 The study investigated the effects of various carbon sources on slag foaming behavior. The results indicated that biochar had the least favorable foaming characteristics compared to the other tested carbon sources. However, when mixed with 50 weight percent coke, the foaming characteristics were comparable to those of conventional carbon sources. This suggests that biochar can be used as a viable alternative to traditional carbon sources in steel-making processes. This article was authored by Lina Kyush, Johannes Schenck, Andriy Koviria, and others.