May 1 2007
Praxair, Inc. announced today that it has licensed its 100th patented electric arc furnace (EAF) CoJet gas injection system to Nanjing Iron & Steel United Co., Ltd., which is also the fourth major Chinese steel manufacturer in two years to choose the CoJet system for electric arc furnaces.
The CoJet system makes it more economically feasible for steel manufacturers to use higher amounts of hot metal charge in their furnaces. Once the installation is complete, Nanjing Iron & Steel will be able to use a predominately hot metal feed to refine into steel, thereby reducing energy consumption and eliminating the need for electric arcs entirely, if desired.
The CoJet technology also allows steel manufacturers to quickly and easily remove carbon, in order to produce steel, from the hot metal feed by injecting a laser-like supersonic jet of oxygen into the molten bath. Another benefit to using the CoJet gas injection system is that it can help minimize hot metal splashing in the furnace, which can damage the furnace roof and other parts if not properly controlled, while allowing even mixing of the molten bath.
"Although the CoJet technology was originally developed a decade ago, our leading-edge design combined with our technological expertise still makes us the preferred supplier in the steel industry today," said Pravin Mathur, director of Steel Business Development for Praxair. "We continue to look for ways to improve this process, which includes researching alternative fuel sources."
Nanjing Iron & Steel United Co., Ltd. is one of the largest industrial enterprises in the Jiangsu Province of China, located along the Yangtze River. The company's business operations include mining and concentrating, iron and steel making, and steel rolling. Nanjing's plant is equipped with ultra-high-power EAFs primarily used for wire and rod production. The company selected Praxair's CoJet technology to help enhance their competitive capability while improving productivity and decreasing cost.