A kind of high waste PE material fired wire mesh shell carbon fixation aggregate and preparation method thereof

Abstract

The present application relates to the technical field of recycling agricultural waste PE materials, and in particular to a carbon-fixing aggregate made of wire mesh shells fired from high-waste PE materials and a preparation method thereof. The preparation method comprises the following steps: S1, pre-treating the collected PE materials; S2, carbon-fixing treatment of pumice to obtain carbon-fixing pumice; S3, preparing powdered adsorption pumice; S4, high-temperature calcination to form a wire mesh shell skeleton; S5, post-treatment. The present application provides a carbon-fixing aggregate made of wire mesh shells fired from high-waste PE materials and a preparation method thereof, which solves the problems of permeable concrete being susceptible to water erosion and poor aggregate carbon-fixing and sealing effects, and at the same time, comprehensively and effectively recycles waste agricultural mulch and drip irrigation tapes.

Description

Technical Field

[0001] The present application relates to the technical field of recycling agricultural waste PE materials, and in particular to a wire mesh shell carbon-fixing aggregate made by burning high-waste PE materials and a preparation method thereof. Background Art

[0002] In seasonal cold and drought areas, water resources are extremely precious. Permeable concrete is widely used in ecological slope protection, landscape greening, municipal sidewalks, ecological agricultural landscape roads and other engineering fields because it can effectively replenish groundwater by forming rainwater infiltration. At the same time, as one of the manufacturing materials of permeable concrete, the pore structure of pumice gives it a certain carbon fixation ability. It can prevent carbon dioxide emissions through carbon mineralization while improving its own aggregate performance; however, in the current application process, on the one hand, due to the long-term water erosion of permeable concrete, the damage it suffers during use is aggravated, and the service life is seriously insufficient. On the other hand, the pore structure of pumice permeable concrete aggregate is open pores. When absorbing CO2, some CO2 attachments float on the surface of the aggregate. During the secondary mixing and preparation process, due to the mutual friction between the aggregates, the CO2 attachments fall off, and there is carbon loss after carbon fixation, and the carbon fixation amount achieved is limited.

[0003] Inner Mongolia is a key area for the use of agricultural mulch films in my country, with large usage, wide coverage, and many mulch-covered crops. The promotion of water-saving irrigation year by year has greatly increased the use of agricultural drip irrigation tapes. Correspondingly, the recycling of waste agricultural mulch films and drip irrigation tapes is insufficient. According to incomplete statistics, the effective recycling rate of mulch films and drip irrigation tapes is less than 1 / 10, and a large amount of waste mulch films and drip irrigation tapes are randomly discarded and piled up.

[0004] At present, the recycling of waste mulch and drip irrigation tape usually includes recycling and remaking, and applying them to the manufacture of plastic products after processing. However, recycling and remaking requires relatively advanced technology and equipment to ensure that the recycled materials can meet the quality standards for reuse, which increases the cost of recycling and adds an additional burden. Therefore, the present application intends to provide a carbon-fixing aggregate, which effectively utilizes waste mulch and drip irrigation tape, which are PE wastes, while effectively improving the water erosion resistance of permeable concrete and the carbon fixation of aggregates. Summary of the invention

[0005] The present application provides a high-waste PE material fired wire mesh shell carbon-fixing aggregate and a preparation method thereof, which solves the problem that permeable concrete is susceptible to water erosion and the aggregate carbon-fixing and sealing effect is poor, and at the same time, comprehensively and effectively recycles waste agricultural mulch and drip irrigation tapes.

[0006] In a first aspect, a method for preparing a carbon-fixing aggregate of a wire mesh shell by burning high-waste PE materials is provided, which comprises the following steps:

[0007] S1. Pre-treat the collected PE materials:

[0008] S101, washing the PE material with water, then cleaning it with a detergent, and then drying the cleaned PE material to obtain a dry PE material, wherein the PE material comprises waste mulch film and a drip irrigation tape, and the mass ratio of the waste mulch film to the drip irrigation tape is 1.3:1;

[0009] S102, shredding the dried PE material so that the side length and diameter of the PE material are less than 2 mm to obtain crushed PE material;

[0010] S103, mixing the crushed PE material with 1.2 mol / L of dibutyric acid sebacic acid solution and 0.8 mol / L of epoxidized polyether solution, and sending the mixture into a hot melt extrusion granulator for granulation to obtain spherical PE high-waste particles, wherein the mass of the dibutyric acid sebacic acid solution is 1.1-1.2% of the mass of the crushed PE material, and the mass of the epoxidized polyether solution is 0.8-1% of the mass of the crushed PE material;

[0011] S104, crushing the spherical PE high-waste particles into PE high-waste powder with a particle size of 0.02-0.03 mm;

[0012] S2. Carry out carbon fixation treatment on the pumice to obtain carbon-fixed pumice: place the pumice in a carbon fixer, control the carbon dioxide concentration of the carbon fixer to 15%, the carbon fixation pressure to 1.01 KPa, and the rotation speed to 120 r / min, and maintain the carbon fixation time for 3 hours to obtain the carbon-fixed pumice;

[0013] S3, preparation of powdered adsorption pumice:

[0014] Spraying 0.7 to 0.9 parts of a 1% sodium silicate solution onto the surface of 97 to 114 parts of the carbon-fixing pumice to obtain a pretreated pumice;

[0015] 6.5-7.5 parts of the PE high-grade waste powder and 8.9-10.5 parts of the dispersant powder are uniformly mixed, and then mixed with 97.7-114.9 parts of the pretreated pumice and put into a self-weight mixer, and treated at a speed of 120 r / min for 3 minutes to obtain a powder adsorption pumice;

[0016] S4, high temperature calcination to form wire mesh skeleton wire mesh shell skeleton:

[0017] S401, preheating: placing the powder adsorption pumice at 120-130° C. for 3-4 minutes for preheating;

[0018] S402, melting: After 2 minutes, the pumice obtained in S401 is heated continuously at 150-170°C for 4-5 minutes to melt the powder on the surface;

[0019] S403, forming a wire mesh skeleton wire mesh shell skeleton: 2 minutes later, the pumice obtained in S402 is continuously heated at 190-220° C. for 7-9 minutes to form a wire mesh skeleton wire mesh shell skeleton on the surface of the pumice;

[0020] S404, cooling: placing the pumice with a wire mesh skeleton wire mesh shell skeleton obtained in S403 into an anaerobic environment for air cooling and maintaining the temperature for 20 minutes to obtain a high-waste PE material fired wire mesh shell carbon-fixing aggregate;

[0021] S5. Post-processing: The high-waste PE material fired wire mesh shell carbon-fixing aggregate prepared in S404 is placed in a standard state for curing for 28 days, wherein the standard state is temperature: 20±2°C, humidity: above 95%.

[0022] Preferably, in S101, the cleaning agent is selected from Tween 80 or Triton X-100.

[0023] Preferably, in S103, the barrel temperature of the hot melt extrusion granulator is 160-180°C, the feeding speed and the screw speed are 80-100rpm, and the mesh plate size is 4mm.

[0024] Preferably, in S3, the particle size of the dispersant powder is 0.02-0.03 mm.

[0025] Preferably, in S3, the dispersant powder comprises kaolin powder and talcum powder, and the mass ratio of the kaolin powder to the talcum powder is 1:1.

[0026] Preferably, it also includes:

[0027] The steps S1, S3 and S4 were repeated three times in total.

[0028] In a second aspect, a high-waste PE material fired wire mesh shell carbon-fixing aggregate is provided, which is prepared by any of the above-described methods for preparing a high-waste PE material fired wire mesh shell carbon-fixing aggregate.

[0029] The beneficial effects of the technical solution provided by this application include:

[0030] The present application provides a high-waste PE material sintered wire mesh shell carbon-fixing aggregate and a preparation method thereof, which has the following advantages:

[0031] (1) The prepared PE high-waste powder is fired to obtain a wire mesh shell to achieve effective secondary treatment of pumice aggregate after carbon fixation, which can reduce carbon loss after carbon fixation, achieve the purpose of locking carbon fixation efficiency, strengthening and stabilizing carbon fixation effect, and help improve the mechanical properties of aggregate;

[0032] (2) Due to the large surface open porosity and specific surface area of ​​pumice, it serves as an embedded matrix, which enhances the contact area with the wire mesh shell obtained by firing PE high-waste powder, improves the mechanical bite force between the two, and can make them firmly bonded, not easy to fall off, and effectively fix carbon;

[0033] (3) The surface of the wire mesh shell obtained by firing the prepared PE high-waste powder is hydrophobic. It is embedded in the aggregate and can effectively reduce the internal dynamic erosion caused by water erosion of the aggregate, improve the performance of the aggregate, and optimize the anti-water erosion performance and durability of the concrete;

[0034] (4) PE high-waste powder (plastic) has fluidity in the molten state, and the dispersant has the characteristic of a high melting point. The combination of the two can reflect the "melting bridge" effect in the hot melting process. Through multiple coatings + high-temperature hot melting, the PE high-waste powder (plastic) can be "melted" and the dispersant can be "dissolved but not melted" in stages, thereby forming a spatial mesh structure, effectively increasing its contact area with the aggregate surface, and then increasing the bonding force between the slurry and the aggregate during the coagulation and hardening process of the permeable concrete, thereby improving the aggregate performance;

[0035] (5) The preparation method provided in the present application can control the thickness of the wire mesh shell and the number of layers of the wire mesh shell by controlling the number of times of preparing the powder adsorption pumice and high-temperature calcination, thereby preparing a multi-layer flexible shell, and adsorbing it on the aggregate, which can make the aggregate flexible and effectively improve the ductility, crack resistance, impact resistance and freeze-thaw resistance of the aggregate;

[0036] (6) The preparation method provided in the present application can control the porosity of the wire mesh shell by controlling the particle size of the powder. When calcined at high temperature, the powder is in a fluid state, and a fluid membrane is formed on the pretreated pumice stone, thereby more accurately controlling the separation ability of the membrane and increasing the selectivity of the membrane for specific substances, thereby improving the accuracy of the separation process and the filtration efficiency for specific molecules or particles, controlling the fluid flux of the membrane, and optimizing the passage speed and flow characteristics of the fluid;

[0037] (7) The preparation method provided in the present application recycles and granulates waste mulch film and drip irrigation tape into powder, which is then adsorbed onto a pumice porous medium that has been treated with carbon fixation to lock in the carbon fixation effect. After multiple adsorption treatments, high-waste PE materials can be effectively absorbed. This special process not only improves the performance of the aggregate, but also helps protect the environment, save resources and reduce costs, promote economic development and create employment opportunities. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0039] Figure 1 A flow chart of the method for preparing carbon-fixing aggregate of wire mesh shell by burning high-waste PE materials provided in this application;

[0040] Figure 2 Schematic diagram of the preparation method of wire mesh shell carbon-fixing aggregate by sintering high-waste PE materials provided in this application. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings 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 without making creative work are within the scope of protection of this application.

[0042] See also Figure 1 and Figure 2 As shown, the present application provides a method for preparing carbon-fixing aggregate (hereinafter referred to as carbon-fixing aggregate) by burning wire mesh shells with high-waste PE materials, which can solve the problems in the related art that permeable concrete is easily eroded by water and the carbon-fixing efficiency of pumice aggregate is not high, and at the same time, it also comprehensively and effectively recycles waste agricultural mulch and drip irrigation tape. The preparation method includes the following steps:

[0043] S1. Pre-treat the collected PE materials:

[0044] S101, washing the PE material with water, then washing it with a detergent, and then drying the washed PE material to obtain a dry PE material, wherein the PE material comprises waste mulch and drip irrigation tape, and the mass ratio of the waste mulch to the drip irrigation tape is 1.3: 1. Specifically, this step is used to remove soil, plant residues and impurities attached to the surface of the waste mulch and the drip irrigation tape.

[0045] In some embodiments, the cleaning agent is selected from one of Tween 80 and Triton X-100. Both Tween 80 and Triton X-100 are non-ionic surfactants that can remove dust and fine particles attached to the surface of objects, and make the particles easier to wash away by wetting the surface of the particles and reducing the adhesion between the particles and the surface.

[0046] S102, shredding the dried PE material so that the side length and diameter of the PE material are less than 2 mm to obtain crushed PE material for subsequent operations;

[0047] S103, mixing the crushed PE material with 1.2 mol / L of dibutyric acid sebacic acid solution and 0.8 mol / L of epoxidized polyether solution, and sending the mixture into a hot melt extrusion granulator for granulation to obtain spherical PE high-waste particles, wherein the mass of the dibutyric acid sebacic acid solution is 1.1-1.2% of the mass of the crushed PE material, and the mass of the epoxidized polyether solution is 0.8-1% of the mass of the crushed PE material, so as to increase the repulsive force between the crushed PE materials and prevent the particles from approaching and agglomerating each other;

[0048] Specifically, the barrel temperature of the hot melt extrusion granulator is 160-180°C, the feeding speed and the screw speed are 80-100rpm, the mesh plate size is 4mm, and after the processing is completed, spherical PE high waste particles are obtained.

[0049] S104, crushing the spherical PE high-waste particles into PE high-waste powder with a particle size of 0.02-0.03 mm, and a plastic grinding machine can be used to grind the spherical PE high-waste particles;

[0050] S2. Carry out carbon fixation treatment on the pumice to obtain carbon-fixed pumice: place the pumice in a carbon fixer, control the carbon dioxide concentration of the carbon fixer to 15%, the carbon fixation pressure to 1.01 KPa, and the rotation speed to 120 r / min, and maintain the carbon fixation time for 3 hours to obtain the carbon-fixed pumice;

[0051] S3, preparation of powdered adsorption pumice:

[0052] Spraying 0.7 to 0.9 parts of a 1% sodium silicate solution on the surface of 97 to 114 parts of the carbon-fixing pumice to obtain the pretreated pumice so that the pumice is in a wet state;

[0053] 6.5-7.5 parts of the PE high-grade waste powder and 8.9-10.5 parts of the dispersant powder are uniformly mixed, and then mixed with 97.7-114.9 parts of pre-treated pumice and put into a self-weight mixer, and treated at a speed of 120 r / min for 3 minutes to obtain a powder adsorption pumice, wherein the pre-treated pumice with a wet surface is conducive to the adsorption of the PE high-grade waste powder and the dispersant powder;

[0054] In some embodiments, the particle size of the dispersant powder is 0.02-0.03 mm, and the porosity of the membrane is controlled by controlling the powder particle size.

[0055] In some embodiments, the dispersant powder includes kaolin powder and talcum powder, and the mass ratio of the kaolin powder to the talcum powder is 1: 1. The dispersant is used to disperse the PE high waste powder to prevent adhesion, avoid agglomeration due to static electricity or moisture, and improve the performance of PE products to a certain extent.

[0056] S4, high temperature calcination to form a wire mesh shell skeleton:

[0057] S401, preheating: placing the powder adsorption pumice at 120-130° C. for 3-4 minutes for preheating;

[0058] S402, melting: After 2 minutes, the pumice obtained in S401 is heated continuously at 150-170°C for 4-5 minutes to melt the powder on the surface;

[0059] S403, forming a wire mesh shell skeleton: 2 minutes later, the pumice obtained in S402 is continuously heated at 190-220° C. for 7-9 minutes to form a wire mesh shell skeleton on the surface of the pumice;

[0060] S404, cooling: placing the pumice with the wire mesh shell skeleton obtained in S403 into an anaerobic environment for air cooling and maintaining the temperature for 20 minutes to obtain a wire mesh shell carbon-fixing aggregate made by burning high-waste PE materials.

[0061] After multi-stage temperature-controlled calcination, the PE high-waste powder is made to present a molten state, and under the flexible aggregation effect of the micropowder, a single-layer "wire mesh structure" membrane skeleton is formed.

[0062] Furthermore, PE material itself is hydrophobic. The wire mesh shell carbon-fixing aggregate obtained by firing high-waste powder-based PE material can form a unidirectional membrane flexible wrapping for the carbon-fixing aggregate, and form secondary carbon sequestration for the carbon-fixing pumice aggregate, thereby achieving effective carbon fixation and chemical quality improvement and efficiency enhancement of the aggregate; on this basis, due to the protective effect of its surface hydrophobic polymer wire mesh flexible shell, on the one hand, it greatly improves the contact area with the surface of the pumice aggregate, and increases the bonding force between the slurry and the aggregate during the coagulation and hardening process of the permeable concrete; on the other hand, it greatly reduces the internal dynamic erosion of the aggregate after being exposed to water, and better optimizes the aggregate's anti-water erosion performance, thereby improving the anti-water erosion durability of the permeable concrete.

[0063] Agricultural waste PE materials such as waste mulch and drip irrigation tapes are adsorbed on carbon-fixing pumice, which not only locks in the carbon sequestration effect of the pumice aggregate, but also improves the mechanical, physical and chemical properties of the aggregate, especially in terms of improving the resistance to water erosion in seasonal freeze-thaw areas, providing a green, environmentally friendly and highly durable aggregate system for the preparation and application of regional permeable concrete components.

[0064] In some embodiments, when preparing high-waste PE material fired wire mesh shell carbon fixation aggregate, steps S1, S3 and S4 are repeated three times in total, and a multi-layer spatial wire mesh flexible membrane is formed through multiple adsorption and multi-stage temperature controlled calcination.

[0065] Of course, in order to form a denser wire mesh structure on the aggregate surface, step S4 may be repeated multiple times to form wire mesh structures with different pores.

[0066] S5. Post-treatment: The high-waste PE material fired wire mesh shell carbon-fixing aggregate prepared in S404 is placed in a standard environment with a temperature of 20±2°C and a humidity of more than 95% for curing for 28 days.

[0067] The present application provides the following examples, and it should be noted that the "parts" described in the examples are parts by mass:

[0068] Example 1

[0069] The method for preparing carbon-fixing aggregate of wire mesh shell by burning high-waste PE materials provided in this embodiment comprises the following steps:

[0070] S1. Pre-treat the collected PE materials:

[0071] S101, 3.9 parts of the collected waste mulch and 3 parts of the drip irrigation tapes were washed with water in a circulating manner, then washed with 1% Tween 80 for 25 minutes, and then dried to obtain a dry PE material;

[0072] S102, shredding the dried PE material so that the side length and diameter of the PE material are less than 2 mm to obtain crushed PE material;

[0073] S103, 6.9 parts of the crushed PE material, 0.08 parts of a 1.2 mol / L dibutyric acid solution of sebacic acid and 0.06 parts of a 0.8 mol / L epoxidized polyether solution are mixed evenly, and the mixture is fed into a hot melt extrusion granulator, the granulator is started, the barrel temperature is controlled to be 170° C., the feeding speed and the screw speed are controlled to be 90 rpm, and the mesh plate size is controlled to be 4 mm. After the treatment, spherical PE high waste particles are obtained;

[0074] S104, using a plastic grinder to grind the spherical PE high-waste particles into plastic powder with a particle size of 0.02-0.03 mm, to obtain 6.95 parts of PE high-waste powder.

[0075] It should be noted that the particle size of the PE high waste powder is set to 0.02~0.03mm here. This is because the particle size of the powder ground out by the plastic grinder is mostly within this range, and the PE high waste powder within this particle size range can achieve better results in subsequent treatment. In order to efficiently and fully utilize the PE high waste powder, the particle size of the PE high waste powder here is set to a range value.

[0076] S2. Carry out carbon fixation treatment on the pumice to obtain carbon-fixed pumice: 97 parts of pumice are placed in a carbon fixer, and the carbon dioxide concentration, carbon fixation pressure and rotation speed of the carbon fixer are controlled to be 15%, 1.01 KPa and 120 r / min, and the carbon fixation time is maintained for 3 hours to obtain the carbon-fixed pumice;

[0077] S3, preparation of powdered adsorption pumice:

[0078] Spraying 0.7 parts of a 1% sodium silicate solution on the surface of 97 parts of the carbon-fixing pumice to obtain a pretreated pumice so that the pumice is in a wet state;

[0079] 6.95 parts of the PE high-grade waste powder and 8.9 parts of the dispersant powder are uniformly mixed, and then mixed with 97.7 parts of pre-treated pumice and put into a self-weight mixer, and treated at a speed of 120 r / min for 3 minutes to obtain a powder adsorption pumice. The pre-treated pumice with a wet surface is conducive to the adsorption of the PE high-grade waste powder and the dispersant powder;

[0080] The dispersant includes 4.45 parts of kaolin powder and 4.45 parts of talc powder.

[0081] S4, high temperature calcination to form a wire mesh shell skeleton:

[0082] S401, preheating: placing the powder adsorption pumice at 130° C. for 3 minutes for preheating;

[0083] S402, melting: After 2 minutes, the pumice obtained in S401 is heated at 160°C for 4 minutes to melt the powder on the surface;

[0084] S403, forming a wire mesh shell skeleton: 2 minutes later, the pumice obtained in S402 is continuously heated at 200° C. for 8 minutes to form a wire mesh shell skeleton on the surface of the pumice;

[0085] S404, cooling: placing the pumice with the wire mesh shell skeleton obtained in S403 into an anaerobic environment for air cooling and maintaining the temperature for 20 minutes to obtain a wire mesh shell carbon-fixing aggregate made by burning high-waste PE materials.

[0086] S5. Post-processing: The high-waste PE material fired wire mesh shell carbon-fixing aggregate prepared in S404 is placed in a standard state (temperature: 20±2°C, humidity: above 95%) for curing for 28 days.

[0087] Example 2

[0088] The method for preparing carbon-fixing aggregate of wire mesh shell by burning high-waste PE materials provided in this embodiment comprises the following steps:

[0089] S1. Pre-treat the collected PE materials:

[0090] S101, 3.64 parts of the collected waste mulch and 2.8 parts of the drip irrigation tapes were washed with water in a circulating manner, then washed with 1% Tween 80 for 25 minutes, and then dried to obtain a dry PE material;

[0091] S102, shredding the dried PE material so that the side length and diameter of the PE material are less than 2 mm to obtain crushed PE material;

[0092] S103, 6.44 parts of the crushed PE material, 0.075 parts of a 1.2 mol / L dibutyric acid solution of sebacic acid and 0.06 parts of a 0.8 mol / L epoxidized polyether solution were mixed evenly, and sent to a hot melt extrusion granulator, the granulator was started, the barrel temperature was controlled to be 170°C, the feeding speed and the screw speed were controlled to be 90 rpm, and the mesh plate size was controlled to be 4 mm. After the treatment, spherical PE high waste particles were obtained;

[0093] S104, using a plastic grinder to grind the spherical PE high-waste particles into plastic powder with a particle size of 0.02-0.03 mm, to obtain 6.5 parts of PE high-waste powder.

[0094] It should be noted that the particle size of the PE high waste powder is set to 0.02~0.03mm here. This is because the particle size of the powder ground out by the plastic grinder is mostly within this range, and the PE high waste powder within this particle size range can achieve better results in subsequent treatment. In order to efficiently and fully utilize the PE high waste powder, the particle size of the PE high waste powder here is set to a range value.

[0095] S2. Carry out carbon fixation treatment on the pumice to obtain carbon-fixed pumice: place 105 parts of pumice in a carbon fixer, control the carbon dioxide concentration of the carbon fixer to 15%, the carbon fixation pressure to 1.01 KPa, and the rotation speed to 120 r / min, and maintain the carbon fixation time for 3 hours to obtain the carbon-fixed pumice;

[0096] S3, preparation of powdered adsorption pumice:

[0097] Spraying 0.8 parts of a 1% sodium silicate solution on the surface of 105 parts of the carbon-fixing pumice to obtain a pretreated pumice so that the pumice is in a wet state;

[0098] 6.5 parts of the PE high-grade waste powder and 9.6 parts of the dispersant powder are evenly mixed, and then mixed with 105.8 parts of pretreated pumice and put into a self-weight mixer, and treated at a speed of 120 r / min for 3 minutes to obtain a powder adsorption pumice. The pretreated pumice with a wet surface is conducive to the adsorption of the PE high-grade waste powder and the dispersant powder;

[0099] The dispersant includes 4.8 parts of kaolin powder and 4.8 parts of talc powder.

[0100] S4, high temperature calcination to form a wire mesh shell skeleton:

[0101] S401, preheating: placing the powder adsorption pumice at 120° C. for 4 minutes for preheating;

[0102] S402, melting: After 2 minutes, the pumice obtained in S401 is heated at 170°C for 5 minutes to melt the powder on the surface;

[0103] S403, forming a wire mesh shell skeleton: 2 minutes later, the pumice obtained in S402 is continuously heated at 220° C. for 7 minutes to form a wire mesh shell skeleton on the surface of the pumice;

[0104] S404, cooling: placing the pumice with the wire mesh shell skeleton obtained in S403 into an anaerobic environment for air cooling and maintaining the temperature for 20 minutes to obtain a wire mesh shell carbon-fixing aggregate made by burning high-waste PE materials.

[0105] S5. Post-processing: The high-waste PE material fired wire mesh shell carbon-fixing aggregate prepared in S404 is placed in a standard state (temperature: 20±2°C, humidity: above 95%) for curing for 28 days.

[0106] Example 3

[0107] The method for preparing carbon-fixing aggregate of wire mesh shell by burning high-waste PE materials provided in this embodiment comprises the following steps:

[0108] S1. Pre-treat the collected PE materials:

[0109] S101, 4.16 parts of the collected waste mulch and 3.2 parts of the drip irrigation tape were washed with water in a circulating manner, then washed with 1% Triton X-100 for 25 minutes, and then dried to obtain a dry PE material;

[0110] S102, shredding the dried PE material so that the side length and diameter of the PE material are less than 2 mm to obtain crushed PE material;

[0111] S103, 7.36 parts of the crushed PE material, 0.085 parts of a 1.2 mol / L dibutyric acid solution of sebacic acid and 0.07 parts of a 0.8 mol / L epoxidized polyether solution were mixed evenly, and fed into a hot melt extrusion granulator, the granulator was started, the barrel temperature was controlled to be 170°C, the feeding speed and the screw speed were controlled to be 90 rpm, and the mesh plate size was controlled to be 4 mm. After the treatment, spherical PE high waste particles were obtained;

[0112] S104, using a plastic grinder to grind the spherical PE high-waste particles into plastic powder with a particle size of 0.02-0.03 mm, to obtain 7.5 parts of PE high-waste powder.

[0113] It should be noted that the particle size of the PE high waste powder is set to 0.02~0.03mm here. This is because the particle size of the powder ground out by the plastic grinder is mostly within this range, and the PE high waste powder within this particle size range can achieve better results in subsequent treatment. In order to efficiently and fully utilize the PE high waste powder, the particle size of the PE high waste powder here is set to a range value.

[0114] S2. Carry out carbon fixation treatment on the pumice to obtain carbon-fixed pumice: 114 parts of pumice are placed in a carbon fixer, and the carbon dioxide concentration, carbon fixation pressure and rotation speed of the carbon fixer are controlled to be 15%, 1.01 KPa and 120 r / min, and the carbon fixation time is maintained for 3 hours to obtain the carbon-fixed pumice;

[0115] S3, preparation of powdered adsorption pumice:

[0116] Spraying 0.9 parts of a 1% sodium silicate solution on the surface of 114 parts of the carbon-fixing pumice to obtain a pretreated pumice so that the pumice is in a wet state;

[0117] 7.5 parts of the PE high-grade waste powder and 10.5 parts of the dispersant powder are uniformly mixed, and then mixed with 114.9 parts of pretreated pumice and put into a self-weight mixer, and treated at a speed of 120 r / min for 3 minutes to obtain a powder adsorption pumice. The pretreated pumice with a wet surface is conducive to the adsorption of the PE high-grade waste powder and the dispersant powder;

[0118] The dispersant includes 5.25 parts of kaolin powder and 5.25 parts of talc powder.

[0119] S4, high temperature calcination to form a wire mesh shell skeleton:

[0120] S401, preheating: placing the powder adsorption pumice at 125° C. for 3 minutes for preheating;

[0121] S402, melting: After 2 minutes, the pumice obtained in S401 is heated at 150°C for 4 minutes to melt the powder on the surface;

[0122] S403, forming a wire mesh shell skeleton: 2 minutes later, the pumice obtained in S402 is continuously heated at 190° C. for 9 minutes to form a wire mesh shell skeleton on the surface of the pumice;

[0123] S404, cooling: placing the pumice with the wire mesh shell skeleton obtained in S403 into an anaerobic environment for air cooling and maintaining the temperature for 20 minutes to obtain a wire mesh shell carbon-fixing aggregate made by burning high-waste PE materials.

[0124] S5. Post-processing: The high-waste PE material fired wire mesh shell carbon-fixing aggregate prepared in S404 is placed in a standard state (temperature: 20±2°C, humidity: above 95%) for curing for 28 days.

[0125] Example 4

[0126] The method for preparing carbon-fixing aggregate of wire mesh shell by burning high-waste PE materials provided in this embodiment comprises the following steps:

[0127] S1. Pre-treat the collected PE materials:

[0128] S101, 3.9 parts of the collected waste mulch and 3 parts of the drip irrigation tapes were washed with water in a circulating manner, then washed with 1% Tween 80 for 25 minutes, and then dried to obtain a dry PE material;

[0129] S102, shredding the dried PE material so that the side length and diameter of the PE material are less than 2 mm to obtain crushed PE material;

[0130] S103, 6.9 parts of the crushed PE material, 0.08 parts of a 1.2 mol / L dibutyric acid solution of sebacic acid and 0.06 parts of a 0.8 mol / L epoxidized polyether solution are mixed evenly, and the mixture is fed into a hot melt extrusion granulator, the granulator is started, the barrel temperature is controlled to be 170° C., the feeding speed and the screw speed are controlled to be 90 rpm, and the mesh plate size is controlled to be 4 mm. After the treatment, spherical PE high waste particles are obtained;

[0131] S104, using a plastic grinder to grind the spherical PE high-waste particles into plastic powder with a particle size of 0.02-0.03 mm, to obtain 6.95 parts of PE high-waste powder.

[0132] It should be noted that the particle size of the PE high waste powder is set to 0.02~0.03mm here. This is because the particle size of the powder ground out by the plastic grinder is mostly within this range, and the PE high waste powder within this particle size range can achieve better results in subsequent treatment. In order to efficiently and fully utilize the PE high waste powder, the particle size of the PE high waste powder here is set to a range value.

[0133] S2. Carry out carbon fixation treatment on the pumice to obtain carbon-fixed pumice: 97 parts of pumice are placed in a carbon fixer, and the carbon dioxide concentration, carbon fixation pressure and rotation speed of the carbon fixer are controlled to be 15%, 1.01 KPa and 120 r / min, and the carbon fixation time is maintained for 3 hours to obtain the carbon-fixed pumice;

[0134] S3, preparation of powdered adsorption pumice:

[0135] Spraying 0.7 parts of a 1% sodium silicate solution on the surface of 97 parts of the carbon-fixing pumice to obtain a pretreated pumice so that the pumice is in a wet state;

[0136] 6.95 parts of the PE high-grade waste powder and 8.9 parts of the dispersant powder are uniformly mixed, and then mixed with 97.7 parts of pre-treated pumice and put into a self-weight mixer, and treated at a speed of 120 r / min for 3 minutes to obtain a powder adsorption pumice. The pre-treated pumice with a wet surface is conducive to the adsorption of the PE high-grade waste powder and the dispersant powder;

[0137] The dispersant includes 4.45 parts of kaolin powder and 4.45 parts of talc powder.

[0138] S4, high temperature calcination to form a wire mesh shell skeleton:

[0139] S401, preheating: placing the powder adsorption pumice at 130° C. for 3 minutes for preheating;

[0140] S402, melting: After 2 minutes, the pumice obtained in S401 is heated at 160°C for 4 minutes to melt the powder on the surface;

[0141] S403, forming a wire mesh shell skeleton: 2 minutes later, the pumice obtained in S402 is continuously heated at 200° C. for 8 minutes to form a wire mesh shell skeleton on the surface of the pumice;

[0142] S404, cooling: placing the pumice with the wire mesh shell skeleton obtained in S403 into an anaerobic environment for air cooling and maintaining the temperature for 20 minutes to obtain a wire mesh shell carbon-fixing aggregate made by burning high-waste PE materials.

[0143] Steps S1, S3 and S4 are repeated twice. That is, in this embodiment, powder adsorption and high-temperature calcination are performed three times on the pretreated pumice, and three layers of wire mesh shell skeletons are embedded on the carbon-fixing pumice.

[0144] It should be noted that in the second operation of step S3, the carbon-fixing pumice is the pumice coated with a layer of wire mesh shell skeleton after the first operation of step S404, the concentration and spraying amount of the sodium silicate solution sprayed on its surface remain unchanged, and the amount of PE high waste powder and dispersant powder used remains unchanged. The operation of the third step S3 is similar, the carbon-fixing pumice is the pumice coated with two layers of wire mesh shell skeleton after the second operation of step S404, the concentration and spraying amount of the sodium silicate solution sprayed on its surface remain unchanged, and the amount of PE high waste powder and dispersant powder used remains unchanged.

[0145] S5. Post-processing: The multi-layer wire mesh shell carbon-fixing aggregate prepared by sintering the high-waste PE material obtained in S404 is placed in a standard state (temperature: 20±2°C, humidity: above 95%) for curing for 28 days.

[0146] Comparative Example 1

[0147] The method for preparing the carbon-fixing aggregate provided in this comparative example only performs steps S2 and S4 in Example 1.

[0148] Comparative Example 2

[0149] The method for preparing carbon-fixing aggregate provided in this comparative example is the same as that in Example 1, except that in S4, S401 to S403 are not performed, and the powder adsorption pumice is only placed at 163° C. for 15 minutes, and then the cooling in S404 is performed. The remaining steps are the same as those in Example 1.

[0150] Specifically, the raw materials for preparing the carbon-fixing aggregates provided in Examples 1 to 4 and Comparative Examples 1 to 2 are shown in Table 1.

[0151] Table 1

[0152]

[0153] Furthermore, the performance of the carbon-fixing aggregates prepared in Examples 1 to 4 and Comparative Examples 1 to 2 was tested, and the test results are shown in Table 2.

[0154] Table 2

[0155]

[0156] It can be known that Examples 1 to 4 used high-waste PE materials for firing, and formed a wire mesh shell on the pumice aggregate. Compared with Comparative Example 1, it has a higher apparent density, a lower water absorption rate and a higher cylinder pressure strength. Example 4 has undergone three repetitions of step S4 to form a three-layer wire mesh shell on the outer surface of the pumice aggregate. Its apparent density and cylinder pressure strength are higher than those of Examples 1 to 3, and its water absorption rate is lower than that of Examples 1 to 3. It can be expected that if steps S1, S3 and S4 are repeated multiple times, a multi-layer wire mesh shell carbon-fixing aggregate can be obtained, and the water absorption rate will be further reduced.

[0157] The preparation method of the carbon-fixing aggregate made of wire mesh shell by firing high-waste PE materials provided in the present application realizes the recycling, cleaning and utilization of PE wastes such as waste mulch and drip irrigation tapes, and is adsorbed on the carbon-fixing pumice aggregate in a wet state (it should be noted that it is not limited to pumice, but can also be a rock with a porous structure similar to pumice), and is treated by high-temperature anaerobic heating to form a new aggregate system; during the adsorption process, the high-waste PE material and the dispersant are uniformly and flexibly embedded in the pumice under the synergistic effect, and the high-waste PE material is caused to present a fusible state through multi-stage temperature-controlled calcination, and under the flexible aggregation effect of the micropowder, a multi-layer spatial wire mesh flexible membrane is formed through multiple adsorptions and multi-stage temperature-controlled calcination.

[0158] Agricultural waste PE materials such as waste mulch and drip irrigation tapes are adsorbed on carbon-fixing pumice. While locking in the carbon sequestration effect of the pumice aggregate, the mechanical, physical and chemical properties of the aggregate are improved, especially the improvement of the resistance to water erosion in seasonal freeze-thaw areas, providing a green, environmentally friendly and highly durable aggregate system for the preparation and application of regional permeable concrete components.

[0159] The present application also provides a carbon-fixing aggregate made of wire mesh shells fired from high-waste PE materials, which is prepared by any of the preparation methods of the carbon-fixing aggregate made of wire mesh shells fired from high-waste PE materials provided in Examples 1 to 4 above.

[0160] Further, see Figure 2 As shown, the high-waste PE material fired wire mesh shell carbon-fixing aggregate prepared by the method of the present application can be used in scenes such as ecological slope protection, landscaping, municipal sidewalks and ecological agricultural landscape roads after preparing permeable concrete. Its good permeability and hydrophobicity can be suitable for permeable scenes, while promoting rapid infiltration of rainwater and reducing surface runoff, it also extends its service life.

[0161] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A method for preparing carbon-fixing aggregate by burning wire mesh shells with high-waste PE materials, characterized in that: It includes the following steps: S1. Pre-treat the collected PE materials: S101, washing the PE material with water, then cleaning it with a detergent, and then drying the cleaned PE material to obtain a dry PE material, wherein the PE material comprises waste mulch film and a drip irrigation tape, and the mass ratio of the waste mulch film to the drip irrigation tape is 1.3:1; S102, shredding the dried PE material so that the side length and diameter of the PE material are less than 2 mm to obtain crushed PE material; S103, mixing the crushed PE material with 1.2 mol / L of dibutyric acid sebacic acid solution and 0.8 mol / L of epoxidized polyether solution, and sending the mixture into a hot melt extrusion granulator for granulation to obtain spherical PE high-waste particles, wherein the mass of the dibutyric acid sebacic acid solution is 1.1-1.2% of the mass of the crushed PE material, and the mass of the epoxidized polyether solution is 0.8-1% of the mass of the crushed PE material; S104, crushing the spherical PE high-waste particles into PE high-waste powder with a particle size of 0.02-0.03 mm; S2. Carry out carbon fixation treatment on the pumice to obtain carbon-fixed pumice: place the pumice in a carbon fixer, control the carbon dioxide concentration of the carbon fixer to 15%, the carbon fixation pressure to 1.01 KPa, and the rotation speed to 120 r / min, and maintain the carbon fixation time for 3 hours to obtain the carbon-fixed pumice; S3, preparation of powdered adsorption pumice: Spraying 0.7 to 0.9 parts by mass of a 1% sodium silicate solution on the surface of 97 to 114 parts of the carbon-fixing pumice to obtain a pretreated pumice; 6.5-7.5 parts of the PE high waste powder and 8.9-10.5 parts of the dispersant powder were mixed evenly by weight, and then mixed with 97.7-114.9 parts of pre-treated pumice and put into a self-weight mixer, and treated at a speed of 120 r / min for 3 minutes to obtain powder adsorption pumice; S4, high temperature calcination to form a wire mesh shell skeleton: S401, preheating: placing the powder adsorption pumice at 120-130° C. for 3-4 minutes for preheating; S402, melting: After 2 minutes, the pumice obtained in S401 is heated continuously at 150-170°C for 4-5 minutes to melt the powder on the surface; S403, forming a wire mesh shell skeleton: 2 minutes later, the pumice obtained in S402 is continuously heated at 190-220° C. for 7-9 minutes to form a wire mesh shell skeleton on the surface of the pumice; S404, cooling: placing the pumice with a wire mesh shell skeleton obtained in S403 in an anaerobic environment for air cooling and maintaining the temperature for 20 minutes to obtain a wire mesh shell carbon-fixing aggregate made by burning high-waste PE materials; S5. Post-processing: The high-waste PE material fired wire mesh shell carbon-fixing aggregate prepared in S404 is placed in a standard state for curing for 28 days, wherein the standard state is temperature: 20±2°C, humidity: above 95%.

2. The method for preparing carbon-fixing aggregate by burning wire mesh shells with high-waste PE materials as claimed in claim 1, characterized in that: In S101, the cleaning agent is selected from Tween 80 or Triton X-100.

3. The method for preparing carbon-fixing aggregate by burning wire mesh shells with high-waste PE materials as claimed in claim 1, characterized in that: In the S103, the barrel temperature of the hot melt extrusion granulator is 160-180°C, the feeding speed and the screw speed are 80-100 rpm, and the mesh plate size is 4 mm.

4. The method for preparing carbon-fixing aggregate by burning wire mesh shells with high-waste PE materials as claimed in claim 1, characterized in that: In S3, the particle size of the dispersant powder is 0.02-0.03 mm.

5. The method for preparing carbon-fixing aggregate by burning wire mesh shells from high-waste PE materials as claimed in claim 1 or 4, characterized in that: In S3, the dispersant powder includes kaolin powder and talcum powder, and the mass ratio of the kaolin powder to the talcum powder is 1:

1.

6. The method for preparing carbon-fixing aggregate by burning wire mesh shells from high-waste PE materials as claimed in claim 1, characterized in that: It also includes: The steps S1, S3 and S4 were repeated three times in total.

7. A carbon-fixing aggregate made of wire mesh shells fired from high-waste PE materials, which is prepared by the preparation method of the carbon-fixing aggregate made of wire mesh shells fired from high-waste PE materials according to any one of claims 1 to 6.

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