Danieli's Entry into Direct Reduction with its Danarex Process
Danieli entered into the DR field in order to offer its clients complete facilities for steelmaking— from processing of raw materials through finished products. The Danarex Process for producing a passivated product, called the Supermetallic (SPM), without hot-briquetting is described. One of the main features of the Danarex Process is its ability to produce approximately 50% of the DRI through reduction gas generated in a reformer and another 50% through recycling preheated furnace exit gas. Other distinguishing features, such as the separation of carburising and cooling zones, are also described.
A pilot plant was set up at Hazen Research Inc., Golden, CO in order to show that the integrated process works as expected and to obtain process data. The pilot plant set up and the results obtained are then presented. The SPM obtained was of a very high quality, evidenced by metallization levels of 92% to 98%. The carbon content could be controlled between 1.5% to 4.0% by varying the operating conditions and approximately 75% of this carbon was present as
Fe3C.The product was tested for passivity by Chilworth Technology, England, using UN standard tests and was found to be safe for outdoor storage and transportation.
Finally, the paper will describe how the process would be controlled to maintain the variations in product quality within a narrow range. In addition to routine process control through adjustments of variables, the use of Statistical Process Control (SPC) and Management Accounting Techniques will be described. Contrary to the guidelines followed in many operating plants that operating personnel should only “do” and not “decide”, separation of decision-making by floor level personnel and management will be described.
Direct reduction, Iron making, SPC, Danarex