Due to the increasing effects of climate change on our economic- and ecological system, many areas are changing. Especially industry and the important topic of processing residuals and recycling of the valuable metals. The focus of this work is the processing of zinc containing steel mill dust. Due to the high demand for galvanized automobile and construction industry, large amounts of zinc end up in the dust of the steel plants where the zinc coated steel scrap is recycled after its lifetime. The main part of these dusts is processed in the Waelz process, with the only aim of zinc recovery. Other elements contained in the steel mill dust such as iron or lead are not considered in this type of processing. A solution for a multi metal recycling can be carried out on a carbon-saturated metal bath. The focus of the present work is on the carbothermal and metallothermic reduction processes of iron- and zinc oxide using a metal bath. For this purpose, reduction tests were carried out on liquid iron baths with defined carbon content (1, 2, 3, 4 %). To realize industrial process conditions, a synthetic slag with a basicity B2 = 1 was used and washed Waelz oxide served as zinc source. The slag- and iron samples were analyzed using SEM-EDX as well as spark emission spectrometry and results are discussed.