A system and method for treating recalcitrant wastewater

Abstract

The application discloses a kind of difficult degradation wastewater treatment systems, comprising: organic wastewater oxidation pond, wastewater inlet and oxygen inlet, organic wastewater oxidation pond top is provided with transparent glass cover, and transparent glass cover is provided with exhaust port;Organic wastewater oxidation pond is internally provided with scrap iron structure layer, and scrap iron structure layer is provided with upper releaser above, and lower releaser below;Organic wastewater oxidation pond is connected by pipeline circulation pump, and the bottom of organic wastewater oxidation pond is connected by water taking pipeline export pump;Wastewater inlet is connected by pipeline micro-bubble generator, upper releaser and lower releaser respectively;Oxygen inlet and circulation pump are connected by pipeline micro-bubble generator;Export pump is connected by pipeline export outlet.The application also discloses a kind of difficult degradation wastewater treatment method.The application solves the bottleneck and defect of prior art, resulting in multiple processing links, high cost, complex process, low efficiency, not complete, and secondary pollution problem.

Description

Technical Field

[0001] This invention relates to a system and method for treating recalcitrant wastewater. Background Technology

[0002] With the vigorous development of industries, agriculture, medical and health enterprises and the continuous improvement of people's living standards, the country has been increasing its efforts and attention to environmental protection, especially in the field of treatment and discharge of toxic, harmful and difficult-to-degrade polluting wastewater.

[0003] However, current domestic and international methods for treating this type of recalcitrant wastewater mainly include chemical flocculation, supercritical water oxidation, electrochemical oxidation, and one or more of these combined methods. While these methods effectively degrade some or most of the recalcitrant harmful and toxic substances in the wastewater, achieving certain results, they do not completely solve the problem and fail to meet the national standards for COD and ammonia nitrogen discharge. The main reasons for this are: first, the technology and system equipment are flawed, resulting in unstable operation, low efficiency, and difficulty in industrial production; second, the treatment process generates large amounts of chemically hazardous sludge and waste residue, requiring secondary or tertiary treatment, or being difficult to treat altogether (such as nuclear wastewater); and third, the high cost of raw materials increases treatment costs, with the cost per ton of water treated ranging from several hundred to several thousand RMB. In summary, the existing technology faces bottlenecks and poor economic benefits, making widespread adoption difficult.

[0004] Therefore, a system and method for treating recalcitrant wastewater are provided. Summary of the Invention

[0005] To address the aforementioned problems in the existing technology, this invention provides a system and method for treating recalcitrant wastewater, which solves the bottlenecks and defects of the existing technology that result in multiple treatment steps, high costs, complex processes, low efficiency, incomplete treatment, and secondary pollution.

[0006] The technical solution to achieve the above objectives is: A recalcitrant wastewater treatment system includes: an organic wastewater oxidation tank, a wastewater inlet, and an oxygen inlet. The top of the organic wastewater oxidation tank is equipped with a transparent glass cover, and an exhaust port is provided on the transparent glass cover; The organic wastewater oxidation tank is equipped with a waste iron scrap structure layer inside, with an upper release device above the waste iron scrap structure layer and a lower release device below it. The organic wastewater oxidation tank is connected to a circulation pump via a pipeline, and the bottom of the organic wastewater oxidation tank is connected to an external pump via a water intake pipeline. The wastewater inlet is connected to the microbubble generator, the upper releaser, and the lower releaser via pipelines. The oxygen inlet and the circulation pump are both connected to the microbubble generator via pipelines; The external pump is connected to the external output port via a pipeline.

[0007] Preferably, the organic wastewater oxidation tank is designed to be closed.

[0008] Preferably, the waste iron scrap structural layer is composed of Cu, Zn, Ni, Al, Mn, and Fe.

[0009] A second method for treating recalcitrant wastewater according to the present invention includes: Step S1: The recalcitrant organic wastewater is introduced into the upper and lower releasers through the wastewater inlet and pipeline under a certain flow rate and pressure. Step S2: Oxygen produced by the oxygen generator using air as raw material enters the microbubble generator through the oxygen inlet and pipeline under a certain flow rate and pressure. Step S3: Water from the organic wastewater oxidation tank is pumped into the microbubble generator through the circulation pump and fully mixed with the incoming oxygen. Step S4: The water mixed with oxygen is then mixed with wastewater and sent to the upper and lower releasers for zero-pressure release, generating a large number of oxygen bubbles and releasing wastewater. In step S5, a large number of oxygen bubbles and released wastewater come into full contact with the waste iron filings structure layer and undergo turbulent motion, forming multiple galvanic cells, which oxidize and degrade the organic pollutants in the wastewater, decomposing them into water, carbon dioxide, and nitrogen. In step S6, carbon dioxide and nitrogen are discharged through the exhaust port at the top of the organic wastewater oxidation tank, and the treated water is continuously output through the external output port connected to the external pump via the water intake pipeline at the bottom of the organic wastewater oxidation tank.

[0010] Preferably, in step S5, a large number of oxygen bubbles and the released wastewater come into full contact with the waste iron filings structural layer and undergo turbulent motion, forming multiple galvanic cells. Under the presence of oxygen, the electric field effect formed around the wastewater causes charged ions in the wastewater to move toward the opposite-charged electrode, resulting in a series of electrochemical oxidation reactions. Micro-oxygen bubbles continuously oxidize and degrade organic pollutants in the wastewater under the synergistic effect of the waste iron filings structural layer.

[0011] Preferably, in step S5, sunlight is simultaneously transmitted through the transparent glass cover to directly irradiate the surface of the wastewater, thereby using sunlight to assist in the oxidation and degradation of the wastewater, and using ultraviolet rays in sunlight to kill bacteria, viruses and other microorganisms in the wastewater.

[0012] Preferably, in step S6, the output water contains non-polluting suspended solids that are filtered through a filter.

[0013] Compared with existing technologies, the beneficial effects of this invention are as follows: This invention fully utilizes oxygen in the air as an oxidant, which, combined with multi-element metal scraps and sunlight, works synergistically to thoroughly oxidize and decompose pollutants in wastewater, achieving emission standards, while minimizing the cost of treating recalcitrant wastewater; the scrap iron reacts with organic chemicals in the wastewater medium via electrochemical reactions, decomposing and transforming organic pollutants into water, carbon dioxide, and nitrogen, achieving the goal of thoroughly degrading and removing organic pollutants from wastewater; the closed design of the organic wastewater oxidation tank ensures that the entire process of organic wastewater treatment is closed, preventing harmful odor pollution to the surrounding area and protecting the environment; secondly, sunlight passes through the transparent cover at the top of the wastewater oxidation tank and directly irradiates the surface of the wastewater, using sunlight to increase the wastewater temperature and accelerate the oxidation and degradation of wastewater, while the ultraviolet rays in sunlight can kill bacteria, viruses, and other microorganisms in the wastewater. Attached Figure Description

[0014] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1 This is a structural diagram of a recalcitrant wastewater treatment system according to the present invention; Figure 2 This is a structural diagram of the organic wastewater oxidation tank in this invention; Figure 3 This is a flowchart of a method for treating recalcitrant wastewater according to the present invention. Detailed Implementation

[0015] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] like Figure 1 , 2As shown, a recalcitrant wastewater treatment system includes: an organic wastewater oxidation tank 1, a wastewater inlet 2, and an oxygen inlet 3. The top of the organic wastewater oxidation tank 1 is equipped with a transparent glass cover 11, and an exhaust port 12 is provided on the transparent glass cover 11. The organic wastewater oxidation tank 1 has a waste iron filings structure layer 8 inside, with an upper release device 5 above the waste iron filings structure layer 8 and a lower release device 6 below it. The organic wastewater oxidation tank 1 is connected to a circulation pump 7 through a pipeline, and the bottom of the organic wastewater oxidation tank 1 is connected to an external pump 9 through a water intake pipeline. The wastewater inlet 2 is connected to a microbubble generator 4, the upper release device 5, and the lower release device 6 through pipelines. The oxygen inlet 3 and the circulation pump 7 are both connected to the microbubble generator 4 through pipelines. The external pump 9 is connected to an external outlet 10 through a pipeline.

[0017] In this embodiment, the organic wastewater oxidation tank 1 is designed to be sealed, and the organic wastewater is treated in a closed manner throughout the entire process, so that there is no harmful odor pollution to the surrounding area and the environment is protected. Sunlight passes through the transparent glass cover 11 on the top of the organic wastewater oxidation tank 1 and directly shines on the surface of the wastewater. The sunlight energy increases the temperature of the wastewater and plays an auxiliary role in accelerating the oxidation and degradation of the wastewater. At the same time, the ultraviolet rays in the sunlight can kill bacteria, viruses and other microorganisms in the wastewater.

[0018] In this embodiment, the waste iron scrap structure layer 8 is composed of Cu, Zn, Ni, Al, Mn, and Fe, with electrode potentials of +0.34V, -0.76V, -0.26V, -1.14V, -1.18V, and -0.44V, respectively. Therefore, there are potential differences between the metal elements, such as Cn and Fe 0.78V, Ni and Al 0.98V, etc. The larger the electrode potential difference between the metal elements, the more favorable it is for the electrochemical reaction between the metal and the scale-prone ions in the wastewater medium. When the wastewater medium comes into contact with the multi-element metal scrap, it forms a galvanic cell electrode system of the electrolyte solution. Utilizing the electric field effect formed around the multi-element metal scrap, the charged ions in the wastewater medium move towards the oppositely charged electrode to undergo a micro-electrolysis electrochemical reaction. The generated products, such as hydroxyl radicals (HO.) and atomic oxygen (O.), are strong oxidants that react with the organic chemical substances in the wastewater medium, decomposing and transforming organic pollutants into water, carbon dioxide, and nitrogen, thereby achieving the purpose of thoroughly degrading and removing organic pollutants from the wastewater.

[0019] like Figure 1-3 As shown, a method for treating recalcitrant wastewater includes: Step S1: The recalcitrant organic wastewater is introduced into the upper release device 5 and the lower release device 6 through the wastewater inlet 2 under a certain flow rate and pressure.

[0020] Step S2: Oxygen produced by the oxygen generator using air as raw material is introduced into the microbubble generator 4 through the oxygen inlet 3 and pipeline under a certain flow rate and pressure (the air pressure must be greater than the wastewater pressure, its volume flow rate is 5%-10% of the wastewater flow rate, and its oxygen concentration is 50%-90%).

[0021] In step S3, water from the organic wastewater oxidation tank 1 is pumped into the microbubble generator 4 via the circulation pump 7 and thoroughly mixed with the incoming oxygen.

[0022] In step S4, the water mixed with oxygen is then mixed with wastewater and sent to the upper releaser 5 and the lower releaser 6 for zero-pressure release, generating a large number of oxygen bubbles and releasing wastewater.

[0023] In step S5, a large number of oxygen bubbles and released wastewater come into full contact with the waste iron filings structure layer 8, creating turbulent motion and forming multiple galvanic cells. This oxidizes and degrades the organic pollutants in the wastewater, breaking them down into water, carbon dioxide, and nitrogen.

[0024] In the embodiment, a large number of oxygen bubbles and the released wastewater come into full contact with the waste iron filings structure layer 8 and undergo turbulent motion, forming multiple galvanic cells. Under the presence of oxygen, the electric field effect formed around the wastewater causes charged ions in the wastewater to move toward the opposite-charged electrode, resulting in a series of electrochemical oxidation reactions. Under the synergistic effect of the waste iron filings structure layer 8, the micro-oxygen bubbles continuously oxidize and degrade the organic pollutants in the wastewater.

[0025] In this embodiment, sunlight is simultaneously transmitted through the transparent glass cover 11 to directly irradiate the surface of the wastewater. The sunlight energy is used to increase the temperature of the wastewater, which helps to accelerate the oxidation and degradation of the wastewater. The ultraviolet rays in the sunlight energy are used to kill bacteria, viruses and other microorganisms in the wastewater.

[0026] In step S6, carbon dioxide and nitrogen are discharged through the exhaust port 12 at the top of the organic wastewater oxidation tank 1, and the treated water is continuously output through the water intake pipeline at the bottom of the organic wastewater oxidation tank 1 and the external output port 10 connected to the external pump 9.

[0027] In this embodiment, the output water contains non-polluting suspended solids that are filtered through a filter and require no further treatment.

[0028] Finally, it should be noted that the above are merely preferred embodiments of the present invention and are 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. A wastewater treatment system for recalcitrant wastewater, characterized in that, include: Organic wastewater oxidation pond (1), wastewater inlet (2) and oxygen inlet (3). The top of the organic wastewater oxidation tank (1) is provided with a transparent glass cover (11), and an exhaust port (12) is provided on the transparent glass cover (11). The organic wastewater oxidation tank (1) is provided with a waste iron filings structure layer (8), with an upper release device (5) above the waste iron filings structure layer (8) and a lower release device (6) below it. The organic wastewater oxidation tank (1) is connected to the circulation pump (7) through a pipeline, and the bottom of the organic wastewater oxidation tank (1) is connected to the external pump (9) through a water intake pipeline. The wastewater inlet (2) is connected to the microbubble generator (4), the upper releaser (5) and the lower releaser (6) respectively through pipelines. The oxygen inlet (3) and the circulation pump (7) are both connected to the microbubble generator (4) through pipelines. The external pump (9) is connected to the external output port (10) through a pipeline; The organic wastewater oxidation tank (1) is designed to be closed. The waste iron scrap structure layer (8) is composed of Cu, Zn, Ni, Al, Mn and Fe.

2. A method for treating recalcitrant wastewater based on the recalcitrant wastewater treatment system according to claim 1, characterized in that, include: Step S1: The recalcitrant organic wastewater is introduced into the upper release device (5) and the lower release device (6) through the wastewater inlet (2) under a certain flow rate and pressure. Step S2: Oxygen produced by the oxygen generator using air as raw material enters the microbubble generator (4) through the oxygen inlet (3) and pipeline under a certain flow rate and pressure. Step S3: Water in the organic wastewater oxidation tank (1) is sent to the microbubble generator (4) through the circulation pump (7) and fully mixed with the incoming oxygen; Step S4: The water mixed with oxygen is then mixed with wastewater and sent to the upper releaser (5) and lower releaser (6) for zero-pressure release, generating a large number of oxygen bubbles and releasing wastewater. In step S5, a large number of oxygen bubbles and released wastewater come into full contact with the waste iron filings structure layer (8) and undergo turbulent motion, forming multiple galvanic cells, oxidizing and degrading the organic pollutants in the wastewater, and decomposing them into water, carbon dioxide and nitrogen. In step S6, carbon dioxide and nitrogen are discharged through the exhaust port (12) at the top of the organic wastewater oxidation tank (1), and the treated water is continuously output through the water intake pipeline at the bottom of the organic wastewater oxidation tank (1) and the external output port (10) connected to the external output pump (9). In step S5, a large number of oxygen bubbles and released wastewater come into full contact with the waste iron filings structure layer (8) and undergo turbulent motion to form multiple galvanic cells. Under the presence of oxygen, the electric field effect formed around the wastewater causes charged ions in the wastewater to move toward the opposite-charged electrode and undergo a series of electrochemical oxidation reactions. Micro-oxygen bubbles continuously oxidize and degrade organic pollutants in the wastewater under the synergistic effect of the waste iron filings structure layer (8). In step S5, sunlight is simultaneously transmitted through the transparent glass cover (11) to directly irradiate the surface of the wastewater, thereby using sunlight to assist in the oxidation and degradation of the wastewater, and using ultraviolet rays in sunlight to kill bacteria, viruses and microorganisms in the wastewater.

3. The method for treating recalcitrant wastewater according to claim 2, characterized in that, In step S6, the output water contains non-polluting suspended solids that are filtered through a filter.

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