A method for controlling the temperature of siderite produced by waste heat treatment of steel slag, the products obtained and their applications

Abstract

This invention discloses a production method, the resulting product, and its application in the field of iron and steel metallurgical technology, which utilizes the waste heat from steel slag for temperature control. The invention calculates the amount of siderite that can be added based on the temperature and mass of the steel slag, then places the siderite on top of the liquid steel slag. It calculates the corresponding slag temperature during slag cooling and adds coke tailings at 1210℃ and 600℃, with the amount of coke added being 5% of the siderite mass. After crushing and cooling, the steel slag is magnetically separated to obtain iron ore. The remaining non-magnetic steel slag is the slagging agent, with calcium ferrite as its effective component. This invention utilizes the absorption of waste heat from steel slag by siderite, combined with temperature control, to efficiently recover waste heat from steel slag and process siderite at low cost. The resulting products are iron ore and a slagging agent that can be directly fed into the furnace, bringing significant economic value to enterprises and making a significant contribution to energy conservation and emission reduction in the steel industry.

Description

Technical Field

[0001] This invention belongs to the field of iron and steel metallurgy technology, and more specifically, relates to a production method for controlling the temperature of siderite treated by waste heat from steel slag, the product obtained, and its application. Background Technology

[0002] Steel slag is a solid waste generated during the steelmaking process, with a large output, exceeding 100 million tons in 2022 alone. The slag discharge temperature is high, between 1400-1600℃, and the heat released by a ton of slag after complete cooling is equivalent to the heat generated by the complete combustion of 50-60 kg of standard coal. Currently, the mainstream processes used by steel companies include high-temperature hot pouring of steel slag, air quenching (represented by Maanshan Iron & Steel), drum processing (represented by Baosteel), and pool-type hot quenching and pressurized hot quenching processes led by the China Metallurgical Construction Research Institute. These steel slag treatment processes focus on the recycling of slag steel and tailings, but the problem of recovering waste heat from steel slag has not been effectively solved. Existing technologies can only recover heat in the temperature range below 400℃, with a recovery rate of less than 30%. If the waste heat from steel slag could be effectively recovered, it could save my country 5-6 million tons of standard coal annually.

[0003] Siderite is an important iron-bearing resource with abundant reserves in my country, with proven reserves reaching 1.834 billion tons. It is widely used in the steel industry. The main component of siderite is FeCO3, which means that more heat is required for the decomposition of FeCO3 when utilizing siderite. In addition, siderite is often of lower grade, resulting in lower utilization value compared to other iron ores.

[0004] The existing steel slag waste heat recovery and siderite utilization have the following problems: 1) Steel slag heat energy recovery is insufficient, especially heat above 400℃ can hardly be recovered; 2) Steel slag cannot be reused after treatment, and its stockpiling and landfilling pollute the environment; 3) Siderite roasting requires a large amount of valuable energy.

[0005] A search revealed that patent CN107604157A discloses a method for preparing iron-carbon composite agglomerates for blast furnaces using hot converter slag, comprising: 1) batching calculation; 2) mixing and briquetting; 3) preheating treatment; 4) first spreading; 5) casting; 6) second spreading; 7) sintering; 8) nitrogen cooling; and 9) crushing and screening. This invention utilizes the residual heat of high-temperature hot converter slag to heat the iron-carbon composite agglomerates, causing a reduction reaction to generate metallic iron. The calcium and magnesium resources of the converter slag are used as binder phases to bind carbon, metallic iron, and their oxides to prepare iron-carbon composite agglomerates with a certain alkalinity. Patent CN104694679A discloses a method for recovering and utilizing heat from steel slag. This invention utilizes carbonate minerals to absorb heat from liquid steel slag. The carbonate minerals are one or more of dolomite, limestone, magnesite, and siderite. The absorption of heat from liquid steel slag by carbonate minerals can be achieved through mixing or heat transfer. This invention utilizes the decomposition of carbonates to absorb the waste heat of steel slag, and the heat in the steel slag temperature range above 400℃ can be efficiently utilized. However, the above technical solution lacks precise process control, resulting in the inability to effectively transform materials into high-value-added products, causing a certain degree of waste, and insufficient heat recovery. Summary of the Invention

[0006] 1. The problem to be solved

[0007] To address the problems of insufficient heat recovery and low added value of processed products due to imprecise control of existing steel slag heat recovery processes, this invention provides a production method for controlling the temperature of steel slag waste heat to process siderite, the resulting products, and their applications. The method utilizes high-temperature steel slag generated during converter smelting to process siderite, and the processed products are iron ore that can be directly added to the converter and calcium ferrite auxiliary material that helps to quickly slag in the early stage of converter smelting.

[0008] 2. Technical Solution

[0009] To solve the above problems, the technical solution adopted by the present invention is as follows:

[0010] This invention provides a method for producing siderite by controlling the temperature of waste heat from steel slag, comprising the following steps:

[0011] S1: Mixing: Pour the liquid steel slag into a slag basin. Calculate the required mass of siderite to be added based on the temperature and mass of the steel slag. Then, place an appropriate amount of siderite on top of the liquid steel slag. The mass of siderite to be added can be obtained through heat balance calculations, and the specific calculation formula is as follows:

[0012]

[0013] In the formula: To the maximum mass of siderite that can be added, For the specific heat capacity of steel slag, For the quality of steel slag, For the temperature of steel slag, The latent heat of phase transformation of steel slag, The specific heat capacity of the ore. This represents the proportion of FeCO3 in siderite. The latent heat of decomposition of FeCO3, This refers to the calorific value of coke.

[0014] Preferably, the siderite mass calculated by the above formula is the maximum siderite addition amount. In actual production, the addition amount can be less than or equal to this mass to ensure that the siderite can react fully.

[0015] Preferably, the siderite has a diameter of less than 30 mm and is crushed using a crusher; the crushing of the siderite is not limited to a specific crushing machine; the diameter of the crushed siderite needs to be less than 30 mm to allow the siderite particles to react fully within a limited time; there is no limit to the minimum particle size, as small particle size and powder are beneficial for rapid reaction with steel slag to form calcium ferrite.

[0016] S2: Reaction: Calculate the corresponding time of slag temperature during steel slag cooling, and add coke at 1210℃ and 600℃. Preferably, the amount of coke added is 4%-7% of the mass of siderite, and more preferably 5%; the coke is coke tailings.

[0017] Adding coke at 1210℃ and 600℃ is to control the temperature and maintain it at that temperature for a period of time, providing favorable conditions for the corresponding reaction. 1210℃ is the temperature corresponding to the maximum reaction rate of calcium ferrite, and 600℃ is the magnetization temperature of the siderite decomposition products. Holding the temperature for a period of time helps the iron ore components to transform into Fe3O4, which facilitates the subsequent magnetic separation work. The coke tailings are coke crushed material whose particle size does not meet the requirements for blast furnace feeding and has low utilization value.

[0018] Calculating the corresponding times for slag temperature during slag cooling is to obtain the time points when the slag temperature is 1210℃ and 600℃, thereby achieving slag temperature control. The specific calculation formula is as follows:

[0019]

[0020] In the formula: For the specific heat capacity of steel slag, For the quality of steel slag, For the temperature of steel slag, For the target temperature, The latent heat of phase transformation of steel slag, The specific heat capacity of the ore. To improve the quality of siderite, The thermal diffusivity of steel slag is... The surface area of ​​the molten steel slag. Let be the blackbody radiation constant. This refers to the density of steel slag.

[0021] Preferably, the amount of coke added is 5% of the mass of siderite. The addition ratio is determined by experiments. Experiments show that when the amount of coke added is 5% of the mass of siderite, the steel slag can be kept at 1210℃ for 10 minutes to meet the time requirement for complete conversion of calcium ferrite; the steel slag can be kept at 600℃ for 16 minutes to meet the time requirement for complete magnetization of the decomposition products of siderite.

[0022] After the steel slag is cooled and crushed through the above steps, iron ore is obtained by magnetic separation. The remaining non-magnetic steel slag is the slag-forming agent with calcium ferrite as its effective component.

[0023] The magnetically separated iron ore mainly consists of Fe3O4 and Fe2O3, which can replace iron-containing raw materials added in converter production, such as sinter and lump ore. The non-magnetic steel slag's effective component is calcium ferrite, which can replace slagging agents added in converter production. It should be noted that the mass of this non-magnetic steel slag added in a single converter smelting cycle should not exceed 500 kg; otherwise, it will impose an additional dephosphorization burden on the converter steelmaking process.

[0024] The present invention discloses a method for producing siderite using waste heat from steel slag. This method utilizes the heat energy contained in the steel slag to roast the siderite, achieving the decomposition of FeCO3. After crushing and magnetic separation, the resulting iron ore can be directly added to the converter. Furthermore, by adding coke tailings to control the cooling rate during roasting, favorable conditions are provided for the reaction between the siderite and CaO in the steel slag, promoting the formation of calcium ferrite. After crushing, this calcium ferrite is added to the converter as a slagging agent, aiding in rapid slagging in the early stages of converter operation. By utilizing the difficult-to-recover waste heat from steel slag and the unusable siderite, the method obtains both iron ore and a slagging agent, reducing the company's auxiliary material procurement and steel slag treatment costs, and significantly lowering production costs.

[0025] 3. Beneficial effects

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0027] (1) The present invention provides a method for producing siderite by controlling the temperature of waste heat from steel slag. By using high-temperature steel slag produced by converter smelting and precisely controlling the amount and time of siderite addition, the product obtained is iron ore and calcium ferrite slag agent that can be directly added to converter smelting, thereby increasing the product yield.

[0028] (2) The present invention provides a method for producing siderite by controlling the temperature of steel slag waste heat treatment. It utilizes the waste heat of steel slag, which is difficult to recover, to treat siderite with high beneficiation costs. The resulting product is iron ore and calcium ferrite slag agent that can be directly added to converter smelting. This brings great economic value to enterprises. Moreover, the processing flow of the present invention is simple, does not require specific equipment, and is highly adaptable to enterprises. After treatment, the steel slag is partially recycled within the enterprise, saving natural resources and reducing the amount of metallurgical solid waste leaving the factory area.

[0029] (3) The present invention provides a method for producing siderite by controlling the temperature of steel slag waste heat. It does not require water quenching or air quenching of steel slag, so the whole process is safe, stable and controllable, and does not generate wastewater or dust to pollute the environment.

[0030] (4) The present invention provides a method for producing siderite by controlling the temperature of steel slag waste heat. Compared with conventional siderite beneficiation methods, it significantly reduces the processing cost and does not require the consumption of valuable energy. The method does not limit the minimum particle size of siderite and can make full use of siderite resources. Attached Figure Description

[0031] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. However, it should be understood that these drawings are designed for illustrative purposes only and are not intended to limit the scope of the present invention. Furthermore, unless specifically indicated, these drawings are intended only to conceptually illustrate the structural construction described herein and are not necessarily drawn to scale.

[0032] Figure 1 This is a flowchart illustrating the steps of the present invention;

[0033] Figure 2 This is a process flow diagram of the present invention. Detailed Implementation

[0034] The following detailed description of exemplary embodiments of the invention is taken with reference to the accompanying drawings, which form part of the description and illustrate exemplary embodiments in which the invention may be practiced. While these exemplary embodiments have been described in sufficient detail to enable those skilled in the art to practice the invention, it should be understood that other embodiments may be implemented and various changes may be made to the invention without departing from the spirit and scope thereof. The more detailed description of embodiments of the invention below is not intended to limit the scope of the claimed invention, but is merely illustrative and not restrictive of the description of the features and characteristics of the invention, to suggest the best mode for carrying out the invention, and is sufficient to enable those skilled in the art to practice the invention. Therefore, the scope of the invention is defined only by the appended claims.

[0035] Example 1

[0036] The steel slag used in Example 1 was randomly selected from a heat of steel produced by a steel plant. Its active ingredient was CaO, accounting for 42% by mass. The slag temperature was 1540℃, and the slag mass was 5400 kg. The siderite used was purchased from Chizhou Zhongyin Mining Co., Ltd., with an FeCO3 content of 68.4%. The coke tailings were coke waste that did not meet the particle size requirements for blast furnace coke, and its active ingredient was C, accounting for 95% by mass.

[0037] Example 1 describes a method for producing siderite by controlling the temperature of waste heat from steel slag, comprising the following steps:

[0038] Step S1, Crushing: Use a jaw crusher (model PE400*600) to crush the siderite. After crushing, screen the siderite. The target diameter should be less than 30mm. Siderite particles larger than 30mm are returned to the crusher for re-crushing. Repeat this process until all crushed products meet the requirements.

[0039] Step S2, Mixing: Pour the liquid steel slag into the slag basin all at once. While pouring the steel slag, calculate the mass of siderite to be added based on the temperature and mass of the steel slag. The specific calculation process is as follows:

[0040]

[0041] In the formula: To the maximum mass of siderite that can be added, For the specific heat capacity of steel slag, For the quality of steel slag, For the temperature of steel slag, The latent heat of phase transformation of steel slag, Specific heat capacity of the ore; This represents the proportion of FeCO3 in siderite. The latent heat of decomposition of FeCO3, This refers to the calorific value of coke. Specific values ​​are shown in Table 1-1. The maximum mass of siderite that can be added is calculated from this. It weighs 2350 kg.

[0042] Table 1-1 Parameters for calculating the mass of siderite in Example 1

[0043]

[0044] After the steel slag is poured out, 2350 kg of siderite is added to the slag basin. Siderite has a higher density than steel slag, and due to the surface tension and viscosity of the steel slag, the siderite will slowly settle to the bottom of the steel slag, thus optimizing the heat transfer between the siderite and the steel slag.

[0045] Step S3, Reaction: Calculate the corresponding time points when the steel slag cools. Add coke tailings at 1210℃ and 600℃, with the amount of coke added being 5% of the mass of siderite. Using the time when the siderite addition ends as the zero point, calculate the time points corresponding to the steel slag temperatures of 1210℃ and 600℃. The specific calculation process is as follows:

[0046]

[0047] In the formula: t is the time point corresponding to the target temperature of the steel slag. For the specific heat capacity of steel slag, For the quality of steel slag, For the temperature of steel slag, For the target temperature, The latent heat of phase transformation of steel slag, The specific heat capacity of the ore. To improve the quality of siderite, The thermal diffusivity of steel slag is... The surface area of ​​the molten steel slag. Let be the blackbody radiation constant. This represents the density of the steel slag. Specific values ​​are shown in Table 1-2. The target temperature was calculated from this. When the target temperature is 1210 ℃, the corresponding time point t is 1024 s; target temperature At 600 ℃, the target temperature of the steel slag corresponds to time point t of 2130 s.

[0048] Table 1-2 Calculation formula parameters for slag temperature at corresponding time in Example 1

[0049]

[0050] The first batch of coke tailings was added 1024 seconds after the addition of siderite, with a mass of 5% of the added siderite mass, i.e., 117.5 kg. This allowed the steel slag to be kept at 1210℃ for 10 minutes, meeting the time requirement for complete conversion of calcium ferrite. The second batch of coke tailings was added 2130 seconds after the addition of siderite. Since the first batch of coke was exothermic, the steel slag was kept at 10 minutes. Therefore, the actual addition time of the second batch of coke tailings was 2730 seconds, and the added mass was 117.5 kg.

[0051] Step S4, Crushing and Cooling: After crushing and cooling, the steel slag is magnetically separated to obtain iron ore. The remaining non-magnetic steel slag is the slag-forming agent with calcium ferrite as its effective component.

[0052] The steel slag after complete cooling is crushed using a PE600*900 crusher. Since the decomposition of siderite produces a large amount of CO2, some of the CO2 remains in the steel slag, reducing its mechanical strength. Compared with conventional steel slag crushing, this invention reduces the energy consumption of steel slag crushing.

[0053] In this embodiment, because the company has particle size requirements for the raw materials and auxiliary materials fed into the converter, the crushed material needs to be screened for particle size, with a target diameter of 20-60mm. Subsequently, magnetic separation is performed using a drum magnetic separator, model HJ9322. The product obtained from the magnetic separation is iron ore, which can be directly added to the converter as an iron-containing raw material. The remaining non-magnetic steel slag contains calcium ferrite, which can be added to the converter as a slagging agent to promote rapid slagging in the early stages of the converter process. In this embodiment, the mass of iron ore obtained is 837kg, and the mass of calcium ferrite obtained is 1160kg.

[0054] Example 2

[0055] The steel slag used in Example 2 was randomly selected from a heat of steel produced by a steel plant. Its active ingredient was CaO, accounting for 39% by mass. The slag temperature was 1490℃, and the slag mass was 4800 kg. The siderite used was purchased from Chizhou Zhongyin Mining Co., Ltd., with an FeCO3 content of 70.4%. The coke tailings were coke waste that did not meet the particle size requirements for blast furnace coke, and its active ingredient was C, accounting for 95% by mass.

[0056] Step S1, Crushing: Use a jaw crusher (model PE400*600) to crush the siderite. After crushing, screen the siderite. The target diameter should be less than 30mm. Siderite particles larger than 30mm are returned to the crusher for re-crushing. Repeat this process until all crushed products meet the requirements.

[0057] Step S2, Mixing: Pour the liquid steel slag into the slag basin all at once. While pouring the steel slag, calculate the mass of siderite to be added based on the temperature and mass of the steel slag. The specific calculation process is as follows:

[0058]

[0059] In the formula: To the maximum mass of siderite that can be added, For the specific heat capacity of steel slag, For the quality of steel slag, For the temperature of steel slag, The latent heat of phase transformation of steel slag, The specific heat capacity of the ore. This represents the proportion of FeCO3 in siderite. The latent heat of decomposition of FeCO3, The calorific value of coke is given in Table 2-1. The maximum mass of siderite that can be added is calculated from this value. It weighs 1968 kg.

[0060] Table 2-1 Parameters for calculating the mass of siderite in Example 2

[0061]

[0062] After the steel slag was dumped, 1968 kg of siderite was added to the slag basin.

[0063] Step S3, Reaction: Taking the moment when the siderite addition ends as the zero point, calculate the time points corresponding to the steel slag temperatures of 1210℃ and 600℃. The specific calculation process is as follows:

[0064]

[0065] In the formula: t is the time point corresponding to the target temperature of the steel slag. For the specific heat capacity of steel slag, For the quality of steel slag, For the temperature of steel slag, For the target temperature, The latent heat of phase transformation of steel slag, The specific heat capacity of the ore. To improve the quality of siderite, The thermal diffusivity of steel slag is... The surface area of ​​the molten steel slag. Let be the blackbody radiation constant. This represents the density of the steel slag. Specific values ​​are shown in Table 2-2. The target temperature was calculated from this. When the target temperature of the steel slag is 1210 ℃, the corresponding time point t is 885 s; target temperature At 600 ℃, the target temperature of the steel slag corresponds to time point t, which is 1873 s.

[0066] Table 2-2 Calculation formula parameters for slag temperature at corresponding time in Example 2

[0067]

[0068] The first batch of coke tailings, weighing 98.4 kg, was added 885 s after the addition of siderite. This allowed the steel slag to be kept at 1210℃ for 10 min, meeting the time requirement for complete conversion of calcium ferrite. The second batch of coke tailings, weighing 98.4 kg, was added 2473 s after the addition of siderite.

[0069] Step S4, Crushing and Cooling: The completely cooled steel slag is crushed using a PE400*600 crusher. In this embodiment, because the company has particle size requirements for the raw materials entering the converter, particle size screening is required after crushing, with a target diameter of 25-60mm. Subsequently, magnetic separation is performed using a drum magnetic separator, model HJ9322. The product obtained from the magnetic separation is iron ore, which can be directly added to the converter as an iron-containing raw material. The remaining non-magnetic steel slag contains calcium ferrite, which can be added to the converter as a slagging agent to promote rapid slagging in the early stages of converter operation. In this embodiment, 774 kg of iron ore and 1040 kg of calcium ferrite were obtained.

[0070] Example 3

[0071] The steel slag used in Example 3 was randomly selected from a heat of steel produced by a steel plant. Its active ingredient was CaO, accounting for 43.4% by mass. The slag temperature was 1520℃, and the slag mass was 6350 kg. The siderite used was purchased from Chizhou Zhongyin Mining Co., Ltd., with an FeCO3 content of 66.7%. The coke tailings were coke waste that did not meet the particle size requirements for blast furnace coke, and its active ingredient was C, accounting for 92.6% by mass.

[0072] Step S1, Crushing: Use a jaw crusher (model PE400*600) to crush the siderite. After crushing, screen the siderite. The target diameter should be less than 30mm. Siderite particles larger than 30mm are returned to the crusher for re-crushing. Repeat this process until all crushed products meet the requirements.

[0073] Step S2, Mixing: Pour the liquid steel slag into the slag basin all at once. While pouring the steel slag, calculate the mass of siderite to be added based on the temperature and mass of the steel slag. The specific calculation process is as follows:

[0074]

[0075] In the formula: To the maximum mass of siderite that can be added, For the specific heat capacity of steel slag, For the quality of steel slag, For the temperature of steel slag, The latent heat of phase transformation of steel slag. The specific heat capacity of the ore. This represents the proportion of FeCO3 in siderite. The latent heat of decomposition of FeCO3, This refers to the calorific value of coke. Specific values ​​are shown in Table 3-1. The maximum mass of siderite that can be added is calculated from this. It weighs 2785 kg.

[0076] Table 3-1 Parameters for calculating the mass of siderite in Example 3

[0077]

[0078] After the steel slag has been dumped, add 2785 kg of siderite to the slag basin.

[0079] Step S3, Reaction: Taking the moment when the siderite addition ends as the zero point, calculate the time points corresponding to the steel slag temperatures of 1210℃ and 600℃. The specific calculation process is as follows:

[0080]

[0081] In the formula: t is the time point corresponding to the target temperature of the steel slag. For the specific heat capacity of steel slag, For the quality of steel slag, For the temperature of steel slag, For the target temperature, The latent heat of phase transformation of steel slag. The specific heat capacity of the ore. To improve the quality of siderite, The thermal diffusivity of steel slag is... The surface area of ​​the molten steel slag. Let be the blackbody radiation constant. This represents the density of the steel slag. Specific values ​​are shown in Table 3-2. The target temperature was calculated from this. When the target temperature is 1210 ℃, the corresponding time point t is 921 s; target temperature At 600 ℃, the target temperature of the steel slag corresponds to time point t, which is 1989 s.

[0082] Table 3-2 Calculation formula parameters for slag temperature at corresponding time in Example 3

[0083]

[0084] The first batch of coke tailings, weighing 189.25 kg, was added 921 s after the addition of siderite. This allowed the steel slag to be kept at 1210℃ for 10 min, meeting the time requirement for complete conversion of calcium ferrite. The second batch of coke tailings, weighing 189.25 kg, was added 2589 s after the addition of siderite.

[0085] Step S4, Crushing and Cooling: The completely cooled steel slag is crushed using a PE600*900 crusher. In this embodiment, because the company has particle size requirements for the raw materials entering the converter, particle size screening is required after crushing, with a target diameter of 30-65mm. Subsequently, magnetic separation is performed using a drum magnetic separator, model RCDB-8. The product obtained from the magnetic separation is iron ore, which can be directly added to the converter as an iron-containing raw material. The remaining non-magnetic steel slag contains calcium ferrite, which can be added to the converter as a slagging agent to promote rapid slagging in the early stages of the converter process. In this embodiment, the mass of iron ore obtained is 1260kg, and the mass of calcium ferrite obtained is 1648kg.

[0086] Comparative Example 1

[0087] A batch of steel slag was randomly selected within the enterprise. Half of the slag was processed using the enterprise's original process, while the other half was processed using this method. The overall processing costs were then compared.

[0088] The company's original steel slag treatment process was pressurized hot quenching, which included two steps: roller crushing and pressurized hot quenching. It used automated processing equipment that could recover the low-temperature heat energy of the steel slag at 500-100℃ through water heat exchange. The steel slag after processing was entrusted to a third-party company for further treatment.

[0089] The slag temperature for this heat was 1505℃, and the slag mass was 5840 kg. Therefore, the slag mass processed by the two methods was 2920 kg. A comparison of the overall processed slag composition is shown in the table below:

[0090] Table 4. Comprehensive Cost of Steel Slag Treatment

[0091]

[0092] This invention uses the waste heat from steel slag to treat siderite. Compared with the original process of the enterprise, the original comprehensive treatment cost was 79 yuan, while the comprehensive treatment cost of this invention is 96 yuan. This invention has achieved a revolutionary transformation from loss to profit in steel slag treatment, bringing huge economic value to the enterprise and realizing the full utilization and recycling of resources.

Claims

1. A production method of spheroidizing siderite by steel slag waste heat temperature control treatment, characterized by, The method comprises the following steps: S1: mixing: pouring liquid steel slag into a slag basin, calculating the maximum mass of siderite that can be added according to the temperature and mass of the steel slag, and then placing the siderite with a mass less than or equal to the maximum mass of siderite that can be added on the liquid steel slag; S2: reaction: calculating the time corresponding to the slag temperature when the steel slag is cooled, and adding coke when the temperature of the steel slag is 1210 DEG C and 600 DEG C; S3: crushing and cooling: after the steel slag is crushed and cooled, iron ore is obtained after magnetic separation, and the rest is non-magnetic steel slag; The calculation formula of the maximum mass of siderite that can be added is as follows: wherein: is the maximum mass of siderite that can be added / kg, is the specific heat capacity of the steel slag / (kJ / (kg·°C)), is the mass of the steel slag / kg, is the temperature of the steel slag / °C, is the latent heat of phase transition of the steel slag / (kJ / kg), is the specific heat capacity of the ore / (kJ / (kg·°C)), is the proportion of FeCO3 in the siderite, is the latent heat of decomposition of FeCO3 / (kJ / kg), is the calorific value of the coke / (kJ / kg); The calculation formula of the time corresponding to the slag temperature is as follows: In the formula: t is the slag temperature corresponding time / s with the time point when adding siderite as time zero, is the specific heat capacity of steel slag / (kJ / (kg·℃)), is the mass of steel slag / kg, is the temperature of steel slag / ℃, is the target temperature / ℃, is the latent heat of phase transition of steel slag / (kJ / kg), is the specific heat capacity of ore / (kJ / (kg·℃)), is the mass of added siderite / kg, is the thermal diffusivity of steel slag / (m 2 / s), is the liquid surface area of steel slag / m 2 , is the blackbody radiation constant / (W / (m 2 ·K 4 )), is the density of steel slag / (kg / m 3 ).

2. The production method of wustite by steel slag waste heat temperature control treatment according to claim 1, characterized in that, The siderite is crushed to a diameter of less than 30 mm.

3. The production method of wustite according to claim 2, wherein In step S2, the amount of coke added is 4%-7% of the mass of the siderite.

4. The production method of wustite according to claim 1, wherein The effective component in the steel slag is CaO, and the effective component in the coke is C.

5. Product obtained by the production process according to any one of claims 1 to 4, characterized in that, The non-magnetic steel slag contains calcium ferrite.

6. Use of a product according to claim 5, characterized in that, The obtained non-magnetic steel slag is applied to converter smelting, and the addition amount of non-magnetic steel slag in one furnace is not more than 500 kg.

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