Environmental Aspects of Reactive Metal Production Available to Purchase

If vacuum metallurgy were the segment of the production of reactive metals with which one needed to be concerned, environmental aspects would be relatively simple to control. Air pollution could be handled by proper use of vapor and mist traps on mechanical pump exhausts and in the vicinity of oil reclaimers. Prevention of water pollution might prove to be more of a problem because of the difficulties in disposing of both mechanical pump and diffusion pump oils. An integrated plant for producing such a metal as zirconium uses relatively large quantities of chemicals which may be detrimental to the environment, if not carefully controlled. Chlorine, hydrochloric acid, nitric acid, sulfuric acid, hydrofluoric acid, ammonia, ammonium thiocyanate, and methyl isobutyl ketone are among those difficult to handle materials encountered in such an operation. Not only is disposal of waste products a potential evnironmental problem, containment of the reagents themselves present some unusual challenges. In many cases, a bootstrap approach is used wherein a reactive metal such as zirconium is found to possess the necessary corrosion resistant and noncontaminating properties highly desirable in equipment used for handling reagents or by-products encountered in its production.