Stepped separation and high-valued utilization-based steel slag full-quantitative treatment method and admixture

Abstract

The invention relates to a steel slag full-quantitative treatment method based on gradient separation and high-value utilization and an admixture, chemical agents do not need to be introduced in the technological process, and the method is environmentally friendly and remarkable in economic benefit. The final product is a high-value metal raw material and qualified cement, and the purposes of'drying and squeezing 'and zero emission of the steel slag are really achieved. The invention creatively develops an optimized cement formula which takes the final tailings, the desulfurization slag and the carbon sequestration slag as main raw materials of by-products in the whole steel slag treatment process. According to the formula, bulk consumption of solid waste is achieved, the performance of the produced cement completely meets or even is superior to the national standard (GB 175-2007) through the synergistic effect of all the components, and unification of'waste turning into wealth 'and'high-value utilization' is achieved. And finally, the tailings, the desulfurization residues and the carbon fixation residues are all used for preparing the cement admixture, so that zero emission and full-quantitative resource utilization of solid wastes are realized. The formula system is flexible, cement products with multiple labels are stably produced, and the market adaptability is high.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of metallurgical solid waste resource utilization, and particularly relates to a steel slag full-quantitative treatment method based on gradient separation and high-value utilization and a blended material. BACKGROUND

[0002] Steel slag is a large amount of solid waste generated in the steel smelting process, and its main chemical components include CaO, SiO2, FeO, Fe2O3, MgO, etc. Steel slag contains a certain amount of metallic iron, and how to efficiently recover these valuable metals is one of the keys to resource utilization. However, the existing steel slag treatment technology often has problems such as long process flow, low metal recovery rate, low product added value, secondary pollution, etc.

[0003] Patent CN113149494A discloses a method for improving the stability of steel slag by using acetic acid and using it as a concrete fine aggregate, but does not involve metal recovery. Patent CN117209186A utilizes hot steel slag to decompose calcium carbonate for resource utilization, but the energy consumption is high. Patent CN115354091A proposes a classification processing concept, but the process flow is complex, and there is a lack of effective scheme for efficient separation and utilization of fine and micro-particle steel slag.

[0004] Therefore, there is an urgent need to develop a new method for efficient, clean and full-quantitative steel slag resource utilization, which can recover metals, produce carbon fixation products and building material raw materials, realize the "exhaustive" and high-value utilization of steel slag.

[0005] At present, there are many technologies related to steel slag treatment and resource utilization, but they all have the following problems: 1) Low metal recovery rate: The existing magnetic separation process mostly uses single-stage magnetic separation or simple crushing and screening, and the capture rate of micro-fine metal particles is less than 60%, resulting in a large amount of metal remaining in the tailings, causing resource waste.

[0006] 2) Limited utilization of tailings: The content of free calcium oxide and magnesium oxide in the tailings is high, and direct use in building materials can easily cause volume expansion and cracking, and the existing stabilization technology (such as carbonization and heat soaking) has high cost and long cycle.

[0007] 3) Dispersed process flow: Most existing technologies only target a single link (such as desulfurization, carbon fixation or cement production), and do not form a full-process synergy, resulting in low energy and material recycling rate. SUMMARY

[0008] In order to solve the above technical problems, the purpose of the present application is to provide a steel slag full-quantitative treatment method and admixture based on step-by-step separation and high-value utilization. The method integrates multiple technologies such as magnetic separation, crushing, grinding, classification, separation, desulfurization, carbon sequestration, and building material utilization, forming a complete and efficient steel slag treatment and resource utilization industrial chain, and ultimately realizing zero discharge and high-value utilization of steel slag.

[0009] According to one aspect of the present application, a steel slag full-quantitative treatment method based on step-by-step separation and high-value utilization is provided, comprising the following steps: The steel slag is subjected to first-stage treatment to obtain steel slag powder, wherein the first-stage treatment includes iron removal treatment; The steel slag powder is subjected to second-stage treatment to obtain steel slag powder I and steel slag powder II meeting a preset particle size, the steel slag powder II is divided into two parts, steel slag powder II part I is used for flue gas desulfurization treatment to generate desulfurization slag, and steel slag powder II part II is used for ore pulp carbon sequestration treatment to generate carbon sequestration slag; the steel slag powder I is subjected to third-stage treatment to recover metal alloy materials therein to obtain final tailings; The desulfurization slag, carbon sequestration slag, and final tailings are used as core raw materials for preparing cement admixture, Wherein, the first-stage treatment, the second-stage treatment, and the third-stage treatment are carried out in sequence, and no chemical reagent needs to be introduced in each stage of treatment and desulfurization and carbon sequestration treatment, and there is no waste in the products obtained in each stage of treatment and desulfurization and carbon sequestration treatment.

[0010] Further, the first-stage treatment further includes crushing and screening and grinding, so that the steel slag is subjected to first-stage treatment to obtain steel slag powder, which includes: The steel slag sand obtained after iron removal treatment is subjected to crushing and screening treatment to obtain steel slag sand with a particle size controlled at 1-5 mm; The steel slag sand is ground to steel slag powder with a particle size of ≥45 mesh.

[0011] Further, the iron removal treatment is magnetic separation treatment, and the steel slag is subjected to magnetic separation treatment to separate out particle iron.

[0012] Further, the second-stage treatment includes particle size separation treatment, so that the steel slag powder is subjected to second-stage treatment to obtain steel slag powder I and steel slag powder II meeting a preset particle size, which includes: A preset particle size is configured with 250 mesh as a boundary, a particle size less than 250 mesh is set as the preset particle size, and the steel slag powder is subjected to particle size separation treatment based on the preset particle size by using a wind separation-reselection combined process to obtain steel slag powder I and steel slag powder II meeting the preset particle size.

[0013] Further, the third-stage treatment includes dry magnetic separation and wet magnetic separation, so that the steel slag powder I is subjected to third-stage treatment to recover metal alloy materials therein to obtain final tailings, which includes: The steel slag powder is first subjected to dry magnetic separation based on the correlation between magnetic force and weight to separate the first-stage metal alloy material. The tailings after dry magnetic separation are then subjected to wet magnetic separation to separate the second-stage metal alloy material and the final tailings. The first-stage metal alloy material and the second-stage metal alloy material belong to the metal alloy material.

[0014] Furthermore, the steel slag powder that meets the preset particle size is divided into two parts. Part one of the steel slag powder is used as a desulfurizing agent for flue gas desulfurization treatment, and reacts with SO2 in the flue gas to generate desulfurization slag. Part two of the steel slag powder is used for slurry carbon fixation treatment, and reacts with CO2 in the slurry system to generate carbon fixation slag.

[0015] The method for the comprehensive treatment of steel slag based on tiered separation and high-value utilization specifically includes the following steps: (1) Magnetic separation to remove iron: using a magnetic separator to separate granular iron from the raw material ironmaking slag; (2) Crushing and screening: The steel slag after iron removal in step (1) is crushed by a cone crusher to obtain steel slag sand with a particle size of 1-5mm; (3) Grinding: The steel slag sand obtained in step (2) is ground by a vertical mill to obtain steel slag powder with a particle size distribution of not less than 45 mesh; (4) Particle size separation: The steel slag powder obtained in step (3) is separated by a combined air separation-gravity separation process to separate two particle sizes of steel slag powder: steel slag powder one (fine) and steel slag powder two (coarse). (5) Desulfurization and carbon fixation treatment: The steel slag powder below 250 mesh obtained in step (4) is divided into two parts: the first part is used for flue gas desulfurization, which reacts with SO2 in the flue gas to generate desulfurization slag; the second part is used for slurry carbon fixation, which reacts with CO2 in the slurry system to generate carbon fixation slag. (6) Magnetic separation to recover metal: The steel slag powder of 250 mesh or finer obtained in step (4) is first subjected to dry magnetic separation to separate the first-grade metal alloy material; the tailings after dry magnetic separation are then subjected to wet magnetic separation to separate the second-grade metal alloy material and the final tailings, and the high-grade and low-grade metal alloy materials are recovered step by step. (7) Preparation of cement admixtures: The desulfurization slag, carbonization slag, final tailings obtained in step (5), stainless steel slag powder, stainless steel slag blocks, slag, cement clinker, limestone, mineral powder, grinding aid, and reinforcing agent obtained in step (6) are mixed in the following mass ratios to prepare general-purpose cement admixtures. The three by-products generated by this process—final tailings after magnetic separation, desulfurization slag generated from flue gas desulfurization, and carbonization slag generated from mineral slurry carbonization—are creatively used as core raw materials and compounded with other materials. The final tailings, desulfurization slag, carbonization slag, stainless steel slag powder, stainless steel slag blocks, slag, cement clinker, limestone, mineral powder, and a small amount of grinding aid and reinforcing agent are mixed in a specific and optimized mass ratio to prepare general-purpose cement admixtures of different grades such as PO42.5, PC42.5R, PC42.5, or M32.5 that can be used directly. This formula fully utilizes the potential hydraulic activity of the final tailings, the coagulation regulation effect of the desulfurization slag, the stabilization effect of the carbon-fixing slag, the micro-aggregate effect of the stainless steel slag, and the pozzolanic activity of the slag, achieving complementary performance and synergistic effect.

[0016] The slag mentioned in this invention is blast furnace slag produced during the iron and steel smelting process; the stainless steel slag powder and stainless steel slag blocks are powdery and lumpy materials obtained by processing waste slag produced during the stainless steel smelting process; the mineral powder is granulated blast furnace slag powder conforming to the GB / T18046 standard.

[0017] This method involves sequentially subjecting steel slag to magnetic separation for iron removal, crushing, and grinding to obtain steel slag powder. Air and gravity separation separates the slag into two particle sizes: below 250 mesh and above. The steel slag powder below 250 mesh is used for flue gas desulfurization and slurry carbon fixation, generating desulfurization slag and carbon fixation slag, respectively. The steel slag powder above 250 mesh undergoes multi-stage magnetic separation to recover metallic alloys and obtain final tailings. Finally, the final tailings, desulfurization slag, and carbon fixation slag are combined with other auxiliary materials in a specific ratio to prepare a general-purpose cement admixture. This invention achieves efficient recovery of iron metal from steel slag and full utilization of tailings resources, with a compact process flow and no secondary pollution.

[0018] According to another aspect of the present invention, a cement admixture is provided, which uses the desulfurization slag, carbonization slag, and final tailings obtained by any of the above methods as core raw materials.

[0019] Furthermore, the cement admixture, by weight, comprises 2-4 parts desulfurization slag, 2-4 parts carbon-fixing slag, and 10-30 parts final tailings. The raw materials also include: 26-66 parts cement clinker, 3-25 parts slag, 3-4 parts limestone, 3-5 parts stainless steel slag powder, 3-5 parts stainless steel slag blocks, 14-17 parts mineral powder, 0.05-0.07 parts liquid grinding aid, and 0.4-0.6 parts solid reinforcing agent.

[0020] Furthermore, the cement admixture is used to prepare any grade of cement, such as PO42.5, PC42.5R, PC42.5, or M32.5.

[0021] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention is a comprehensive steel slag treatment method based on tiered separation and high-value utilization. The entire process requires no chemical reagents, is environmentally friendly, and offers significant economic benefits. The final products are high-value metal raw materials and qualified cement, truly achieving complete utilization and zero emissions of steel slag.

[0022] 2. This invention creatively develops an optimized cement formula using byproducts from the entire steel slag treatment process (final tailings, desulfurization slag, and carbonization slag) as the main raw materials. This formula not only achieves large-scale disposal of solid waste, but also, through the synergistic effect of its components, produces cement whose performance fully meets or even exceeds the national standard (GB 175-2007), achieving a unity of "turning waste into treasure" and "high-value utilization." The final tailings, desulfurization slag, and carbonization slag are all used to prepare cement admixtures, achieving zero discharge of solid waste and full-scale resource utilization. This formula system is flexible; by adjusting the proportions of the final tailings, clinker, and slag, it can stably produce cement products of multiple grades, exhibiting strong market adaptability.

[0023] 3. This invention achieves the tiered processing and precise utilization of steel slag through a coupled process of "crushing-grinding-grading-sorting-utilization", which is compact and efficient.

[0024] 4. Through the combined air-gravity separation, efficient particle size separation of steel slag powder was achieved, laying the foundation for differentiated high-value utilization of steel slag of different particle sizes.

[0025] 5. Steel slag of suitable particle size is used for flue gas desulfurization and slurry carbon fixation, which not only reduces the cost of desulfurization and carbon fixation, but also achieves efficient utilization of steel slag. The generated desulfurization slag and carbon fixation slag have high purity, good quality and strong stability.

[0026] 6. A combined process of "particle size classification - dry magnetic separation - wet magnetic separation" is adopted for deep resource utilization of steel slag. First, the steel slag powder is classified into 250 meshes through air classification and gravity separation, which enriches the finer particles rich in metallic iron (steel slag powder one), creating conditions for subsequent high-efficiency magnetic separation. Then, dry magnetic separation is used to efficiently recover the stronger magnetic and higher-grade metal particles (first-stage metal alloy material); then, wet magnetic separation is used on the remaining tailings to effectively disperse the material in a liquid medium, reducing the inclusion and interference between particles, thereby capturing the fine, weakly magnetic metal particles that are difficult to recover by dry separation (second-stage metal alloy material). This tiered and coupled separation process based on material characteristics significantly improves the total recovery rate of metallic iron (≥92%), an effect that cannot be achieved by simply adding up a single magnetic separation process. Attached Figure Description

[0027] Figure 1 This is the X-ray diffraction (XRD) pattern of the steel slag raw material processed in this invention.

[0028] Figure 2 This is a process flow diagram of Embodiment 1 of the present invention. Detailed Implementation

[0029] To better understand the technical solution of the present invention, the present invention will be further described below in conjunction with specific embodiments and accompanying drawings.

[0030] Figure 1 This is the X-ray diffraction (XRD) pattern of the steel slag raw material processed in this application. As shown in the figure, the main crystalline phases of the steel slag are forsterite (Mg2(SiO4)) and ferromagnesian olivine solid solution ((Fe, Mg)2SiO4). This mineral composition characteristic explains the feasibility of the process of this invention from a mechanistic perspective. 1. Calcium and magnesium richness: The presence of olivine phase indicates that steel slag is rich in alkaline oxides such as CaO and MgO, which gives it the potential to be used for flue gas desulfurization, slurry carbon fixation and building material production. This provides the necessary chemical basis for its use as a desulfurizing agent and carbon fixation agent, and it can react efficiently with SO2 and CO2.

[0031] 2. Silicate structure: Its main phase is silicate, which has good potential hydraulic activity or micro-aggregate effect. This is the inherent reason why it can be used as a core component of cement admixture to achieve complementary performance and synergistic effect.

[0032] Therefore, based on this phase characteristic of steel slag, this invention designs a highly compatible "cascade separation-directional conversion" resource utilization path.

[0033] Example 1 The comprehensive steel slag treatment method based on cascade separation and high-value utilization described in this embodiment refers to... Figure 2 Specifically, it includes the following steps: (1) Magnetic separation to remove iron: using a magnetic separator to separate granular iron from the raw material ironmaking slag; (2) Crushing and screening: The steel slag after iron removal in step (1) is crushed by a cone crusher to obtain steel slag sand with a particle size of 1-5mm; (3) Grinding: The steel slag sand obtained in step (2) is ground by a vertical mill to obtain steel slag powder with a particle size distribution of not less than 45 mesh; (4) Particle size separation: The steel slag powder obtained in step (3) is separated by a combined air separation-gravity separation process to separate two particle sizes of steel slag powder: steel slag powder one (fine) and steel slag powder two (coarse). (5) Desulfurization and carbon fixation treatment: The steel slag powder below 250 mesh obtained in step (4) is divided into two parts: the first part is used for flue gas desulfurization, which reacts with SO2 in the flue gas to generate desulfurization slag; the second part is used for slurry carbon fixation, which reacts with CO2 in the slurry system to generate carbon fixation slag. (6) Magnetic separation to recover metal: The steel slag powder of 250 mesh or finer obtained in step (4) is first subjected to dry magnetic separation to separate the first-level metal alloy material; the tailings after dry magnetic separation are then subjected to wet magnetic separation to separate the second-level metal alloy material and the final tailings. (7) Preparation of cement admixture: The desulfurization slag, carbon fixation slag and final tailings obtained in step (5) are used as core raw materials and mixed with stainless steel slag powder, stainless steel slag blocks, slag, cement clinker, limestone, mineral powder and grinding aid and reinforcing agent in the following mass ratio to prepare general cement admixture.

[0034] According to another aspect of the present invention, a cement admixture is provided, which uses the desulfurization slag, carbonization slag, and final tailings obtained by any of the above methods as core raw materials.

[0035] Furthermore, the cement admixture, by weight, comprises 2-4 parts desulfurization slag, 2-4 parts carbon-fixing slag, and 10-30 parts final tailings. The raw materials also include: 26-66 parts cement clinker, 3-25 parts slag, 3-4 parts limestone, 3-5 parts stainless steel slag powder, 3-5 parts stainless steel slag blocks, 14-17 parts mineral powder, 0.05-0.07 parts liquid grinding aid, and 0.4-0.6 parts solid reinforcing agent.

[0036] The cement admixture is used to prepare any grade of cement, such as PO42.5, PC42.5R, PC42.5, or M32.5.

[0037] Implementation Case 2 The features that are the same as those in Example 1 will not be repeated here. The features that differ from those in Example 1 are as follows: Processing 50kg of converter steel slag (1) Magnetic separation to remove iron: about 5.5 kg of granular iron was recovered.

[0038] (2) Crushing and screening: about 42.5 kg of steel slag sand was obtained.

[0039] (3) Grinding: about 41 kg of steel slag powder was obtained (specific surface area of ​​about 450 m² / kg).

[0040] (4) Particle size sorting: about 17.5 kg of steel slag powder with a mesh size of less than 250 and about 23.5 kg of steel slag powder with a mesh size of more than 250 were obtained.

[0041] (5) Desulfurization and carbon fixation treatment: 17.5 kg of steel slag powder is divided into two parts: about 8.75 kg is used for flue gas desulfurization, generating about 8.2 kg of desulfurization slag; about 8.75 kg is used for slurry carbon fixation, generating about 8.3 kg of carbon fixation slag.

[0042] (6) Magnetic separation to recover metal: Dry magnetic separation yields about 3 kg of first-grade alloy material (iron grade 88%); wet magnetic separation yields about 1 kg of second-grade alloy material (iron grade 75%); and the final tailings are about 19.5 kg.

[0043] (7) Preparation of cement admixture: 19.5 kg of final tailings, 8.2 kg of desulfurization slag, and 8.3 kg of carbonization slag are mixed with other auxiliary materials by weight in the following proportions to prepare PC42.5 cement admixture: cement clinker: 58 parts, slag: 3 parts, tailings: 21.4 parts, desulfurization slag: 3 parts, carbonization slag: 3 parts, limestone: 4 parts, stainless steel slag powder: 4 parts, stainless steel slag blocks: 4 parts, mineral powder: 17 parts, liquid grinding aid: 0.06 parts, solid reinforcing agent: 0.5 parts.

[0044] Example 3 The features that are the same as those in Example 1 will not be repeated here. The features that differ from those in Example 1 are as follows: Processing 800kg of electric furnace steel slag (1) Magnetic separation to remove iron: about 160 kg of granular iron was recovered.

[0045] (2) Crushing and screening: about 600 kg of steel slag sand was obtained.

[0046] (3) Grinding: about 580 kg of steel slag powder was obtained (specific surface area of ​​about 500 m² / kg).

[0047] (4) Particle size sorting: about 220 kg of steel slag powder with a mesh size of less than 250 mesh and about 360 kg of steel slag powder with a mesh size of more than 250 mesh were obtained.

[0048] (5) Desulfurization and carbon fixation treatment: 220kg of steel slag powder is divided into two parts: about 110kg is used for flue gas desulfurization, generating about 105kg of desulfurization slag; about 110kg is used for slurry carbon fixation, generating about 106kg of carbon fixation slag.

[0049] (6) Magnetic separation to recover metal: Dry magnetic separation yields about 70 kg of first-grade alloy material (90% iron content); wet magnetic separation yields about 30 kg of second-grade alloy material (78% iron content); and the final tailings yield about 260 kg.

[0050] (7) Preparation of cement admixture: 260 kg of final tailings, 105 kg of desulfurization slag, and 106 kg of carbonization slag are mixed with other auxiliary materials in the following proportions by weight to prepare PO42.5 cement admixture: cement clinker: 66 parts, slag: 15 parts, tailings: 10 parts, desulfurization slag: 4 parts, carbonization slag: 4 parts, limestone: 3 parts, stainless steel slag powder: 3 parts, stainless steel slag blocks: 3 parts, mineral powder: 14 parts, liquid grinding aid: 0.05 parts, solid reinforcing agent: 0.4 parts.

[0051] Example 4 The features that are the same as those in Example 1 will not be repeated here. The features that differ from those in Example 1 are as follows: Processing 10 tons of converter steel slag (1) Magnetic separation to remove iron: about 1.1 tons of granular iron were recovered.

[0052] (2) Crushing and screening: about 8.5 tons of steel slag sand were obtained.

[0053] (3) Grinding: about 8.2 tons of steel slag powder (specific surface area about 450 m² / kg) were obtained.

[0054] (4) Particle size sorting: about 3.5 tons of steel slag powder below 250 mesh and about 4.7 tons of steel slag powder above 250 mesh were obtained.

[0055] (5) Desulfurization and carbon fixation treatment: 3.5 tons of steel slag powder is divided into two parts: about 1.75 tons are used for flue gas desulfurization, generating about 1.65 tons of desulfurization slag; about 1.75 tons are used for slurry carbon fixation, generating about 1.68 tons of carbon fixation slag.

[0056] (6) Magnetic separation to recover metal: Dry magnetic separation yields about 0.6 tons of first-grade alloy material (iron grade 88%); wet magnetic separation yields about 0.2 tons of second-grade alloy material (iron grade 75%); and the final tailings are about 3.9 tons.

[0057] (7) Preparation of cement admixture: 3.9 tons of final tailings, 1.65 tons of desulfurization slag, and 1.68 tons of carbon-fixing slag, along with other auxiliary materials, are mixed by weight in the following proportions to prepare M32.5 cement admixture: cement clinker: 26 parts, tailings: 30 parts, slag: 25 parts, desulfurization slag: 3 parts, carbon-fixing slag: 3 parts, limestone: 4 parts, stainless steel slag powder: 5 parts, stainless steel slag blocks: 5 parts, mineral powder: 15 parts, liquid grinding aid: 0.07 parts, solid reinforcing agent: 0.6 parts.

[0058] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to the technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, the above-described features have similar functions to (but are not limited to) those disclosed in this application.

Claims

1. A steel slag full-quantitative treatment method based on step separation and high-value utilization, characterized in that, The method comprises the following steps: The steel slag is processed by a first stage to obtain steel slag powder, wherein the first stage processing comprises iron removal processing; The steel slag powder is processed by a second stage to obtain steel slag powder I and steel slag powder II meeting a preset particle size, the steel slag powder II is divided into two parts, steel slag powder II part I is used for flue gas desulfurization processing to generate desulfurization slag, and steel slag powder II part II is used for ore pulp carbon sequestration processing to generate carbon sequestration slag; the steel slag powder I is processed by a third stage to recover metal alloy materials in the steel slag powder I to obtain final tailings; The desulfurization slag, the carbon sequestration slag, and the final tailings are used as core raw materials for preparing cement admixture, The first stage processing, the second stage processing, and the third stage processing are sequentially performed, and no chemical reagent needs to be introduced in the iron removal processing, the carbon sequestration processing, and each stage processing, and there is no waste in the products obtained by the iron removal processing, the carbon sequestration processing, and each stage processing.

2. The steel slag total quantization treatment method based on step separation and high-value utilization according to claim 1, characterized by, The first stage processing further comprises crushing and screening, and grinding, so that the steel slag is processed by the first stage to obtain the steel slag powder, which comprises the following steps: The steel slag sand is crushed and screened to obtain steel slag sand with a particle size of 1-5 mm; The steel slag sand is ground to obtain steel slag powder with a particle size of not less than 45 mesh. The iron removal processing is magnetic separation processing, and the steel slag is subjected to the magnetic separation processing to separate out the particle iron.

3. The steel slag total quantization treatment method based on step separation and high-value utilization according to claim 2, characterized by, The second stage processing comprises particle size sorting processing, so that the steel slag powder is processed by the second stage to obtain the steel slag powder I and the steel slag powder II meeting the preset particle size, which comprises the following steps:

4. The steel slag total quantization treatment method based on step separation and high value utilization according to any one of claims 1 to 3, characterized by, The preset particle size is set with 250 mesh as a boundary, the particle size less than 250 mesh is set as the preset particle size, and the steel slag powder is subjected to the particle size sorting processing based on the preset particle size by using a combined process of air separation and gravity separation to obtain the steel slag powder I and the steel slag powder II meeting the preset particle size. The third stage processing comprises dry magnetic separation and wet magnetic separation, so that the steel slag powder I is processed by the third stage to recover the metal alloy materials in the steel slag powder I to obtain the final tailings, which comprises the following steps: The steel slag powder I is subjected to the dry magnetic separation processing based on the correlation between the magnetic force and the weight to separate out the first-stage metal alloy materials; 5. The steel slag total quantization treatment method based on step separation and high-value utilization according to claim 4, characterized by, The tailings after the dry magnetic separation are subjected to the wet magnetic separation processing to separate out the second-stage metal alloy materials and the final tailings, and the first-stage metal alloy materials and the second-stage metal alloy materials belong to the metal alloy materials.

6. The steel slag full-quantitative processing method based on stage separation and high-value utilization according to claim 5, wherein the steel slag powder II meeting the preset particle size is divided into two parts, steel slag powder II part I is used as a desulfurizer for flue gas desulfurization processing to react with SO2 in the flue gas to generate desulfurization slag, and steel slag powder II part II is used for ore pulp carbon sequestration processing to react with CO2 in an ore pulp system to generate carbon sequestration slag. The desulfurization slag, the carbon sequestration slag, and the final tailings obtained by the method according to any one of claims 1-6 are used as core raw materials. In terms of weight parts, the desulfurization slag is 2-4 parts, the carbon sequestration slag is 2-4 parts, and the final tailings are 10-30 parts, and the raw materials further comprise cement clinker 26-66 parts, slag 3-25 parts, limestone 3-4 parts, stainless steel slag powder 3-5 parts, stainless steel slag block 3-5 parts, mineral powder 14-17 parts, liquid grinding aid 0.05-0.07 parts, and solid reinforcing agent 0.4-0.6 parts. ​ ​ 7. A cement admixture characterized by, ​ 8. The cement admixture of claim 7, wherein ​ 9. The cement admixture of claim 8, characterized by For the production of cement of any grade PO 42.5, PC 42.5 R, PC 42.5, M 32.5.

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