Coal gangue-based composite material, preparation method and application thereof
By preparing coal gangue-based composite materials, the problem of poor nitrogen removal efficiency in sewage treatment plants has been solved, achieving efficient and economical nitrogen removal, avoiding secondary pollution, and improving sewage treatment efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-26
- Publication Date
- 2026-03-20
AI Technical Summary
Existing technologies are insufficient to effectively enhance denitrification without altering the operating processes of wastewater treatment plants, and may lead to secondary pollution of effluent and increased operating costs.
A coal gangue-based composite material was prepared by hot alkali activation and melt granulation. Combined with porous materials and surfactants, it enhances microbial activity and pollutant adsorption, provides the necessary carbon source, and improves denitrification efficiency.
Without altering existing facilities, it significantly improved wastewater denitrification, reduced operating costs, prevented secondary pollution of effluent, and enhanced pollutant degradation capabilities.
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Figure CN119551810B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the technical field of sewage treatment, and particularly relates to a coal gangue-based composite material and a preparation method and application thereof. BACKGROUND
[0002] In recent years, with the promulgation of the Water Ten Provisions and the continuous promotion of ecological civilization construction, the effluent indicators of sewage treatment are becoming higher and higher, and the local standards are becoming more and more stringent. It is increasingly difficult to meet the increasingly stringent effluent indicators of the national first-level A standard (COD: 50 mg / L, TN: 15 mg / L). The TN emission limit of the first-level sewage discharge standard in Zhejiang, Jiangsu and other places is 10 mg / L, and the COD emission limit is 30 mg / L. Some sewage treatment plants are still using some old treatment methods and operation processes, so it is urgent to improve the sewage treatment effect.
[0003] The general method for treating wastewater includes physical method, chemical method and biological method. Biological method is widely used due to its good treatment effect, low energy consumption and strong economic applicability. Biological method is divided into activated sludge method and biofilm method, and the activated sludge method is the mainstream method for treating wastewater in sewage treatment plants due to its good treatment effect, low treatment cost and strong applicability. The traditional activated sludge method takes activated sludge as the core, and the most common AAO method degrades COD through an aerobic tank, denitrifies nitrogen in an anoxic tank, and releases phosphorus in an anaerobic tank. If the carbon source is insufficient in the anoxic tank, the anoxic denitrification process is difficult to maintain high efficiency, and additional addition of carbon source will cause the operation cost to increase and the effluent quality to deteriorate. Moreover, the traditional sewage treatment plant has a large capital cost for upgrading and reconstruction, so it is a research hotspot in recent years to seek a method for strengthening the denitrification effect of sewage without changing the original operation process.
[0004] Preparation of high-efficiency biological filler is a simple, economical and convenient method to strengthen the denitrification of sewage, and the discharge requirements can be met without changing the basic facilities of the sewage plant. The prior art discloses a preparation method and application of immobilized bacteria-algae biological filler, and iron-carbon material is added to the immobilized bacteria-algae biological filler. Due to the micro-electrolysis effect of the iron-carbon material, the generated iron ions can participate in the electron transfer between microbial cells, enhance the respiration of microorganisms, and help to increase the biomass and improve the degradation capacity of the bacteria-algae symbiotic system to pollutants. Although nitrogen and phosphorus can be removed simultaneously, the reproduction of algae is limited, and only low-load nitrogen and phosphorus pollutants can be treated, and a carbon source needs to be supplemented, which may cause secondary pollution. The microbial activity is not fundamentally enhanced, and the population abundance is not improved, so that the denitrification effect is difficult to further improve. The prior art also discloses a sulfur / magnetic pyrite denitrification and phosphorus removal composite biological filler, a preparation method and application thereof. The biological filler is obtained by granulating sulfur, magnetic pyrite and shells through a physical method. The sulfur in the composite biological filler can act as an electron donor for autotrophic denitrification, the magnetic pyrite mainly composed of FeS can not only act as an electron donor for microbial denitrification, but also release iron ions to form iron phosphate precipitate with phosphate, so as to achieve the purpose of simultaneous denitrification and phosphorus removal, and the shells have the function of self-adapting pH adjustment. However, the sulfur / magnetic pyrite itself has complex composition and contains various heavy metal substances, and the effluent may exceed the standard of heavy metals.
[0005] Therefore, how to prepare clean, green and efficient microbial filler which can supplement carbon source to a certain extent, does not cause secondary pollution of effluent, enhances the activity of denitrifying microorganisms, provides necessary nutrients for the denitrification process, improves the pollutant degradation capacity and increases the efficiency of microbial denitrification is a problem to be solved. SUMMARY
[0006] The purpose of the present application is to provide a coal gangue-based composite material and a preparation method and application thereof.
[0007] In order to achieve the above purpose, the present application provides the following technical scheme:
[0008] The present application provides a coal gangue-based composite material, which comprises a coal gangue-based matrix material and a porous material loaded on the surface and pores of the coal gangue-based matrix material.
[0009] The preparation raw materials of the coal gangue-based matrix material comprise coal gangue, kaolin, carboxymethyl cellulose, cetyltrimethylammonium bromide, a binder, a surfactant and polydiallyl phthalate.
[0010] Preferably, the preparation raw materials of the coal gangue matrix material include coal gangue 40-50 parts, kaolin 2-6 parts, carboxymethyl cellulose 10-20 parts, cetyltrimethylammonium bromide 10-20 parts, adhesive 5-10 parts, surfactant 7-12 parts and polydiallyl phthalate 4-8 parts in mass fraction.
[0011] Preferably, the adhesive includes one or more of unsaturated polyester resin, phenolic resin, polyvinyl alcohol, alpha-cyanoacrylate, acrylate and epoxy resin.
[0012] Preferably, the surfactant includes one or more of sodium dodecyl sulfate and sodium dodecyl sulfate.
[0013] Preferably, the particle size of the coal gangue is 100-200 mesh.
[0014] The porous material includes activated carbon.
[0015] The particle size of the porous material is 100-200 mesh; and the mass ratio of the coal gangue to the porous material is 40-50:20-35.
[0016] Preferably, the coal gangue-based composite material is a porous material, and the porosity of the coal gangue-based composite material is 50-60%.
[0017] The application further provides a preparation method of the coal gangue-based composite material.
[0018] The coal gangue is activated by hot alkali using cetyltrimethylammonium bromide to obtain activated coal gangue.
[0019] The activated coal gangue, kaolin, carboxymethyl cellulose, adhesive and porous material are mixed to obtain a mixture.
[0020] The mixture, surfactant and polydiallyl phthalate are mixed, and then melt granulation is performed to obtain the coal gangue-based composite material.
[0021] Preferably, the temperature of the hot alkali activation is 100-200℃, and the time is 40-60 min.
[0022] Preferably, the temperature of the melt granulation is 800-1000℃, and the holding time is 1-2 h.
[0023] The application further provides application of the coal gangue-based composite material or the coal gangue-based composite material prepared by the preparation method in sewage treatment.
[0024] The application provides a coal gangue-based composite material, which comprises a coal gangue-based matrix material and porous materials loaded on the surface and pores of the coal gangue-based matrix material; and the preparation raw materials of the coal gangue-based matrix material comprise coal gangue, kaolin, carboxymethyl cellulose, cetyltrimethylammonium bromide, a binder, a surfactant and polydiallyl phthalate.
[0025] In the application, the positive charge groups on the surface of the cetyltrimethylammonium bromide are adsorbed on the negative charge points on the surface of the coal gangue, and the hydrophobic long carbon chains form organic phases in the form of hydrophobic bonds, so that the hydrophobicity of the coal gangue activated by hot alkali is enhanced, and the adsorption capacity for organic pollutants is significantly enhanced. The carboxymethyl cellulose has excellent biocompatibility and environmental friendliness, and has a large number of active groups on the surface, which can provide donors for the coordination reaction of metal cations. The coal gangue contains various metal elements (Fe, Ca and Mg, etc.), which can form metal bonds with the negative active groups on the carboxymethyl cellulose, and the two can cooperate with each other to increase the loading amount of microorganisms on the composite material, improve the utilization rate of organic carbon sources in wastewater, and further improve the treatment efficiency of the composite material on the wastewater. BRIEF DESCRIPTION OF DRAWINGS
[0026] Fig. 1 The figure is the removal effect of the coal gangue-based composite material obtained in Example 1 on pollutants;
[0027] Fig. 2 The figure is the removal effect of the coal gangue-based composite material obtained in Example 2 on pollutants;
[0028] Fig. 3 The figure is the removal effect of the coal gangue-based composite material obtained in Example 3 on pollutants. DETAILED DESCRIPTION
[0029] The application provides a coal gangue-based composite material, which comprises a coal gangue-based matrix material and porous materials loaded on the surface and pores of the coal gangue-based matrix material;
[0030] The preparation raw materials of the coal gangue-based matrix material comprise coal gangue, kaolin, carboxymethyl cellulose, cetyltrimethylammonium bromide, a binder, a surfactant and polydiallyl phthalate.
[0031] In the application, the preparation raw materials of the coal gangue-based matrix material preferably comprise, in mass fraction, coal gangue 40-50 parts, kaolin 2-6 parts, carboxymethyl cellulose 10-20 parts, cetyltrimethylammonium bromide 10-20 parts, a binder 5-10 parts, a surfactant 7-12 parts and polydiallyl phthalate 4-8 parts.
[0032] The preparation raw material provided by the present application preferably comprises 40-50 parts of coal gangue, and specifically can be 40 parts, 41 parts, 42 parts, 43 parts, 44 parts, 45 parts, 46 parts, 47 parts, 48 parts, 49 parts or 50 parts in terms of mass fraction. The preparation raw material provided by the present application preferably comprises 2-6 parts of kaolin in terms of mass fraction of the coal gangue, and specifically can be 2 parts, 3 parts, 4 parts, 5 parts or 6 parts. The preparation raw material provided by the present application preferably comprises 10-20 parts of carboxymethyl cellulose in terms of mass fraction of the coal gangue, and specifically can be 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts, 19 parts or 20 parts. The preparation raw material provided by the present application preferably comprises 10-20 parts of cetyltrimethylammonium bromide in terms of mass fraction of the coal gangue, and specifically can be 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts, 19 parts or 20 parts. The preparation raw material provided by the present application preferably comprises 5-10 parts of binder in terms of mass fraction of the coal gangue, and specifically can be 5 parts, 6 parts, 7 parts, 8 parts, 9 parts or 10 parts. The preparation raw material provided by the present application preferably comprises 7-12 parts of surfactant in terms of mass fraction of the coal gangue, and specifically can be 7 parts, 8 parts, 9 parts, 10 parts, 11 parts or 12 parts. The preparation raw material provided by the present application preferably comprises 4-8 parts of polydiallyl phthalate in terms of mass fraction of the coal gangue, and specifically can be 4 parts, 5 parts, 6 parts, 7 parts or 8 parts.
[0033] In the present application, the binder preferably comprises one or more of unsaturated polyester resin, phenolic resin, polyvinyl alcohol, alpha-cyanoacrylate, acrylate and epoxy resin.
[0034] In the present application, the surfactant preferably comprises one or more of sodium dodecyl sulfate and sodium dodecyl silicate. In the present application, the stability of the composite structure can be further improved by adding the surfactant and polydiallyl phthalate.
[0035] In the present application, the kaolin preferably comprises titanium mineral and organic matter, and the organic matter preferably comprises plant fiber. The content of the titanium mineral and the organic matter is not particularly limited in the present application, and can be determined by those skilled in the art.
[0036] In the present application, the particle size of the coal gangue is preferably 100-200 mesh, and further preferably 120-140 mesh.
[0037] In the present application, the porous material preferably comprises activated carbon, and the particle size of the porous material is preferably 100-200 mesh, and further preferably 120-140 mesh. The mass ratio of the coal gangue to the porous material is preferably 40-50:20-35.
[0038] In the present application, the coal gangue-based composite material is preferably a porous material, and the porosity of the coal gangue-based composite material is preferably 50-60%.
[0039] The present application also provides a preparation method of the coal gangue-based composite material as described in the above technical solution, which comprises the following steps:
[0040] The coal gangue is activated by hexadecyl trimethyl ammonium bromide to obtain activated coal gangue.
[0041] The activated coal gangue, kaolin, carboxymethyl cellulose, a binder and a porous material are mixed to obtain a mixture.
[0042] The mixture, a surfactant and a fixing agent are mixed, and then melt granulation is performed to obtain the coal gangue-based composite material.
[0043] In the present application, the temperature of the hot alkali activation is preferably 100-200℃, and the time is preferably 40-60 min.
[0044] After obtaining the activated coal gangue, the activated coal gangue, kaolin, carboxymethyl cellulose, a binder and a porous material are mixed to obtain a mixture.
[0045] In the present application, the mixing is preferably performed under stirring, and the stirring speed is preferably 200 rpm.
[0046] After obtaining the mixture, the mixture, a surfactant and polydiallyl phthalate are mixed, and then melt granulation is performed to obtain the coal gangue-based composite material.
[0047] In the present application, the temperature of the melt granulation is preferably 800-1000℃, and the holding time is preferably 1-2 h.
[0048] The present application also provides the application of the coal gangue-based composite material as described in the above technical solution or the coal gangue-based composite material prepared by the preparation method as described in the above technical solution in sewage treatment.
[0049] Unless otherwise specified, the materials and equipment used in the present application are commercially available in the art.
[0050] The technical solutions in the present application will be clearly and completely described below in combination with the embodiments in the present application. Apparently, the described embodiments are only some of the embodiments but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall into the scope of the present application.
[0051] Embodiment 1
[0052] Preparation:
[0053] The binder is polyvinyl alcohol, the surfactant is sodium dodecyl sulfate, the particle size of the coal gangue is 120-140 mesh, the porous material is activated carbon, and the particle size of the activated carbon is 120-140 mesh; the kaolin includes titanium minerals and plant fibers;
[0054] The preparation raw materials of the coal gangue matrix include, in mass fraction, coal gangue 40 parts, kaolin 2 parts, cetyltrimethylammonium bromide 20 parts, carboxymethyl cellulose 20 parts, polyvinyl alcohol 5 parts, sodium dodecyl sulfate 10 parts, and polydiallyl phthalate 5 parts;
[0055] The mass ratio of the coal gangue to the activated carbon is 40:20;
[0056] The coal gangue is activated by cetyltrimethylammonium bromide (CTAB) at 200℃ for 40 min to obtain activated coal gangue; the activated coal gangue, kaolin, activated carbon, hydroxymethyl cellulose, and polyvinyl alcohol are stirred and mixed at 200 rpm to obtain a mixture; the mixture is mixed with sodium dodecyl sulfate and polydiallyl phthalate, and then hot melt granulation is performed at 1000℃ for 1 h to obtain the coal gangue-based composite material, and the porosity is 55%.
[0057] Embodiment 2
[0058] Preparation:
[0059] The binder is polyvinyl alcohol, the surfactant is sodium dodecyl sulfate, the particle size of the coal gangue is 120-140 mesh, the porous material is activated carbon, and the particle size of the activated carbon is 120-140 mesh; the kaolin includes titanium minerals and plant fibers;
[0060] The preparation raw materials of the coal gangue matrix include, in mass fraction, coal gangue 40 parts, kaolin 2 parts, cetyltrimethylammonium bromide 20 parts, carboxymethyl cellulose 20 parts, polyvinyl alcohol 5 parts, sodium dodecyl sulfate 10 parts, and polydiallyl phthalate 5 parts;
[0061] The mass ratio of the coal gangue to the activated carbon is 45:25;
[0062] The coal gangue is activated by cetyltrimethylammonium bromide (CTAB) at 200℃ for 40min to obtain activated coal gangue; the activated coal gangue, kaolin, activated carbon, hydroxymethyl cellulose and polyvinyl alcohol are mixed by stirring at 200rpm to obtain a mixture; the mixture is mixed with sodium dodecyl sulfate and polyphenylene diallyl ester, and then hot melt granulation is performed at 1000℃ for 2h to obtain the coal gangue-based composite material, and the porosity is 57%.
[0063] Example 3
[0064] Preparation:
[0065] The binder is polyvinyl alcohol, the surfactant is sodium dodecyl sulfate, the particle size of the coal gangue is 120-140 mesh, the porous material is activated carbon, and the particle size of the activated carbon is 120-140 mesh; the kaolin includes titanium minerals and plant fibers;
[0066] The preparation raw materials of the coal gangue matrix include coal gangue 50 parts, kaolin 5 parts, cetyltrimethylammonium bromide 20 parts, carboxymethyl cellulose 20 parts, polyvinyl alcohol 10 parts, sodium dodecyl sulfate 12 parts and polyphenylene diallyl ester 8 parts by mass fraction;
[0067] The mass ratio of the coal gangue to the activated carbon is 50:30;
[0068] The coal gangue is activated by cetyltrimethylammonium bromide (CTAB) at 200℃ for 60min to obtain activated coal gangue; the activated coal gangue, kaolin, activated carbon, hydroxymethyl cellulose and polyvinyl alcohol are mixed by stirring at 200rpm to obtain a mixture; the mixture is mixed with sodium dodecyl sulfate and polyphenylene diallyl ester, and then hot melt granulation is performed at 800℃ for 1h to obtain the coal gangue-based composite material, and the porosity is 55%.
[0069] Application example
[0070] The enriched anaerobic sludge is placed in three upflow anaerobic sludge bed (UASB) reactors, and the coal gangue-based composite materials prepared in Examples 1-3 are added respectively. After biofilm formation, simulated wastewater containing 50mg / L nitrate is used as influent and is introduced into the reactor, and the hydraulic retention time is set to 3h. The UASB reactor is made of organic glass, with an inner diameter of 6cm, a height of 18cm, and an effective volume of about 0.5L. The three-phase separator at the upper part is embedded at an angle of 45° in the reactor, and is wrapped by an outer water bath layer. The water bath water is introduced from below and discharged from above. The reactor is kept warm by the outer water bath layer, and the temperature is controlled at 35±0.2℃.
[0071] Fig. 1Fig. 2 is a diagram showing the removal effect of pollutants by the coal gangue-based composite material obtained in Example 1, Fig. 2 Fig. 3 is a diagram showing the removal effect of pollutants by the coal gangue-based composite material obtained in Example 2, Fig. 3 Fig. 4 is a diagram showing the removal effect of pollutants by the coal gangue-based composite material obtained in Example 3;
[0072] The specific test results are shown in Table 1.
[0073] Table 1 Removal effect of pollutants by the coal gangue-based composite material obtained in Examples 1-3
[0074]
[0075] From Figs. 1-3 As can be seen from Table 1, the coal gangue-based composite material provided by the present application has superior denitrification effect.
[0076] Although the above examples have made a detailed description of the present application, it is only a part of the embodiments of the present application, but not all the embodiments, and other embodiments can be obtained according to the present embodiments without creativity, which all belong to the protection scope of the present application.
Claims
1. A method for preparing a coal gangue-based composite material, characterized in that, Includes the following steps: Coal gangue was activated by thermal alkaline activation using hexadecyltrimethylammonium bromide to obtain activated coal gangue. The activated coal gangue, kaolin, carboxymethyl cellulose, binder and porous material are mixed to obtain a mixture; The mixture, surfactant, and diallyl phthalate are mixed and then melt-granulated to obtain the coal gangue-based composite material. The hot alkali activation temperature is 100~200℃, and the time is 40~60min.
2. The preparation method according to claim 1, characterized in that, The melting and granulation temperature is 800~1000℃, and the holding time is 1~2h.
3. The coal gangue-based composite material prepared by the preparation method according to claim 1 or 2, characterized in that, Includes coal gangue matrix material and porous material loaded on the surface and in the pores of the coal gangue matrix material; The raw materials for preparing the coal gangue matrix material include coal gangue, kaolin, carboxymethyl cellulose, hexadecyltrimethylammonium bromide, binder, surfactant and diallyl phthalate.
4. The coal gangue-based composite material according to claim 3, characterized in that, The raw materials for preparing the coal gangue matrix material, by mass, include 40-50 parts of coal gangue, 2-6 parts of kaolin, 10-20 parts of carboxymethyl cellulose, 10-20 parts of hexadecyltrimethylammonium bromide, 5-10 parts of binder, 7-12 parts of surfactant, and 4-8 parts of diallyl phthalate.
5. The coal gangue-based composite material according to claim 3 or 4, characterized in that, The adhesive comprises one or more of unsaturated polyester resin, phenolic resin, polyvinyl alcohol, α-cyanoacrylate, acrylate and epoxy resin.
6. The coal gangue-based composite material according to claim 3 or 4, characterized in that, The surfactant includes one or more of sodium dodecyl sulfate and sodium dodecyl silicate.
7. The coal gangue-based composite material according to claim 3 or 4, characterized in that, The particle size of the coal gangue is 100-200 mesh; The porous material includes activated carbon; The porous material has a particle size of 100-200 mesh; the mass ratio of coal gangue to porous material is 40-50:20-35.
8. The coal gangue-based composite material according to claim 3 or 4, characterized in that, The coal gangue-based composite material is a porous material with a porosity of 50-60%.
9. The application of the coal gangue-based composite material according to any one of claims 3 to 8 in wastewater treatment.