Metals and materials from deep sea nodules: an outlook for the future

Abstract

<title/>The global data on manganese reserves apparently indicate that there is no resource crunch. However, a large part of the terrestrial deposits (80%) do not meet the grade requirement for efficient production of high quality ferroalloys required for steel making. The marine mineral deposits, which have attracted the greatest interest as alternative exploitable source for this element, are the deep-sea manganese nodules. If efficient schemes for manganese recovery values are put in place, the marine deposits would rather be classified as manganese ores which would have remarkable advantages over terrestrial low grade deposits because of by product recovery of copper, nickel and cobalt. Specific processing schemes for production of manganese alloys and compounds are critically discussed in this overview. The production of high purity Cu, Ni and Co using solvent extraction has also been reviewed. Optimisation approaches for sea nodules processing schemes have been analysed. Various other potential applications of sea nodules have been brought out. The possibility of integration of the processing schemes with land based production processes are likely to render sea nodules as useful alternative sources for metals and other value added materials of the future.