Sulfur-manganese composite autotrophic denitrification filler as well as preparation method and application thereof

Abstract

The invention discloses a sulfur-manganese composite autotrophic denitrification filler as well as a preparation method and application thereof, and belongs to the technical field of environmental functional materials and polluted water treatment. The sulfur-manganese composite autotrophic denitrification filler contains manganese salt, a sulfur-based component and a cement-based component, the manganese salt comprises one or more of manganese carbonate, calcium manganese ore and rhodochrosite; the sulfur-based component comprises sulfur and sulfur manganese ore; the cement-based component comprises cement, fly ash pottery sand, silica fume, blast furnace slag and metakaolin; the cement comprises one or more of Portland cement, iron aluminate cement and sulphoaluminate cement. The nitrogen removal efficiency of the sulfur-manganese composite autotrophic denitrification filler is superior to that of a sulfur autotrophic denitrification system, the sulfate concentration and nitrite nitrogen accumulation in effluent are remarkably reduced, the service life of the filler is prolonged, and the efficient utilization rate of the material is improved.

Description

Technical Field

[0001] The invention relates to the technical field of environmental functional materials and polluted water treatment, and more specifically to a sulfur-manganese composite autotrophic denitrification filler and a preparation method and application thereof. Background Art

[0002] With the growth of the world's population, nitrogen and phosphorus pollution in the water environment has become a major environmental problem. At present, most of my country's municipal sewage discharges comply with the Class A emission standard of the "Pollutant Discharge Standard for Urban Wastewater Treatment Plants (GB18918-2002)". According to this standard, the concentration of TN should be less than 15mg / L and the concentration of TP should be less than 0.5mg / L. However, the IV level requirements for TN and TP (lakes and reservoirs) in the "Surface Water Environmental Quality Standard (GB3838-2002)" are 1.5mg / L and 0.1mg / L respectively. High nitrogen and phosphorus content can easily lead to eutrophication of water bodies, so it is necessary to perform deep denitrification on the sewage tail water to remove nitrogen and phosphorus.

[0003] Due to the lack of carbon sources in urban sewage, heterotrophic denitrification cannot be fully realized, and adding additional organic carbon sources will increase costs and cause secondary pollution. Therefore, hydrogen, sulfur compounds (sulfur and sulfide), iron (Fe 2+ ) are becoming more and more popular as electron donors. Among them, sulfur autotrophic denitrification refers to the process in which sulfur autotrophic denitrifying bacteria use reduced sulfur as an electron donor and inorganic carbon sources as carbon sources to convert NO3 - -N is reduced to N2, as shown in equation (1): 55S+50NO3 - +20CO2+38H2O+4NH4 + →4C5H7O2N+55SO4 2- +25N2+64H + However, this process will produce a large amount of SO4 2- , which may exceed the US EPA drinking water limit of 250mg / L SO4 2- In addition, sulfates can threaten many structural components with corrosion damage, including dams, concrete pavements, bridge piers and concrete piles, thus affecting their mechanical and durability properties.

[0004] At the same time, biofilters, artificial wetlands and fluidized bed technologies are commonly used technologies suitable for small and medium-sized sewage treatment. They mostly use granular fillers as biofilms and denitrification and phosphorus removal carriers to construct autotrophic denitrification systems. However, the current common fixed bed or fluidized bed reactors have the disadvantages of cumbersome internal filler replacement steps, non-adjustable filler density, and large water flow pressure drop. Therefore, there is still a technical need for an efficient and economical application device.

[0005] Therefore, there is still an urgent need for a sulfur autotrophic denitrification and denitrification and dephosphorization filler with good denitrification and dephosphorization effects. Summary of the invention

[0006] 1. Technical problem to be solved by the invention

[0007] In view of the problems that the denitrification and phosphorus removal fillers based on sulfur autotrophic denitrification in the prior art have poor denitrification and phosphorus removal treatment effects, a sulfur-manganese composite autotrophic denitrification filler is provided to improve the removal rate of nitrogen and phosphorus pollutants and significantly reduce the concentrations of sulfate and nitrite nitrogen in the effluent. At the same time, a preparation method and application of the sulfur-manganese composite autotrophic denitrification filler are provided.

[0008] 2. Technical solution

[0009] In order to achieve the above object, the technical solution provided by the present invention is:

[0010] The present invention provides a sulfur-manganese composite autotrophic denitrification filler;

[0011] The sulfur-manganese composite autotrophic denitrification filler contains manganese salt, sulfur-based components and cement-based components;

[0012] The manganese salt includes one or more of manganese carbonate, calcite and rhodochrosite;

[0013] The sulfur-based components include sulfur and pyrophyllite;

[0014] The cement-based components include cement, fly ash clay, silica fume, blast furnace slag and metakaolin; wherein the cement includes one or more of silicate cement, ferroaluminate cement and sulphoaluminate cement.

[0015] It should be noted that the sulfur-based components in the sulfur-manganese composite autotrophic denitrification filler can provide electrons for autotrophic denitrifying bacteria, and the slow-release property of sulfur in the sulfide manganese ore helps to maintain a long-term stable supply of electron donors in the system. + Promoted Mn 2+ The release of Mn 2+ It provides additional electrons for denitrification and drives the autotrophic denitrification process. The denitrification performance of the sulfur-manganese autotrophic denitrification system is significantly better than that of the sulfur autotrophic denitrification system, which indicates that the synergistic effect between sulfur and manganese enhances the removal of nitrogen;

[0016] On the other hand, due to the alkalinity buffering effect of manganese salts, the pH value in the sulfur-manganese autotrophic denitrification system can be maintained around the optimal pH value for denitrification, which is conducive to the progress of denitrification.

[0017] Furthermore, the cement-based components are calculated as the total amount, and the cement-based components include the following substances by mass fraction: 10% to 60% cement, 10% to 30% fly ash and ceramic sand, 5% to 25% silica fume, 5% to 30% blast furnace slag, and 5% to 30% metakaolin;

[0018] Calculated based on the total amount of sulfur-based components, the sulfur-based components include sulfur and sulfomanganese ore, the mass fraction of the sulfur is 20% to 80%, and the mass fraction of the sulfomanganese ore is 20% to 80%.

[0019] It should be noted that the cement in the cement-based component is used to remove phosphorus, and the remaining components are used to reduce the alkalinity of the cement and improve the strength of the filler, so that the filler has lower alkalinity and higher strength.

[0020] Furthermore, the density of the sulfur-manganese composite autotrophic denitrification filler is 0.5-2.3 g / cm 3 , the porosity is 10% to 60%.

[0021] It should be noted that the sulfur-manganese composite autotrophic denitrification filler with the above density and porosity range can be used as a filler for fluidized bed and fixed bed reactors for sewage treatment, and can deeply remove nitrogen, phosphorus and other pollutants in sewage through the action of microorganisms. 2- The concentration of NO2 - -N accumulation is significantly reduced, so the sulfur-manganese composite autotrophic denitrification filler has a long service life and high utilization rate when used as a filler for a fluidized bed or fixed bed reactor.

[0022] Furthermore, the pH of the sulfur-manganese composite autotrophic denitrification filler is 6.0-9.0.

[0023] Furthermore, the sulfur-manganese composite autotrophic denitrification filler has a porous structure.

[0024] The present invention also provides a method for preparing the above-mentioned sulfur-manganese composite autotrophic denitrification filler, comprising the following steps:

[0025] S1, calcining and melting dry powder containing manganese salt, sulfur-based component and cement-based component to obtain an active component molten mixture;

[0026] S2, foaming the active component molten mixture obtained in step S1 by chemical foaming, cooling, forming and granulating to obtain a sulfur-manganese composite autotrophic denitrification filler with a target particle size;

[0027] Wherein, in step S1, the cement-based components are used as the total amount for calculation, and the cement-based components include the following substances by mass fraction: 10% to 60% cement, 10% to 30% fly ash and ceramic sand, 5% to 25% silica fume, 5% to 30% blast furnace slag, and 5% to 30% metakaolin;

[0028] Calculated based on the total amount of sulfur-based components, the sulfur-based components include sulfur and sulfomanganese ore, the mass fraction of the sulfur is 20% to 80%, and the mass fraction of the sulfomanganese ore is 20% to 80%;

[0029] The cement includes one or more of silicate cement, ferroaluminate cement and sulphoaluminate cement;

[0030] The manganese salt includes one or more of manganese carbonate, calcite and rhodochrosite.

[0031] It should be noted that the preparation method is to highly fuse the manganese salt, the sulfur-based component and the cement-based component by mixing and heating them to melt, and at the same time use a chemical foaming method to foam the molten mixture to obtain a sulfur-manganese composite autotrophic denitrification filler, so that the sulfur-manganese composite autotrophic denitrification filler has the characteristics of large specific surface area, low alkalinity, high strength-to-mass ratio, slow-release electron donor denitrification and calcium and aluminum ion phosphorus removal, which can achieve more microbial attachment and improve the utilization rate of microorganisms, thereby improving the removal rate of nitrogen and phosphorus pollutants; and, because it has a lower alkalinity and a higher strength-to-mass ratio, it will not be toxic to water microorganisms when used as an ecological filter slope; wherein the strength-to-mass ratio is the ratio of strength to mass.

[0032] Preferably, the cement is sulphoaluminate cement.

[0033] Furthermore, in step S1, the dry powder can be obtained by the following method:

[0034] The manganese salt, the sulfur-based component and the cement-based component are uniformly mixed to obtain dry powder.

[0035] Further, in step S1, the sulfhydryl component can be obtained by the following method:

[0036] The sulfur and the manganese pyroxene are uniformly mixed to obtain the sulfur-based component.

[0037] Furthermore, in step S1, the cement-based component can be obtained by the following method:

[0038] The cement, fly ash, ceramic sand, silica fume, blast furnace slag and metakaolin are uniformly mixed to obtain a cement-based component.

[0039] Furthermore, in step S1, the mass ratio of the manganese salt, the cement-based component and the sulfur-based component is 10:5:10 to 1:1:1.

[0040] Furthermore, in step S1, the calcination conditions include: temperature of 120-170°C, time of 15-120 min, heating rate of 1-5°C·min -1 .

[0041] Furthermore, in step S2, the chemical foaming method includes using a foaming agent for foaming.

[0042] Furthermore, calculated by mass, the added amount of the foaming agent is 1% to 15% of the total amount of the manganese salt, the sulfur-based component and the cement-based component.

[0043] Furthermore, the particle size of the foaming agent is 1 to 15 μm.

[0044] It should be noted that, by using the foaming agent with the above-mentioned particle size, the foaming agent can be distributed more evenly in the molten mixture of the active components, thereby obtaining a new type of sulfur-manganese composite autotrophic denitrification filler with a uniform and dense porous structure.

[0045] Furthermore, the foaming agent includes one or more of sodium bicarbonate, sodium percarbonate and 4,4'-oxybisbenzenesulfonyl hydrazide.

[0046] Preferably, the foaming agent is sodium bicarbonate.

[0047] Furthermore, in step S1, the particle size of the manganese salt is ≤0.2 μm.

[0048] It should be noted that the use of manganese salts with the above-mentioned particle size can achieve a more complete and uniform blending effect when the manganese salts are mixed with sulfur-based components and cement-based components, thereby promoting the synergistic effect among the components.

[0049] Specifically, the step S1 specifically comprises: placing a dry powder slurry containing a manganese salt, a sulfur-based component and a cement-based component in a crucible, and calcining and melting the slurry in a muffle furnace to obtain a molten mixture of active components.

[0050] Furthermore, in step S2, the cooling molding time is 0.5 to 6 hours.

[0051] Furthermore, the granulation method includes mechanical crushing or screening and classification.

[0052] Furthermore, the step S2 specifically comprises: foaming the active component molten mixture obtained in step S1 by chemical foaming, standing and cooling at room temperature to form and granulate to obtain sulfur-manganese composite autotrophic denitrification filler with target particle size.

[0053] The present invention also provides an application of the above-mentioned sulfur-manganese composite autotrophic denitrification filler in sewage treatment.

[0054] Furthermore, the sulfur-manganese composite autotrophic denitrification filler is used for nitrogen and phosphorus removal in sewage treatment.

[0055] The present invention also provides a reaction device for denitrification and dephosphorization.

[0056] The reaction device comprises N reactor units which are connected in sequence and arranged in a stepwise manner and are recorded as the first, the second, ... the N-1th, and the Nth, respectively, wherein N≥2;

[0057] The height difference between two adjacent reactor units is 100 to 300 mm;

[0058] The reactor unit comprises a water inlet module, a device main body module and a filler module;

[0059] The device main body module comprises a first cylinder having a bottom, wherein the bottom of the first cylinder is provided with a water inlet, the top is provided with a water outlet and the side wall is provided with a feed inlet;

[0060] The packing module includes a second cylinder, and M packing components are arranged from the bottom to the top of the second cylinder, and are sequentially recorded as the first, the second, ..., the M-1th, and the Mth, wherein M≥2, and there is a gap between two adjacent packing components;

[0061] The filler component is filled with an autotrophic denitrification filler, and the autotrophic denitrification filler is the above-mentioned sulfur-manganese composite autotrophic denitrification filler;

[0062] The water inlet module includes a water storage tank, which is connected to the water inlet, and the height of the water storage tank is not lower than the height of the first cylinder of the device main body module;

[0063] The filling module is inserted into the first cylinder through the feed port and is detachably connected to the first cylinder.

[0064] Furthermore, the water outlet of the N-1th device main body module is connected to the water storage tank of the Nth reactor unit.

[0065] Furthermore, the height of the gap between two adjacent filler components is 5 to 30 mm.

[0066] Further, when the height of the first cylinder is greater than the height of the packing module, when the packing module is inserted into the first cylinder through the feed port, the area above the top of the Mth packing component is the settling area, and the area below the top of the Mth packing component is the reaction area.

[0067] The height of the sedimentation zone is 1 / 2 to 1 / 10 of the height from the bottom of the first filler component to the top of the Mth filler component.

[0068] Furthermore, an overflow weir is provided above the settling area;

[0069] The outer wall of the overflow weir is connected to a water collecting tank, and the water outlet of the first cylinder is arranged in the water collecting tank.

[0070] Furthermore, the width of the water inlet is the same as the width of the water storage tank.

[0071] Furthermore, a vent valve is also provided at the bottom of the cylinder of the main module of the device.

[0072] Further, the filler assembly includes a support component and an autotrophic denitrification filler placed on the support component;

[0073] The supporting component is provided with a hole.

[0074] The present invention also provides the above-mentioned sulfur-manganese composite autotrophic denitrification filler, or the sulfur-manganese composite autotrophic denitrification filler prepared by the above-mentioned preparation method, or the above-mentioned denitrification and phosphorus removal reaction device in sewage treatment.

[0075] Furthermore, the above-mentioned sulfur-manganese composite autotrophic denitrification filler or the above-mentioned denitrification and phosphorus removal reaction device can be applied to denitrification and phosphorus removal in sewage treatment.

[0076] The present invention also provides a method for using the above-mentioned denitrification and dephosphorization reaction device, which is characterized by comprising the following steps:

[0077] A1. Fill the above-mentioned sulfur-manganese composite autotrophic denitrification filler into the filler module, and assemble the filler module into the device main body module;

[0078] A2, inoculate microorganisms to form biofilm;

[0079] A3, connecting the reactor units in sequence and starting the reaction device;

[0080] A4. Introduce sewage into the started-up reaction unit to carry out nitrogen and phosphorus removal treatment.

[0081] Furthermore, the microorganisms include anaerobic sludge or bacterial agents containing sulfur autotrophic denitrifying bacteria.

[0082] 3. Beneficial effects

[0083] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0084] (1) The sulfur-manganese composite autotrophic denitrification filler provided by the present invention has a sulfur-based component that can provide electrons for autotrophic denitrifying bacteria, wherein the slow-release property of sulfur in the sulfide manganese ore helps to maintain a long-term stable supply of electron donors in the system. At the same time, the H generated in the autotrophic denitrification process + Promoted Mn 2+The release of Mn 2+ It provides additional electrons for denitrification and drives the autotrophic denitrification process. The denitrification performance of the sulfur-manganese autotrophic denitrification system is significantly better than that of the sulfur autotrophic denitrification system, which indicates that the synergistic effect between sulfur and manganese enhances the removal of nitrogen;

[0085] On the other hand, due to the alkalinity buffering effect of manganese salts, the pH value in the sulfur-manganese autotrophic denitrification system can be maintained around the optimal pH value for denitrification, which is conducive to the progress of denitrification.

[0086] (2) The sulfur-manganese composite autotrophic denitrification filler provided by the present invention has a density of 0.5 to 2.3 g / cm 3 The porosity is 10% to 60%, which can be used as fillers in fluidized beds and fixed bed reactors for sewage treatment. Through the action of microorganisms, pollutants such as nitrogen and phosphorus in sewage can be deeply removed. And the effluent SO4 after being treated by sulfur-manganese composite autotrophic denitrification filler 2- The concentration of Mn 2+ The autotrophic denitrification process, which is an electron donor, reduces SO4 2- The amount of production is shown in equation (2): On the other hand SO4 2- With Mn 2+ Will produce precipitation to reduce SO4 2- Concentration; NO2 - -N accumulation is significantly reduced, so the sulfur-manganese composite autotrophic denitrification filler has a long service life and high utilization rate when used as a filler for a fluidized bed or fixed bed reactor.

[0087] (3) The preparation method of the sulfur-manganese composite autotrophic denitrification filler provided by the present invention comprises the following steps: mixing a manganese salt, a sulfur-based component and a cement-based component, heating and melting the mixture to achieve a high degree of fusion; and simultaneously foaming the molten mixture by chemical foaming to obtain the sulfur-manganese composite autotrophic denitrification filler, so that the sulfur-manganese composite autotrophic denitrification filler has the characteristics of large specific surface area, low alkalinity, high strength-to-mass ratio, slow-release electron donor denitrification and calcium and aluminum ion dephosphorization, and can achieve more microbial attachment, improve microbial utilization rate, and thus improve the removal rate of nitrogen and phosphorus pollutants; and, because it has a lower alkalinity and a higher strength-to-mass ratio, the filler will not be toxic to water microorganisms when used in sewage treatment, for example, it can be used in water treatment equipment or in ecological filter slopes.

[0088] (4) In the denitrification and phosphorus removal reaction device provided by the present invention, the reactor units connected in sequence and arranged in a stepped manner can effectively reduce the use of water pumps and other devices, reduce equipment costs and operating energy consumption; the filler module fixes the filler in the second cylinder, and can be disassembled and pulled out as a whole when the filler is replaced, which is simple and convenient to operate; and the stacked filler can effectively reduce the pressure drop. When working in coordination with the reactor units arranged in a stepped manner, the sewage and the filler are in contact more evenly, ensuring a good water outlet effect; the sedimentation area can effectively settle the suspended matter and microorganisms, avoid the loss of microorganisms and ensure the denitrification and phosphorus removal effect of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0089] Figure 1 This is a schematic diagram of the structure of the reaction device for denitrification and dephosphorization in Example 3 of the present invention.

[0090] Figure 2 It is a schematic diagram of the left view of the main module of the device in Example 3 of the present invention.

[0091] Figure 3 This is a schematic diagram of the cross-sectional structure of the filler module in Example 3 of the present invention.

[0092] Figure 4 It is a schematic diagram of the local structure of the connection between the filling module and the device main body module in Example 3 of the present invention.

[0093] Figure 5 This is a physical picture of the sulfur-manganese composite autotrophic denitrification filler of Example 4 of the present invention.

[0094] Figure 6 (a) NO3 of the sulfur-manganese composite autotrophic denitrification filler in Example 4 of the present invention - -N removal effect diagram and (b) PO4 3- -P removes the effect picture.

[0095] Explanation of the symbols in the schematic diagram:

[0096] 110. water inlet pipe; 111. water inlet valve; 120. water storage tank; 210. first cylinder; 220. drain valve; 230. sedimentation zone; 240. overflow weir; 250. water collecting tank; 260. water outlet pipe; 261. water outlet valve; 270. flange connection port; 271. flange bolt hole; 280. reaction zone; 310. second cylinder; 311. flange blind plate; 320. packing assembly; 321. supporting component. DETAILED DESCRIPTION

[0097] The present disclosure may be more easily understood by reference to the following description in conjunction with examples, all of which constitute a part of the present disclosure. It should be understood that the present disclosure is not limited to the specific products, methods, conditions or parameters described and / or illustrated herein. Further, the terms used herein are only used for the purpose of describing specific embodiments by way of example and are not intended to be limiting unless otherwise indicated.

[0098] It should also be understood that, for the sake of clarity, certain features of the present disclosure may be described herein in the context of separate embodiments, but may also be provided in combination with each other in a single embodiment. That is, unless clearly incompatible or specifically not included, each separate embodiment is considered to be combinable with any other embodiment, and the combination is considered to represent another different embodiment. Conversely, for the sake of simplicity, the various features of the present disclosure described in the context of a single embodiment may also be provided individually or in any sub-combination. Finally, although a particular embodiment may be described as part of a series of steps or part of a more general structure, each step or substructure itself may also be considered to be an independent embodiment.

[0099] Unless otherwise indicated, it should be understood that each individual element in a list and each combination of individual elements in the list will be interpreted as a different embodiment. For example, a list of embodiments represented as "A, B, or C" should be interpreted to include embodiments "A", "B", "C", "A or B", "A or C", "B or C", or "A, B, or C".

[0100] In the present disclosure, the singular forms of the articles "a," "an," and "the" also include the corresponding plural references, and a reference to a specific value includes at least that specific value unless the context clearly indicates otherwise. Thus, for example, a reference to "a substance" is a reference to at least one of that substance and equivalents thereof.

[0101] When items are described by using the conjunction terms "... and / or...," etc., the description should be understood to include any one of the associated listed items and all combinations of one or more thereof.

[0102] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention belongs; the terms used herein and / or include any and all combinations of one or more of the associated listed items.

[0103] In the following examples, if no specific conditions are specified, the experiments were carried out under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used, if no manufacturer is specified, are all conventional products that can be purchased commercially.

[0104] The present invention is further described below in conjunction with specific examples, but the examples do not limit the present invention in any form. Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in the art. The essential characteristics and remarkable effects of the present invention can be reflected from the following examples, and the described embodiments are part of the embodiments of the present invention, rather than all the embodiments, and therefore, they do not limit the present invention in any way, and those skilled in the art make some non-essential improvements and adjustments based on the content of the present invention, which all belong to the protection scope of the present invention.

[0105] Example 1

[0106] In this embodiment, the components are uniformly mixed according to the mass ratio of manganese salt, cement-based component and sulfur-based component of 1:1:10, and heated at 2°C·min -1 The mixture was heated to 160°C at a heating rate of 1.50°C and calcined for 1.5 h to obtain a molten mixture of active components.

[0107] Then add a foaming agent 4,4'-oxybisbenzenesulfonyl hydrazide, the foaming agent particle size is 15 μm, and the amount of the foaming agent added is 1% of the total mass of the manganese salt, cement-based component and sulfur-based component. Finally, cool and mold at room temperature for 5 hours to prepare a sulfur-manganese composite autotrophic denitrification filler.

[0108] The density of the obtained sulfur-manganese composite autotrophic denitrification filler is about 0.91g / cm 3 , porosity is 45.9% and pH is 6.15.

[0109] The manganese salt is rhodochrosite with a particle size of 0.1 μm; cement, fly ash and clay sand, silica fume, blast furnace slag and metakaolin are uniformly mixed to obtain a cement-based component, which includes the following substances by mass fraction: 50% cement, 20% fly ash and clay sand, 15% silica fume, 5% blast furnace slag and 10% metakaolin, wherein the cement is sulphoaluminate cement; sulfur and thiomanganese ore are uniformly mixed to obtain a sulfur-based component, which includes the following substances by mass fraction: 60% sulfur and thiomanganese ore, calculated based on the total amount of the sulfur-based component.

[0110] Example 2

[0111] The basic content of this embodiment is the same as that of embodiment 1, except that: in this embodiment, the mass ratio of manganese salt, cement-based component and sulfur-based component is 10:4:5, each component is evenly mixed, heated to 120°C and calcined and melted for 1 hour to obtain a molten mixture of active components; the amount of sodium percarbonate added as a foaming agent is 3% of the total mass of the manganese salt, cement-based component and sulfur-based component. Finally, after cooling and molding for 2 hours, the sulfur-manganese composite autotrophic denitrification filler is prepared. The density of the obtained sulfur-manganese composite autotrophic denitrification filler is greater than that of water. The density of the obtained sulfur-manganese composite autotrophic denitrification filler is measured to be about 2.25g / cm 3 , porosity is 19.8% and pH is 7.53.

[0112] Example 3

[0113] Combination Figure 1-Figure 4 The present invention also provides a reaction device for nitrogen removal and phosphorus removal, the reaction device comprising N reactor units connected in sequence and arranged in a stepwise manner, and recorded in sequence as the first, the second, ... the N-1th, the Nth, wherein N≥2, and the height difference between two adjacent reactor units is 100-300 mm. For example, the reaction device may comprise 3 or 5 reactor units connected in sequence and arranged in a stepwise manner, which is not specifically limited herein.

[0114] The reactor unit includes a water inlet module, a device body module and a filler module. The device body module includes a first cylinder 210 with a bottom. The first cylinder 210 is provided with a water inlet at the bottom, a water outlet at the top and a feed inlet on the side wall.

[0115] The packing module includes a second cylinder 310, and M packing assemblies 320 are arranged from the bottom to the top of the second cylinder 310, and are sequentially recorded as the first, the second, ... the M-1th, the Mth, and there is a gap between two adjacent packing assemblies 320, wherein M≥2. Preferably, the M packing assemblies 320 are arranged in parallel in the second cylinder 310. The packing assembly 320 is filled with an autotrophic denitrification filler, and the autotrophic denitrification filler can be a sulfur-manganese composite autotrophic denitrification filler in the embodiment. The water inlet module includes a water storage tank 120, which is connected to the water inlet, and the height of the water storage tank 120 is not lower than the height of the first cylinder 210 of the main module of the device to ensure that the sewage can flow out from the outlet. The packing module is inserted into the first cylinder 210 through the feed port, and the second cylinder 310 is detachably connected to the first cylinder 210.

[0116] It should be noted that the reactor units connected in sequence and arranged in a stepped manner can effectively reduce the use of devices such as water pumps, reduce equipment costs and operating energy consumption; the packing components 320 arranged in parallel in the packing module can effectively reduce the pressure drop; moreover, when operating in coordination with multiple reactor units distributed in a stepped manner, the sewage and the sulfur-manganese composite autotrophic denitrification packing are in contact more evenly, ensuring a good water outlet effect; when replacing the packing, the packing module can be disassembled and pulled out as a whole, and the operation is simple and convenient.

[0117] As a specific embodiment, the first cylinder 210 is square, and a bottom plate may be provided at the bottom of the first cylinder 210, the water inlet is provided at the bottom of one side of the first cylinder 210, and the water outlet is the other end of the first cylinder 210. The second cylinder 310 in the packing module is also square, and the size of the outer wall of the second cylinder 310 is substantially the same as the size of the inner wall of the first cylinder 210, forming a drawer-type structure to accommodate the packing module. As an optional embodiment, a bottom plate may also be provided at the bottom of the second cylinder 310. The packing module is inserted into the first cylinder 210 through the feed port, and a side wall of the second cylinder 310 cooperates with the feed port of the first cylinder 210, for example, the side wall of the second cylinder 310 is consistent with the feed port of the first cylinder 210 in size, so that sewage will not flow out from the connection between the two. The second cylinder 310 may be provided with 6 packing assemblies 320 in sequence from bottom to top from the bottom to the top. Moreover, the four sides of the filler assembly 320 are connected to the second cylinder 310, and the sewage in the reactor unit can fully contact and react with the filler in the filler assembly 320. A water outlet is also provided at the bottom of one side of the second cylinder 310, and is connected to the water outlet of the first cylinder 210. Specifically, the sewage enters the filler module in the reactor unit from the water inlet at the bottom, and fully contacts and reacts with the autotrophic denitrification filler to achieve nitrogen and phosphorus removal, and then flows out from the water outlet.

[0118] As an optional embodiment, the feed port of the first cylinder 210 is provided with a flange connection port 270, and the first cylinder 210 is provided with a flange blind plate 311 connected to the flange connection port 270. The flange blind plate 311 and the flange connection port 270 can be connected through a flange bolt hole 271, and a rubber gasket is embedded in the connection to seal the side wall of the first cylinder 210.

[0119] Furthermore, the height of the gap between two adjacent filler assemblies 320 is 5 to 30 mm, and the packing density of the filler can be reasonably adjusted to ensure the treatment effect. As an optional embodiment, the height of the gap between any two adjacent filler assemblies 320 is the same.

[0120] Furthermore, combined with Figure 4, when the height of the first cylinder 210 is greater than the height of the second cylinder 310 of the packing module, and the packing module is inserted into the first cylinder 210 through the feed port, the area above the top of the Mth packing assembly 320 is the settling zone 230, and the area below the top of the Mth packing assembly 320 is the reaction zone 280. As an optional embodiment, the height of the settling zone 230 is 1 / 2 to 1 / 10 of the height from the bottom of the first packing assembly 320 to the top of the Mth packing assembly 320, which can effectively settle suspended matter and microorganisms, avoid the loss of microorganisms and ensure the denitrification and phosphorus removal effect of the system.

[0121] An overflow weir 240 is arranged above the sedimentation zone 230; the outer wall of the overflow weir 240 is connected to a water collecting tank 250, and the outlet of the first cylinder 210 is arranged in the water collecting tank 250. The water collecting tank 250 can be used to collect the treated sewage after sedimentation in the sedimentation zone 230. The treated sewage in the water collecting tank 250 can be discharged through the outlet. For example, when the treated sewage in the water collecting tank 250 does not meet the standard, it can be discharged to the next reactor unit for further treatment. As a specific embodiment, the cross-sectional area of ​​the overflow weir 240 is the same as the cross-sectional area of ​​the sedimentation zone 230, and the water collecting tank 250 is connected to the outer wall of the overflow weir 240 by welding. Moreover, the bottom of the water collecting tank 250 is 50 to 100 mm lower than the highest point of the overflow weir 240, the top of the water collecting tank 250 is 10 to 50 mm higher than the highest point of the overflow weir 240, and the width of the water collecting tank 250 is 30 to 100 mm.

[0122] Further, the filler assembly 320 includes a support component 321 and an autotrophic denitrification filler placed on the support component 321, and a plurality of holes are provided on the support component 321 to allow sewage to pass through without causing the filler to fall from the holes. The shape of the hole can be square or circular, and no specific restrictions are made here. The filler assembly 320 is connected to the second cylinder 310 through the support component 321. As an optional embodiment, the support component 321 is a filter screen; the pore size of the filter screen is 1 to 5 mm. The pore size of the filter screen should meet the condition that the autotrophic denitrification filler does not fall. As a specific embodiment, the filter screen is made of polytetrafluoroethylene (PTFE) or metal. As another optional embodiment, the filler assembly 320 includes two support components 321, and the autotrophic denitrification filler is filled between the two support components 321.

[0123] As an optional embodiment, the water inlet module also includes an inlet pipe 110, the outlet of which is connected to the water storage tank 120; and an inlet valve 111 is provided on the inlet pipe 110. The water outlet of the first cylinder 210 is connected to a water outlet pipe 260, and a water outlet valve 261 is provided on the water outlet pipe 260. A drain valve 220 is also provided at the bottom of the first cylinder 210. The drain valve 220 can be a valve such as a ball valve or a butterfly valve in the prior art, and is not specifically limited here. The outlet of the water outlet pipe 260 of the N-1th reactor unit is connected to the water storage tank 120 of the Nth reactor unit to realize the sequential connection of the N reactor units.

[0124] As an optional embodiment, when the first cylinder 210 is square, the width of the water storage tank 120 is the same as the width of the inner wall of one side of the first cylinder 210, so that the sewage has a relatively uniform flow rate when entering the second cylinder 310, which is conducive to improving the treatment effect. The highest point of the water storage tank 120 is 100-200mm higher than the water collection tank 250.

[0125] The method for using the denitrification and dephosphorization reaction device in this embodiment includes the following steps:

[0126] A1. Loading sulfur-manganese composite autotrophic denitrification filler into the filler module, and assembling the filler module into the device main body module;

[0127] A2, inoculate microorganisms to form biofilm;

[0128] A3, connecting the reactor units in sequence and starting the reaction device;

[0129] A4. Introduce sewage into the started-up reaction unit to carry out nitrogen and phosphorus removal treatment.

[0130] The microorganisms include anaerobic sludge or bacterial agents containing sulfur autotrophic denitrifying bacteria.

[0131] Step A1 specifically includes filling the sulfur-manganese composite autotrophic denitrification filler such as provided in any embodiment of the present invention into the filler assembly 320 of the filler module, and then inserting the filler assembly 320 through the feed port on one side of the first cylinder 210 in the device main body module, and then fixing the filler module to the first cylinder 210. Step A4 specifically includes introducing sewage into the first reactor unit in the reaction device, and the sewage treated by the first reactor unit enters the second reactor unit for treatment, and the subsequent steps are performed in sequence.

[0132] Example 4

[0133] The basic content of this embodiment is the same as that of embodiment 1, except that: in this embodiment, the mass ratio of manganese salt, cement-based component and sulfur-based component is 5:2:5, each component is evenly mixed, heated to 140°C for calcination and melting for 0.5h, and a molten mixture of active components is obtained; then a foaming agent, sodium bicarbonate, is added, the particle size of the foaming agent is 10μm, and the amount of the foaming agent added is 5% of the total mass of the manganese salt, cement-based component and sulfur-based component, and finally, the sulfur-manganese composite autotrophic denitrification filler is prepared after standing and cooling at room temperature for 4h. The density of the obtained sulfur-manganese composite autotrophic denitrification filler is about 1.08g / cm 3 , the porosity is 38.96% and the pH is 6.82.

[0134] The sulfur-manganese composite autotrophic denitrification filler prepared in this embodiment is as follows Figure 5 As shown. Figure 5 It can be seen that the prepared filler has a uniform and dense porous structure, and its surface is relatively rough, which is conducive to increasing the amount of microbial attachment, thereby improving the removal rate of nitrogen and phosphorus pollutants.

[0135] The sulfur-manganese composite autotrophic denitrification filler was crushed and the material with an average particle size of about 1 to 3 mm was screened out as filler, and the filler was loaded into the denitrification and phosphorus removal reaction device in Example 3. The device used 3 reactor units, and 6 layers of filler were loaded in the filler module of each reactor unit. Then, anaerobic sludge was inoculated and culture solution was added (culture solution composition: KNO3 2.00g / L, NaHCO3 2.00g / L, KH2PO4 2.00g / L, MgCl2·6H2O 0.50g / L, NH4Cl 0.50g / L, FeSO4·7H2O 0.01g / L, Na2S2O3·5H2O 5.00g / L), and the biofilm was completed after 7 days of cultivation, and the reaction device was started. Influent was introduced into the reaction device after the startup, with a flow rate of 120mL / min and a hydraulic retention time of 3h. The changes in the concentrations of nitrate nitrogen and phosphate phosphorus in the inlet and outlet water during the 90-day operation were shown in FIG. Figure 6 .like Figure 6 As shown, the average nitrate nitrogen in the inlet is 32.3 mg / L, the average nitrate nitrogen in the outlet is 0.67 mg / L, the average phosphate phosphorus in the inlet is 13.81 mg / L, and the average phosphate phosphorus in the outlet is 0.03 mg / L. The nitrite nitrogen concentration in the outlet is lower than the detection limit (0.003 mg / L), SO4 2- The concentration is 150.27 mg / L.

[0136] Comparative Example 1

[0137] The basic content of this comparative example is the same as that of Example 4, except that:

[0138] In this comparative example, the mass ratio of cement-based component to sulfur-based component is 1:10, and the components are uniformly mixed, heated to 140° C. for calcination and melting to obtain a molten mixture of active components;

[0139] Finally, a lightweight porous material was prepared. After measurement, the density of the lightweight porous material was about 0.73 g / cm 3 , porosity is 50.3% and pH is 6.03.

[0140] The lightweight porous material was crushed and sieved to obtain a material with an average particle size of about 1 to 3 mm as filler. The filler was loaded into the same application device as used in Example 4, inoculated with anaerobic sludge and added with culture fluid. After 7 days of culture, biofilm formation was completed and the reaction device was started. Influent was introduced into the reaction device after startup, with a flow rate of 120 mL / min and a hydraulic retention time of 3 h. During the 90-day operation, the average nitrate nitrogen in the influent was 32.3 mg / L, the average nitrate nitrogen in the effluent was 4.51 mg / L, the average phosphate phosphorus in the influent was 13.81 mg / L, and the average phosphate phosphorus in the effluent was 0.55 mg / L. The nitrite nitrogen concentration in the effluent was 0.35 mg / L, SO4 2- The concentration is 280.21 mg / L.

Claims

1. A sulfur-manganese composite autotrophic denitrification filler, characterized in that: The sulfur-manganese composite autotrophic denitrification filler contains manganese salt, sulfur-based components and cement-based components; The manganese salt includes one or more of manganese carbonate, calcite and rhodochrosite; The sulfur-based components include sulfur and pyrophyllite; The cement-based components include cement, fly ash clay, silica fume, blast furnace slag and metakaolin; wherein the cement includes one or more of silicate cement, ferroaluminate cement and sulphoaluminate cement.

2. The sulfur-manganese composite autotrophic denitrification filler according to claim 1, characterized in that: The density of the sulfur-manganese composite autotrophic denitrification filler is 0.5-2.3 g / cm 3 , the porosity is 10% to 60%.

3. The method for preparing the sulfur-manganese composite autotrophic denitrification filler according to any one of claims 1 to 2, characterized in that: S1, calcining and melting dry powder containing manganese salt, sulfur-based component and cement-based component to obtain an active component molten mixture; S2, foaming the active component molten mixture obtained in step S1 by chemical foaming, cooling, forming and granulating to obtain a sulfur-manganese composite autotrophic denitrification filler with a target particle size; Wherein, in step S1, the cement-based components are used as the total amount for calculation, and the cement-based components include the following substances by mass fraction: 10% to 60% cement, 10% to 30% fly ash and ceramic sand, 5% to 25% silica fume, 5% to 30% blast furnace slag, and 5% to 30% metakaolin; Calculated based on the total amount of sulfur-based components, the sulfur-based components include sulfur and sulfomanganese ore, the mass fraction of the sulfur is 20% to 80%, and the mass fraction of the sulfomanganese ore is 20% to 80%; The cement includes one or more of silicate cement, ferroaluminate cement and sulphoaluminate cement; The manganese salt includes one or more of manganese carbonate, calcite and rhodochrosite.

4. The method for preparing the sulfur-manganese composite autotrophic denitrification filler according to claim 3, characterized in that: In step S1, the mass ratio of the manganese salt, the cement-based component and the sulfur-based component is 10:5:10 to 1:1:

1.

5. The method for preparing the sulfur-manganese composite autotrophic denitrification filler according to claim 4, characterized in that: In step S1, the calcination conditions include: temperature of 120-170°C, time of 15-120 min, heating rate of 1-5°C·min -1 .

6. The method for preparing the sulfur-manganese composite autotrophic denitrification filler according to claim 5, characterized in that: In step S2, the chemical foaming method includes using a foaming agent for foaming; Calculated by mass, the amount of the foaming agent added is 1% to 15% of the total amount of the manganese salt, the sulfur-based component and the cement-based component; The granulation method includes mechanical crushing or screening and classification.

7. A reaction device for denitrification and dephosphorization, characterized in that: The reaction device comprises N reactor units which are connected in sequence and arranged in a stepwise manner and are recorded as the first, the second, ... the N-1th, and the Nth, respectively, wherein N≥2; The height difference between two adjacent reactor units is 100 to 300 mm; The reactor unit includes a water inlet module, a device main body module and a filler module. The device main body module comprises a first cylinder (210) having a bottom, the bottom of the first cylinder (210) is provided with a water inlet, the top is provided with a water outlet and the side wall is provided with a feed inlet; The packing module comprises a second cylinder (310), and M packing assemblies (320) are arranged from the bottom to the top of the second cylinder (310), and are sequentially recorded as the first, the second, ... the M-1th, and the Mth, wherein M≥2, and there is a gap between two adjacent packing assemblies (320); The filler assembly (320) is filled with an autotrophic denitrification filler, wherein the autotrophic denitrification filler is the sulfur-manganese composite autotrophic denitrification filler according to any one of claims 1 to 2 or the sulfur-manganese composite autotrophic denitrification filler prepared by the preparation method according to any one of claims 3 to 6; The water inlet module comprises a water storage tank (120), the water storage tank (120) is connected to the water inlet of the first cylinder (210), and the height of the water storage tank (120) is not lower than the height of the first cylinder (210) of the device main body module; The filling module is inserted into the first cylinder (210) through the feed port and is detachably connected to the first cylinder (210).

8. The denitrification and dephosphorization reaction device according to claim 7, characterized in that: The height of the gap between two adjacent filler components (320) is 5 to 30 mm; When the height of the first cylinder (210) is greater than the height of the packing module, and the packing module is inserted into the first cylinder (210) through the feed port, the area above the top of the Mth packing component (320) is the settling zone (230), and the area below the top of the Mth packing component (320) is the reaction zone (280), and the height of the settling zone (230) is 1 / 2 to 1 / 10 of the height from the bottom of the first packing component (320) to the top of the Mth packing component (320); An overflow weir (240) is arranged above the sedimentation area (230); the outer wall of the overflow weir (240) is connected to a water collecting tank (250), and the water outlet of the first cylinder (210) is arranged in the water collecting tank (250); The filler assembly (320) comprises a support component (321) and a sulfur-manganese composite autotrophic denitrification filler placed on the support component (321).

9. Use of the sulfur-manganese composite autotrophic denitrification filler as claimed in any one of claims 1 to 2, or the sulfur-manganese composite autotrophic denitrification filler prepared by the preparation method of any one of claims 3 to 6, or the denitrification and phosphorus removal reaction device as claimed in any one of claims 7 to 8 in sewage treatment.

10. A method for using the denitrification and dephosphorization reaction device according to any one of claims 7 to 8, characterized in that: The following steps are involved: A1. Load the autotrophic denitrification filler into the filler module, and assemble the filler module into the main module of the device; A2, inoculate microorganisms to form biofilm; A3, connecting the reactor units in sequence and starting the reaction device; A4. Sewage is introduced into the reaction device after startup to carry out nitrogen and phosphorus removal treatment.

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