Denitrifying bacteria selective biofilm carrier and sewage total nitrogen treatment method

Abstract

The present disclosure provides a method for treating total nitrogen in sewage, comprising the following steps: obtaining a support line and a plurality of denitrifying bacteria adsorption belt rings, and then wrapping a plurality of the denitrifying bacteria adsorption belt rings on the support line to obtain a denitrifying bacteria selective biofilm carrier. The polluted water body is subjected to a treatment for reducing the dissolved oxygen content. The denitrifying bacteria selective biofilm carrier is placed in the polluted water body after the treatment for reducing the dissolved oxygen content, and the position of the denitrifying bacteria selective biofilm carrier in the polluted water body is marked as a total nitrogen adsorption zone. The polluted water body is subjected to a total nitrogen adsorption treatment by using a plurality of the denitrifying bacteria adsorption belt rings. Denitrifying bacteria in the polluted water body are attracted by the total nitrogen adsorption zone. The organic nitrogen and inorganic nitrogen in the total nitrogen adsorption zone are subjected to a denitrification reaction by the denitrifying bacteria on the denitrifying bacteria selective biofilm carrier. The denitrifying adsorption belt ring is formed by twisting a plurality of total nitrogen adsorption wires.

Description

Technical Field

[0001] The present disclosure relates to the field of sewage, and in particular to a denitrifying bacteria selective biofilm carrier and a method for treating total nitrogen in sewage. Background Art

[0002] With the acceleration of industrialization and the intensification of aquaculture, nitrite and nitrogen pollution in water bodies not only affects the survival of aquatic organisms, but also leads to eutrophication and disrupts the ecological balance. To reduce the total nitrogen index in water bodies, biofilm carriers are often used to provide a loading space for denitrifying bacteria, which then reduce the total nitrogen index.

[0003] However, traditional biofilm carriers have poor sewage treatment effects when applied to micro-polluted water bodies such as rivers, lakes, and aquaculture water after nitrification. Specifically, the ammonia nitrogen concentration of such micro-polluted water bodies is low, and the total nitrogen concentration after nitrification is also relatively low (generally 0mg / L to 40mg / L), and the inorganic nitrogen and organic nitrogen in the water body are dispersed in various areas of the water body, but the position of the biofilm carrier is fixed, and the traditional biofilm carrier only has a load function, which also leads to limited inorganic nitrogen and organic nitrogen content in the area where the biofilm carrier is located, resulting in a small amount of denitrifying bacteria on the biofilm carrier, resulting in poor total nitrogen treatment effect of the biofilm carrier in micro-polluted water bodies. Summary of the Invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a denitrifying bacteria selective biofilm carrier and a sewage total nitrogen treatment method that can improve the total nitrogen treatment effect.

[0005] The purpose of this disclosure is achieved through the following technical solutions:

[0006] A method for treating total nitrogen in sewage, comprising the following steps:

[0007] Obtaining a support line and a plurality of denitrifying bacteria adsorption rings, and then coating the support line with the plurality of denitrifying bacteria adsorption rings to obtain a denitrifying bacteria selective biofilm carrier;

[0008] Treat polluted water bodies to reduce dissolved oxygen;

[0009] placing the denitrifying bacteria selective biofilm carrier in the polluted water body after the dissolved oxygen reduction treatment, and marking the position of the denitrifying bacteria selective biofilm carrier in the polluted water body as a total nitrogen adsorption zone;

[0010] The polluted water body is subjected to total nitrogen adsorption treatment by a plurality of denitrifying bacteria adsorption belt rings, so that the organic nitrogen and inorganic nitrogen free in the polluted water body are concentrated in the total nitrogen adsorption zone;

[0011] Attracting denitrifying bacteria in the polluted water body through the total nitrogen adsorption zone, so that the denitrifying bacteria adhere to a plurality of the denitrifying bacteria adsorption belt rings;

[0012] The denitrifying bacteria on the denitrifying bacteria selective biofilm carrier perform denitrification reaction on the organic nitrogen and inorganic nitrogen in the total nitrogen adsorption area;

[0013] The denitrification adsorption belt ring is formed by twisting a plurality of total nitrogen adsorption wires.

[0014] In one embodiment, the support wire band is formed by winding and twisting a plurality of shaping wires.

[0015] In one embodiment, the total nitrogen adsorption thread includes a fiber thread and a total nitrogen adsorption powder uniformly adhered to the surface of the fiber thread by an adhesive.

[0016] In one embodiment, the total nitrogen adsorption powder includes activated carbon, sulfur, iron powder and iron sulfide.

[0017] In one embodiment, the mass ratio of the activated carbon, the sulfur, the iron powder and the iron sulfide powder is (10-20): (5-8): (0.5-2): (5-8).

[0018] In one embodiment, the fiber filaments are a combination of one or more of nylon fiber filaments, polypropylene fiber filaments, carbon fiber filaments and aramid fiber filaments.

[0019] In one embodiment, the specific steps of treating the polluted water body to reduce the dissolved oxygen content are:

[0020] The water inflow of the polluted water body is increased, and the polluted water body is stirred by a stirring system.

[0021] In one embodiment, the dissolved oxygen content of the polluted water body after the dissolved oxygen reduction treatment is 0 mg / L to 0.2 mg / L.

[0022] In one embodiment, before the step of reducing the dissolved oxygen content of the polluted water, the method for treating total nitrogen in sewage further comprises the following steps:

[0023] The polluted water body is subjected to nitrification treatment through a nitrification system.

[0024] A denitrification selective biofilm carrier is used in the method for treating total nitrogen in wastewater described in any of the above embodiments.

[0025] Compared with the prior art, the present disclosure has at least the following advantages:

[0026] Since the denitrifying bacteria adsorption belt ring is formed by winding and twisting a number of total nitrogen adsorption wires, the denitrifying bacteria adsorption belt ring forms a total nitrogen adsorption field, and a number of denitrifying bacteria adsorption belt rings are coated on the support belt to obtain a denitrifying bacteria selective biofilm carrier, so that the denitrifying bacteria selective biofilm carrier forms a total nitrogen adsorption area with a larger adsorption intensity. In this way, when the polluted water body is subjected to total nitrogen adsorption treatment through a number of denitrifying adsorption belt rings, the organic nitrogen and inorganic nitrogen free in the polluted water body can be concentrated in the total nitrogen adsorption area, thereby increasing the total nitrogen concentration in the total nitrogen adsorption area. The denitrifying bacteria in the polluted water body are attracted to the total nitrogen adsorption zone and attached to several denitrifying bacteria adsorption rings. The high total nitrogen concentration creates sufficient nutritional conditions for the denitrifying bacteria in the total nitrogen adsorption zone, prompting the denitrifying bacteria on the denitrification selective biofilm carrier to continuously absorb organic nitrogen and inorganic nitrogen for denitrification reaction treatment, which can enable the denitrifying bacteria to continue to grow and multiply and become the dominant bacteria species in the polluted water body. At the same time, it can effectively reduce the total nitrogen concentration in the polluted water body, and greatly improve the total nitrogen treatment effect of the denitrification selective biofilm carrier in slightly polluted water bodies. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present disclosure and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 This is a flow chart of the total nitrogen treatment method for wastewater;

[0029] Figure 2 This is a physical picture of the selective biofilm carrier for denitrifying bacteria;

[0030] Figure 3 This is a physical picture of the braided biofilm carrier in the prior art. DETAILED DESCRIPTION

[0031] To facilitate understanding of the present disclosure, a more comprehensive description of the present disclosure will be provided below with reference to the accompanying drawings. The accompanying drawings illustrate preferred embodiments of the present disclosure. However, the present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the disclosure.

[0032] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly attached to the other element or there may be an intermediate element. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only implementation methods.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this disclosure pertains. The terms used herein in the specification of this disclosure are intended only to describe specific embodiments and are not intended to limit this disclosure. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0034] The present disclosure provides a method for treating total nitrogen in wastewater, comprising the following steps: obtaining a support line and a plurality of denitrifying bacteria adsorption belt rings, and then wrapping the support line with a plurality of the denitrifying bacteria adsorption belt rings to obtain a denitrifying bacteria selective biofilm carrier. The polluted water body is subjected to a treatment to reduce the dissolved oxygen content. The denitrifying bacteria selective biofilm carrier is placed in the polluted water body that has undergone the treatment to reduce the dissolved oxygen content, and the position of the denitrifying bacteria selective biofilm carrier in the polluted water body is marked as a total nitrogen adsorption zone. The polluted water body is subjected to a total nitrogen adsorption treatment using the plurality of the denitrifying bacteria adsorption belt rings, so that the organic nitrogen and inorganic nitrogen free in the polluted water body are concentrated in the total nitrogen adsorption zone. The denitrifying bacteria in the polluted water body are attracted by the total nitrogen adsorption zone, causing the denitrifying bacteria to attach to the plurality of the denitrifying bacteria adsorption belt rings. The denitrifying bacteria on the denitrifying bacteria selective biofilm carrier undergo a denitrification reaction on the organic nitrogen and inorganic nitrogen in the total nitrogen adsorption zone. The denitrification adsorption belt ring is formed by twisting a plurality of total nitrogen adsorption wires.

[0035] The above-mentioned method for treating total nitrogen in sewage, since the denitrifying bacteria adsorption belt ring is formed by winding and twisting a number of total nitrogen adsorption wires, the denitrifying bacteria adsorption belt ring forms a total nitrogen adsorption field, and a number of denitrifying bacteria adsorption belt rings are coated on the support belt to obtain a denitrifying bacteria selective biofilm carrier, so that the denitrifying bacteria selective biofilm carrier forms a total nitrogen adsorption area with a relatively large adsorption intensity. In this way, when the polluted water body is subjected to total nitrogen adsorption treatment through a number of denitrifying adsorption belt rings, the organic nitrogen and inorganic nitrogen free in the polluted water body can be concentrated in the total nitrogen adsorption area, thereby increasing the total nitrogen concentration in the total nitrogen adsorption area. The high total nitrogen concentration creates sufficient nutritional conditions for the denitrifying bacteria in the total nitrogen adsorption area, prompting the denitrifying bacteria on the denitrifying selective biofilm carrier to continuously absorb organic nitrogen and inorganic nitrogen for denitrification reaction treatment, which can enable the denitrifying bacteria to continue to grow and multiply and become the dominant bacteria species in the polluted water body. At the same time, it can effectively reduce the total nitrogen concentration in the polluted water body, and greatly improve the total nitrogen treatment effect of the denitrifying selective biofilm carrier in slightly polluted water bodies.

[0036] See also Figure 1 In order to better understand the sewage total nitrogen treatment method disclosed herein, the sewage total nitrogen treatment method is further explained below:

[0037] A method for treating total nitrogen in sewage according to one embodiment comprises the following steps:

[0038] S100, obtaining a support line and a plurality of denitrifying bacteria adsorption rings, and then coating the support line with the plurality of denitrifying bacteria adsorption rings to obtain a denitrifying bacteria selective biofilm carrier.

[0039] In this embodiment, the support wire belt and several denitrifying bacteria adsorption belt rings are wrapped together through a coating process, so that the denitrifying selective biofilm carrier has good structural stability and can adapt to the water flow impact of different polluted water bodies, thereby effectively improving the adaptability of the denitrifying bacteria selective biofilm carrier.

[0040] Furthermore, in one embodiment, the support belt is formed by twisting a plurality of shaping threads. Furthermore, the shaping threads are polyester fibers. As will be appreciated, polyester fibers possess good structural strength and are not easily deformed. This ensures that the support belt formed by twisting a plurality of shaping threads possesses good structural strength. Furthermore, the support belt can maintain good structural stability when subjected to the impact of sewage water flow and when carrying activated sludge, thereby ensuring that the denitrifying bacteria selective biofilm carrier has good structural strength.

[0041] Furthermore, in one embodiment, the total nitrogen adsorption thread includes a fiber thread and a total nitrogen adsorption powder uniformly adhered to the surface of the fiber thread by an adhesive. It is understandable that before the fiber thread is wound and twisted, the fiber thread is immersed in a suspension containing an adhesive and total nitrogen adsorption powder, and then fully stirred and dried to solidify, so that the fiber thread becomes a total nitrogen adsorption thread with a total nitrogen adsorption function, that is, each total nitrogen adsorption thread forms a total nitrogen adsorption field, and a denitrifying bacteria adsorption belt is formed by winding and twisting a number of total nitrogen adsorption threads, and then the denitrifying bacteria adsorption belt and the support belt are woven to form a number of denitrifying bacteria adsorption belt rings on the support belt, so that the denitrifying bacteria adsorption belt ring structure contains total nitrogen adsorption powder inside and outside, thereby improving the total nitrogen adsorption field to polluted water. The adsorption capacity of organic nitrogen and inorganic nitrogen can effectively enhance the adsorption capacity of the total nitrogen adsorption zone constructed by several total nitrogen adsorption fields, so that the free organic nitrogen and inorganic nitrogen in the polluted water body can be concentrated in the total nitrogen adsorption zone, thereby attracting the free denitrifying bacteria in the polluted water body to the denitrifying bacteria adsorption zone ring, and sufficient organic nitrogen and inorganic nitrogen can serve as nutritional conditions for denitrifying bacteria to adsorb and cause denitrification reactions, effectively reducing the total nitrogen concentration of the polluted water body while making denitrifying bacteria the dominant bacteria in the polluted water body, greatly improving the total nitrogen treatment effect of the denitrifying bacteria selective biofilm carrier in slightly polluted water bodies.

[0042] Furthermore, the denitrifying bacteria selective biofilm carrier includes a support wire belt and several denitrifying bacteria adsorption belt rings arranged on the surface of the support wire belt, the support wire belt is a twisted wire belt formed by a plurality of shaping wires being twisted together, and the denitrifying bacteria adsorption belt rings are inserted into the wire belt one by one during the process of the plurality of shaping wires being twisted together, that is, the denitrifying bacteria adsorption belt rings are inserted one by one while being twisted together, thereby forming the denitrifying bacteria selective biofilm carrier. It should be noted that there will be a winding gap between the plurality of shaping wires during the process of being twisted together, and the denitrifying bacteria adsorption belt ring is fixed on the wire belt by inserting the denitrifying bacteria adsorption belt ring into the winding gap and then tightening it, and several denitrifying bacteria adsorption belt rings are inserted into the wire belt in sequence according to the same steps. By winding and inserting the denitrifying bacteria adsorption belt rings one by one, the connection stability between the denitrifying bacteria adsorption belt rings and the line belt is effectively improved, which can effectively improve the structural strength of the denitrifying bacteria selective biofilm carrier. At the same time, the arrangement of several denitrifying bacteria adsorption belt rings on the line belt does not interfere with each other, so that the denitrifying bacteria selective biofilm carrier has the advantage of a high attachment area when applied to slightly polluted water bodies, thereby effectively improving the adsorption effect of the denitrifying bacteria selective biofilm carrier on the denitrifying bacteria, and effectively improving the film hanging effect of the denitrifying bacteria selective biofilm carrier, thereby effectively improving the total nitrogen treatment effect of the denitrifying bacteria selective biofilm carrier.

[0043] It should also be noted that the shaping of the two ends of the wire belt is achieved by knotting the two ends of multiple shaping wires to ensure that the twisted wire belt has a good structural compactness and ensures that the wire belt has a high structural strength.

[0044] Furthermore, the denitrifying bacteria adsorption belt ring is twisted in the middle to form two figure-eight adsorption rings, and the connection point of the two figure-eight adsorption rings is inserted into the wire belt. It should be noted that, by twisting the belt ring in the middle to form two figure-eight adsorption rings, and then inserting the connection point of the two figure-eight adsorption rings into the winding gap and tightening them during the wire belt winding process, the two figure-eight adsorption rings are fixed on the wire belt. Since the two figure-eight adsorption rings are twisted into two figure-eight adsorption rings on the same denitrifying bacteria adsorption belt ring, that is to say, the two figure-eight adsorption rings have a higher connection stability, so that the strength tension of the denitrifying bacteria selective biofilm carrier reaches more than 588N, which can withstand the impact force of water flow in different water bodies and the weight of attached sludge, and is not prone to breakage, thereby effectively improving the structural strength of the denitrifying bacteria selective biofilm carrier.

[0045] Furthermore, the two described figure-eight adsorption rings are preferentially tied with two tape knots in the middle, a tape knot partition is formed between the two described tape knots, and the tape knot partition is set in the tape. It should be noted that the denitrifying bacteria adsorption belt ring is a denitrifying bacteria adsorption belt with two tape knots tied in the middle of the denitrifying bacteria adsorption belt at both ends, thereby forming two figure-eight adsorption rings, and there is a distance between the two tape knots, which is the tape knot partition. The tape knot partition is inserted into the winding gap of multiple shaping wires and then the multiple shaping wires are tightened to fix the two figure-eight adsorption rings on the belt. Furthermore, due to the existence of the tape knot partition, the inclination angle between the two figure-eight adsorption rings is greater than 0 degrees and less than 180 degrees. That is to say, by adjusting the length of the knot separator of the wire belt, the inclination angle between the two figure-eight adsorption rings can be adjusted, so that several figure-eight adsorption rings can be arranged in a spiral shape on the wire belt, so that the denitrifying bacteria selective biofilm carrier forms a three-dimensional attachment structure, that is, while increasing the attachment area of the denitrifying bacteria selective biofilm carrier, it ensures that the denitrifying bacteria selective biofilm carrier has a high structural strength, thereby effectively improving the adsorption effect of the denitrifying bacteria selective biofilm carrier on the denitrifying bacteria, and further improving the biofilm effect of the denitrifying bacteria selective biofilm carrier, thereby effectively improving the total nitrogen treatment effect of the denitrifying bacteria selective biofilm carrier.

[0046] S200: treating the polluted water to reduce the dissolved oxygen content.

[0047] In this embodiment, since denitrifying bacteria require anaerobic or hypoxic conditions to carry out denitrification reactions, it is necessary to first reduce the dissolved oxygen content of the polluted water so that the dissolved oxygen content in the polluted water is suitable for the denitrifying bacteria to carry out the denitrification reaction, that is, to ensure that the denitrifying bacteria can adsorb organic nitrogen and inorganic nitrogen in the polluted water and promote their own continuous growth and reproduction.

[0048] It should be noted that if the dissolved oxygen content is too high, oxygen will compete with nitrate in the polluted water for electron donors, thereby inhibiting the activity of denitrifying enzymes.

[0049] S300, placing the denitrifying bacteria selective biofilm carrier in the polluted water body after the dissolved oxygen reduction treatment, and marking the position of the denitrifying bacteria selective biofilm carrier in the polluted water body as a total nitrogen adsorption area.

[0050] In this embodiment, the denitrifying bacteria selective biofilm carrier is fixed on the hanging rope bracket of the polluted water body to ensure that the denitrifying bacteria selective biofilm carrier will not be washed away by the water flow.

[0051] S400 , performing total nitrogen adsorption treatment on the polluted water body by using a plurality of the denitrifying bacteria adsorption belt rings, so that the organic nitrogen and inorganic nitrogen free in the polluted water body are concentrated in the total nitrogen adsorption area.

[0052] In this embodiment, the total nitrogen concentration of the slightly polluted water body is between 0 mg / L and 40 mg / L, which seems to be a high concentration. However, the area of the polluted water body is large, and organic nitrogen and inorganic nitrogen are dispersed in each area of the polluted water body, resulting in different total nitrogen concentrations in each area of the polluted water body. However, the placement area of the denitrifying bacteria selective biofilm carrier is fixed and limited. Therefore, the denitrifying bacteria adsorption belt ring formed by twisting a plurality of total nitrogen adsorption wires forms a total nitrogen adsorption field, which can concentrate free organic nitrogen and inorganic nitrogen in the polluted water body in the total nitrogen adsorption field. The adsorption force of the plurality of denitrifying bacteria adsorption belt rings is sufficient to increase the total nitrogen concentration of the total nitrogen adsorption area, making the total nitrogen adsorption area a local high-concentration total nitrogen enrichment area in the polluted water body, which can provide sufficient nutritional conditions for denitrifying bacteria, promote the growth and reproduction of denitrifying bacteria, and effectively reduce the total nitrogen concentration in the polluted water body.

[0053] S500 , attracting denitrifying bacteria in the polluted water body through the total nitrogen adsorption zone, so that the denitrifying bacteria adhere to a plurality of denitrifying bacteria adsorption belt rings.

[0054] In this embodiment, since the total nitrogen adsorption zone becomes a local high-concentration total nitrogen enrichment zone in the polluted water body, it can attract free denitrifying bacteria in the polluted water body and make the denitrifying bacteria attach to the denitrifying bacteria adsorption belt ring, and the total nitrogen adsorption zone provides sufficient nutritional conditions for the denitrifying bacteria, promotes the continuous growth and reproduction of the denitrifying bacteria, makes the denitrifying bacteria become the dominant bacteria group in the total nitrogen adsorption zone, increases the concentration of denitrifying bacteria in the polluted water body, and thus effectively reduces the total nitrogen concentration in the polluted water body.

[0055] It should be noted that the denitrifying bacteria selective biofilm carrier is not only attached with denitrifying bacteria, but also with other bacterial groups. It only promotes the growth and reproduction of denitrifying bacteria in the total nitrogen adsorption area, thereby increasing the concentration of denitrifying bacteria in polluted water bodies.

[0056] S600, denitrifying bacteria on the denitrifying bacteria selective biofilm carrier perform denitrification reaction on the organic nitrogen and inorganic nitrogen in the total nitrogen adsorption zone.

[0057] In this embodiment, the organic nitrogen in the total nitrogen adsorption zone can provide energy and electron donors for denitrifying bacteria, prompting the denitrifying bacteria to reduce nitrate to nitrogen gas, and can also oxidize and decompose organic nitrogen, thereby effectively reducing the total nitrogen concentration of the polluted water body.

[0058] In one embodiment, the total nitrogen adsorption powder includes activated carbon, sulfur, iron powder, and iron sulfide. It should be noted that, by mixing an adhesive, activated carbon, sulfur, iron powder, and iron sulfide to form a suspension containing the adhesive and the total nitrogen adsorption powder, and then immersing the fiber filaments in the suspension containing the adhesive and the total nitrogen adsorption powder and fully stirring, the fiber filaments form total nitrogen adsorption filaments after drying and solidification, that is, the total nitrogen adsorption powder is evenly adhered to the fiber filaments, and the activated carbon, sulfur, iron powder, and iron sulfide are evenly distributed, so that the adsorption force of each total nitrogen adsorption field of the denitrifying bacteria selective biofilm carrier is relatively consistent, thereby achieving the effect of uniform attachment of the denitrifying bacteria.

[0059] Furthermore, activated carbon, with its high surface area and rich pore structure, is capable of adsorbing not only inorganic nitrogen compounds but also organic nitrogen compounds and heavy metal ions in polluted water. The addition of activated carbon enhances the denitrifying bacteria's adsorption band's ability to absorb total nitrogen, making it an essential component of the denitrifying bacteria's adsorption band's formation of a total nitrogen adsorption field. Simultaneously, heavy metal ions can attach to organic nitrogen, which is then degraded during the denitrification reaction to form activated sludge, which is then discharged with the activated sludge. This effectively enhances the wastewater treatment effectiveness of the denitrifying bacteria's selective biofilm carrier in polluted water.

[0060] Furthermore, the addition of sulfur can provide necessary electrons for denitrifying bacteria, that is, sulfur can serve as an electron donor for denitrifying bacteria, making the denitrifying bacteria adsorption ring attractive to denitrifying bacteria, thereby improving the adsorption effect of the denitrifying bacteria adsorption ring on denitrifying bacteria, and can effectively improve the biofilm formation effect of the denitrifying bacteria selective biofilm carrier, thereby effectively improving the total nitrogen treatment effect of the denitrifying bacteria selective biofilm carrier.

[0061] Furthermore, the addition of iron powder can stimulate the activity of denitrifying bacteria. Specifically, iron powder can serve as an electron donor for denitrifying bacteria, which can further enhance the attraction of the denitrifying bacteria adsorption ring to denitrifying bacteria. At the same time, in polluted water bodies with low dissolved oxygen content, iron powder hardly reacts with water, ensuring the stability of the total nitrogen adsorption powder layer, further improving the adsorption effect of the denitrifying bacteria adsorption ring on denitrifying bacteria, further improving the biofilm formation effect of the denitrifying bacteria selective biofilm carrier, and further improving the total nitrogen treatment effect of the denitrifying bacteria selective biofilm carrier.

[0062] Furthermore, the addition of iron sulfide can also stimulate the activity of denitrifying bacteria. Iron sulfide can serve as an electron donor for denitrifying bacteria. Specifically, the sulfur and iron elements in iron sulfide can release electrons through redox reactions. These electrons can attract denitrifying bacteria to attach to the denitrifying bacteria adsorption ring. Denitrifying bacteria use these electrons to promote the reduction of nitrate into nitrogen gas. In other words, the addition of iron sulfide can enhance the attraction of the denitrifying bacteria adsorption ring to denitrifying bacteria, further improve the adsorption effect of the denitrifying bacteria adsorption ring on denitrifying bacteria, further improve the biofilm formation effect of the denitrifying bacteria selective biofilm carrier, and further improve the total nitrogen treatment effect of the denitrifying bacteria selective biofilm carrier.

[0063] It can be seen that by combining activated carbon, sulfur, iron powder and iron sulfide on the denitrifying bacteria adsorption ring at the same time, not only can the adsorption capacity of the denitrifying bacteria adsorption ring for organic nitrogen, inorganic nitrogen and heavy metal ions in polluted water be enhanced, but also the adsorption capacity for free denitrifying bacteria in polluted water can be enhanced. The adsorption capacity of the two is enhanced, so that the total nitrogen adsorption area is turned into a local high-concentration total nitrogen enrichment area in the polluted water, and the total nitrogen adsorption area is also turned into a local high-concentration denitrifying bacteria enrichment area in the polluted water. That is to say, through the synergistic effect of the four powders, not only a suitable growth environment is created for denitrifying bacteria, but also the free denitrifying bacteria in the polluted water can be concentrated in the total nitrogen adsorption area, which can effectively reduce the total nitrogen concentration in the polluted water and maximize the total nitrogen treatment effect of the denitrifying bacteria selective biofilm carrier in the polluted water.

[0064] In one embodiment, the mass ratio of the activated carbon, the sulfur, the iron powder, and the iron sulfide powder is (10-20):(5-8):(0.5-2):(5-8). It is understood that at this mass ratio, the denitrifying bacteria adsorption ring has a good total nitrogen adsorption capacity and a good denitrifying bacteria adsorption capacity, so that the organic nitrogen, inorganic nitrogen, and denitrifying bacteria free in the polluted water are concentrated in the total nitrogen adsorption zone, thereby effectively reducing the total nitrogen concentration in the polluted water.

[0065] In one embodiment, the mass of the total nitrogen adsorption powder accounts for 3% to 5% of the total mass of the denitrifying bacteria selective biofilm carrier. It is understandable that the mass of the total nitrogen adsorption powder accounts for 3% to 5% of the total mass of the denitrifying bacteria selective biofilm carrier, so that the total nitrogen adsorption powder can cover each fiber thread, ensuring that each denitrifying bacteria adsorption belt ring can form a total nitrogen adsorption field, and at the same time can enhance the adsorption force of the denitrifying bacteria adsorption belt ring on the denitrifying bacteria, so that the total nitrogen adsorption area becomes a local high-concentration total nitrogen enrichment area and a local high-concentration denitrifying bacteria enrichment area, so that the total nitrogen concentration in the polluted water body can be effectively reduced. In addition, the free heavy metal ions in the polluted water body will also be adsorbed on the denitrifying bacteria adsorption belt ring and attached to the organic nitrogen after degradation to form activated sludge. Then, by discharging the activated sludge, the concentration of heavy metal ions in the polluted water body can be effectively reduced, and the sewage treatment effect of the denitrifying bacteria selective biofilm carrier can be maximized.

[0066] In one embodiment, the adhesive is a combination of one or more of chitosan adhesive, gelatin, polylactic acid adhesive, polyurethane adhesive, and acrylate adhesive. It is understood that these adhesives can evenly adhere the total nitrogen adsorption powder to the fiber filaments, providing strong adhesion and water resistance. This allows the total nitrogen adsorption powder layer to remain stable in water and not separate from the fiber filaments, ensuring the stable formation of a total nitrogen adsorption field. This ensures that the denitrifying bacteria selective biofilm carrier has a good biofilm formation effect, resulting in a good total nitrogen treatment effect in slightly polluted water bodies.

[0067] In one embodiment, the fiber filaments are a combination of one or more of nylon fiber filaments, polypropylene fiber filaments, carbon fiber filaments, and aramid fiber filaments. It is understood that the aforementioned fiber filaments all have high structural strength, good wear resistance, and good tensile strength, thereby enhancing the structural strength of the denitrifying bacteria attachment belt ring, achieving a strength and tension of over 588N. This allows the belt ring to withstand the impact of water flow from different water bodies and the weight of attached sludge without breaking, further enhancing the structural strength of the denitrifying bacteria selective biofilm carrier.

[0068] In one embodiment, the specific steps of treating the polluted water body to reduce the dissolved oxygen content are:

[0069] The water inflow of the polluted water body is increased, and the polluted water body is stirred by a stirring system.

[0070] It should be noted that by increasing the water inflow of the polluted water body, diluting the dissolved oxygen content in the polluted water body, and then stirring the polluted water body through the stirring system, while stopping the input of the aeration system, the dissolved oxygen content in the polluted water body is consumed, so that the dissolved oxygen concentration is reduced to a concentration suitable for the growth of denitrifying bacteria.

[0071] In one embodiment, the dissolved oxygen content of the polluted water after the dissolved oxygen reduction treatment is 0 mg / L to 0.2 mg / L. It is understood that controlling the dissolved oxygen content of the polluted water below 0.2 mg / L is the optimal reaction condition for denitrifying bacteria. This can prevent the polluted water from competing with nitrate for electron donors, thereby effectively increasing the activity of denitrifying enzymes, prompting denitrifying bacteria to continuously adsorb organic nitrogen and inorganic nitrogen in the total nitrogen adsorption zone and undergo denitrification reactions, thereby effectively increasing the concentration of denitrifying bacteria in the polluted water and further reducing the total nitrogen concentration of the polluted water.

[0072] In one embodiment, before the step of reducing the dissolved oxygen content of the polluted water, the method for treating total nitrogen in sewage further comprises the following steps:

[0073] The polluted water body is subjected to nitrification treatment through a nitrification system.

[0074] It is understandable that polluted water bodies need to be nitrified by a nitrification system before denitrification treatment to convert the ammonia nitrogen in the polluted water bodies into nitrates.

[0075] The present disclosure also provides a denitrification selective biofilm carrier, which is used in the method for treating total nitrogen in sewage as described in any of the above embodiments;

[0076] The above-mentioned method for treating total nitrogen in wastewater includes the following steps: obtaining a support line and a plurality of denitrifying bacteria adsorption belt loops, and then wrapping the support line with the plurality of denitrifying bacteria adsorption belt loops to form a denitrifying bacteria selective biofilm carrier. The polluted water is then treated to reduce the dissolved oxygen level. The denitrifying bacteria selective biofilm carrier is placed in the polluted water after the treatment, with the position of the denitrifying bacteria selective biofilm carrier within the polluted water marked as a total nitrogen adsorption zone. The polluted water is subjected to total nitrogen adsorption treatment using the plurality of denitrifying bacteria adsorption belt loops, concentrating the free organic and inorganic nitrogen in the polluted water within the total nitrogen adsorption zone. The total nitrogen adsorption zone attracts denitrifying bacteria in the polluted water, causing them to attach to the plurality of denitrifying bacteria adsorption belt loops. The denitrifying bacteria on the denitrifying bacteria selective biofilm carrier then undergo a denitrification reaction on the organic and inorganic nitrogen within the total nitrogen adsorption zone. The denitrification adsorption belt ring is formed by twisting a plurality of total nitrogen adsorption wires.

[0077] In this embodiment, since the denitrifying bacteria adsorption belt ring is formed by winding and twisting a plurality of total nitrogen adsorption wires, the denitrifying bacteria adsorption belt ring forms a total nitrogen adsorption field, and a plurality of denitrifying bacteria adsorption belt rings are coated on the support belt to obtain a denitrifying bacteria selective biofilm carrier, so that the denitrifying bacteria selective biofilm carrier forms a total nitrogen adsorption area with a relatively large adsorption strength. In this way, when the polluted water body is subjected to total nitrogen adsorption treatment through a plurality of denitrifying adsorption belt rings, the organic nitrogen and inorganic nitrogen free in the polluted water body can be concentrated in the total nitrogen adsorption area, thereby improving the total nitrogen concentration in the total nitrogen adsorption area. Denitrifying bacteria free in the polluted water body are attracted to the total nitrogen adsorption zone and attached to several denitrifying bacteria adsorption rings. The high total nitrogen concentration creates sufficient nutritional conditions for the denitrifying bacteria in the total nitrogen adsorption zone, prompting the denitrifying bacteria on the denitrification selective biofilm carrier to continuously absorb organic nitrogen and inorganic nitrogen for denitrification reaction treatment, which can enable the denitrifying bacteria to continue to grow and multiply and become the dominant bacteria species in the polluted water body. At the same time, it can effectively reduce the total nitrogen concentration in the polluted water body, and greatly improve the total nitrogen treatment effect of the denitrification selective biofilm carrier in slightly polluted water bodies.

[0078] Examples are listed below, but it should be noted that the following implementation cases do not exhaust all possible situations, and the materials used in the following examples can be obtained from commercial channels unless otherwise specified.

[0079] Implementation Case 1

[0080] Experimental process 1: Biofilm carrier formation

[0081] A glass reactor 550 mm long, 600 mm high, and 200 mm wide was made (with a stirrer in the middle). Municipal sewage was added to the reactor, and biofilm carriers were fixed to the reactor in two rows, 4 in each row, for a total of 8. Municipal sewage plant sludge was added at a sludge dosage of 3000 mg / L. Aerobic biofilm formation was carried out for 15 days with continuous water inflow, and biofilm formation was completed. Among them, a total of four groups of experiments were set up: the reaction group: the denitrification-selective biofilm carrier was added; the control group 1: the braided biofilm carrier was added; the control group 2: the brush biofilm carrier was added; and the control group 3: no biofilm carrier was added, but 3000 mg / L activated sludge was added.

[0082] Test process 2:

[0083] After biofilm formation was complete, the reactor was emptied of sludge and wastewater, and water from a polluted river in Guangdong province, treated with preliminary nitrification, was continuously fed to the reactor again. An appropriate amount of glucose was added to the water. The TN index of the reactor's inlet and outlet water was measured. Four sets of experiments were conducted simultaneously, and the test results are shown in Table 1.

[0084] Table 1

[0085]

[0086] Implementation Case 2

[0087] Experimental process 1: Biofilm carrier formation

[0088] A glass reactor 550 mm long, 600 mm high, and 200 mm wide was made (with a stirrer in the middle). Municipal sewage was added to the reactor, and biofilm carriers were fixed to the reactor in two rows, 4 in each row, for a total of 8. Municipal sewage plant sludge was added at a sludge dosage of 3000 mg / L. Aerobic biofilm formation was carried out for 15 days with continuous water inflow, and biofilm formation was completed. Among them, a total of four groups of experiments were set up: the reaction group: the denitrification-selective biofilm carrier was added; the control group 1: the braided biofilm carrier was added; the control group 2: the brush biofilm carrier was added; and the control group 3: no biofilm carrier was added, but 3000 mg / L activated sludge was added.

[0089] Test process 2:

[0090] After biofilm formation was complete, the reactor was emptied of sludge and wastewater, and water from a snakehead fish aquaculture pond in Guangdong province was continuously fed again, with an appropriate amount of glucose added. The TN index of the reactor's inlet and outlet water was measured. Four sets of experiments were conducted simultaneously, and the test results are shown in Table 2.

[0091] Table 2

[0092]

[0093] Implementation Case 3

[0094] Experimental process 1: Biofilm carrier formation

[0095] A glass reactor 550 mm long, 600 mm high, and 200 mm wide was made (with a stirrer in the middle). Municipal sewage was added to the reactor, and biofilm carriers were fixed to the reactor in two rows, 4 in each row, for a total of 8. Municipal sewage plant sludge was added at a sludge dosage of 3000 mg / L. Aerobic biofilm formation was carried out for 15 days with continuous water inflow, and biofilm formation was completed. Among them, a total of four groups of experiments were set up: the reaction group: the denitrification-selective biofilm carrier was added; the control group 1: the braided biofilm carrier was added; the control group 2: the brush biofilm carrier was added; and the control group 3: no biofilm carrier was added, but 3000 mg / L activated sludge was added.

[0096] Test process 2:

[0097] After biofilm formation was complete, the reactor was emptied of sludge and wastewater, and the tailwater from a wastewater treatment plant in Guangdong Province was continuously fed again, with an appropriate amount of glucose added. The TN index of the reactor's inlet and outlet water was measured. Four sets of experiments were conducted simultaneously, and the test results are shown in Table 3.

[0098] Table 3

[0099]

[0100] Implementation Case 4

[0101] Experimental process 1: Biofilm carrier formation

[0102] A glass reactor 550 mm long, 600 mm high, and 200 mm wide was made (with a stirrer in the middle). Municipal sewage was added to the reactor, and biofilm carriers were fixed to the reactor in two rows, 4 in each row, for a total of 8. Municipal sewage plant sludge was added at a sludge dosage of 3000 mg / L. Aerobic biofilm formation was carried out for 15 days with continuous water inflow, and biofilm formation was completed. Among them, a total of four groups of experiments were set up: the reaction group: the denitrification-selective biofilm carrier was added; the control group 1: the braided biofilm carrier was added; the control group 2: the brush biofilm carrier was added; and the control group 3: no biofilm carrier was added, but 3000 mg / L activated sludge was added.

[0103] Test process 2:

[0104] After biofilm formation was complete, the reactor was emptied of sludge and wastewater, and water from a Guangdong reservoir, treated with preliminary nitrification, was continuously fed back into the reactor. An appropriate amount of glucose was added to the water. The TN index of the reactor's inlet and outlet water was measured. Four sets of tests were conducted simultaneously, and the test results are shown in Table 5.

[0105] Table 5

[0106]

[0107] Implementation Case 5

[0108] Experimental process 1: Biofilm carrier formation

[0109] A glass reactor 550 mm long, 600 mm high, and 200 mm wide was made (with a stirrer in the middle). Municipal sewage was added to the reactor, and biofilm carriers were fixed to the reactor in two rows, 4 in each row, for a total of 8. Municipal sewage plant sludge was added at a sludge dosage of 3000 mg / L. Aerobic biofilm formation was carried out for 15 days with continuous water inflow, and biofilm formation was completed. Among them, a total of four groups of experiments were set up: the reaction group: the denitrification-selective biofilm carrier was added; the control group 1: the braided biofilm carrier was added; the control group 2: the brush biofilm carrier was added; and the control group 3: no biofilm carrier was added, but 3000 mg / L activated sludge was added.

[0110] Test process 2:

[0111] After biofilm formation was complete, the reactor was emptied of sludge and wastewater, and water from a bullfrog breeding pond in Guangdong province, treated with preliminary nitrification, was continuously fed again. An appropriate amount of glucose was added to the water. The TN index of the reactor's inlet and outlet water was measured. Four sets of experiments were conducted simultaneously, and the test results are shown in Table 5.

[0112] Table 5

[0113]

[0114] From Tables 1 to 5, the denitrification selective biofilm carrier disclosed in the present invention has a higher treatment efficiency for total nitrogen in polluted water than the braided biofilm carrier and the brush biofilm carrier, and the treatment efficiency is also higher than the conventional activated sludge treatment method, which can reflect that the denitrification selective biofilm carrier disclosed in the present invention has a better removal limit for total nitrogen than the braided biofilm carrier, the brush biofilm carrier and the activated sludge method. In other words, the sewage total nitrogen treatment method disclosed in the present invention can reduce the total nitrogen in the effluent to a lower level.

[0115] As can be seen from Table 5, even when the total nitrogen in the influent is about 5 mg / L, the total nitrogen removal rate can still reach 75.00% by adopting the denitrification selective biofilm carrier disclosed in the present invention, which is much higher than the braided biofilm carrier, brush biofilm carrier and activated sludge treatment method. This also shows that the sewage total nitrogen treatment method disclosed in the present invention has obvious advantages in the total nitrogen treatment efficiency when applied to different slightly polluted water bodies.

[0116] Combined with Table 1-Table 5 and Figure 2 、 Figure 3 It can be seen that Figure 2The denitrifying bacteria attachment belt rings of the denitrifying bacteria selective biofilm carrier disclosed in the present invention are arranged on the support belt without interfering with each other. At the same time, the denitrifying bacteria attachment belt rings are formed by twisting a plurality of total nitrogen adsorption wires, so that each denitrifying bacteria attachment belt ring can form a total nitrogen adsorption field and a denitrifying bacteria adsorption field in the sewage. That is to say, while increasing the attachment space of the denitrifying selective biofilm carrier, a local high-concentration total nitrogen enrichment area and a denitrifying bacteria enrichment area are formed at the same time, so that the concentration of denitrifying bacteria in the polluted water body is significantly improved, and the total nitrogen concentration in the polluted water body can be effectively reduced. Figure 3 It is a conventional braided biofilm carrier. The braided ropes of the braided biofilm carrier are arranged relatively densely on the rope core, which will interfere with each other, resulting in a reduction in the attachment space of denitrifying bacteria. At the same time, it does not have the total nitrogen adsorption function and the denitrifying bacteria adsorption function. This also causes the total nitrogen treatment effect of the braided biofilm carrier in slightly polluted water bodies to be significantly weaker than the denitrifying bacteria selective biofilm carrier disclosed in the present invention.

[0117] Compared with the prior art, the present disclosure has at least the following advantages:

[0118] Since the denitrifying bacteria adsorption belt ring is formed by winding and twisting a number of total nitrogen adsorption wires, the denitrifying bacteria adsorption belt ring forms a total nitrogen adsorption field, and a number of denitrifying bacteria adsorption belt rings are coated on the support belt to obtain a denitrifying bacteria selective biofilm carrier, so that the denitrifying bacteria selective biofilm carrier forms a total nitrogen adsorption area with a larger adsorption intensity. In this way, when the polluted water body is subjected to total nitrogen adsorption treatment through a number of denitrifying adsorption belt rings, the organic nitrogen and inorganic nitrogen free in the polluted water body can be concentrated in the total nitrogen adsorption area, thereby increasing the total nitrogen concentration in the total nitrogen adsorption area. The denitrifying bacteria in the polluted water body are attracted to the total nitrogen adsorption zone and attached to several denitrifying bacteria adsorption rings. The high total nitrogen concentration creates sufficient nutritional conditions for the denitrifying bacteria in the total nitrogen adsorption zone, prompting the denitrifying bacteria on the denitrification selective biofilm carrier to continuously absorb organic nitrogen and inorganic nitrogen for denitrification reaction treatment, which can enable the denitrifying bacteria to continue to grow and multiply and become the dominant bacteria species in the polluted water body. At the same time, it can effectively reduce the total nitrogen concentration in the polluted water body, and greatly improve the total nitrogen treatment effect of the denitrification selective biofilm carrier in slightly polluted water bodies.

[0119] The above-described embodiments merely represent several implementation methods of the present disclosure. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the disclosed patent. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the scope of the present disclosure, all of which fall within the scope of protection of the present disclosure. Therefore, the scope of protection of the disclosed patent shall be determined by the appended claims.

Claims

1. A method for treating total nitrogen in sewage, characterized in that: The steps include: Obtaining a support line and a plurality of denitrifying bacteria adsorption rings, and then coating the support line with the plurality of denitrifying bacteria adsorption rings to obtain a denitrifying bacteria selective biofilm carrier; The contaminated water body is stirred by a stirring system to reduce the dissolved oxygen content of the contaminated water body, wherein the dissolved oxygen content of the contaminated water body after the dissolved oxygen reduction treatment is 0 mg / L to 0.2 mg / L; placing the denitrifying bacteria selective biofilm carrier in the polluted water body after the dissolved oxygen reduction treatment, and marking the position of the denitrifying bacteria selective biofilm carrier in the polluted water body as a total nitrogen adsorption zone; The polluted water body is subjected to total nitrogen adsorption treatment by a plurality of denitrifying bacteria adsorption belt rings, so that the organic nitrogen and inorganic nitrogen free in the polluted water body are concentrated in the total nitrogen adsorption zone; Attracting denitrifying bacteria in the polluted water body through the total nitrogen adsorption zone, so that the denitrifying bacteria adhere to a plurality of the denitrifying bacteria adsorption belt rings; The denitrifying bacteria on the denitrifying bacteria selective biofilm carrier perform denitrification reaction on the organic nitrogen and inorganic nitrogen in the total nitrogen adsorption area; The denitrifying bacteria adsorption belt ring is formed by twisting a plurality of total nitrogen adsorption wires; the support wire belt is a twisted wire belt formed by twisting a plurality of shaping wires together; The shaping thread is polyester fiber; The total nitrogen adsorption thread comprises a fiber thread and a total nitrogen adsorption powder uniformly adhered to the surface of the fiber thread by an adhesive; wherein, before winding and twisting the fiber thread, the fiber thread is immersed in a suspension containing the adhesive and the total nitrogen adsorption powder, fully stirred and dried to solidify, so that the fiber thread becomes a total nitrogen adsorption thread with a total nitrogen adsorption function; the fiber thread is a combination of one or more of nylon fiber threads, polypropylene fiber threads, carbon fiber threads and aramid fiber threads; The specific operation steps of wrapping a plurality of denitrifying bacteria adsorption belt rings on the support belt are as follows: The denitrifying bacteria adsorption belt rings are inserted into the belt one by one during the process of twisting the plurality of shaping wires, that is, the denitrifying bacteria adsorption belt rings are inserted one by one while twisting, thereby forming the denitrifying bacteria selective biofilm carrier; The denitrifying bacteria adsorption belt ring is twisted in the middle to form two figure-eight adsorption rings, and the connection between the two figure-eight adsorption rings is inserted into the line belt; Two string knots are preferably tied between the two figure-eight adsorption rings, a string knot partition is formed between the two string knots, and the string knot partition is arranged in the string; The inclination angle between the two figure-eight adsorption rings is greater than 0 degrees and less than 180 degrees; The total nitrogen adsorption powder includes activated carbon, sulfur, iron powder and iron sulfide; The mass ratio of the activated carbon, the sulfur, the iron powder and the iron sulfide powder is (10-20): (5-8): (0.5-2): (5-8); The mass of the total nitrogen adsorption powder accounts for 3% to 5% of the total mass of the denitrifying bacteria selective biofilm carrier; The adhesive is one or more combinations of chitosan adhesive, gelatin, polylactic acid adhesive, polyurethane adhesive and acrylate adhesive.

2. The method for treating total nitrogen in sewage according to claim 1, wherein Before the operation step of reducing the dissolved oxygen content of the polluted water, the following steps are also included: The water inflow of the polluted water body is increased, and the polluted water body is stirred by a stirring system.

3. A denitrification selective biofilm carrier, characterized in that: Used to implement the method for treating total nitrogen in sewage according to any one of claims 1-2.

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