The Glycine Leaching Process is an environmentally benign hydrometallurgical process that will leach base and precious metal oxide, mixed oxide and sulphide ores.
Glycine is the simplest and cheapest amino acid, and is available in bulk in different grades. It is an environmentally safe and stable reagent and is biodegradable and easily metabolized in most living organisms.
It is selective on which metals it leaches, as shown in the following periodic table excerpt.
It is easily recovered and recycled. Flow sheet test work and modelling to date has shown that less than 5% Glycine loss can be expected. This means low reagent consumption costs for the major leaching reagent.
It is a simple process with “off the shelf” items of equipment required.
GlyCat™ is the application of Glycine with cyanide to mixed base metal and precious metal ores. The presence of copper minerals in with gold is known to lead to many challenges during the cyanidation of gold ores, such as high consumption of cyanide with low gold extraction and undesirable impacts on gold recovery during the downstream processes. GlyCat is a process to enhance the dissolution of gold and copper in gold/copper ores where glycine is used as a catalyst with cyanide in a cyanide starved leaching environment.
GlySlag™ is the application of Glycine to leach residual metals contained in slags, a byproduct of the smelting process. Typically these slags are stockpiled and in the case of copper slags can contain up to 1% copper in a form that does not respond well to traditional processing. Most of these slags are eventually either used for other industrial and construction materials or in some cases reprocessed through conventional flotation plants with low recovery rates.
GlyMine™ is the application of Glycine as a Lixivant in applications where leaching of valuable metals can be carried out by circulating the lixivant through bore holes into a permeable or semi-permeable rockmass (in situ) or directly on broken ore (in place) with minimal handling and size reduction. Glycine is attractive over other known lixivants due to its low toxicity and biodegradable nature.
GlySmelt™ is the application of Glycine as a method to leach concentrates.
It offers opportunity to improve on suboptimal precious and base metals recovery for existing plants that use flotation. These plants often run with lower mass pulls (% of overall feed reporting to overall concentrate), with subsequent loss in recovery, just to make a target grade for shipping.
Gold recoveries to concentrate are also often sacrificed to make a threshold smelter grade.
CVL is a mechanical leaching system developed by Innovat Mineral Processing Solutions. The basic concept is to provide, by means of an elevated head tank, intermittent fluidisation of the ore in a swimming pool-like vat. This intermittent fluidisation provides high intensity leaching, and through hydraulic means, move the ore through the vat continuously.
MPS has been granted an exclusive agency that covers the Australasian region by its Canadian developer, Innovat Mineral Processing Solutions. MPS also has non-exclusive rights in other parts of the world that involves MPS undertaking amenability test work and technical support to other agents.
The technology has been piloted in North America for both copper and gold ores and a demonstration plant built and operated in Costa Rica in early 2000.