All-solid-waste high-activity composite admixture and preparation method thereof

Abstract

The invention relates to an all-solid-waste high-activity composite admixture and a preparation method thereof. The all-solid-waste high-activity composite admixture is prepared from the following raw materials: mixed grinding micro powder of steel slag tailings and refining slag, and slag micro powder, wherein in parts by weight, the content of the mixed grinding micro powder is 20 to 30 parts, and the content of the slag micro powder is 70 to 80 parts. Through the synergistic effect of raw material co-doping, the activity of the admixture is improved, and the stability of chemical performance indexes of the admixture is ensured; the use ratio of the admixture in cement and mortar is increased, the consumption of cement is reduced, and the cost is further reduced. According to the invention, resource utilization of metallurgical industry solid wastes such as steel slag tailings, refining slag and blast furnace slag is realized, and the problem that the metallurgical industry solid wastes cannot be consumed due to long-term stockpiling is solved.

Description

Technical Field

[0001] The present application relates to the technical field of solid waste resource utilization and composite admixtures, and in particular to a full-solid waste high-activity composite admixture and a preparation method thereof. Background Art

[0002] Steel companies are paying more and more attention to the resource utilization of industrial solid waste. Iron and steel metallurgical slag solid waste mainly includes blast furnace slag, converter slag and refined slag, etc., with large output and low utilization rate, and most of them are in a long-term storage state.

[0003] At present, blast furnace slag is widely used in building materials such as cement, mortar and concrete. Due to the implementation of large-scale pelletizing in blast furnaces in recent years, the output of blast furnace slag has decreased year by year, the quality of slag is uneven, and high-quality slag is in short supply. Converter slag is a by-product produced in the steelmaking process. After the slag is crushed and iron is selected, the slag tailings are obtained. There are potential stability problems. It is difficult to directly use it as an aggregate in the building materials industry and it is difficult to consume and treat it on a large scale. Refined slag is a by-product produced in the refining process of molten steel. With the improvement of the quality requirements of molten steel, the output of refined slag has increased. Simple storage is prone to cause soil and water pollution. Summary of the invention

[0004] The present application provides a fully solid waste high-activity composite admixture and a preparation method thereof to solve the following technical problem: how to improve the effective utilization rate of iron and steel metallurgical slag solid waste.

[0005] In a first aspect, the present application provides a high-activity composite admixture made of all-solid waste, wherein the raw materials of the high-activity composite admixture made of all-solid waste include:

[0006] Mixed powder of steel slag tailings and refined slag, and slag powder; wherein, by weight,

[0007] The content of the mixed-grinding fine powder is 20 parts to 30 parts, and the content of the slag fine powder is 70 parts to 80 parts.

[0008] Optionally, it is characterized in that, relative to 100 parts by weight of the mixed-grinded micropowder, the steel slag tailings are 80 parts to 90 parts, and the refined slag is 10 parts to 20 parts.

[0009] Optionally, the steel slag tailings meet the following characteristics: MFe content is not greater than 1% by weight, binary basicity is not less than 3, and particle size is less than 5 mm.

[0010] Optionally, the mixed-grinding micropowder meets the following characteristics: specific surface area 400m 2 / kg~500m 2 / kg, 28d activity index is not less than 80%, moisture content is less than 1%.

[0011] Optionally, the chemical components of the mixed-grinding micropowder include:

[0012] CaO, SiO2, Al2O3, MgO, SO3 and Cl; among them, in terms of mass fraction,

[0013] The content of CaO is 30% to 50%, the content of SiO2 is 10% to 25%, the content of Al2O3 is 5% to 10%, the content of MgO is 5% to 8%, the content of SO3 is 0 to 3%, and the content of Cl is 0 to 0.06%.

[0014] Optionally, the slag powder meets the following characteristics: specific surface area 380m 2 / kg~450m 2 / kg, 28d activity index is not less than 95%, moisture content is less than 1%.

[0015] Optionally, the chemical components of the slag powder include:

[0016] CaO, SiO2, Al2O3, MgO, SO3 and Cl; among them, in terms of mass fraction,

[0017] The content of CaO is 30% to 50%, the content of SiO2 is 20% to 35%, the content of Al2O3 is 10% to 20%, the content of MgO is 8% to 12%, the content of SO3 is 0 to 3%, and the content of Cl is 0 to 0.06%.

[0018] In a second aspect, the present application provides a method for preparing the all-solid waste high-activity composite admixture described in the first aspect, the method comprising:

[0019] The steel slag tailings are premixed with the refined slag and then ground to obtain homogenized mixed-ground micro powder;

[0020] Mixing the homogenized mixed-grinding micropowder with slag micropowder to obtain a mixture;

[0021] The mixed material is subjected to secondary homogenization treatment to obtain a fully solid waste high-activity composite admixture.

[0022] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0023] The all-solid waste high-activity composite admixture provided in the embodiment of the present application has a refined slag with good grindability, and the refined slag is mixed with steel slag tailings to obtain a mixed ground powder, the mixed ground powder has a good particle size distribution, and the refined slag powder has a smaller particle size and specific surface area; the refined slag powder can shorten the coagulation time of slag powder and steel slag tailings powder, and improve the early activity index; the slag powder serves as the main raw material to provide high compressive strength for the all-solid waste high-activity composite admixture, and the mixed ground powder serves as an auxiliary raw material, the steel slag tailings powder and the refined slag powder with calcium oxide can provide an alkaline environment, promote the dissociation of amorphous slag powder, and improve the hydration process of the slag powder, thereby improving the activity of the composite admixture. In summary, the highly active all-solid waste high-activity composite admixture increases the proportion of admixtures used in concrete and mortar, saves cement consumption, and realizes the resource utilization of metallurgical industrial solid waste such as steel slag tailings, refined slag and blast furnace slag, solving the problem of their long-term storage and occupation of land and inability to be digested. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0025] In order to more clearly illustrate the embodiments of the present application 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, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0026] Figure 1 A schematic diagram of a process for preparing a high-activity composite admixture made of all-solid waste according to some embodiments of the present application;

[0027] Figure 2 The present invention is a schematic diagram of a detailed process of a method for preparing a highly active composite admixture made of all-solid waste according to some embodiments of the present application. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0029] Various embodiments of the present application may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be understood as a rigid limitation on the scope of the present application; therefore, the range description should be considered to have specifically disclosed all possible sub-ranges and single numerical values ​​within the range. For example, the range description from 1 to 6 should be considered to have specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which apply regardless of the range. In addition, whenever a numerical range is indicated herein, it is meant to include any cited number (fractional or integer) within the indicated range.

[0030] In this application, the terms "including", "comprising", etc. mean "including but not limited to".

[0031] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in this application can be purchased from the market or prepared by existing methods.

[0032] In a first aspect, the present application provides a high-activity composite admixture made of all-solid waste, wherein the raw materials of the high-activity composite admixture made of all-solid waste include:

[0033] Mixed powder of steel slag tailings and refined slag, and slag powder; wherein, by weight,

[0034] The content of the mixed-grinding fine powder is 20 parts to 30 parts, and the content of the slag fine powder is 70 parts to 80 parts.

[0035] In the embodiment of the present application, the refined slag has good easy-to-grind properties, and the refined slag is mixed and ground with steel slag tailings to obtain mixed ground micropowder, which has a good particle size distribution, and the refined slag micropowder has a smaller particle size and specific surface area; the refined slag micropowder can shorten the coagulation time of slag micropowder and steel slag tailings micropowder, and improve the early activity index; slag micropowder as the main raw material provides high compressive strength for the all-solid waste high-activity composite admixture, and mixed ground micropowder as an auxiliary raw material, steel slag tailings micropowder and refined slag micropowder with calcium oxide can provide an alkaline environment, promote the dissociation of amorphous slag micropowder, and improve the hydration process of slag micropowder, thereby improving the activity of the composite admixture. Reasonably regulate the content of slag micropowder and mixed ground micropowder so that the all-solid waste high-activity composite admixture has a higher compressive strength. Exemplarily, the content of mixed ground micropowder can be 20 parts, 21 parts, 22 parts, 23 parts, 24 parts, 25 parts, 26 parts, 27 parts, 28 parts, 29 parts, etc.; the content of slag micropowder can be 70 parts, 71 parts, 72 parts, 73 parts, 74 parts, 75 parts, 76 parts, 77 parts, 78 parts, 79 parts, 80 parts, etc.

[0036] In some embodiments, it is characterized in that, relative to 100 parts by weight of the mixed-milled fine powder, the steel slag tailings are 80 parts to 90 parts, and the refined slag is 10 parts to 20 parts.

[0037] In the embodiment of the present application, the steel slag tailings are different from the components of the finishing rolling. The steel slag contains a high amount of dicalcium silicate and tricalcium silicate active substances; the refined slag contains a high aluminum content and has an early setting component. Excessive refined slag will reduce the compressive strength of the mixed and ground micro powder. The steel slag tailings powder can ensure sufficient hydration products, and an appropriate amount of refined slag can play an alkali excitation role and shorten the setting time. Exemplarily, the above-mentioned steel slag tailings can be 80 parts, 81 parts, 82 parts, 83 parts, 84 parts, 85 parts, 86 parts, 87 parts, 88 parts, 89 parts, 90 parts, etc., and the above-mentioned refined slag can be 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts, 19 parts, 20 parts, etc.

[0038] In some embodiments, the steel slag tailings meet the following characteristics: MFe content is not greater than 1% by weight, binary basicity is not less than 3, and particle size is less than 5 mm.

[0039] In the embodiment of the present application, the steel slag tailings are obtained by mechanical crushing and magnetic separation of cooled converter steel slag. The MFe content is limited to ensure the grindability of the steel slag and avoid increasing the grinding cost and damaging the grinding equipment; the binary alkali is limited so that the steel slag tailings can better stimulate the slag powder, thereby improving the activity index of the composite admixture; the steel slag tailings have a suitable particle size when entering the mill to avoid the increase of subsequent grinding work and the increase of cost. Exemplarily, in the above-mentioned steel slag tailings, the MFe content can be 1% by weight, 0.9% by weight, 0.8% by weight, 0.7% by weight, etc., the binary basicity can be 3.0, 3.2, 3.4, 3.6, 3.8, 4.0, etc., and the particle size can be 4mm, 3mm, 2mm, etc.

[0040] In some embodiments, the mixed milled powder meets the following characteristics: specific surface area 400m 2 / kg~500m 2 / kg, 28d activity index is not less than 80%, moisture content is less than 1%.

[0041] In some embodiments, the chemical components of the mixed milled powder include:

[0042] CaO, SiO2, Al2O3, MgO, SO3 and Cl; among them, in terms of mass fraction,

[0043] The content of CaO is 30% to 50%, the content of SiO2 is 10% to 25%, the content of Al2O3 is 5% to 10%, the content of MgO is 5% to 8%, the content of SO3 is 0 to 3%, and the content of Cl is 0 to 0.06%.

[0044] In the embodiment of the present application, the mixed and ground micro-powder having the above characteristics can make the mixed and ground micro-powder meet the activity index requirements. For example, the specific surface area of ​​the mixed and ground micro-powder can be 400m 2 / kg, 420m 2 / kg, 440m 2 / kg, 460m 2 / kg, 480m 2 / kg、500m 2 / kg, etc., the 28d activity index can be 80%, 81%, 82%, 83%, etc., and the moisture content can be 0.9%, 0.8%, 0.7%, etc. In the chemical composition of the above-mentioned mixed milled powder, the content of CaO can be 30%, 35%, 40%, 45%, 50%, etc., the content of SiO2 can be 10%, 15%, 20%, 25%, etc., the content of Al2O3 can be 5%, 7%, 9%, 10%, etc., the content of MgO can be 5%, 6%, 7%, 8%, etc., the content of SO3 can be 1%, 2%, 3%, etc., and the content of Cl can be 0.03%, 0.04%, 0.05%, 0.06%, etc.

[0045] In some embodiments, the slag powder meets the following characteristics: specific surface area 380m 2 / kg~450m 2 / kg, 28d activity index is not less than 95%, moisture content is less than 1%.

[0046] In some embodiments, the chemical components of the slag powder include:

[0047] CaO, SiO2, Al2O3, MgO, SO3 and Cl; among them, in terms of mass fraction,

[0048] The content of CaO is 30% to 50%, the content of SiO2 is 20% to 35%, the content of Al2O3 is 10% to 20%, the content of MgO is 8% to 12%, the content of SO3 is 0 to 3%, and the content of Cl is 0 to 0.06%.

[0049] In the embodiment of the present application, the slag powder having the above characteristics can make the slag powder meet the activity index requirements. For example, the specific surface area of ​​the slag powder can be 380m 2 / kg, 390m 2 / kg、400m 2 / kg, 410m2 / kg, 420m 2 / kg, 430m 2 / kg, 440m 2 / kg, 450m 2 / kg, etc., the 28d activity index can be 95%, 96%, 97%, etc., and the moisture content can be 0.9%, 0.8%, 0.7%, etc. In the chemical composition of the slag powder, the CaO content can be 30%, 35%, 40%, 45%, 50%, etc., the SiO2 content is 20%, 25%, 30%, 35%, the Al2O3 content is 10%, 15%, 20%, etc., the MgO content is 8%, 10%, 12%, etc., the SO3 content is 1%, 2%, 3%, etc., and the Cl content is 0.03%, 0.04%, 0.05%, 0.06%, etc.

[0050] In a second aspect, the present application provides a method for preparing the all-solid waste high-activity composite admixture described in the first aspect, Figure 1 This is a schematic diagram of a process for preparing a high-activity composite admixture of all-solid waste according to some embodiments of the present application; see Figure 1 , the method comprising:

[0051] S1, premixing steel slag tailings and refined slag, and then grinding them to obtain homogenized mixed-grinding micro powder;

[0052] In the embodiment of the present application, the mixed ground micro-powder is prepared by mechanically crushing and magnetically separating the cooled converter slag, and the remaining waste slag is further crushed into steel slag tailings with a particle size of less than 5 mm. The steel slag tailings and refined slag are mixed and put into a vertical mill. After grinding, drying and powder selection, they are prepared into micro-powder, and the mixed ground micro-powder is obtained after meeting the index requirements.

[0053] S2, mixing the homogenized mixed powder with the slag powder to obtain a mixture;

[0054] In the embodiment of the present application, blast furnace slag is ground, dried, and selected to prepare fine powder, and slag fine powder is obtained after meeting the index requirements. The mixed ground fine powder and slag fine powder are mixed and put into a double-screw auger mixer for stirring, mixing and homogenizing to obtain a mixture.

[0055] S3, subjecting the mixture to secondary homogenization treatment to obtain a fully solid waste high-activity composite admixture.

[0056] In the embodiments of the present application, the mixture has a secondary homogenization effect during the process of entering and exiting the warehouse, thereby achieving a high degree of homogenization of the composite admixture. Figure 2 For a detailed schematic diagram of a method for preparing a high-activity composite admixture of all-solid waste according to some embodiments of the present application, please refer to Figure 2 .

[0057] The preparation method of the all-solid waste high-activity composite admixture is realized based on the above-mentioned all-solid waste high-activity composite admixture. The specific raw material components of the all-solid waste high-activity composite admixture can refer to the above-mentioned embodiment. Since the preparation method of the all-solid waste high-activity composite admixture adopts part or all of the technical solutions of the above-mentioned embodiments, it has at least all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be repeated here one by one.

[0058] The all-solid waste high-activity composite admixture and the preparation method thereof provided in the embodiments of the present application have at least the following technical effects:

[0059] (1) The use of all-solid waste high-activity composite admixtures provides a way to recycle industrial solid wastes such as blast furnace slag, steel slag tailings, and refined slag, solving the problem of long-term storage and inability to dispose of metallurgical slag;

[0060] (2) By adding steel slag tailings, the synergistic effect of blast furnace slag and steel slag tailings can be achieved, the comprehensive properties of the admixture such as fluidity and activity can be improved, and the current problems of insufficient slag supply and poor quality can be solved. At the same time, the price of steel slag tailings is low, which has cost advantages;

[0061] (3) By adding refined slag, on the one hand, the setting time can be shortened, solving the problem of long setting time of slag powder and steel slag powder; on the other hand, the hydration activity of slag powder and steel slag powder can be increased through alkali excitation, further improving the performance of the admixture;

[0062] (4) By adopting a two-stage double mixing measure, steel slag tailings and refined slag are mixed before grinding and homogenized in grinding, and the ground mixed powder and slag powder are mixed after grinding and homogenized in the mixer and storage, the admixture is fully homogenized and the performance of the admixture is guaranteed to be stable.

[0063] (5) The proportion of admixtures added is increased, which saves the use of cement, reduces costs and carbon dioxide emissions. In addition, the use of admixtures together with cement can effectively prevent the leaching of potential harmful substances in industrial solid waste and its impact on the environment through the sealing effect of cement.

[0064] The present application will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are intended only to illustrate the present application and are not intended to limit the scope of the present application. The experimental methods for which specific conditions are not specified in the following examples are usually measured according to national standards. If there is no corresponding national standard, then the conditions recommended by the manufacturer are followed.

[0065] Example 1

[0066] A fully solid waste high-activity composite admixture comprises the following components in parts by weight: 20 parts of mixed-grinding micropowder and 80 parts of slag micropowder.

[0067] The mixed-grinding micro-powder comprises 90 parts by weight of steel slag tailings and 10 parts of refined slag, which are prepared by mixed grinding.

[0068] The steel slag tailings are obtained by mechanically crushing and magnetically separating the cooled converter steel slag. The steel slag tailings have an MFe content of 0.9%, a binary basicity of 3.6, and a particle size of less than 5 mm.

[0069] The specific surface area of ​​the mixed powder is 450m 2 / kg, moisture 0.9%, the mass percentage of the main components is CaO45.83%, SiO2 13.31%, Al2O38.42%, MgO 6.14%, SO3 0.36%, Cl 0.03%.

[0070] The specific surface area of ​​slag powder is 420m 2 / kg, moisture 0.8%, the mass percentage of the main components is CaO42.25%, SiO2 33.61%, Al2O3 15.13%, MgO 8.02%, SO3 2.05%, Cl 0.05%.

[0071] A method for preparing a fully solid waste high-activity composite admixture, comprising:

[0072] After the cooled converter slag is mechanically crushed and magnetically separated for iron, the remaining waste slag is further crushed into steel slag tailings with a particle size of less than 5mm. The steel slag tailings and refined slag are metered and proportioned according to weight, and put into the vertical mill equipment. After grinding, drying and powder selection, micro powder is prepared. After meeting the index requirements, mixed milled micro powder is obtained;

[0073] Blast furnace slag is ground, dried and selected to produce fine powder, and slag fine powder is obtained after meeting the index requirements;

[0074] The mixed-grinding micro-powder and the slag micro-powder are measured and proportioned according to weight proportions, and are put into a double-screw auger mixer for stirring, mixing and homogenization to obtain a high-activity composite admixture of all-solid waste.

[0075] Example 2

[0076] Comparing Example 2 with Example 1, the difference between Example 2 and Example 1 is:

[0077] The specific surface area of ​​the mixed powder is 400m 2 / kg.

[0078] The specific surface area of ​​slag powder is 380m 2 / kg.

[0079] Example 3

[0080] Comparing Example 3 with Example 1, the difference between Example 3 and Example 1 is:

[0081] The specific surface area of ​​the mixed powder is 500m 2 / kg.

[0082] The specific surface area of ​​slag powder is 450m 2 / kg.

[0083] Example 4

[0084] Comparing Example 4 with Example 1, the difference between Example 4 and Example 1 is:

[0085] 30 parts of mixed grinding powder and 70 parts of slag powder.

[0086] The mixed-grinding micro powder includes 90 parts of steel slag tailings and 10 parts of refined slag.

[0087] Example 5

[0088] Comparing Example 5 with Example 1, the difference between Example 5 and Example 1 is:

[0089] 20 parts of mixed grinding powder and 80 parts of slag powder.

[0090] The mixed-grinding micro powder includes 80 parts of steel slag tailings and 20 parts of refined slag.

[0091] Example 6

[0092] Comparing Example 6 with Example 1, the difference between Example 6 and Example 1 is:

[0093] 25 parts of mixed grinding powder and 75 parts of slag powder.

[0094] The mixed-grinding micro powder includes 85 parts of steel slag tailings and 15 parts of refined slag.

[0095] The specific surface area of ​​the mixed powder is 450m 2 / kg.

[0096] The specific surface area of ​​slag powder is 420m 2 / kg.

[0097] Comparative Example 1

[0098] Comparing Comparative Example 1 with Example 1, the difference between Comparative Example 1 and Example 1 is:

[0099] 100 parts of slag powder were used alone as an admixture.

[0100] Comparative Example 2

[0101] Comparing Comparative Example 2 with Example 1, the difference between Comparative Example 2 and Example 1 is:

[0102] 80 parts of slag powder, 20 parts of steel slag tailings powder, and no refined slag powder is added to the composite admixture.

[0103] Comparative Example 3

[0104] Comparing Comparative Example 3 with Example 1, the difference between Comparative Example 4 and Example 1 is:

[0105] 75 parts of steel slag tailings and 25 parts of refined slag.

[0106] According to the testing requirements specified in GB / T 28293-2012 "Steel Slag Powder" standard, the performance of the admixtures in the above embodiments was tested with a ratio of cement to composite admixture of 1:1. The test results of activity index, setting time, etc. are shown in Table 1.

[0107] Table 1 Composite admixture performance test results

[0108]

[0109] Activity index refers to the ratio of the compressive strength of mortar specimens prepared with 50% composite admixture and 50% standard cement to that of mortar specimens prepared with standard cement and cured to the same specified age under standard conditions. The setting time (min) and stability tests are carried out in accordance with the national standard GBT1346-2011 "Test Methods for Water Consumption, Setting Time and Stability of Cement Standard Consistency".

[0110] It can be seen from the test result table 1 that the 7d activity index of the all-solid waste high-activity composite admixture provided by the embodiment of the present application is greater than 75%, and the 28-day activity index is greater than 90%. By comparing the results of Example 1, Example 2 and Example 3, it can be seen that with the increase of specific surface area, the activity of the composite admixture is improved, and the setting time is also shortened; by comparing the results of Example 1, Example 4 and Example 6, it can be seen that with the increase of the mixing and grinding micro-powder incorporation ratio, the 7d and 28d activity indexes gradually increase; by comparing the results of Example 1, Example 5 and Example 6, it can be seen that the proportion of refined slag in the mixed micro-powder is increased, so that the activity index of admixture 7 is increased, and the initial setting and final setting times are shortened; and the test results of Comparative Example 1 show that the activity index is slightly lower without the addition of refined slag and steel slag tailings; and the test results of Comparative Example 2 show that the activity index is low without the addition of refined slag, and the setting time increases; and it can be seen from Comparative Example 3 that when too much refined slag is added, the setting time of the admixture will be too short.

[0111] Therefore, the all-solid waste high-activity composite admixture provided in the embodiment of the present application provides a way to resource utilization of metallurgical industrial solid wastes such as blast furnace slag, steel slag tailings, and refined slag. It not only reduces costs, saves cement usage and reduces carbon emissions, but also has stable performance and can meet the performance index requirements of admixtures.

[0112] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A high-activity composite admixture made of solid waste, characterized in that: The raw materials of the all-solid waste high-activity composite admixture include: Mixed powder of steel slag tailings and refined slag, and slag powder; wherein, by weight, The content of the mixed-grinding fine powder is 20 parts to 30 parts, and the content of the slag fine powder is 70 parts to 80 parts.

2. The all-solid waste high-activity composite admixture according to claim 1, characterized in that: Relative to 100 parts by weight of the mixed-grinding fine powder, the steel slag tailings account for 80 to 90 parts, and the refined slag accounts for 10 to 20 parts.

3. The all-solid waste high-activity composite admixture according to claim 1, characterized in that: The steel slag tailings meet the following characteristics: MFe content is not greater than 1% by weight, binary basicity is not less than 3, and particle size is less than 5 mm.

4. The all-solid waste high-activity composite admixture according to claim 1, characterized in that: The mixed-grinding micropowder meets the following characteristics: specific surface area 400m 2 / kg~500m 2 / kg, 28d activity index is not less than 80%, moisture content is less than 1%.

5. The all-solid waste high-activity composite admixture according to claim 1 or 4, characterized in that: The chemical components of the mixed-grinding micropowder include: CaO, SiO2, Al2O3, MgO, SO3 and Cl; among them, in terms of mass fraction, The content of CaO is 30% to 50%, the content of SiO2 is 10% to 25%, the content of Al2O3 is 5% to 10%, the content of MgO is 5% to 8%, the content of SO3 is 0 to 3%, and the content of Cl is 0 to 0.06%.

6. The all-solid waste high-activity composite admixture according to claim 1, characterized in that: The slag powder meets the following characteristics: specific surface area 380m 2 / kg~450m 2 / kg, 28d activity index is not less than 95%, moisture content is less than 1%.

7. The all-solid waste high-activity composite admixture according to claim 1 or 6, characterized in that: The chemical components of the slag powder include: CaO, SiO2, Al2O3, MgO, SO3 and Cl; among them, in terms of mass fraction, The content of CaO is 30% to 50%, the content of SiO2 is 20% to 35%, the content of Al2O3 is 10% to 20%, the content of MgO is 8% to 12%, the content of SO3 is 0 to 3%, and the content of Cl is 0 to 0.06%.

8. A method for preparing the all-solid waste high-activity composite admixture according to any one of claims 1 to 7, characterized in that: The method comprises: The steel slag tailings are premixed with the refined slag and then ground to obtain homogenized mixed-ground micro powder; Mixing the homogenized mixed-grinding micropowder with slag micropowder to obtain a mixture; The mixed material is subjected to secondary homogenization treatment to obtain a fully solid waste high-activity composite admixture.

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