Defining the Process Simulation

1. Add a Process Metallurgy Calculator node to My Projects node. If you used the Process Metallurgy template on the My Projects Configuration window under Applications), click the node to display the Configuration settings window.

2. Under Kinetics, choose the simulation type, Equilibrium or Process simulation. For the following steps, choose Process simulation.

   Only adiabatic conditions are available for process simulations as this corresponds best to most practical processes.

Process Simulation: Conditions Tab

1. In the Configuration window, for the Database selection, the program automatically defaults to the highest available version of the TCOX database.

   The Process Metallurgy Module requires both a valid Maintenance and Support Subscription (M&SS) and a license for the TCS Metal Oxide Solutions Database (TCOX8 or newer).

   It is not possible to use custom user databases with the Process Metallurgy Module. This is because several internal calculations, such as determining the component compositions of ionic phases, are dependent on the database. Therefore, only TCS Metal Oxide Solutions Database (TCOX) versions 8 and newer, and to a limited extent, OXDEMO, can be used with this Module.

   All users can test the Process Metallurgy Module with the included OXDEMO database, which is limited to these elements: Al, C, Ca, Fe, O, S, and Si. For more information about this and other products visit our website.

2. Select a Temperature unit (Kelvin, Celsius, or Fahrenheit).
3. Select a Time unit (Seconds, Minutes, Hours, or Days).

Process Simulation: Process Model Settings

1. Enter a Name for the process and the total Duration of the process.
2. Choose a Process model from the list or click Edit Process Model to define a new model or edit an existing one.

3. In the Process model the following is defined:

   1. Pressure. This is can be either Constant throughout the process (enter a constant via the Edit Process Model) or be changed during the process (select Table input via the Edit Process Model) and then enter pressure in the Process schedule table.
   2. Zones of the Effective Equilibrium Reaction Zone model. Only two zones can be defined. The densities need to be given manually. They are used to calculate the volume of the reaction zones, which is in turn used for the calculation of the reaction kinetics. Choose to allow degassing or not.
   3. Area of the Reaction zone and mass transfer coefficients. The area is typically the area of the interface between the two zones. The mass transfer coefficients state how fast material is moved into the reaction zone. Large values result in fast kinetics, small numbers in slower kinetics. These values strongly depend on the type of material (mass transfer in slags is slower than in liquid steel due to its higher viscosity) and type of process (the violent reactions in a basic oxygen furnace have higher mass transfer coefficients compared to the gentle stirring performed in a ladle furnace. These parameters are basically fitting parameters that need to be determined based on comparison with experimental data. Typical values can also be found in the literature. Choose to allow degassing or not.
   4. Transfer of phase group. This defines how fast “foreign” phases are moved from one zone to the other. Foreign phases could be solid or liquid oxide inclusions in the liquid steel, or metallic droplets in the slag phase. A typical application is the simulation of the flotation of oxide inclusions out of the liquid steel into the slag phase during refining in a ladle furnace.
   5. The Heat entering or leaving the system and being transferred between the zones. Constant cooling defines how much heat is lost from the system by radiation and convection. Separate values can be given to each zone if needed. Heat is used when the system is actively heated by an external heat source such as an electric arc or induction heater. Here only the heating efficiency is given, which is the percentage of for example electrical power that is transferred to the system as heat. The times and power are defined in the Process schedule. Different amounts of heat and material are added to the zones resulting in the zones having different temperatures. Heat transfer defines how heat flows from one zone to the other. A high value results in a quick equalization of temperature, a small value results in the zones keeping their different temperatures.

Process Simulation: Materials Tab

The materials can be defined, saved and retrieved in the same way as for an equilibrium simulation. For a process simulation, it must be defined to which zone the material is added. Typically, oxide materials are added to the slag zone and metallic materials are added to the steel zone. Gas or other injected materials (such as carbon or lime powder) are typically added to the reaction zone. But this choice depends on the process to be simulated and must be carefully chosen. By defining the same material twice or even three times, it can be split, so that part of the material is added to one zone and part of it to another zone.

Working with the Process Schedule

Process Simulation: Process Schedule Tab

On the Process schedule tab, the sequence and amounts of additions during the duration of the process are defined. All the materials defined in the Materials tab automatically are included in the table. If a heat addition is defined in the Process Model this is also included in the table. If the units Tonne, Kilogram, or Pound are selected, then the additions are defined as one-time additions at a certain time. If a rate is chosen as unit of the addition (such as Kilogram per minute or Kilogram per second, for gas also Normal cubic meter per minute or per second can be given) then the rate of addition is entered into the table. The additions are visualized in a plot for clarity.

When the simulation is set up, click Perform Tree to run it. Plots and tables can be added in the same way as for equilibrium calculations.