Solid waste-based high-erosion-resistant ferrum aluminate cement clinker, raw material and preparation method thereof

Abstract

The application discloses a solid waste-based high-erosion-resistant ferrum aluminate cement clinker, a raw material thereof and a preparation method. The cement clinker comprises the following components: C2S 15-45 wt.%, modified calcium sulphoaluminate mineral 20-40 wt.%, modified iron phase mineral 15-25 wt.%, C5S2$ 5-10 wt.%, spinel inert mineral 0.5-3 wt.%, CaSO4 3-10 wt.%, and inevitable impurities in the remainder. The application introduces specific mineral phase stable solid waste components into a solid waste-based raw material system, forms a new component system mainly composed of C2S, modified calcium sulphoaluminate mineral, modified iron phase mineral and C5S2$, overcomes the problem that it is difficult to stably obtain a belite-sulphoaluminate cementitious material system by taking steel slag and recycled micro powder as main raw materials, and the new component system has excellent erosion resistance to sulphate and chloride.

Description

Technical Field

[0001] This invention relates to the field of cement materials, specifically to a solid waste-based high corrosion-resistant ferroaluminate cement clinker and its raw materials and preparation method. Background Technology

[0002] The information disclosed in this background section is intended only to enhance understanding of the overall background of the invention and is not necessarily to be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.

[0003] Belite-sulfoaluminate cementitious materials have attracted attention due to their combination of lower clinker firing temperatures and faster early strength development. The clinker minerals in this type of system typically include not only calcium sulfoaluminate phases (such as anhydrous calcium sulfoaluminate C4A3$) and dicalcium silicate (C2S), but may also form sulfur-containing silicate phases, such as Ca5(SiO4)2SO4 (often denoted as C5S2$). Under conditions of added or internal calcium sulfate, the rapid hydration of C4A3$ and the continuous hydration of C2S can, to some extent, achieve complementary strength development. Simultaneously, as a sulfur-containing silicate phase, the reaction behavior of C5S2$ is closely related to sulfate supply and the presence of aluminate / aluminoferrite phases, significantly influencing the hydration process and product composition of the system. The coexistence of these multiple mineral phases provides a basis for the synergistic regulation of the system's hydration reaction and is closely related to the material's durability.

[0004] Steel slag typically contains Ca, Si, and Fe, along with certain amounts of Mg and Mn, serving as a source of calcium and iron and influencing the formation of the iron phase and related minerals. Recycled micropowders (such as construction waste recycled powder and recycled concrete powder) typically provide Si, Al, and Ca, serving as a source of silica and alumina and participating in the formation of the belite and sulfoaluminate phases. This invention attempts to prepare belite-sulfoaluminate cementitious materials using the aforementioned industrial solid wastes as raw materials. However, this invention has found that using steel slag and recycled micropowders as the main raw materials under conventional conditions makes it difficult to stably calcine a target mineral composition containing C2S, C4A3, C5S2, and the iron phase simultaneously, and the resulting composition system struggles to achieve synergy in the hydration process and high corrosion resistance. Summary of the Invention

[0005] This invention provides a solid waste-based high corrosion-resistant ferroaluminate cement clinker, its raw materials, and preparation method. By introducing specific mineral-phase stabilizing solid waste components into the solid waste-based raw material system, a novel component system is formed, mainly composed of C2S, modified calcium sulfoaluminate minerals, modified iron-phase minerals, and C5S2S. This not only overcomes the problem of difficulty in stably obtaining belite-sulfoaluminate cementitious material systems using steel slag and recycled micro powder as the main raw materials, but also exhibits excellent resistance to sulfates, chlorides, and other corrosion. Specifically, the technical solution of this invention is as follows.

[0006] First, this invention provides a solid waste-based high corrosion-resistant aluminoferrite cement clinker, comprising the following components: C2S 15~45wt.%, modified calcium sulfoaluminate mineral 20~40wt.%, modified iron phase mineral 15~25wt.%, C5S2S 5~10wt.%, spinel inert mineral 0.5~3wt.%, CaSO4 3~10wt.%, with the balance being unavoidable impurities. The modified calcium sulfoaluminate mineral is formed by the substitution of some aluminum elements with iron and manganese, and has the chemical formula Ca4(Al2O3). 6-x-y Fe x Mn y )O 12 SO4, and 0.05≤x≤2.50, 0.02≤y≤0.10. The modified iron-phase mineral is a calcium iron aluminate solid solution with the chemical formula Ca2(Al2O3). 1-a-b Fe a Mn b The chemical formula of the spinel inert mineral is MgCr2O4, where 0.1 ≤ a ≤ 0.60, 0.05 ≤ b ≤ 0.10, and a + b ≤ 0.66.

[0007] Furthermore, the cement clinker composition also includes externally added calcium sulfate setting regulator. Optionally, the amount of calcium sulfate setting regulator is 3-7 wt.% of the cement clinker mass.

[0008] Furthermore, the calcium sulfate setting agent includes at least one of the following: chemically pure gypsum, natural gypsum, anhydrous gypsum, and solid waste gypsum. Optionally, the solid waste gypsum includes at least one of the following: desulfurized gypsum, phosphogypsum, fluorogypsum, and titanium gypsum.

[0009] Secondly, the present invention provides a raw meal for preparing the solid waste-based high corrosion-resistant aluminoferrite cement clinker, comprising the following components: 11.53~54.14 parts by weight of steel slag, 5.16~13.57 parts by weight of recycled micro powder, 13.09~22.09 parts by weight of sulfate, 11.21~36.02 parts by weight of calcium correcting material, 6.79~32.97 parts by weight of alumina correcting material, and 1.1~1.51 parts by weight of borosilicate glass component.

[0010] Furthermore, the steel slag includes at least one of converter steel slag, electric furnace steel slag, etc.

[0011] Furthermore, the recycled micro powder includes at least one of the following: waste concrete powder, waste clay brick powder, etc.

[0012] Furthermore, the sulfate includes at least one of the following: natural gypsum, anhydrous gypsum, desulfurized gypsum, phosphogypsum, fluorogypsum, and mirabilite.

[0013] Furthermore, the calcium-based raw material includes at least one of limestone, carbide slag, quicklime, etc.

[0014] Furthermore, the aluminum raw materials include at least one of bauxite, high-alumina fly ash, and aluminum slag.

[0015] Furthermore, based on B2O3 equivalent, the mass fraction of B2O3 in the borosilicate glass solid waste is 7.6~10.7%.

[0016] Furthermore, the borosilicate glass component includes at least one of the following: glass fiber powder, borosilicate glass powder, and low-alkali glass polishing waste residue for photovoltaics or displays. Preferably, the total content of Na2O and K2O in the borosilicate glass component is not higher than 3 wt.%, which helps to avoid the risk of uncontrolled liquid phase viscosity, free alkali enrichment, and subsequent efflorescence caused by the formation of excessive high-alkali liquid phase / alkali sulfate phase during clinker firing. This is beneficial to the stable formation of the target mineral phase and the densification of the pore structure and improvement of corrosion resistance after hydration.

[0017] Finally, the present invention provides a method for preparing the solid waste-based high corrosion-resistant aluminoferrite cement clinker, comprising the following steps: mixing the components of the raw material and then calcining it; after completion, rapidly cooling the calcined product and then grinding it to obtain the desired product.

[0018] Further, the calcination treatment is carried out at a temperature of 1150~1270℃ for a time of 10~60min. Optionally, the rapid cooling rate is ≥100℃ / min.

[0019] Compared with the prior art, the technical solution of the present invention has at least the following beneficial effects: To address the difficulty in stably obtaining belite-sulfoaluminate cementitious material systems using steel slag and recycled micronized powder as the main raw materials, this invention introduces a boron-containing glass component as a mineral phase stabilizer. By utilizing the softening of this boron-containing glass within a firing temperature range of 1150–1270°C to form a boron-rich glassy liquid phase, the viscosity of the resulting clinker liquid phase is reduced, and the content of Ca, Si, Al, Fe, Mn, and SO4 is increased. 2-The migration and reaction uniformity of related ions lower the nucleation energy barrier of modified calcium sulfoaluminate minerals, modified iron phase minerals, and calcium sulfosilicate minerals, thereby stabilizing the synergistic formation pathway of the aforementioned target minerals and suppressing the formation of unfavorable phases. This effectively improves the stability of the clinker mineral composition and forms a novel clinker composition system containing modified calcium sulfoaluminate minerals and modified iron phase minerals. The boron-containing glass provides some boron element that enters the lattice of the C2S and / or C5S2O3 mineral phases or forms trace amounts of CaO–B2O3 borate phases, thus achieving stable coexistence of the target mineral phases without significantly sacrificing strength. On the one hand, during the initial hydration stage, the modified calcium sulfoaluminate minerals rapidly hydrate in the presence of sulfate to generate an early framework dominated by AFt; simultaneously, the modified iron phase minerals are released and provide ionic components that can participate in the reaction, making the formation of AFt and iron-aluminate gel more continuous and the transformation more controllable; subsequently, C2S and C5S2S continue to hydrate to generate C-(A,F)-SH gels and fill the pores, achieving pore structure refinement and improved corrosion resistance. Subsequently, C2S and C5S2S provide continuous hydration and later densification, further refining the pore structure and improving structural stability and long-term performance. On the other hand, the solid waste-based high corrosion-resistant ferroaluminate cement clinker of this invention exhibits excellent resistance to corrosive media such as sulfates, chlorides, and complex salts. This is because the modified iron-phase minerals and modified calcium sulfoaluminate minerals release Fe and Mn elements during hydration. During hydration, these two elements jointly participate in the formation of iron-aluminum hydration products, which is beneficial for product structure densification and enhances the binding and fixation ability against corrosive ions. They enter the iron-containing hydration products C3(A,F)H6, (A,F)H3-type hydration gels, and iron-containing AFt and AFm products formed by the cement clinker of this invention through solidification or substitution. This not only helps fill pores and promote microstructure densification but also enhances the resistance to Cl... - SO4 2- The chemical binding and fixation ability of corrosive ions is enhanced, thereby reducing the migration of corrosive ions in the pore solution. Simultaneously, the spinel inert mineral (MgCr2O4), as a stable microcrystalline framework phase, maintains chemical stability under corrosive conditions and inhibits ion migration, enabling the cement clinker of this invention to exhibit higher strength retention, lower ion penetration and diffusion levels, and better volume stability under corrosive conditions. Attached Figure Description

[0020] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention and do not constitute an undue limitation of the invention.

[0021] Figure 1 The image shows a sample of solid waste-based high corrosion-resistant aluminoferrite cement clinker prepared in Example 1 below.

[0022] Figure 2The image shows the XRD pattern of the solid waste-based high corrosion-resistant aluminoferrite cement clinker prepared in Example 1 below.

[0023] Figure 3 The image shows a sample of solid waste-based high corrosion-resistant aluminoferrite cement clinker prepared in Example 2 below.

[0024] Figure 4 The image shows the XRD pattern of the solid waste-based high corrosion-resistant aluminoferrite cement clinker prepared in Example 2 below.

[0025] Figure 5 The image shows a sample of solid waste-based high corrosion-resistant aluminoferrite cement clinker prepared in Example 3 below.

[0026] Figure 6 The image shows the XRD pattern of the solid waste-based high corrosion-resistant aluminoferrite cement clinker prepared in Example 3 below.

[0027] Figure 7 The image shows a sample of solid waste-based high corrosion-resistant aluminoferrite cement clinker prepared in Example 4 below.

[0028] Figure 8 The image shows a sample of solid waste-based high corrosion-resistant aluminoferrite cement clinker prepared in Example 5 below.

[0029] Figure 9 The image shows a sample of solid waste-based high corrosion-resistant aluminoferrite cement clinker prepared in Example 6 below.

[0030] Figure 10 The image shows a sample of solid waste-based high corrosion-resistant aluminoferrite cement clinker prepared in Example 7 below. Detailed Implementation

[0031] The technical solution of the present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Experimental methods in the following embodiments that do not specify specific conditions are generally performed under conventional conditions or as recommended by the manufacturer.

[0032] Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as those skilled in the art. The reagents or raw materials used in this invention are readily available through conventional means. Unless otherwise specified, the reagents or raw materials used in this invention are used in accordance with conventional methods in the art or according to the product instructions. The technical solution of this invention will now be further described in conjunction with the accompanying drawings and specific embodiments.

[0033] Example 1: A method for preparing solid waste-based high corrosion-resistant aluminoferrite cement clinker, comprising the following steps: (1) The following raw materials are used: 39.16 parts by weight of converter steel slag powder, 5.16 parts by weight of recycled micro powder made from waste concrete, 16.66 parts by weight of natural gypsum, 21.71 parts by weight of limestone, 15.80 parts by weight of bauxite, and 1.51 parts by weight of borosilicate glass powder. The fineness of the converter steel slag powder and the recycled micro powder is 400 mesh. The mass fraction of B2O3 in the borosilicate glass powder is 10.7 wt.% based on B2O3 equivalent.

[0034] (2) After mixing all the components of the above raw materials, heat them to 1200℃ at a heating rate of 10℃ / min and calcine for 45min. After completion, rapidly cool the calcined product to room temperature at a cooling rate of ≥100℃ / min, and then grind it at a rate of 500r / min for 0.5 hours to obtain cement clinker (e.g. Figure 1 (As shown).

[0035] The cement clinker prepared in this embodiment was subjected to XRD testing (e.g., Figure 2 As shown in the figure, Rietveld quantitative analysis was then performed. The results showed that the mineral composition of the clinker prepared in this embodiment included: C2S 32.73 wt.%, modified calcium sulfoaluminate mineral 26.91 wt.%, modified iron phase mineral 20.48 wt.%, C5S2S 7.34 wt.%, spinel inert mineral 1.12 wt.%, CaSO4 8.56 wt.%, with the balance being unavoidable impurities. The modified calcium sulfoaluminate mineral has the chemical formula Ca4(Al2O3)2. 4.33 Fe 1.6 Mn 0.07 )O 12 SO4, the chemical formula of the modified iron-phase mineral is Ca2(Al) 0.46 Fe 0.5 Mn 0.04 The chemical formula of the spinel inert mineral is MgCr2O4.

[0036] Performance testing: (1) The cement clinker of this embodiment was ground and passed through a 200-mesh sieve to obtain clinker powder, and then 5% by weight of dihydrate gypsum was added to obtain cement powder. The cement powder was made into 40×40×160mm mortar specimens (mortar-to-cement ratio 1:3, water-to-cement ratio 0.50) according to GB / T 17671, and the compressive strength at 3d, 7d, and 28d was tested. (2) The K method in GB / T 749-2008 was used to determine the sulfate resistance (K value) of the mortar specimens. (3) The chloride ion migration coefficient DRCM of the mortar specimens was tested using the RCM method, and the results are shown in Table 1 below.

[0037] Table 1

[0038] Example 2: A method for preparing solid waste-based high corrosion-resistant aluminoferrite cement clinker, comprising the following steps: (1) The following raw materials were used: 54.14 parts by weight of electric furnace steel slag, 13.57 parts by weight of recycled micro powder made from waste concrete, 13.09 parts by weight of anhydrous gypsum, 11.21 parts by weight of limestone, 6.79 parts by weight of bauxite, and 1.2 parts by weight of borosilicate glass powder. The fineness of the electric furnace steel slag and the recycled micro powder was 400 mesh. The mass fraction of B2O3 in the borosilicate glass powder was 8.90 wt.% based on B2O3 equivalent.

[0039] (2) After mixing all the components of the above raw materials, heat them to 1270℃ at a heating rate of 10℃ / min and calcine for 10min. After completion, rapidly cool the calcined product to room temperature at a cooling rate of ≥100℃ / min, and then grind it at a rate of 450r / min for 0.6 hours to obtain cement clinker (e.g. Figure 3 (As shown).

[0040] The cement clinker prepared in this embodiment was subjected to XRD testing (e.g., Figure 4 As shown in the figure), Rietveld quantitative analysis was then performed. The results showed that the mineral composition of the clinker prepared in this embodiment included: C2S 45.06 wt.%, modified calcium sulfoaluminate mineral 21.27 wt.%, modified iron phase mineral 14.97 wt.%, C5S2S 6.18 wt.%, spinel inert mineral 3.03 wt.%, CaSO4 5.44 wt.%, with the balance being unavoidable impurities. The modified calcium sulfoaluminate mineral has the chemical formula Ca4(Al2O3)2. 3.47 Fe 2.5 Mn 0.03 )O 12 SO4, the chemical formula of the modified iron-phase mineral is Ca2(Al) 0.35 Fe 0.6 Mn 0.06 The chemical formula of the spinel inert mineral is MgCr2O4.

[0041] Performance testing: The various performance indicators of the cement clinker in this embodiment were tested using the same method as in Example 1 above, and the results are shown in Table 2 below.

[0042] Table 2

[0043] Example 3: A method for preparing high corrosion-resistant aluminoferrite cement clinker based on solid waste, comprising the following steps: (1) The following raw materials are used: 11.93 parts by weight of converter steel slag powder, 5.6 parts by weight of recycled micro powder made from waste concrete, 22.09 parts by weight of desulfurized gypsum, 27.86 parts by weight of calcium carbide slag, 31.22 parts by weight of aluminum slag, and 1.3 parts by weight of borosilicate glass powder. The fineness of the converter steel slag powder and the recycled micro powder is 400 mesh. The mass fraction of B2O3 in the borosilicate glass powder is 10.03 wt.% based on B2O3 equivalent.

[0044] (2) After mixing all the components of the above raw materials, heat them to 1150℃ at a heating rate of 10℃ / min and calcine for 60min. After completion, rapidly cool the calcined product to room temperature at a cooling rate of ≥100℃ / min, and then grind it at a rate of 600r / min for 0.2 hours to obtain cement clinker (e.g. Figure 5 (As shown).

[0045] The cement clinker prepared in this embodiment was subjected to XRD testing (e.g., Figure 6 As shown in the figure, Rietveld quantitative analysis was then performed. The results showed that the mineral composition of the clinker prepared in this embodiment included: C2S 15.04 wt.%, modified calcium sulfoaluminate mineral 39.95 wt.%, modified iron phase mineral 18.22 wt.%, C5S2S 9.98 wt.%, spinel inert mineral 2.67 wt.%, CaSO4 10.02 wt.%, with the balance being unavoidable impurities. The modified calcium sulfoaluminate mineral has the chemical formula Ca4(Al2O3)2. 5.75 Fe 0.15 Mn 0.1 )O 12 SO4, the chemical formula of the modified iron-phase mineral is Ca2(Al) 0.8 Fe 0.1 Mn 0.1 The chemical formula of the spinel inert mineral is MgCr2O4.

[0046] Performance testing: The various performance indicators of the cement clinker in this embodiment were tested using the same method as in Example 1 above, and the results are shown in Table 3 below.

[0047] Table 3

[0048] Example 4: A solid waste-based high corrosion-resistant aluminoferrite cement clinker and its preparation method, comprising the following steps: (1) The following raw materials were used: 11.53 parts by weight of electric furnace steel slag, 5.20 parts by weight of recycled micro powder made from waste clay brick powder, 13.18 parts by weight of phosphogypsum, 36.02 parts by weight of quicklime, 32.97 parts by weight of high-alumina fly ash, and 1.1 parts by weight of borosilicate glass powder. The fineness of the electric furnace steel slag powder and the recycled micro powder was 400 mesh. The mass fraction of B2O3 in the borosilicate glass powder was 7.6 wt.% based on B2O3 equivalent.

[0049] (2) After mixing all the components of the above raw materials, heat them to 1180℃ at a heating rate of 10℃ / min and calcine for 30min. After completion, rapidly cool the calcined product to room temperature at a cooling rate of ≥100℃ / min, and then grind it at a rate of 400r / min for 1 hour to obtain cement clinker (e.g. Figure 7 (As shown).

[0050] The cement clinker prepared in this embodiment was subjected to XRD testing, followed by Rietveld quantitative analysis. The results showed that the mineral composition of the clinker prepared in this embodiment included: C2S 38.19 wt.%, modified calcium sulfoaluminate mineral 20.07 wt.%, modified iron phase mineral 25.01 wt.%, C5S2S 4.98 wt.%, spinel inert mineral 0.51 wt.%, CaSO4 3.04 wt.%, with the balance being unavoidable impurities. The modified calcium sulfoaluminate mineral has the chemical formula Ca4(Al2O3)2. 4.78 Fe 0.2 Mn 0.02 )O 12 SO4, the chemical formula of the modified iron-phase mineral is Ca2(Al) 0.62 Fe 0.3 Mn 0.08 The chemical formula of the spinel inert mineral is MgCr2O4.

[0051] Performance testing: The various performance indicators of the cement clinker in this embodiment were tested using the same method as in Example 1 above, and the results are shown in Table 4 below.

[0052] Table 4

[0053] Example 5: A method for preparing solid waste-based high corrosion-resistant aluminoferrite cement clinker, comprising the following steps: (1) Take the following raw materials: 39.16 parts by weight of converter steel slag powder, 5.16 parts by weight of recycled micro powder made from waste concrete, 16.66 parts by weight of natural gypsum, 21.71 parts by weight of quicklime, and 15.80 parts by weight of bauxite. The fineness of the converter steel slag powder and the recycled micro powder is 400 mesh.

[0054] (2) After mixing all the components of the above raw materials, heat them to 1200℃ at a heating rate of 10℃ / min and calcine for 45min. After completion, rapidly cool the calcined product to room temperature at a cooling rate of ≥100℃ / min, and then grind it at a rate of 500r / min for 0.5 hours to obtain cement clinker (e.g. Figure 8 (As shown).

[0055] The cement clinker prepared in this embodiment was subjected to XRD testing, followed by Rietveld quantitative analysis. The results showed that the mineral composition of the clinker prepared in this embodiment included: C2S 36.10 wt.%, modified calcium sulfoaluminate mineral 23.41 wt.%, modified iron phase mineral 18.22 wt.%, C5S2S 4.57 wt.%, spinel inert mineral 1.10 wt.%, CaSO4 8.52 wt.%, with the balance being unavoidable impurities. The modified calcium sulfoaluminate mineral has the chemical formula Ca4(Al2O3)2. 5.40 Fe 0.55 Mn 0.05 )O 12 SO4, the chemical formula of the modified iron-phase mineral is Ca2(Al) 0.0.7 Fe 0.29 Mn 0.01 The chemical formula of the spinel inert mineral is MgCr2O4.

[0056] Performance testing: The various performance indicators of the cement clinker in this embodiment were tested using the same method as in Example 1 above, and the results are shown in Table 5 below.

[0057] Table 5

[0058] Example 6: A method for preparing solid waste-based high corrosion-resistant aluminoferrite cement clinker, comprising the following steps: (1) The following raw materials were used: 58.32 parts by weight of electric furnace steel slag, 11.48 parts by weight of recycled micro powder made from waste concrete, 13.09 parts by weight of anhydrous gypsum, 9.71 parts by weight of limestone, 6.2 parts by weight of bauxite, and 1.2 parts by weight of borosilicate glass powder. The fineness of the electric furnace steel slag and the recycled micro powder was 400 mesh. The mass fraction of B2O3 in the borosilicate glass powder was 8.90 wt.% based on B2O3 equivalent.

[0059] (2) After mixing all the components of the above raw materials, heat them to 1270℃ at a heating rate of 10℃ / min and calcine for 10min. After completion, rapidly cool the calcined product to room temperature at a cooling rate of ≥100℃ / min, and then grind it at a rate of 450r / min for 0.6 hours to obtain cement clinker (e.g. Figure 9 (As shown).

[0060] The cement clinker prepared in this embodiment was subjected to XRD testing, followed by Rietveld quantitative analysis. The results showed that the mineral composition of the clinker prepared in this embodiment included: C2S 45.06 wt.%, modified calcium sulfoaluminate mineral 21.27 wt.%, modified iron phase mineral 14.97 wt.%, C5S2S 6.18 wt.%, spinel inert mineral 3.03 wt.%, CaSO4 5.44 wt.%, with the balance being unavoidable impurities. The modified calcium sulfoaluminate mineral has the chemical formula Ca4(Al2O3)2. 3.06 Fe 2.8 Mn 0.14 )O 12 SO4, the chemical formula of the modified iron-phase mineral is Ca2(Al) 0.35 Fe 0.6 Mn 0.06 The chemical formula of the spinel inert mineral is MgCr2O4.

[0061] Performance testing: The various performance indicators of the cement clinker in this embodiment were tested using the same method as in Example 1 above, and the results are shown in Table 6 below.

[0062] Table 6

[0063] Example 7: A method for preparing high corrosion-resistant aluminoferrite cement clinker based on solid waste, comprising the following steps: (1) The following raw materials are used: 17.46 parts by weight of converter steel slag powder, 5.32 parts by weight of recycled micro powder made from waste concrete, 22.09 parts by weight of desulfurized gypsum, 28.63 parts by weight of calcium carbide slag, 25.20 parts by weight of aluminum slag, and 1.3 parts by weight of borosilicate glass powder. The fineness of the converter steel slag powder and the recycled micro powder is 400 mesh. The mass fraction of B2O3 in the borosilicate glass powder is 10.03 wt.% based on B2O3 equivalent.

[0064] (2) After mixing all the components of the above raw materials, heat them to 1150℃ at a heating rate of 10℃ / min and calcine for 60min. After completion, rapidly cool the calcined product to room temperature at a cooling rate of ≥100℃ / min, and then grind it at a rate of 600r / min for 0.2 hours to obtain cement clinker (e.g. Figure 10 (As shown).

[0065] The cement clinker prepared in this embodiment was subjected to XRD testing, followed by Rietveld quantitative analysis. The results showed that the mineral composition of the clinker prepared in this embodiment included: C2S 18.36 wt.%, modified calcium sulfoaluminate mineral 36.84 wt.%, modified iron phase mineral 19.75 wt.%, C5S2S 8.92 wt.%, spinel inert mineral 2.41 wt.%, CaSO4 8.43 wt.%, with the balance being unavoidable impurities. The modified calcium sulfoaluminate mineral has the chemical formula Ca4(Al2O3)2. 5.75 Fe 0.15 Mn 0.1 )O 12 SO4, the chemical formula of the modified iron-phase mineral is Ca2(Al) 0.25 Fe 0.62 Mn 0.13 The chemical formula of the spinel inert mineral is MgCr2O4.

[0066] Performance testing: The various performance indicators of the cement clinker in this embodiment were tested using the same method as in Example 1 above, and the results are shown in Table 7 below.

[0067] Table 7

[0068] The above are merely some preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A solid waste-based high corrosion-resistant aluminoferrite cement clinker, characterized in that, The composition includes the following components: C2S 15~45 wt.%, modified calcium sulfoaluminate mineral 20~40 wt.%, modified iron phase mineral 15~25 wt.%, C5S2S 5~10 wt.%, spinel inert mineral 0.5~3 wt.%, CaSO4 3~10 wt.%, with the balance being unavoidable impurities; wherein: The modified calcium sulfoaluminate mineral is formed by replacing part of the calcium element with iron and manganese, and has the chemical formula Ca4(Al). 6-x- y Fe x Mn y )O 12 SO4, and 0.05≤x≤2.50, 0.02≤y≤0.10; The modified iron-phase mineral is a calcium iron aluminate solid solution with the chemical formula Ca2(Al2O3). 1-a-b Fe a Mn b )2O5, and 0.1≤a≤0.60, 0.05≤b≤0.10, a+b≤0.66; The chemical formula of the spinel inert mineral is MgCr2O4.

2. The solid waste-based high corrosion-resistant aluminoferrite cement clinker according to claim 1, characterized in that, The cement clinker also includes externally added calcium sulfate setting regulator; optionally, the amount of calcium sulfate setting regulator is 3 to 7 wt.% of the cement clinker mass.

3. The solid waste-based high corrosion-resistant aluminoferrite cement clinker according to claim 1 or 2, characterized in that, The calcium sulfate setting agent includes at least one of the following: chemically pure gypsum, natural gypsum, anhydrous gypsum, and solid waste gypsum; optionally, the solid waste gypsum includes at least one of the following: desulfurized gypsum, phosphogypsum, fluorogypsum, and titanium gypsum.

4. A raw meal for preparing the solid waste-based high corrosion-resistant aluminoferrite cement clinker according to any one of claims 1-3, characterized in that, It includes the following components: 11.53~54.14 parts by weight of steel slag, 5.16~13.57 parts by weight of recycled micro powder, 13.09~22.09 parts by weight of sulfate, 11.21~36.02 parts by weight of calcium correcting material, 6.79~32.97 parts by weight of aluminum correcting material, and 1.1~1.51 parts by weight of borosilicate glass component.

5. The raw meal for preparing the solid waste-based high corrosion-resistant aluminoferrite cement clinker according to claim 4, characterized in that, The steel slag includes at least one of the following: converter steel slag and electric furnace steel slag; Optionally, the recycled powder includes at least one of waste concrete powder and waste clay brick powder.

6. The raw meal for preparing the solid waste-based high corrosion-resistant aluminoferrite cement clinker according to claim 4, characterized in that, The sulfates include at least one of the following: natural gypsum, anhydrous gypsum, desulfurized gypsum, phosphogypsum, fluorogypsum, and mirabilite.

7. The raw meal for preparing the solid waste-based high corrosion-resistant aluminoferrite cement clinker according to claim 4, characterized in that, The calcium-based raw material includes at least one of limestone, carbide slag, and quicklime. Optionally, the aluminum raw material includes at least one of bauxite, high-alumina fly ash, and aluminum slag.

8. The raw meal for preparing the solid waste-based high corrosion-resistant aluminoferrite cement clinker according to any one of claims 4-7, characterized in that, Based on B2O3 equivalent, the mass fraction of B2O3 in the borosilicate glass solid waste is 7.6% to 10.7%. Optionally, the boron-containing glass component includes at least one of: glass fiber powder, borosilicate glass powder, and low-alkali glass polishing waste for photovoltaic or display applications; Preferably, the total content of Na2O and K2O in the borosilicate glass component is not higher than 3 wt.%.

9. The method for preparing solid waste-based high corrosion-resistant aluminoferrite cement clinker according to any one of claims 1-3, characterized in that, The process includes the following steps: mixing the components of the raw material according to any one of claims 4-8 and then calcining it; after completion, rapidly cooling the calcined product and then grinding it to obtain the final product.

10. The preparation method according to claim 9, characterized in that, The calcination treatment is carried out at a temperature of 1150~1270℃ for a time of 10~60 min; optionally, the rapid cooling rate is ≥100℃ / min.

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