end of the mixing reaction tank 1 is provided with an outlet pipe 9, which is equipped with an outlet valve 12. The ultrasonic treatment device includes a sound signal generator 15 and a probe transducer 8, which are electrically connected. The probe transducer 8 is evenly arranged at the bottom of the reaction tank along the water flow direction and faces upward; or the probe transducer 8 is arranged on both sides of the mixing reaction tank 1, positioned below the liquid surface and facing the center of the water flow cross-section.

[0021] Several guide walls 4 are arranged alternately on both sides of the mixing reaction tank 1. The guide walls 4 divide the mixing reaction tank 1 into S-shaped water flow channels. The guide walls 4 can enhance water flow, balance water flow, and prevent short-circuiting and stagnant water areas.

[0022] A mechanical stirring device 5 is installed at the beginning of the water flow channel, which ensures that the chlorinating agent and the raw water are fully and evenly mixed.

[0023] The mixing reaction tank 1 is equipped with multiple drain pipes 7. When the equipment is damaged and needs repair, the water in the mixing reaction tank 1 can be drained through the drain pipes 7.

[0024] Multiple flow promoters 6 are distributed along the water flow direction in the mixing reaction tank 1, which can enhance the mixing effect of chlorine and algal cells, and adjust and control the direction and speed of water flow.

[0025] The chlorination oxidizing agent is an aqueous solution of chlorinating agents such as sodium chlorate, chlorine dioxide, and calcium hypochlorite.

[0026] One end of the bypass pipe 10 is connected to the inlet pipe 2, and the other end of the bypass pipe 10 is connected to the outlet pipe 9. A valve 13 is provided on the bypass pipe 10. When the inlet water quality is good and no additional pretreatment is required, the inlet water can be directly discharged through the bypass pipe 10.

[0027] The size of the mixing reaction tank 1 is designed according to the water volume. The residence time of the raw water entering the mixing reaction tank 1 from the inlet pipe 2 is 3 to 5 minutes.

[0028] The ultrasonic radiation frequency of the ultrasonic treatment device is 40 kHz to 120 kHz, and the ultrasonic radiation treatment time is not less than 3 minutes.

[0029] The chlorine dosage is determined based on the available chlorine, which is 0.4–1.0 mg / L.

[0030] The working mechanism of this invention is as follows: The raw water containing algae is subjected to dynamic ultrasonic pretreatment while a chlorinating agent is added to the tank. After ultrasonic and chlorination pretreatment, the surface structure of algal cells is damaged under the action of the chlorinating agent, including zeta potential and organic group structures. Under the action of ultrasound, the internal structure and physiological metabolism of algal cells are damaged, including air sacs, cytoplasm, photosynthetic system, and genetic material transcription. Under the synergistic effect of ultrasound and chlorination, algal cells enter a sublethal inactivation state, releasing less intracellular organic matter compared to chlorination or ultrasonic radiation alone. Cell aggregation and sedimentation are significantly improved, enhancing the efficiency of subsequent water treatment processes such as coagulation, sedimentation, and filtration, and increasing disinfection safety.

[0031] The working process of this utility model is as follows: The mixing reaction tank 1 is set before the conventional water treatment process. The algae-containing raw water flows in from the inlet pipe 2. The chlorine oxidant dosing point 3 on the inlet pipe 2 is connected to the chlorinator 14 to continuously add chlorine according to the water volume. After the raw water enters the mixing reaction tank 1, the chlorinator and raw water are fully and evenly mixed by the mechanical stirring device 5. Under the action of the flow booster 6, the mixing effect of chlorine and algae cells is further enhanced. The algae-containing raw water is pretreated by ultrasound and chlorine oxidation in the mixing reaction tank 1. The pretreated water flows into the conventional water treatment process from the outlet pipe 9. When the inlet water quality is good and no additional pretreatment is required, the inlet valve 11 and the outlet valve 12 are closed, and the valve 13 on the bypass pipe 10 is opened, and the inlet water is discharged from the bypass pipe 10.

Claims

1. A device for the synergistic pretreatment of algal cells by ultrasound and chlorination to inactivate them, comprising a mixing reaction tank, an inlet pipe at one end of the mixing reaction tank, an inlet valve on the inlet pipe, a chlorination oxidant dosing point on the inlet pipe connected to a chlorinator, and an outlet pipe at the other end of the mixing reaction tank, the outlet pipe being equipped with an outlet valve, characterized in that: It also includes an ultrasonic radiation device, and the ultrasonic processing device includes a sound signal generator and a probe transducer. The sound signal generator and the probe transducer are electrically connected. The probe transducer is evenly arranged at the bottom of the reaction tank along the water flow direction and faces upward; or the probe transducer is arranged on both sides of the mixing reaction tank, and the arrangement position is below the liquid surface and facing the center of the water flow cross section.

2. The apparatus for synergistic pretreatment of algal cells by ultrasound and chlorination to inactivate them according to claim 1, characterized in that: The mixing reaction tank has several guide walls spaced alternately on both sides of the tank wall, which divide the mixing reaction tank into S-shaped water flow channels.

3. The apparatus for synergistic pretreatment of algal cells by ultrasound and chlorination to inactivate them according to claim 2, characterized in that: A mechanical stirring device is installed at the starting position of the water flow channel.

4. The apparatus for synergistic pretreatment of algal cells by ultrasound and chlorination to inactivate them according to claim 1, characterized in that: The mixing reaction tank is equipped with multiple drainage pipes.

5. The apparatus for synergistic pretreatment of algal cells by ultrasound and chlorination to inactivate them according to claim 1, characterized in that: Multiple flow promoters are distributed along the water flow direction within the mixing reaction tank.

6. The apparatus for synergistic pretreatment of algal cells by ultrasound and chlorination to inactivate them according to claim 1, characterized in that: It also includes a bypass pipe, one end of which is connected to the inlet pipe and the other end of which is connected to the outlet pipe. A valve is installed on the bypass pipe.

7. The apparatus for synergistic pretreatment of algal cells by ultrasound and chlorination to inactivate them according to claim 1, characterized in that: The raw water entering the mixing reaction tank from the inlet pipe has a residence time of 3 to 5 minutes in the mixing reaction tank.

8. The apparatus for synergistic pretreatment of algal cells by ultrasound and chlorination to inactivate them according to claim 1, characterized in that: The ultrasonic radiation frequency of the ultrasonic treatment device is 40 kHz to 120 kHz, and the ultrasonic radiation treatment time is not less than 3 min.

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