We are able to supply cyanide in drums (50kg), boxes (1000kg) and sparge containers (+ / – 20 tonnes). The benefit of sparging is that the cyanide is dissolved directly from the bulk container on the mine and no handling of solid cyanide is required. Furthermore there are no packaging disposal problems on the mine.
Nowata supply a range of anionic, non-ionic and cationic flocculants from SNF Floerger who are world’s largest water soluble polymer manufacturer. We have Chemists and Metallurgists who are experienced in laboratory testwork and the scale-up of these results to plant operation. We have developed products which are unique to Nowata and are specifically manufactured by SNF for Nowata as a direct result of our testwork programmes. We also supply SNF’s range of “polyamine” and “polydadmac” coagulants.
Nowata personnel are actively involved in the manufacture and supply of flotation reagents. These can be conveniently divided into the following categories.
Collectors and Promoters
Nowata purchase various xanthates from manufacturers in both South Africa and the Far East. As well as the standard xanthate homologues of ethyl, propyl, butyl and amyl, Nowata supply mixed xanthates in conjunction with other collectors.
As well as xanthates which are still used as the primary collector in most mines we have a range of dithiophosphates, dithiocarbamates, xanthogen formates and xanthic esters. We have developed a customized range of blended products which have application in the gold, base metal and platinum industries and have been shown to give improved recoveries particularly where rapid oxidation may occur. These blended products have been shown to be capable of replacing both primary and secondary collectors.
We have a range of frother blends which utilize, alcohols, glycols and glycol ethers which can be supplemented using reagents having both frothing and collecting properties. As well as blending our own products we purchase MIBC and DMP from other manufacturers.
Nowata have assisted a local Ghanaian company (AfriChem) to develop a range of frothers for the West African market and these are being blended in Ghana.
We supply both Copper sulphate and Lead nitrate as activators. The former is used in gold and PGM circuits and the latter in stibnite flotation. We supply sodium hydrosulphide which is used to activate tarnished sulphides.
We have a range of guar based gangue depressants, toll manufactured to our specifications. These have been used in the depression of naturally hydrophobic gangue minerals in base and precious metal operations in Africa and Australasia. We also have access to a range of carboxymethylcellulose derivatives which have a similar action to the guar’s and can often be used interchangeably, the choice often depending on reagent cost.
Dust Control Agents
Lignosulphonate binder which efficiently supresses dust generation on haul roads and waste dumps. Non-toxic, environmentally friendly and easily applied.
Smelt House Chemicals
We supply the various chemicals required in the smelting of gold as part of our overall supply package. Typically borax, anhydrous and the decahydrate, sodium carbonate, sodium and potassium nitrate, silica and fluorspar are supplied.
In support of our range of performance chemicals, we supply many of the commodity chemicals required by the mining industry. Examples being, caustic soda, hydrochloric, nitric, sulphamic and sulphuric acids, quicklime and hydrated lime.
As an alternative to hydrogen peroxide or Caro’s acid a number of mines prefer to use sodium metabisulphite as the oxidant in the cyanide destruction process. This is used in conjunction with copper ions, supplied by the addition of copper sulphate. Some plants use hydrogen peroxide together with the sodium metabisulphite as a supplementary oxidant.
In conjunction with Solvay we can supply automatic dosing systems to feed from either IBC’s or ISO-containers and Caro’s acid units for cyanide destruction.
Nowata’s proprietary technology is licensed within Ghana for the manufacture of antiscalants for the West African mining industry.
These antiscalants are used in CIL and heap leach plants to control scaling. There are high temperature products for use in the elution circuit.
Most scale control is geared to calcium carbonate deposits, increasingly calcium sulphate scale is encountered in some operations where cyanide detoxification is accomplished using sodium metabisulphite. This is controlled by a specially formulated product.