Spiral modified MBBR filler as well as preparation method and application thereof

Abstract

The invention discloses a spiral modified MBBR filler as well as a preparation method and application thereof, and belongs to the technical field of sewage treatment. The filler takes high-density polyethylene (HDPE) as a matrix and comprises the following raw materials in parts by weight: 100-105 parts of HDPE, 7-9 parts of modified hydrotalcite, 4-6 parts of an auxiliary agent, 0.7-0.9 part of an initiator, 1-2 parts of polyvinyl alcohol, 1-2 parts of chitin, 1.5-3 parts of gelatin, 5-10 parts of activated carbon, 0.5-1 part of zinc stearate and 0.3-0.5 part of an EBS dispersing agent. By optimizing the material formula and the structural design, the filler is endowed with a three-dimensional spiral porous structure, the surface roughness and the biocompatibility of the filler are effectively enhanced, and the initial attachment of microorganisms and the formation of a biological membrane are remarkably promoted. Meanwhile, due to introduction of the composite additive, ultraviolet aging is effectively delayed, the service life of the filler is prolonged, it is guaranteed that the filler still keeps excellent degradation performance in a complex sewage environment, and the filler is suitable for efficient treatment of complex water quality.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sewage treatment, in particular to a spiral modified MBBR filler, a preparation method and application thereof. BACKGROUND

[0002] The moving bed biofilm reactor (MBBR) is a high-efficiency sewage treatment technology, the core of which is to add suspended carriers (i.e. MBBR fillers) to the reactor, to significantly improve the pollutant degradation efficiency by enhancing the biomass and biodiversity in the system. In this process, microorganisms mainly grow in the form of biofilm attached to the surface of the filler, not only avoiding the restriction of hydraulic retention time on biological phase, but also providing a stable living environment for long sludge age microorganisms (such as nitrifying bacteria), thereby strengthening the simultaneous removal capacity of the reactor for various pollutants. Therefore, the MBBR process is superior to the traditional activated sludge process in terms of treatment efficiency and operation stability.

[0003] As a key component of the process, the MBBR filler is usually made of polyolefin materials (such as polyethylene, polypropylene) or polyurethane as the matrix, and is formed by extrusion or injection molding. Among them, the high-density polyethylene (HDPE) based filler is widely used in practical engineering due to its high mechanical strength, low cost, easy mass production, excellent fluidization performance, and high mass transfer efficiency. However, HDPE itself is a hydrophobic material with low surface energy and poor biological affinity, which leads to slow initial adhesion of microorganisms on its surface and insufficient biofilm formation capacity, i.e. the problems of slow biofilm formation start-up and low final biomass. In addition, HDPE fillers are prone to aging under long-term ultraviolet exposure, which reduces their mechanical properties and functional stability, and further affects their long-term use effect and pollutant degradation performance.

[0004] Traditional HDPE fillers are mostly designed as simple cylindrical or ring-shaped structures, which are easy to manufacture, but have obvious limitations in hydrodynamics. The internal water flow channel of this structure is single in form, and the specific surface area utilization rate is not high, which is easy to form directional flow or short flow in the reactor, resulting in uneven distribution of fluid shear force and low mixing efficiency. The fillers in the fluidized state mostly move in a regular translation, which is difficult to promote interphase mixing and mass transfer in the reactor, and some areas may even have accumulation or dead angles, affecting the biofilm renewal and substrate-biofilm contact efficiency. At the same time, due to the single interaction mode of the filler and the water flow, the oxygen mass transfer efficiency and energy utilization rate are low, and in actual operation, it is often necessary to rely on increasing the aeration intensity to achieve complete fluidization, causing the increase of energy consumption.

[0005] To improve the performance of fillers, some studies have tried to introduce functional additives, such as Fe3O4, to enhance the degradation ability of pollutants by utilizing its magnetic and catalytic properties. However, as an inorganic particle, Fe3O4 has a significant density difference and poor compatibility with the HDPE matrix, which can easily be peeled off from the surface due to the collision and friction between fillers in actual operation, resulting in the loss of active ingredients and uneven fluidization. More notably, under complex water quality conditions such as high chloride ions or high sulfate, Fe3O4 is prone to ion erosion and dissolution, leading to rapid decay of its activity, which severely restricts the application potential of this type of modified filler in complex industrial wastewater.

[0006] Therefore, developing a modification strategy that can simultaneously improve the hydrophilicity, UV aging resistance, and pollutant degradation activity of MBBR fillers, while also having excellent hydraulic characteristics, has become an important direction for improving the performance of MBBR processes. By optimizing the material formula and designing a three-dimensional spiral porous structure, the specific surface area of the filler can be effectively increased, the surface roughness can be enhanced, and more abundant ecological niches can be provided for microbial attachment. At the same time, the formation of turbulent flow and gas-liquid-solid three-phase mixing can be promoted, and the fluidization energy consumption can be reduced. This functional component synergistic strategy and structural modification strategy is expected to achieve efficient, stable, and low-energy consumption wastewater biological treatment applications. SUMMARY

[0007] To solve the above technical problems, the present application provides a spiral modified MBBR filler and its preparation method and application.

[0008] The object of the present application can be achieved by the following technical solutions: A spiral modified MBBR filler, comprising the following raw materials by weight: HDPE 100-105 parts, modified hydrotalcite 7-9 parts, auxiliary agent 4-6 parts, initiator 0.7-0.9 parts, polyvinyl alcohol 1-2 parts, chitin 1-2 parts, gelatin 1.5-3 parts, activated carbon 5-10 parts, zinc stearate 0.5-1 parts, EBS dispersant 0.3-0.5 parts; Further, the initiator is dicumyl peroxide; The preparation of the spiral modified MBBR filler comprises the following steps: HDPE and auxiliary agent are heated and melted and mixed, then the initiator is added, and after the temperature is raised for melting reaction, the temperature is lowered, the modified hydrotalcite, polyvinyl alcohol, chitin, gelatin, activated carbon, zinc stearate, and EBS dispersant are mixed and then heated and melted and blended, extruded and granulated, and extruded and formed into a cylindrical blank by a screw; then the cylindrical blank is sheared by a hard alloy spiral knife, immersed in water after shearing is completed, dried after being taken out, and treated by plasma to obtain a spiral modified MBBR filler; The preparation of the spiral modified MBBR filler comprises the following specific steps: HDPE, additives are melt-mixed at 175-180°C, then the initiator is added, heated to 185-190°C, melt reaction for 13-17 min, cooled to 80-90°C, modified hydrotalcite, polyvinyl alcohol, chitin, gelatin, activated carbon, zinc stearate, EBS dispersant are mixed at 800-1000 rpm for 10-15 min, then heated and melt blended at 190-200°C, 300-400 rpm, extruded and granulated, and formed into cylindrical blanks by screw extruder at 180-210°C; then the cylindrical blanks are sheared by a hard alloy spiral knife, and after shearing, immersed in water at 75-80°C for 1.8-2h, then dried at 60-65°C for 4-4.5h, and then treated by plasma to obtain spiral modified MBBR filler; Further, the diameter of the cylindrical blank is 10-25mm, and the length-diameter ratio is 0.8-1.2; the blade helix angle of the hard alloy spiral knife is 30-60°, the blade width is 2-4mm, and the blade depth is 1.5-3mm; during the shearing process of the hard alloy spiral knife, the linear velocity is 0.5-1.5m / s, and the feed is 0.2-0.5mm / r; the plasma treatment conditions are power 300-500W, and time 90-120s; Further, the spiral modified MBBR filler is used for sewage treatment; The modified hydrotalcite is prepared by the following steps: Step G1, add thiophene aldehyde to acetic anhydride, stir, then add potassium salt, heat and reflux to stir to obtain product g1; add product g1 to DMF, stir, add dichlorosulfoxide, heat and reflux to stir to obtain product g2; mix nitroimidazole and DMSO, stir, then drop the mixed solution of product g2 in an ice water bath, heat and stir after dropping to obtain product g3; Step G2, mix product g3, DMAC, and ethanol solution, stir, add sodium dithionite, stir to obtain product g4; mix product g4, epichlorohydrin, and DMF, stir, then add tetra-n-butylammonium chloride, heat and stir, then add alkali solution, continue to stir to obtain product g5; Step G3, add aldehyde pyrimidine to acetic anhydride, stir, then add anhydrous potassium carbonate, heat and reflux to stir to obtain product g6; mix product g6, DMAC, and triethylamine, stir, then add product g5, heat and stir, then heat and stir again to obtain product g7; Step G4, mix sodium carboxybenzenesulfonate, DMSO, and ethanol, stir, then add chlorosulfoxide, heat and reflux to stir to obtain product g8; mix product g7, ethyl acetate, and DMAC, stir, then add the mixed solution of product g8 in an ice water bath, heat and reflux to stir to obtain product g9; mix product g9, DMF, and ethanol in a protective gas atmosphere, stir after reflux, then add aqueous acetic acid and zinc particles, reflux and stir to obtain product g10; Step G5: Add zinc chloride and aluminum chloride hexahydrate to deionized water, stir and adjust the pH, heat and stir, then age, wash and dry to obtain zinc aluminum hydrotalcite; add zinc aluminum hydrotalcite and product g10 to solvent 1, ultrasonically disperse, stir and adjust the pH, heat and stir, wash until neutral and dry to obtain modified hydrotalcite. The preparation of the modified hydrotalcite includes the following specific steps: Step G1: Add thiophene aldehyde to acetic anhydride, stir for 5-10 min, add potassium salt and turn on reflux, heat to 95-105℃, stir for 2.5-3 h to obtain product g1; add product g1 to DMF, stir and add thionyl chloride, heat to 55-60℃, reflux and stir for 4-4.5 h to obtain product g2; mix nitroimidazole and DMSO, stir for 20-25 min, add the mixture of product g2 dropwise in an ice-water bath, heat to 50-55℃ after the addition is complete, stir and react for 7.5-8 h to obtain product g3; Further, the ratio of thiophene aldehyde, acetic anhydride, and potassium salt is 5.8-6.2g: 5-5.4g: 1.4-2.0g; the thiophene aldehyde is 3-thiophenecaraldehyde; the potassium salt is anhydrous potassium carbonate; the ratio of product g1, DMF, and thionyl chloride is 6.5-7g: 30-35mL: 6-6.5g; the ratio of the mixture of nitroimidazole, DMSO, and product g2 is 5.9-6.3g: 13-15mL: 25-30mL; the nitroimidazole is 4-nitroimidazole; the mixture of product g2 is obtained by mixing product g2 and DMSO at a ratio of 7.5-8g: 15-20mL. In step G1, the aldehyde group of thiophene aldehyde reacts with acetic anhydride to give thiophene containing an alkenoic acid; the carboxyl group of product g1 reacts with thionyl chloride to give product g2 containing an acyl chloride; the acyl chloride of product g2 reacts with the secondary amine of product g2 to give product g3. Step G2: Mix product g3, DMAC, and ethanol solution, stir for 30-35 min, add sodium dithionite, and stir the reaction at pH 8-8.5 and 45-50℃ for 2.8-3.2 h to obtain product g4; mix product g4, epichlorohydrin, and DMF, stir for 30-40 min, add tetra-n-butylammonium chloride, and stir the reaction at 95-100℃ for 2-3 h, then add alkaline solution and continue stirring for 1.5-2 h to obtain product g5; Further, the ratio of the amounts of product g3, DMAC, ethanol solution, sodium hydrosulfite is 13.5-14.5 g: 28-32 mL: 25-30 mL: 8.5-9 g; the ethanol solution is obtained by mixing ethanol with a volume fraction of 95% and water according to a volume ratio of 2-2.5: 1-1.5; the ratio of the amounts of product g4, epichlorohydrin, DMF, tetra-n-butylammonium chloride, alkali solution is 12-12.5 g: 9.6-10.0 g: 45-55 mL: 40-50 mg: 20-24 mL; the alkali solution is a potassium hydroxide or sodium hydroxide solution with a mass fraction of 40-45%; In the reaction process of step G2, the nitro group of product g3 is reduced to an amino group to obtain product g4; the amino group of product g4 is first ring-opened and then ring-closed with epichlorohydrin to obtain product g5 with an epoxy group; In step G3, the aldehyde pyrimidine is added to acetic anhydride, stirred for 20-25 min, then anhydrous potassium carbonate is added to start reflux, heated to 90-100°C, and stirred for 3.5-4 h to obtain product g6; product g6, DMAC, and triethylamine are mixed, stirred for 35-40 min, then product g5 is added, heated to 75-85°C, and stirred for 7.5-8 h, then heated to 105-110°C and continuously stirred for 1.5-1.7 h to obtain product g7; Further, the ratio of the amounts of aldehyde pyrimidine, acetic anhydride, and anhydrous potassium carbonate is 7.0-7.5 g: 5.5-6 g: 1.8-2.2 g; the aldehyde pyrimidine is 2-methoxy-5-aldehyde pyrimidine; the ratio of the amounts of product g6, DMAC, triethylamine, and product g5 is 7.8-8.2 g: 65-70 mL: 0.2-0.3 g: 22.5-23 g; In the reaction process of step G3, the aldehyde group of the aldehyde pyrimidine reacts with acetic anhydride to obtain a pyrimidine containing an alkenoic acid, i.e., product g6; the carboxyl group of product g6 reacts with the epoxy group of product g5 to obtain product g7 containing a secondary alcohol hydroxyl group; In step G4, carboxyl sodium phenyl sulfonate, DMSO, and ethanol are mixed, stirred at 35-40°C for 30-40 min, then thionyl chloride is added, and reflux stirring is performed at 60-65°C for 2.5-3 h to obtain product g8; product g7, ethyl acetate, and DMAC are mixed, stirred for 40-45 min, then the mixed solution of product g8 is added in an ice water bath, and then heated to 70-80°C, and reflux stirring is performed for 10-10.5 h to obtain product g9; in a protective gas atmosphere, product g9, DMF, and ethanol are mixed, stirred for 30-35 min, then aqueous acetic acid and zinc granules are added, and reflux stirring is performed at 85-90°C for 2-2.5 h to obtain product g10; Further, the amount ratio of sodium carboxybenzenesulfonate, DMSO, ethanol, and thionyl chloride is 11.5-12 g: 25-30 mL: 15-20 mL: 7.5-8 g; the sodium carboxybenzenesulfonate is sodium 3-carboxybenzenesulfonate; the volume fraction of ethanol is 95%; the amount ratio of product g7, ethyl acetate, DMAC, and product g8 is 30-31 g: 20-25 mL: 40-45 mL: 45-50 mL; the product g8 mixture is obtained by mixing product g8 and DMF in a ratio of 13.5-14 g: 30-35 mL; the amount ratio of product g9, DMF, ethanol, aqueous acetic acid, and zinc granules is 45-46 g: 55-65 mL: 35-45 mL: 18-22 mL: 3.5-4 g; the concentration of aqueous acetic acid is 1.8-2.0 mol / L; the volume fraction of ethanol is 95%; In the step G4 reaction process, the carboxyl group of sodium carboxybenzenesulfonate is converted into acyl chloride to obtain product g8; the acyl chloride of product g8 reacts with the secondary alcohol hydroxyl group of product g7 to obtain product g9; the phenolic ether of product g9 is converted into phenolic hydroxyl group to obtain product g10; In the step G5, zinc chloride and aluminum chloride hexahydrate are added into deionized water, stirred for 5-10 min, and then a 10-15% sodium hydroxide solution is used to adjust the pH to 9-10; the mixture is stirred at 70-80°C for 2-2.5 h, and then aged for 12-13 h; the product is washed until neutral, and then dried at 80-85°C for 7-7.5 h to obtain zinc-aluminum hydrotalcite; the zinc-aluminum hydrotalcite and product g10 are added into solvent 1, ultrasonically dispersed for 20-30 min, and then stirred to adjust the pH to 5.5-6; the mixture is stirred at 80-85°C for 4-4.5 h, and then washed until neutral; the product is dried at 70-75°C to obtain modified hydrotalcite; Further, the amount ratio of zinc chloride, aluminum chloride hexahydrate, and deionized water is 0.2-0.25 mol: 0.1-0.14 mol: 80-85 mL; the amount ratio of zinc-aluminum hydrotalcite, product g10, and solvent 1 is 6.5-7.5 g: 1.3-1.5 g: 30-40 mL; the solvent 1 is obtained by mixing ethanol and water in a volume ratio of 2-2.5: 1; the volume fraction of ethanol is 95%; In the step G5 reaction process, the zinc-aluminum hydrotalcite is prepared by a coprecipitation method, and then the sodium sulfonate of product g10 is used to intercalate and modify the zinc-aluminum hydrotalcite to obtain modified hydrotalcite; The preparation of the additive includes the following steps: In the step H1, the nano ferriferrous oxide is added into anhydrous ethanol, ultrasonically dispersed, and then hydrogen peroxide solution is added; the mixture is heated and stirred to obtain a pretreated product; the pretreated product is added into ethanol, ultrasonically dispersed, and then silane hydrolysis solution is added; the mixture is heated and stirred to obtain product h1; Step H2, carbon nanotubes, acid mixture, heated to reflux stirring to obtain product h2; product h1, anhydrous ethanol, DMF, triethylamine mixture, after stirring into the product h2, heating stirring to obtain product h3; Step H3, triphenylphosphine, bromo alcohol, anhydrous acetonitrile mixture, into the protective gas, heated stirring to obtain product h4; product h4, epichlorohydrin, methanol, DMSO mixture, stirring into the sodium hydroxide aqueous solution, heated stirring to obtain product h5; Step H4, product h3, acetonitrile, methanol mixture ultrasonic dispersion, into the N, N- dimethylbutylamine and product h5, heating reflux stirring to obtain product h6; product h6, potassium carbonate, DMSO, acetonitrile mixture ultrasonic dispersion, in ice water bath into the acryloyl chloride mixture, after heating stirring to obtain the adjuvant; The preparation of the adjuvant includes the following specific steps: Step H1, the nano four iron oxide is added into anhydrous ethanol, ultrasonic dispersion for 30-35 min, dropwise hydrogen peroxide solution, heated to 45-50 DEG C, stirring reaction 1-1.2 h, obtain pretreatment product; the pretreatment product is added into ethanol, ultrasonic dispersion for 25-30 min, add silane hydrolysis solution, stirring at 60-65 DEG C for 4-4.5 h, obtain product h1; Further, the nano four iron oxide, anhydrous ethanol, hydrogen peroxide solution is used in the ratio of 1-2 g: 35-45 mL: 30-40 mL; the mass fraction of hydrogen peroxide solution is 5-10%; the pretreatment product, ethanol, silane hydrolysis solution is used in the ratio of 1.5-2.5 g: 40-45 mL: 25-30 mL; the silane hydrolysis solution is obtained by mixing and stirring silane and solvent a, adjusting pH to 5-5.5, and then stirring at room temperature for 1.5-2 h; the silane is 5,6-epoxyhexyl triethoxysilane; the volume fraction of ethanol is 95%; the silane, solvent a in the silane hydrolysis solution is used in the ratio of 14-14.5 g: 30-32 mL; the solvent a is obtained by mixing ethanol and water in the volume ratio of 1-1.5: 1; In the process of step H1, the nano four iron oxide is treated by hydrogen peroxide solution, and the surface hydroxyl and other oxygen-containing functional groups are increased to obtain the pretreatment product; then the pretreatment product is treated by silane hydrolysis solution to obtain the nano four iron oxide containing epoxy group on the surface, i.e. product h1; Step H2, carbon nanotubes, acid mixture, heated to 80-85 DEG C, reflux stirring 1-1.2 h, obtain product h2; product h1, anhydrous ethanol, DMF, triethylamine mixture, stirring 35-40 min after adding product h2, stirring at 80-90 DEG C for 10-10.5 h, heating to 100-110 DEG C, continue stirring 2-2.2 h, obtain product h3; Further, the amount ratio of carbon nanotubes and acid solution is 1-1.5g:30-40mL; the acid solution is obtained by mixing concentrated nitric acid with mass fraction of 68% and concentrated sulfuric acid with mass fraction of 98% according to the volume ratio of 1-3:2-3; the amount ratio of product h1, anhydrous ethanol, DMF, triethylamine, product h2 is 2-2.5g:25-35mL:90-100mL:1-1.2g:3-4g; In the reaction process of step H2, the carbon nanotubes are treated with acid solution to obtain carboxylated carbon nanotubes, i.e. product h2; the carboxyl group of product h2 reacts with the epoxy group of product h1 to obtain the grafted product of carbon nanotubes containing secondary alcohol hydroxyl and nanometer ferroferric oxide, i.e. product h3; In step H3, triphenylphosphine, brominated alcohol and anhydrous acetonitrile are mixed, protective gas is introduced, and the mixture is heated to 40-45°C under stirring, and stirred for 24-24.5h to obtain product h4; product h4, epichlorohydrin, methanol and DMSO are mixed, and aqueous sodium hydroxide solution is added under stirring, and the mixture is heated to 55-60°C, and stirred for 4.5-5h to obtain product h5; Further, the amount ratio of triphenylphosphine, brominated alcohol and anhydrous acetonitrile is 14-14.5g:9-9.5g:60-70mL; the brominated alcohol is 5-bromo-1-pentanol; the amount ratio of product h4, epichlorohydrin, methanol, DMSO and aqueous sodium hydroxide solution is 24-25g:5-5.5g:15-20mL:50-55mL:30-35mL; the mass fraction of aqueous sodium hydroxide solution is 20-25%; In the reaction process of step H3, triphenylphosphine and brominated alcohol generate quaternary phosphonium salt containing primary alcohol through nucleophilic substitution reaction, i.e. product h4; the primary alcohol hydroxyl group of product h4 opens ring after ring-closing with epichlorohydrin to obtain product h5 containing epoxy group; In step H4, product h3, acetonitrile and methanol are mixed and ultrasonically dispersed for 40-50min, N,N-dimethylbutylamine and product h5 are added, and the mixture is refluxed and stirred at 90-100°C for 6-6.5h to obtain product h6; product h6, potassium carbonate, DMSO and acetonitrile are mixed and ultrasonically dispersed for 1-1.2h, acryloyl chloride mixture solution is added in ice water bath, and the temperature is increased to 50-55°C, and the mixture is stirred for 12-12.5h to obtain the additive; Further, the amount ratio of product h3, acetonitrile, methanol, N,N-dimethylbutylamine and product h5 is 7-8g:150-160mL:20-30mL:0.7-0.9g:15-16g; the amount ratio of product h6, potassium carbonate, DMSO, acetonitrile and acryloyl chloride mixture solution is 25-26g:2-2.5g:170-180mL:35-45mL:35-40mL; the acryloyl chloride mixture solution is obtained by mixing acryloyl chloride and DMSO according to the ratio of 4.6-5g:15-20mL. In the reaction process of step H4, the secondary alcohol of product h3 reacts with the epoxy group of product h5 to obtain a product h6 containing a hydroxyl group; and acryloyl chloride reacts with the hydroxyl group of product h6 to obtain an auxiliary containing a terminal carbon-carbon double bond; The spiral modified MBBR filler disclosed by the application has a high fluidization rate, which helps to reduce energy consumption.

[0009] The modified hydrotalcite is obtained by intercalating a product obtained by the reaction of thiophene formaldehyde, nitroimidazole, aldehyde pyrimidine, sodium carboxybenzenesulfonate, etc. into zinc-aluminum hydrotalcite; the use of thiophene formaldehyde, nitroimidazole and aldehyde pyrimidine forms a conjugated system containing thiophene and nitrogen-containing heterocycle with strong conjugation effect, which widens the ultraviolet absorption range, improves the defect of small ultraviolet absorption range of thiophene, enhances ultraviolet absorption and converts it into other energy to release, and the hydroxyl group formed on the pyrimidine ring has free radical capturing ability to terminate chain reaction and has strong anti-aging property; after being combined with zinc-aluminum hydrotalcite intercalated with the product obtained by the reaction of sodium carboxybenzenesulfonate, etc., the positive charge on the surface of the zinc-aluminum hydrotalcite helps the modified hydrotalcite to be attracted to the microorganisms with negative charges through positive and negative charges, enhances the adsorption and fixation between the filler and the microorganisms, and thus improves the biofilm formation speed; the zinc-aluminum hydrotalcite has the ability to physically block ultraviolet rays, cooperates with the conjugated system and the hydroxyl group on the pyrimidine ring to avoid ultraviolet damage to the filler, further endows the filler with strong anti-aging property, and prolongs the service life of the filler.

[0010] The auxiliary is a product obtained by the reaction of silane-modified nano-ferroferric oxide, carboxylated carbon nanotube, triphenylphosphine, bromoalcohol and acryloyl chloride; the use of silane-modified nano-ferroferric oxide and carboxylated carbon nanotube physically isolates the carbon nanotube, reduces the contact probability of salt ions such as chloride ions and sulfate ions with iron active sites, utilizes the magnetism of ferroferric oxide and the conductivity of carbon nanotube to form a heterojunction interface, accelerates electron transfer, improves catalytic activity, and makes up for the deficiency of the decline in catalytic activity caused by the dissolution of ferroferric oxide accelerated by salt ions such as chloride ions and sulfate ions; the use of triphenylphosphine and bromoalcohol forms a quaternary phosphonium salt in the auxiliary, which enhances the hydrophilicity of the surface of HDPE after the auxiliary is melt-grafted with HDPE, and reduces the difficulty of initial adhesion of microorganisms to the filler; after the auxiliary is melt-grafted with HDPE, the compatibility of nano-ferroferric oxide, carbon nanotube and modified hydrotalcite containing a hydroxyl group with the matrix is greatly improved, which helps to form a uniform whole, avoids uneven fluidization of the filler caused by too large a density gap between nano-ferroferric oxide and HDPE, simultaneously avoids peeling of ferroferric oxide particles caused by excessive friction, and improves the stability of the biofilm.

[0011] The present application greatly improves the hydraulic performance of the filler by adopting a three-dimensional spiral structure design. The unique three-dimensional morphology can effectively destroy the water flow stability, promote the formation of turbulent flow in the reactor, enhance the gas-liquid-solid three-phase mixing efficiency, avoid short flow and filler accumulation, significantly improve the mass transfer effect and oxygen utilization, and achieve good fluidization at lower aeration intensity, effectively reducing the energy consumption of the system operation. Secondly, the spiral structure significantly increases the specific surface area of the filler and provides diverse spatial niches for microbial attachment. Combined with the modified high biological affinity surface, it is more conducive to the initial colonization of microorganisms and the stable formation of biofilm, which can accelerate the start-up process of biofilm, improve the total amount of biofilm and population diversity, and thus enhance the simultaneous removal capacity of various pollutants such as COD, TN, TP, etc. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 is a side view of the spiral modified MBBR filler (28) of the present application embodiment 7-9; the side wall of the spiral modified MBBR filler (28) is opened as a three-dimensional spiral flow channel (281).

[0013] Figure 2 is a top view of the spiral modified MBBR filler (28) of the present application embodiment 7-9. DETAILED DESCRIPTION

[0014] The technical solutions in the embodiments of the present application will be described below in a clear and complete manner. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0015] Embodiment 1 A modified hydrotalcite, the preparation thereof comprising the following specific steps: Step G1, 3-thiophene carboxaldehyde was added to acetic anhydride, stirred for 5 min, then anhydrous potassium carbonate was added to start reflux, heated to 95°C, stirred for 2.5 h to obtain product g1; product g1 was added to DMF, stirred, dichlorosulfoxide was added, heated to 55°C, refluxed and stirred for 4 h to obtain product g2; 4-nitroimidazole, DMSO were mixed, stirred for 20 min, product g2 mixture was added dropwise in an ice water bath, heated to 50°C after addition was completed, stirred for 7.5 h to obtain product g3; the amount ratio of 3-thiophene carboxaldehyde, acetic anhydride, anhydrous potassium carbonate was 5.8 g: 5 g: 1.4 g; the amount ratio of product g1, DMF, dichlorosulfoxide was 6.5 g: 30 mL: 6 g; the amount ratio of 4-nitroimidazole, DMSO, product g2 mixture was 5.9 g: 13 mL: 25 mL; the product g2 mixture was obtained by mixing product g2 and DMSO according to a ratio of 7.5 g: 15 mL; Step G2, product g3, DMAC, ethanol solution were mixed, stirred for 30 min, sodium dithionite was added, stirred at a pH of 8.1 and a temperature of 45°C for 2.8 h to obtain product g4; product g4, epichlorohydrin, DMF were mixed, stirred for 30 min, tetra-n-butylammonium chloride was added, stirred at 95°C for 2 h, then a base solution was added, continued to stir for 1.5 h to obtain product g5; the amount ratio of product g3, DMAC, ethanol solution, sodium dithionite was 13.5 g: 28 mL: 25 mL: 8.5 g; the ethanol solution was obtained by mixing ethanol with a volume fraction of 95% and water according to a volume ratio of 2:1; the amount ratio of product g4, epichlorohydrin, DMF, tetra-n-butylammonium chloride, base solution was 12 g: 9.6 g: 45 mL: 40 mg: 20 mL; the base solution was a potassium hydroxide or sodium hydroxide solution with a mass fraction of 40%; Step G3, 2-methoxy-5-aldehyde pyrimidine was added to acetic anhydride, stirred for 20 min, then anhydrous potassium carbonate was added to start reflux, heated to 90°C, stirred for 3.5 h to obtain product g6; product g6, DMAC, triethylamine were mixed, stirred for 35 min, product g5 was added, heated to 75°C, stirred for 7.5 h, then heated to 105°C, continued to stir for 1.5 h to obtain product g7; the amount ratio of 2-methoxy-5-aldehyde pyrimidine, acetic anhydride, anhydrous potassium carbonate was 7.0 g: 5. g: 1.8 g; the amount ratio of product g6, DMAC, triethylamine, product g5 was 7.8 g: 65 mL: 0.2 g: 22.5 g; Step G4, sodium 3-carboxybenzenesulfonate, DMSO, ethanol were mixed and stirred at 35℃ for 30 min, then thionyl chloride was added, and the reaction was stirred at 60℃ for 2.5 h to obtain product g8; product g7, ethyl acetate, DMAC were mixed and stirred for 40 min, then the mixed solution of product g8 was added in an ice water bath, and the reaction was stirred at 70℃ for 10 h to obtain product g9; product g9, DMF, ethanol were mixed and stirred at reflux for 30 min, then aqueous acetic acid and zinc granules were added, and the reaction was stirred at 85℃ for 2 h to obtain product g10; the amount ratio of sodium 3-carboxybenzenesulfonate, DMSO, ethanol, thionyl chloride was 11.5 g: 25 mL: 15 mL: 7.5 g; the volume fraction of ethanol was 95%; the amount ratio of the mixed solution of product g7, ethyl acetate, DMAC, product g8 was 30 g: 20 mL: 40 mL: 45 mL; the mixed solution of product g8 was obtained by mixing product g8 and DMF in a ratio of 13.5 g: 30 mL; the amount ratio of product g9, DMF, ethanol, aqueous acetic acid, zinc granules was 45 g: 55 mL: 35 mL: 18 mL: 3.5 g; the concentration of aqueous acetic acid was 1.8 mol / L; the volume fraction of ethanol was 95%; Step G5, zinc chloride and aluminum chloride hexahydrate were added into deionized water, stirred for 5 min, and then the pH was adjusted to 9 with 10% sodium hydroxide solution, and the reaction was stirred at 70℃ for 2 h, and then aged for 12 h, washed to neutral, and dried at 80℃ for 7 h to obtain zinc-aluminum hydrotalcite; the zinc-aluminum hydrotalcite and product g10 were added into solvent 1, ultrasonically dispersed for 20 min, the pH was adjusted to 5.5, and the reaction was stirred at 80℃ for 4 h, washed to neutral, and dried at 70℃ to obtain modified hydrotalcite; the amount ratio of zinc chloride, aluminum chloride hexahydrate, deionized water was 0.2 mol: 0.1 mol: 80 mL; the amount ratio of zinc-aluminum hydrotalcite, product g10, solvent 1 was 6.5 g: 1.3 g: 30 mL; solvent 1 was obtained by mixing ethanol and water in a volume ratio of 2:1; the volume fraction of ethanol was 95%.

[0016] Example 2 A modified hydrotalcite, the preparation comprising the following specific steps: Step G1, 3-thiophene carboxaldehyde was added to acetic anhydride, stirred for 8 min, then anhydrous potassium carbonate was added to start reflux, heated to 100°C, stirred for 2.8 h to obtain product g1; product g1 was added to DMF, then thionyl chloride was added with stirring, heated to 58°C, refluxed and stirred for 4.3 h to obtain product g2; 4-nitroimidazole, DMSO were mixed, stirred for 23 min, then product g2 mixture was added dropwise in an ice-water bath, heated to 53°C after addition was completed, stirred for 7.8 h to obtain product g3; the amount ratio of 3-thiophene carboxaldehyde, acetic anhydride, anhydrous potassium carbonate was 6.0 g:5.2 g:1.7 g; the amount ratio of product g1, DMF, thionyl chloride was 6.8 g:33 mL:6.3 g; the amount ratio of 4-nitroimidazole, DMSO, product g2 mixture was 6.1 g:14 mL:28 mL; the product g2 mixture was obtained by mixing product g2 and DMSO according to a ratio of 7.8 g:17 mL; Step G2, product g3, DMAC, ethanol solution were mixed, stirred for 33 min, then sodium dithionite was added, stirred at a pH of 8.2 and a temperature of 48°C for 3.0 h to obtain product g4; product g4, epichlorohydrin, DMF were mixed, stirred for 35 min, then tetra-n-butylammonium chloride was added, stirred at 98°C for 2.5 h, then a base solution was added, continued to stir for 1.8 h to obtain product g5; the amount ratio of product g3, DMAC, ethanol solution, sodium dithionite was 14.0 g:30 mL:28 mL:8.8 g; the ethanol solution was obtained by mixing ethanol with a volume fraction of 95% and water according to a volume ratio of 2.3:1.3; the amount ratio of product g4, epichlorohydrin, DMF, tetra-n-butylammonium chloride, base solution was 12.3 g:9.8 g:50 mL:45 mg:22 mL; the base solution was a potassium hydroxide or sodium hydroxide solution with a mass fraction of 43%; Step G3, 2-methoxy-5-formylpyrimidine was added to acetic anhydride, stirred for 23 min, then anhydrous potassium carbonate was added to start reflux, heated to 95°C, stirred for 3.8 h to obtain product g6; product g6, DMAC, triethylamine were mixed, stirred for 38 min, then product g5 was added, heated to 80°C, stirred for 7.8 h, then heated to 107°C, continued to stir for 1.6 h to obtain product g7; the amount ratio of 2-methoxy-5-formylpyrimidine, acetic anhydride, anhydrous potassium carbonate was 7.3 g:5.8 g:2.0 g; the amount ratio of product g6, DMAC, triethylamine, product g5 was 8.0 g:68 mL:0.25 g:22.8 g; Step G4, sodium 3-carboxybenzenesulfonate, DMSO, ethanol were mixed, stirred at 38℃ for 35min, then added with SOCl2, stirred at 63℃ for 2.8h to obtain product g8; product g7, ethyl acetate, DMAC were mixed, stirred for 43min, then added with the mixture of product g8 in ice water bath, heated to 75℃, stirred at reflux for 10.3h to obtain product g9; product g9, DMF, ethanol were mixed, stirred at reflux for 33min, then added with aqueous acetic acid and zinc granules, stirred at reflux at 88℃ for 2.3h to obtain product g10; the amount ratio of sodium 3-carboxybenzenesulfonate, DMSO, ethanol, SOCl2 was 11.8g:28mL:18mL:7.8g; the volume fraction of ethanol was 95%; the amount ratio of product g7, ethyl acetate, DMAC, product g8 mixture was 30.5g:23mL:43mL:48mL; the mixture of product g8 was obtained by mixing product g8 and DMF according to the ratio of 13.8g:33mL; the amount ratio of product g9, DMF, ethanol, aqueous acetic acid, zinc granules was 45.5g:60mL:40mL:20mL:3.8g; the concentration of aqueous acetic acid was 1.9mol / L; the volume fraction of ethanol was 95%; Step G5, zinc chloride, aluminum chloride hexahydrate were added into deionized water, stirred for 8min, then the pH was adjusted to 9.5 with 13% sodium hydroxide solution, stirred at 75℃ for 2.3h, then aged for 12.5h, washed to neutral, dried at 83℃ for 7.3h to obtain zinc-aluminum hydrotalcite; the zinc-aluminum hydrotalcite and product g10 were added into solvent 1, ultrasonically dispersed for 25min, then the pH was adjusted to 5.8, stirred at 83℃ for 4.3h, washed to neutral, dried at 73℃ to obtain modified hydrotalcite; the amount ratio of zinc chloride, aluminum chloride hexahydrate, deionized water was 0.23mol:0.12mol:83mL; the amount ratio of zinc-aluminum hydrotalcite, product g10, solvent 1 was 7.0g:1.4g:35mL; solvent 1 was obtained by mixing ethanol and water according to the volume ratio of 2.3:1; the volume fraction of ethanol was 95%.

[0017] Example 3 A modified hydrotalcite, the preparation comprising the following specific steps: Step G1, 3-thiophene carboxaldehyde was added to acetic anhydride, stirred for 10 min, then anhydrous potassium carbonate was added to start reflux, the temperature was raised to 105°C, and stirred for 3 h to obtain product g1; product g1 was added to DMF, and thionyl chloride was added while stirring, and heated to 60°C, and stirred for 4.5 h to obtain product g2; 4-nitroimidazole and DMSO were mixed, and stirred for 25 min, then product g2 was added dropwise in an ice-water bath, and heated to 55°C after the addition was completed, and stirred for 8 h to obtain product g3; the amount ratio of 3-thiophene carboxaldehyde, acetic anhydride and anhydrous potassium carbonate was 6.2 g: 5.4 g: 2.0 g; the amount ratio of product g1, DMF and thionyl chloride was 7 g: 35 mL: 6.5 g; the amount ratio of 4-nitroimidazole, DMSO and product g2 was 6.3 g: 15 mL: 30 mL; the mixture of product g2 was obtained by mixing product g2 and DMSO in a ratio of 8 g: 20 mL; Step G2, product g3, DMAC and ethanol solution were mixed, stirred for 35 min, then sodium dithionite was added, and stirred at a pH of 8.5 and a temperature of 50°C for 3.2 h to obtain product g4; product g4, epichlorohydrin and DMF were mixed, stirred for 40 min, then tetra-n-butylammonium chloride was added, and stirred at 100°C for 3 h, then a base solution was added, and stirred for another 2 h to obtain product g5; the amount ratio of product g3, DMAC, ethanol solution and sodium dithionite was 14.5 g: 32 mL: 30 mL: 9 g; the ethanol solution was obtained by mixing ethanol with a volume fraction of 95% and water in a volume ratio of 2.5: 1.5; the amount ratio of product g4, epichlorohydrin, DMF, tetra-n-butylammonium chloride and base solution was 12.5 g: 10.0 g: 55 mL: 50 mg: 24 mL; the base solution was a potassium hydroxide or sodium hydroxide solution with a mass fraction of 45%; Step G3, 2-methoxy-5-formylpyrimidine was added to acetic anhydride, stirred for 25 min, then anhydrous potassium carbonate was added to start reflux, the temperature was raised to 100°C, and stirred for 4 h to obtain product g6; product g6, DMAC and triethylamine were mixed, stirred for 40 min, then product g5 was added, and heated to 85°C, and stirred for 8 h, and then the temperature was raised to 110°C, and stirred for another 1.7 h to obtain product g7; the amount ratio of 2-methoxy-5-formylpyrimidine, acetic anhydride and anhydrous potassium carbonate was 7.5 g: 6 g: 2.2 g; the amount ratio of product g6, DMAC, triethylamine and product g5 was 8.2 g: 70 mL: 0.3 g: 23 g; Step G4, sodium 3-carboxybenzenesulfonate, DMSO, ethanol were mixed and stirred at 40℃ for 40 min, then thionyl chloride was added, and the reaction was stirred at 65℃ for 3h to obtain product g8; product g7, ethyl acetate, DMAC were mixed and stirred for 45 min, then the mixture of product g8 was added in ice water bath, and the reaction was stirred at 80℃ for 10.5h to obtain product g9; product g9, DMF, ethanol were mixed and stirred at reflux for 35 min, then acetic acid aqueous solution and zinc granules were added, and the reaction was stirred at 90℃ for 2.5h to obtain product g10; the amount ratio of sodium 3-carboxybenzenesulfonate, DMSO, ethanol, thionyl chloride was 12g:30mL:20mL:8g; the volume fraction of ethanol was 95%; the amount ratio of product g7, ethyl acetate, DMAC, the mixture of product g8 was 31g:25mL:45mL:50mL; the mixture of product g8 was obtained by mixing product g8 and DMF according to the ratio of 14g:35mL; the amount ratio of product g9, DMF, ethanol, acetic acid aqueous solution, zinc granules was 46g:65mL:45mL:22mL:4g; the concentration of acetic acid aqueous solution was 2.0mol / L; the volume fraction of ethanol was 95%; Step G5, zinc chloride, aluminum chloride hexahydrate were added into deionized water, stirred for 10 min, then the pH was adjusted to 10 with 15% sodium hydroxide solution, and the reaction was stirred at 80℃ for 2.5h, then aged for 13h, washed to neutral, and dried at 85℃ for 7.5h to obtain zinc-aluminum hydrotalcite; the zinc-aluminum hydrotalcite and product g10 were added into solvent 1, ultrasonically dispersed for 30 min, the pH was adjusted to 6, and the reaction was stirred at 85℃ for 4.5h, then washed to neutral, and dried at 75℃ to obtain modified hydrotalcite; the amount ratio of zinc chloride, aluminum chloride hexahydrate, deionized water was 0.25mol:0.14mol:85mL; the amount ratio of zinc-aluminum hydrotalcite, product g10, solvent 1 was 7.5g:1.5g:40mL; solvent 1 was obtained by mixing ethanol and water according to the volume ratio of 2.5:1; the volume fraction of ethanol was 95%.

[0018] Example 4 An auxiliary, the preparation comprising the following steps: Step H1, the nano four iron oxide was added into anhydrous ethanol and ultrasonic dispersed for 30 min, hydrogen peroxide solution was added dropwise, heated to 45℃, and stirred for 1 h to obtain a pretreatment product; the pretreatment product was added into ethanol and ultrasonic dispersed for 25 min, a silane hydrolyzate was added, and stirred at 60℃ for 4 h to obtain product h1; the amount ratio of the nano four iron oxide, anhydrous ethanol and hydrogen peroxide solution was 1 g: 35 mL: 30 mL; the mass fraction of the hydrogen peroxide solution was 5%; the amount ratio of the pretreatment product, ethanol and silane hydrolyzate was 1.5 g: 40 mL: 25 mL; the silane hydrolyzate was obtained by mixing 5,6-epoxyhexyl triethoxysilane and solvent a, adjusting pH to 5.1, and then stirring at room temperature for 1.5 h; the amount ratio of 5,6-epoxyhexyl triethoxysilane and solvent a in the silane hydrolyzate was 14 g: 30 mL; the solvent a was obtained by mixing ethanol and water in a volume ratio of 1:1; the volume fraction of ethanol was 95%; Step H2, the carbon nanotube and acid solution were mixed, heated to 80℃, and stirred for 1 h to obtain product h2; product h1, anhydrous ethanol, DMF and triethylamine were mixed, stirred for 35 min, then product h2 was added, stirred at 80℃ for 10 h, heated to 100℃, and then stirred for 2 h to obtain product h3; the amount ratio of the carbon nanotube and acid solution was 1 g: 30 mL; the acid solution was obtained by mixing concentrated nitric acid with a mass fraction of 68% and concentrated sulfuric acid with a mass fraction of 98% in a volume ratio of 1:2; the amount ratio of product h1, anhydrous ethanol, DMF, triethylamine and product h2 was 2 g: 25 mL: 90 mL: 1 g: 3 g; Step H3, triphenylphosphine, 5-bromo-1-pentanol and anhydrous acetonitrile were mixed, nitrogen was introduced, heated to 40℃ under stirring, and stirred for 24 h to obtain product h4; product h4, epichlorohydrin, methanol, DMSO and sodium hydroxide aqueous solution were mixed, heated to 55℃ under stirring, and stirred for 4.5 h to obtain product h5; the amount ratio of triphenylphosphine, 5-bromo-1-pentanol and anhydrous acetonitrile was 14 g: 9 g: 60 mL; the amount ratio of product h4, epichlorohydrin, methanol, DMSO and sodium hydroxide aqueous solution was 24 g: 5 g: 15 mL: 50 mL: 30 mL; the mass fraction of the sodium hydroxide aqueous solution was 20%; Step H4, product h3, acetonitrile, methanol were mixed and ultrasonically dispersed for 40 min, N,N-dimethylbutylamine and product h5 were added, and the reaction was stirred at 90℃ for 6h to obtain product h6; product h6, potassium carbonate, DMSO, acetonitrile were mixed and ultrasonically dispersed for 1h, acryloyl chloride mixture was added in an ice water bath, and after the addition was completed, the temperature was increased to 50℃, and the reaction was stirred for 12h to obtain the adjuvant; the amount ratio of product h3, acetonitrile, methanol, N,N-dimethylbutylamine, product h5 was 7g: 150mL: 20mL: 0.7g: 15g; the amount ratio of product h6, potassium carbonate, DMSO, acetonitrile, acryloyl chloride mixture was 25g: 2g: 170mL: 35mL: 35mL; the acryloyl chloride mixture was obtained by mixing acryloyl chloride and DMSO in a ratio of 4.6g: 15mL.

[0019] Example 5 An adjuvant, the preparation comprising the following steps: Step H1, nano four-iron oxide was added to anhydrous ethanol and ultrasonically dispersed for 33 min, hydrogen peroxide solution was added dropwise, heated to 48℃, and stirred for 1.1h to obtain a pretreated product; the pretreated product was added to ethanol and ultrasonically dispersed for 28 min, and a silane hydrolysis solution was added, and stirred at 63℃ for 4.3h to obtain product h1; the amount ratio of nano four-iron oxide, anhydrous ethanol, hydrogen peroxide solution was 1.5g: 40mL: 35mL; the mass fraction of hydrogen peroxide solution was 8%; the amount ratio of pretreated product, ethanol, silane hydrolysis solution was 2.0g: 43mL: 28mL; the silane hydrolysis solution was obtained by mixing 5,6-epoxyhexyl triethoxysilane and solvent a, adjusting the pH to 5.2, and then stirring at room temperature for 1.8h; the amount ratio of 5,6-epoxyhexyl triethoxysilane and solvent a in the silane hydrolysis solution was 14.3g: 31mL; the solvent a was obtained by mixing ethanol and water in a volume ratio of 1.3: 1; the volume fraction of ethanol was 95%; Step H2, carbon nanotubes and acid solution were mixed and heated to 83℃, and stirred at reflux for 1.1h to obtain product h2; product h1, anhydrous ethanol, DMF, triethylamine were mixed and stirred for 38 min, and then product h2 was added, and stirred at 85℃ for 10.3h, and then the temperature was increased to 105℃ and the stirring was continued for 2.1h to obtain product h3; the amount ratio of carbon nanotubes and acid solution was 1.3g: 35mL; the acid solution was obtained by mixing concentrated nitric acid with a mass fraction of 68% and concentrated sulfuric acid with a mass fraction of 98% in a volume ratio of 2: 2.5; the amount ratio of product h1, anhydrous ethanol, DMF, triethylamine, product h2 was 2.3g: 30mL: 95L: 1.1g: 3.5g; Step H3, triphenylphosphine, 5-bromo-1-pentanol, anhydrous acetonitrile were mixed, nitrogen was bubbled, heated to 43℃ under stirring, the reaction was stirred for 24.3h to obtain product h4; product h4, epichlorohydrin, methanol, DMSO were mixed, aqueous sodium hydroxide solution was added under stirring, heated to 58℃, the reaction was stirred for 4.8h to obtain product h5; the amount ratio of triphenylphosphine, 5-bromo-1-pentanol, anhydrous acetonitrile was 14.3g:9.3g:65mL; the amount ratio of product h4, epichlorohydrin, methanol, DMSO, aqueous sodium hydroxide solution was 24.5g:5.3g:18mL:53mL:33mL; the mass fraction of aqueous sodium hydroxide solution was 23%; Step H4, product h3, acetonitrile, methanol were mixed and ultrasonically dispersed for 45min, N,N-dimethylbutylamine and product h5 were added, the reaction was stirred at 95℃ for 6.3h to obtain product h6; product h6, potassium carbonate, DMSO, acetonitrile were mixed and ultrasonically dispersed for 1.1h, acryloyl chloride mixture was added in an ice-water bath, after the addition, the temperature was increased to 53℃, the reaction was stirred for 12.3h to obtain the adjuvant; the amount ratio of product h3, acetonitrile, methanol, N,N-dimethylbutylamine, product h5 was 7.5g:155mL:25mL:0.8g:15.5g; the amount ratio of product h6, potassium carbonate, DMSO, acetonitrile, acryloyl chloride mixture was 25.5g:2.3g:175mL:40mL:38mL; the acryloyl chloride mixture was obtained by mixing acryloyl chloride and DMSO in a ratio of 4.8g:18mL.

[0020] Example 6 An adjuvant, the preparation comprising the following steps: Step H1, nano-magnetite was added into anhydrous ethanol, ultrasonically dispersed for 35min, hydrogen peroxide solution was added dropwise, heated to 50℃, the reaction was stirred for 1.2h to obtain pretreated product; the pretreated product was added into ethanol, ultrasonically dispersed for 30min, silane hydrolysis solution was added, stirred at 65℃ for 4.5h to obtain product h1; the amount ratio of nano-magnetite, anhydrous ethanol, hydrogen peroxide solution was 2g:45mL:40mL; the mass fraction of hydrogen peroxide solution was 10%; the amount ratio of pretreated product, ethanol, silane hydrolysis solution was 2.5g:45mL:30mL; the silane hydrolysis solution was obtained by mixing 5,6-epoxyhexyltriethoxysilane and solvent a under stirring, adjusting pH to 5.5, and then stirring at room temperature for 2h; the amount ratio of 5,6-epoxyhexyltriethoxysilane and solvent a in the silane hydrolysis solution was 14.5g:32mL; the solvent a was obtained by mixing ethanol and water in a volume ratio of 1.5:1; the volume fraction of ethanol was 95%; Step H2: Mix carbon nanotubes and acid solution, heat to 85℃, and reflux and stir for 1.2h to obtain product h2; mix product h1, anhydrous ethanol, DMF, and triethylamine, stir for 40min, add product h2, stir at 90℃ for 10.5h, raise the temperature to 110℃, and continue stirring for 2.2h to obtain product h3; the ratio of carbon nanotubes to acid solution is 1.5g:40mL; the acid solution is a mixture of 68% concentrated nitric acid and 98% concentrated sulfuric acid in a volume ratio of 3:2.8; the ratio of product h1, anhydrous ethanol, DMF, triethylamine, and product h2 is 2.5g:35mL:100mL:1.2g:4g. Step H3: Triphenylphosphine, 5-bromo-1-pentanol, and anhydrous acetonitrile were mixed, nitrogen gas was introduced, and the mixture was heated to 45°C with stirring for 24.5 h to obtain product h4. Product h4, epichlorohydrin, methanol, and DMSO were mixed, and sodium hydroxide aqueous solution was added with stirring. The mixture was heated to 60°C and stirred for 5 h to obtain product h5. The molar ratio of triphenylphosphine, 5-bromo-1-pentanol, and anhydrous acetonitrile was 14.5 g: 9.5 g: 70 mL; the molar ratio of product h4, epichlorohydrin, methanol, DMSO, and sodium hydroxide aqueous solution was 25 g: 5.5 g: 20 mL: 55 mL: 35 mL; the mass fraction of sodium hydroxide aqueous solution was 25%. Step H4: Mix product h3, acetonitrile, and methanol and ultrasonically disperse for 50 min. Add N,N-dimethylbutylamine and product h5, and reflux and stir at 100℃ for 6.5 h to obtain product h6. Mix product h6, potassium carbonate, DMSO, and acetonitrile and ultrasonically disperse for 1.2 h. Add acryloyl chloride mixture in an ice-water bath. After addition, raise the temperature to 55℃ and stir for 12.5 h to obtain the auxiliary agent. The ratio of product h3, acetonitrile, methanol, N,N-dimethylbutylamine, and product h5 is 8 g: 160 mL: 30 mL: 0.9 g: 16 g. The ratio of product h6, potassium carbonate, DMSO, acetonitrile, and acryloyl chloride mixture is 26 g: 2.5 g: 180 mL: 45 mL: 40 mL. The acryloyl chloride mixture is obtained by mixing acryloyl chloride and DMSO at a ratio of 5 g: 20 mL.

[0021] Example 7 like Figure 1 The spiral modified MBBR filler shown comprises the following raw materials in parts by weight: 100 parts HDPE, 7 parts modified hydrotalcite, 4 parts additives, 0.7 parts initiator, 1 part polyvinyl alcohol, 1 part chitosan, 1.5 parts gelatin, 5 parts activated carbon, 0.5 parts zinc stearate, and 0.3 parts EBS dispersant; the initiator is dicumyl peroxide. The spiral-shaped modified MBBR packing is prepared by the following steps: HDPE (supplier: Dongguan Aolei Plastics Co., Ltd., specification 25kg) and the additives obtained in Example 4 were melt-mixed at 175°C. Then, an initiator was added, and the mixture was heated to 185°C and allowed to melt for 13 minutes. The mixture was then cooled to 80°C, and the modified hydrotalcite obtained in Example 1, polyvinyl alcohol (supplier: Zhengzhou Wandao New Material Technology Co., Ltd., specification 25kg), chitosan, gelatin, activated carbon, zinc stearate, and EBS dispersant were added and mixed at 800 rpm for 10 minutes. The mixture was then heated to 190°C and 300 rpm for melt blending, extruded and granulated, and then extruded by screw extrusion. The blank is formed into a cylindrical part at 180℃; then the cylindrical blank is cut with a carbide spiral cutter. After cutting, it is immersed in water at 75℃ for 1.8 hours, then dried at 60℃ for 4 hours, and then treated with plasma to obtain spiral modified MBBR filler. The diameter of the cylindrical blank is 10 mm and the length-to-diameter ratio is 0.8. The helix angle of the carbide spiral cutter is 30°, the cutter width is 2 mm, and the cutter depth is 1.5 mm. During the cutting process of the carbide spiral cutter, the linear speed is 0.5 m / s and the feed is 0.2 mm / r. The plasma treatment conditions are 300 W power and 90 s time.

[0022] Example 8 like Figure 1 The spiral-shaped modified MBBR filler shown comprises the following raw materials in parts by weight: 103 parts HDPE, 8 parts modified hydrotalcite, 5 parts additives, 0.8 parts initiator, 1.5 parts polyvinyl alcohol, 1.5 parts chitosan, 2.2 parts gelatin, 8 parts activated carbon, 0.8 parts zinc stearate, and 0.4 parts EBS dispersant; the initiator is dicumyl peroxide. The spiral-shaped modified MBBR packing is prepared by the following steps: HDPE (supplier: Dongguan Aolei Plastics Co., Ltd., specification 25kg) and the additives obtained in Example 5 were melt-mixed at 178°C. Then, an initiator was added, and the mixture was heated to 188°C and allowed to melt for 15 minutes. The mixture was then cooled to 85°C, and the modified hydrotalcite obtained in Example 2, polyvinyl alcohol (supplier: Zhengzhou Wandao New Material Technology Co., Ltd., specification 25kg), chitosan, gelatin, activated carbon, zinc stearate, and EBS dispersant were added. The mixture was then mixed at 900 rpm for 13 minutes, and then melt-blended at 195°C and 300 rpm. The resulting product was extruded and granulated using a screw extruder. The blank was formed into a cylindrical part at 95℃; then the cylindrical blank was cut with a carbide spiral cutter, and after cutting, it was immersed in water at 78℃ for 1.9h, then dried at 63℃ for 4.3h, and then treated with plasma to obtain spiral modified MBBR filler; the diameter of the cylindrical blank was 15mm and the length-to-diameter ratio was 1.0; the helix angle of the carbide spiral cutter was 45°, the cutter width was 3mm, and the cutter depth was 2.2mm; during the cutting process of the carbide spiral cutter, the linear speed was 1.0m / s and the feed was 0.3mm / r; the plasma treatment conditions were 400W power and 105s time.

[0023] Example 9 like Figure 1 The spiral modified MBBR filler shown comprises the following raw materials in parts by weight: 105 parts HDPE, 9 parts modified hydrotalcite, 6 parts additives, 0.9 parts initiator, 2 parts polyvinyl alcohol, 2 parts chitosan, 3 parts gelatin, 10 parts activated carbon, 1 part zinc stearate, and 0.5 parts EBS dispersant; the initiator is dicumyl peroxide. The spiral-shaped modified MBBR packing is prepared by the following steps: HDPE (supplier: Dongguan Aolei Plastics Co., Ltd., specification 25kg) and the additives obtained in Example 6 were melt-mixed at 180°C. Then, an initiator was added, and the mixture was heated to 190°C and allowed to melt for 17 minutes. The mixture was then cooled to 90°C, and the modified hydrotalcite obtained in Example 3, polyvinyl alcohol (supplier: Zhengzhou Wandao New Material Technology Co., Ltd., specification 25kg), chitosan, gelatin, activated carbon, zinc stearate, and EBS dispersant were added and mixed at 1000 rpm for 15 minutes. The mixture was then melt-blended at 200°C and 400 rpm, extruded and granulated, and then extruded through a screw extruder. The blank was formed into a cylindrical part at 210℃ using a press; then the cylindrical blank was sheared with a carbide spiral cutter, and after shearing, it was immersed in water at 80℃ for 2 hours, then dried at 65℃ for 4.5 hours, and then treated with plasma to obtain spiral modified MBBR filler; the diameter of the cylindrical blank was 25mm and the length-to-diameter ratio was 1.2; the helix angle of the carbide spiral cutter was 60°, the cutter width was 4mm, and the cutter depth was 3mm; during the shearing process of the carbide spiral cutter, the linear speed was 1.5m / s and the feed was 0.5mm / r; the plasma treatment conditions were 500W power and 120s time.

[0024] Comparative Example 1 Compared with Example 9, the 2-methoxy-5-aldehyde pyrimidine used in the preparation process of the modified hydrotalcite was replaced with 5-methoxypyridine-2-aldehyde, and the rest was exactly the same as in Example 9, to obtain the filler.

[0025] Comparative Example 2 Compared with Example 9, the 4-nitroimidazole used in the preparation process of the modified hydrotalcite was replaced with N-methyl-p-nitroaniline, and the rest was exactly the same as in Example 9, to obtain the filler.

[0026] Comparative Example 3 Compared with Example 9, the modified hydrotalcite used was replaced with modified hydrotalcite-1, that is, modified hydrotalcite-1 was obtained by reacting product g9 with zinc-aluminum hydrotalcite in step G5. The rest was exactly the same as in Example 9, and the filler was prepared.

[0027] Comparative Example 4 Compared with Example 9, the triphenylphosphine used in the preparation process of the auxiliary agent was replaced with triethylamine, and the rest was exactly the same as in Example 9, to obtain the filler.

[0028] Comparative Example 5 Compared with Example 9, the carbon nanotubes used in the preparation process of the additives were replaced with halloysite nanotubes, and the rest was exactly the same as in Example 9, to obtain the filler.

[0029] The filler prepared according to the present invention was further tested, and the test results are as follows.

[0030] The fillers obtained in Examples 7-9 and Comparative Examples 1-5 of the present application were respectively placed in the same fluidized bed reactor under the same conditions. A simulated sewage with high salt content (influent COD 300 mg / L, TN 40 mg / L, TP 4 mg / L, 25℃, DO 2-3 mg / L, NaCl 600 mg / L) was simulated, the filler loading rate was 40%, the temperature was 23-27℃, and the contents of COD, TN and TP in the effluent were collected and detected every day. When the effluent indicators were stable, it was considered that the biofilm formation was completed, the biofilm formation time was recorded, and the removal rates of COD, TN and TP were calculated. The fillers obtained in Examples 7-9 and Comparative Examples 1-5 of the present application were placed in a UV aging test box for UV accelerated aging test, the test conditions were temperature 70℃, humidity 70%, UV intensity 0.68 W / m 2 , aging time 500 h, and after aging, the removal rates of COD, TN and TP were determined according to the above method. The results are recorded in Table 1. Table 1: Test results According to the data in Table 1, the MBBR filler of the present application has faster biofilm formation speed, higher removal rates of COD, TN and TP and stronger anti-aging property. As can be seen from the comparison between Example 9 and Comparative Example 1, when the 2-methoxy-5-formyl pyrimidine used in the preparation process of the modified hydrotalcite is replaced by 5-methoxypyridine-2-aldehyde, the removal rates of COD, TN and TP of the MBBR filler after aging decrease, and the anti-aging property weakens. As can be seen from the comparison between Example 9 and Comparative Example 2, when the 4-nitroimidazole used in the preparation process of the modified hydrotalcite is replaced by N-methyl p-nitroaniline, the removal rates of COD, TN and TP of the MBBR filler after aging decrease, and the anti-aging property weakens. As can be seen from the comparison between Example 9 and Comparative Example 3, when the modified hydrotalcite is replaced by modified hydrotalcite-1 which is obtained by intercalating product g9 into zinc-aluminum hydrotalcite, not only the anti-aging property decreases, but also the compatibility with the matrix weakens, the hydrophilicity of the MBBR filler decreases, the biofilm formation speed decreases, and the removal rates of COD, TN and TP decrease. As can be seen from the comparison between Example 9 and Comparative Example 4, when the triphenylphosphine used in the preparation process of the auxiliary agent is replaced by triethylamine, the biofilm formation speed decreases, and the removal rates of COD, TN and TP decrease. As can be seen from the comparison between Example 9 and Comparative Example 5, when the carbon nanotube used in the preparation process of the auxiliary agent is replaced by halloysite nanotube, the removal rates of COD, TN and TP decrease.

[0031] The above content is only an example and description of the concept of the present application, and those skilled in the art can make various modifications or supplements or use similar ways to replace the described specific embodiments, as long as they do not deviate from the concept of the present application or exceed the scope defined by the present claims, which shall belong to the protection scope of the present application.

Claims

1. A spiral modified MBBR media, characterized in that: The raw materials include the following components in parts by weight: HDPE 100-105 parts, modified hydrotalcite 7-9 parts, auxiliary 4-6 parts, initiator 0.7-0.9 parts, polyvinyl alcohol 1-2 parts, chitin 1-2 parts, gelatin 1.5-3 parts, activated carbon 5-10 parts, zinc stearate 0.5-1 part, EBS dispersant 0.3-0.5 part; The modified hydrotalcite is prepared by the following steps: Step G1, add thiophene aldehyde to acetic anhydride, stir, then add potassium salt, heat and reflux to stir to obtain product g1; add product g1 to DMF, stir, then add dichlorosulfoxide, heat and reflux to stir to obtain product g2; mix nitroimidazole and DMSO, stir, then drop the mixed solution of product g2 in an ice-water bath, heat and stir to obtain product g3; Step G2, mix product g3, DMAC and ethanol solution, stir, then add sodium hydrosulfite, stir to obtain product g4; Mix product g4, epichlorohydrin and DMF, stir, then add tetra-n-butylammonium chloride, heat and stir, then add alkali solution, continue to stir to obtain product g5; Step G3, add aldehyde pyrimidine to acetic anhydride, stir, then add anhydrous potassium carbonate, heat and reflux to stir to obtain product g6; mix product g6, DMAC and triethylamine, stir, then add product g5, heat and stir, then heat and stir to obtain product g7; Step G4, mix sodium carboxybenzenesulfonate, DMSO and ethanol, stir, then add chlorosulfoxide, heat and reflux to stir to obtain product g8; mix product g7, ethyl acetate and DMAC, stir, then add the mixed solution of product g8 in an ice-water bath, heat and reflux to stir to obtain product g9; mix product g9, DMF and ethanol in a protective gas atmosphere, stir, then add aqueous acetic acid and zinc particles, reflux to stir to obtain product g10; Step G5, add zinc chloride and aluminum chloride hexahydrate to deionized water, stir and adjust pH, heat and stir, then age, wash and dry to obtain zinc-aluminum hydrotalcite; add zinc-aluminum hydrotalcite and product g10 to solvent 1, ultrasonic dispersion, stir and adjust pH, heat and stir, wash to neutral and dry to obtain modified hydrotalcite.

2. The spiral modified MBBR media according to claim 1, characterized in that: In step G1, the thiophene aldehyde is 3-thiophene formaldehyde; the nitroimidazole is 4-nitroimidazole.

3. The spiral modified MBBR media according to claim 1, characterized in that: In step G3, the aldehyde pyrimidine is 2-methoxy-5-aldehyde pyrimidine.

4. The spiral modified MBBR media according to claim 1, characterized in that: In step G4, the sodium carboxybenzenesulfonate is 3-sodium carboxybenzenesulfonate.

5. The spiral modified MBBR media according to claim 1, characterized in that: The auxiliary is prepared by the following steps: Step H1, add nano ferric tetroxide to anhydrous ethanol, ultrasonic dispersion, then add hydrogen peroxide solution, heat and stir to obtain pretreated product; Add the pretreated product to ethanol, ultrasonic dispersion, then add silane hydrolysis solution, heat and stir to obtain product h1; Step H2, mix carbon nanotube and acid solution, heat and reflux to stir to obtain product h2; mix product h1, anhydrous ethanol, DMF and triethylamine, stir, then add product h2, heat and stir to obtain product h3; Step H3, mixing triphenylphosphine, brominated alcohol, anhydrous acetonitrile, and passing protective gas, and heating and stirring to obtain product h4; mixing product h4, epichlorohydrin, methanol, DMSO, and adding aqueous sodium hydroxide under stirring, and heating and stirring to obtain product h5; Step H4, mixing product h3, acetonitrile, and methanol under ultrasonic dispersion, adding N,N-dimethylbutylamine and product h5, and heating and stirring under reflux to obtain product h6; mixing product h6, potassium carbonate, DMSO, and acetonitrile under ultrasonic dispersion, adding acryloyl chloride mixture in an ice-water bath, and heating and stirring after completion to obtain the adjuvant.

6. The spiral modified MBBR media according to claim 5, characterized in that: In step H1, the silane hydrolysis solution is obtained by mixing and stirring silane and solvent a, adjusting pH to 5-5.5, and then stirring at room temperature for 1.5-2 h; the silane is 5,6-epoxyhexyltriethoxysilane.

7. The spiral modified MBBR media according to claim 5, characterized in that: In step H3, the brominated alcohol is 5-bromo-1-pentanol.

8. A process for the preparation of the spiral modified MBBR media according to any one of claims 1 to 7, characterized by: The method comprises the following steps: heating and melting HDPE and the adjuvant, then adding an initiator, heating and melting reaction, cooling, adding modified hydrotalcite, polyvinyl alcohol, chitin, gelatin, activated carbon, zinc stearate, and EBS dispersant, heating and melting blending, extruding and granulating, and hot forming into a cylindrical blank by screw extrusion; then cutting the cylindrical blank by using a hard alloy spiral knife, immersing in water after cutting, drying, and then treating by plasma to obtain a spiral modified MBBR filler.

9. The process for preparing a spiral modified MBBR media as claimed in claim 8, wherein: The diameter of the cylindrical blank is 10-25 mm, and the length-diameter ratio is 0.8-1.2; the blade spiral helix angle of the hard alloy spiral knife is 30-60°, the blade width is 2-4 mm, and the blade depth is 1.5-3 mm; the linear velocity is 0.5-1.5 m / s, and the feed is 0.2-0.5 mm / r during the cutting process of the hard alloy spiral knife; and the plasma treatment conditions are power of 300-500 W and time of 90-120 s.

10. Use of the spiral modified MBBR media according to any one of claims 1 to 7, characterized in that: The spiral modified MBBR filler is used for sewage treatment.

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