High-performance biological filler for advanced sewage treatment and preparation method of high-performance biological filler

Abstract

The invention relates to a high-performance biological filler for advanced sewage treatment and a preparation method of the high-performance biological filler. The biological filler comprises a nitrogen removal component, a phosphorus removal component, an inorganic carbon source component, an active component, 2-5 parts of a filler reinforcing component, a rare element component and a pore forming agent. The high-performance biological filler for advanced sewage treatment does not need any organic bonding agent or pore-forming agent, can simultaneously realize various functions of autotrophic denitrification, chemical phosphorus removal, heavy metal adsorption passivation, microbial adsorption biofilm formation and the like, has better physical properties, remarkably improves the sewage treatment effect, and greatly reduces the treatment cost.

Description

Technical Field

[0001] The invention relates to the field of biological fillers for sewage treatment, and in particular to a high-performance biological filler for deep sewage treatment and a preparation method thereof. Background Art

[0002] The main purpose of deep sewage treatment is to remove nitrogen, and it also has the functions of removing phosphorus, removing SS, removing heavy metals and color. At present, the denitrification process of sewage treatment plants mainly converts nitrogen pollutants in sewage into nitrogen gas and discharges it into the sewage system through biological nitrification + denitrification. Traditional denitrification uses heterotrophic microbial flora to reduce nitrate nitrogen with organic carbon sources as electron donors, and the reaction process requires the consumption of carbon sources. For the treatment of low-carbon and high-nitrogen wastewater, due to its low organic matter content, additional organic carbon sources need to be added in the traditional denitrification process to meet the heterotrophic denitrification demand for electron donors. Adding carbon sources such as methanol, sodium acetate, and glucose to achieve denitrification denitrification, on the one hand, there is a problem of insufficient or excessive addition of carbon sources that affects the effluent quality and may cause secondary pollution, and on the other hand, it also increases the operating cost. Sulfur autotrophic denitrification technology is based on S 2- 、S element、S2O3 2- and SO3 2- The reduced sulfur is used as electron donor, and CO3 2- Biological denitrification using inorganic carbon as the carbon source and sulfur autotrophic denitrification have been gradually applied to the purification of water with a low carbon-nitrogen ratio, such as groundwater, aquaculture tail water, municipal sewage and industrial wastewater, because of its advantages such as no need to add organic carbon source, low operating cost and low sludge yield.

[0003] At present, the sulfur autotrophic denitrification matrix used for biological denitrification mainly uses sulfur or sulfide. Since both are water-insoluble, during the biological denitrification sulfur autotrophic denitrification, one technology is to place sulfur or sulfide in a fixed bed reactor, but the use of a fixed bed reactor for sulfur autotrophic denitrification inevitably has problems such as easy blockage of the bed, large head loss and low denitrification efficiency; another technology is to melt sulfur at high temperature and load it on the surface of the filler used for sewage or surface water purification, but this technology requires special melting equipment to complete the coating loading under high temperature conditions, and the sulfur coating formed after loading is brittle and easy to crack, which greatly increases the operating difficulty of the method and the preparation cost of the sulfur coating. At the same time, due to the limited process conditions of the melting method, many substrates required for the sulfur autotrophic denitrification process cannot be added to the filler through the production process, which also reduces the denitrification efficiency of the process. At the same time, although there are many types of existing filler formulas, they have not fully considered the various nutrient matrices required for the metabolism of sulfur autotrophic microorganisms, and lack the functions of other demands for sewage treatment (dephosphorization, heavy metal removal, SS removal, etc.), which further limits the scope of use and efficiency of the filler.

[0004] In the existing sewage treatment technology, CN113697950A uses a substrate coating formed by applying the substrate required for sulfur autotrophic denitrification to a carrier for sewage treatment or surface water purification after hydration treatment, which will bring a huge workload to the operators of sewage treatment facilities, and this coating-type filler needs to be frequently filled, further increasing the cost and difficulty of project operation. At the same time, its formula lacks various trace elements and inorganic carbon source components required by sulfur autotrophic microorganisms, which will greatly limit the activity of microorganisms and reduce the denitrification and dephosphorization efficiency of the system.

[0005] CN116715357A combines multiple media and sulfur-based values ​​to form a composite filler through multi-layer stacking. However, this filler production method will result in a high proportion of inert components in the filler, significantly reduce the service life of the filler, and the production process is too complicated, and the quality stability of the filler product is low. At the same time, its filler formula also lacks various trace elements and inorganic carbon source components required by sulfur autotrophic microorganisms, which limits the efficiency of the process.

[0006] CN116813079A uses a chemical binder to mix the sulfur autotrophic denitrification matrix and then performs melt granulation. However, the binders polyvinyl acetate and sodium alginate used in this technology are both expensive chemical agents, which will greatly increase the production cost of the filler. In addition, the inorganic carbon source component used in this process is calcium carbonate, which may cause serious surface structural phenomena of the filler in the future and ultimately affect the actual denitrification efficiency of the process.

[0007] In CN116332344A, micro-electrolysis materials (activated carbon and reduced iron powder) and sulfur autotrophic denitrification base are filled into polyurethane sponge foam for drying and molding. However, the filler has the problem of weak physical properties, and the filler is easily damaged and lost in actual production and use, and the proportion of inert components is high, and the substrate consumption cycle required for sulfur autotrophy is very short, which further limits the scope of use of the filler.

[0008] Therefore, how to solve the defects of the existing technology is a difficult problem that needs to be overcome urgently. Summary of the invention

[0009] In order to overcome the shortcomings of the prior art, the present invention provides a high-performance biological filler for deep sewage treatment, which can simultaneously realize multiple functions such as autotrophic denitrification, chemical phosphorus removal, heavy metal adsorption and passivation, and microbial adsorption and biofilm formation, thereby ensuring the sewage treatment effect while greatly reducing the treatment cost.

[0010] Specifically, the present invention provides the following technical solutions:

[0011] One aspect of the present invention provides a high-performance biological filler for deep treatment of sewage, characterized in that it includes, by weight: 70-85 parts of denitrification components, 5-10 parts of phosphorus removal components, 3-10 parts of inorganic carbon source components, 1-2 parts of active components, 2-5 parts of filler reinforcement components, 1 part of rare element components, and 1-2 parts of pore-forming agents.

[0012] In some embodiments, the denitrification component includes sulfur.

[0013] In some embodiments, the phosphorus removal component includes ferrous carbonate and ferrous sulfate, and the mass ratio of ferrous carbonate to ferrous sulfate is 10:1.

[0014] In some embodiments, the inorganic carbon source component includes magnesium carbonate and calcium carbonate, and the mass ratio of the magnesium carbonate to the calcium carbonate is 2:1.

[0015] In some embodiments, the active components include ferroferric oxide, reduced iron powder, and activated carbon, and the mass ratio of the ferroferric oxide, reduced iron powder, and activated carbon is 3:1:1.

[0016] In some embodiments, the filler reinforcement component includes rice straw, loofah capsule, and rice husk powder, and the mass ratio of the rice straw, loofah capsule, and rice husk powder is 1:1:2.

[0017] In some embodiments, the rare element component is an aqueous solution including zinc sulfate, cobalt chloride, sodium selenate, sodium molybdate, manganese chloride and boric acid, and the mass fraction of the rare element is 5‰.

[0018] In some embodiments, the pore forming agent comprises sodium bicarbonate.

[0019] Another aspect of the present invention provides a method for preparing the high-performance biological filler for deep sewage treatment, characterized in that the preparation method comprises the following steps:

[0020] Step 1: Processing all solid components of the biological filler into powders of 100-200 mesh;

[0021] Step 2: Mix the components except the pore-forming agent in step 1 to obtain a mixed raw material;

[0022] Step 3: Add the mixed raw materials obtained in step 2 into a reactor, heat to 120-140° C. for mixing and melting, and maintain an anaerobic state in the reaction;

[0023] Step 4: Add the pore-forming agent into the mixed and melted material, stir rapidly for 15-30 seconds at a stirring rate of 150-300 rpm, and maintain the material temperature of 120-140°C and anaerobic state during this period;

[0024] Step 5: The material in the reactor is discharged for cooling and granulation;

[0025] Step 6: The cooled and screened filler particles are aged for 1-2 days; the aged filler particles can be packaged and sealed.

[0026] In some embodiments, the cooling granulation process in step 5 is selected from water-cooled direct molding or inverted plate air cooling.

[0027] Compared with the prior art, the advantages and positive effects of the present invention are:

[0028] The high-performance biological filler for deep treatment of sewage of the present invention does not require any organic adhesives and pore-forming agents, and can simultaneously realize multiple functions such as autotrophic denitrification, chemical phosphorus removal, heavy metal adsorption passivation, microbial adsorption and biofilm formation, etc., uses a mixed iron source (ferrous carbonate and ferrous sulfate) as a sewage phosphorus removal component; uses a mixed inorganic carbon source (magnesium carbonate and calcium carbonate) to provide the necessary alkalinity for sewage treatment at the same time; uses a plant straw powder combination (a combination of rice straw, loofah capsule and rice husk powder) to increase the physical properties of the filler; adds a water-soluble rare element component, which can provide the necessary carbon source and trace elements for microbial metabolism while removing nitrogen and phosphorus, so that the filler has better physical properties, the sewage treatment effect is significantly improved, and the treatment cost is greatly reduced. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0030] Example 1 High-performance biological filler for advanced sewage treatment

[0031] The high-performance biological filler for deep sewage treatment mainly combines multiple chemical components to simultaneously achieve multiple functions such as autotrophic denitrification, chemical phosphorus removal, heavy metal adsorption and passivation, and microbial adsorption and biofilm formation, and further removes the residual pollutants in the tail water (generally the sewage in the secondary sedimentation tank) after conventional sewage treatment processes. The formula of the biological filler is shown in the following table:

[0032]

[0033]

[0034] Example 2 High-performance biological filler for advanced sewage treatment

[0035] The high-performance biological filler for deep treatment of sewage of the present invention comprises, by weight: 80 parts of denitrification component, 6 parts of phosphorus removal component, 7 parts of inorganic carbon source component, 2 parts of active component, 3 parts of

[0036] Filler reinforcement component, 1 part rare element component, 1 part pore former.

[0037]

[0038]

[0039]

[0040] Example 3 High-performance biological filler for advanced sewage treatment

[0041] The high-performance biological filler for deep treatment of sewage of the present invention comprises, by weight: 72 parts of denitrification component, 10 parts of phosphorus removal component, 8 parts of inorganic carbon source component, 2 parts of active component, 5 parts of

[0042] Filler reinforcement component, 1 part rare element component, 2 parts pore former.

[0043]

[0044]

[0045] Example 4 High-performance biological filler for advanced sewage treatment

[0046] The high-performance biological filler for deep treatment of sewage of the present invention comprises, by weight: 85 parts of denitrification component, 5 parts of phosphorus removal component, 5 parts of inorganic carbon source component, 1 part of active component, 2 parts of

[0047] Filler reinforcement component, 1 part rare element component, 1 part pore former.

[0048]

[0049]

[0050] Example 4 Preparation method of high-performance biological filler for deep sewage treatment The preparation method of high-performance biological filler for deep sewage treatment comprises the following steps:

[0051] 1) All solid formula components are processed into 100-200 mesh powders by physical grinding and screening;

[0052] 2) This formula does not need to be produced by adding each component in steps. It only needs to mix all the components except the pore-forming agent described in step 1). The mixing is carried out by physical stirring at a stirring rate of 30-100 rpm and a mixing time of 5-10 minutes to obtain a mixed raw material.

[0053] 3) putting the mixed raw materials obtained in step 2) into a reactor, heating to 120-140° C. for mixing and melting, the mixing time required is 10-20 minutes, stirring is continued at a stirring rate of 60-180 rpm, and the anaerobic state in the reaction needs to be maintained during this period (which can be achieved by vacuuming and passing nitrogen);

[0054] 4) Add the pore-forming agent into the mixed and melted materials, stir rapidly for 15-30 seconds at a stirring rate of 150-300 rpm, and maintain the material temperature at 120-140° C. and anaerobic state;

[0055] 5) The material in the reactor is discharged for cooling and granulation treatment. There are two methods for cooling treatment: direct water-cooling molding and inverted plate air cooling. The water cooling method is: the molten material obtained in step 4) is directly passed through a sieve with an aperture of 1-3mm to form droplets and enter 10-20°C cooling water (tap water can be used) for rapid molding. The molded filler particles are screened to obtain 2-5mm filler particles. The inverted plate air cooling method is: the molten material obtained in step 40 is directly guided to a steel mold (with a size of 100cm*100cm*5cm) for room temperature cooling, and the cooling time is 30-45 minutes. The cooled material is physically crushed by an impact crushing process, and particles with a particle size of 2-5mm are selected as finished products. The undersize and oversize materials of the above two cooling treatments are returned to the reactor in step 3) as production raw materials;

[0056] 6) The cooled and screened filler particles are aged for 1-2 days and can be packaged and sealed.

[0057] Example 3 Application of the high-performance biological filler for deep sewage treatment of the present invention in actual sewage treatment

[0058] Case 1, using the high-performance biological filler for deep treatment of sewage in Example 2, the pilot test data of sewage from a sewage plant in Longyan City (average value for 40 days of operation)

[0059]

[0060] The sewage after deep treatment has significantly improved in various indicators (total nitrogen, total phosphorus and SS), and the effluent quality is stable and reliable. The treatment cost is estimated to be about 0.07 yuan / m 3 , and unmanned intelligent management has been realized.

[0061] Case 2: Pilot test of deep treatment of wastewater from a mine in Shanghang County, Longyan City using the high-performance biological filler for deep treatment of wastewater in Example 3 (average value for 90 days of operation)

[0062]

[0063] The sewage after deep treatment has significantly improved in various indicators (total nitrogen, total phosphorus and SS). The concentration of heavy metal pollutants in the effluent is extremely low and meets the industry emission requirements. The treatment cost is estimated to be about 0.09 yuan / m 3 .

[0064] Case 3, using the high-performance biological filler for deep sewage treatment in Example 4, field data of an open water ecological restoration project in a lake in Xiamen (average value for 135 days of operation)

[0065]

[0066]

[0067] The water quality of the lake water after treatment has been significantly improved, the concentration of pollutants has been significantly reduced, and the color and odor of the effluent have also been improved to a certain extent. It can be used as an auxiliary means of surface water ecological restoration and control the impact of surface pollution sources on the ecosystem.

[0068] In summary, the sewage deep treatment high-performance biological filler of the present invention significantly improves the sewage treatment effect and greatly reduces the treatment cost.

[0069] Although some specific embodiments of the present invention have been described in detail by way of example, it will be appreciated by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present invention. It will also be appreciated by those skilled in the art that various modifications may be made to the embodiments without departing from the scope and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. A high-performance biological filler for deep sewage treatment, characterized in that: The composition comprises, by weight: 70-85 parts of denitrification components, 5-10 parts of phosphorus removal components, 3-10 parts of inorganic carbon source components, 1-2 parts of active components, 2-5 parts of filler reinforcement components, 1 part of rare element components, and 1-2 parts of pore formers.

2. The high-performance biological filler for deep treatment of sewage according to claim 1, characterized in that: The denitrification component includes sulfur.

3. The high-performance biological filler for deep treatment of sewage according to claim 1 or 2, characterized in that: The phosphorus removal component includes ferrous carbonate and ferrous sulfate, and the mass ratio of the ferrous carbonate to the ferrous sulfate is 10:

1.

4. The high-performance biological filler for deep treatment of sewage according to any one of claims 1 to 3, characterized in that: The inorganic carbon source component includes magnesium carbonate and calcium carbonate, and the mass ratio of the magnesium carbonate to the calcium carbonate is 2:

1.

5. The high-performance biological filler for deep treatment of sewage according to any one of claims 1 to 4, characterized in that: The active components include ferroferric oxide, reduced iron powder and activated carbon, and the mass ratio of the ferroferric oxide, reduced iron powder and activated carbon is 3:1:

1.

6. The high-performance biological filler for deep treatment of sewage according to any one of claims 1 to 5, characterized in that: The filler reinforcement component comprises rice straw, loofah capsule and rice husk powder, and the mass ratio of the rice straw, loofah capsule and rice husk powder is 1:1:

2.

7. The high-performance biological filler for deep treatment of sewage according to any one of claims 1 to 6, characterized in that: The rare element component is an aqueous solution including zinc sulfate, cobalt chloride, sodium selenate, sodium molybdate, manganese chloride and boric acid, and the mass fraction of the rare element is 5‰.

8. The high-performance biological filler for deep treatment of sewage as claimed in claim 7, characterized in that: The pore former includes sodium bicarbonate.

9. The method for preparing high-performance biological filler for deep treatment of sewage according to any one of claims 1 to 8, characterized in that: The preparation method comprises the following steps: Step 1: Processing all solid components of the biological filler into powders of 100-200 mesh; Step 2: Mix the components except the pore-forming agent in step 1 to obtain a mixed raw material; Step 3: Add the mixed raw materials obtained in step 2 into a reactor, heat to 120-140° C. for mixing and melting, and maintain an anaerobic state in the reaction; Step 4: Add the pore-forming agent into the mixed and melted material, stir rapidly for 15-30 seconds at a stirring rate of 150-300 rpm, and maintain the material temperature of 120-140°C and anaerobic state during this period; Step 5: The material in the reactor is discharged for cooling and granulation; Step 6: The cooled and screened filler particles are aged for 1-2 days; the aged filler particles can be packaged and sealed.

10. The preparation method according to claim 9, characterized in that: The cooling granulation process in step 5 is selected from water-cooling direct molding or inverted plate air cooling.

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