CaO-MgO-SiO2 system environment carbonization regulating agent and preparation method thereof

Abstract

The invention relates to a CaO-MgO-SiO2 system environment carbonization regulating agent and a preparation method thereof, belongs to the technical field of cementing materials, and relates to a solid waste recycling technology. The carbonization regulating agent is prepared from C7MS4, C5MS3, C3MS2, C2MS2, CMS, C2S, CS and C3S2. The carbonization regulating agent provided by the invention is a high-silicon mineral phase set which takes CaO-MgO-SiO2 minerals as main materials and has carbonization activity, and the carbonization regulation under environmental conditions is carried out through mineral matching according to the carbonization characteristics and behaviors of the minerals. The method has the main advantages that energy conservation and emission reduction are achieved in the production process, the requirement for the grade of calcium raw materials is lowered, and the limitation that magnesium-rich materials are prone to causing poor cement stone volume stability due to excessive MgO and application of the magnesium-rich materials in traditional cement is broken through; in addition, carbon mineralization is utilized to cause these absorbed CO2 to achieve a carbon sequestration effect.

Description

Technical Field

[0001] The invention relates to a CaO-MgO-SiO2 system environmental carbonization regulator and a preparation method thereof, belonging to the technical field of gelling materials and relating to solid waste resource technology. Background Art

[0002] Carbon dioxide capture, storage and utilization (CCUS) technology is considered to be the most effective method to control anthropogenic carbon emissions and mitigate climate change, and cement industry carbon storage and utilization technology is a large-scale, economically efficient CO2 utilization technology. In recent years, with the continuous development of the cement industry, the consumption of high-quality limestone has increased, and its storage has gradually decreased. The low-grade limestone is expected to become the norm, and high-magnesium limestone is the most widely used. At the same time, a large amount of industrial solid waste residues are generated in the process of human industrial production. The increasing amount of these waste residues directly endangers the property and human life safety near the slag dump, poses a serious threat to the environment and resources, and is difficult to be effectively utilized. Summary of the invention In view of the problems existing in the prior art, the present invention provides a CaO-MgO-SiO2 system environmental carbonization regulator, which is for efficiently utilizing a variety of solid wastes and high-magnesium limestone to produce clinker, can consume the stock of high-magnesium limestone, and promote the resource utilization of high-magnesium limestone and the functional utilization of MgO.

[0003] The present invention also provides a method for preparing the carbonization regulator containing the CaO-MgO-SiO2 mineral. The method has a simple process flow, consumes a large amount of solid waste, and can carry out industrial production of solid waste resources.

[0004] The technical solution adopted by the present invention to achieve the above-mentioned purpose is: The present invention provides a carbonization regulator for a CaO-MgO-SiO2 system environment, wherein the carbonization regulator comprises C7MS4, C5MS3, C3MS2, C2MS2, CMS, C2S, CS and C3S2.

[0005] Preferably, the mineral composition percentage of the carbonization regulator is: C7MS4: 5-57%, C5MS3: 0-15%, C3MS2: 15-75%, C2MS2: 3-45%, CMS: 0-50%, C2S: 8-55%, CS: 0-10%, C3S2: 0-10%.

[0006] Preferably, the raw material oxide composition percentages of the cement clinker are: CaO: 5-42%, SiO2: 26-61%, MgO: 25-65%, Al2O3: 1-10%, Fe2O3: 2-4%.

[0007] Preferably, the raw material composition percentages of low-grade / non-traditional raw materials of the cement clinker are: high-magnesium limestone: 10-55%, magnesium slag: 30-70%, ferrochrome slag: 5-35%, and fly ash 2-7%.

[0008] The present invention also provides a method for preparing the above-mentioned CaO-MgO-SiO2 system environmental carbonization regulator, which is characterized by comprising the following steps: a) Grinding the raw materials according to the formula, mixing and homogenizing to obtain powdered raw materials; b) The powdered raw material is pressed into tablets, dried, and then calcined at a heat preservation temperature. After the calcination, the powdered raw material is taken out and rapidly cooled, and then ground and sieved to obtain a CaO-MgO-SiO2 system environmental carbonization regulator.

[0009] Preferably, in step (a), the ingredients are calculated and designed according to the (Ca+Mg) / Si ratio.

[0010] Preferably, in step (b), the heat preservation calcination is carried out at 1000-1200° C. for 30-120 min.

[0011] Preferably, in step (b), the mesh size of the sieving is 200 meshes.

[0012] The present invention aims to prepare a carbonization regulator containing CaO-MgO-SiO2 minerals by utilizing solid waste and high-magnesium limestone, which can protect the environment and generate economic benefits, and has great potential.

[0013] The carbonization regulator provided by the present invention is a high-silicon mineral phase assembly with carbonization activity, mainly CaO-MgO-SiO2 minerals, and the carbonization is regulated under environmental conditions through mineral matching according to the carbonization characteristics and behaviors of these minerals. Its advantages mainly lie in energy saving and emission reduction in the production process, reduced requirements for the grade of calcium raw materials, and breaking the limitation of magnesium-rich materials in traditional cement due to excessive MgO, which easily causes poor volume stability of cement stone; in addition, the use of carbon mineralization enables these CO2 absorption to achieve carbon sequestration effect.

[0014] The beneficial effects of the present invention are: (1) The present invention uses high-magnesium limestone, which is currently underutilized, and other industrial solid wastes to convert it into a CaO-MgO-SiO2 system environmental carbonization regulator through high-temperature calcination. C7MS4, C5MS3, C3MS2, C2MS2, CMS and C2S in the carbonization regulator give the material good carbonization activity to exhibit good mechanical properties; (2) The present invention not only effectively utilizes a large amount of industrial solid waste and high-magnesium limestone, but also uses the CaO-MgO-SiO2 system environmental carbonization regulator to prepare a carbon-fixing cement system with excellent mechanical properties and durability, production economic benefits, huge market potential, and is of great significance. DETAILED DESCRIPTION

[0015] The technical solution of the present invention is further described in detail below in conjunction with specific embodiments.

[0016] Example 1 The composition percentage of the environmental carbonization regulator in the CaO-MgO-SiO2 system is: C7MS4: 40%, C5MS3: 15%, C3MS2: 30%, C2MS2: 5%, C2S: 10%.

[0017] The specific preparation method is as follows: According to the mineral composition, the raw materials were weighed and ground, mixed evenly, and powdered cement raw materials were obtained. The raw materials were pressed into round cake specimens with a size of φ60mm×10mm, dried, and then calcined in a high-temperature furnace at 1300℃, kept warm for 60min, taken out and quenched, ground through a 200-mesh sieve, and cement clinker was obtained. The mechanical properties of the prepared clinker are shown in Table 1.

[0018] Example 2 The composition percentage of the environmental carbonization regulator in the CaO-MgO-SiO2 system is: C7MS4: 12%, C5MS3: 2%, C3MS2: 55%, C2MS2: 10%, CMS: 11%, C2S: 8%, CS: 2%.

[0019] The specific preparation method is as follows: The raw materials were weighed and calculated according to the mineral composition, ground and mixed evenly to obtain powdered cement raw materials, which were pressed into round cake specimens with a size of φ60mm×10mm, dried, and then calcined in a high-temperature furnace at 1330℃, kept warm for 60min, taken out and quenched, ground and passed through a 200-mesh sieve to obtain cement clinker. The mechanical properties of the prepared clinker are shown in Table 1.

[0020] Example 3 The composition percentage of the environmental carbonization regulator in the CaO-MgO-SiO2 system is: C7MS4: 6%, C3MS2: 38%, C2MS2: 25%, CMS: 12%, C2S: 16%, CS: 1%, C3S2: 2%.

[0021] The specific preparation method is as follows: The raw materials were weighed and calculated according to the mineral composition, ground and mixed evenly to obtain powdered cement raw materials, which were pressed into round cake specimens with a size of φ60mm×10mm, dried, and then calcined in a high-temperature furnace at 1350℃, kept warm for 90min, taken out and quenched, ground and passed through a 200-mesh sieve to obtain cement clinker. The mechanical properties of the prepared clinker are shown in Table 1.

[0022] Table 1 Carbonization rate of samples at different ages Table 2 Carbon capture capacity of samples at different ages Table 3 Mechanical properties of samples at different ages

Claims

1. A CaO-MgO-SiO2 system environmental carbonization regulator, characterized in that: The carbonization regulators include C7MS4, C5MS3, C3MS2, C2MS2, CMS, C2S, CS and C3S2.

2. The CaO-MgO-SiO2 system environmental carbonization regulator according to claim 1, characterized in that: The mineral composition percentages of the carbonization regulator are: C7MS4: 5-57%, C5MS3: 0-15%, C3MS2: 15-75%, C2MS2: 3-45%, CMS: 0-50%, C2S: 8-55%, CS: 0-10%, C3S2: 0-10%.

3. The CaO-MgO-SiO2 system environmental carbonization regulator according to claim 1 or 2, characterized in that: The raw material oxide composition percentages of the cement clinker are: CaO: 5-42%, SiO2: 26-61%, MgO: 25-65%, Al2O3: 1-10%, and Fe2O3: 2-4%.

4. The CaO-MgO-SiO2 system environmental carbonization regulator according to any one of claims 1 to 3, characterized in that: The raw material composition percentages of low-grade / non-traditional raw materials of the cement clinker are as follows: high-magnesium limestone: 10-55%, magnesium slag: 30-70%, ferrochrome slag: 5-35%, and fly ash: 2-7%.

5. A method for preparing the CaO-MgO-SiO2 system environmental carbonization regulator according to any one of claims 1 to 4, characterized in that: The following steps are included: a) Grinding the raw materials according to the formula, mixing and homogenizing to obtain powdered raw materials; b) The powdered raw material is pressed into tablets, dried, and then calcined at a heat preservation temperature. After the calcination, the powdered raw material is taken out and rapidly cooled, and then ground and sieved to obtain a CaO-MgO-SiO2 system environmental carbonization regulator.

6. The preparation method according to claim 5, characterized in that: In step (a), the ingredients are calculated and designed according to the (Ca+Mg) / Si ratio.

7. The preparation method according to claim 5 or 6, characterized in that: In step (b), the heat preservation calcination is to keep the temperature at 1000-1200° C. for 30-120 min.

8. The preparation method according to claim 5 or 7, characterized in that: In step (b), the mesh size of the sieving is 200 meshes.

Images