A renewable adsorption material for sewage treatment and preparation method thereof

Abstract

The present invention belongs to the technical field of sewage treatment, and in particular relates to a renewable adsorption material for sewage treatment and a preparation method thereof. The material comprises the following raw materials in parts by weight: 70-120 parts of aggregate; 20-50 parts of flux; 10-20 parts of pore-forming agent; 3-10 parts of binder; and 30-90 parts of plastic particles. The renewable adsorption material for sewage treatment according to the present invention has the advantages of a wide source of raw materials, low preparation cost, high mechanical strength, high specific surface area, good adsorption performance, and is renewable.

Description

Technical Field

[0001] The present invention belongs to the technical field of sewage treatment, and in particular relates to a renewable adsorption material for sewage treatment and a preparation method thereof. Background Art

[0002] With the development of modern society, the discharge of industrial and domestic sewage is increasing, and the pollutants contained in the sewage are also increasing. Among them, organic pollutants have great harm to the environment and human health. The sewage must be deeply purified before discharge to avoid environmental pollution.

[0003] Currently, there are many methods for treating organically polluted wastewater, such as the common biological method, physical method, chemical method, etc. Among them, the biological method is a method that uses the metabolic activity of microorganisms to decompose organic pollutants in wastewater, mainly including aerobic biological treatment, anaerobic biological treatment, biochemical method, bioadsorption method, bioflocculation method, etc.; the microorganisms that play a key role in the biological method are very susceptible to toxic and harmful organic pollutants, resulting in wastewater treatment failing to meet satisfactory standards. Therefore, the operation and management process is relatively complex and requires professional technicians to conduct continuous monitoring and maintenance. If poorly managed or improperly operated, it may lead to a decline in treatment effect or system crash, and the application is more difficult. The chemical method is a method of oxidation treatment using chemical reagents, and there are also treatments through precipitation technology. Chemical methods usually require the introduction of new chemical agents. It is often difficult to avoid the formation of new chemical pollution during the generation of these chemical agents, and the price of chemical agents is usually relatively expensive. Physical treatment methods are methods that remove or transform organic matter from wastewater through physical means. Common methods include adsorption and membrane separation technology. Adsorption uses porous solid adsorbents to absorb one or more pollutants in wastewater to recover or remove these pollutants, thereby purifying the wastewater. Adsorption has the advantages of good treatment results, high effluent quality, stable operation, simple operation, convenient management, simple process, and a wide range of applications. It is currently one of the most widely used water treatment technologies. However, adsorption also has the drawbacks of high adsorbent costs, difficulty in regeneration, and the need to properly dispose of pollutants adsorbed by the adsorbent, otherwise secondary pollution may occur.

[0004] To reduce the manufacturing cost of porous adsorbents for wastewater treatment by adsorption, those skilled in the art have attempted various approaches. For example, Chinese patents with publication (announcement) numbers CN112979275B and CN112279243B utilize low-cost materials or industrial waste, such as sludge, waste incineration ash, blast furnace slag, steel slag, river sand, waste glass, and coal gangue, to produce porous adsorbents with excellent adsorption properties. Among these, the carbonization of sludge is a method for preparing porous adsorbents that not only treats sludge and reduces sludge storage and transportation costs, but also produces solid carbides with stable biological and chemical properties. Sludge carbides are primarily composed of elements such as carbon, hydrogen, oxygen, and nitrogen, as well as minerals such as aluminum, iron, potassium, sodium, magnesium, and calcium. They possess a rich microporous structure, a large specific surface area, and excellent adsorption properties. They are also highly permeable to water and air, and exhibit excellent adsorption properties for heavy metal ions and organic pollutants. Sludge carbides are currently widely used as porous adsorbents for wastewater and exhaust gas treatment. However, the source of fixed carbon in sludge carbonization is the thermal decomposition of organic matter in the sludge. In addition to organic matter, sludge also contains a large amount of non-carbonizable inorganic matter, heavy metal ions, soil and other components, which leads to the specific surface area and adsorption performance of sludge carbonization being significantly worse than those of activated carbon. In addition, the strength of sludge carbonization is low, and sludge carbonization is easily broken and pulverized under long-term erosion of water flow, which is also one of the factors limiting its circulation and application.

[0005] In this context, finding new, more cost-effective porous adsorbents for sewage treatment has become one of the long-term research directions of those skilled in the art. We found that: currently, people's consumption of plastic products remains high. For example, China's production and consumption of plastic products are among the highest in the world, but the recycling rate of plastic waste is generally low worldwide. A large amount of plastic waste is not effectively recycled and reused, but is landfilled or incinerated. If plastic waste can be used to prepare porous adsorbents for sewage treatment, then while achieving plastic waste treatment, it can also reduce the preparation cost of porous adsorbents, providing a new method for the preparation of porous adsorbents.

[0006] In view of this, the present invention provides an adsorption material for sewage treatment based on waste plastics, which has low preparation cost, good adsorption effect, high mechanical strength, is not prone to secondary pollution, and is renewable. Summary of the Invention

[0007] The purpose of the present invention is to provide a new type of renewable adsorption material for sewage treatment in order to solve the above-mentioned technical problems.

[0008] In view of this, the present invention provides a method for preparing a renewable adsorption material for sewage treatment, wherein the renewable adsorption material for sewage treatment comprises the following raw materials in parts by weight:

[0009] 70~120 parts of aggregate;

[0010] 20~50 parts of flux;

[0011] 10-20 parts of pore-forming agent;

[0012] 3~10 parts of adhesive;

[0013] 30~90 parts of plastic particles.

[0014] Furthermore, the renewable adsorption material for sewage treatment further comprises 3 to 15 parts by weight of reinforcing fibers, and the refractory temperature of the reinforcing fibers is ≥1100°C.

[0015] Furthermore, the aggregate includes inorganic particles of three sizes: large, medium and small, wherein the average particle size of the large-size inorganic particles is 0.5~1mm, the average particle size of the medium-size inorganic particles is 100~300um, and the average particle size of the small-size inorganic particles is <100um. The aggregate is a mixture of natural inorganic minerals and industrial inorganic solid waste, wherein the industrial inorganic solid waste accounts for 20~40wt% of the total aggregate.

[0016] Furthermore, the binder is an inorganic sol, and the solid content of the inorganic sol is 5-20 wt%.

[0017] Furthermore, the particle size of the plastic particles is 0.5-1 mm, and the plastic particles are selected from one or more of polyethylene, polypropylene, and polystyrene.

[0018] Furthermore, the method for preparing the regenerable adsorption material for sewage treatment comprises the steps of:

[0019] S1, prepare aggregate:

[0020] (1) First, the natural inorganic mineral particles and industrial inorganic solid waste particles are screened to obtain natural inorganic mineral particles and industrial inorganic solid waste particles with an average particle size of 0.5-1 mm, natural inorganic mineral particles and industrial inorganic solid waste particles with an average particle size of 100-300 μm, and natural inorganic mineral particles and industrial inorganic solid waste particles with an average particle size of less than 100 μm;

[0021] (2) Then, according to the weight ratio of large, medium and small inorganic particles in the aggregate, natural inorganic mineral particles or industrial inorganic solid waste particles of corresponding particle sizes are selected to prepare the aggregate, wherein the aggregate is a mixture of natural inorganic minerals and industrial inorganic solid waste, and the industrial inorganic solid waste accounts for 20-40wt% of the total aggregate;

[0022] (3) The selected industrial inorganic solid waste particles are then dispersed in an alkaline solution, and after sufficient stirring, an alkaline suspension of the industrial inorganic solid waste particles is obtained. The suspension is heated to 50-90°C, kept warm and soaked for 1-3 hours, filtered, and dried to obtain pretreated industrial inorganic solid waste particles;

[0023] (4) Mixing and stirring the pretreated industrial inorganic solid waste particles and natural inorganic mineral particles to obtain aggregate;

[0024] S2, uniformly mixing the aggregate prepared in step S1 with the formulated amount of flux, pore former and binder to obtain mixture I;

[0025] S3, uniformly mixing the formulated amount of plastic particles with mixture I to obtain mixture II;

[0026] S4, shaping the mixture II to obtain a profile III;

[0027] S5, placing the profile III in a high-temperature carbonization furnace for calcination and carbonization, and then naturally cooling to room temperature to obtain the carbonized profile IV, which is the renewable adsorption material for sewage treatment.

[0028] Furthermore, in step S5, a staged carbonization process or a one-stage carbonization process is used to perform high-temperature carbonization treatment on the profile III:

[0029] Among them, the segmented carbonization process is:

[0030] (1) Pre-oxidation treatment: First, place the profile III in a high-temperature furnace at 300~500℃ under air atmosphere for pre-oxidation treatment. The pre-oxidation treatment time is 20~60min.

[0031] (2) Carbonization treatment: placing the pre-oxidized profile III in a high-temperature carbonization furnace, calcining and carbonizing it at 600-1000°C for 2-4 hours under the protection of an inert atmosphere, and then naturally cooling it to room temperature to obtain the renewable adsorption material for sewage treatment;

[0032] The one-stage carbonization process is as follows: placing the profile III in a high-temperature carbonization furnace, calcining and carbonizing it at 600-1000° C. for 3-5 hours under the protection of an inert atmosphere, and then naturally cooling it to room temperature to obtain the renewable adsorption material for sewage treatment.

[0033] Furthermore, after obtaining the adsorption material in step S5, the adsorption material obtained in step S5 is post-processed by a physical activation or plasma etching process, wherein:

[0034] The physical activation process is as follows: first, the carbonized profile IV is placed in an argon atmosphere furnace, and then water vapor is loaded into the atmosphere furnace through argon gas as an activating agent, wherein the total flow rate of argon gas and water vapor is 50-80 mL / min, and the volume ratio of argon gas to water vapor is 1:(1.2-1.8); and the furnace temperature in the atmosphere furnace is raised to 500-800°C at a rate of 5-10°C / min, and then kept at this temperature for 0.5-1.5 hours. After natural cooling, the regenerable adsorption material for wastewater treatment after post-treatment is obtained;

[0035] The plasma etching process is as follows: using hydrogen fluoride as the etching gas, the renewable adsorption material for sewage treatment is subjected to plasma etching at an etching pressure of 40-60 Pa, a gas flow rate of 40-80 sccm, and a power of 50-60 W. During the plasma etching process, it should be ensured that the surface of the adsorption material is evenly exposed to the plasma. The etching time is 20-60 minutes. After the etching is completed, the adsorption material is washed with water and dried at a low temperature of 40-80° C. to obtain the renewable adsorption material for sewage treatment after post-treatment.

[0036] Furthermore, the regeneration process of the regenerable adsorbent material for sewage treatment comprises the following steps:

[0037] P1, placing the adsorption saturated adsorption material in a high-temperature carbonization furnace, calcining and carbonizing at 600~1000℃ for 1~2h under argon atmosphere protection;

[0038] P2, then water vapor is loaded into the atmosphere furnace as an activating agent through argon gas, wherein the total flow rate of argon gas and water vapor is 30~50mL / min, and the volume ratio of argon gas to water vapor is 1:(1.2~1.8); and the furnace temperature in the atmosphere furnace is raised to 500~800℃ at a rate of 10~15℃ / min, kept warm for 10~30min, and naturally cooled to obtain the regenerated adsorption material.

[0039] A renewable adsorption material for sewage treatment is provided, wherein the renewable adsorption material for sewage treatment is the adsorption material prepared by the above-mentioned preparation method.

[0040] The beneficial effects of the present invention are:

[0041] The renewable adsorption material for sewage treatment of the present invention has the advantages of wide raw material sources, low preparation cost, high mechanical strength, high specific surface area, good adsorption performance, and renewability. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 This is a flow chart for preparing the regenerable adsorption material for sewage treatment according to the present invention;

[0043] Figure 2This is a cross-sectional view of the regenerable adsorption material for sewage treatment prepared by the present invention;

[0044] Figure 3 This is a graph showing the changing trend of the adsorption performance of the regenerable adsorption material for sewage treatment according to the present invention as a function of the number of regenerations. DETAILED DESCRIPTION

[0045] The following will be combined with the accompanying drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of this application.

[0046] It should be noted that, in the present application, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element. In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in the opposite order according to the functions involved. For example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0047] A method for preparing a renewable adsorption material for sewage treatment, wherein the renewable adsorption material for sewage treatment comprises the following raw materials in parts by weight:

[0048] 70~120 parts of aggregate;

[0049] 20~50 parts of flux;

[0050] 10-20 parts of pore-forming agent;

[0051] 3~10 parts of adhesive;

[0052] 30~90 parts of plastic particles.

[0053] Furthermore, the renewable adsorption material for sewage treatment further comprises 3 to 15 parts by weight of reinforcing fibers.

[0054] Preferably, the reinforcing fiber is a high temperature resistant fiber, and the fire resistant temperature of the reinforcing fiber is ≥1100°C.

[0055] As some examples of the present invention, the reinforcing fiber is selected from one or more of asbestos fiber, aluminum silicate fiber, zirconium dioxide fiber, mullite refractory fiber, silicon carbide fiber, and the like.

[0056] The addition of these reinforcing fibers improves the skeleton structure of the resulting renewable adsorbent material for wastewater treatment, helping to create more open pores, increasing its porosity, structural strength, and toughness, thereby increasing its regeneration and recycling capabilities. Furthermore, the addition of these reinforcing fibers acts as a bridge for stress conduction during high-temperature treatment, reducing internal stress accumulation and preventing cracking caused by stress accumulation due to temperature gradients during high-temperature treatment.

[0057] Preferably, the aggregate includes inorganic particles of large, medium and small particle sizes, wherein the average particle size of the large-sized inorganic particles is 0.5-1 mm, the average particle size of the medium-sized inorganic particles is 100-300 μm, and the average particle size of the small-sized inorganic particles is <100 μm.

[0058] More preferably, in the aggregate, the weight ratio of the large-size inorganic particles, the medium-size inorganic particles and the small-size inorganic particles is (1-3): (4-6): (2-3).

[0059] In the present invention, inorganic particles with large, medium and small particle sizes are used as aggregates. The large-size inorganic particles can form the skeleton of the adsorption material, ensure the mechanical strength of the adsorption material, and provide a larger flow channel for the fluid, which is conducive to the rapid diffusion and transmission of substances; the medium-size inorganic particles mainly play a connecting role, filling the gaps between the large-size inorganic particles, improving the strength of the adsorption material, and maintaining a certain porosity; the small-size inorganic particles are filled in the pores, mainly playing the role of increasing the specific surface area, providing more adsorption sites, and improving the adsorption efficiency. In this way, through the compounding of large, medium and small-size inorganic particles, the pore size distribution can be optimized, which helps to form a multi-level pore structure with good connectivity. This is beneficial to the rapid transmission of substances and provides a large number of adsorption sites, thereby improving the permeability, selectivity, adsorption capacity and adsorption efficiency of the adsorbent.

[0060] As some examples of the present invention, the aggregate is selected from one or more natural inorganic minerals such as mica, potassium feldspar, sodium feldspar, quartz sand, talc, wollastonite, and river sand. Furthermore, the aggregate can also be selected from one or more industrial inorganic solid wastes such as blast furnace slag, steel slag, coal gangue, and fly ash.

[0061] Preferably, the aggregate is a mixture of natural inorganic minerals and industrial inorganic solid waste, wherein the industrial inorganic solid waste accounts for 20-40 wt% of the total aggregate.

[0062] As some examples of the present invention, the flux is selected from one or more of potassium oxide, magnesium oxide, calcium oxide, barium oxide, boron oxide, aluminum oxide, zinc oxide, calcium fluoride, magnesium fluoride, sodium borate, potassium borate, zinc borate, low-melting-point glass powder, etc.

[0063] Preferably, the melting temperature of the flux is 300-1000°C.

[0064] More preferably, the melting temperature of the flux is 350-500°C.

[0065] Preferably, the pore-forming agent is an inorganic pore-forming agent.

[0066] As some examples of the present invention, the pore-forming agent is selected from one or more of calcium carbonate, ammonium carbonate, ammonium bicarbonate, ammonium chloride, and the like.

[0067] Preferably, the binder is an inorganic sol.

[0068] More preferably, the solid content of the inorganic sol is 5-20 wt %.

[0069] As some examples of the present invention, the binder is selected from one or more of silica sol, alumina sol, and zirconia sol.

[0070] On the basis of the reinforcing fibers, the addition of the binder can further improve the mechanical strength and durability of the adsorption material.

[0071] Preferably, the average particle size of the plastic particles is 0.5-1 mm, that is, the particle size of the plastic particles should be equivalent to the average particle size of the large-sized inorganic particles in the aggregate. If the particle size of the plastic particles is too small, the volume of the carbon material phase formed after carbonization is too small and it is easy to fall out of the matrix.

[0072] Preferably, the plastic particles are particles of waste plastic.

[0073] Preferably, the melting temperature of the plastic particles is 100-300°C.

[0074] As some examples of the present invention, the plastic particles are selected from polyethylene (PE), polypropylene (PP), polystyrene (PS), etc. These types of plastics are relatively common, easy to collect, do not contain metal ions, have high carbon content, and deposit a large amount of residual carbon after calcination, which is more conducive to forming the carbide phase in the renewable adsorbent material for sewage treatment described in the present invention.

[0075] Waste plastics scattered throughout society pose a significant threat to the environment, posing a fire hazard, soil pollution, pollution of water bodies such as oceans and rivers, and human health risks, severely damaging the living environment. In this invention, waste plastics are used to prepare renewable adsorbent materials for sewage treatment. This not only recycles and utilizes waste plastics, providing a new method for waste plastic reuse and saving the environment, but also reduces the cost of preparing the adsorbent material, thereby reducing sewage treatment costs, while also comprehensively utilizing resources.

[0076] Further, such as Figure 1 As shown, the method for preparing the renewable adsorption material for sewage treatment according to the present invention comprises the following steps:

[0077] S1, prepare aggregate:

[0078] (1) First, the natural inorganic mineral particles and industrial inorganic solid waste particles are screened to obtain natural inorganic mineral particles and industrial inorganic solid waste particles with an average particle size of 0.5-1 mm, natural inorganic mineral particles and industrial inorganic solid waste particles with an average particle size of 100-300 μm, and natural inorganic mineral particles and industrial inorganic solid waste particles with an average particle size of less than 100 μm;

[0079] (2) Then, according to the weight ratio of large, medium and small inorganic particles in the aggregate, natural inorganic mineral particles or industrial inorganic solid waste particles of corresponding particle sizes are selected to prepare the aggregate, wherein the aggregate is a mixture of natural inorganic minerals and industrial inorganic solid waste, and the industrial inorganic solid waste accounts for 20-40wt% of the total aggregate;

[0080] (3) The selected industrial inorganic solid waste particles are then dispersed in an alkaline solution, and after sufficient stirring, an alkaline suspension of the industrial inorganic solid waste particles is obtained. The suspension is heated to 50-90°C, kept warm and soaked for 1-3 hours, filtered, and dried to obtain pretreated industrial inorganic solid waste particles;

[0081] (4) Mixing and stirring the pretreated industrial inorganic solid waste particles and natural inorganic mineral particles to obtain aggregate;

[0082] S2, uniformly mixing the aggregate prepared in step S1 with the formulated amount of flux, pore former and binder to obtain mixture I;

[0083] S3, uniformly mixing the formulated amount of plastic particles with mixture I to obtain mixture II;

[0084] S4, shaping the mixture II to obtain a profile III;

[0085] S5, placing the profile III in a high-temperature carbonization furnace for calcination and carbonization, and then naturally cooling to room temperature to obtain the carbonized profile IV, which is the renewable adsorption material for sewage treatment.

[0086] As some examples of the present invention, when only natural inorganic mineral particles are used as aggregate, the aggregate can be directly mixed with the flux, pore former and binder in step S2 to obtain mixture I.

[0087] It should be noted that for general adsorption materials, during the preparation of the aggregate, there is no specific limitation on the weight proportion of industrial inorganic solid waste in inorganic particles of large, medium and small particle sizes. It can be configured according to needs, and it is only necessary to ensure that the proportion of industrial inorganic solid waste in the total amount of aggregate meets the requirements.

[0088] However, in sewage treatment environments with high sewage flow rates, severe scouring, and higher requirements for adsorption material strength, it is preferred that the weight proportion of industrial inorganic solid waste in inorganic particles of large, medium, and small particle sizes be set to increase in sequence, such as the weight proportion of industrial inorganic solid waste in inorganic particles of large particle size is 15wt%, the weight proportion of industrial inorganic solid waste in inorganic particles of medium particle size is 25wt%, and the weight proportion of industrial inorganic solid waste in inorganic particles of small particle size is 35wt%.

[0089] In the preparation process of the adsorption material described in the present invention, by placing industrial inorganic solid waste in an alkaline solution for heating and soaking treatment, the surface structure of the industrial inorganic solid waste formed during the earlier high-temperature treatment process can be corroded and destroyed. On the one hand, the activity of soluble silica, alumina and other components inside the industrial inorganic solid waste can be released, and it is easy to combine with other components in the adsorption material, such as calcium oxide, during the subsequent high-temperature treatment process, thereby promoting the binding force between different aggregate particles, aggregate particles and flux, and aggregate particles and carbon material phases, thereby greatly improving the strength of the final adsorption material.

[0090] Preferably, in step S1, the alkaline solution is one or more strongly alkaline solutions such as sodium hydroxide solution and potassium hydroxide solution.

[0091] Preferably, in step S1, the concentration of the alkaline solution is 5-15 wt%.

[0092] Preferably, in step S1, the amount of the alkaline solution used is 1.5 to 3 times the weight of the industrial inorganic solid waste.

[0093] Preferably, in step S3, the plastic particles and mixture I can be mixed using a screw extruder, kneader, internal mixer, or the like. The mixing time is 5 to 15 minutes, and the mixing temperature is determined based on the plasticizing temperature of the plastic particles. Specifically, the mixing temperature is preferably equal to or slightly higher than the plasticizing temperature of the plastic particles. For example, the mixing temperature can be 130-280°C. It should be noted that, generally, the mixing temperature should not exceed 300°C to prevent decomposition of the melt.

[0094] As some examples of the present invention, in step S4, a plastic tool such as an injection molding machine or a flat-plate vulcanizing machine may be used to shape the mixture II to obtain the profile III.

[0095] Furthermore, in step S5, a staged carbonization process or a one-stage carbonization process may be used to perform high-temperature carbonization treatment on the profile III. Specifically:

[0096] The segmented carbonization process is:

[0097] (1) Pre-oxidation treatment: First, place the profile III in a high-temperature furnace at 300~500℃ under air atmosphere for pre-oxidation treatment. The pre-oxidation treatment time is 20~60min.

[0098] (2) Carbonization treatment: The pre-oxidized profile III is placed in a high-temperature carbonization furnace, and calcined and carbonized at 600-1000°C for 2-4 hours under the protection of an inert atmosphere, and then naturally cooled to room temperature to obtain the renewable adsorption material for sewage treatment.

[0099] One-stage carbonization process: placing profile III in a high-temperature carbonization furnace, calcining and carbonizing at 600-1000° C. for 3-5 hours under inert atmosphere, and then naturally cooling to room temperature to obtain the renewable adsorption material for sewage treatment.

[0100] As some examples of the present invention, the carbonization process can be performed under the protection of an inert atmosphere such as argon or helium.

[0101] In addition, in the present invention, after the adsorption material is obtained through the step S5, although the carbon material phase in the adsorption material has a simple pore structure, the pore size and specific surface area are not excellent enough. At this time, the adsorption material obtained in step S5 can be further post-processed by physical activation, plasma etching process, etc. after calcination and carbonization treatment.

[0102] As some examples of the present invention, physical activation can use water vapor as an activating agent to activate the carbonized profile IV at high temperature. The specific process is as follows:

[0103] First, the carbonized profile IV is placed in an argon atmosphere furnace, and then water vapor is loaded into the atmosphere furnace through argon as an activating agent, wherein the total flow rate of argon and water vapor is 50~80mL / min, and the volume ratio of argon to water vapor is 1:(1.2~1.8); and the furnace temperature in the atmosphere furnace is increased to 500~800℃ at a rate of 5~10℃ / min, and then kept warm for 0.5~1.5h. After natural cooling, the regenerable adsorption material for sewage treatment after post-treatment is obtained.

[0104] As some examples of the present invention, the plasma etching process is as follows: hydrogen fluoride is used as the etching gas, and the renewable adsorption material for sewage treatment is subjected to plasma etching at an etching pressure of 40~60Pa, a gas flow rate of 40~80sccm, and a power of 50~60W. During the plasma etching process, it should be ensured that the surface of the adsorption material is evenly exposed to the plasma, and the etching time is 20~60min. After the etching is completed, the adsorption material is washed with water and dried at a low temperature of 40~80°C to obtain the renewable adsorption material for sewage treatment after post-treatment.

[0105] The color of the regenerable adsorption material for sewage treatment obtained by the invention is gray, black profile or granular matter.

[0106] As some examples of the present invention, the dosage of the renewable adsorption material for sewage treatment obtained by the present invention in the polluted water body is 1-10 g / L, which can be adjusted according to the content of pollutants in the sewage.

[0107] The preparation principle of the renewable adsorption material for sewage treatment according to the present invention is as follows:

[0108] Flux, binder and reinforcing fiber are used to bond the natural mineral powder and industrial inorganic solid waste powder in the material into a ceramic substrate at high temperature. At the same time, since the raw materials contain pore-forming agents, a large number of pores will be formed in the material during the high-temperature melting, plasticizing and molding process. Furthermore, under subsequent high-temperature calcination, the plastic particles are carbonized to form the carbon material phase in the adsorption material, which is dispersed in the ceramic substrate. The pore size and specific surface area of ​​the carbon material phase are further optimized through subsequent activation treatment, and finally a composite structure in which the porous ceramic substrate and the carbon material phase are staggered is formed. In this composite structure, the pores in the porous ceramic substrate can provide low-resistance channels for the flow of fluid, and the carbon material phase therein can provide favorable conditions for the adsorption of pollutants in the fluid, effectively combining small-pore filtration and adsorption and impurity removal to achieve efficient sewage treatment.

[0109] Compared with traditional methods of preparing adsorption materials by carbonizing sludge, bio-organic matter, and composite with ceramic substrates, the carbon material obtained after plastic carbonization is harder, more wear-resistant, and resistant to fluid erosion, so it has better mechanical properties and stability. It is also more stable in combination with the ceramic substrate and is not easy to escape from the pores of the adsorption material. The resulting adsorption material has higher strength and can be recycled more times.

[0110] In addition, the present invention also provides a method for regenerating the above-mentioned regenerable adsorbent material for sewage treatment, comprising the steps of:

[0111] P1, placing the adsorption saturated adsorption material in a high-temperature furnace, calcining and carbonizing it at 600~1000℃ for 1~2h under argon atmosphere;

[0112] P2, then water vapor is loaded into the atmosphere furnace as an activating agent through argon gas, wherein the total flow rate of argon gas and water vapor is 30~50mL / min, and the volume ratio of argon gas to water vapor is 1:(1.2~1.8); and the furnace temperature in the atmosphere furnace is raised to 500~800℃ at a rate of 10~15℃ / min, kept warm for 10~30min, and naturally cooled to obtain the regenerated adsorption material.

[0113] Preferably, after the regenerated adsorption material is obtained by calcination, the ash released from the adsorption material can be removed by shaking or the like.

[0114] On the basis of the adsorption material provided by the present invention, in order to improve the water treatment effect, those skilled in the art may also choose to load and set chemical agents such as photocatalysts on the adsorption material provided by the present invention to degrade pollutants in sewage through chemical reactions, so as to achieve the synergistic treatment effect of physical adsorption and chemical catalytic degradation.

[0115] The following specific examples illustrate the renewable adsorption material for sewage treatment and the preparation method thereof according to the present invention:

[0116] Example 1

[0117] Preparation of renewable adsorption materials for sewage treatment:

[0118] The raw materials used include: 70 parts by weight of aggregate, 20 parts by weight of flux, 10 parts by weight of pore-forming agent, 3 parts by weight of binder, and 30 parts of plastic particles. The aggregate is a natural inorganic mineral with an average particle size of 250 μm, the flux is a mixture of calcium oxide and low-melting-point glass powder, the pore-forming agent is ammonium carbonate, the binder is a silica sol with a solid content of 20 wt%, and the plastic particles are a mixture of PE and PP.

[0119] The preparation process of renewable adsorption materials for sewage treatment is as follows:

[0120] The aggregate is directly mixed with the formulated amount of flux, pore former and binder to obtain mixture I;

[0121] Then, the plastic particles in the formulated amount are uniformly mixed with the mixture I to obtain a mixture II;

[0122] The mixture II is molded to obtain a profile III;

[0123] The profile III is placed in a high-temperature carbonization furnace, calcined and carbonized at 600° C. for 5 hours under the protection of an inert atmosphere, and then naturally cooled to room temperature to obtain the renewable adsorption material for sewage treatment.

[0124] Example 2

[0125] Preparation of renewable adsorption materials for sewage treatment:

[0126] The raw materials used include: 70 parts by weight of aggregate, 20 parts by weight of flux, 10 parts by weight of pore-forming agent, 3 parts by weight of binder, and 30 parts of plastic particles. The aggregate includes natural inorganic minerals with an average particle size of 1 mm, natural inorganic mineral particles with an average particle size of 200 μm, and natural inorganic mineral particles with an average particle size of 40 μm. The weight ratio of large-particle aggregate, medium-particle aggregate, and small-particle aggregate is 1:5:3. The flux is a mixture of calcium oxide and low-melting-point glass powder, the pore-forming agent is ammonium carbonate, the binder is silica sol with a solid content of 20 wt%, and the plastic particles are a mixture of PE and PP.

[0127] The preparation process of the regenerable adsorbent material for sewage treatment is the same as that in Example 1.

[0128] Example 3

[0129] Preparation of renewable adsorption materials for sewage treatment:

[0130] The raw materials used include: 100 parts by weight of aggregate, 30 parts by weight of flux, 20 parts by weight of pore-forming agent, 8 parts by weight of binder, and 60 parts of plastic particles. The aggregate includes natural inorganic minerals with an average particle size of 1 mm, natural inorganic mineral particles with an average particle size of 200 μm, and natural inorganic mineral particles with an average particle size of 40 μm. The weight ratio of large-particle aggregate, medium-particle aggregate, and small-particle aggregate is 2:5:2. The flux is a mixture of magnesium oxide, calcium oxide, potassium borate, and low-melting-point glass powder. The pore-forming agent is a mixture of ammonium carbonate and ammonium chloride. The binder is silica sol with a solid content of 15 wt%. The plastic particles are PE.

[0131] The preparation process of renewable adsorption materials for sewage treatment is as follows:

[0132] The aggregate is directly mixed with the formulated amount of flux, pore former and binder to obtain mixture I;

[0133] Then, the plastic particles in the formulated amount are uniformly mixed with the mixture I to obtain a mixture II;

[0134] The mixture II is molded to obtain a profile III;

[0135] The profile III is placed in a high-temperature carbonization furnace, calcined and carbonized at 800° C. for 4 hours under the protection of an inert atmosphere, and then naturally cooled to room temperature to obtain the renewable adsorption material for sewage treatment.

[0136] Example 4

[0137] Preparation of renewable adsorption materials for sewage treatment:

[0138] The raw materials used include: 100 parts by weight of aggregate, 30 parts by weight of flux, 20 parts by weight of pore-forming agent, 8 parts by weight of binder, and 60 parts of plastic particles. The aggregate includes a mixture of natural inorganic minerals with an average particle size of 1 mm and industrial inorganic solid waste, a mixture of natural inorganic mineral particles with an average particle size of 200 μm and industrial inorganic solid waste, and a mixture of natural inorganic mineral particles with an average particle size of 40 μm and industrial inorganic solid waste. The weight ratio of large-particle aggregate, medium-particle aggregate, and small-particle aggregate is 2:5:2, and the industrial inorganic solid waste accounts for 30% by weight of the total aggregate. The flux is a mixture of magnesium oxide, calcium oxide, potassium borate, and low-melting-point glass powder. The pore-forming agent is a mixture of ammonium carbonate and ammonium chloride. The binder is silica sol with a solid content of 15% by weight. The plastic particles are PE.

[0139] The preparation process of renewable adsorption materials for sewage treatment is as follows:

[0140] The selected industrial inorganic solid waste particles are dispersed in a 10wt% sodium hydroxide solution, where the amount of the sodium hydroxide solution added is twice the weight of the industrial inorganic solid waste particles. After sufficient stirring, an alkaline suspension of the industrial inorganic solid waste particles is obtained. The suspension is heated to 80°C, kept warm and soaked for 2 hours, filtered, and dried to obtain pretreated industrial inorganic solid waste particles.

[0141] The pretreated industrial inorganic solid waste particles and natural inorganic mineral particles are mixed and stirred to obtain aggregate;

[0142] The aggregate is uniformly mixed with the flux, pore former and binder in the prescribed amount to obtain mixture I;

[0143] Then, the plastic particles in the formulated amount are uniformly mixed with the mixture I to obtain a mixture II;

[0144] The mixture II is molded to obtain a profile III;

[0145] The profile III is placed in a high-temperature carbonization furnace, calcined and carbonized at 800° C. for 4 hours under the protection of an inert atmosphere, and then naturally cooled to room temperature to obtain the renewable adsorption material for sewage treatment.

[0146] Example 5

[0147] The only difference between this embodiment and the above-mentioned embodiment 4 is that the raw materials used to prepare the regenerable adsorption material further include 5 parts by weight of mullite refractory fiber.

[0148] Example 6

[0149] Preparation of renewable adsorption materials for sewage treatment:

[0150] The raw materials used include: 120 parts by weight of aggregate, 50 parts by weight of flux, 15 parts by weight of pore-forming agent, 10 parts by weight of binder, and 90 parts of plastic particles. The aggregate includes a mixture of natural inorganic minerals with an average particle size of 0.8 mm and industrial inorganic solid waste, a mixture of natural inorganic mineral particles with an average particle size of 300 μm and industrial inorganic solid waste, and a mixture of natural inorganic mineral particles with an average particle size of 30 μm and industrial inorganic solid waste. The weight ratio of large-particle aggregate, medium-particle aggregate, and small-particle aggregate is 3:6:3, and the industrial inorganic solid waste accounts for 40% by weight of the total aggregate. The flux is a mixture of magnesium oxide and low-melting-point glass powder, the pore-forming agent is a mixture of ammonium carbonate and calcium carbonate, the binder is alumina sol with a solid content of 5% by weight, and the plastic particles are a mixture of PE and PS.

[0151] The preparation process of renewable adsorption materials for sewage treatment is as follows:

[0152] The selected industrial inorganic solid waste particles are dispersed in a 15wt% sodium hydroxide solution, where the amount of the sodium hydroxide solution added is 1.5 times the weight of the industrial inorganic solid waste particles. After sufficient stirring, an alkaline suspension of the industrial inorganic solid waste particles is obtained. The suspension is heated to 90°C, kept warm and soaked for 3 hours, filtered, and dried to obtain pretreated industrial inorganic solid waste particles.

[0153] The pretreated industrial inorganic solid waste particles and natural inorganic mineral particles are mixed and stirred to obtain aggregate;

[0154] The aggregate is uniformly mixed with the flux, pore former and binder in the prescribed amount to obtain mixture I;

[0155] Then, the plastic particles in the formulated amount are uniformly mixed with the mixture I to obtain a mixture II;

[0156] The mixture II is molded to obtain a profile III;

[0157] Then, the profile III is placed in a high-temperature furnace at 400°C for pre-oxidation in an air atmosphere for 50 minutes. The pre-oxidation profile III is then placed in a high-temperature carbonization furnace and calcined and carbonized at 800°C for 3 hours under inert atmosphere. The profile is then naturally cooled to room temperature to obtain the renewable adsorption material for sewage treatment. After the adsorption material is cut open, the cross-sectional morphology of the interior thereof is as follows: Figure 2 shown.

[0158] Example 7

[0159] The only difference between it and the above-mentioned Example 6 is that the profile III is subjected to high-temperature carbonization treatment using the one-stage carbonization process shown below: the profile III is placed in a high-temperature carbonization furnace, calcined and carbonized at 800°C for 4 hours under the protection of an inert atmosphere, and then naturally cooled to room temperature to obtain the renewable adsorption material for sewage treatment.

[0160] Examples 8-9

[0161] In Example 8, the renewable adsorption material for sewage treatment prepared in Example 6 and in Example 9, the renewable adsorption material for sewage treatment prepared in Example 7 were post-treated. The post-treatment process is as follows:

[0162] First, the regenerable adsorption material for sewage treatment prepared in Examples 6 and 7 above was placed in an argon atmosphere furnace, and then water vapor was loaded into the atmosphere furnace through argon as an activator, wherein the total flow rate of argon and water vapor was 60 mL / min, and the volume ratio of argon to water vapor was 1:1.5; and the furnace temperature in the atmosphere furnace was raised to 700°C at a rate of 8°C / min, kept warm for 1 hour, and naturally cooled to obtain the post-treated regenerable adsorption material for sewage treatment.

[0163] Examples 10-11

[0164] In Example 10, the renewable adsorption material for sewage treatment prepared in Example 6 and in Example 11, the renewable adsorption material for sewage treatment prepared in Example 7 were post-treated. The post-treatment process is as follows:

[0165] Hydrogen fluoride was used as the etching gas, and the renewable adsorption material for sewage treatment prepared in the above Examples 6 and 7 was plasma etched at an etching pressure of 50 Pa, a gas flow rate of 60 sccm, and a power of 60 W. During the plasma etching process, it should be ensured that the surface of the adsorption material was evenly exposed to the plasma. The etching time was 40 minutes. After the etching was completed, the adsorption material was washed with water and dried at a low temperature of 50°C to obtain the renewable adsorption material for sewage treatment after post-treatment.

[0166] Comparative Example 1

[0167] The only difference between it and the above-mentioned embodiment 1 is that no binder is added.

[0168] Comparative Example 2

[0169] The only difference between this embodiment and the above-mentioned embodiment 1 is that an equal weight of sludge is used instead of plastic particles to prepare the renewable adsorption material for sewage treatment. The preparation process is as follows:

[0170] The aggregate is directly mixed with the formulated amount of flux, pore former, binder and 40 parts by weight of water to obtain mixture I;

[0171] Then, the formulated amount of sludge particles is evenly mixed with mixture I to obtain mixture II;

[0172] The mixture II is placed into a mold and pressed into shape to obtain a profile III;

[0173] The profile III is placed in a high-temperature carbonization furnace, calcined and carbonized at 600° C. for 5 hours under the protection of an inert atmosphere, and then naturally cooled to room temperature to obtain the renewable adsorption material for sewage treatment.

[0174] Comparative Example 3

[0175] The only difference between this embodiment and the above-mentioned embodiment 1 is that no plastic particles are added.

[0176] Comparative Example 4

[0177] The only difference between this embodiment and the above-mentioned embodiment 4 is that no alkaline solution is used to perform alkaline soaking pretreatment on the industrial inorganic solid waste.

[0178] Test Example 1

[0179] The properties of the adsorption materials prepared in Examples 1 to 11 and Comparative Examples 1 to 4 were tested, and the structures are shown in Table 1 below:

[0180] Table 1 Performance test results of adsorption materials

[0181]

[0182] Test Example 2

[0183] The adsorption materials prepared in Examples 1 to 11 and Comparative Examples 1 to 4 were used to treat the same organic wastewater. The initial COD of the organic wastewater was 265 mg / L, and the amount of adsorption material added was 5 g / L. The results are shown in Table 2 below:

[0184] Table 2 Water treatment effect of adsorption materials

[0185]

[0186] Test Example 3

[0187] After the adsorbent prepared in Example 8 was saturated with adsorption, it was regenerated several times according to the adsorption material regeneration method of the present invention, and the COD removal rate (%) of the regenerated adsorbent was tested. The results are shown in FIG. Figure 3 .

[0188] The embodiments of the present application are described above in conjunction with the accompanying drawings. Unless there is a conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of this application, ordinary technicians in this field can also make many forms without departing from the purpose of this application and the scope of protection of the claims, all of which are within the protection of this application.

Claims

1. A method for preparing a renewable adsorption material for sewage treatment, characterized in that: The regenerable adsorption material for sewage treatment comprises the following raw materials in parts by weight: 70~120 parts of aggregate; 20~50 parts of flux; 10-20 parts of pore-forming agent; 3~10 parts of binder; 30~90 parts of plastic particles; and 3 to 15 parts by weight of reinforcing fibers, wherein the reinforcing fibers have a fire-resistant temperature of ≥1100° C.; The method for preparing the regenerable adsorption material for sewage treatment comprises the following steps: S1, prepare aggregate: (1) First, the natural inorganic mineral particles and industrial inorganic solid waste particles are screened to obtain natural inorganic mineral particles and industrial inorganic solid waste particles with an average particle size of 0.5-1 mm, natural inorganic mineral particles and industrial inorganic solid waste particles with an average particle size of 100-300 μm, and natural inorganic mineral particles and industrial inorganic solid waste particles with an average particle size of less than 100 μm; (2) Then, according to the weight ratio of large, medium and small inorganic particles in the aggregate, natural inorganic mineral particles or industrial inorganic solid waste particles of corresponding particle sizes are selected to prepare the aggregate, wherein the aggregate is a mixture of natural inorganic minerals and industrial inorganic solid waste, and the industrial inorganic solid waste accounts for 20-40wt% of the total aggregate; (3) The selected industrial inorganic solid waste particles are then dispersed in an alkaline solution, and after sufficient stirring, an alkaline suspension of the industrial inorganic solid waste particles is obtained. The alkaline suspension is heated to 50-90°C, kept warm and soaked for 1-3 hours, filtered, and dried to obtain pretreated industrial inorganic solid waste particles; (4) Mixing and stirring the pretreated industrial inorganic solid waste particles and natural inorganic mineral particles to obtain aggregate; S2, uniformly mixing the aggregate prepared in step S1 with the formulated amount of flux, pore former and binder to obtain mixture I; S3, uniformly mixing the formulated amount of plastic particles with mixture I to obtain mixture II; S4, shaping the mixture II to obtain a profile III; S5, placing the profile III in a high-temperature carbonization furnace for calcination and carbonization, and then naturally cooling to room temperature to obtain the carbonized profile IV, which is the renewable adsorption material for sewage treatment; In step S5, a staged carbonization process or a one-stage carbonization process is used to perform high-temperature carbonization treatment on the profile III: Among them, the segmented carbonization process is: (1) Pre-oxidation treatment: First, place the profile III in a high-temperature furnace at 300~500℃ under air atmosphere for pre-oxidation treatment. The pre-oxidation treatment time is 20~60min. (2) Carbonization treatment: placing the pre-oxidized profile III in a high-temperature carbonization furnace, calcining and carbonizing it at 600-1000°C for 2-4 hours under the protection of an inert atmosphere, and then naturally cooling it to room temperature to obtain the renewable adsorption material for sewage treatment; The one-stage carbonization process is as follows: placing the profile III in a high-temperature carbonization furnace, calcining and carbonizing it at 600-1000° C. for 3-5 hours under the protection of an inert atmosphere, and then naturally cooling it to room temperature to obtain the renewable adsorption material for sewage treatment.

2. The method for preparing a regenerable adsorbent material for sewage treatment according to claim 1, wherein: The binder is an inorganic sol, and the solid content of the inorganic sol is 5-20 wt %.

3. The method for preparing a regenerable adsorbent material for sewage treatment according to claim 1, wherein: The particle size of the plastic particles is 0.5-1 mm, and the plastic particles are selected from one or more of polyethylene, polypropylene, and polystyrene.

4. The method for preparing a regenerable adsorbent material for sewage treatment according to claim 1, wherein: After the adsorption material is obtained in step S5, the adsorption material obtained in step S5 is post-processed by a physical activation or plasma etching process, wherein: The physical activation process is as follows: first, the carbonized profile IV is placed in an argon atmosphere furnace, and then water vapor is loaded into the atmosphere furnace through argon gas as an activating agent, wherein the total flow rate of argon gas and water vapor is 50-80 mL / min, and the volume ratio of argon gas to water vapor is 1:(1.2-1.8); and the furnace temperature in the atmosphere furnace is raised to 500-800°C at a rate of 5-10°C / min, and then kept at this temperature for 0.5-1.5 hours. After natural cooling, the regenerable adsorption material for wastewater treatment after post-treatment is obtained; The plasma etching process is as follows: using hydrogen fluoride as the etching gas, the renewable adsorption material for sewage treatment is subjected to plasma etching at an etching pressure of 40-60 Pa, a gas flow rate of 40-80 sccm, and a power of 50-60 W. During the plasma etching process, it should be ensured that the surface of the adsorption material is evenly exposed to the plasma. The etching time is 20-60 minutes. After the etching is completed, the adsorption material is washed with water and dried at a low temperature of 40-80° C. to obtain the renewable adsorption material for sewage treatment after post-treatment.

5. The method for preparing a regenerable adsorbent material for sewage treatment according to claim 1, wherein: The regeneration process of the regenerable adsorbent material for sewage treatment comprises the following steps: P1, placing the adsorption saturated adsorption material in a high-temperature carbonization furnace, calcining and carbonizing at 600~1000℃ for 1~2h under argon atmosphere protection; P2, then water vapor is loaded into the atmosphere furnace as an activating agent through argon gas, wherein the total flow rate of argon gas and water vapor is 30~50mL / min, and the volume ratio of argon gas to water vapor is 1:(1.2~1.8); and the furnace temperature in the atmosphere furnace is raised to 500~800℃ at a rate of 10~15℃ / min, kept warm for 10~30min, and naturally cooled to obtain the regenerated adsorption material.

6. A renewable adsorption material for sewage treatment, characterized in that: The regenerable adsorption material for sewage treatment is an adsorption material prepared by the preparation method according to any one of claims 1 to 5.

Images