Injection processes: a metallurgist in two phases

摘要

Injection processes are key to a wide range of pyrometallurgical unit operations from converting to lance injection of particulates. These processes include 'simple' gas injection into liquids as well as multiphase flows when solids and/or liquids are part of the injected stream. This paper summarizes Keith's many contributions to the field covering all aspects of injection processes. His early work on the different injection regimes of bubbling and jetting, and the conditions determining the transition between the two, was critical to advancing our knowledge of these processes. Our understanding of metallurgical injection has evolved through an interplay of laboratory and industrial studies, and an interaction of academic and commercial research, for which Keith was an important catalyst. This paper attempts to detail the role he played in this area as he worked toward development of the technology both through measurements on existing systems and specially designed plant trials. Particularly noteworthy were his efforts in the area of copper converting. Just as injection speaks to a minimum of two phases, pyrometallurgy is itself made up of two somewhat immiscible phases: the ferrous and nonferrous industries. Keith recognized the two 'solitudes' and was in a special position to bridge the gap in technology. The use of high-pressure injection in the nonferrous industry was one idea for which he held out much potential. Our knowledge of injection processes has advanced substantially over the last thirty years, in no small part to the leadership of J.K. Brimacombe.