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Manipueira, an extract solution from the cyanogenic bitter cassava plant to impact the future use of CN salts in LSM & ASM gold ore processing & in ASM tailings wastes remediation.
About
Manipueira Gold Recovery Technology Inc., (“MGRT”), a development Company has preliminary flow schematics in an interactive chart, following below, prototyping the world’s first sustainable precious metals manipueira leaching center (”Manipueira Center”) designed to use a low-cost extract solution from the cyanogenic bitter cassava plant known as manipueira (cassava wastewater), as a lixiviant (leaching agent) to recover gold from ore and toxic tailings wastes. The Company estimates the cost for engineering, implementation, remediation, and the conversion of a whole ore mercury amalgamation chilean processing center (“Chilean Center”) to a Manipueira Center will total USD $2.0 million inclusive of USD $150K due diligence costs including equipment, meetings, and site visits. Subsequent conversions are “estimated” to cost USD $1.25 million and to take 12 months. Strategically, the Company determined that, before approaching an owner of Chilean Center and more specifically, a center that leaches gold using the Merrill-Crowe gold precipitation process, it would be effective to demonstrate the use of manipueira with a less costly and less-time consuming whole ore mercury amalgamation chancha barrel processing center(“Chancha Center”), specially one that houses no tailings ponds. Using mercury to recover gold in these centers only recovers 20 – 30% of the liberated (free) ore gold in their slurry, and with the remainder of the ore gold being lost to tailings wastes after processing, The initiative is to provide an incentive in the form of an interest free loan to the owner to adopt the Company initiative and to form a joint venture partnership to remediate and the convert the partnerships Chancha Center to a “Manipueira Barrell Center” which will demonstrate 2 – 3 times more gold sustainably recovered wherein which the Company will proceed with the plans to promote our ESG driven climate action initiative throughout the mining district. Say goodbye to mercury, a deadly neurotoxin, used in artisanal small-scale mining (“ASM”) ore processing and cyanide salts used to recover gold in tailings wastes, and the use of cyanide salts in ASM and large-scale mining (“LSM”) leaching operations. Say hello to manipueira, nature’s safer lixiviant destined to impact the future of mercury and cyanide salts in the global LSM & ASM mining sectors.
Key Benefits
In 2021, global cassava production was estimated at 308 million tonnes with Africa’s total production being about 203 million tonnes (about 56% of world production), followed by Asia (84 million tonnes) and America with 26 million tonnes. Manipueira solution typically contains 267 mg/l (267 parts per million (“ppm”) of aqueous free cyanide and up to 600 mg/l in Brazilian bitter cassava, has a pH of 5.5, and represents 30 - 35% of the plant’s weight. It stinks when fermented, attracts insects, and is recklessly discarded directly into the environment by the flour manufacturers causing biodiversity destruction, creating human health threats, contaminating the soil and drinking water, and polluting the rivers. The annual discard of the cassava wastewater represents a global cyanide loss of an estimated 92 million tonnes. According to Nural Kuyucak and Ata Akcil 2013 publication; “the extraction processes of gold, silver, and various metals from ores consume 13 % or 143,000 of 1.1 million metric tons of hydrogen cyanide produced worldwide annually.” Ecuador’s cassava production in 2021 was 96,210 thousand tonnes “The symbiosis of artisanal ore processors and flour makers is a win-win situation to reduce mercury environmental pollution while mitigating an unintended consequence of harvesting the bitter cassava plant.” Marcello Veiga. Research spearheaded by Dr. Marcello Veiga, P.Eng., Professor Emeritus University of British Columbia, and Company Advisor is currently underway to biologically increase the free cyanide content to 1,000 mg/l. Typically, 100 – 110 ppm of CN is used to leach gold from ore.
Applications
Zaruma, one of Ecuador’s 5 UNESCO World Heritage sites located at 1,300 meters elevation in the Amazon Andes, is the world’s pinnacle source of deadly global atmospheric mercury air pollution .Forty-thousand residents of Ecuador’s Portovelo-Zaruma mining district including 10,000 impoverished local artisanal miners, all largely suspected of having undiagnosed mercury poisoning, from processing the local miners ore and ore from an additional 40,000 miners who transport their ore from neighboring mining districts for processing using mercury and to sell their dehydrated tailings wastes which the processing center owners recover gold leaching with cyanide salts. According to Adriana O. Gonçalves et al 2017 research publication, a 2015 survey of 20 of a 67 member local mining organization known as Aproplasmin whose members collectively own 68 of the 87 chilean ore and tailings processing centers situated along one square mile on the Calera and Amarillo riverbanks. 95% of these centers average 2 tonnes/month of cyanide use and 65% centers average 2.4 kg/month of mercury use. These centers are collectively responsible for the discharge of 1.9 million tonnes of toxic tailings wastes containing an estimated 222 kg of mercury and an estimated 2,033 tonnes of cyanide directly into the rivers annually, methylmercury at 100 times more potent than elemental mercury and with unknown biomagnification effects, and toxic mercury-cyanide highly bioavailable complexes all providing mobility for mercury. This toxic pollutant according to Bruce Marshall et al 2020 publication, “has resulted in high CN- contamination of the Puyango-Tumbes River downstream from the centers. Free CN- concentrations were high in river surface waters for 50 km below the processing plants, with the highest concentration 9088 times above the CCME (Canadian Council of Ministers of the Environment) standard of 5 μg/L and 1136 times above the 24-h LC50 concentration of 40 μg/L free CN- for some fish species”. This pollutant continues zigzagging throughout the Amazon polluting the rivers, contaminating the riverbanks, and drinking water, and killing all local biota to empty 350 KM west into the Pacific ocean to contaminate the fish we consume, especially Tuna where mercury/methylmercury bioaccumulates the most. These centers also release an estimated 303 kg of mercury to the atmosphere annually from the burning of the mercury-gold amalgams to recover the gold.