Preparation method of solid waste-based mineral powder flat replacement material

Abstract

The invention discloses a preparation method of a solid-waste-based mineral powder flat replacement material, which comprises the following steps: respectively grinding 20-50 parts by weight of coal gangue, 15-25 parts by weight of waste glass and 12-25 parts by weight of slag, mixing, adding 1-5% of the total mass of raw materials, calcining in a high-temperature furnace at 1250-1490 DEG C for 2-5 hours, keeping the temperature for 60-120 minutes, performing water cooling treatment, and grinding until the specific surface area is 420-450m < 2 > / kg, thereby obtaining the solid-waste-based mineral powder flat replacement material. The sieve residue of the 45-micron square hole sieve is 1t; the 7d activity index of the solid waste-based mineral powder flat replacement material is larger than or equal to 75%, and the 28d activity index of the solid waste-based mineral powder flat replacement material is larger than or equal to 95%. The prepared flat replacement material can consume industrial solid wastes on a large scale, reduces pollution of the industrial solid wastes to the environment, saves land resources, improves the physicochemical properties of the industrial solid wastes, improves the error-tolerant rate of co-processing of various solid wastes, and has both economic benefits and environmental protection benefits.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of building materials, and particularly relates to a preparation method of a solid waste-based mineral powder flat-replacement material. BACKGROUND

[0002] With the continuous development of modern society, the long-term stacking of industrial solid wastes generated by steel enterprises, coal enterprises and thermal power plants in China not only occupies a large amount of land resources, but also seriously pollutes the environment. These industrial solid wastes are rich in useful elements such as silicon, aluminum and calcium, and idling stacking is actually a waste of resources. At the same time, the cost requirements for building materials in the process of infrastructure construction are also increasing, and it is also the future trend of infrastructure construction to reduce environmental pollution while ensuring the mechanical strength of cementitious materials. For example, most of the mineral powder is mixed into the cement as the key flat-replacement material of the cement in the process of using concrete and cement, and the mineral powder itself has certain hydration activity and is similar to the hydration activity of cement, which can reduce the material cost in the process of engineering construction.

[0003] The existing technology has significant defects in the preparation technology of mineral powder. For example, the invention patent application file (CN118771752A) discloses a kind of S95 mineral powder and its preparation method, and the raw materials only rely on vanadium-titanium ore slag and blast furnace slag, both of which have direct economic value for export, and are not the focus of industrial waste disposal. And it does not involve coal gangue, slag and other industrial wastes with large output and high disposal pressure, which cannot alleviate the industrial waste stacking dilemma of thermal power and coal mining enterprises, and has low environmental protection benefit.

[0004] If coal gangue, slag and other industrial wastes are used as the main raw material for preparing mineral powder flat-replacement material, and are modified into materials with hydration activity by special means, they can be directly used as cement mixed material to replace part of cementitious material in infrastructure construction, which can not only consume a large amount of industrial solid waste, but also reduce the pollution caused by industrial solid waste to the environment, save land resources, improve the fault tolerance of collaborative disposal of different solid wastes, and provide a diversified solid waste combination mode of resource utilization method. SUMMARY

[0005] The main purpose of the present application is to provide a preparation method of a solid waste-based mineral powder flat-replacement material, which aims to provide a resource utilization method for industrial solid waste and a mineral powder replacement field, combines the collaborative utilization of coal gangue, waste glass, slag and other industrial solid wastes, and uses processes such as step-by-step grinding, mixing calcination, temperature control and insulation, and cooling treatment to realize the efficient conversion of industrial solid wastes, and prepare mineral powder flat-replacement materials meeting performance requirements, which have environmental protection benefits and practical value.

[0006] To achieve the above purpose, a first aspect of the present application provides a preparation method of a solid waste-based mineral powder flat-replacement material

[0007] Specifically comprising the following steps:

[0008] The raw materials are respectively put into a grinder for pretreatment;

[0009] The pretreated materials are mixed and ground again to obtain raw materials;

[0010] The carbon powder is mixed with the raw materials and put into a crucible for calcination in a high-temperature furnace. After the calcination process, the high-temperature molten material is obtained after heat preservation.

[0011] The high-temperature molten material is then cooled to obtain an amorphous clinker;

[0012] The clinker is put into a grinder for grinding and sieving to remove impurities to obtain the solid waste-based mineral powder replacement material.

[0013] As a further preferred solution, the raw materials are one of coal gangue, waste glass, and slag or a mixture thereof;

[0014] The pretreatment includes preliminary grinding of the coal gangue, waste glass, and slag respectively to a specific surface area > 300 m 2 / kg, and screening to remove large particle impurities.

[0015] As a further preferred solution, the chemical composition of the waste glass contains < 3% Al2O3 and > 80% SiO2.

[0016] As a further preferred solution, the mixing ratio of the pretreated materials is 20-50 parts of coal gangue, 15-25 parts of waste glass, and 15-25 parts of slag by weight.

[0017] As a further preferred solution, the specific surface area of the raw material is > 380 m 2 / kg.

[0018] The addition amount of the carbon powder is 1-5% of the total mass of the raw material, which can ensure that the material is in a stable reducing atmosphere during the calcination process and avoid oxidation and deterioration of the material.

[0019] By precisely controlling the specific surface area of the material, the uniformity of the mixture of raw materials and the sufficiency of the subsequent high-temperature reaction are ensured, and the reactivity of the raw material is improved.

[0020] As a further preferred solution, the crucible is made of graphite material;

[0021] The use of a graphite crucible can avoid the adhesion of the material to the inner wall of the crucible during the high-temperature stage, reduce material loss, ensure the stability of the product composition, improve the use frequency of the material container, and reduce the use cost of the crucible. It has excellent high-temperature resistance,

[0022] The calcining in the high-temperature furnace specifically includes: a calcining temperature of 1250-1490 DEG C, and a calcining time of 2-5h.

[0023] The holding time after the calcining process is 60-120min.

[0024] As a further preferred solution, the cooling process specifically includes directly immersing the high-temperature molten material into cold water for rapid cooling;

[0025] The cold water has a temperature of 0-10 DEG C.

[0026] The high-temperature material can be modified through the low-temperature cold water treatment, the disposal range and utilization conditions of industrial solid waste can be widened, and the solid waste without hydration activity can be converted into a flat-replacement material that can be used to replace mineral powder.

[0027] Based on the second main aspect of the present application, the present application provides a solid waste-based mineral powder flat-replacement material prepared according to the above method.

[0028] As a further preferred solution, the specific surface area of the solid waste-based mineral powder flat-replacement material is 420-450m 2 / gram, and the sieve residue is <10% through a 45-micron square hole sieve.

[0029] By controlling the grinding time and the sieve size, the fineness of the obtained flat-replacement material particles can meet the use requirements of mineral powder replacement, and the adaptability of the material to cement and other substrates can be improved.

[0030] Based on the second main aspect of the present application, the present application provides a concrete admixture containing the solid waste-based mineral powder flat-replacement material.

[0031] Compared with the prior art, the present application first uses coal gangue, waste glass, waste ceramic tiles, tailings, waste and old refractory materials and many other solid wastes without hydration activity as raw materials, which are rich in types, widely sourced and easy to obtain, and provides an effective path for the collaborative resource utilization of multiple types of industrial solid waste.

[0032] Secondly, the present application further enhances the treatment effect of the raw materials through a step-by-step grinding process, and grinds multiple industrial solid wastes of different sources and different compositions to a specific surface area of >300m 2 / gram, and then grinds them to a specific surface area of >380m 2 / gram after mixing, which not only improves the uniformity of the material mixture, but also enables the components of various industrial solid wastes to fully contact and react during subsequent high-temperature treatment, effectively overcoming the product performance fluctuation problem caused by uneven mixing of multiple-component industrial solid wastes, and laying a structural foundation for the subsequent improvement of hydration activity.

[0033] Further, the present application realizes a breakthrough optimization of the properties of industrial solid waste by using a high-temperature calcination process. In a high-temperature environment, organic matter, impurities, and excess carbon and other substances that reduce the hydration reaction in industrial solid waste can be effectively removed, breaking the limitations of the original properties of solid waste, and enabling solid waste materials with complex chemical components to form clinker with uniform chemical components.

[0034] Finally, the present application has significant environmental benefits and practical value. On the one hand, it improves the resource utilization rate of multiple types of solid waste and reduces environmental pollution caused by the stacking of industrial solid waste. On the other hand, the prepared mineral powder replacement material can effectively replace mineral powder, and at the same time, the raw material cost is low, the process flow is clear, and it is suitable for industrial scale production, providing an environmentally friendly, efficient, and low-cost solution for the mineral powder replacement field, with good environmental and social benefits. BRIEF DESCRIPTION OF DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or prior art description. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to these drawings without creative labor.

[0036] Figure 1 A production flow chart of a solid waste-based mineral powder replacement material in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0037] The preferred embodiments of the present application will be described in detail below in order to more clearly understand the purposes, characteristics and advantages of the present application. It should be understood that the following embodiments are not a limitation on the scope of the present application, but only to illustrate the essential spirit of the technical solutions of the present application.

[0038] In the following description, certain specific details are set forth in order to provide a thorough understanding of various disclosed embodiments. However, persons of ordinary skill in the relevant arts will recognize that embodiments can be practiced without one or more of these specific details. In other instances, well-known techniques associated with the present application have not been described in detail or have been described only briefly to avoid unnecessarily obscuring the description of the embodiments.

[0039] Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics can be combined in any suitable manner in one or more embodiments.

[0040] As shown in FIG. 1, in one possible embodiment, a solid waste-based mineral powder flat-replacement material production flow chart specifically includes the following steps: Figure 1

[0041] Embodiment 1

[0042] (1) Raw material pretreatment

[0043] Coal gangue, waste glass, and slag are selected as core raw materials.

[0044] The coal gangue is removed of visible large particle impurities, and is put into a planetary ball mill, with a rotation speed set to 300 r / min, and a grinding time of 4 h. The specific surface area of the ground coal gangue is detected to be 325 m 2 / kg.

[0045] The waste glass with an Al2O3 content of 2.2% and a SiO2 content of 82.5% is crushed to a particle size of ≤10 mm, and is then put into a planetary ball mill, with a rotation speed set to 280 r / min, and a grinding time of 3.5 h. The specific surface area of the ground waste glass is detected to be 318 m 2 / kg.

[0046] The slag is removed of clumps, and is put into a planetary ball mill, with a rotation speed set to 320 r / min, and a grinding time of 4.5 h. The specific surface area of the ground slag is controlled to be 330 m 2 / kg.

[0047] (2) Raw material preparation

[0048] The raw materials obtained after pretreatment in the previous step are accurately measured: 35 parts of coal gangue, 20 parts of waste glass, and 20 parts of slag.

[0049] The three kinds of raw materials are put into a planetary ball mill for mixing and grinding, with a rotation speed set to 300 / min, and a grinding time of 3 h. The uniform raw material is obtained, with a specific surface area detected to be 395 m 2 / kg.

[0050] (3) Calcination and holding

[0051] 2.25 parts of industrial-grade carbon powder, accounting for 3% of the total mass of the raw material, is weighed, and is put into a mixer together with the above raw material for mixing for 20 min.

[0052] ​The mixture of raw material and carbon powder is loaded into a graphite crucible, and the filling height is two-thirds of the volume of the crucible to avoid overflow during high-temperature calcination.

[0053] The crucible is placed in a box-type high-temperature furnace, and the high-temperature furnace is started to heat from room temperature to 1350℃ at a rate of 10℃ / min, and calcined for 3h.

[0054] After the calcination process is completed, the material is kept for 90min to ensure that the material is fully reacted and the organic matter, impurities and excess carbon are removed, obtaining a high-temperature molten material.

[0055] (4) Cooling treatment

[0056] After the holding is completed, the graphite crucible containing the high-temperature molten material is quickly removed, and the high-temperature molten material is placed in cold water with a temperature of 0-10℃ for quenching treatment until the high-temperature molten material cools to room temperature, obtaining a clinker.

[0057] (5) Clinker post-treatment

[0058] The cooled clinker is put into a planetary ball mill, and the rotation speed is set to 350r / min, and the grinding time is 5h.

[0059] After grinding, the material is sieved by mechanical vibration for 15min using a 45μm square hole standard sieve, and the mass fraction of the residue is calculated to be 8.6%, the specific surface area of the clinker is detected to be 430m 2 / kg, the 7d activity index is 82.8%, and the 28d activity index is 97.7%, obtaining a solid waste-based mineral powder flat replacement material.

[0060] Example 2:

[0061] The difference between this example and Example 1 is that 20 parts of coal gangue, 15 parts of waste glass and 15 parts of slag are used to prepare a solid waste-based mineral powder flat replacement material at the lowest mixing ratio.

[0062] The preparation method is as follows:

[0063] (1) Raw material pretreatment

[0064] Coal gangue, waste glass and slag are selected as core raw materials.

[0065] The coal gangue is removed from the surface of the visible large particle impurities, and is put into a planetary ball mill, and the rotation speed is set to 300r / min, and the grinding time is 4h, and the specific surface area of the ground coal gangue is detected to be 325m 2 / kg.

[0066] The waste glass with Al2O3 content of 2.2% and SiO2 content of 82.5% is crushed to a particle size of ≤10 mm and then put into a planetary ball mill, the rotation speed is set to 280 r / min, and the grinding time is 3.5 h. The specific surface area of the ground waste glass is 318 m 2 / kg.

[0067] The slag is removed from the agglomeration and put into a planetary ball mill, the rotation speed is set to 320 r / min, and the grinding time is 4.5 h. The specific surface area of the ground slag is controlled to be 330 m 2 / kg.

[0068] (2) Raw material preparation

[0069] The raw materials obtained by pretreatment in the previous step are accurately measured: 20 parts of coal gangue, 15 parts of waste glass, and 15 parts of slag.

[0070] The three raw materials are put into a planetary ball mill for mixing and grinding, the rotation speed is set to 300 / min, and the grinding time is 3 h. The uniform raw material is obtained, and the specific surface area is 400 m 2 / kg.

[0071] (3) Calcination and holding

[0072] 1.5 parts of industrial-grade carbon powder accounting for 3% of the total mass of the raw material are weighed and put into the mixer together with the above-mentioned raw material for 20 min.

[0073] The mixture of raw material and carbon powder is loaded into a graphite crucible, and the filling height is two-thirds of the volume of the crucible to avoid overfilling and overflow during high-temperature calcination.

[0074] The crucible is placed in a box-type high-temperature furnace, and the high-temperature furnace is started. The temperature is raised to 1350℃ at a rate of 10℃ / min from room temperature, and calcination is carried out for 3 h.

[0075] After the calcination process is completed, holding is carried out for 90 min to ensure that the material is fully reacted and that organic matter, impurities, and excess carbon are removed, obtaining a high-temperature molten material.

[0076] (4) Cooling treatment

[0077] After the holding is completed, the graphite crucible containing the high-temperature molten material is quickly removed, and the high-temperature molten material is placed in cold water with a temperature of 0-10℃ for rapid cooling treatment until the high-temperature molten material cools to room temperature, obtaining a clinker.

[0078] (5) Clinker post-treatment

[0079] The cooled clinker is put into a planetary ball mill, and the rotation speed is set to 350 r / min, and the grinding time is 5 h.

[0080] After grinding, mechanical vibration screening is carried out for 15 min with a 45-μm square hole standard sieve, and the mass fraction of the oversize is 9.5% by calculation, and the specific surface area of the clinker is 450 m 2 / kg, the 7d activity index is 80.6%, the 28d activity index is 95.1%, and the solid waste-based mineral powder flat-replacement material is obtained.

[0081] Example 3

[0082] The difference between this example and Example 1 is that 50 parts of coal gangue, 25 parts of waste glass and 25 parts of slag are taken to prepare the solid waste-based mineral powder flat-replacement material at the highest mixing ratio.

[0083] The preparation method is as follows:

[0084] (1) Pretreatment of raw materials

[0085] Coal gangue, waste glass and slag are selected as core raw materials.

[0086] The coal gangue is removed from the surface of the visible large particle impurities, put into the planetary ball mill, the rotation speed is set to 300 r / min, and the grinding time is 4 h, and the specific surface area of the ground coal gangue is 325 m 2 / kg.

[0087] The waste glass with an Al2O3 content of 2.2% and a SiO2 content of 82.5% is crushed to a particle size of ≤10 mm and then put into the planetary ball mill, the rotation speed is set to 280 r / min, and the grinding time is 3.5 h, and the specific surface area of the ground waste glass is 318 m 2 / kg.

[0088] The slag is removed from the agglomeration and put into the planetary ball mill, the rotation speed is set to 320 r / min, and the grinding time is 4.5 h, and the specific surface area of the ground slag is controlled to be 330 m 2 / kg.

[0089] (2) Preparation of raw materials

[0090] Accurately measure the raw materials obtained by pretreatment in the previous step: 50 parts of coal gangue, 25 parts of waste glass and 25 parts of slag.

[0091] Put the three kinds of raw materials into the planetary ball mill for mixing and grinding, the rotation speed is set to 300 / min, and the grinding time is 3 h, to obtain uniform raw materials, and the specific surface area is 395 m 2 / kg.

[0092] (3) Calcination and heat preservation

[0093] Take 3 parts of industrial-grade carbon powder with a total mass of 3% of the raw materials, and put them into the mixer together with the above-mentioned raw materials for 20 min.

[0094] The mixture of raw material and carbon powder is loaded into a graphite crucible, and the filling height is two-thirds of the volume of the crucible to avoid overflow during high-temperature calcination.

[0095] The crucible is placed in a box-type high-temperature furnace, and the high-temperature furnace is started to heat up at a rate of 10℃ / min to 1350℃, and calcined for 3h.

[0096] After the calcination process is completed, the material is kept at temperature for 90min to ensure that the material is fully reacted and the organic matter, impurities and excess carbon are removed, obtaining a high-temperature molten material.

[0097] (4) Cooling treatment

[0098] After the holding is completed, the graphite crucible containing the high-temperature molten material is quickly removed, and the high-temperature molten material is placed in cold water with a temperature of 0-10℃ for rapid cooling treatment until the high-temperature molten material cools to room temperature, obtaining a clinker.

[0099] (5) Clinker post-treatment

[0100] The cooled clinker is put into a planetary ball mill, and the rotation speed is set to 350r / min, and the grinding time is 5h.

[0101] After grinding, the material is sieved by mechanical vibration for 15min using a 45μm square hole standard sieve, and the mass fraction of the residue is calculated to be 8.8%, the specific surface area of the clinker is detected to be 425m 2 / kg, the 7d activity index is 86%, and the 28d activity index is 100.1%, obtaining a solid waste-based mineral powder flat replacement material.

[0102] Example 4:

[0103] This example provides a solid waste-based mineral powder flat replacement material, which is different from the preparation method of Example 1 in that the slag in the raw material is replaced by waste ceramic tiles and the parameters of the calcination process are adjusted.

[0104] The preparation method is as follows:

[0105] (1) Raw material pretreatment:

[0106] Coal gangue, waste glass and waste ceramic tiles are selected as core raw materials.

[0107] The coal gangue is removed from the surface of the visible large particle impurities, and is put into a planetary ball mill, and the rotation speed is set to 300r / min, and the grinding time is 4h, and the specific surface area of the ground coal gangue is detected to be 325m 2 / kg.

[0108] The waste glass with Al2O3 content of 2.2% and SiO2 content of 82.5% is crushed to a particle size of ≤10 mm and then put into a planetary ball mill, the rotation speed is set to 280 r / min, and the grinding time is 3.5 h. The specific surface area of the ground waste glass is 318 m 2 / kg.

[0109] The waste ceramic tile is crushed, the surface glaze is removed by high-pressure water washing, and then dried and put into a planetary ball mill. The rotation speed is set to 330 r / min, and the grinding time is 5 h. The specific surface area of the ground waste ceramic tile is 322 m 2 / kg.

[0110] (2) Raw material preparation

[0111] Accurately measure the raw materials obtained by pretreatment in the previous step: coal gangue 35 parts, waste glass 20 parts, and waste ceramic tile 20 parts.

[0112] Put the three raw materials into a planetary ball mill for mixing and grinding, set the rotation speed to 300 / min, and the grinding time to 3 h to obtain a uniform raw material. The specific surface area is 388 m 2 / kg.

[0113] (3) Calcination and holding

[0114] Weigh 2.25 parts of industrial-grade carbon powder, which is 3% of the total mass of the raw material, and mix it with the above-mentioned raw material in a mixer for 20 minutes.

[0115] Put the mixture of raw material and carbon powder into a graphite crucible, fill it to two-thirds of the volume of the crucible to avoid overfilling and overflow during high-temperature calcination.

[0116] Put the crucible into a box-type high-temperature furnace, start the high-temperature furnace, and heat it from room temperature to 1380℃ at a rate of 10℃ / min, and calcine for 3.5 h.

[0117] After the calcination process is completed, hold for 100 min to ensure that the material is fully reacted and the organic matter, impurities and excess carbon are removed, obtaining a high-temperature molten material.

[0118] (4) Cooling treatment

[0119] After the holding is completed, quickly take out the graphite crucible containing the high-temperature molten material, and put the high-temperature molten material into cold water with a temperature of 0-10℃ for rapid cooling treatment until the high-temperature molten material cools to room temperature, obtaining a clinker.

[0120] (5) Clinker post-treatment

[0121] Put the cooled clinker into a planetary ball mill, set the rotation speed to 350 r / min, and grind for 5 h.

[0122] After grinding, mechanical vibration screening is carried out for 15 min with a 45-μm square hole standard sieve, and the mass fraction of the oversize is 8.9% by calculation, and the specific surface area of the clinker is 436 m 2 / kg, the 7d activity index is 80.8%, the 28d activity index is 95.3%, and a solid waste-based mineral powder flat replacement material is obtained.

[0123] Example 5:

[0124] The embodiment provides a solid waste-based mineral powder flat replacement material, and the difference from the preparation method in Example 1 is that the coal gangue in the raw material is replaced by tailings.

[0125] The preparation method is as follows:

[0126] (1) Pretreatment of raw materials

[0127] Tailings, waste glass and slag are selected as core raw materials.

[0128] The tailings are subjected to magnetic separation to remove magnetic impurities, and after drying, they are put into a planetary ball mill, the rotation speed is set to 300 r / min, and the grinding time is 5 h. The specific surface area of the ground coal gangue is 328 m 2 / kg.

[0129] The waste glass with an Al2O3 content of 2.2% and a SiO2 content of 82.5% is crushed to a particle size of ≤10 mm and then put into a planetary ball mill, the rotation speed is set to 280 r / min, and the grinding time is 3.5 h. The specific surface area of the ground waste glass is 318 m 2 / kg.

[0130] The slag is removed from the agglomeration and put into a planetary ball mill, the rotation speed is set to 320 r / min, and the grinding time is 4.5 h. The specific surface area of the ground slag is controlled to be 330 m 2 / kg.

[0131] (2) Preparation of raw materials

[0132] The raw materials obtained by pretreatment in the previous step are accurately measured: 35 parts of tailings, 20 parts of waste glass, and 20 parts of slag.

[0133] The three kinds of raw materials are put into a planetary ball mill for mixing and grinding, the rotation speed is set to 300 / min, and the grinding time is 3 h. The specific surface area of the obtained uniform raw material is 387 m 2 / kg.

[0134] (3) Calcination and heat preservation

[0135] 2.25 parts of industrial-grade carbon powder accounting for 3% of the total mass of the raw material are weighed and put into a mixer together with the above-mentioned raw material for 20 min.

[0136] The mixture of raw material and carbon powder is loaded into a graphite crucible, and the filling height is two-thirds of the volume of the crucible, avoiding overfilling and overflowing in high-temperature calcination.

[0137] The crucible is placed in a box-type high-temperature furnace, and the high-temperature furnace is started to heat up at a rate of 10℃ / min to 1380℃, and calcined for 3.5h.

[0138] After the calcination process is completed, the material is kept at temperature for 100min to ensure that the material is fully reacted and the organic matter, impurities and excess carbon are removed, obtaining a high-temperature molten material.

[0139] (4) Cooling treatment

[0140] After the holding is completed, the graphite crucible containing the high-temperature molten material is quickly removed, and the high-temperature molten material is placed in cold water with a temperature of 0-10℃ for quenching treatment until the high-temperature molten material cools to room temperature, obtaining a clinker.

[0141] (5) Clinker post-treatment

[0142] The cooled clinker is put into a planetary ball mill, and the rotation speed is set to 350r / min, and the grinding time is 5h.

[0143] After grinding, the material is mechanically vibrated and sieved for 15min using a 45μm square hole standard sieve, and the mass fraction of the retained material is calculated to be 8.6%, the specific surface area of the clinker is detected to be 438m 2 / kg, the 7d activity index is 80.6%, and the 28d activity index is 95.1%, obtaining a solid waste-based mineral powder flat replacement material.

[0144] Example 6:

[0145] The embodiment provides a solid waste-based mineral powder flat replacement material, and the difference from the preparation method of Example 1 is that the waste glass in the raw material is replaced by waste quartz refractory.

[0146] The preparation method is as follows:

[0147] (1) Raw material pretreatment

[0148] Coal gangue, waste quartz refractory and slag are selected as core raw materials.

[0149] The coal gangue is removed from the surface of the visible large particle impurities, and is put into a planetary ball mill, and the rotation speed is set to 300r / min, and the grinding time is 4h, and the specific surface area of the ground coal gangue is detected to be 325m 2 / kg.

[0150] The waste quartz refractory with Al2O3 content of 1.2% and SiO2 content of 86% is crushed to a particle size of ≤3 mm and then put into a planetary ball mill, the rotation speed is set to 290 r / min, and the grinding time is 5 h. The specific surface area of the ground waste glass is 320 m 2 / kg.

[0151] The slag is removed from the agglomeration and put into a planetary ball mill, the rotation speed is set to 320 r / min, and the grinding time is 4.5 h. The specific surface area of the ground slag is controlled to be 330 m 2 / kg.

[0152] (2) Raw material preparation

[0153] The raw materials obtained by pretreatment in the previous step are accurately measured: 35 parts of coal gangue, 20 parts of waste quartz refractory, and 20 parts of slag.

[0154] The three raw materials are put into a planetary ball mill for mixing and grinding, the rotation speed is set to 300 / min, and the grinding time is 3.5 h. The uniform raw material is obtained, and the specific surface area is 389 m 2 / kg.

[0155] (3) Calcination and holding

[0156] 2.25 parts of industrial-grade carbon powder accounting for 3% of the total mass of the raw material are weighed and put into a mixer together with the above-mentioned raw material for 20 min.

[0157] The mixture of raw material and carbon powder is loaded into a graphite crucible, and the filling height is two-thirds of the volume of the crucible to avoid overfilling and overflow during high-temperature calcination.

[0158] The crucible is placed in a box-type high-temperature furnace, and the high-temperature furnace is started. The temperature is raised to 1390℃ at a rate of 10℃ / min from room temperature, and calcination is carried out for 3.5 h.

[0159] After the calcination process is completed, the holding time is 100 min to ensure that the material is fully reacted and the organic matter, impurities, and excess carbon are removed, obtaining a high-temperature molten material.

[0160] (4) Cooling treatment

[0161] After the holding is completed, the graphite crucible containing the high-temperature molten material is quickly removed, and the high-temperature molten material is placed in cold water with a temperature of 0-10℃ for rapid cooling treatment until the high-temperature molten material cools to room temperature, obtaining a clinker.

[0162] (5) Clinker post-treatment

[0163] The cooled clinker is put into a planetary ball mill, and the rotation speed is set to 350 r / min, and the grinding time is 5 h.

[0164] After grinding, mechanical vibration screening is carried out for 15 min with a 45-μm square hole standard sieve, and the mass fraction of the oversize is 8.6% by calculation, and the specific surface area of the clinker is 441 m 2 / kg, the 7d activity index is 84.4%, the 28d activity index is 99.5%, and the solid waste-based mineral powder flat-replacement material is obtained.

[0165] Example 7:

[0166] The embodiment provides a solid waste-based mineral powder flat-replacement material, and different from the preparation method in Example 1 is that: the coal gangue, waste glass and slag in the raw materials are replaced by tailings, waste quartz refractory and waste ceramic tiles.

[0167] The preparation method is as follows:

[0168] (1) Raw material pretreatment

[0169] Tailings, waste quartz refractory and waste ceramic tiles are selected as core raw materials.

[0170] The tailings are subjected to magnetic separation to remove magnetic impurities, and after drying, they are put into a planetary ball mill, the rotation speed is set to 300 r / min, and the grinding time is 5 h, and the specific surface area of the coal gangue after grinding is 328 m 2 / kg.

[0171] The waste quartz refractory with an Al2O3 content of 1.2% and a SiO2 content of 86% is crushed to a particle size of ≤3 mm and then put into a planetary ball mill, the rotation speed is set to 290 r / min, and the grinding time is 5 h, and the specific surface area of the waste glass after grinding is 320 m 2 / kg.

[0172] The waste ceramic tile is crushed, the surface glaze is removed by high-pressure water washing, and after drying, it is put into a planetary ball mill, the rotation speed is set to 330 r / min, and the grinding time is 5 h, and the specific surface area of the waste ceramic tile after grinding is 322 m 2 / kg.

[0173] (2) Raw material preparation

[0174] The raw materials obtained by pretreatment in the above step are accurately measured: 35 parts of tailings, 20 parts of waste quartz refractory, and 20 parts of waste ceramic tile.

[0175] The three kinds of raw materials are put into a planetary ball mill for mixing and grinding, the rotation speed is set to 300 / min, and the grinding time is 3.5 h, to obtain a uniform raw material, and the specific surface area is 398 m 2 / kg.

[0176] (3) Calcination and heat preservation

[0177] Take 3% of the total mass of raw materials, 2.25 parts of industrial-grade carbon powder, and mix them with the above raw materials in a mixer for 20 minutes.

[0178] The mixture of raw materials and carbon powder is loaded into a graphite crucible with a filling height of two-thirds of the volume of the crucible to avoid overfilling and overflow during high-temperature calcination.

[0179] The crucible is placed in a box-type high-temperature furnace, and the high-temperature furnace is started to heat from room temperature to 1400℃ at a rate of 10℃ / min, and calcined for 4h.

[0180] After the calcination process, the material is kept at temperature for 110 minutes to ensure that the material is fully reacted and the organic matter, impurities and excess carbon are removed, obtaining high-temperature molten material.

[0181] (4) Cooling treatment

[0182] After the temperature holding is completed, the graphite crucible containing the high-temperature molten material is quickly removed and the high-temperature molten material is placed in cold water with a temperature of 0-10℃ for rapid cooling treatment until the high-temperature molten material cools to room temperature, obtaining clinker.

[0183] (5) Clinker post-treatment

[0184] The cooled clinker is placed in a planetary ball mill with a rotation speed of 350r / min and ground for 5h.

[0185] After grinding, the material is sieved mechanically with a 45μm square hole standard sieve for 15 minutes, and the mass fraction of the residue is calculated to be 8.4%, the specific surface area of the clinker is detected to be 437m 2 / kg, the 7d activity index is 81.2%, and the 28d activity index is 95.8%, obtaining solid waste-based mineral powder replacement material.

[0186] According to the above examples, the 7d activity index of the solid waste-based mineral powder replacement material prepared in each group of examples is ≥75%, and the 28d activity index is ≥95%.

[0187] Therefore, the present application uses high-temperature treatment to form a molten state of all materials, and then directly pours the molten material into cold water to form an amorphous clinker, so that a variety of solid waste materials without hydration activity can finally form an amorphous clinker with hydration activity, which can be used to replace mineral powder.

[0188] The application can convert many solid wastes (including but not limited to coal gangue, waste glass, waste ceramic tile, tailings, waste and old refractory materials and the like) without hydration activity into alternative materials with hydration activity, and the raw material source of the mineral powder replacement material is wide, has small limitation and is easy to obtain. The organic matter, impurities, carbon and the like in the solid waste can be reduced through high-temperature treatment to reduce the substances reducing the hydration reaction, break the limitation of the original properties of the solid waste, and make the solid waste materials with complex chemical components form clinker with uniform chemical components.

[0189] The technical terms, technical principles or technical means related to the technical solutions of the application involved in the above embodiments, which are not described in detail in the above content, are all known technologies or common means mastered by those skilled in the art.

[0190] The basic principles and main features of the application and the advantages of the application are shown and described above. It should be understood by those skilled in the art that the application is not limited by the above embodiments, and the above embodiments and the description in the specification are only to illustrate the principles of the application. Without departing from the spirit and scope of the application, various changes and improvements can be made to the application, and these changes and improvements all fall within the scope of the application. The scope of protection of the application is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a solid waste-based mineral powder substitute material, characterized in that, Includes the following steps: The raw materials are placed into a grinding mill for pretreatment. The pretreated materials are mixed and ground again to obtain raw material; Carbon powder is mixed with the raw material and placed in a crucible. The mixture is then calcined in a high-temperature furnace. After the calcination process is completed, the mixture is kept at a constant temperature to obtain a high-temperature molten material. The high-temperature molten material is then cooled to obtain amorphous clinker; The clinker is ground in a grinder and then sieved to remove impurities, thus obtaining the solid waste-based mineral powder substitute material.

2. The method for preparing solid waste-based mineral powder substitute materials according to claim 1, characterized in that, The raw materials are one or a mixture of coal gangue, waste glass, and slag; The pretreatment includes preliminary grinding of the coal gangue, waste glass, and slag until the specific surface area is >300m². 2 / kg, and screened to remove large particulate impurities.

3. The method for preparing solid waste-based mineral powder substitute materials according to claim 2, characterized in that, The waste glass has a chemical composition of <3% Al2O3 and >80% SiO2.

4. The method for preparing solid waste-based mineral powder substitute materials according to claim 1 or 2, characterized in that, The mixing ratio of the pretreated materials is as follows, by weight: 20-50 parts coal gangue, 15-25 parts waste glass, and 15-25 parts slag.

5. The method for preparing solid waste-based mineral powder substitute materials according to claim 1, characterized in that, The specific surface area of ​​the raw material is >380m². 2 / kg; The amount of carbon powder added is 1 to 5% of the total mass of the raw material.

6. The method for preparing solid waste-based mineral powder substitute materials according to claim 1, characterized in that, The crucible is made of graphite. The calcination in the high-temperature furnace specifically includes: a calcination temperature of 1250~1490℃ and a calcination time of 2-5h; and a heat preservation time of 60-120min after the calcination process.

7. The method for preparing solid waste-based mineral powder substitute materials according to claim 1, characterized in that, The cooling process specifically includes immersing the high-temperature molten material directly into cold water for rapid cooling. The temperature of the cold water is 0~10℃.

8. A solid waste-based mineral powder substitute material, characterized in that, Prepared by the method according to any one of claims 1-7.

9. The solid waste-based mineral powder substitute material according to claim 8, characterized in that, Specific surface area is 420-450 m² 2 / kg, and the residue after sieving through a 45μm square hole sieve is <10%.

10. A concrete admixture, characterized in that, The solid waste-based mineral powder substitute material as described in any one of claims 8-9.

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