During the last 20 years, the U.S. steel industry has undergone a drastic and painful restructuring process that resulted in a 30% reduction in capacity and a loss of 375,000 jobs. Over half the integrated mills shut down or de-integrated their operations. Minimills emerged as a capital and labor efficient alternative for producing commodity steel products. During this period the industry invested heavily in new technology so that now, nearly 90% of steelmaking comes from continuous strand casting eliminating the ingot teeming, soaking pits, and ingot breakdown mills. Further, all of the obsolete open hearth steelmaking operations have now been closed down. Integrated producers are also seeking to reduce or eliminate coke requirements through coal, gas, or oil injection in blast furnaces, or through entirely new cokemaking, ironmaking, or steelmaking processes. Pulverized coal injection in blast furnaces is having the most impact currently with the more advanced concepts being explored as R&D.

The most important trend occuring today is the entry of the larger minimills into the flat rolled products business with the aid of thin slab casting technology and compact strip mill configurations that eliminate slab inventory and reheating. The planned entry of several new producers in this market will create a very competitive situation in the future as there is already sufficient capacity to meet demand. As minimills attempt to compete for higher quality products, there will be a greater dmeand for pig iron, direct reduced iron, and iron carbide to improve the quality of the product from 100% scrap fed electric arc furnaces. Another trend related to minimills is the rapid growth of steel processors specializing in pickling, slitting, blanking, and other finishing operations that are forming satellite rings around the new minimills.

Hogan, W.T. Steel in the 21st Century, Lexington Books, New York, 1994