Optimal Control of the Argon Oxygen Decarburizing Steelmaking Process

The argon oxygen decarburizing process is an increasingly important method of stainless steel manufacture. In the present paper, a nonlinear dynamic model is presented which represents approximately, the refining process. Finite dimensional optimisation techniques are used to calculate an optimal switched control and infinite dimensional gradient methods are applied to to discover an optimal continuous strategy. Control is achieved by varying the ratio of argon and oxygen in the supplied gas. Results with a realistic cost function indicate that substantial improvements in operating practice may be achieved. The feasibility of implementing the suggested control schemes is discussed