Iron-carbon modified basalt fiber particle electrode biological carrier as well as preparation method and application thereof

Abstract

The invention discloses an iron-carbon modified basalt fiber particle electrode biological carrier as well as a preparation method and application thereof, the preparation method comprises the following steps: Sa1, grinding and sieving basalt fibers subjected to pretreatment and etching treatment, and soaking the basalt fibers in an iron salt solution for 6-12 hours at the soaking temperature of 50-90 DEG C; sa2, the basalt fibers obtained in the step Sa1 are soaked in a sodium p-toluenesulfonate solution, a pyrrole monomer is added, then a ferric salt solution is added, a reaction is conducted for 12-24 h at the room temperature, and the mass ratio of the basalt fibers to the sodium p-toluenesulfonate to the pyrrole monomer to ferric iron is 5.0: (9.7-10.8): (3.4-4.2): (5.5-6.6); and Sa3, calcining the basalt fiber obtained in the step S2 in stages. The porosity of the iron-carbon modified basalt fiber particle electrode biological carrier is 90-93%, the density of the iron-carbon modified basalt fiber particle electrode biological carrier is 1.03-1.15 g / cm < 3 >, the iron-carbon modified basalt fiber particle electrode biological carrier is easy to suspend due to the high porosity and the low density, microorganisms can be enriched on the surface to grow, enrichment culture of marine anaerobic ammonium oxidation bacteria can be achieved, and therefore the iron-carbon modified basalt fiber particle electrode biological carrier shows excellent denitrification performance on high-salinity nitrogen-containing wastewater.

Description

Technical Field

[0001] The present invention relates to the technical field of microbial wastewater denitrification, and more specifically, to an iron-carbon modified basalt fiber particle electrode biological carrier and its preparation method and application, an anaerobic denitrifying granular sludge reactor and its construction method and application. Background Art

[0002] High-salinity aquaculture wastewater is characterized by high salinity and low carbon-nitrogen ratio. Releasing nitrogen compounds into the marine ecosystem can cause red tides, which will reduce dissolved oxygen and threaten aquatic organisms in seawater. In addition, high salinity is harmful to microorganisms, causing cytoplasmic separation and a sharp increase in osmotic pressure, resulting in the loss of microbial activity. Therefore, developing an efficient biological process to treat saline wastewater is an urgent task.

[0003] Anaerobic ammonium oxidation has broad prospects in the treatment of high-efficiency nitrogen-containing wastewater. As one of the six known genera of anaerobic ammonium-oxidizing bacteria, Candidatus Scalindua belongs to marine anaerobic ammonium-oxidizing bacteria (MAB), which is a very important link in the nitrogen cycle of the marine ecosystem. Compared with anaerobic ammonium-oxidizing bacteria in low-salinity environments, MAB has better salt tolerance and is more suitable for the treatment of saline and nitrogen-containing wastewater. It can maintain stable denitrification performance in a wide range of salt concentrations (5 - 35 g / L sodium chloride), and even has a high denitrification performance at a salinity of 50 g / L. However, anaerobic ammonium-oxidizing bacteria (AnAOB) still have some disadvantages, that is, anaerobic ammonium-oxidizing bacteria (AnAOB) grow slowly, they are easily affected by environmental factors, so they are extremely difficult to culture in practical applications, and the start-up and stable operation of Anammox have become obstacles to its engineering application.

[0004] Anaerobic ammonium oxidation granulation technology is a key strategy to reduce sludge loss and ensure sufficient biomass in the reactor. Granular sludge is favored due to its excellent sedimentation performance, compact structure and high biomass retention ability. Suspended particles can increase the contact efficiency with pollutants in sewage, thereby improving the degradation effect. As a kind of aluminosilicate fiber, basalt fiber has the characteristics of corrosion resistance, good flexibility, high and low temperature resistance and environmental protection, but it has received less attention in the field of high-salinity sewage purification. The main reason is its poor surface conductivity and insufficient bioaffinity, which is not conducive to the rapid adhesion and stable attachment of microorganisms, and the biomass fixation performance is not ideal in sewage treatment applications.

[0005] In summary, there is currently a lack of a modified basalt fiber biological carrier with ideal biomass fixation performance. Summary of the Invention

[0006] Aiming at the problems of weak microbial attachment ability and limited denitrification efficiency caused by the insufficient physical and chemical properties, water dispersibility and conductivity of the existing basalt fibers, the purpose of this application is to improve the biocompatibility and conductivity of basalt fibers, thereby enhancing the treatment efficiency of high-salinity nitrogen-containing wastewater.

[0007] In this application, the basalt fibers are modified with iron and organic polymer carbon materials. On the one hand, the surface charge of the basalt fibers is increased, thereby enhancing the adsorption ability for microorganisms; on the other hand, the conductivity of the basalt fibers is further improved. In addition, a certain reaction can occur between iron and carbon to provide electrons for the carrier electrode to promote the growth and metabolism of microorganisms and increase their denitrification effect.

[0008] In view of this, the purpose of this application is to develop modified basalt fibers with excellent biocompatibility and good conductivity according to the characteristic requirements of biological fillers.

[0009] More specifically, on the first aspect, this application provides a preparation method of an iron-carbon modified basalt fiber particle electrode biological carrier, including the following steps:

[0010] S a 1. After the basalt fibers are pretreated and etched, they are ground and sieved, and then soaked in an iron salt solution for 6 - 12 h, and the soaking temperature is 50 - 90 °C;

[0011] S a 2. The basalt fibers obtained in step S a 1 are soaked in a p-toluenesulfonate solution, pyrrole monomer is added, and then an iron salt solution is added, and the reaction is carried out at room temperature for 12 - 24 h, where the mass ratio of basalt fiber, p-toluenesulfonate, pyrrole monomer, and ferric iron is 5.0:9.7 - 10.8:3.4 - 4.2:5.5 - 6.6;

[0012] S a 3. The basalt fibers obtained in step S2 are calcined in stages, where

[0013] The first stage: The temperature is raised to 180 - 220 °C and kept warm for 25 - 40 min,

[0014] The second stage: The temperature is raised to 350 - 400 °C and kept warm for 80 - 100 min,

[0015] The third stage: The temperature is raised to 510 - 560 °C and kept warm for 100 - 130 min.

[0016] Preferably, the pretreatment in step S a 1 includes: soaking the basalt fibers in an acetone solvent, heating to 38 - 42 °C and reacting for more than 1 h, and / or

[0017] Step Sa The etching treatment in 1 includes: placing basalt fibers in an etching solution and reacting at 20 - 90 °C for 1 - 24 h, and the etching solution includes one or more of hydrochloric acid solution, sulfuric acid solution, hydrogen peroxide solution, and sodium hydroxide solution.

[0018] Preferably, step S a The etching treatment in 1 includes: first placing basalt fibers in hydrochloric acid solution, sulfuric acid solution, or sodium hydroxide solution and reacting at 20 - 90 °C for 2 - 24 h, and then placing them in hydrogen peroxide solution and reacting at 40 - 90 °C for 1 - 12 h.

[0019] Preferably, step S a Before step S a 3, it further includes: washing and purifying the basalt fibers obtained in step S

[0020] In a second aspect, the present application provides an iron - carbon modified basalt fiber particle electrode biological carrier, which is prepared by the preparation method of the above - mentioned iron - carbon modified basalt fiber particle electrode biological carrier.

[0021] Preferably, the porosity of the iron - carbon modified basalt fiber particle electrode biological carrier is 90 - 93%, and the density is 1.03 - 1.15 g / cm 3 .

[0022] In a third aspect, the present application provides a construction method of an anaerobic denitrifying granular sludge reactor, including the following steps:

[0023] S b 1. Inoculate the pretreated marine sediment into the reactor;

[0024] S b 2. Add the iron - carbon modified basalt fiber particle electrode biological carrier prepared by the preparation method of any one of claims 1 - 4 or the iron - carbon modified basalt fiber particle electrode biological carrier as described in any one of claims 5 - 6;

[0025] S b 3. Domestication and cultivation are carried out for 20 - 40 days under the conditions of a temperature of 28 - 32 °C and a stirring speed of 30 - 60 rpm, wherein the influent ammonia nitrogen concentration is 100 - 120 mg / L, the nitrite nitrogen concentration is 100 - 120 mg / L, the sodium chloride concentration is 10 - 35 g / L, the pH is 7.0 - 8.0, and the hydraulic retention time is 10 - 24 hours.

[0026] In a fourth aspect, the present application provides an anaerobic denitrifying granular sludge reactor, which is constructed by the construction method of the above - mentioned anaerobic denitrifying granular sludge reactor.

[0027] Fifth aspect, the present application provides the use of the above-mentioned iron-carbon modified basalt fiber particle electrode biological carrier or the above-mentioned anaerobic denitrifying granular sludge reactor in treating high-salinity nitrogen-containing wastewater, wherein the sodium chloride content in the high-salinity nitrogen-containing wastewater is 10-35 g / L, especially 25-35 g / L.

[0028] Sixth aspect, the present application provides a method for treating high-salinity nitrogen-containing wastewater, including introducing the high-salinity nitrogen-containing wastewater into the above-mentioned anaerobic denitrifying granular sludge reactor, and controlling the temperature in the reactor to be 28-32 °C and the stirring speed to be 30-60 rpm.

[0029] The technical solution of the present application achieves the following technical effects:

[0030] 1. The porosity of the iron-carbon modified basalt fiber particle electrode biological carrier prepared in the present application is 90-93%, and the density is 1.03-1.15 g / cm 3 . The higher porosity and lower density are easy to suspend, which is beneficial to the enrichment and growth of microorganisms on the surface, and can realize the enrichment culture of marine anaerobic ammonium oxidation bacteria.

[0031] 2. In the present application, the basalt fiber is modified by iron and organic polymer carbon materials. On the one hand, the surface charge of the basalt fiber is increased, thereby enhancing the adsorption capacity for microorganisms and facilitating the adsorption and enrichment of microorganisms on its surface; on the other hand, the conductivity of the basalt fiber is further improved.

[0032] 3. The iron-carbon modified basalt fiber particle electrode biological carrier forms a pseudo-galvanic cell effect through the synergistic effect of iron oxide (Fe 2+ / Fe 3+ ) and carbon materials, enhancing the electron transfer ability, thereby promoting anaerobic ammonium oxidation (Anammox) denitrification. The oxidation and reduction of Fe 2+ form an iron redox cycle to continuously transfer electrons. The carbon material serves as a conductive network to integrate the redox activity of iron ions and form Fe-C composite active sites, synergistically improving the electron utilization rate. The high specific surface area and pore structure of the iron-carbon modified basalt fiber particle electrode biological carrier provide attachment sites for Fe 2+ / Fe 3+ and microorganisms, increasing the reaction interface. At the same time, the iron-carbon modified basalt fiber particle electrode biological carrier is corrosion-resistant and can maintain the activity of the Fe-C composite structure for a long time.

[0033] 4. The anaerobic denitrifying granular sludge reactor constructed with the iron-carbon modified basalt fiber particle electrode biological carrier in the present application shows excellent denitrification performance in treating high-salinity nitrogen-containing wastewater (sodium chloride content is 10-35 g / L, especially 25-35 g / L), with the ammonia nitrogen removal rate exceeding 93% and the nitrite nitrogen removal rate exceeding 91%.

[0034] The concept, specific structure and technical effects of this application will be further described below in conjunction with the accompanying drawings to fully understand the purpose, features and effects of this application. Description of the Drawings

[0035] Figure 1 It is the SEM image of basalt fiber after pretreatment and etching treatment in Example 1 of this application.

[0036] Figure 2 It is the SEM image of basalt fiber before calcination after being modified by iron and organic polymer carbon material in Example 1 of this application.

[0037] Figure 3 It is the SEM image of the iron-carbon modified basalt fiber particle electrode biological carrier after calcination in Example 1 of this application.

[0038] Figure 4 It is the EDS elemental analysis chart of the finally obtained iron-carbon modified basalt fiber particle electrode biological carrier in Example 1 of this application.

[0039] Figure 5 It is another EDS elemental analysis chart of the finally obtained iron-carbon modified basalt fiber particle electrode biological carrier in Example 1 of this application.

[0040] Figure 6 It is the C element XPS chart of the iron-carbon modified basalt fiber particle electrode biological carrier in Example 1 of this application.

[0041] Figure 7 It is the Fe element XPS chart of the iron-carbon modified basalt fiber particle electrode biological carrier in Example 1 of this application.

[0042] Figure 8 It is the schematic diagram of the anaerobic denitrifying granular sludge reactor of this application.

[0043] Figure 9 It is the statistical chart of the change of NH4 + -N and NO2 - -N inlet and outlet concentrations in nitrogen-containing wastewater with different sodium chloride concentrations in Example 9. Detailed Implementation Modes

[0044] The implementation modes of this application will be described below through specific examples. Those skilled in the art can easily understand the other advantages and effects of this application from the content disclosed in this specification. This application can also be implemented or applied through other different specific implementation modes. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, without conflict, the following examples and the features in the examples can be combined with each other.

[0045] For the purpose of illustration, some exemplary embodiments of the present application are described. It should be understood that the present application can be implemented in other ways not specifically shown in the drawings.

[0046] In a first aspect, the present application provides a method for preparing an iron-carbon modified basalt fiber particle electrode biological carrier, comprising the following steps: S a 1. Grind and screen the pretreated and etched basalt fibers, and then perform iron modification; S a 2. Modify the basalt fibers obtained in step S a 1 with an organic polymer carbon material; S a 3. Calcinate in stages to obtain the final product. Each step is introduced in detail below.

[0047] Regarding the iron modification of basalt fibers

[0048] Before the iron modification of basalt fibers, the basalt fibers are pretreated and etched. The purpose of the pretreatment is to remove the original binder and impurities on the surface of the basalt fibers. Specifically, the pretreatment method is to soak the basalt fibers in an acetone solvent and heat to 38 - 42 °C for more than 1 h. It should be understood that other pretreatment methods can also be used in the present application. For example, acetone can be replaced with other solvents (such as ethanol), and the temperature and reaction time can be selected according to the selected solvent and other actual situations, as long as the purpose of removing the original binder and impurities on the surface of the basalt fibers can be achieved. Drying is preferably performed after the pretreatment. The drying temperature is not limited in the present application, as long as there is no cleaning solvent attached to the surface of the basalt fibers.

[0049] The etching treatment step is carried out after the pretreatment. The purpose of the etching treatment is to increase the surface roughness of the basalt fibers and improve the subsequent loading of the modified materials. Specifically, the etching treatment method is to place the pretreated basalt fibers in an etching solution and react at 20 - 90 °C for 1 - 24 h. The etching solution includes one or more of hydrochloric acid solution, sulfuric acid solution, hydrogen peroxide solution, and sodium hydroxide solution. The concentration of the etching solution is not limited in the present application, as long as the surface roughness of the basalt fibers can be increased. When the concentration of the etching solution is low, the etching time can be appropriately increased. When the concentration of the etching solution is high, the etching time can be appropriately reduced. For example, the concentration of the etching solution can be selected as 1 M, 1.5 M, etc.

[0050] In a specific embodiment, the etching treatment includes first placing the pretreated basalt fibers in hydrochloric acid solution, sulfuric acid solution, or sodium hydroxide solution and reacting at 20 - 90 °C for 2 - 24 h, and then placing them in hydrogen peroxide solution and reacting at 40 - 90 °C for 1 - 12 h. Treating the basalt fibers with hydrochloric acid solution, sulfuric acid solution, or sodium hydroxide solution can increase their surface defects, and then soaking them in hydrogen peroxide can increase the Si - O groups on the surface of the basalt fibers, enabling subsequent organic polymer carbon materials to be loaded on their surface. The subsequent high - temperature calcination to form a porous and loose structure is beneficial to the enrichment and growth of microorganisms.

[0051] It should be understood that other etching treatment methods can also be used in this application. For example, other etching solutions can be used for substitution, and the temperature and reaction time can be selected according to the selected solution and other actual situations, as long as the purpose of increasing the surface roughness of the basalt fibers can be achieved. After the etching treatment, washing and drying are preferably carried out to remove the etching solution. The drying temperature is not limited in this application, as long as there is no cleaning solution attached to the surface of the basalt fibers.

[0052] Before iron modification, the pretreated and etched basalt fibers are ground and sieved. The purpose is to make the subsequent loading of the modified material more sufficient. The grinding sieves can be 140 mesh, 170 mesh, 200 mesh, 230 mesh, etc. The selection of the sieve holes is not limited in this application.

[0053] The method of iron modification includes soaking the ground and sieved basalt fibers in iron salt solution for 6 - 12 h for physical sedimentation to load iron elements. The soaking temperature is 50 - 90 °C. In this application, the iron salt solution is ferric chloride solution, and its concentration is not limited, as long as it can submerge the basalt fibers and achieve the loading of iron elements. Preferably, the concentration is above 1 M. After the reaction is completed, it is washed with deionized water and dried to obtain iron - modified basalt fibers Fe - MBF.

[0054] Regarding the modification of basalt fibers with organic polymer carbon materials

[0055] The method for modifying basalt fibers with organic polymer carbon materials is as follows: Soak the above - prepared iron - modified basalt fibers Fe - MBF in sodium p - toluenesulfonate solution, add pyrrole monomer, and then add iron salt solution, and react at room temperature for 12 - 24 h to prepare basalt particles modified with iron - organic polymer carbon materials through chemical oxidative polymerization reaction. In this step, the mass ratio of basalt fibers, sodium p - toluenesulfonate, pyrrole monomer, and ferric iron is 5.0:9.7 - 10.8:3.4 - 4.2:5.5 - 6.6.

[0056] Regarding the sodium p-toluenesulfonate solution, its concentration is not limited in this application. As long as the mass ratio of basalt fiber, sodium p-toluenesulfonate, pyrrole monomer, and ferric iron is 5.0:9.7 - 10.8:3.4 - 4.2:5.5 - 6.6, and it can submerge the basalt fiber. Regarding the iron salt solution, it is an aqueous solution prepared from FeCl3·6H2O, and its concentration is not limited in this application. As long as the mass ratio of basalt fiber, sodium p-toluenesulfonate, pyrrole monomer, and ferric iron is 5.0:9.7 - 10.8:3.4 - 4.2:5.5 - 6.6.

[0057] After the reaction is completed, the basalt fiber is washed and purified with deionized water and ethanol to wash away impurities and the unloaded loading materials that are not successfully loaded. Then it is placed in an oven and dried at 60 - 70 °C.

[0058] Regarding staged calcination

[0059] The basalt fiber modified by iron and organic polymer carbon material is then subjected to a calcination step. The calcination atmosphere is nitrogen, and the calcination adopts a staged calcination method:

[0060] The first stage: low-temperature pre-calcination (from room temperature to 180 - 220 °C, heating rate 4 - 6 °C / min, holding time 25 - 40 min) to remove moisture, volatile organic compounds or other impurities in the raw materials and avoid side reactions in the medium- and high-temperature stages;

[0061] The second stage: medium-temperature reaction (raising the temperature to 350 - 400 °C, heating rate 2 - 4 °C / min, holding for 80 - 100 min) to promote the preliminary reaction between the metal and the carbon source, form precursors or intermediate products, and at the same time avoid the reaction getting out of control due to too high temperature;

[0062] The third stage: high-temperature carbonization (raising the temperature to 510 - 560 °C, heating rate 1 - 3 °C / min, holding for 100 - 130 min) to complete the carbonization reaction at this temperature, generate the target carbide, and optimize the crystal structure and product performance.

[0063] In this application, the basalt fiber is modified by iron and organic polymer carbon material. On the one hand, it increases the surface charge of the basalt fiber, thereby enhancing the adsorption capacity for microorganisms and facilitating the adsorption and enrichment of microorganisms on its surface. On the other hand, it further improves the conductivity of the basalt fiber.

[0064] In the second aspect, this application provides an iron-carbon modified basalt fiber particle electrode biological carrier, which is prepared by the above-mentioned preparation method of the iron-carbon modified basalt fiber particle electrode biological carrier. The porosity of the iron-carbon modified basalt fiber particle electrode biological carrier is 90 - 93%, and the density is 1.03 - 1.15 g / cm 3, Higher porosity and lower density are conducive to suspension, which is beneficial for the enrichment and growth of microorganisms on the surface, enabling the enrichment culture of marine anaerobic ammonium-oxidizing bacteria. Among them, iron, as a basic substrate and potential energy source, plays a crucial role in the metabolism of anaerobic ammonium-oxidizing bacteria. In the presence of insoluble electron acceptors or electrodes, pre-enriched anaerobic ammonium-oxidizing bacteria can achieve nitrite-free electroactive oxidation of ammonia through extracellular electron transfer, while conductive carriers promote the biofilm formation and granulation process of anaerobic ammonium-oxidizing bacteria. Polypyrrole (PPy) has advantages such as good biocompatibility, excellent electrical conductivity, high thermal conductivity, environmental stability, non-toxicity, high porosity, easy synthesis, and low cost. In addition, PPy can reversibly transform between charged and neutral forms, which is more conducive to the adsorption and enrichment of microorganisms on its surface.

[0065] The iron-carbon modified basalt fiber particle electrode biological carrier forms a kind of primary battery effect through the synergistic action of iron oxides (Fe 2+ / Fe 3+ ) and carbon materials, enhancing the electron transfer ability, thereby promoting anaerobic ammonium oxidation (Anammox) denitrification.

[0066] Oxidation of Fe 2+ (electron release):

[0067] Fe 2+ →Fe 3+ +e - In an anaerobic environment, Fe 2+ can be oxidized to Fe 3+ and release electrons, which can be directly utilized by Anammox bacteria or denitrifying bacteria to drive the denitrification reaction (such as NO2 - reduction);

[0068] Reduction of Fe 3+ (electron acceptance):

[0069] Fe 3+ +e - →Fe 2+ , Fe 3+ can accept electrons from organic matter or microbial metabolism and be reduced to Fe 2+ , forming an iron redox cycle to continuously transfer electrons.

[0070] As a conductive network, carbon materials integrate the redox activity of iron ions to form Fe-C composite active sites, synergistically improving the electron utilization rate. The high specific surface area and pore structure of the iron-carbon modified basalt fiber particle electrode biological carrier provide a favorable environment for Fe 2+ / Fe 3+Provide attachment sites for microorganisms, increase the reaction interface, and at the same time, the iron-carbon modified basalt fiber particle electrode biological carrier is corrosion-resistant and can maintain the activity of the Fe-C composite structure for a long time.

[0071] In a third aspect, the present application provides a method for constructing an anaerobic denitrifying granular sludge reactor. The key to the construction of this reactor lies in the domestication and cultivation of marine sludge. First, an anaerobic microbial denitrification reactor for accommodating marine sludge needs to be constructed. This reactor has good sealing performance, is equipped with a reaction zone, a sedimentation zone, a stirring device and a microbial interception device, and also has supporting inlet and outlet facilities. The reactor is immersed in an opaque incubator, and a temperature control heating rod is installed in the incubator to maintain the water temperature at 28°C - 32°C.

[0072] Extract sludge from marine sediment, wash the marine sludge with a washing solution 3 - 5 times, each time for 10 - 15 minutes. After washing, let it stand, pour out the impurities washed out to obtain the required marine sludge. Subsequently, inoculate the marine sludge into the above-mentioned anaerobic microbial denitrification reactor whose sealing performance has been tested (maintaining the MLVSS at 3000 - 4000 mg / L), and at the same time add the above-mentioned iron-carbon modified basalt fiber particle electrode biological carrier and stir to promote the enrichment of microorganisms on the carrier. For every 300 ml of marine sludge inoculated, add 4 g - 6 g of the iron-carbon modified basalt fiber particle electrode biological carrier. During the cultivation of marine sludge, maintain the stirring speed at 30 - 60 rpm to make the iron-carbon modified basalt fiber particle electrode biological carrier fully contact with the marine sludge. And because the iron-carbon modified basalt fiber particle electrode biological carrier has a high porosity and a low density, it suspends in the reactor, which is beneficial to the enrichment and growth of microorganisms on the surface, and can realize the enrichment cultivation of marine anaerobic ammonium-oxidizing bacteria.

[0073] Configure artificial high-salinity nitrogen-containing wastewater: The concentration of sodium chloride is 10 - 35 g / L. Potassium dihydrogen phosphate, calcium chloride, potassium bicarbonate, magnesium sulfate, trace element I, and trace element II are added sequentially to the artificial high-salinity nitrogen-containing wastewater. The ammonia nitrogen and nitrite nitrogen contents at the initial inlet are 100 - 120 mg / L respectively. Control the pH of the artificial high-salinity nitrogen-containing wastewater to be 7.0 - 8.0. Among them, 0.01 - 0.05 mg of potassium dihydrogen phosphate, 0.1 - 0.5 mg of calcium chloride, 0.5 - 5 mg of potassium bicarbonate, 0.1 - 0.5 mg of magnesium sulfate, 0.1 - 2 mL of trace element I, and 0.1 - 2 mL of trace element II are added per liter of the artificial high-salinity nitrogen-containing wastewater. The composition and content of trace element I are: ethylenediaminetetraacetic acid 1 - 10 g / L, ferrous sulfate 1 - 10 g / L; the composition and content of trace element II are: ethylenediaminetetraacetic acid 10 - 20 g / L, boric acid 0.01 - 0.05 g / L, manganese chloride 0.5 - 2 g / L, copper sulfate 0.1 - 0.5 g / L, zinc sulfate 0.1 - 1 g / L, nickel chloride 0.1 - 0.5 g / L, cobalt chloride 0.1 - 0.5 g / L, sodium selenate 0.1 - 0.5 g / L. The configured artificial high-salinity nitrogen-containing wastewater is introduced into the reactor. In some of these embodiments, a peristaltic pump is used as the water inlet device to supply water to the above anaerobic microbial denitrification reactor. During the continuous flow operation of the reactor, it is calculated according to the effective volume of the reactor and the inlet water flow rate to keep the hydraulic retention time (HRT) maintained at a set time (for example, 10 - 24 hours, specifically selected according to the actual situation).

[0074] The dissolved oxygen concentration of the influent is controlled below 0.5 mg / L by aerating nitrogen to provide a suitable living environment for anaerobic ammonium oxidation bacteria.

[0075] The cultivation time of marine sludge can be selected according to the actual situation as long as it can meet the requirement that the MLVSS of the marine sludge does not decrease significantly and the total nitrogen removal rate of the marine sludge for the influent reaches more than 70%. For example, it can be domesticated and cultivated for 20 - 40 days, etc. The number of days in the following embodiments does not constitute a limitation of this application.

[0076] Fourthly, this application provides an anaerobic denitrifying granular sludge reactor, which is constructed by the above-mentioned construction method of the anaerobic denitrifying granular sludge reactor. The anaerobic denitrifying granular sludge reactor constructed using the iron-carbon modified basalt fiber particle electrode biological carrier shows excellent denitrification performance in treating high-salinity nitrogen-containing wastewater (the sodium chloride content is 10 - 35 g / L, especially 25 - 35 g / L), with the ammonia nitrogen removal rate exceeding 93% and the nitrite nitrogen removal rate exceeding 91%.

[0077] Fifth aspect, the present application provides the use of the above-mentioned iron-carbon modified basalt fiber particle electrode biological carrier or the above-mentioned anaerobic denitrifying granular sludge reactor in treating high-salinity nitrogen-containing wastewater, wherein the sodium chloride content in the high-salinity nitrogen-containing wastewater is 10-35 g / L, especially 25-35 g / L.

[0078] Sixth aspect, the present application provides a method for treating high-salinity nitrogen-containing wastewater, including introducing the high-salinity nitrogen-containing wastewater into the above-mentioned anaerobic denitrifying granular sludge reactor, and controlling the temperature in the reactor to be 28-32 °C and the stirring speed to be 30-60 rpm. The sodium chloride concentration in the high-salinity nitrogen-containing wastewater is 10-35 g / L, especially 25-35 g / L. The inorganic nitrogen in the high-salinity nitrogen-containing wastewater is a mixture of ammonia nitrogen and nitrite nitrogen, a mixture of ammonia nitrogen and nitrate nitrogen, or a mixture of ammonia nitrogen, nitrite nitrogen and nitrate nitrogen.

[0079] In some of these embodiments, the high-salinity nitrogen-containing wastewater is fed continuously, and the hydraulic retention time ≥ 10 h.

[0080] Example 1 Preparation of Iron-Carbon Modified Basalt Fiber Particle Electrode Biological Carrier I

[0081] 1. Iron modification of basalt fiber

[0082] Soak 10 g of basalt fiber in 0.5 L of acetone solvent, heat it in a water bath to 40 °C, react for 3 h and then dry it. Subsequently, place it in 0.5 L of sodium hydroxide solution with a concentration of 1 M and react at 40 °C for 12 h. After the reaction is completed, wash, dry and grind it through a sieve (200 mesh). The scanning electron microscope image of the sieved basalt fiber is as shown in Figure 1 Weigh 5 g of the ground and sieved basalt fiber powder, soak it in 0.5 L of iron salt solution with a concentration of 1 M and react at 60 °C for 8 h. After the reaction is completed, wash it with deionized water and dry it to obtain iron-modified basalt fiber Fe-MBF for standby.

[0083] 2. Organic polymer carbon material modification of basalt fiber

[0084] Weigh 9.71 g of sodium p-toluenesulfonate and add it to 0.5 L of deionized water, stir to dissolve it fully to obtain a sodium p-toluenesulfonate solution. Soak 5 g of Fe-MBF in the prepared sodium p-toluenesulfonate solution, slowly drop 3.5 g of pyrrole monomer, stir for 5 min and then drop the prepared iron chloride solution (the preparation method is to weigh 27 g of FeCl3·6H2O and add it to 0.1 L of deionized water, stir to dissolve it fully). Stir at room temperature for 20 h to prepare organic polymer carbon material-modified basalt particles through chemical oxidative polymerization reaction. After the reaction is completed, wash and purify the modified basalt fiber with deionized water and ethanol, and place it in an oven at 70 °C for drying for standby. The scanning electron microscope image of the basalt fiber obtained in this step is as shown inFigure 2 as shown

[0085] 3. Calcination in stages

[0086] The basalt fibers prepared above are placed in a tubular furnace for calcination in stages, and the calcination atmosphere is nitrogen:

[0087] The first stage: low-temperature pre-calcination, heating up to 200 °C at a heating rate of 5 °C / min and holding for 30 minutes;

[0088] The second stage: medium-temperature reaction, heating up to 400 °C at a heating rate of 3 °C / min and holding for 90 min;

[0089] The third stage: high-temperature carbonization, heating up to 550 °C at a heating rate of 2 °C / min and holding for 120 minutes to complete the carbonization reaction, generating the target carbide iron-carbon modified basalt fiber particle electrode biological carrier. Figure 3 The scanning electron microscope image of the iron-carbon modified basalt fiber particle electrode biological carrier is shown. Figure 4 and Figure 5 The EDS elemental analysis diagram of the iron-carbon modified basalt fiber particle electrode biological carrier is shown. It can be seen that the surface is loaded with uniform C elements and Fe elements, and the Si element is wrapped inside by the C element after the carbonization of polypyrrole. The following table also shows the distribution of each element. Figure 6 The C element XPS diagram of the iron-carbon modified basalt fiber particle electrode biological carrier is shown, indicating that the C element is successfully loaded on the surface of the iron-carbon modified basalt fiber particle electrode biological carrier. Figure 7 The Fe element XPS diagram of the iron-carbon modified basalt fiber particle electrode biological carrier is shown, indicating that the Fe element is successfully loaded on the surface of the iron-carbon modified basalt fiber particle electrode biological carrier. As can be seen from the figure, the peaks at 728.0 eV and 711.2 eV are related to Fe 3+ and the binding energies of the Fe 2+ peaks are 724.1 eV and 709.5 eV respectively, and the satellite peak at 722.6 eV corresponds to Fe 3+ , and the satellite peak at 715.4 eV corresponds to Fe 2+ .

[0090]

[0091] Example 2 Preparation of the iron-carbon modified basalt fiber particle electrode biological carrier II

[0092] 1. Iron modification of basalt fibers

[0093] Soak 10 g of basalt fibers in 0.5 L of acetone solvent, heat in a water bath to 38 °C, react for 5 h and then dry. Subsequently, place them in 0.5 L of a hydrochloric acid solution with a concentration of 1 M and react at 20 °C for 24 h. After the reaction is completed, wash, dry and grind through a sieve (170 mesh). Weigh 5 g of the ground and sieved basalt fiber powder, soak it in 0.5 L of a ferric salt solution with a concentration of 2 M and react at 50 °C for 12 h. After the reaction is completed, wash with deionized water and dry to obtain iron-modified basalt fibers Fe-MBF for standby.

[0094] 2. Modification of basalt fibers with organic polymer carbon materials

[0095] Weigh 9.71 g of sodium p-toluenesulfonate and add it to 0.5 L of deionized water, stir to dissolve it fully to obtain a sodium p-toluenesulfonate solution. Immerse 5 g of Fe-MBF in the prepared sodium p-toluenesulfonate solution, slowly drop in 3.4 g of pyrrole monomer, stir for 5 min and then drop in the prepared ferric chloride solution (the preparation method is to weigh 26.5 g of FeCl3·6H2O and add it to 0.1 L of deionized water, stir to dissolve it fully). Stir at room temperature for 12 h to prepare organic polymer carbon material-modified basalt particles through chemical oxidation polymerization reaction. After the reaction is completed, wash and purify the modified basalt fibers with deionized water and ethanol, and place them in an oven at 60 °C for drying for standby.

[0096] 3. Staged calcination

[0097] Place the basalt fibers prepared above in a tube furnace for staged calcination, and the calcination atmosphere is nitrogen:

[0098] The first stage: Low-temperature pre-calcination, heat up to 180 °C, heating rate 4 °C / min, keep warm for 25 minutes;

[0099] The second stage: Medium-temperature reaction, heat up to 350 °C, heating rate 2 °C / min, keep warm for 80 min;

[0100] The third stage: High-temperature carbonization, heat up to 510 °C, heating rate 1 °C / min, keep warm for 100 minutes to complete the carbonization reaction and generate the target carbide. The relevant test results in this example are similar to those in Example 1 and are omitted here.

[0101] Example 3 Preparation of iron-carbon modified basalt fiber particle electrode biological carrier Three

[0102] 1. Iron modification of basalt fibers

[0103] Soak 10 g of basalt fibers in 0.5 L of acetone solvent, heat them in a water bath to 42 °C, react for 1 h and then dry. Subsequently, place them in 0.5 L of sulfuric acid solution with a concentration of 1 M and react at 90 °C for 1 h. After the reaction is completed, wash, dry and grind them through a sieve (230 mesh). Weigh 5 g of the ground and sieved basalt fiber powder, soak it in 0.5 L of iron salt solution with a concentration of 1 M and react at 90 °C for 6 h. After the reaction is completed, wash it with deionized water and dry to obtain iron-modified basalt fibers Fe-MBF for standby.

[0104] 2. Modification of basalt fibers with organic polymer carbon materials

[0105] Weigh 10.8 g of sodium p-toluenesulfonate and add it to 0.5 L of deionized water, stir to dissolve it completely to obtain a sodium p-toluenesulfonate solution. Immerse 5 g of Fe-MBF in the prepared sodium p-toluenesulfonate solution, slowly drop 4.2 g of pyrrole monomer, stir for 5 min and then drop the prepared iron chloride solution (the preparation method is to weigh 31.3 g of FeCl3·6H2O and add it to 0.1 L of deionized water, stir to dissolve it completely). Stir at room temperature for 24 h to prepare organic polymer carbon material-modified basalt particles through chemical oxidation polymerization reaction. After the reaction is completed, wash and purify the modified basalt fibers with deionized water and ethanol, and place them in an oven at 65 °C for drying for standby.

[0106] 3. Calcination in stages

[0107] Place the above-prepared basalt fibers in a tube furnace for calcination in stages, and the calcination atmosphere is nitrogen:

[0108] The first stage: low-temperature pre-calcination, heat up to 220 °C at a heating rate of 6 °C / min, and keep the temperature for 40 minutes;

[0109] The second stage: medium-temperature reaction, heat up to 400 °C at a heating rate of 4 °C / min, and keep the temperature for 100 min;

[0110] The third stage: high-temperature carbonization, heat up to 560 °C at a heating rate of 3 °C / min, and keep the temperature for 130 minutes to complete the carbonization reaction to generate the target carbide. The relevant detection diagrams in this example are similar to those in Example 1 and are omitted here.

[0111] Example 4 Preparation of iron-carbon modified basalt fiber particle electrode biological carrier Four

[0112] 1. Iron modification of basalt fibers

[0113] Soak 10 g of basalt fibers in 0.5 L of acetone solvent, heat them in a water bath to 40 °C, react for 4 h and then dry. Subsequently, place them in 0.5 L of a sodium hydroxide solution with a concentration of 1 M and react at 40 °C for 12 h. Then, place them in 0.5 L of a hydrogen peroxide solution with a concentration of 1 M and react at 50 °C for 6 h. After the reaction is completed, wash, dry and grind and sieve (200 mesh). Weigh 5 g of the ground and sieved basalt fiber powder, soak it in 0.5 L of a ferric salt solution with a concentration of 1 M and react at 70 °C for 4 h. After the reaction is completed, wash with deionized water and dry to obtain iron-modified basalt fibers Fe-MBF for standby.

[0114] 2. Modification of basalt fibers with organic polymer carbon materials

[0115] Weigh 10.2 g of sodium p-toluenesulfonate and add it to 0.5 L of deionized water, stir to dissolve it fully to obtain a sodium p-toluenesulfonate solution. Soak 5 g of Fe-MBF in the prepared sodium p-toluenesulfonate solution, slowly drop 4.0 g of pyrrole monomer, stir for 5 min and then drop the prepared ferric chloride solution (the preparation method is to weigh 28.9 g of FeCl3·6H2O and add it to 0.1 L of deionized water, stir to dissolve it fully). Stir at room temperature for 22 h to prepare organically polymer-carbon-material-modified basalt particles through chemical oxidative polymerization reaction. After the reaction is completed, wash and purify the modified basalt fibers with deionized water and ethanol, and place them in an oven at 70 °C for drying for standby.

[0116] 3. Staged calcination

[0117] Place the above-prepared basalt fibers in a tube furnace for staged calcination, and the calcination atmosphere is nitrogen:

[0118] The first stage: Low-temperature pre-calcination, heat up to 200 °C at a heating rate of 5 °C / min, and keep the temperature for 30 minutes;

[0119] The second stage: Medium-temperature reaction, heat up to 400 °C at a heating rate of 3 °C / min, and keep the temperature for 90 minutes;

[0120] The third stage: High-temperature carbonization, heat up to 550 °C at a heating rate of 2 °C / min, and keep the temperature for 120 minutes to complete the carbonization reaction to generate the target carbide. The relevant detection diagrams in this example are similar to those in Example 1 and are omitted here.

[0121] Example 5 Construction of an anaerobic denitrifying granular sludge reactor I

[0122] Extract sludge from marine sediment, wash the marine sludge with the washing solution 3 - 5 times, 10 - 15 minutes each time. After washing, let it stand, and pour out the impurities washed out to obtain the required marine sludge. Refer to Figure 8As shown in the schematic diagram, 0.3 L of marine sludge was inoculated into an anaerobic microbial denitrification reactor whose sealing performance had been tested, maintaining the MLVSS at 4,000 mg / L, and at the same time, 5 g of the iron-carbon modified basalt fiber particle electrode biological carrier prepared in Example 1 was added. The entire reactor was immersed in an opaque insulated box with a lid, which was equipped with a temperature-controlled heating rod, a pH detection system, and a speed controller, so that during the entire cultivation process, the water temperature inside the reactor was maintained at 30 ± 1 °C, the stirring speed was maintained at 30 rpm, and the pH value was maintained at 7.

[0123] Prepare simulated high-salinity nitrogen-containing wastewater according to the following formula. After the simulated high-salinity nitrogen-containing wastewater for influent was prepared, it was aerated with high-purity nitrogen for more than 30 minutes to remove the dissolved oxygen (<0.3 mg / L) in the solution. Subsequently, a peristaltic pump was used to continuously feed water into the reactor, with a hydraulic retention time of 24 h and a stable operation for 20 days, allowing the inoculated marine sludge to adapt to the new environment in the reactor and achieving the enrichment culture of marine anaerobic ammonium-oxidizing bacteria. At this time, the MLVSS of the denitrifying granular sludge did not decrease significantly, and the total nitrogen removal rate of the denitrifying granular sludge for the influent reached more than 70%. Among them, the composition of the simulated high-salinity nitrogen-containing wastewater: NH4 + -N 100 mg / L (prepared with NH4Cl), NO2 - -N 100 mg / L (prepared with NaNO2), NaCl 10 g / L. Among them, 0.01 mg of potassium dihydrogen phosphate, 0.1 mg of calcium chloride, 0.5 mg of potassium bicarbonate, 0.1 mg of magnesium sulfate, 0.1 mL of trace element I, and 0.1 mL of trace element II were added to each liter of simulated high-salinity nitrogen-containing wastewater. The composition and content of trace element I were: ethylenediaminetetraacetic acid 1 g / L, ferrous sulfate 1 g / L; the composition and content of trace element II were: ethylenediaminetetraacetic acid 10 g / L, boric acid 0.01 g / L, manganese chloride 0.5 g / L, copper sulfate 0.1 g / L, zinc sulfate 0.1 g / L, nickel chloride 0.1 g / L, cobalt chloride 0.1 g / L, sodium selenate 0.1 g / L. All the reagents used in this example were purchased from Shanghai Titan Technology Co., Ltd. and Shanghai Yuanye Biotechnology Co., Ltd. During the entire cultivation process, the DO was strictly controlled, and the effluent of the reactor was in-situ detected, with DO < 0.5 mg / L.

[0124] At this stage, the marine sludge in the reactor changed from the initial black mud-like state to a brown flocculent state, and then from a brown flocculent state to a dark red flocculent sludge, and finally from a dark red flocculent sludge to a brick-red large granular state, possessing the typical characteristics of marine anaerobic ammonium-oxidizing bacteria, and achieving the enrichment culture of marine anaerobic ammonium-oxidizing bacteria.

[0125] Construction of the anaerobic denitrifying granular sludge reactor in Example 6 II

[0126] Extract sludge from marine sediment, and wash the marine sludge with the eluent 3 - 5 times, 10 - 15 minutes each time. After washing, let it stand, and pour out the impurities washed out to obtain the required marine sludge. Refer to Figure 8 As shown in the schematic diagram, inoculate 0.3 L of marine sludge into an anaerobic microbial denitrification reactor whose sealing performance has been tested, maintain the MLVSS at 3000 mg / L, and at the same time add 6 g of the iron - carbon modified basalt fiber particle electrode biological carrier prepared in Example 1. The entire reactor is immersed in an opaque insulated box with a lid, which is equipped with a temperature - controllable heating rod, a pH detection system, and a speed controller, so that during the entire cultivation process, the water temperature inside the reactor is maintained at 31 ± 1 °C, the stirring speed is maintained at 60 rpm, and the pH value is maintained at 8.

[0127] Configure simulated high - salinity nitrogen - containing wastewater according to the following formula. After the simulated high - salinity nitrogen - containing wastewater for influent is configured, aerate it with high - purity nitrogen for more than 30 minutes to remove the dissolved oxygen (<0.3 mg / L) in the solution. Then, use a peristaltic pump to continuously feed water into the reactor, with a hydraulic retention time of 12 h, and stably operate for 40 days to allow the inoculated marine sludge to adapt to the new environment in the reactor and achieve the enrichment cultivation of marine anaerobic ammonium - oxidizing bacteria. At this time, the MLVSS of the denitrifying granular sludge does not decrease significantly and the total nitrogen removal rate of the denitrifying granular sludge for the influent reaches more than 70%. Among them, the components of the simulated high - salinity nitrogen - containing wastewater are: NH4 + -N 120 mg / L (prepared with NH4Cl), NO2 - -N 120 mg / L (prepared with NaNO2), NaCl 35 g / L. Among them, 0.05 mg of potassium dihydrogen phosphate, 0.5 mg of calcium chloride, 5 mg of potassium bicarbonate, 0.5 mg of magnesium sulfate, 2 mL of trace element I, and 2 mL of trace element II are added to each liter of simulated high - salinity nitrogen - containing wastewater. The components and contents of trace element I are: ethylenediaminetetraacetic acid 10 g / L, ferrous sulfate 10 g / L; the components and contents of trace element II are: ethylenediaminetetraacetic acid 20 g / L, boric acid 0.05 g / L, manganese chloride 2 g / L, copper sulfate 0.5 g / L, zinc sulfate 1 g / L, nickel chloride 0.5 g / L, cobalt chloride 0.5 g / L, sodium selenate 0.5 g / L. All the reagents used in this example are purchased from Shanghai Titan Scientific Co., Ltd. and Shanghai Yuanye Bio - Technology Co., Ltd. During the entire cultivation process, strictly control the DO, and conduct in - situ detection of the reactor effluent, with DO < 0.5 mg / L.

[0128] At this stage, the marine sludge in the reactor changes from the initial black mud - like state to brown flocculent, then from brown flocculent to dark red flocculent sludge, and finally from dark red flocculent sludge to brick - red large granular, with the typical characteristics of marine anaerobic ammonium - oxidizing bacteria, achieving the enrichment cultivation of marine anaerobic ammonium - oxidizing bacteria.

[0129] Example 7 Treatment of Simulated Wastewater with High Salinity and Nitrogen - Part 1

[0130] Introduce simulated wastewater into the anaerobic microbial denitrification reactor of Example 5 as an example for denitrification treatment.

[0131] The reactor operates continuously with a hydraulic retention time of 24 h, and the water temperature is maintained at 31°C ± 1°C. The simulated wastewater enters the reactor through a peristaltic pump from the inlet pipe. In the reactor, marine anaerobic ammonium - oxidizing bacteria use ammonia nitrogen as the electron donor and nitrite nitrogen as the electron acceptor to convert the two into nitrogen gas and discharge it from the reactor, achieving efficient denitrification treatment of the simulated wastewater with high salinity and nitrogen.

[0132] Parameters of the simulated wastewater: NH4 + -N 100 mg / L, NO2 - -N 100 mg / L, NaCl 10 g / L. Among them, 0.01 mg of potassium dihydrogen phosphate, 0.1 mg of calcium chloride, 0.5 mg of potassium bicarbonate, 0.1 mg of magnesium sulfate, 0.1 mL of trace element I, and 0.1 mL of trace element II are added per liter of the simulated wastewater. The composition and content of trace element I are: ethylenediaminetetraacetic acid 1 g / L, ferrous sulfate 1 g / L; the composition and content of trace element II are: ethylenediaminetetraacetic acid 10 g / L, boric acid 0.01 g / L, manganese chloride 0.5 g / L, copper sulfate 0.1 g / L, zinc sulfate 0.1 g / L, nickel chloride 0.1 g / L, cobalt chloride 0.1 g / L, sodium selenate 0.1 g / L. All the chemicals used in this example are purchased from Shanghai Titan Scientific Co., Ltd. and Shanghai Yuanye Biotechnology Co., Ltd. After the inlet solution is prepared, it is aerated with high - purity nitrogen for more than 30 minutes to remove the dissolved oxygen (<0.3 mg / L) in the solution.

[0133] After detection, within 0 - 30 days, the removal effects of ammonia nitrogen and nitrite nitrogen in the simulated wastewater by this application are significant. The ammonia nitrogen removal rate exceeds 93%, and the nitrite nitrogen removal rate exceeds 91%. A control experiment 1 is also set up in this example. In control experiment 1, the iron - carbon modified basalt fiber particle electrode biological carrier prepared by this application is not added during the construction of the anaerobic denitrification granular sludge reactor, and the other parameters are the same. The treatment results of Example 7 and the control experiment are shown in Table 1 below. It can be seen that whether the iron - carbon modified basalt fiber particle electrode biological carrier prepared by this application is added has an obvious impact on the subsequent denitrification effect.

[0134] Table 1

[0135]

[0136] After 140 days of operation of the reactor in this example, the performance parameter indicators of Anammox bacteria in a high-salt and high-nitrogen environment are as follows: Sludge performance: Sludge concentration (MLSS): 3000 - 4000 mg / L, Sludge sedimentation property (SVI): 50 - 70 mL / g, Sludge activity (SOUR): 0.5 - 0.8 mg O2 / g MLSS·h. Denitrification performance: Ammonia nitrogen removal rate: 93.5%, Nitrite nitrogen removal rate: 91.2%.

[0137] Example 8 Treatment of Simulated Wastewater with High Salt Content and Nitrogen II

[0138] Simulated wastewater was introduced into the anaerobic microbial denitrification reactor of Example 5 as an example for denitrification treatment.

[0139] The reactor operates in a continuous mode, with a hydraulic retention time of 24 h and the water temperature maintained at 30°C ± 1°C. The simulated wastewater enters the reactor through a peristaltic pump via the inlet pipe. In the reactor, marine anaerobic ammonium-oxidizing bacteria use ammonia nitrogen as the electron donor and nitrite nitrogen as the electron acceptor to convert the two into nitrogen gas and discharge it from the reactor, achieving efficient denitrification treatment of the simulated wastewater with high salt content and nitrogen.

[0140] Simulated wastewater parameters: NH4 + -N 110 mg / L, NO2 - -N 120 mg / L, NaCl 35 g / L. Among them, 0.01 mg of potassium dihydrogen phosphate, 0.1 mg of calcium chloride, 0.5 mg of potassium bicarbonate, 0.1 mg of magnesium sulfate, 0.1 mL of trace element I, and 0.1 mL of trace element II are added to each liter of simulated wastewater. The composition and content of trace element I are: ethylenediaminetetraacetic acid 1 g / L, ferrous sulfate 1 g / L; the composition and content of trace element II are: ethylenediaminetetraacetic acid 10 g / L, boric acid 0.01 g / L, manganese chloride 0.5 g / L, copper sulfate 0.1 g / L, zinc sulfate 0.1 g / L, nickel chloride 0.1 g / L, cobalt chloride 0.1 g / L, sodium selenate 0.1 g / L. All the chemicals used in this example were purchased from Shanghai Titan Scientific Co., Ltd. and Shanghai Yuanye Bio-Technology Co., Ltd. After the inlet solution was prepared, it was aerated with high-purity nitrogen for more than 30 minutes to remove the dissolved oxygen (<0.3 mg / L) in the solution.

[0141] After detection, within 0 - 30 days, the present application showed significant removal effects on ammonia nitrogen and nitrite nitrogen in the simulated wastewater. The removal rate of ammonia nitrogen exceeded 91%, and the removal rate of nitrite nitrogen was close to 90%. In this example, a control experiment 2 was also set up. In control experiment 2, the iron-carbon modified basalt fiber particle electrode biocarrier prepared by the present application was not added during the construction of the anaerobic denitrifying granular sludge reactor, and the remaining parameters were the same. The treatment results of Example 7 and the control experiment are shown in Table 2 below. It can be seen that the addition or non-addition of the iron-carbon modified basalt fiber particle electrode biocarrier prepared by the present application has an obvious impact on the subsequent denitrification effect.

[0142] Table 2

[0143]

[0144] In this example, after 140 days of operation of the reactor, the performance parameter indicators of Anammox bacteria in a high-salt and high-nitrogen environment are as follows: Sludge performance: Sludge concentration (MLSS): 3000 - 4000 mg / L, Sludge sedimentation property (SVI): 50 - 70 mL / g, Sludge activity (SOUR): 0.5 - 0.8 mg O2 / g MLSS·h. Denitrification performance: Ammonia nitrogen removal rate: 93.1%, Nitrite nitrogen removal rate: 91.4%.

[0145] Treatment of High-Salinity Nitrogen-Containing Actual Wastewater in Example 9

[0146] High-salinity nitrogen-containing actual wastewater was introduced into the anaerobic microbial denitrification reactor of Example 5 as an example for denitrification treatment. The hydraulic retention time was 24 h, and the water temperature was maintained at 30°C ± 1°C. Wastewater parameters: NH4 + -N 100 - 200 mg / L, NO2 - -N 100 - 260 mg / L, NaCl 25 - 35 g / L. Referring to Example 7 or 8, an appropriate amount of potassium dihydrogen phosphate, calcium chloride, potassium bicarbonate, magnesium sulfate, Trace Element I, and Trace Element II was added to each liter of simulated wastewater. After the influent solution was prepared, it was aerated with high-purity nitrogen for more than 30 minutes to remove the dissolved oxygen (<0.3 mg / L) in the solution.

[0147] After detection, within 30 days of stable operation, the present application showed significant removal effects on nitrite nitrogen and ammonia nitrogen in actual wastewater with different sodium chloride concentrations. The removal rate of ammonia nitrogen exceeded 93%, and the removal efficiency of nitrite nitrogen exceeded 91%. It can be seen that by adding the iron-carbon modified basalt fiber particle electrode biocarrier during the construction of the reactor, the present application domesticated and cultivated marine anaerobic ammonia-oxidizing bacteria, achieving efficient denitrification of high-salinity nitrogen-containing wastewater.

[0148] The above embodiments are only illustrative of the principles and effects of the present application and are not intended to limit the present application. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed in the present application should still be covered by the claims of the present application.

Claims

1. A preparation method of an iron-carbon modified basalt fiber particle electrode biological carrier, characterized in that, It includes the following steps: S a 1. After grinding and sieving the basalt fibers after pretreatment and etching treatment, soak them in the iron salt solution for 6 - 12 h at an immersion temperature of 50 - 90 °C; S a 2. Immerse the basalt fiber obtained in step S a 1 in a sodium p-toluenesulfonate solution, add pyrrole monomer and then add an iron salt solution, and react at room temperature for 12 - 24 h, where the mass ratio of basalt fiber, sodium p-toluenesulfonate, pyrrole monomer, and trivalent iron is 5.0:9.7 - 10.8:3.4 - 4.2:5.5 - 6.6; S a 3. Calcinate the basalt fiber obtained in step S2 in stages, where The first stage: Raise the temperature to 180 - 220 °C and keep it warm for 25 - 40 min. The second stage: Raise the temperature to 350 - 400 °C and keep it warm for 80 - 100 min. The third stage: Raise the temperature to 510 - 560 °C and keep it warm for 100 - 130 min.

2. The preparation method of the iron-carbon modified basalt fiber particle electrode biological carrier according to claim 1, characterized in that Step S a The pretreatment in 1 includes: soaking basalt fibers in an acetone solvent, heating to 38 - 42 °C and reacting for more than 1 h, and / or Step S a The etching treatment in 1 includes: placing basalt fibers in an etching solution and reacting at 20-90 °C for 1-24 h. The etching solution includes one or more of hydrochloric acid solution, sulfuric acid solution, hydrogen peroxide solution, and sodium hydroxide solution.

3. The preparation method of the iron-carbon modified basalt fiber particle electrode biological carrier according to claim 2, characterized in that, Step S a The etching treatment in 1 includes: first placing basalt fibers in hydrochloric acid solution, sulfuric acid solution, or sodium hydroxide solution and reacting at 20-90°C for 2-24 h, and then placing them in hydrogen peroxide solution and reacting at 40-90°C for 1-12 h.

4. The preparation method of the iron-carbon modified basalt fiber particle electrode biological carrier according to claim 1, characterized in that, Step S a Before step S a 3, it further includes: washing and purifying the basalt fibers obtained in step S a 2 with water and ethanol, and drying them under the condition of 60-70 °C.

5. A bio-carrier of iron-carbon modified basalt fiber particle electrode, characterized in that, It is prepared by the preparation method of the iron-carbon modified basalt fiber particle electrode biological carrier described in any one of claims 1 - 4.

6. The iron-carbon modified basalt fiber particle electrode biological carrier according to claim 6, characterized in that, The porosity of the iron-carbon modified basalt fiber particle electrode biological carrier is 90-93%, and the density is 1.03-1.15 g / cm 3 .

7. A construction method of an anaerobic denitrifying granular sludge reactor, characterized in that, It includes the following steps: S b 1. Inoculate the pretreated marine sediment into the reactor; S b 2. Add the iron-carbon modified basalt fiber particle electrode biological carrier prepared by the preparation method of the iron-carbon modified basalt fiber particle electrode biological carrier according to any one of claims 1-4, or the iron-carbon modified basalt fiber particle electrode biological carrier according to any one of claims 5-6; S b 3. Acclimation culture is carried out for 20 - 40 days under the conditions of a temperature of 28 - 32 °C and a stirring speed of 30 - 60 rpm. Among them, the influent ammonia nitrogen concentration is 100 - 120 mg / L, the nitrite nitrogen concentration is 100 - 120 mg / L, the sodium chloride concentration is 10 - 35 g / L, the pH is 7.0 - 8.0, and the hydraulic retention time is 10 - 24 hours.

8. An anaerobic denitrifying granular sludge reactor, characterized in that, It is constructed by the construction method of the anaerobic denitrifying granular sludge reactor described in claim 7.

9. Use of the iron-carbon modified basalt fiber particle electrode biological carrier according to claim 5 or 6 or the anaerobic denitrifying granular sludge reactor according to claim 8 in treating high-salinity nitrogen-containing wastewater, wherein, The sodium chloride content in the high-salinity nitrogen-containing wastewater is 10 - 35 g / L.

10. A treatment method for high-salinity nitrogen-containing wastewater, characterized in that, It includes feeding the high-salinity nitrogen-containing wastewater into the anaerobic denitrifying granular sludge reactor described in claim 8, and controlling the temperature in the reactor to be 28 - 32 °C and the stirring speed to be 30 - 60 rpm.

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