9424069 Pal A solid state sensor will be designed and built to in-situ monitor oxide (slag) melt composition encountered in smelting and refining of ferrous and non-ferrous metals. In this device, the oxygen ion conducting stabilized zirconia solid electrolyte will physically separate the cathodic compartment, exposed to the melt, from the anodic compartment, exposed to a reference gas. Possible choices for electrode materials include refractory oxides such as the lanthanum and yttrium chromites, doped zirconia and various inert metal-zirconia cermets. A negative potential sweep, will be applied to sensing electrode (cathode) with respect to the counter electrode (anode). When the dissociation potential of an oxide in the melt is reached, the oxide will reduce at the cathode and the oxygen ions will be driven through the solid electrolyte to the anode, where they will liberate electrons and an ionic current through the device will be detected. If the oxides in the melt, which are to be detected, have dissociation potentials that do not overlap and are lower than that of zirconia, then these oxides can be sequentially dissociated and distinguished by this device. Once an oxide is dissociated, the potential sweep will result in an ionic current peak which will give a measure of its concentration. By using a single device one could detect and measure the concentrations of the oxides of iron, manganese and chromium in ferrous smelting and refining slags. The sensor will be tested on three well defined slag systems, CaO-SiO2-Al2O3-Feo, CaO-SiO2-Al2O3-FeO-MnO, and CaO-SiO2-A12O3-FeO-MnO-CrOx. The industrial partner will package this slag sensor for on-site testing in steelmaking facilities. Proper real time detection of FeO and MnO in steelmaking and ladle refining slags and also CrOx in stainless steelmaking slags is key to improving the recovery of iron and alloying elements and decreasing non-metallic inclusions through better process control. For optimum process control of ferrous and non-ferrous smelting and refining operations, concentration of some critical components in slags need to be monitored in real time at various stages during the process. Currently, all slag composition analyses in these processes are performed with expensive analytical equipment on samples removed from the melt and they take a relatively long time. If in-situ monitoring of slag composition can be performed using a relatively inexpensive sensor it would be widely used for smelting and refining process control, resulting in improving the quality of the product, increasing productivity and thereby decreasing the overall manufacturing cost.
