Praxair awarded patent for post-combustion technology.

DANBURY, Conn.--(BUSINESS WIRE)--Dec. 3, 1996--Praxair, Inc. (NYSE:PX) announced today it has received U.S. Patent No. 5,572,544 for its electric-arc furnace post-combustion steel making technology. Praxair's proprietary technology significantly improves productivity and decreases electrical energy consumption and hazardous emissions in electric arc furnace-based steel making mills. Praxair's technology combusts carbon monoxide that is produced during melting and refining to carbon dioxide, efficiently transferring the resultant heat to the molten bath.

"The award of a patent for Praxair's post-combustion technology is significant, because it offers our customers a competitive advantage in their production processes," said Ron Selines, steel applications manager, Praxair. "Our simple and unique approach has resulted in higher heat recovery and post-combustion oxygen utilization than customers can achieve using other processes, as demonstrated by consistent energy savings of 4.5 kilowatt hours for each cubic meter of post-combustion oxygen used in the electric- arc furnace."

To date, Praxair has converted seven electric-arc furnaces to its post-combustion technology, representing 3.4 million tons (3.1 million metric tons) of annual production capacity. On average, steel producers using this technology have realized productivity improvements of up to seven percent, electrical energy consumption reductions ranging from seven to 10 percent, and as a much as a 40 percent decrease in carbon monoxide emissions.

Worldwide, there are approximately 1,000 steel mills using electric-arc furnaces, representing annual production of 264 million tons (240 metric tons). Praxair expects to convert two additional furnaces by the end of 1996, and another eight during 1997.

Selines estimates a typical steel maker with 750,000 tons of annual production capacity could save approximately $2.5 million by utilizing post-combustion technology.

"The placement of the oxygen-injection lances is critical to the efficiency of the post-combustion process," Selines added. "Our engineers have found that placing the lances relatively low in the furnace maximizes heat transfer to scrap and slag, which also makes it the process of choice for furnaces using significant quantities of alternative iron units."

In addition to leading-edge technology, Praxair supplies steel producers with oxygen from on-site cryogenic facilities, pipelines, vacuum pressure swing adsorption (VPSA) systems or trucked-in liquid from the company's strategically-located air separation plants, depending on specific customer needs.

Praxair is the largest industrial gases company in North and South America, and one of the largest worldwide, with annual sales of more than $4 billion. The company produces, sells and distributes atmospheric, process and specialty gases and high-performance surface coatings. Praxair is also the world's largest supplier of carbon dioxide and a recognized leader in the commercialization of new technologies that bring productivity and environmental benefits to a diverse group of industries.

CONTACT: Keith Bisogno, 203/837-2032