A method for functionalizing wastewater glass sand and alkali-activated slag concrete prepared therefrom

Abstract

The present invention discloses a method for functionalizing wastewater glass sand and alkali-activated slag concrete prepared therefrom, which is characterized in that the method comprises the following steps: (1) mixing cement and water, standing for a certain period of time, and taking out the supernatant as a saturated cement solution; (2) adding tartaric acid to the saturated cement solution, and heating the solution to a certain temperature; (3) adding wastewater glass sand thereto, stirring and standing for a certain period of time, filtering and drying, and obtaining activated wastewater glass sand. The present invention utilizes a hot solution to cause the water glass coating layer on the surface of the wastewater glass sand to dissolve, utilizes calcium ions in the saturated cement solution to react with the dissolved water glass to form calcium silicate, and activates the wastewater glass sand through the functional groups of tartaric acid, thereby achieving the purpose of functionalizing the wastewater glass sand. The present invention is simple to operate and low in cost, and has broad application prospects in the context of shortage of raw materials in the building materials market.

Description

Technical field:

[0001] The invention relates to a wastewater glass molding sand functionalization method and alkali-activated slag concrete prepared therefrom, and belongs to the field of wastewater glass molding sand recycling. Background technology:

[0002] In the casting process, the casting shell is the key to producing qualified castings. It is mainly composed of molding sand and binder. The preparation of the shell is affected by many factors such as cost, operating environment, pollution and casting quality requirements. In recent years, more and more foundries have chosen water glass as a sand binder to prepare casting shells. This type of shell not only has the advantages of low cost, good operating environment and simple process, but also has less pollution than resin binders. However, after the strong heat of metal casting, the shell will have significant changes in performance and is not suitable for continued use and needs to be discarded, thereby generating a large amount of waste sand. Generally, the production of 1 ton of castings will generate 3 to 4 tons of waste sand. Except for 20 to 30% of the sand that can be reused once or multiple times after special processing, the rest of the waste sand is often directly dumped in the environment or landfilled, which not only occupies land and pollutes the environment, but also significantly increases the environmental protection cost of the enterprise. Therefore, how to effectively dispose of and reuse waste sand has become a key issue that needs to be solved for the sustainable development of the foundry industry.

[0003] At present, sand and gravel resources are extremely scarce in the construction industry, and the price is rising day by day. Using waste sand as fine aggregate for concrete can not only completely dispose of it and solve the environmental problems related to it, but also increase the added value of waste sand and generate significant economic benefits. However, wastewater glass sand is difficult to bond and is incompatible with cement, which is a key problem in its current application. The root cause is that the wastewater glass sand particles are coated with a layer of hardened water glass and silica gel. In the cement-based system, this layer of water glass and silica gel will dissolve and release into the pore solution, affecting the cement hydration process, lowering the solution pH, and destroying the stable environment of the hydration products, causing the mechanical properties of cement-based materials to deteriorate significantly and the durability to be poor. Summary of the invention:

[0004] The purpose of the present invention is to provide a method for functionalizing wastewater glass sand and alkali-activated slag concrete prepared therefrom. The present invention utilizes complex calcium to be adsorbed on the surface of wastewater glass sand by hot solution solidification, and induces hydration of slag in alkali-activated slag concrete through the ion capture ability of the chelate, thereby promoting hydration of slag, which not only effectively improves the performance of wastewater glass sand, but also improves the strength of alkali-activated concrete. To achieve the above purpose, the present invention discloses the following technical scheme.

[0005] In a first aspect, the present invention discloses a functionalized material containing tartaric acid and calcium as wastewater glass molding sand.

[0006] Furthermore, the wastewater glass sand functionalization method comprises the following steps:

[0007] (1) Mix cement and water, let them stand for a certain period of time, and then take out the supernatant as a saturated cement solution;

[0008] (2) adding tartaric acid to a saturated cement solution and heating the solution to a certain temperature;

[0009] (3) Add wastewater glass sand, stir, let stand for a certain period of time, filter and dry, and obtain activated wastewater glass sand.

[0010] Furthermore, in step (1), the cement is commercially available ordinary Portland cement, including at least one of strength grades 52.5, 42.5 and 32.5.

[0011] Furthermore, in step (1), the mass ratio of cement to water is 0.001:1 to 0.005:1.

[0012] Furthermore, in step (1), the standing time is 2 to 24 hours.

[0013] Furthermore, in step (2), the tartaric acid is at least one of industrial pure and analytical pure.

[0014] Furthermore, in step (2), the mass ratio of the tartaric acid to the saturated cement solution is 0.001:1 to 0.015:1.

[0015] Furthermore, in step (2), the solution is heated to a temperature of 50 to 80°C.

[0016] Furthermore, in step (3), the waste water glass molding sand is foundry molding sand prepared using water glass as a main binder, which is waste powder after being used multiple times.

[0017] Furthermore, in step (3), the mass ratio of the wastewater glass sand to the hot solution in step (2) is 0.1:1 to 0.5:1.

[0018] Furthermore, in step (3), the standing time is 2 to 24 hours.

[0019] In a second aspect, the present invention provides an alkali-activated slag concrete, comprising the following components in parts by weight: 50 to 175 parts of activated wastewater glass sand, 120 to 460 parts of slag, 12 to 86 parts of fly ash, 75 to 265 parts of sand, 160 to 360 parts of gravel, 26 to 131 parts of alkaline activator, and 20 to 160 parts of water.

[0020] Furthermore, the alkaline activator is NaOH, water glass, Na 2 S04 、Na 2 CO 3 , MgO, lime, and KOH.

[0021] Furthermore, the slag is commercially available blast furnace slag, and preferably, the blast furnace slag is S95 grade or above blast furnace slag, and the fineness is 200 mesh accounting for more than 90%.

[0022] Furthermore, the fly ash is commercially available fly ash. Preferably, the fly ash is grade 2 or above, and the fineness of the fly ash is 200 mesh, accounting for more than 90%.

[0023] Compared with the prior art, the present invention has at least the following beneficial effects:

[0024] (1) The global annual output of foundry waste sand is about 100 million tons, which is difficult to utilize and has become a serious burden on enterprises and the environment. Concrete is the most widely used artificial building material and a major disposal material for solid waste. Using foundry waste sand to prepare concrete has important economic and environmental significance. The present invention is simple to operate and low in cost. It has broad application prospects in the context of shortage of raw materials in the building materials market.

[0025] (2) The present invention proposes a method for functionalizing wastewater glass sand and alkali-activated slag concrete prepared therefrom. The wastewater glass sand is immersed in a saturated hot cement solution, so that the water glass coating layer on the surface of the wastewater glass sand can be dissolved and react with calcium ions in the saturated cement solution to form calcium silicate, thereby repairing and reinforcing the surface of the wastewater glass sand. On the other hand, the tartaric acid in the saturated hot cement solution can react with the alkaline water glass dissolving layer of the wastewater glass sand, thereby adhering the tartaric acid functional groups with strong hydrophilicity and chelating ability to the surface of the wastewater glass sand, thereby achieving the purpose of functionalizing the wastewater glass sand.

[0026] (3) Tartaric acid has a strong calcium ion chelating ability. In alkali-activated concrete, the tartaric acid group can capture calcium ions in the concrete pore solution, reduce the calcium ion concentration of the pore solution, and then induce the slag to accelerate the hydration equilibrium solution ion concentration, which plays a role in accelerating hydration. In addition, the chelate of tartaric acid and calcium ions can also form crystal nuclei for the formation of hydration products in the pore solution, accelerate the deposition of hydration products on the surface of its particles, and promote the formation of hydration products. Therefore, the prepared alkali-activated concrete can have a denser pore structure and higher strength. Description of the drawings:

[0027] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention, and the exemplary embodiments of the present invention and their description are used to explain the present invention, and do not constitute an improper limitation of the present invention.

[0028] Figure 1 This is the interface diagram of the alkali-activated concrete wastewater glass sand prepared in the following Example 1.

[0029] Figure 2 This is the interface diagram of the alkali-activated concrete wastewater glass sand prepared in the following Example 2.

[0030] Figure 3 This is the interface diagram of the alkali-activated concrete wastewater glass sand prepared in the following Example 3.

[0031] Figure 4 This is the interface diagram of the alkali-activated concrete wastewater glass sand prepared in the following Example 4.

[0032] Figure 5 This is the interface diagram of the alkali-activated concrete wastewater glass sand prepared in the following Example 5.

[0033] Figure 6 This is the interface diagram of the alkali-activated concrete wastewater glass sand prepared in the following Example 6.

[0034] Figure 7 This is the interface diagram of the alkali-activated concrete wastewater glass sand prepared in the following Example 7.

[0035] Figure 8 This is the interface diagram of the alkali-activated concrete wastewater glass sand prepared in the following Example 8.

[0036] Fig. 9 This is the interface diagram of the alkali-activated concrete wastewater glass sand prepared in the following Example 9. Specific implementation method:

[0037] The present invention is further described below in conjunction with specific examples, which are only used to illustrate the present invention and are not used to limit the scope of the present invention. The preferred implementation methods and materials described herein are only for demonstration purposes. It should be noted that all professional and scientific terms used in the present invention have the same meanings as those familiar to those skilled in the art, unless otherwise defined.

[0038] In addition, the reagents or raw materials used in the present invention can be purchased through conventional channels. Unless otherwise specified, the reagents or raw materials used in the present invention are used in accordance with conventional methods in the art or in accordance with product instructions. The method for preparing carbonized concrete for controlling the crystal form of carbonized products and the preparation technology of low-carbon concrete of the present invention are further described in conjunction with the following specific embodiments.

[0039] In order to make the present invention easier to understand and the technical solutions and advantages clearer, the present invention is further described in detail below in conjunction with the embodiments and accompanying drawings. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. The specific experimental methods not mentioned in the following examples are usually carried out according to conventional experimental methods.

[0040] Example 1

[0041] 1. A method for functionalizing wastewater glass sand, comprising the following steps:

[0042] (1) Mix 42.5% ordinary Portland cement and water in a mass ratio of 0.003:1, let stand for 6 h, and take out the supernatant as the saturated cement solution.

[0043] (2) Add tartaric acid at a rate of 0.005 of the mass of the saturated cement solution and heat the solution to 60°C.

[0044] (3) Mixing the wastewater glass molding sand and the solution of step (2) in a mass ratio of 0.2:1, stirring and standing for 6 hours, filtering and drying, and obtaining activated wastewater glass molding sand.

[0045] 2. An alkali-activated slag concrete comprising the following steps:

[0046] (I) Prepare raw materials: 150 parts of the activated wastewater glass sand prepared in this embodiment, 245 parts of S95 grade slag, 32 parts of fly ash, 126 parts of sand, 256 parts of gravel, 27 parts of NaOH, and 115 parts of water.

[0047] (II) Mix the above raw materials and stir them evenly to obtain alkali-activated concrete. Pour the alkali-activated concrete into a 100mm×100mm×100mm mold and place it in a standard curing room with a temperature of 20±2°C and a relative humidity greater than 95% for curing for 1 day. Then remove the obtained alkali-activated concrete test block from the mold and continue to cure it to the age of 3 days, 7 days, and 28 days. Use a press to test the compressive strength of alkali-activated concrete test blocks of different ages. The results are shown in Table 1.

[0048] Example 2

[0049] 1. A method for functionalizing wastewater glass sand, comprising the following steps:

[0050] (1) Mix 42.5% ordinary Portland cement and water in a mass ratio of 0.005:1, let stand for 6 h, and take out the supernatant as the saturated cement solution.

[0051] (2) Add tartaric acid at a rate of 0.005 of the mass of the saturated cement solution and heat the solution to 60°C.

[0052] (3) Mixing the wastewater glass molding sand and the solution of step (2) in a mass ratio of 0.2:1, stirring and standing for 6 hours, filtering and drying, and obtaining activated wastewater glass molding sand.

[0053] 2. An alkali-activated slag concrete comprising the following steps:

[0054] (I) Prepare raw materials: 150 parts of the activated wastewater glass sand prepared in this embodiment, 245 parts of S95 grade slag, 32 parts of fly ash, 126 parts of sand, 256 parts of gravel, 27 parts of NaOH, and 115 parts of water.

[0055] (II) Mix the above raw materials and stir them evenly to obtain alkali-activated concrete. Pour the alkali-activated concrete into a 100mm×100mm×100mm mold and place it in a standard curing room with a temperature of 20±2°C and a relative humidity greater than 95% for curing for 1 day. Then remove the obtained alkali-activated concrete test block from the mold and continue to cure it to the age of 3 days, 7 days, and 28 days. Use a press to test the compressive strength of alkali-activated concrete test blocks of different ages. The results are shown in Table 1.

[0056] Example 3

[0057] 1. A method for functionalizing wastewater glass sand, comprising the following steps:

[0058] (1) Mix 42.5% ordinary Portland cement and water in a mass ratio of 0.003:1, let stand for 6 h, and take out the supernatant as the saturated cement solution.

[0059] (2) Add tartaric acid at a rate of 0.01 of the mass of the saturated cement solution and heat the solution to 60°C.

[0060] (3) Mixing the wastewater glass molding sand and the solution of step (2) in a mass ratio of 0.2:1, stirring and standing for 6 hours, filtering and drying, and obtaining activated wastewater glass molding sand.

[0061] 2. An alkali-activated slag concrete comprising the following steps:

[0062] (I) Prepare raw materials: 150 parts of the activated wastewater glass sand prepared in this embodiment, 245 parts of S95 grade slag, 32 parts of fly ash, 126 parts of sand, 256 parts of gravel, 27 parts of NaOH, and 115 parts of water.

[0063] (II) Mix the above raw materials and stir them evenly to obtain alkali-activated concrete. Pour the alkali-activated concrete into a 100mm×100mm×100mm mold and place it in a standard curing room with a temperature of 20±2°C and a relative humidity greater than 95% for curing for 1 day. Then remove the obtained alkali-activated concrete test block from the mold and continue to cure it to the age of 3 days, 7 days, and 28 days. Use a press to test the compressive strength of alkali-activated concrete test blocks of different ages. The results are shown in Table 1.

[0064] Example 4

[0065] 1. A method for functionalizing wastewater glass sand, comprising the following steps:

[0066] (1) Mix 42.5% ordinary Portland cement and water in a mass ratio of 0.003:1, let stand for 6 h, and take out the supernatant as the saturated cement solution.

[0067] (2) Add tartaric acid at a rate of 0.005 of the mass of the saturated cement solution and heat the solution to 60°C.

[0068] (3) Mixing the wastewater glass molding sand and the solution of step (2) in a mass ratio of 0.2:1, stirring and standing for 6 hours, filtering and drying, and obtaining activated wastewater glass molding sand.

[0069] 2. An alkali-activated slag concrete comprising the following steps:

[0070] (I) Prepare raw materials: 150 parts of the activated waste water glass molding sand prepared in this embodiment, 245 parts of S95 grade slag, 32 parts of fly ash, 126 parts of sand, 256 parts of gravel, 27 parts of water glass, and 115 parts of water.

[0071] (II) Mix the above raw materials and stir them evenly to obtain alkali-activated concrete. Pour the alkali-activated concrete into a 100mm×100mm×100mm mold and place it in a standard curing room with a temperature of 20±2°C and a relative humidity greater than 95% for curing for 1 day. Then remove the obtained alkali-activated concrete test block from the mold and continue to cure it to the age of 3 days, 7 days, and 28 days. Use a press to test the compressive strength of alkali-activated concrete test blocks of different ages. The results are shown in Table 1.

[0072] Example 5

[0073] 1. A method for functionalizing wastewater glass sand, comprising the following steps:

[0074] (1) Mix tartaric acid and water in a mass ratio of 0.005:1 and heat to 60°C.

[0075] (2) Mixing the wastewater glass molding sand with the solution of step (1) in a mass ratio of 0.2:1, stirring and standing for 6 hours, filtering and drying, and obtaining the wastewater glass molding sand.

[0076] 2. An alkali-activated slag concrete comprising the following steps:

[0077] (I) Prepare raw materials: 150 parts of the activated wastewater glass sand prepared in this embodiment, 245 parts of S95 grade slag, 32 parts of fly ash, 126 parts of sand, 256 parts of gravel, 27 parts of NaOH, and 115 parts of water.

[0078] (II) Mix the above raw materials and stir them evenly to obtain alkali-activated concrete. Pour the alkali-activated concrete into a 100mm×100mm×100mm mold and place it in a standard curing room with a temperature of 20±2°C and a relative humidity greater than 95% for curing for 1 day. Then remove the obtained alkali-activated concrete test block from the mold and continue to cure it to the age of 3 days, 7 days, and 28 days. Use a press to test the compressive strength of alkali-activated concrete test blocks of different ages. The results are shown in Table 1.

[0079] Example 6

[0080] 1. A method for functionalizing wastewater glass sand, comprising the following steps:

[0081] (1) Mix 42.5% ordinary Portland cement and water in a mass ratio of 0.003:1, let stand for 6 h, and take out the supernatant as the saturated cement solution.

[0082] (2) Heat the solution to 60°C.

[0083] (3) Mixing the wastewater glass molding sand and the solution of step (2) in a mass ratio of 0.2:1, stirring and standing for 6 hours, filtering and drying, and obtaining activated wastewater glass molding sand.

[0084] 2. An alkali-activated slag concrete comprising the following steps:

[0085] (I) Prepare raw materials: 150 parts of the activated wastewater glass sand prepared in this embodiment, 245 parts of S95 grade slag, 32 parts of fly ash, 126 parts of sand, 256 parts of gravel, 27 parts of NaOH, and 115 parts of water.

[0086] (II) Mix the above raw materials and stir them evenly to obtain alkali-activated concrete. Pour the alkali-activated concrete into a 100mm×100mm×100mm mold and place it in a standard curing room with a temperature of 20±2°C and a relative humidity greater than 95% for curing for 1 day. Then remove the obtained alkali-activated concrete test block from the mold and continue to cure it to the age of 3 days, 7 days, and 28 days. Use a press to test the compressive strength of alkali-activated concrete test blocks of different ages. The results are shown in Table 1.

[0087] Example 7

[0088] 1. A method for functionalizing wastewater glass sand, comprising the following steps:

[0089] (1) Mix 42.5% ordinary Portland cement and water in a mass ratio of 0.003:1, let stand for 6 h, and take out the supernatant as the saturated cement solution.

[0090] (2) Add tartaric acid at a rate of 0.005 of the mass of the saturated cement solution and heat the solution to 80°C.

[0091] (3) Mixing the wastewater glass molding sand and the solution of step (2) in a mass ratio of 0.2:1, stirring and standing for 6 hours, filtering and drying, and obtaining activated wastewater glass molding sand.

[0092] 2. An alkali-activated slag concrete comprising the following steps:

[0093] (I) Prepare raw materials: 150 parts of the activated wastewater glass sand prepared in this embodiment, 245 parts of S95 grade slag, 32 parts of fly ash, 126 parts of sand, 256 parts of gravel, 27 parts of NaOH, and 115 parts of water.

[0094] (II) Mix the above raw materials and stir them evenly to obtain alkali-activated concrete. Pour the alkali-activated concrete into a 100mm×100mm×100mm mold and place it in a standard curing room with a temperature of 20±2°C and a relative humidity greater than 95% for curing for 1 day. Then remove the obtained alkali-activated concrete test block from the mold and continue to cure it to the age of 3 days, 7 days, and 28 days. Use a press to test the compressive strength of alkali-activated concrete test blocks of different ages. The results are shown in Table 1.

[0095] Example 8

[0096] 1. A method for functionalizing wastewater glass sand, comprising the following steps:

[0097] (1) Mix 42.5% ordinary Portland cement and water in a mass ratio of 0.003:1, let stand for 6 h, and take out the supernatant as the saturated cement solution.

[0098] (2) Add tartaric acid at a rate of 0.005 of the mass of the saturated cement solution and heat the solution to 60°C.

[0099] (3) Mixing the wastewater glass sand and the solution of step (2) in a mass ratio of 0.5:1, stirring and standing for 6 hours, filtering and drying, and obtaining activated wastewater glass sand.

[0100] 2. An alkali-activated slag concrete comprising the following steps:

[0101] (I) Prepare raw materials: 150 parts of the activated wastewater glass sand prepared in this embodiment, 245 parts of S95 grade slag, 32 parts of fly ash, 126 parts of sand, 256 parts of gravel, 27 parts of NaOH, and 115 parts of water.

[0102] (II) Mix the above raw materials and stir them evenly to obtain alkali-activated concrete. Pour the alkali-activated concrete into a 100mm×100mm×100mm mold and place it in a standard curing room with a temperature of 20±2°C and a relative humidity greater than 95% for curing for 1 day. Then remove the obtained alkali-activated concrete test block from the mold and continue to cure it to the age of 3 days, 7 days, and 28 days. Use a press to test the compressive strength of alkali-activated concrete test blocks of different ages. The results are shown in Table 1.

[0103] Example 9

[0104] 1. A method for functionalizing wastewater glass sand, comprising the following steps:

[0105] (1) Mix 42.5% ordinary Portland cement and water in a mass ratio of 0.003:1, let stand for 3 h, and take out the supernatant as the saturated cement solution.

[0106] (2) Add tartaric acid at a rate of 0.005 of the mass of the saturated cement solution and heat the solution to 60°C.

[0107] (3) Mixing the wastewater glass molding sand and the solution of step (2) in a mass ratio of 0.2:1, stirring and standing for 6 hours, filtering and drying, and obtaining activated wastewater glass molding sand.

[0108] 2. An alkali-activated slag concrete comprising the following steps:

[0109] (I) Prepare raw materials: 150 parts of the activated wastewater glass sand prepared in this embodiment, 245 parts of S95 grade slag, 32 parts of fly ash, 126 parts of sand, 256 parts of gravel, 27 parts of NaOH, and 115 parts of water.

[0110] (II) Mix the above raw materials and stir them evenly to obtain alkali-activated concrete. Pour the alkali-activated concrete into a 100mm×100mm×100mm mold and place it in a standard curing room with a temperature of 20±2°C and a relative humidity greater than 95% for curing for 1 day. Then remove the obtained alkali-activated concrete test block from the mold and continue to cure it to the age of 3 days, 7 days, and 28 days. Use a press to test the compressive strength of alkali-activated concrete test blocks of different ages. The results are shown in Table 1.

[0111] Performance testing and structural characterization

[0112] 1. The alkali-activated concrete prepared in Examples 1 to 9 was observed under a FlexSEM1000 scanning electron microscope. The results are as shown in the attached specification. Figures 1 to 9 As shown. Figures 1 to 4 It can be seen that the connection between the wastewater glass sand and the alkali-activated concrete paste is very tight, the pores are small, and the overall interface is strong. In addition, a large number of granular hydration products grow at the interface of the wastewater glass sand and are scattered in the interface area. This shows that after activation with tartaric acid, the formation of hydration products at the interface can be promoted, further strengthening the interface. Figures 5 to 9 It can be seen that the interface of the wastewater glass sand has obvious pores, large cracks, and the interface is obviously weak. This shows that the technology proposed by the present invention can better solve the problem of weak interface of wastewater glass sand and will significantly improve the mechanical properties of alkali-activated concrete mixed with wastewater glass sand.

[0113] 2. The compressive strength test results of the alkali-activated concrete test blocks cured to different ages (3 days, 7 days, and 28 days) in the above embodiments using a press are shown in Table 1. It can be seen that the compressive strength of the alkali-activated concrete prepared in Examples 1 to 4 is significantly higher than that of Examples 5 to 6. This strength increase phenomenon is mainly due to the fact that the wastewater glass sand is strengthened and functionalized with calcium ions and tartaric acid, which promotes the formation of hydration products and produces a denser microstructure, thereby improving the compressive strength of the alkali-activated concrete, and the combined effect of the two is higher than that of the single treatment. In addition, the compressive strength of the alkali-activated concrete prepared in Examples 7 to 9 is relatively similar, indicating that the proposed technical solution is relatively stable in efficiency for modifying wastewater glass sand.

[0114] Table 1

[0115] 3-day compressive strength / MPa 7-day compressive strength / MPa 28-day compressive strength / MPa Example 1 28.7 31.9 39.6 Example 2 27.3 32.8 42.1 Example 3 23.7 27.5 37.5 Example 4 35.8 39.5 47.7 Example 5 16.4 20.1 23.6 Example 6 20.3 24.5 28.6 Example 7 29.5 35.4 37.5 Example 8 25.8 27.6 35.8 Example 9 29.8 29.3 37.5

[0116] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0117] The above shows and describes the basic principles, main features and advantages of the present disclosure. Those skilled in the art should understand that the present disclosure is not limited by the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present disclosure. Without departing from the spirit and scope of the present disclosure, the present disclosure may have various changes and improvements, and these changes and improvements fall within the scope of the present disclosure to be protected.

Claims

1. A method for preparing alkali-activated slag concrete using activated wastewater glass sand, It is characterized in that The steps include: (1) Mix cement and water in a mass ratio of 0.001:1 to 0.005:1, let stand for 2 to 24 hours, and take out the supernatant as the saturated cement solution; (2) Add tartaric acid to the saturated cement solution at a mass ratio of tartaric acid to saturated cement solution of 0.001:1 to 0.015:1, and heat the solution to 50 to 80°C; (3) Adding wastewater glass molding sand into the hot solution at a mass ratio of wastewater glass molding sand to hot solution of 0.1:1 to 0.5:1, stirring and then standing for 2 to 24 hours, filtering and drying, to obtain activated wastewater glass molding sand; (4) Alkali-activated slag concrete is prepared using activated wastewater glass sand, the components by weight being: 50-175 parts of activated wastewater glass sand, 120-460 parts of slag, 12-86 parts of fly ash, 75-265 parts of sand, 160-360 parts of gravel, 26-131 parts of alkaline activator, and 20-160 parts of water.

2. The method for preparing alkali-activated slag concrete by using activated wastewater glass sand according to claim 1, It is characterized in that In step (1), the cement is commercially available ordinary Portland cement, including at least one of strength grades 52.5, 42.5 and 32.

5.

3. The method for preparing alkali-activated slag concrete by using activated wastewater glass sand according to claim 1, It is characterized in that In step (2), the tartaric acid is at least one of industrial pure and analytical pure.

4. The method for preparing alkali-activated slag concrete by using activated wastewater glass sand according to claim 1, It is characterized in that In step (3), the waste water glass molding sand is a foundry molding sand prepared using water glass as a main binder, which is a waste powder after being used multiple times.

5. The method for preparing alkali-activated slag concrete by using activated wastewater glass sand according to claim 1, It is characterized in that In step (4), the alkaline activator is NaOH, water glass, Na 2 SO 4 、Na 2 CO 3 , MgO, lime, and KOH.

Images