MINING CHEMICALS
Back in 2020 , Protea Mining Chemicals , a member of the Omnia Group , announced it had become the first in its field – globally – to develop a solution to help copper and cobalt mines reduce product contamination ( improving metal purity levels ) and maximise throughput in the solvent extraction ( SX ) process .
This solution , which the company developed with its key principal , Innospec , took six years to establish and was carried out in partnership with chemicals manufacturers and copper and cobalt mining customers in the Democratic Republic of the Congo , Omnia said .
Close to four years after this announcement , IM caught up with Lefa Masiuana , GM of Protea Mining Chemicals , for an update .
IM : First off , can you explain the mechanics of how you are able to reduce product contamination and maximise throughput in the SX process ? Is this with some specially selected reagents ? LM : This is through the use of a speciality coagulant targeted to remove colloidal silica from the solution , which is the cause of many of the challenges seen in SX .
IM : Can you provide any numbers around what percentage improvements in product quality and throughput have been achieved ? What scale of test work did you carry out ? LM : This has been tested at various levels : lab scale , pilot plant , plant trials , etc and is being
The before photo on the left shows an emulsion formed with incomplete separation , and the after photo once Protea Mining Chemicals ’ Dehscofix ® SC12 has been added , showing elimination of the emulsion and excellent phase separation
used commercially at a number of operations . The percentage improvements depend on various factors and from site to site . We saw around a 15-20 % improvement in throughput as well an improvement in product quality , from 50 % on-spec product to 98 % on-spec product . Significant cost savings in the use of other reagents were introduced by reducing loss of key extractants .
IM : Is this solution now being applied on a commercial basis with DRC copper-cobalt producers ? Can you say what commercial results have been achieved ? LM : Yes , this is being applied at a number of mines in the DRC and now also in Zambia at a couple of operations . The results indicated above were from commercial applications . lead / zinc producer in the Asia Pacific region address the challenge related to high graphitic carbon in its feed and unforeseen concentrate quality issues caused by its incumbent reagent . By using Luproset D 1313 , the customer enhanced its metal recovery by 4 %, achieving a value of € 12 million ($ 12.9 million ) in financial gains , BASF said .
The company ’ s Luprofroth frothers are , meanwhile , being implemented for sulphidic and non-sulphidic applications across a variety of ores and processing conditions , with BASF highlighting success cases in copper and gold mines in the Americas and Asia Pacific , where its solutions were able to achieve higher recovery , reduce reagent consumption and enhance the EHS profile by implementing a product with lower toxicity and ecotoxicity , it said .
Outside of these launches , the company says it expects to advance further in the flotation segment with the expansion of its portfolio , with test work going on in multiple fields such as coarse phosphate , lithium and molybdenum flotation .
“ Additionally , we continue developing solutions that follow the transformation of the mining industry and meet the needs of new flotation equipment technologies ,” Stewart said .
On the hydrometallurgical front , BASF has several mines around the globe testing its LixTRA™ leach aid , a non-hazardous reagent , compatible with downstream solvent extraction and electrowinning processes that , BASF says , does not negatively affect microbial activity . LixTRA is primarily aimed at oxide and secondary sulphide ores , offering increased copper recovery and extraction kinetics . For primary sulphide ores , such as chalcopyrite , which are historically difficult to leach , LixTRA does improve extraction . “ However , we primarily see it as complementary to other embryonic chalcopyrite leaching technologies such as chloride leach , as its key role is to increase the contact between the ore and lixiviant , then in theory it will benefit all leaching processes ,” the company said .
Other ongoing developments from BASF include a proprietary extractant additive , marketed under the LIX ® HS trade name , which is nitration proof , more resistant to degradation and offers enhanced iron selectivity in SX-EW processes ; and the development of a more sustainable acid mist suppressant for the environmentally-challenged EW process .
Clariant ’ s solution to avoid the use of ‘ forever chemicals ’
Acidic mist in the electrowinning operations has long been a challenge in the copper industry and , until recently , the use of perfluoroalkyl compounds as acid mist suppressants was the most widely used solution , Clariant says .
The manufacture of these compounds is being phased out by major suppliers , as perfluoroalkyl compounds have been found in drinking water supplies , leading to multibillion dollar settlements with water utilities .
As electrowinning operators look for alternatives that are free of so-called “ forever chemicals ”, Clariant has developed a new line of acidic mist suppressants that do not contain fluorinated compounds .
Clariant ’ s FLOTICOR™ DC acid mist suppressants have been proven effective in plant operations on multiple continents , controlling the acid mist in electrowinning without affecting the cathode quality or causing phase separation issues in the solvent extraction process , the company claims .
IM
54 International Mining | MAY 2024