25 percent Increased Reheating Throughput and 50 percent Reduced Fuel Consumption by Flameless Oxyfuel at ArcelorMittal Shelby - Tubular Products, Ohio

摘要

ArcelorMittal Shelby and Linde began in 2004 to jointly work to improve the reheating process in an existing rotary hearth furnace. The methodical implementation of the Linde REBOX~R oxyfuel solutions has rapidly and cost-efficiently brought long-term, viable results without a long project period or extensive production downtime. In 2005, a 5 percent oxygen enrichment of the airfuel system delivered a 29 percent specific gross fuel savings. Later, ArcelorMittal Shelby wanted to boost capacity, especially for large size billets, and in 2007 Linde was awarded a turnkey project for a full conversion of the same rotary hearth furnace to flameless oxyfuel technology. Several process parameters have been monitored prior to and after the re-start of the furnace at the end of August 2007 and the important result of the project are summarized as follows. An overall capacity increase of 25 percent for billet dimensions 6" and larger; Specific gross fuel savings of 50 percent over oxygen enriched airfuel and 65 percent over the original airfuel; Improved temperature uniformity with 50 percent less temperature differences over billet length; A 50 percent reduction in scale formation; Annual NO_x emissions lowered by 76 percent; a 50 percent reduction in CO_2 emissions over oxygen enriched airfuel and 65 percent reduction over the original airfuel; A short, four month, timeline for implementation and on-time commissioning; Project payback within 24 months.