China’s Chong Qing Steel Group Co. placed an order with Edwards for the world’s largest dry mechanical vacuum pumping system. When installed, the system will be capable of pumping 1,000,000 m3/h at 0.67 mbar and will degas 230-metric-ton quantities of liquid steel in each batch. It will be the world’s first application of dry vacuum pumps to a Ruhrstahl Heraeus steel degassing process. The system provides Chong Qing Steel with potential energy cost savings of more than 90% over traditional steam ejector systems. Edwards will supply 18 steel degassing “supermodules,” each comprising twin 40,000-m3/h mechanical boosters backed by a common 8,000-m3/h booster and one of the latest generation IDX1300 dry screw pumps.

Other benefits of the system include: a lower environmental impact through reducing water effluent and CO2 emissions; optimized steel quality due to no moisture contamination and consistent performance; and increased safety through removing the need for high-pressure steam. The total value of the contract is in excess of $8 million – Edwards’ largest single project order in the metallurgical market. Delivers to Chong Qing Steel will be completed by the end of the year.