Electrolytic biofilter system for rapid treatment of overflow pollution

Abstract

The utility model relates to the technical field of sewage treatment equipment, in particular to an electrolytic biological filter system for rapid treatment of overflow pollution, which comprises a bioelectrochemical system and a biological aerated filter system, the bioelectrochemical system comprises a tank body I, a biological anode and a biological cathode are arranged in the tank body I, and the biological anode and the biological cathode are arranged in the tank body II. The biological anode and the biological cathode are connected to a power supply, the biological aerated filter system comprises a tank body II, sewage treated by the tank body I enters the tank body II, an aeration device, a filtering device and a clear water outlet device are arranged in the tank body II, and the biological electrochemical system is coupled with the biological aerated filter through the aeration device, the filtering device and the clear water outlet device. The electrolytic biological filter system for rapidly treating overflow pollution is formed, the rapid electron transfer characteristic of a bioelectrochemical system is fully utilized, the denitrification rate of the biological aerated filter is increased, the treatment time can be greatly shortened under the same denitrification requirement, and the effect of rapidly treating overflow pollution in emergency is achieved.

Description

TECHNICAL FIELD

[0001] The utility model relates to sewage treatment equipment technical field especially face the electrolytic biological filter system of quick processing of overflow pollution. BACKGROUND

[0002] In order to deal with the overflow pollution problem in flood season, researchers have proposed many rapid treatment methods, such as storage, sedimentation, filtration, biological filter, artificial wetland, etc. The main purpose of these treatment methods is to quickly treat suspended solids, organic matter, etc. in water to meet the requirements of discharge into the river and reduce the impact of surface source caused by rainfall overflow. However, due to the short treatment time, the treatment unit itself only has a single performance, which makes it impossible for a single treatment method to guarantee the simultaneous removal of nitrogen, phosphorus, organic matter, suspended solids and other pollutants to achieve the ideal level. Among them, the biological aerated filter is a wastewater treatment technology that integrates physical, biological and chemical reaction processes. It has certain removal performance for nitrogen, phosphorus, organic matter and suspended solids in wastewater. It can be praised in terms of suspended solids and organic matter removal, but due to the low biodegradability of organic matter in overflow sewage, large treatment load and overall aerobic environment, its biochemical removal efficiency of refractory organic matter, nitrogen, phosphorus and other pollutants is low. Therefore, it is imperative to improve and upgrade the existing methods.

[0003] In recent years, biological electrochemical systems have received extensive attention due to their sustainability in energy and chemical production and high efficiency in water treatment. The characteristics of biological electrochemical systems, such as accelerating electron transfer, promoting the transformation of nitrogen, phosphorus and other pollutants, and improving the biodegradability of organic matter, make them highly applicable in the rapid treatment of overflow pollution during the flood season. The combination of biological electrochemical systems and biological filters (electrolytic biological filter system) can simultaneously achieve high suspended solids removal performance of biological filters and high nitrogen, phosphorus and organic matter reduction efficiency of biological electrochemical systems. By utilizing the characteristics of biological electrochemical processes to accelerate electron transfer and pollutant transformation, the treatment time of overflow pollution during the flood season can be greatly reduced, which meets the rapid treatment needs of large water volume and short-term pollution during the flood season. This technology can effectively reduce the overflow pollution during the flood season and achieve rapid purification of nitrogen, phosphorus, organic matter and suspended solids in flood season rainwater and overflow sewage. UTILITY MODEL CONTENTS

[0004] The utility model aims at overcoming the deficiencies in the prior art and provides an electrolytic biological filter system for rapid treatment of overflow pollution.

[0005] The utility model is implemented by the following technical solutions: an electrolytic biological filter system for rapid treatment of overflow pollution, comprising a biological electrochemical system and an aerated biological filter system,

[0006] The bioelectrochemical system includes a tank, within which a bioanode and a biocathode are disposed, and the bioanode and biocathode are connected to a power source.

[0007] The aerated biological filter system includes a second tank. Wastewater treated in the first tank enters the second tank. The second tank is equipped with an aeration device, a filtration device, and a clear water outlet device.

[0008] Furthermore, both the bioanode and the biocathode include a conductive mesh cage, and an electrode body is disposed inside the conductive mesh cage.

[0009] Furthermore, a reference electrode is disposed between the bioanode and the biocathode.

[0010] Furthermore, a sludge storage tank is provided at the bottom of the pool body.

[0011] Furthermore, the filtration device includes a coarse filter layer and a fine filter layer arranged sequentially along the sewage flow direction.

[0012] Furthermore, it also includes a backwashing device, which includes a backwashing pump located at the bottom of the second pool body, and the backwashing pump is connected to a clean water outlet device.

[0013] Furthermore, the backwashing device includes a clear water tank connected to the clear water outlet device, and the backwashing pump is connected to the clear water tank.

[0014] Furthermore, the water outlet device includes an overflow trough disposed at the upper end of the second pool body, the overflow trough being distributed around the upper end of the second pool body.

[0015] The beneficial effects of this utility model are as follows:

[0016] 1. By coupling the bioelectrochemical system with the aerated biological filter, an electrolytic biological filter system for rapid treatment of overflow pollution is formed. This fully utilizes the rapid electron transfer characteristics of the bioelectrochemical system to improve the denitrification rate of the aerated biological filter. Under the same denitrification requirements, the treatment time can be greatly reduced, achieving the effect of rapid emergency treatment of overflow pollution.

[0017] 2. Make full use of bioelectrochemical processes to break down the degradation barriers of recalcitrant organic matter, degrade macromolecular organic matter into small molecule organic matter with high bioavailability, improve the B / C ratio of wastewater, and enhance denitrification performance.

[0018] 3. Utilize the anodic deposition of iron ions in the bioelectrochemical system to enhance the flocculation and removal effect of the system on phosphorus and suspended solids;

[0019] 4. The front-end bioelectrochemical system not only serves as an enhanced treatment unit for the electrolytic biological filter system, but also acts as a primary sedimentation tank to preliminarily precipitate solid matter in the raw water to reduce the risk of clogging in the subsequent aerated biological filter. It also precipitates and clarifies the backwash effluent during backwashing. Attached Figure Description

[0020] Figure 1 This is a schematic diagram showing the connection relationship of each component in Example 1;

[0021] Figure 2 This is a schematic diagram of the connection relationship between the components in Example 2.

[0022] The components include: 1. Biomotor; 2. Tank body 1; 3. DC regulated power supply; 4. Computer; 5. Resistor; 6. Multi-channel voltage data acquisition device; 7. Sludge storage tank; 8. Sludge discharge pipe; 9. Reference electrode; 10. Lightweight ceramsite layer; 11. Water outlet switch; 12. Water outlet pipe; 13. Gravel support layer; 14. Aeration blower; 15. Clear water tank inlet pipe; 16. Backwash air path; 17. Water distribution trough; 18. Clear water tank; 19. Backwash pump; 20. Water distribution trough inlet switch; 21. Backwash outlet switch. Detailed Implementation

[0023] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" 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 based on the specific circumstances.

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0025] Example 1

[0026] Example 1

[0027] like Figure 1 As shown, an electrolytic biofilter system for rapid treatment of overflow pollution includes a bioelectrochemical system and an aerated biofilter system.

[0028] The bio-electrochemical system comprises a pool body 1, the lower end of the pool body 2 is an upwardly open cone, the bottom is a plane, and a sludge discharge pipe 8 is installed on the bottom surface to precipitate solid substances in raw water and discharge the system, reduce the suspended substance concentration of the inlet water of the back-end biological aerated filter to reduce the risk of blockage, and the bio-electrode installed in the pool body 1 comprises a biological anode and a biological cathode, wherein the biological anode is close to the side of the sewage inlet water, the biological anode and the biological cathode both comprise a conductive mesh cage, the conductive mesh cage is made of multiple layers of stainless steel punched mesh, the aperture of the stainless steel punched mesh is 0.3 cm, the hole spacing is 0.1 cm, and the thickness is 3 mm, which surrounds a conductive mesh cage with a thickness of 10 cm, the conductive mesh cage is in the shape of a cuboid, the conductive mesh cage is filled with an electrode main body, the electrode main body is composed of activated carbon blocks with a diameter of 0.5-1 cm, the stainless steel punched mesh mainly serves as a framework and a current collector, the activated carbon blocks are the main body of the biological electrode, and serve to enrich electrically active microorganisms, remove nitrogen and phosphorus, the distance between the biological anode and the biological cathode is 10 cm, and the biological anode and the biological cathode are vertically and parallelly arranged, the biological anode is close to the side of the sewage inlet water, the biological anode and the biological cathode are connected to a power supply, specifically, the power supply is a direct-current stabilized power supply with an output voltage precision of 0.01 V, the direct-current stabilized power supply is connected to the biological anode and the biological cathode through an external circuit, so that a potential difference is formed between the biological anode and the biological cathode, the direct-current stabilized power supply is also connected with a resistor, the resistor 5 is a cement resistor with good stability, the resistivity is 50-100 Ω, a reference electrode is also installed between the biological anode and the biological cathode, the reference electrode is an Ag / AgCl2 standard reference electrode, and is connected to a negative pole channel of a multi-channel voltage data collector 6, at the same time, the biological anode and the biological cathode are connected to two positive pole channels of the multi-channel voltage data collector 6 to record the potential of the biological anode and the biological cathode, one pair of positive and negative pole channels of the multi-channel voltage data collector 6 are connected to the two ends of the resistor 5 to monitor the real-time voltage on the resistor and calculate the current data, the data output port of the multi-channel voltage data collector 6 is connected to a computer 4 to be visualized to present real-time monitoring data, a water distribution groove inlet pipe is installed on the pool body 1 below the biological electrode, and a water distribution groove inlet switch is installed, sewage enters the pool body 1 from the upper end of the pool body 1, is treated by the biological electrode, and then flows into the pool body 2 through the water distribution groove inlet pipe.

[0029] The aerated biological filter system comprises a pool body two, in the embodiment, the pool body one and the pool body two are separated by a partition, the pool body two is internally provided with an aeration device, a filtering device and a clear water outlet device, specifically, a water distribution groove is obtained by separating the lower end of the pool body two through a horizontal supporting plate, water distribution holes are processed on the supporting plate, and the water is uniformly distributed to the filtering device, the filtering device is installed on the upper end of the supporting plate and comprises a coarse filter layer and a fine filter layer which are sequentially distributed along the sewage flow direction, wherein the coarse filter layer comprises a gravel supporting layer, the diameter of the gravel is 1-2 cm, and one or more of the same particle size of pebbles, quartz sand, zeolite and ceramsite can be selected and mixed, and the fine filter layer comprises a light ceramsite layer, the diameter of the light ceramsite is 0.5-1 cm, and the fine filter layer is a main reaction layer.

[0030] The aeration device comprises an aeration fan and an aeration pipe, the aeration fan is installed on the outer side of the pool body two, the aeration pipe extends into the gravel supporting layer, and aeration holes are processed on the aeration pipe, so that the air is uniformly distributed into the gravel supporting layer.

[0031] The clear water outlet device comprises an overflow tank which is installed on the upper end of the pool body two and is distributed around the upper end of the pool body two, the clear water obtained by the filtering device flows into the overflow tank, the overflow tank is connected with a water outlet pipe, and a water outlet switch is installed on the water outlet pipe.

[0032] The backwashing device further comprises a backwashing pump which is connected to the bottom of the pool body two, the backwashing pump is connected to the clear water outlet device, specifically, the backwashing device comprises a clear water tank which is connected to the clear water outlet device, the clear water tank is distributed at the lower end of the water distribution groove and is sealed and isolated from the water distribution groove, the backwashing pump is connected to the clear water tank, the backwashing pump is a submersible pump and is installed in the clear water tank, the water outlet pipe of the backwashing pump extends into the water distribution groove, the clear water tank and the water outlet pipe are connected through a clear water tank water inlet pipe, the overflow tank is further connected with a backwashing water outlet pipe, a backwashing water outlet switch is installed on the backwashing water outlet pipe, and the water outlet of the backwashing water outlet pipe extends into the pool body one.

[0033] In addition, the aeration fan is further connected with a branch pipe to the water distribution groove, so that the water distribution groove is aerated and disturbed during the backwashing process, and the water distribution groove is also efficiently washed.

[0034] A running method of an electrolytic biological filter system for rapid treatment of overflow pollution, comprising the following steps,

[0035] S1, pretreatment, inoculate activated sludge from the anoxic treatment section of a sewage treatment plant into pool body one and pool body two, the inoculation amount is the submerged biological anode, biological cathode, gravel support layer and lightweight ceramsite layer, control the concentration of activated sludge to be 3 g / L, and then ensure the fluidity, power on the biological anode and biological cathode, maintain a voltage of 0.1 V, and continue for 20 days, in the process, the biological anode and biological cathode are subjected to microbial enrichment, the biological anode is enriched with organic matter degrading bacteria and electrically active bacteria such as Arthrobacter and Geobacter; the biological cathode is enriched with denitrifying bacteria and electrically active bacteria such as Caldilinea, Denitromonas and Thillbacilius, and the most dominant bacteria Arthrobacter and Thillbacilius account for 18.73% and 4.80% of the corresponding electrodes respectively. The voltage is maintained at 0.1 V to utilize the microbial selection characteristics of electrochemistry and enrich electrically active bacteria, and too high a voltage (such as 0.5 V) is easy to cause oxidation of the iron electrode, resulting in a positive shift of the electrode potential, making the cathode potential too high, and the denitrification environment cannot be formed, and the lightweight ceramsite layer forms the main reaction layer, and the biological membrane is formed on the surface of the filler of the gravel support layer;

[0036] S2, start-up, installed beside the overflow outlet of the combined rainwater system, a water inlet pool is arranged in front of the system, the overflow pipeline of the combined rainwater pipe network is connected to the water inlet pool, the overflow sewage flows into pool body one from the water inlet pool, the voltage is adjusted to 0.5 V, sewage is introduced into pool body one, and the aeration device is started at the same time, and the effluent of the effluent device is detected;

[0037] S3, Operation: Wastewater and effluent are monitored. The system's treatment effectiveness is assessed by monitoring ammonia nitrogen, nitrate nitrogen, total nitrogen, total phosphorus, total suspended solids, and chemical oxygen demand. The voltage is maintained at 0.5V, and the system begins normal operation. Electroactive microorganisms enriched on the bioanode decompose organic matter and transfer the generated electrons to the biocathode. Electroactive microorganisms on the biocathode acquire electrons and reduce nitrate nitrogen in the wastewater near the biocathode to nitrogen gas. During this process, the potential of the biocathode relative to the reference electrode is maintained at -0.5 to -0.6 V, and the Ag / AgCl2 solid standard reference electrode relative to the standard hydrogen reference electrode is +0.199 V. V, relative to the reference electrode, the bioanode is maintained below 0V. Above 0V, the bioanode is prone to iron electrode oxidation, leading to a gradual increase in the anode potential, which in turn increases the cathode potential, ultimately preventing the formation of a denitrification environment near the electrode. During operation, wastewater enters the tank through the inlet pipe. The wastewater first passes through the bioanode, where electroactive microorganisms enriched in the bioanode decompose organic matter and transfer the generated electrons to the bioelectrode. These electrons are then transferred to the biocathode through an external circuit. Electroactive microorganisms on the biocathode acquire electrons and reduce nitrate nitrogen in the wastewater near the biocathode to nitrogen gas. This process simultaneously accelerates the removal of organic matter and nitrate nitrogen. In addition, under the catalysis of microorganisms, the biocathode converts protons in the water into H2, and under the action of the cathode microorganisms, a hydrogen autotrophic denitrification process occurs, further intensifying the process. The removal of nitrate nitrogen; on the bioanode, the electrochemical process catalyzed by microorganisms initially degrades the recalcitrant organic pollutants into smaller organic molecules that are more easily utilized by microorganisms, increasing the B / C ratio of the influent to the next stage tank, which is conducive to the biochemical reaction. The iron ions released in the system cause the phosphorus and solid matter in the sewage to flocculate and settle to the bottom of the bioelectrochemical system tank, and are transported to the sludge storage tank 7 by the bottom sludge discharge pipe 8. The effluent from the bioelectrochemical system enters the aerated biological filter tank from the water distribution tank 17. The sewage passes through the aerated aerobic zone, and the ammonia nitrogen in the sewage is oxidized to nitrate nitrogen through nitrification. Then, in the anaerobic and anoxic microenvironment formed by the light ceramic filter layer, the organic matter and nitrate nitrogen are simultaneously reduced through denitrification, and the system is released in the form of nitrogen gas. The effluent then flows into the clear water tank 18 or is further discharged into natural water bodies.

[0038] S4, Backwashing: When the electrolytic biological filter system for rapid overflow pollution treatment has been running for a period of time, and the stable water level rise in the bioelectrochemical system indicates increased head loss in the aerated biological filter influent, severe blockage has occurred, and it cannot perform its filtration function normally, the backwashing process is initiated. At the start of the backwashing process, wastewater influent is stopped, and the influent and effluent switches 20 and 11 of the aerated biological filter cloth's water tank, as well as the aeration pipe, are closed; the backwashing air circuit 16 is opened, with an air flow rate of 10-15 L / (m³). 2Air rinsing is performed at an intensity of *s) for 3-5 minutes, followed by simultaneous opening of backwash water path 19 and backwash outlet switch 21 to pump clean water from clean water tank 18 at a rate of 5-10 L / (m³). 2 The air-water combined backwash is performed at the intensity of *s) for 5-10 minutes. Finally, the backwash air path 16 is closed, and the water is washed for 5-10 minutes. The backwash water flows into the first tank through the backwash outlet 21. After sedimentation, the sediment enters the sludge storage tank 7 through the sludge discharge pipe 8. This process can greatly improve the simultaneous removal of recalcitrant organic matter, nitrates, phosphorus and ammonia nitrogen in the overflow polluted water.

[0039] After backwashing is complete, return to step S1.

[0040] The operation method of the electrolytic biological filter system for rapid treatment of overflow pollution provided in this embodiment is shown in Appendix Table 1.

[0041] Appendix 1

[0042]

[0043] Table 1 shows the control group's test data after 24 hours of operation without the bioanode and biocathode activated. In comparison, the pollutant removal performance of this system is significantly improved compared to standalone aerated biological filter technology. For the same denitrification requirements, this system can shorten the treatment time. The system's nitrate removal performance is significantly enhanced, and the B / C ratio of the effluent from tank one increases by 32%. During the testing process, it was found that maintaining the electrode activity of the microbial electrochemical system in tank one and enriching and cultivating electroactive bacteria are crucial. The electron transfer between microorganisms and electrodes by electroactive bacteria is a prerequisite for the enhanced pollutant removal process of microbial electrochemistry. Therefore, the startup process of this system is critical. In contrast, standalone aerated biological filter technology, due to the aeration process... The presence of oxygen makes its denitrification environment poor, hindering the removal of nitrate nitrogen. To improve the nitrate nitrogen removal rate, dissolved oxygen content must be controlled. However, achieving sufficient dissolved oxygen for ammonia oxidation and COD oxidation, while simultaneously creating an anaerobic or hypoxic environment conducive to denitrification in a single device, presents significant technical challenges. This is because the contact time between wastewater and packing material, internal flow patterns, and oxygen transfer are complex and variable. Therefore, even with precise control, maintenance is extremely difficult. This system, however, separates the anaerobic / hypoxic processes from the aerobic / hypoxic processes into two separate tanks, creating conditions favorable to each process, effectively avoiding the aforementioned problems.

[0044] Example 2

[0045] like Figure 2As shown, an electrolytic biological filter system for rapid treatment of overflow pollution differs from Embodiment 1 in that, in Tank 1, wastewater flows into Tank 1 from below the bioelectrode and flows out of Tank 1 from above the bioelectrode. The bioanode and biocathode are horizontally parallel, with the bioanode located on the lower side, allowing the wastewater to pass through the bioanode and biocathode more effectively in sequence. The effluent from Tank 1 enters Tank 2 after passing through the overflow trough, and then flows from top to bottom through the lightweight ceramsite layer and gravel support layer before flowing into the clear water tank and then being discharged. In this embodiment, the water distribution trough is retained, which mixes with the airflow in the backwashing air path during the backwashing process to backwash the lightweight ceramsite layer and gravel support layer. The backwash outlet pipe is not connected to Tank 1, but to a separate wastewater tank (not shown in the figure). Compared with Embodiment 1, this embodiment can remove suspended solids better. The disadvantage is that the upward flow of wastewater in Tank 1 causes greater disturbance to the bioanode, requiring regular maintenance.

[0046] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An electrolytic biological filter system for rapid treatment of overflow pollution, characterized in that, Including bioelectrochemical systems and aerated biological filter systems, The bioelectrochemical system includes a tank, within which a bioanode and a biocathode are disposed, and the bioanode and biocathode are connected to a power source. The aerated biological filter system includes a second tank. Wastewater treated in the first tank enters the second tank. The second tank is equipped with an aeration device, a filtration device, and a clear water outlet device.

2. The electrolytic biological filter system for rapid treatment of overflow pollution according to claim 1, characterized in that, Both the bioanode and the biocathode include a conductive mesh cage, and an electrode body is disposed inside the conductive mesh cage.

3. The electrolytic biological filter system for rapid treatment of overflow pollution according to claim 1, characterized in that, A reference electrode is provided between the bioanode and the biocathode.

4. The electrolytic biological filter system for rapid treatment of overflow pollution according to claim 1, characterized in that, A mud storage tank is provided at the bottom of the pool.

5. The electrolytic biological filter system for rapid treatment of overflow pollution according to claim 1, characterized in that, The filtration device includes a coarse filter layer and a fine filter layer arranged sequentially along the sewage flow direction.

6. The electrolytic biological filter system for rapid treatment of overflow pollution according to claim 1, characterized in that, It also includes a backwashing device, which includes a backwashing pump located at the bottom of the second pool body, and the backwashing pump is connected to a clean water outlet device.

7. The electrolytic biological filter system for rapid treatment of overflow pollution according to claim 6, characterized in that, The backwashing device includes a clear water tank connected to the clear water outlet device, and the backwashing pump is connected to the clear water tank.

8. The electrolytic biological filter system for rapid treatment of overflow pollution according to claim 1, characterized in that, The water outlet device includes an overflow trough located at the upper end of the second pool body, and the overflow trough is distributed around the upper end of the second pool body.

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