Method for predicting reaction equilibrium components of steel slag
By building a steel-slag reaction calculation platform in the FactSage platform and performing repeated calculations in combination with on-site temperature difference, the problem of inaccurate calculation results of the double-membrane theoretical model is solved, and accurate prediction of steel slag reaction components is achieved, reducing the production cost of steelmaking plants and improving production efficiency.
Patent Information
- Application Number
- CN202510291216.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-12
- Publication Date
- 2025-07-08
AI Technical Summary
The existing steel slag reaction prediction model constructed by the double-membrane theory has the problem of inaccurate calculation results, which is difficult to meet the actual needs of the steelmaking site.
A steel-slag reaction calculation platform was constructed, macro commands were edited in FactSage, and repeated calculations were performed in combination with on-site temperature difference to predict the composition changes in the steel slag reaction. The steel-slag reaction was simulated through the FactSage calculation platform, and the CaO-SiO2-Al2O3-MgO quaternary refined slag system was used for simulation. The steel slag ratio was set to 10:3, the reaction time was 60min, and the temperature range was 1580℃-1620℃. The average value was taken as the final result.
It improves the accuracy of steel slag reaction components prediction, reduces the production costs of steel mills, improves production efficiency, and provides theoretical support for the green development of the steel industry.
Smart Images
Figure CN120280009A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a method for predicting the equilibrium composition of steel slag reaction, belonging to the technical field of steelmaking methods in the metallurgical industry. Background Art
[0002] Since refining slag plays a very important role in the steelmaking process, improving the cleanliness of molten steel through the steel-slag reaction has always been a research hotspot in the metallurgical industry. First of all, the refining slag can be used as a foaming agent to remove impurity gases such as oxygen and sulfur in the molten steel. Secondly, the refining slag can adsorb large-size and irregular non-metallic inclusions in the steel, thereby improving the fatigue performance of the steel. In addition, the refining slag can also be used as a protective slag to isolate the air and prevent the secondary oxidation of the molten steel. However, if the proportion or addition amount of the refining slag is inappropriate, it is easy to cause problems such as difficult slag melting and erosion of the furnace lining, which will in turn affect the quality of the steel and reduce the production efficiency. Therefore, predicting the result of the steel-slag reaction can clarify the component ratio of the refining slag in advance, judge the excellent performance of the refining slag, optimize the process parameters, and can also improve problems such as nodulation of the tundish nozzle, and improve the continuous casting efficiency. Thereby improving the service life of the furnace lining and saving the production cost of the steel plant.
[0003] At present, most of the steel slag reaction prediction models are constructed based on the double-film theory. However, there are too many limiting factors for constructing the steel slag reaction kinetic model through the double-film theory. First, it is necessary to determine that there are boundary films on both sides of the phase interface, that is, the concentration boundary layer. Secondly, the interface between the two phases is in a dynamic equilibrium state, and the diffusion flux of the components within each phase is proportional to the concentration difference within the phase and at the interface. Finally, it is considered that the fluid in the boundary layer is in a static state, not affected by the flow state within the phase, and the mass transfer within each phase is independent, and the two phases do not affect each other. In addition, the limiting link of the liquid-liquid phase reaction needs to be considered. Therefore, it is difficult to ensure the accuracy of the calculation results by constructing a steel slag reaction prediction model through the double-film theory. FactSage is one of the most comprehensive calculation systems integrating chemical thermodynamics databases in the world today. It runs on personal computers on the Microsoft Windows platform and consists of a series of information, databases, calculation and processing modules. These modules use various pure substance and solution databases. FactSage already has hundreds of users in the industrial, government and academic fields, and its application scope includes materials science, pyrometallurgy, hydrometallurgy, electrometallurgy, corrosion, glass industry, combustion, ceramics, geology, etc. With the increasingly rich application scenarios of FactSage in the metallurgical field and the continuous update of the FactSage database, calculating the steel slag reaction by FactSage has become a new calculation method. Compared with the traditional double-film theory calculation, the limiting conditions for calculating the steel slag reaction by FactSage are relatively few, the calculation scenario fits the actual steelmaking site, and the calculation results are more accurate. Summary of the Invention
[0004] The object of the present invention is to provide a method for predicting the equilibrium composition of steel slag reactions. By constructing a steel-slag reaction calculation platform, editing macro command calculation instructions in FactSage, and combining on-site temperature differences to repeatedly calculate the reactions, the composition of the entire steel-slag reaction process is predicted, and the performance of the refining slag is evaluated in advance, providing a certain theoretical basis for on-site production in steel mills, thereby effectively reducing the costs of steel mills, improving production efficiency, and contributing to the green development of the iron and steel industry, effectively solving the above problems existing in the background technology.
[0005] The technical solution of the present invention is: a method for predicting the equilibrium composition of steel slag reactions, comprising the following steps: S1. Construct a steel-slag reaction calculation platform and input parameters such as liquid steel composition, refining slag composition, reaction time, and reaction temperature; S2. Set calculation instructions in FactSage, read the parameters in the calculation platform, and construct Reaction 1: The initial liquid steel reacts with the initial liquid slag to produce the reacted liquid steel phase and liquid slag phase; S3. Set calculation instructions in FactSage, read the parameters in the calculation platform, and construct Reaction 2: The liquid steel phase that reacts in Reaction 1 reacts with the unreacted initial liquid steel to produce a new homogeneous liquid steel phase; S4. Set calculation instructions in FactSage, read the parameters in the calculation platform, and construct Reaction 3: The liquid slag phase that reacts in Reaction 1 reacts with the unreacted initial liquid slag to produce a new homogeneous liquid slag phase; S5. Repeat the above reaction stream for a certain period of time to obtain the variation relationship of the component contents in the liquid steel and liquid slag with the reaction time at a certain specific temperature; S6. Due to temperature fluctuations in on-site production, according to the actual on-site temperature difference, repeatedly calculate the steel-slag reactions at each temperature within the temperature difference range, and take the average value of the calculation results as the final prediction result of the steel-slag reaction composition.
[0006] In Reaction 1, Reaction 2, and Reaction 3, since the steel-slag reaction does not reach an equilibrium state at the beginning, in the initial stage of the steel-slag reaction, part of the liquid steel reacts with the liquid slag; the liquid steel and liquid slag during the reaction are homogeneous liquid phases, the inclusions in the liquid steel and liquid slag do not react, and the reaction temperature is constant; the reaction occurs at the steel-slag interface.
[0007] In step S5, the temperature during the steel-slag reaction calculated by FactSage is a single constant, so the variation relationship of the component contents in the liquid steel and liquid slag with the reaction time at a certain specific temperature will be obtained.
[0008] Taking the composition of advanced dual-phase steel DP590 for automobiles as a parameter, a CaO-SiO2-Al2O3-MgO quaternary refining slag system is used for the steel-slag reaction simulation. The steel-slag ratio is 10:3, the reaction time is set at 60 minutes, and the step size is 1 minute. The reaction temperature is set at 1580°C - 1620°C. At each temperature, the steel-slag reaction equilibrium process is simulated, the reaction results are calculated in turn, and the average value of the calculation results is taken as the final prediction result of the steel-slag reaction composition.
[0009] The beneficial effects of the present invention are as follows: By constructing a steel-slag reaction calculation platform, editing macro command calculation instructions in FactSage, and combining on-site temperature differences to repeat the calculation of the reaction, the composition of the entire steel-slag reaction process is predicted, and the performance of the refining slag is evaluated in advance, providing a certain theoretical basis for on-site production in steel mills, thus effectively reducing the costs of steel mills, improving production efficiency, and contributing to the green development of the steel industry. Brief Description of the Drawings
[0010] Figure 1 is the flowchart of the method of the present invention. Detailed Embodiments
[0011] In order to make the objectives, technical solutions, and advantages of the invention implementation cases clearer, the technical solutions in the invention implementation cases will be clearly and completely described below in conjunction with the drawings in the implementation cases. Obviously, the described implementation cases are a small part of the implementation cases of the present invention, rather than all of the implementation cases. Based on the implementation cases of the present invention, all other implementation cases obtained by those of ordinary skill in the art without creative efforts belong to the protection scope of the present invention.
[0012] A method for predicting the equilibrium composition of steel-slag reaction includes the following steps: S1. Construct a steel-slag reaction calculation platform and input parameters such as liquid steel composition, refining slag composition, reaction time, and reaction temperature; S2. Set calculation instructions in FactSage, read various parameters in the calculation platform, and construct Reaction 1: The initial liquid steel reacts with the initial liquid slag to produce the reacted liquid steel phase and liquid slag phase; S3. Set calculation instructions in FactSage, read various parameters in the calculation platform, and construct Reaction 2: The liquid steel phase that has reacted in Reaction 1 reacts with the unreacted initial liquid steel to produce a new homogeneous liquid steel phase; S4. Set calculation instructions in FactSage, read various parameters in the calculation platform, and construct Reaction 3: The liquid slag phase that has reacted in Reaction 1 reacts with the unreacted initial liquid slag to produce a new homogeneous liquid slag phase; S5. Repeat the above reaction stream for a certain period of time to obtain the relationship between the component contents in the molten steel and the molten slag and the reaction time at a specific temperature. S6. Since the temperature fluctuates in on-site production, according to the actual temperature difference on-site, recalculate the steel-slag reaction at each temperature within the temperature difference range, and take the average value of the calculation results as the final prediction result of the steel-slag reaction components.
[0013] In the above Reaction 1, Reaction 2, and Reaction 3, since the steel-slag reaction does not reach an equilibrium state at the beginning, in the initial stage of the steel-slag reaction, part of the molten steel reacts with the molten slag; the molten steel and the molten slag during the reaction are homogeneous liquid phases, inclusions in the molten steel and the molten slag do not react, and the reaction temperature is constant; the reaction occurs at the steel-slag interface.
[0014] In step S5, the temperature during the steel-slag reaction calculated by FactSage is a single constant value. Therefore, the relationship between the component contents in the molten steel and the molten slag and the reaction time at a specific temperature will be obtained.
[0015] Taking the composition of advanced dual-phase steel DP590 for automobiles as a parameter, a CaO-SiO2-Al2O3-MgO quaternary refining slag system is used for the steel-slag reaction simulation. The steel-slag ratio is 10:3, the reaction time is set to 60 min, and the step size is 1 min; the reaction temperature is set to 1580 °C - 1620 °C. The steel-slag reaction equilibrium process is simulated at each temperature, the reaction results are calculated in turn, and the average value of the calculation results is taken as the final prediction result of the steel-slag reaction components. Example
[0016] In this example, taking the composition of the current popular advanced dual-phase steel DP590 for automobiles as a parameter, a CaO-SiO2-Al2O3-MgO quaternary refining slag system is used for the steel-slag reaction simulation. The steel-slag ratio is 10:3, and the reaction time is set to 60 min with a step size of 1 min. The parameters are input into the steel-slag reaction calculation platform.
[0017] The steel-slag reaction is not always in an equilibrium state but gradually moves towards the equilibrium direction with the reaction time. Therefore, at the beginning of the steel-slag reaction, part of the molten steel reacts with the molten slag. Calculate Reaction 1 by FactSage: the reaction of part of the initial molten steel and part of the molten slag. Calculate Reaction 2 by FactSage: the reaction of the reacted molten steel and the remaining unreacted molten steel to produce a new homogeneous molten steel. Calculate Reaction 3 by FactSage: the reaction of the reacted molten slag and the unreacted molten slag to produce a new homogeneous molten slag. And save the calculation processes of the three reactions.
[0018] Write the FactSage macro command calculation program through NotePad++, call the calculation instructions in FactSage, and read the parameters in the calculation platform. Substitute the parameters into the calculation processes of the three reactions and repeat the calculation process a certain number of times to obtain the relationship between the steel-slag component content and the reaction time at a specific temperature.
[0019] Due to the fluctuation of the on-site furnace temperature, repeat the calculation every 1 °C within the temperature difference range as the calculation temperature of the steel-slag reaction, and take the average value of the calculation results to obtain the final reaction results of DP590 dual-phase steel and CaO-SiO2-Al2O3-MgO quaternary refining slag.
Claims
1. A method for predicting the equilibrium composition of steel slag reactions, characterized in that It includes the following steps: S1. Build a steel - slag reaction calculation platform and input parameters of molten steel composition, refining slag composition, reaction time, and reaction temperature; S2. Set calculation instructions in FactSage, read various parameters in the calculation platform, and construct Reaction 1: The initial molten steel reacts with the initial liquid slag to produce a reacted molten steel phase and a liquid slag phase; S3. Set calculation instructions in FactSage, read various parameters in the calculation platform, and construct Reaction 2: The molten steel phase that reacts in Reaction 1 reacts with the unreacted initial molten steel to produce a new homogeneous molten steel phase; S4. Set calculation instructions in FactSage, read various parameters in the calculation platform, and construct Reaction 3: The liquid slag phase that reacts in Reaction 1 reacts with the unreacted initial liquid slag to produce a new homogeneous liquid slag phase; S5. Repeat the above reaction flow for a certain time to obtain the variation relationship of the component contents in molten steel and liquid slag with reaction time at a certain specific temperature; S6. Due to temperature fluctuations in on - site production, according to the actual temperature difference on site, repeat the calculation of the steel - slag reaction at each temperature within the temperature difference range, and take the average value of the calculation results as the final prediction result of the steel - slag reaction components.
2. The method for predicting the equilibrium composition of steel slag reaction according to claim 1, wherein: In Reaction 1, Reaction 2, and Reaction 3, since the steel - slag reaction does not reach an equilibrium state at the beginning, in the initial stage of the steel - slag reaction, part of the molten steel reacts with the liquid slag; the molten steel and liquid slag during the reaction are homogeneous liquid phases, inclusions in the molten steel and liquid slag do not react, and the reaction temperature is constant; the reaction occurs at the steel - slag interface.
3. A method for predicting the equilibrium composition of steel slag reaction according to claim 1, characterized in that: In Step S5, the temperature during the steel - slag reaction calculated by FactSage is single and unchanged, so the variation relationship of the component contents in molten steel and liquid slag with reaction time at a certain specific temperature will be obtained.
4. A method for predicting the equilibrium composition of steel slag reaction according to claim 1, characterized in that: Taking the composition of advanced dual - phase steel DP590 for automobiles as parameters, a CaO - SiO2 - Al2O3 - MgO quaternary refining slag system is used for steel - slag reaction simulation. The steel - slag ratio is 10:3, the reaction time is set to 60 min, and the step size is 1 min; the reaction temperature is set to 1580℃ - 1620℃. Simulate the steel - slag reaction equilibrium process at each temperature, calculate the reaction results in sequence, and take the average value of the calculation results as the final prediction result of the steel - slag reaction components.