Preparation method of composite filler for synchronously removing composite pollutants in municipal sewage

Abstract

The invention relates to the technical field of water treatment materials, and discloses a preparation method of a composite filler for synchronously removing composite pollutants in municipal wastewater, which comprises the following steps: step 1, preparing 10%-20% of sulfur base, 15%-20% of iron base, 5%-10% of manganese base, 15%-20% of charcoal, 5%-10% of calcium base and 30%-40% of binder; step 2, crushing sulfur-based, iron-based and manganese-based materials until the particle size is less than or equal to 20 meshes, crushing a charcoal material until the particle size is less than or equal to 100 meshes, crushing a calcium-based material until the particle size is less than or equal to 200 meshes, and crushing a binder until the particle size is less than or equal to 200 meshes; and step 3, adding the materials in the step 2 into a roller granulator for granulation, and controlling the added moisture to be 10-15% in the granulation production process to ensure granulation forming and reduce defective products. Compared with the prior art, the filler has the advantages that the filler is poor in component synergism and non-ideal in removal efficiency, the remarkable effect of synchronously removing various pollutants in municipal tail water is difficult to realize, and the filler is short in service life, complex in production process, high in construction and operation investment cost and high in secondary pollution risk.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of water treatment materials, in particular to a preparation method of a composite filler for simultaneously removing composite pollutants in municipal sewage. BACKGROUND

[0002] At present, with the continuous acceleration of urbanization and industrialization and the continuous improvement of people's living standards, the discharge of tail water of municipal sewage plants is increasing, and the composite pollutants such as different concentrations of COD, ammonia nitrogen, nitrate nitrogen, total nitrogen, total phosphorus, new pollutants, fluoride ions and residual chlorine carried by the tail water are increasingly serious to the environment. As an important facility for urban sewage treatment, the treatment effect of the tail water of the municipal sewage plant is directly related to the water environment quality, the balance of the water ecological system and the sustainable development. However, the existing water treatment technology has obvious limitations in the application process of the composite pollutants in the tail water of the municipal sewage plant, and it is difficult to achieve good economic and environmental benefits.

[0003] There are various pollutants in the tail water of the municipal sewage plant, and different pollutants have different degrees of harm to the environment and human health. COD reflects the content of organic matter in water, and excessive COD will consume dissolved oxygen in water, leading to water anoxia and affecting the survival of aquatic organisms; total nitrogen (including ammonia nitrogen and nitrate nitrogen) is an important factor of water eutrophication, which can cause massive reproduction of algae and destroy the balance of water ecology; total phosphorus is also one of the key pollutants leading to water eutrophication; new pollutants are widely concerned in recent years, which have potential ecological toxicity and biological accumulation; excessive fluoride ions will threaten human health and destroy the ecological balance and biodiversity to different degrees; although residual chlorine can play a role in sterilization and disinfection to a certain extent, excessive residual chlorine will have adverse effects on aquatic organisms and the environment, and even cause secondary pollution risk.

[0004] The common treatment technologies for municipal tail water include activated carbon adsorption, sulfur-iron autotrophic denitrification, chemical precipitation, biological filter and the like, and have played a very significant water treatment effect, but the existing technologies still have obvious limitations. For example, the activated carbon adsorption method still cannot achieve deep denitrification and phosphorus removal, and the regeneration and recovery cost is high; in recent years, the sulfur-iron autotrophic denitrification technology has made great progress, but the component synergy of the filler is poor, the removal effect is not ideal, the new pollutants and residual chlorine are poor, and the filler cost is high, the energy consumption is increased, the service life is reduced in the alkaline environment, the process flow is complex, and secondary pollution may be caused; the chemical precipitation process produces sludge containing heavy metals, and cannot degrade new pollutants and the like.

[0005] With the increasingly stringent environmental emission standards and the high attention of the community to new pollutants, the above technical bottlenecks limit the industrialization development and market promotion of the technology to varying degrees, so the existing technology needs to be further improved, and a new type of composite filler with high efficiency, low cost and diversified functions is urgently needed. The industrial production of the new type of composite filler can be realized by component innovation and the use of non-burning granulation technology, the synchronous and efficient removal of composite pollutants in municipal tail water can be realized, the level of sewage treatment and resource utilization can be further improved, the pollutants can be greatly reduced, and the strategic goal requirements of "carbon peak and carbon neutral" and "pollution reduction and carbon reduction synergistic effect" can be deeply implemented. SUMMARY

[0006] (I) Technical problems to be solved

[0007] The technical problem to be solved by the present application is that the filler components have poor synergistic effect, the removal efficiency is not ideal, and it is difficult to achieve the significant effect of synchronous removal of multiple pollutants in municipal tail water, and there are problems of short service life, complex production process, high construction operation cost, secondary pollution risk, and the present application provides a preparation method of a composite filler for synchronous removal of composite pollutants in municipal sewage.

[0008] (II) Technical solutions

[0009] To solve the above technical problems, the technical solution provided by the present application is a preparation method of a composite filler for synchronous removal of composite pollutants in municipal sewage, which comprises the following steps:

[0010] Step 1: Prepare materials according to the following proportions: sulfur base 10%-20%, iron base 15%-20%, manganese base 5%-10%, biochar 15%-20%, calcium base 5%-10%, and binder 30%-40%;

[0011] Step 2: Crush the sulfur base, iron base and manganese base materials to a particle size of ≦20 mesh, the biochar material to a particle size of ≦100 mesh, the calcium base material to a particle size of ≦200 mesh, and the binder to a particle size of ≦200 mesh;

[0012] Step 3: Add the materials in step 2 to a drum granulator for granulation, control the water addition during the granulation production process to 10%-15%, and adopt intermittent water addition to ensure granulation forming and reduce defective products;

[0013] Step 4: Dry the composite filler product generated in step 3, and cure it for 7-10 days to ensure that its compressive strength meets the actual needs.

[0014] As an improvement, the proportions of the materials in step 1 are specifically 15% of sulfur base, 17.5% of iron base, 7.5% of manganese base, 17.5% of biochar, 7.5% of calcium base, and 35% of binder.

[0015] As an improvement, the sulfur base includes at least one of elemental sulfur, pyrite, pyrrhotite.

[0016] As an improvement, the iron base includes at least one of elemental iron, pyrite, pyrrhotite, and siderite.

[0017] As an improvement, the manganese base includes at least one of manganese oxide, manganese ore, ferromanganese ore, and manganese carbonate.

[0018] As an improvement, the biochar includes at least one of wheat straw, corn straw, corn cob, peanut shell, and rice husk.

[0019] As an improvement, the calcium base is at least one of limestone or bentonite.

[0020] As an improvement, the binder is a sulphoaluminate cement.

[0021] As an improvement, the biochar raw material is crushed and placed in a carbonization furnace for carbonization activation treatment, the carbonization temperature is 400-600 DEG C, and the carbonization time is 90 min.

[0022] As an improvement, the carbonization temperature of the wheat straw is preferably 400 DEG C, the carbonization temperature of the corn straw is preferably 450 DEG C, the carbonization temperature of the corn cob is preferably 600 DEG C, the carbonization temperature of the peanut shell is preferably 500 DEG C, and the carbonization temperature of the rice husk is preferably 500 DEG C.

[0023] (Three), beneficial effects

[0024] The present application has the following advantages:

[0025] 1. The sulfur base, the iron base, and the manganese base are used as electron donors for the autotrophic denitrification process, and the synergistic effect between the components further enhances the efficient and simultaneous removal of organic matter, denitrification, new pollutants, and other complex pollutants such as residual chlorine, greatly reducing the pollutant concentration in the tail water and reducing the risk of environmental pollution; compared with single filler removal rate, the removal rate is significantly improved;

[0026] 2. The manganese base can catalyze the oxidation of ammonia nitrogen and nitrite nitrogen to nitrate nitrogen, and the sulfur and iron bases can strengthen the decomposition of organic matter and new pollutants; the calcium base ore powder can promote the precipitation of calcium phosphate, thereby achieving the purpose of removing total phosphorus. At the same time, the manganese base and the calcium base ore powder ensure that the process product H+ produced in the autotrophic denitrification process is neutralized and relieved, ensuring that the pH value in the autotrophic denitrification process is in a better reaction condition and driving the smooth progress of the denitrification;

[0027] 3. The raw materials are widely available and relatively low in cost, realizing the resource recycling of agricultural waste and industrial solid waste, further improving the high added value of the product, and providing a huge market space for its large-scale application; the granulation process equipment is relatively simple, the energy consumption is low, no solid waste is generated, and no secondary pollution is caused.

[0028] 4. The filler application scenarios are diversified, such as tail water artificial wetland, river and lake ecological restoration, rural domestic sewage and black and odorous water treatment, aquaculture tail water treatment, non-point source pollution treatment and other polluted or eutrophic water bodies, which are simple to operate, have high and efficient purification effect, long service life and convenient operation and maintenance. BRIEF DESCRIPTION OF DRAWINGS

[0029] Fig. 1 is a composite filler product picture.

[0030] Fig. 2 is a composite filler laboratory simulated tail water composite pollutant removal rate table.

[0031] Fig. 3 is a composite filler laboratory simulated tail water composite pollutant removal and time table. DETAILED DESCRIPTION

[0032] The embodiments of the present application are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference signs represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by reference to the drawings are exemplary and are intended to explain the present application, and cannot be understood as a limitation of the present application.

[0033] In conjunction with the accompanying Figs. 1-3 A preparation method of a composite filler for synchronous removal of composite pollutants in municipal sewage, comprising the following steps:

[0034] Step 1: Prepare materials according to sulfur base 10% to 20%, iron base 15% to 20%, manganese base 5% to 10%, biochar 15% to 20%, calcium base 5% to 10%, and binder 30% to 40%;

[0035] Step 2: Crush the sulfur base, iron base, and manganese base materials to a particle size≦20 mesh, the biochar material to a particle size≦100 mesh, the calcium base material to a particle size≦200 mesh, and the binder to a particle size≦200 mesh;

[0036] Step 3: Add the materials in step 2 to a drum granulator for granulation, control the water addition 10% to 15% during the granulation production process, and take intermittent water addition to ensure granulation forming and reduce defective products;

[0037] Step 4: Shadow dry the composite filler product generated in step 3, and maintain for 7 to 10 days to ensure that the compressive strength meets the actual needs.

[0038] The proportion of each material in step 1 is specifically 15% of sulfur base, 17.5% of iron base, 7.5% of manganese base, 17.5% of biochar, 7.5% of calcium base, and 35% of binder.

[0039] The sulfur base includes at least one of elemental sulfur, pyrite, and pyrrhotite, and the mass fraction of the pyrite is 35% to 52% and the mass fraction of the pyrrhotite is 35% to 53% based on the total amount of sulfur element.

[0040] The iron base includes at least one of elemental iron, pyrite, pyrrhotite, and siderite, and the mass fraction of the pyrite is 47% to 64%, the mass fraction of the pyrrhotite is 46% to 64%, and the mass fraction of the siderite is 38% to 48% based on the total amount of iron element.

[0041] The manganese base includes at least one of manganese oxide, manganese ore, iron-manganese ore, and manganese carbonate, and the mass fraction of the manganese oxide is 75% to 80%, the mass fraction of the manganese ore and the iron-manganese ore is 25% to 35%, and the mass fraction of the manganese carbonate is 45% to 49% based on the total amount of manganese element.

[0042] The biochar includes at least one of wheat straw, corn straw, corn cob, peanut shell, and rice husk.

[0043] The calcium base is at least one of limestone or bentonite.

[0044] The binder is a sulphoaluminate cement, and the sulphoaluminate cement has a pH value of a slightly neutral, further reduces the acidity load of the autotrophic denitrification process, and makes the composite filler maintain a low alkalinity level and a high strength.

[0045] After the biochar raw material is crushed, the biochar raw material is placed in a carbonization furnace for carbonization and activation treatment, the carbonization temperature is 400°C to 600°C, and the carbonization time is 90 minutes.

[0046] The carbonization temperature of the wheat straw is preferably 400°C, the carbonization temperature of the corn straw is preferably 450°C, the carbonization temperature of the corn cob is preferably 600°C, the carbonization temperature of the peanut shell is preferably 500°C, and the carbonization temperature of the rice husk is preferably 500°C.

[0047] The production equipment of the novel composite filler is a roller granulator or a disc granulator, the roller granulator is generally required for small-batch production, the disc granulator is required for large-scale production, the particle size of the novel composite filler is 10 to 30 mm, the color is gray-black, the bulk density is 1100 to 1200 kg / m3, the compressive strength is not less than 300 N, and the porosity is not less than 40%, and the novel composite filler is a porous structure with a large internal specific surface area.

[0048] The application further provides a use of the novel composite filler in sewage treatment.

[0049] The application of the novel composite filler to the simultaneous removal of complex pollutants in municipal tail water.

[0050] The application provides a biological filter reaction device for municipal tail water composite pollutants.

[0051] The reaction device comprises a biological filter made of organic glass, a water inlet (including a water inlet pipe and a water stop clamp), a water outlet (including a water outlet pipe and a water stop clamp) and a peristaltic pump, and adopts an upflow water inlet mode.

[0052] The biological filter has a bottom diameter of about 30 cm, a height of about 1 m, is internally filled with a novel composite filler about 60 cm high, and is filled with 1-2 mm quartz sand about 20 cm high on the upper layer of the filler.

[0053] The biological filter is provided with five water inlets and five water outlets on each side, and adjacent water inlets or water outlets are spaced 20 cm apart, and sampling detection can be performed according to actual needs.

[0054] The application further provides a use method of the biological filter reaction device for municipal tail water composite pollutants.

[0055] (1) The novel composite filler is filled in the biological filter reaction device, and the filling height is about 50-60 cm, and the upper layer is filled with 20-30 cm of quartz sand;

[0056] (2) A certain amount of microbial strains is inoculated for biofilm cultivation, and the biofilm cultivation time is about 15-20 days;

[0057] (3) The units of the reaction device are connected, and the reaction device is started and operated;

[0058] (4) The HRT of the reaction device is set to 6 h;

[0059] (5) The simulated municipal tail water is introduced into the reaction device with successful biofilm cultivation, and a tail water composite pollutant removal test is performed.

[0060] Further, the microbial strains include anaerobic sludge or denitrifying bacteria containing sulfur-iron-based autotrophic denitrifying bacteria.

[0061] Further, the simulated municipal tail water is prepared by using laboratory ultrapure water and required reagents according to the pollutant concentration in the municipal tail water.

[0062] Example 1

[0063] The new composite filler prepared in the embodiment comprises five components, i.e. pyrite powder, corn cob biochar, manganese oxide, limestone powder and sulphoaluminate cement, wherein the particle size of the pyrite powder is ≦20 mesh, the particle size of the corn cob biochar is ≦100 mesh, the particle size of the manganese oxide is ≦20 mesh, the particle size of the limestone powder and the sulphoaluminate cement is ≦200 mesh, and the mass ratio of the components is 30:15:10:10:35. After the components are weighed, mixed and stirred uniformly, they are added into a drum granulator for granulation production. The new composite filler under the condition is obtained after being air-dried and cured for 10 days.

[0064] The new composite filler obtained has a particle size of 10-20 mm, a grey-black color, a bulk density of 1180 kg / m3, a compressive strength of 350 N, a porosity of 42% and a pH value of 7.10.

[0065] Example 2

[0066] The basic content of the embodiment is the same as that of Example 1, except that in the embodiment, the mass ratio of the components of pyrite powder, corn cob biochar, manganese oxide, limestone powder and sulphoaluminate cement is 20:20:10:10:40. After the components are weighed, mixed and stirred uniformly, they are added into a drum granulator for granulation production. The new composite filler under the condition is obtained after being air-dried and cured for 10 days.

[0067] The new composite filler obtained has a particle size of 10-20 mm, a grey-black color, a bulk density of 1140 kg / m3, a compressive strength of 315 N, a porosity of 43% and a pH value of 7.18.

[0068] Example 3

[0069] The basic content of the embodiment is the same as that of Example 1, except that in the embodiment, the mass ratio of the components of pyrite powder, corn cob biochar, manganese oxide, limestone powder and sulphoaluminate cement is 30:30:5:5:30. After the components are weighed, mixed and stirred uniformly, they are added into a drum granulator for granulation production. The new composite filler under the condition is obtained after being air-dried and cured for 10 days.

[0070] The new composite filler obtained has a particle size of 10-20 mm, a grey-black color, a bulk density of 1150 kg / m3, a compressive strength of 320 N, a porosity of 45% and a pH value of 6.85.

[0071] Comparative Example 1

[0072] The basic content of the comparative example is the same as that of Example 1, except that:

[0073] The mass ratio of pyrite powder, corn cob biochar, manganese oxide, limestone powder and sulphoaluminate cement component in the present comparative example is 30:15:10:10:35. Each component is weighed, mixed and stirred uniformly, and then added into a roller granulator for granulation production. After being air-dried and cured for 10 days, the new composite filler under the condition is obtained.

[0074] Finally, the new composite filler is obtained. The measured particle size of the obtained composite filler is 10-20 mm, the grey-black color, the bulk density is 1180 kg / m3, the compressive strength is 350 N, the porosity is 42%, and the pH value is 7.10.

[0075] The above-prepared new composite filler is filled in a biological filter reaction device with a filling height of 60 cm, inoculated with a certain amount of anaerobic sludge for biofilm cultivation for 15 days. After the biofilm is completed, the reaction device is started, and the prepared simulated tail water is introduced. The concentration of the composite pollutants in the tail water is shown in Table 1, and the removal effect of the new pollutants is shown in Fig. 3 The HRT is set to 6 h, and the reaction device is continuously operated for 120 d. Through the detection and analysis of the water quality, the removal rate of COD is 95%, the removal rate of ammonia nitrogen is 90%, the removal rate of nitrate nitrogen is 85%, the removal rate of total nitrogen is 87%, the removal rate of total phosphorus is 90%, the removal rate of residual chlorine is 98%, the removal rate of fluoride ions is 71%, and the removal rate of new pollutants is 90%. The new composite filler has a very significant removal effect on the composite pollutants in the simulated tail water, and the cost is relatively low, so the market prospect is broad.

[0076] Although the embodiments of the present application have been shown and described above, it should be understood that the above embodiments are exemplary and should not be construed as limiting the present application. Those skilled in the art can make changes, modifications, replacements, variations, deletions of part of the features, additions of features or recombination of features within the scope of the present application without departing from the principles and purposes of the present application. Any simple modification, equivalent change and modification made according to the innovative principles of the present application to the above embodiments shall still fall within the scope of the present application.

Claims

1. A method for preparing a composite packing material for the simultaneous removal of multiple pollutants from municipal wastewater, characterized in that: It comprises the following steps: Step 1: prepare materials according to the following proportions: 10-20% sulfur base, 15-20% iron base, 5-10% manganese base, 15-20% biochar, 5-10% calcium base, and 30-40% binder; Step 2: crush the sulfur base, iron base, and manganese base materials to a particle size of ≤20 mesh, the biochar material to a particle size of ≤100 mesh, the calcium base material to a particle size of ≤200 mesh, and the binder to a particle size of ≤200 mesh; Step 3: add the materials from Step 2 to a drum granulator for granulation, controlling the addition of moisture to 10-15% during the granulation process, and taking an intermittent water addition approach to ensure granulation shaping and reduce defective products; Step 4: shade dry the composite filler product generated in Step 3, and cure for 7-10 days to ensure that the compressive strength meets actual needs.

2. The preparation method of the composite filler for simultaneously removing the complex pollutants in the municipal sewage according to claim 1, characterized in that: The proportions of the materials in Step 1 are specifically 15% sulfur base, 17.5% iron base, 7.5% manganese base, 17.5% biochar, 7.5% calcium base, and 35% binder.

3. The method for preparing a composite packing material for simultaneous removal of multiple pollutants from municipal wastewater according to claim 1, characterized in that: The sulfur base includes at least one of elemental sulfur, pyrite, and pyrrhotite.

4. The method for preparing a composite packing material for simultaneous removal of multiple pollutants from municipal wastewater according to claim 1, characterized in that: The iron base includes at least one of elemental iron, pyrite, pyrrhotite, and siderite.

5. The method for preparing a composite packing material for simultaneous removal of multiple pollutants from municipal wastewater according to claim 1, characterized in that: The manganese base includes at least one of manganese oxide, manganese ore, iron-manganese ore, and manganese carbonate.

6. The method for preparing a composite packing material for simultaneous removal of multiple pollutants from municipal wastewater according to claim 1, characterized in that: The biochar includes at least one of wheat straw, corn straw, corn cob, peanut shell, and rice husk.

7. The method for preparing a composite packing material for simultaneous removal of multiple pollutants from municipal wastewater according to claim 1, characterized in that: The calcium base is at least one of limestone or bentonite.

8. The method for preparing a composite packing material for simultaneous removal of multiple pollutants from municipal wastewater according to claim 1, characterized in that: The binder is sulphoaluminate cement.

9. The method for preparing a composite packing material for simultaneous removal of multiple pollutants from municipal wastewater according to claim 6, characterized in that: After crushing the biochar raw material, place it in a carbonization furnace for carbonization and activation treatment, with a carbonization temperature of 400-600°C and a carbonization time of 90 minutes.

10. The method for preparing a composite packing material for simultaneous removal of multiple pollutants from municipal wastewater according to claim 9, characterized in that: The carbonization temperature for wheat straw is preferably 400°C, for corn straw is preferably 450°C, for corn cob is preferably 600°C, for peanut shell is preferably 500°C, and for rice husk is preferably 500°C.

Images