| dc.description.abstract | The retrofit of a 35000 hp, two-case centrifugal, propylene refrigeration compressor with tandem dry gas seals in DuPont's ethylene plant at Orange, Texas, is described. The installation of these dry gas seals is one of the first applications to propylene refrigeration service in the United States. The new seal design eliminated seal oil contamination of the compressor and downstream heat exchangers which led to decreased efficiency, effectiveness, and subsequent loss of ethylene production. The seals also reduced the capital investment for a flare system upgrade project $1.5MM, by decreasing propylene losses during system shutdowns caused by existing seal system shortcomings. This retrofit was unique in several ways. The original compressor manufacturer had no experience with dry gas seals installed in their equipment. They were very willing to cooperate in this venture, but only to the point of providing dimensional data and engineering review. Due to the "sold-out" condition of the ethylene market, this installation had to be accomplished during a limited shutdown. In order to minimize downtime, an innovative installation method was developed which eliminated opening compressor casings even though the new design required removing-a shaft sleeve. To demonstrate the feasibility of this method, a mock up was built simulating working conditions to develop techniques and tooling to remove the shaft sleeve. | en |
