Steam ejectors have now become the established pumping system for degassing molten steel because of their high gas handling capacities at low pressures. The stream and ladle degassing processes are described including plant required in addition to the ejectors. Theoretical consideration is given to the operation of a steam ejector, and the design requirements for a complete multi-stage plant to operate at less than 1 torr are discussed.
Finally the economies and benefits derived from the processes are outlined and future trends indicated.
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