GeoBiotics, LLC has developed and patented several technologies for biooxidizing or bioleaching sulfide ores and concentrates in an engineered heap environment. The two principle technologies are the GEOCOAT® and GEOLEACH™ processes. Both technologies incorporate the patented HotHeap™ control philosophy to ensure optimum biological performance. The processes can best be described by the figure below:

GEOCOAT®

The GEOCOAT® technology offers a unique approach to the application of bacterial processing; combining the low capital and operating costs of heap leaching with the high recoveries obtained in agitated tank reactors. Both of which are well accepted processes in the minerals industry and are in commercial operation worldwide. In the GEOCOAT® process, sulfide flotation or gravity concentrate slurry is coated onto crushed and sized support rock which may be barren or may contain sulfide or oxide mineral values. The coated material is stacked on a lined pad for biooxidation. The process is applicable to the biooxidation of refractory sulfide gold concentrates and to the bioleaching of copper, nickel, cobalt, zinc, and polymetallic base metal concentrates. Mesophilic or thermophilic biological systems are used to catalyze the sulfide oxidation reactions. In the processing of chalcopyrite concentrates, the higher temperatures associated with the use of thermophile microorganisms have proven highly beneficial in increasing the rate and extent of copper leaching. In the processing of refractory gold sulfide concentrates, the GEOCOAT® process offers significant cost advantages over the established processes: roasting, pressure oxidation, and agitated tank biooxidation. In base metals operations, the GEOCOAT® process is particularly suited to the treatment of “dirty” concentrates, can reduce transport by allowing the on-site production of metal at remote deposits, and can take advantage of depletion of oxide reserves through the utilization of existing SX/EW equipment. The process is simple, robust, and ideally suited to operation in remote locations.

GEOLEACH™

The GEOLEACH™ technology is applicable for whole ore systems where the metals occur as sulfides. The driving force behind the GEOLEACH™ process is that most sulfide whole ore leaching systems have enough energy present in the sulfides to allow the heap to obtain very high temperatures but poor heat management prevents significant temperature rise. Without significant increase in temperatures beyond ambient within the heap, sulfide leaching kinetics are extremely slow and in the case of chalcopyrite extraction is limited by passivation. The GEOLEACH™ technology is designed to maximize heat conservation through careful control of aeration and irrigation rates. GEOLEACH™ has built on the best industry knowledge around the operation of bioleaching facilities and added to this the HotHeap™ control/operating philosophy. GEOLEACH™ is very similar to conventional whole ore acid heap leaching systems but with the addition of a system to maintain biological activity and maximize heat conservation. The process is simple, robust, and ideally suited to operation in remote locations.

Other Technologies

A wide variety of additional patented expertise form the framework of the GeoBiotics technology suite including high temperature bioleaching, toxin removal, HotHeap™, BioPro®, and a series of other complementary internal process focused around pretreatment, aeration, stacking and instrumentation.

HotHeap™ - a biological heap leach operating philosophy coupled with an instrumentation and control system that maximizes heat conservation and thus bioleaching kinetics.

BIOPRO® - an inoculation method for biological heap leaching systems. (licensed from Newmont)