Concrete with wastewater purification function as well as preparation method and application thereof

Abstract

The invention discloses concrete with a wastewater purification function and a preparation method and application thereof.The concrete with the wastewater purification function is prepared from adsorption particles, a solid waste-based material and an alkaline activator, and the adsorption particles are prepared from a biomass mixed material and sludge; the solid waste-based material comprises construction waste, titanium gypsum and asbestos tailings, the biomass mixed material and sludge are prepared into adsorption particles, the adsorption performance of the adsorption particles is utilized to improve the strength and durability of the concrete with the wastewater purification function, and the solid waste-based material such as the construction waste, the titanium gypsum and the asbestos tailings effectively utilizes waste resources, so that the environment is protected. The alkali activator can accelerate chemical reaction in the activation material and improve the strength of the concrete with the wastewater purification function, and by effectively utilizing the solid waste material and the biomass mixture, not only is the resource saved, but also the pollution to the environment is reduced. By using the alkaline activator, the early strength of the concrete with the wastewater purification function is improved, and meanwhile, the durability is enhanced.

Description

Technical Field

[0001] The invention relates to the technical field of concrete, and in particular to concrete with wastewater purification function and a preparation method and application thereof. Background Art

[0002] At present, with the rapid development of my country's coal, metallurgy and other industries, the output of solid waste-based materials has caused accumulation. Solid waste-based materials refer to various dust, waste slag and other wastes generated in the production process of metal smelting, electricity, chemical industry and other industries. At present, the main way to deal with solid waste-based materials is simple stacking or landfill, which will cause a waste of land resources. Therefore, the resource utilization of industrial solid waste is an important development direction. At present, there are two basic methods for utilizing industrial solid waste. One is to extract valuable materials from solid waste-based materials through physical and chemical techniques, and the other is to use industrial solid waste as building materials, etc.

[0003] Sludge is a complex, heterogeneous solid separated from sewage. Every year, sewage treatment produces a large amount of sludge, which seriously pollutes land resources and the living environment. At present, the main methods for treating sludge are landfill, incineration, dumping into the sea and land use, but few people consider using it as an adsorption material, especially carbonizing sludge with biomass particles as adsorption particles, which has greater application prospects. However, the sludge may dry and shrink, which may reduce the adsorption efficiency.

[0004] Pedestrian road materials made from industrial solid waste still have certain environmental problems. Although the environmental properties of pedestrian road materials have been studied, the environmental risks of using industrial solid waste to make pedestrian road materials cannot be completely ruled out. The existing use of solid waste is prone to the risk of toxin leakage, which is a key factor hindering the large-scale use of industrial solid waste in pedestrian road materials. Summary of the invention

[0005] The main purpose of the present invention is to propose a concrete with wastewater purification function and its preparation method and application, aiming to apply industrial solid waste to pavement permeable materials, which not only solves the problem of solid waste recycling in industrial manufacturing, but also the prepared concrete with wastewater purification function has good mechanical properties and purification performance.

[0006] To achieve the above-mentioned purpose, the present invention proposes a concrete with wastewater purification function, the raw materials of which include adsorption particles, solid waste-based materials and alkaline activators, wherein the adsorption particles include biomass mixture and sludge; the solid waste-based materials include construction waste, titanium gypsum and asbestos tailings.

[0007] In one embodiment, the biomass mixture comprises nut shells and oyster shells; and / or,

[0008] The alkaline activator comprises sodium hydroxide; and / or,

[0009] The water content of the sludge is 75% to 85%; the average particle size of the sludge is not greater than 1 mm.

[0010] In one embodiment, in the adsorption particles, the mass ratio of the sludge to the biomass mixture is (70-80): (20-30); and / or,

[0011] In the adsorption particles, the adsorption particles include a biomass mixture and sludge, and the biomass mixture includes nut shells and oyster shells, wherein the mass ratio of the sludge, the nut shells and the oyster shells is (70-80): (10-15); (10-15); and / or,

[0012] In the solid waste-based material, the mass ratio of the construction waste, the titanium gypsum and the asbestos tailings is (40-70): (15-30): (15-30); and / or,

[0013] The amount of the alkali activator added is 1% to 5% of the solid waste-based material; and / or,

[0014] The mass ratio of the solid waste-based material, the adsorption particles and the alkali activator is (60-80): (20-40): (0.6-4).

[0015] The present invention provides a method for preparing concrete with wastewater purification function, comprising the following steps:

[0016] S1, mixing the sludge and the biomass mixture into particles to obtain initial adsorption particles;

[0017] S2, carbonizing the initial adsorption particles to obtain adsorption particles;

[0018] S3, drying and mixing the construction waste, titanium gypsum and asbestos tailings to obtain solid waste-based materials;

[0019] S4, mixing the solid waste-based material with the adsorption particles and the alkaline activator to obtain a mixed material;

[0020] S5. Add water to the mixture, shape it, solidify it, and then cure it to obtain concrete with wastewater purification function.

[0021] In one embodiment, before step S1, the process includes: drying nut shells and oyster shells at 50°C to 60°C to constant weight, grinding the nut shells and oyster shells through a 5 mm sieve, and finally stirring and mixing nut shells and oyster shells of equal mass at 100 to 400 r / min for 3 to 5 minutes to obtain a biomass mixture.

[0022] In one embodiment, in step S1, the particles are spherical particles, and the diameter of the spherical particles is 15 to 25 mm; and / or,

[0023] The mass ratio of the sludge to the biomass mixture is (70-80) to (20-30).

[0024] In one embodiment, in step S2, the carbonization temperature is 750-850° C.; and / or,

[0025] The carbonization time is 6 to 8 hours.

[0026] In one embodiment, in step S3,

[0027] The drying temperature is 100-110° C.; and / or,

[0028] The stirring speed is 600-1000 r / min; and / or,

[0029] The stirring time is 5 to 10 minutes.

[0030] In one embodiment, step S5 includes: adding water to the mixed material until the moisture content is 25% to 30%, pouring it into a mold for molding and curing, and then curing it under standard curing conditions for 7 to 28 days, wherein the standard conditions include: temperature of 18 to 22° C. and humidity of 95%.

[0031] The present invention also proposes an application of the above-mentioned concrete with wastewater purification function in wastewater treatment.

[0032] The present invention proposes a concrete with wastewater purification function, wherein the raw materials of the concrete with wastewater purification function include adsorption particles, solid waste-based materials and alkaline activators, wherein the adsorption particles include biomass mixture and sludge, and the sludge is used as a carrier for carrying the biomass mixture to be fused with the biomass mixture and carbonized to form adsorption particles, and the adsorption of the biomass mixture is used to adsorb wastewater containing a series of pollutants such as heavy metals flowing through the road surface; the solid waste-based materials include construction waste, titanium gypsum and asbestos tailings, and the three are mixed with water to produce a hydration reaction, which not only provides the necessary mechanical properties but also serves as a carrier of adsorption particles, and the alkaline substances in the construction waste, titanium gypsum and asbestos tailings can react with the heavy metals adsorbed by the adsorption particles to undergo ion exchange and successfully solidify the heavy metal pollutants to exert their purification performance, and by effectively utilizing solid waste materials, sludge and biomass mixtures, not only resources are saved, but also the pollution of heavy metals to the environment is reduced. The use of alkaline activators improves the early strength of concrete with wastewater purification function and enhances durability. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0034] Figure 1 This is a flow chart of concrete with wastewater purification function prepared according to an embodiment of the present invention.

[0035] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0036] To make the purpose, technical scheme and advantages of the embodiment of the present invention clearer, the technical scheme in the embodiment of the present invention will be described clearly and completely below. If the specific conditions are not specified in the embodiment, it is carried out according to the normal conditions or the conditions recommended by the manufacturer. If the reagents or instruments used do not specify the manufacturer, they are all conventional products that can be purchased commercially. In addition, the meaning of "and / or" appearing in the full text includes three parallel schemes, taking "A and / or B" as an example, including scheme A, or scheme B, or schemes that A and B meet at the same time. In addition, the technical schemes between the various embodiments can be combined with each other, but must be based on the ability of ordinary technicians in the field to achieve. When the combination of technical solutions is contradictory or cannot be achieved, it should be considered that the combination of such technical solutions does not exist, and is not within the scope of protection required by the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present invention.

[0037] In view of this, in order to achieve the above-mentioned purpose, the present invention proposes a concrete with wastewater purification function, the raw materials of which include adsorption particles, solid waste-based materials and alkaline activators, wherein the adsorption particles include biomass mixture and sludge; the solid waste-based materials include construction waste, titanium gypsum and asbestos tailings.

[0038] The present invention proposes a concrete with wastewater purification function, wherein the raw materials of the concrete with wastewater purification function include adsorption particles, solid waste-based materials and alkaline activators, wherein the adsorption particles include biomass mixture and sludge, and the sludge is used as a carrier for carrying the biomass mixture to be fused with the biomass mixture and carbonized to form adsorption particles, and the adsorption of the biomass mixture is used to adsorb wastewater containing a series of pollutants such as heavy metals flowing through the road surface; the solid waste-based materials include construction waste, titanium gypsum and asbestos tailings, and the three are mixed with water to produce a hydration reaction, which not only provides the necessary mechanical properties but also serves as a carrier of adsorption particles, and the alkaline substances in the construction waste, titanium gypsum and asbestos tailings can react with the heavy metals adsorbed by the adsorption particles to undergo ion exchange and successfully solidify the heavy metal pollutants to exert their purification performance, and by effectively utilizing solid waste materials, sludge and biomass mixtures, not only resources are saved, but also the pollution of heavy metals to the environment is reduced. The use of alkaline activators improves the early strength of concrete with wastewater purification function and enhances durability.

[0039] It should be noted that the solid waste-based materials of the present invention include construction waste, titanium gypsum and asbestos tailings. Specifically, titanium gypsum is mainly composed of CaSO4, which provides calcium ions, and asbestos tailings can provide SiO2 and Al2O3. These two groups of components can react with water to release hydroxide, thereby providing an alkaline environment to promote the entire hydration reaction to generate a gelling substance (Aft, CSH), thereby improving the mechanical properties.

[0040] In some embodiments of the present invention, the biomass mixture includes nut shells and oyster shells.

[0041] It should be noted that nutshells and oyster shells are agricultural and aquatic wastes, which are widely available and easily accessible, and are renewable resources. The use of these materials helps reduce dependence on traditional raw materials and promotes the recycling of waste. At the same time, nutshells and oyster shells have a natural porous structure, which enables them to absorb water and chemicals, increasing the specific surface area and adsorption performance of the adsorbent particles.

[0042] In some embodiments of the present invention, the alkaline activator includes sodium hydroxide. As an alkaline activator, sodium hydroxide can quickly activate the potential active substances in the solid waste material, promote the hydration reaction, and effectively improve the strength of the concrete with wastewater purification function.

[0043] In some embodiments of the present invention, the water content of the sludge is 75% to 85%; and the average particle size of the sludge is no greater than 1 mm.

[0044] It should be noted that the appropriate water content can provide good fluidity for the sludge. The water content of the sludge is 75% to 85%, so that it is easier to mix with the biomass mixture and form into particles. If the water content is too low, the sludge will become less viscous and difficult to form; if the water content is too high, it will affect the stability of the forming process. The particle size below 1mm allows the particles to be more evenly dispersed in concrete or other matrix materials, avoiding the uneven phenomenon caused by excessively large particles, which can ultimately improve the mechanical properties and durability of the concrete.

[0045] In some embodiments of the present invention, in the adsorption particles, the adsorption particles include a biomass mixture and sludge, and the biomass mixture includes nut shells and oyster shells, wherein the mass ratio of the sludge, the nut shells and the oyster shells is (70-80):(10-15); (10-15), specifically 70:10:10, 70:15:15 or 80:10:13, etc., and controlling the sludge and the biomass mixture at a suitable mass ratio ensures the balanced performance of the material.

[0046] In the solid waste-based materials, the mass ratio of the construction waste, the titanium gypsum and the asbestos tailings is (40-70): (15-30): (15-30), that is, the mass ratio of the construction waste, the titanium gypsum and the asbestos tailings can be 40:15:15, 70:30:30 or 50:20:20, etc. In the technical solution of the present invention, through the reasonable ratio of solid waste-based materials, the role of each material in the concrete with wastewater purification function is maximized, and the environmental protection benefits can be improved.

[0047] The mass ratio of the solid waste-based material, the adsorption particles and the alkali activator is (60-80): (20-40): (0.6-4), that is, the mass ratio of the solid waste-based material, the adsorption particles and the alkali activator can be in the range of 60:20:0.6, 80:20:0.6 or 70:25:3, etc. The mass ratio of the three is controlled to ensure that the alkali activator can effectively stimulate the potential activity of the solid waste-based material, and at the same time ensure that the adsorption particles play their reinforcing role in the concrete with wastewater purification function, so that the strength, adsorption performance and durability of the concrete with wastewater purification function can be improved, and at the same time, the amount of alkali activator can be reduced, reducing costs and environmental burdens.

[0048] The present invention provides a method for preparing concrete with wastewater purification function, as shown in the following Figure 1 As shown, the specific steps include:

[0049] S1, mixing the sludge and the biomass mixture into particles to obtain initial adsorption particles;

[0050] S2, carbonizing the initial adsorption particles to obtain adsorption particles;

[0051] S3, drying and mixing the construction waste, titanium gypsum and asbestos tailings to obtain solid waste-based materials;

[0052] S4, mixing the solid waste-based material with the adsorption particles and the alkaline activator to obtain a mixed material;

[0053] S5. Add water to the mixture, shape it, solidify it, and then cure it to obtain concrete with wastewater purification function.

[0054] In the technical solution of the present invention, the sludge and biomass are mixed to form initial adsorption particles and carbonized to increase the strength and adsorption capacity of the particles. After adding solid waste-based materials and alkali activators, water is added to form the particles, and the hydration reaction is promoted by curing, so that the concrete with wastewater purification function can reach the designed strength and density. The addition of solid waste materials and alkali activators can improve the comprehensive performance of the concrete with wastewater purification function and optimize the workability and durability of the concrete with wastewater purification function. In some embodiments of the present invention, before step S1, the process includes: drying nut shells and oyster shells at 50°C to 60°C to constant weight, grinding the nut shells and oyster shells through a 5mm sieve, and finally stirring and mixing nut shells and oyster shells of equal mass at 100-400r / min for 3-5min to obtain a biomass mixture. In this step, the drying step makes the moisture content of the nut shells and oyster shells constant to ensure the stability of subsequent mixing and molding; the grinding and mixing process ensures uniform particles and improves the dispersibility of the material. By controlling the drying temperature and mixing process, the uniformity of the biomass mixture is ensured, and the performance stability of the concrete with wastewater purification function is enhanced.

[0055] In some embodiments of the present invention, in step S1, the particles are spherical particles, and the diameter of the spherical particles is 15 to 25 mm. This is because spherical particles can make the mixed material have better fluidity and facilitate molding, and the uniform particle diameter can improve the mechanical properties of concrete. By controlling the particle shape and diameter, the formability and final mechanical properties of concrete are improved.

[0056] In some embodiments of the present invention, in step S2, the carbonization temperature is 750-850° C.; and / or the carbonization time is 6-8 hours.

[0057] Within this range of carbonization temperature and carbonization time, the selection ensures that the organic components of the adsorption particles are fully carbonized, thereby improving the hardness and adsorption capacity of the particles, while avoiding excessive carbonization that causes particle embrittlement.

[0058] In some embodiments of the present invention, in step S3,

[0059] The drying temperature is 100-110° C.; and / or,

[0060] The stirring speed is 600-1000 r / min; and / or,

[0061] The stirring time is 5 to 10 minutes. In the technical solution of the present invention, by controlling the stirring temperature, time and rotation speed, the sufficient mixing of materials is ensured, the separation of materials is avoided, and the uniformity, strength and durability of the concrete are improved.

[0062] In some embodiments of the present invention, step S5 includes: adding water to the mixed material until the moisture content is 25% to 30%, pouring it into a mold for molding and curing, and then curing it under standard curing conditions for 7 to 28 days, wherein the standard conditions include: temperature of 18 to 22°C and humidity of 95%.

[0063] By controlling the moisture content and curing conditions, the curing time of concrete is shortened and the early strength is improved. The standard conditions in the curing stage ensure the final performance of the concrete. Preferably, curing can be carried out in an environment of 60°C to promote the hydration reaction rate and enable the concrete to quickly reach early strength. Under standard curing conditions, the strength and durability of concrete with wastewater purification function gradually improves.

[0064] The present invention also provides an application of the concrete with wastewater purification function as described above, which is applied to wastewater treatment.

[0065] Specifically, the preparation steps of the concrete with wastewater purification function of the present invention are as follows:

[0066] Step 1: Grind nut shells and oyster shells through a 5 mm sieve and mix them evenly to obtain a biomass mixture.

[0067] Step 2: Sprinkle the biomass mixture evenly on the sludge in proportion and knead it to mix evenly, and divide it into several small balls with a diameter of 20 mm to obtain initial adsorption particles.

[0068] Step 3: The initial adsorption particles are burned and carbonized in a vacuum muffle furnace to obtain adsorption particles.

[0069] Step 4: Mix construction waste, titanium gypsum and asbestos tailings in proportion, and dry them in an oven to obtain solid waste-based materials.

[0070] Step 5: Add alkali activator and adsorption particles to the solid waste-based material, and place it in a 360-degree oscillator for oscillation and mixing to obtain a mixed material.

[0071] Step 6: Add pure water to the mixture until the moisture content is 25% to 30%, stir and mix for 10 minutes, then pour into a cube mold for compaction and high-temperature curing at 60°C. Then, cure for 7 to 28 days under standard curing conditions {(20±2)°C, humidity 95%} to obtain concrete with wastewater purification function.

[0072] The technical solution of the present invention is further described in detail below in conjunction with specific embodiments and drawings. It should be understood that the following embodiments are only used to explain the present invention and are not used to limit the present invention.

[0073] The experimental materials are as follows:

[0074] The sludge is S95 grade slag powder produced by Qingdao Zhongkuang Hongyuan, with a specific surface area of ​​410m 2 / kg;

[0075] The source of nut shells and oyster shells: solid waste discharged by a steel enterprise, whose components include CaO, SiO2, FeO and other oxides;

[0076] The construction waste comes from: It is taken from a construction waste plant in Wuhan City, and its components include SiO2, CaCO3, NaAlSiO8 and other substances;

[0077] Titanium gypsum was purchased from a certain titanium industry company in Southwest China. Its composition is CaSO4·2H2O and impurities of metal elements such as Fe, Al, and Mg;

[0078] Asbestos tailings: taken from an asbestos tailings pond, its composition includes SiO2, MgO and other oxides;

[0079] The fly ash is Class I fly ash, provided by Qingdao Municipal Engineering Group Concrete Engineering Co., Ltd.;

[0080] Example 1

[0081] Provided is a concrete with a wastewater purification function, wherein the raw materials of the concrete with a wastewater purification function include adsorption particles, solid waste-based materials and an alkaline activator, wherein the adsorption particles include a biomass mixture and sludge; the solid waste-based materials include construction waste, titanium gypsum and asbestos tailings, wherein the alkaline activator is sodium hydroxide, and the biomass mixture is nut shells and oyster shells;

[0082] The preparation steps of the concrete with wastewater purification function are as follows:

[0083] Step 1: Dry the nut shells and oyster shells at 50°C to constant weight, grind the nut shells and oyster shells through a 5 mm sieve, and finally stir and mix the nut shells and oyster shells of equal weight at 100 r / min for 3 minutes to obtain a biomass mixture;

[0084] Step 2: Sprinkle the biomass mixture evenly on the fresh sludge and knead it to mix evenly, and divide it into several small balls with a diameter of 20 mm, wherein the mass ratio of fresh sludge to biomass mixture is 7:3 to obtain initial adsorption particles;

[0085] Step 3: calcining the initial adsorption particles in a vacuum muffle furnace at 600° C. for 4 hours to obtain adsorption particles;

[0086] Step 4: Put the construction waste, titanium gypsum and asbestos tailings into an oven at 100° C. to dry, then mix them in a ratio of 40:30:30 by mass and stir them at 600 r / min for 5 minutes to obtain a solid waste-based material;

[0087] Step 5: adding an alkali activator to the solid waste-based material, wherein the amount of the alkali activator added is 1% of the total mass of the solid waste-based material, and then adding adsorption particles and placing in a 360-degree oscillator and oscillating and mixing at 600 r / min for 5 minutes, and making the mass ratio of the adsorption particles to the industrial solid waste carrier be 2:3, to obtain a mixed material;

[0088] Step 6: Add pure water to the mixture until the moisture content is 13%, stir and mix at 600r / min for 10 minutes, then pour into a cube mold for compaction and high-temperature curing at 60°C for 3 hours, and then cure under standard curing conditions {(20±2)°C, humidity 95%} for 7 to 28 days.

[0089] Example 2

[0090] Provided is a concrete with a wastewater purification function, wherein the raw materials of the concrete with a wastewater purification function include adsorption particles, solid waste-based materials and an alkaline activator, wherein the adsorption particles include a biomass mixture and sludge; the solid waste-based materials include construction waste, titanium gypsum and asbestos tailings, wherein the alkaline activator is sodium hydroxide, and the biomass mixture is nut shells and oyster shells;

[0091] The preparation steps of the concrete with wastewater purification function are as follows:

[0092] Step 1: Dry the nut shells and oyster shells at 50°C to constant weight, grind them through a 5 mm sieve, and finally stir and mix the nut shells and oyster shells of equal mass at 100 r / min for 3 minutes to obtain a biomass mixture.

[0093] Step 2: Sprinkle the biomass mixture evenly on the fresh sludge and knead it to mix evenly, and divide it into several small balls with a diameter of 20 mm. The mass ratio of fresh sludge to biomass mixture is 7:3, and the initial adsorption particles are obtained.

[0094] Step 3: The initial adsorption particles are calcined in a vacuum muffle furnace at 600° C. for 4.5 hours to obtain adsorption particles.

[0095] Step 4: Place the construction waste, titanium gypsum and asbestos tailings in an oven at 100° C. to dry, then mix them in a ratio of 40:30:30 by mass and stir at 600 r / min for 5 minutes to obtain solid waste-based materials.

[0096] Step 5: Add an alkali activator to the solid waste-based material, the amount of the alkali activator added is 2% of the total mass of the solid waste-based material, and then add adsorption particles and place them in a 360-degree oscillator and oscillate and mix at 600 r / min for 5 minutes, and make the mass ratio of the adsorption particles to the industrial solid waste carrier be 7:13 to obtain a mixed material.

[0097] Step 6: Add pure water to the mixture until the moisture content is 14%, stir and mix at 600r / min for 10 minutes, then pour into a cube mold for compaction and high-temperature curing at 60°C for 3 hours, and then cure under standard curing conditions {(20±2)°C, humidity 95%} for 7 to 28 days.

[0098] Example 3

[0099] Provided is a concrete with a wastewater purification function, wherein the raw materials of the concrete with a wastewater purification function include adsorption particles, solid waste-based materials and an alkaline activator, wherein the adsorption particles include a biomass mixture and sludge; the solid waste-based materials include construction waste, titanium gypsum and asbestos tailings, wherein the alkaline activator is sodium hydroxide, and the biomass mixture is nut shells and oyster shells;

[0100] The preparation steps of the concrete with wastewater purification function are as follows:

[0101] Step 1: Dry the nut shells and oyster shells at 55°C to constant weight, grind them through a 5 mm sieve, and finally stir and mix the nut shells and oyster shells of equal mass at 300 r / min for 5 minutes to obtain a biomass mixture.

[0102] Step 2: Sprinkle the biomass mixture evenly on the fresh sludge and knead it to mix evenly, and divide it into several small balls with a diameter of 20 mm. The mass ratio of fresh sludge to biomass mixture is 3:1, and initial adsorption particles are obtained.

[0103] Step 3: calcining the initial adsorption particles in a vacuum muffle furnace at 600° C. for 5 hours to obtain adsorption particles.

[0104] Step 4: Place the construction waste, titanium gypsum and asbestos tailings in an oven at 105° C. and dry them, then mix them in a ratio of 50:25:25 by mass and stir them at 800 r / min for 8 minutes to obtain solid waste-based materials.

[0105] Step 5: Add an alkali activator to the solid waste-based material, the amount of the alkali activator added is 3% of the total mass of the solid waste-based material, and then add the adsorption particles and place them in a 360-degree oscillator and oscillate and mix at 800r / min for 8 minutes, and make the mass ratio of the adsorption particles to the industrial solid waste carrier be 3:7 to obtain a mixed material.

[0106] Step 6: Add pure water to the mixture until the moisture content is 15%, stir and mix at 800r / min for 10 minutes, then pour into a cube mold for compaction and high-temperature curing at 60°C for 4 hours, and then cure under standard curing conditions {(20±2)°C, humidity 95%} for 7 to 28 days.

[0107] Example 4

[0108] Provided is a concrete with a wastewater purification function, wherein the raw materials of the concrete with a wastewater purification function include adsorption particles, solid waste-based materials and an alkaline activator, wherein the adsorption particles include a biomass mixture and sludge; the solid waste-based materials include construction waste, titanium gypsum and asbestos tailings, wherein the alkaline activator is sodium hydroxide, and the biomass mixture is nut shells and oyster shells;

[0109] The preparation steps of the concrete with wastewater purification function are as follows:

[0110] Step 1: Dry the nut shells and oyster shells at 55°C to constant weight, grind them through a 5 mm sieve, and finally stir and mix the nut shells and oyster shells of equal mass at 300 r / min for 5 minutes to obtain a biomass mixture.

[0111] Step 2: Sprinkle the biomass mixture evenly on the fresh sludge and knead it to mix evenly, and divide it into several small balls with a diameter of 20 mm. The mass ratio of fresh sludge to biomass mixture is 3:1, and initial adsorption particles are obtained.

[0112] Step 3: calcining the initial adsorption particles in a vacuum muffle furnace at 600° C. for 5.5 hours to obtain adsorption particles.

[0113] Step 4: Place the construction waste, titanium gypsum and asbestos tailings in an oven at 105° C. and dry them, then mix them in a ratio of 50:25:25 by mass and stir them at 800 r / min for 8 minutes to obtain solid waste-based materials.

[0114] Step 5: Add an alkali activator to the solid waste-based material, the amount of the alkali activator added is 4% of the total mass of the solid waste-based material, and then add adsorption particles and place them in a 360-degree oscillator and oscillate and mix at 800 r / min for 8 minutes, and make the mass ratio of the adsorption particles to the industrial solid waste carrier be 1:3 to obtain a mixed material.

[0115] Step 6: Add pure water to the mixture until the moisture content is 16%, stir and mix at 800r / min for 10 minutes, then pour into a cube mold for compaction and high-temperature curing at 60°C for 4 hours, and then cure under standard curing conditions {(20±2)°C, humidity 95%} for 7 to 28 days.

[0116] Example 5

[0117] Provided is a concrete with a wastewater purification function, wherein the raw materials of the concrete with a wastewater purification function include adsorption particles, solid waste-based materials and an alkaline activator, wherein the adsorption particles include a biomass mixture and sludge; the solid waste-based materials include construction waste, titanium gypsum and asbestos tailings, wherein the alkaline activator is sodium hydroxide, and the biomass mixture is nut shells and oyster shells;

[0118] The preparation steps of the concrete with wastewater purification function are as follows:

[0119] Step 1: Dry the nut shells and oyster shells at 60°C to constant weight, grind them through a 5 mm sieve, and finally stir and mix the nut shells and oyster shells of equal mass at 400 r / min for 5 minutes to obtain a biomass mixture.

[0120] Step 2: Sprinkle the biomass mixture evenly on the fresh sludge and knead it to mix evenly, and divide it into several small balls with a diameter of 20 mm. The mass ratio of fresh sludge to biomass mixture is 4:1, and initial adsorption particles are obtained.

[0121] Step 3: Sinter the initial adsorption particles in a vacuum muffle furnace at 600° C. for 6 hours to obtain adsorption particles.

[0122] Step 4: Place the construction waste, titanium gypsum and asbestos tailings in an oven at 110° C. and dry them, then mix them in a mass ratio of 70:15:15 and stir them at 1000 r / min for 10 minutes to obtain solid waste-based materials.

[0123] Step 5: Add an alkali activator to the solid waste-based material, the amount of the alkali activator added is 5% of the total mass of the solid waste-based material, and then add adsorption particles and place them in a 360-degree oscillator and oscillate and mix at 1000r / min for 10 minutes, and make the mass ratio of the adsorption particles to the industrial solid waste carrier be 1:4 to obtain a mixed material.

[0124] Step 6: Add pure water to the mixture until the moisture content is 17%, stir and mix at 1000r / min for 10 minutes, then pour into a cube mold for compaction and high-temperature curing at 60°C for 5 hours, and then cure under standard curing conditions {(20±2)°C, humidity 95%} for 7 to 28 days.

[0125] Example 6

[0126] Provided is a concrete with a wastewater purification function, wherein the mass ratio of the construction waste, the titanium gypsum and the asbestos tailings is set to 70:30:30, and the rest is the same as in Example 1.

[0127] Example 7

[0128] Provided is a concrete with a wastewater purification function, wherein the mass ratio of the construction waste, the titanium gypsum and the asbestos tailings is set to 40:10:10, and the rest is the same as in Example 1.

[0129] Comparative Example 1

[0130] Provided is a concrete with wastewater purification function, in which the biomass mixture is replaced with straw, and the rest is the same as in Example 1.

[0131] Comparative Example 2

[0132] Provided is a concrete having a wastewater purification function, wherein the adsorption particles only include a biomass mixture, and the rest is the same as in Example 1.

[0133] Comparative Example 3

[0134] Provided is a concrete with wastewater purification function, wherein the solid waste substrate material is replaced with construction waste, phosphogypsum, and blast furnace slag commonly used on the market, and the rest is the same as in Example 1.

[0135] Performance Testing

[0136] The concrete with wastewater purification function prepared in the above Examples 1 to 7 and Comparative Examples 1 to 3 was tested for performance, wherein the mechanical properties test adopted the "Technical Specification for Concrete Pavement with Wastewater Purification Function of Permeable Cement" (CJJ / T135-2009), and the test results are shown in Table 1. The leaching toxicity test was carried out in accordance with the "Solid Waste Leaching Toxicity Leaching Method Horizontal Oscillation Method" (HJ 557-2010) and the "Comprehensive Sewage Discharge Standard" (GB 8978-1996), and the leaching toxicity identification values ​​of inorganic elements in the leachate are shown in Table 2.

[0137] Table 1 Mechanical properties of concrete with wastewater purification function

[0138]

[0139] Table 2 Identification values ​​of leaching toxicity of inorganic elements in the leachate of industrial waste residue grade permeable concrete materials with wastewater purification function

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[0142] It should be noted that the water permeability coefficient refers to the ability of water to pass through a material (such as soil or concrete with wastewater purification function) under a certain pressure. The larger the water permeability coefficient, the stronger the water permeability of the material. For building materials, the water permeability coefficient helps to evaluate the waterproof or drainage performance of the material;

[0143] The compressive strength loss rate after freeze-thaw cycles refers to the loss ratio of the material's compressive strength after a certain number of freeze-thaw cycles (repeated freezing and thawing). This index is used to evaluate the durability of materials in cold areas. A lower loss rate indicates that the material maintains better mechanical properties under repeated freeze-thaw cycles and is suitable for use in cold environments.

[0144] Compressive strength refers to the maximum stress value of a material against compression damage. A higher compressive strength means that the material can bear a larger load without damage.

[0145] Flexural strength refers to the ability of a material to resist damage under bending load, also known as bending strength, and is usually used to evaluate the toughness of a material and its ability to resist crack propagation;

[0146] The concentration limit is based on the national standard requirements of "Comprehensive Wastewater Discharge Standard" (GB 8978-1996).

[0147] As shown in Table 1, Comparative Examples 1 and 2 are the same as Example 1 in terms of solid waste-based materials. When only the adsorption part of the materials is changed, the mechanical properties of the example are better. Comparative Example 3 uses phosphogypsum and blast furnace slag to replace the original titanium gypsum and asbestos tailings, so the water permeability coefficient, the loss rate of compressive strength after freeze-thaw cycles, the compressive strength and the flexural strength are worse than those of Example 1. The main reason is that in addition to calcium sulfate, the composition of phosphogypsum also contains a series of impurities such as incompletely decomposed phosphate ore and residual phosphoric acid, which are difficult to completely remove, thus affecting the hydration process of the gelling material and resulting in weak mechanical properties.

[0148] It can be seen from Table 2 that: in Comparative Example 1, the biomass mixture is replaced with straw. Since the adsorption performance of straw is not as good as the superposition of nut shells and oyster shells, the concentration of each metal in the leaching toxicity experiment will be higher than that in Example 1; in Comparative Example 2, since there is no sludge, the adsorption area of ​​biochar is reduced and the adsorption capacity is weakened, the concentration of each metal in the leaching toxicity experiment will be higher than that in Example 1; in Comparative Example 3, since the solid waste-based materials are replaced with phosphogypsum and blast furnace slag, the impurities in phosphogypsum are difficult to remove, resulting in the concentration of each metal in the leaching toxicity being higher than that in Example 1.

[0149] The above are only preferred embodiments of the present invention, and do not limit the patent scope of the present invention. For those skilled in the art, the present invention may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the patent protection scope of the present invention.

Claims

1. A concrete with wastewater purification function, characterized in that: The raw materials of the concrete with wastewater purification function include adsorption particles, solid waste-based materials and alkaline activators, wherein the adsorption particles include biomass mixture and sludge; the solid waste-based materials include construction waste, titanium gypsum and asbestos tailings.

2. The concrete with wastewater purification function according to claim 1, characterized in that: The biomass mixture includes nut shells and oyster shells; and / or, The alkaline activator comprises sodium hydroxide; and / or, The water content of the sludge is 75-85%, and the average particle size of the sludge is no more than 1 mm.

3. The concrete with wastewater purification function according to claim 1, characterized in that: In the adsorption particles, the mass ratio of the sludge to the biomass mixture is (70-80): (20-30); and / or, In the adsorption particles, the adsorption particles include a biomass mixture and sludge, and the biomass mixture includes nut shells and oyster shells, wherein the mass ratio of the sludge, the nut shells and the oyster shells is (70-80): (10-15); (10-15); and / or, In the solid waste-based material, the mass ratio of the construction waste, the titanium gypsum and the asbestos tailings is (40-70): (15-30): (15-30); and / or, The amount of the alkali activator added is 1% to 5% of the solid waste-based material; and / or, The mass ratio of the solid waste-based material, the adsorption particles and the alkali activator is (60-80): (20-40): (0.6-4).

4. A method for preparing concrete with wastewater purification function as claimed in any one of claims 1 to 3, characterized in that: The following steps are involved: S1, mixing the sludge and the biomass mixture into particles to obtain initial adsorption particles; S2, carbonizing the initial adsorption particles to obtain adsorption particles; S3, drying and mixing the construction waste, titanium gypsum and asbestos tailings to obtain solid waste-based materials; S4, mixing the solid waste-based material with the adsorption particles and the alkaline activator to obtain a mixed material; S5. Add water to the mixture, shape it, solidify it, and then cure it to obtain concrete with wastewater purification function.

5. The method for preparing concrete with wastewater purification function according to claim 4, characterized in that: Before step S1, the process includes: drying the nut shells and oyster shells at 50° C. to 60° C. to constant weight, grinding the nut shells and oyster shells through a 5 mm sieve, and finally stirring and mixing the nut shells and oyster shells of equal mass at 100 to 400 r / min for 3 to 5 minutes to obtain a biomass mixture.

6. The method for preparing concrete with wastewater purification function according to claim 4, characterized in that: In step S1, the particles are spherical particles, and the diameter of the spherical particles is 15 to 25 mm.

7. The method for preparing concrete with wastewater purification function according to claim 4, characterized in that: In step S2, the carbonization temperature is 750-850° C.; and / or, The carbonization time is 6 to 8 hours.

8. The method for preparing concrete with wastewater purification function according to claim 4, characterized in that: In step S3, The drying temperature is 100-110° C.; and / or, The stirring speed is 600-1000 r / min; and / or, The stirring time is 5 to 10 minutes.

9. The method for preparing concrete with wastewater purification function according to claim 4, characterized in that: Step S5 includes: After adding water to the mixed material until the moisture content is 25% to 30%, pour it into a mold for molding and curing, and then cure it under standard curing conditions for 7 to 28 days, wherein the standard conditions include: temperature of 18 to 22°C and humidity of 95%.

10. Use of the concrete with wastewater purifying function as claimed in any one of claims 1 to 3 or the concrete with wastewater purifying function obtained by the preparation method of the concrete with wastewater purifying function as claimed in any one of claims 4 to 9 in wastewater treatment.

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