Burner backflow reduction in regeneration furnace

In the present case from the steel industry, waste hydrochloric acid from the pickling process is regenerated using spray roasting. The process is driven by four burners placed symmetrically along the periphery of the cylindrical main section of the reactor. Severe problems with gas backflow and sintering of iron oxide inside the burner chamber have led to a complete shut down of the process 1-2 times every week, which is a frequency which significantly affects the productivity. In this study the influence of a kick-out on the gas flow in the vicinity of the burner chamber is investigated numerically. It is shown that the kick-out geometry creates a vortical low pressure region preventing the inflow of gas and hence the sintering of iron oxide. This has led to a significant increase in the productivity with no additional shut-downs than needed for the ordinary maintenance every 6-8 weeks.