Method for monitoring the wear of a refractory lining of a blast furnace

A method for monitoring the wear of a refractory lining of a blast furnace, the method comprising, using a computer:

• a. modelling in at least two dimensions at least a part of the blast furnace at an initial known state;
• b. defining internal thermal boundary conditions and external thermal boundary conditions of the modelized part of step (a);
• c. calculating a thermal field within said modelized part of the blast furnace considering refractory lining thermal characteristics and the internal and external thermal boundary conditions, said thermal field including a temperature field and heat path lines (Ln), a starting point of each path line (Ln) being a measurement point (Pn) and an end point being the internal boundary;
• d. measuring, by thermal sensors, a temperature (Tmeas_n) at each measurement point (Pn), the thermal sensors being embedded at least per two at the same height of the wall or width of the pad, but each of the two being embedded at a different depth within the refractory lining, each group of thermal sensors forming one of the measurement points (Pn);
• e. based on the thermal field calculation of step (c):
• e1—using the measured temperature (Tmeas_n) at each measurement point (Pn) as a starting value, moving a control point (Xn) along each heat path line (Ln) and determining a position (In) where said control point (Xn) reaches a critical temperature Tcrit,
• e2—determining a position of the hot metal solidification isotherm, said isotherm being a curve linking all previously determined positions (In) at which the critical temperature Tcrit is reached;
• f. calculating a new thermal field using the previously determined position of the hot metal solidification isotherm as new internal thermal boundary conditions;
• g. estimating a temperature Test_n at each measurement point (Pn) using the newly calculated thermal field;
• h. calculating a convergence criterion CC between each estimated temperature Test_n and respective measured temperature Tmeas_n;
• if this convergence criterion CC is below a predefined target Δ, determining a wear surface of the refractory lining based on the position of the hot metal solidification isotherm,
• if this convergence criterion CC is above the predefined target Δ, iterating steps e to h until the convergence criterion CC is below the predefined target Δ;
• and
• i. outputting the wear surface of the refractory lining determined based on the position of the hot metal solidification isotherm to identify a portion of the refractory lining as being a damaged portion based on the position of the hot metal solidification isotherm.