The design and control of blast furnace (BF) ironmaking must be optimized in order to be competitive and sustainable, particularly under the more and more demanding and tough economic and environmental conditions. To achieve this, it is necessary to understand the complex multiphase flow, heat and mass transfer, and global performance of a BF. In this paper injection of alternative reducing agents via lances in the tubers of blast furnaces is discussed to reduce the consumption of metallurgical coke. Besides liquid hydrocarbons and pulverized coal the injection of recycled waste plastics is possible, offering the opportunity to chemically reuse waste material and also utilize the energy contained in such remnants.