Minerais : Exploration et Exploitation sous marine

[energy_isere]

Le serpent de mer de l'exploitation des nodules polymétallique revient !
la compagnie Allseas va utiliser un bateau de forage pétrolier de Petrobras et le transformer d'ici milieu 2021 en bateau de capture de nodules polymétalliques.

Allseas Drillship to Pursue Deep-Sea Metals

by Matthew V. Veazey|Rigzone Staff|Thursday, March 05, 2020

Allseas Group S.A. reported this week that it has acquired the Vitoria 10000, a former ultra-deepwater drillship previously owned by Petrobras, to re-configure for an emerging business: recovering deep-sea “nodules” containing high-grades of metals such as nickel, manganese, copper and cobalt.

The metals within the seafloor-based rocks are key ingredients for building electric vehicle batteries and renewable energy technologies. Moreover, Allseas stated that sourcing metals from the deep sea reduces environmental and social impacts.

“Allseas is excited to be involved in the exploration of the deep ocean for these important metals,” Edward Heerema, founder and president of Allseas, commented in a written statement from his firm. “Deep-sea polymetallic nodule collection represents a new frontier and a new exciting chapter in Allseas’ history. With our offshore expertise and innovative capacity, we can develop creative technical solutions for this new industry.”

Allseas, partnering with the minerals exploration and development firm DeepGreen Metals Inc., stated that will convert Vitoria 10000 into a “polymetallic nodule collection vessel.” The drillship – built in 2010 – will be fitted will a deep-sea mineral collection system to recover polymetallic nodules from the ocean floor in an environmentally responsible manner and transfer them to the surface for transport to the shore, added Allseas, which is engineering the recovery technology. Onshore, DeepGreen will process the nodules using a metallurgical flowsheet that it developed.

Citing the vessel’s 748-foot (228-meter) length, 138-foot (42-meter) width and ability to accommodate 200 people, Allseas pointed out the ship is well-suited for modifications enabling seaborne deployment of the 2.8-mile (4.5-kilometer)-long riser that it is developing.

“To have partners like Allseas bring their engineering excellence and passion to help get this industry started makes us, and the industry, very fortunate,” remarked DeepGreen Chairman and CEO Gerard Barron. “The green transition is going to require hundreds of millions of tonnes of nickel, copper and cobalt, and our research shows that ocean polymetallic nodules could provide society with these critical minerals at a fraction of the environmental and social impacts associated with land-based extraction.”

Allseas noted that DeepGreen is participating in an unprecedented integrated surface-to-seabed research program aimed at improving understanding of collecting nodules from the ocean floor. The company added the research effort will develop new scientific knowledge about the Pacific Ocean and help it to design nodule collection technologies that minimize environmental impacts.

An Allseas spokesperson told Rigzone that the shipyard where the conversion will take place has not been confirmed. The company stated that it expects the re-configured vessel to be ready for initial nodule collection tests by mid-2021.

https://www.rigzone.com/news/allseas_dr ... 9-article/

https://lemarin.ouest-france.fr/secteur ... es-nodules

[energy_isere]

Suite du post au dessus.

DeepGreen to make run for battery metals from seafloor

Cecilia Jamasmie | April 7, 2020


The former ultra-deepwater drill ship “Vitoria 10000” is being converted to a polymetallic nodule collection vessel. (Image courtesy of DeepGreen.)

DeepGreen Metals, a Canadian start-up planning to extract cobalt and other battery metals from the seafloor, has added a new area to its seabed portfolio, which it believes could potentially help it solve the bottleneck supply of critical battery metals needed for the world’s green energy transition.

The strategic acquisition of Tonga Offshore Mining Limited (TOML), announced Tuesday, gives the Vancouver-based company exploration rights to a third area inside the Clarion-Clipperton Zone (CCZ) in the Pacific Ocean.

The 4,000-kilometre swath of ocean, stretching from Hawaii to Mexico, is known for containing enough nickel, copper, cobalt and manganese to build over 250 million electric vehicle batteries.

The new license covers 74,713 km2 of CCZ seabed, with an inferred resource of 756 million wet tonnes of polymetallic nodules — potato-sized metals-rich rocks that lie in a shallow layer of mud on the seafloor.

DeepGreen believes that producing critical battery metals from polymetallic nodules has the potential to eliminate or dramatically reduce most of the environmental and social impacts associated with traditional mining.

“We believe now more than ever that the world needs to work together to find solutions to address climate change,” the company’s CEO and chairman, Gerard Barron, said in the media release.

The news follows DeepGreen’s offshore engineering partner Allseas’ recent acquisition of a former ultra-deepwater drill ship for conversion to a polymetallic nodule collection vessel.

The vessel is being converted to accommodate a pilot nodule collection system. After the nodules have been collected and taken to shore they will be processed using a metallurgical flowsheet developed by DeepGreen.

Unlike other seafloor miners, the company doesn’t want to drill, blast or dig the bottom of the ocean. Its main goal is to scoop up small metallic rocks located thousands of metres below the surface in the Pacific.

The deep sea, accounting for more than half the world’s surface, contains more cobalt, nickel, copper, manganese and rare earth metals than all land reserves combined, according to the US Geological Survey.

...................

https://www.mining.com/deepgreen-makes- ... -seafloor/

[energy_isere]

Encore une autre boite interessée à ramasser des nodules polymétalliques, une startup au Canada : DeepGreen Metals

lire https://www.mining.com/extracting-batte ... ing-study/

[energy_isere]

Le robot Patania II extrait du métal à 4 500 mètres de profondeur

Publié le 23/04/2021 lemarin

Le robot Patania II de GSR (Global sea mineral resources), filiale de Deme spécialisée dans l’exploration minière offshore, a réussi à extraire des nodules polymétalliques à une profondeur de 4 500 mètres, « une première historique », a salué le 22 avril le groupe belge.

Ces nodules, des concrétions rocheuses de la taille d’une pomme de terre riches en nickel, cobalt, manganèse ou encore en cuivre, ont été extraits dans la zone de fracture de Clarion-Clipperton (CCZ), entre le Mexique et Hawaï.

L’essai a été mené en association avec le projet scientifique MiningImpact, qui réunit 29 instituts européens (parmi lesquels l’Ifremer), aux côtés du titulaire du contrat d’exploration, l’Institut fédéral allemand des géosciences et des ressources naturelles (BGR).

S’il montre la possibilité d’extraire des nodules métalliques dans les grands fonds marins, ce test doit aussi aider à en mesurer l’impact environnemental, que dénoncent déjà les ONG de protection de l’environnement. Objectifs : comprendre les effets directs de la collecte mais aussi ceux du panache sédimentaire engendré par l’opération, et étudier la perte de biodiversité associée.

D’autres plongées du Patania II sont prévues les prochaines semaines dans les zones contractuelles belges et allemandes de la CCZ. En 2024, le robot devrait être utilisé dans le cadre d’une autre mission pour tester la remontée des minerais par une colonne ascendante.



Robot à chenilles de 25 tonnes, le Patania II a été déployé à partir d’un navire via un câble de levage et de communication bidirectionnelle de 5 km. Il a passé 50 heures sur les fonds marins de la zone de fracture de Clarion-Clipperton. (Photo : Deme)

https://lemarin.ouest-france.fr/secteur ... -metres-de

[energy_isere]

suite du post au dessus , l'engin Patania II de 25 tonnes s'est retrouvé en difficulté à plusieurs milliers de m de profondeur.

Deep-sea mining tests resume as lost robot rescued

Cecilia Jamasmie | April 30, 2021



Belgium’s Global Sea Mineral Resources (GSR) resume tests on Friday that could lead to the mining of battery minerals from the Pacific Ocean floor after it managed to recover a robot stranded at a depth of thousands of metres.

The company reported Wednesday that its Patania II, a 25-tonne mining robot prototype, had uncoupled from a 5km-long (3.1 miles) cable connecting it to the surface.

The unit of Belgium’s DEME Group is with a group of European scientists to determine the environmental impacts of deep-sea mining. They are working on GSR’s concession in the Clarion Clipperton Zone.
........
Before this week’s incident, Patania II had had collected potato-sized rocks called “polymetallic nodules”, which are rich in manganese, cobalt nickel and rare earths from the seabed.
........

https://www.mining.com/deep-sea-mining- ... t-rescued/

[energy_isere]

suite de ce post du 26 avril 2020 http://www.oleocene.org/phpBB3/viewtopi ... 5#p2301695

DeepGreen Metals lance une nouvelle campagne de recherche de nodules polymétalliques dans la zone de Clarion Clipperton

DeepGreen Metals launches new deep-sea research on battery metals

09 Jul 2021 (Last Updated July 9th, 2021

The Environmental Expedition 4E research campaign will be conducted in the Clarion Clipperton Zone in the Pacific Ocean.


Canadian company DeepGreen Metals has launched a new deep-sea research campaign to meet the global demand for nickel and other battery metals.

The Environmental Expedition 4E research campaign will be conducted within the NORI-D contract area of the Clarion Clipperton Zone (CCZ) in the Pacific Ocean.

It follows the successful completion of the Environmental Expedition 5D research project on deep-sea food chains, biodiversity, geochemistry, and nutrient cycles in the site.

The two expeditions form part of a multi-year, $75m deep-sea research programme.

This programme is intended to establish an environmental baseline and assess the potential impacts of operations proposed by DeepGreen to source critical battery minerals from seafloor polymetallic nodules.
........

https://www.mining-technology.com/news/ ... ry-metals/

[energy_isere]

Des défenseurs de l'environnement appellent à un moratoire sur l'exploitation minière en eaux profondes

REUTERS•09/09/2021

Des responsables environnementaux et des militants ont appelé à un moratoire mondial sur l'exploitation minière en eaux profondes et sur l'octroi de nouveaux contrats d'exploration, à moins que les écosystèmes marins ne puissent être protégés efficacement.

Des milliers de défenseurs de l'environnement, de scientifiques et de diplomates ont voté mercredi en faveur du moratoire lors de la conférence de l'Union internationale pour la conservation de la nature (UICN) qui se déroule cette semaine à Marseille.

L'exploitation minière en eaux profondes utilise des machines lourdes afin d'extraire du fond de l'océan du cobalt, du manganèse et d'autres métaux rares utilisés dans l'élaboration de batteries.

L'UICN a déclaré dans un communiqué prendre acte des craintes selon lesquelles "la perte de biodiversité sera inévitable si l'exploitation minière en eaux profondes est autorisée, que cette perte sera probablement permanente à l'échelle humaine et que ses conséquences sur le fonctionnement des écosystèmes océaniques sont inconnues".

Pour l'instant, seule une infime partie du plancher océanique a été exploré et la grande majorité des espèces vivant en eaux profondes reste inconnue, ont dit les scientifiques.

"Permettre l'exploration minière en eaux profondes signifierait que ces eaux seraient exploitées avant d'être explorées", a indiqué à Reuters Edith Widder, une biologiste marine.

https://www.boursorama.com/actualite-ec ... 97eb59b9b4

[energy_isere]

Le retour des nodules polymétalliques ?

Could Sucking Up the Seafloor Solve Battery Shortage? The Metals Company wants to try, but opposition is fierce

PRACHI PATEL 13 SEP 2021

Reeling from a crushing shortage of semiconductor chips for vehicles, carmakers also face another looming crisis: producing enough batteries to drive the global pivot towards electric vehicles.

The supply of metals like cobalt, copper, lithium, and nickel needed for batteries is already shaky, and soaring demand for the hundreds of millions of batteries in the coming decades is likely to trigger shortage and high prices.

Some companies want to harvest metallic treasures from the sea. Strewn across large swaths of ocean plains some 5,000 meters deep are potato-like lumps called polymetallic nodules rich in metals and rare-earth elements critical for batteries and electronics. Nodules in the Clarion-Clipperton Zone (CCZ), which stretches between Mexico and Hawaii, are estimated to contain more cobalt and nickel than there are in deposits on land.

The Metals Company (previously DeepGreen Metals) in Vancouver expects to be the first to commercially produce metals from these nodules by 2024. And CEO Gerard Barron is confident they can do this without harming critical subsea ecosystems.

The nodules sit on top of the seafloor, so there is no drilling or digging needed. The company's robotic collector will inch along the seafloor, shooting out jets of seawater at the nodules, gently dislodging and suctioning them up. "It's like picking up golf balls on a driving range," says CFO Craig Shesky.

A ship will take the nodules to an onshore processing plant, where they will be smelted to get nickel sulfate, cobalt sulfate, copper and manganese. Texas is top of The Metals Company's list for the processing plant given the state's ports and access to cheap renewables. "We are committed to turning those rocks into metal using renewable power and with zero solid waste," Shesky says.


Agencies from seventeen nations have exploration contracts in the CCZ from the International Seabed Authority. The Metals Company has teamed up with three of those, from the tiny Pacific island nations of Kiribati, Nauru and Tonga, to access 150,000 square kilometers that, Shesky says, "have sufficient copper, nickel and cobalt to electrify the world's vehicle fleet several times over."

Land-based mining is already fraught with environmental destruction, emissions, human rights abuses, and mountains of waste, as well as precarious global supply chains. The Democratic Republic of Congo produces 70 percent of the world's cobalt, and most of the world's nickel sits under Indonesian rainforests. China processes about 80 percent of battery raw materials, creating a chokehold on global supplies. And with much of the world's high-grade resources already spent, companies have turned to low-grade mining resources that produce more waste and emissions.

"There will be a nickel deficit of 40 percent by the end of decade, even higher than copper," Shesky says. "We don't want to have happen with EVs what happened with the semiconductor shortage this year. The question is where should you go to get that metal? Let's go to the desert of the sea, the deep-sea abyssal plains, the parts of the world with least life as opposed to most life like the rainforest. There is 1500 times less life per square meter in these areas than in rainforests."

But while they might have low biomass, they also have astounding biodiversity. Craig Smith, an oceanography professor at the University of Hawaii at Manoa, who has led seven research expeditions to the CCZ. Deep-sea plains are sensitive, pristine ecosystems untouched by humans and their value is hard to assess. "Most of the species we bring up during these studies are new to science. We actually think it's a biodiversity hotspot."

So ocean mining could hurt, maybe annihilate, species we don't even know about yet, Smith says. Sediment plumes that the mining zones create could affect creatures living hundreds of kilometers away. And the nodules themselves are habitat to thousands of microorganisms. "It's not possible to mine polymetallic nodules from the seafloor on a commercial scale without causing substantial ecological damage over tens of thousands of kilometers," he says.

Shesky points out though, that 70 percent of the life in these regions is bacteria, as opposed to the diversity found in the rainforest. A recent study by mechanical engineers at MIT has shown that the detrimental impacts of sediment plumes generated by collector vehicles and by the water-sediment mixture returned into the sea from ships after separating the nodules might be exaggerated. The sediments settle down or dilute back to background levels quickly. Another study has shown that producing metals from nodules would create a tenth of the carbon dioxide emissions as that from land ores.

Even so, there's a lot of opposition to mining the deep-sea floor for resources. BMW, Google, Samsung, and Volvo have all said they will not buy metals mined from such sources until the environmental impacts are better understood. The companies have all signed a World Wildlife Fund moratorium to that effect.

As an extra precaution to ensure oversight and minimal disruption to these deep-ocean residents, The Metals Company will use drones and subsea sensors to monitor nodule-collection in real-time and beam it to stakeholders and regulators. "If there is impact to creature that we didn't anticipate, we can change our plan," he says.

The company last September awarded University of Hawaii at Manoa marine biologist Jeff Drazen US $2.9 million to assess the impacts of deep-sea mining in the CCZ.

https://spectrum.ieee.org/mine-ocean-ba ... l-shortage

[alga]

...ça Cousteau en parlait déjà dans les années 70. Une vraie catastrophe écologique en perspective d'autant qu'elle est n'est pas sous les regards.

[energy_isere]

Deep sea mining : le « Hidden Gem » se prépare pour des essais mi-2022

Publié le 05/11/2021

Allseas a dévoilé le 5 novembre les opérations en cours dans le cadre de la réalisation, à Rotterdam, du navire d’exploitation minière par grands fonds Hidden Gem.



installation du système de déploiement du collecteur de nodules, fourni par le spécialiste des équipements offshore Remazel engineering, sur le « Hidden Gem ». (Photo : Allseas)

https://lemarin.ouest-france.fr/secteur ... is-mi-2022

[energy_isere]

suite de ce post du 26 avril 2020 viewtopic.php?p=2301695#p2301695

The Metals Company (ex Deep Green Metals ) signe un MoU avec Epsilon Carbon pour une future usine de traitement des nodules polymétalliques en Inde.

The Metals Company signs MoU for PFS on world’s first deep-sea nodule processing plant

Staff Writer | March 17, 2022 |

The Metals Company (NASDAQ: TMC), formerly Deep Green Metals, an explorer of lower-impact battery metals from seafloor polymetallic nodules, announced Thursday that it has signed a non-binding Memorandum of Understanding with Epsilon Carbon to complete a pre-feasibility study for a commercial-scale deep-sea nodule processing plant in India called Project Zero Plant.


The company said targeted production capacity is more than 30,000 tonnes per annum (TPA) of an intermediate nickel-copper-cobalt matte product used for active cathode material (CAM) for Nickel Manganese Cobalt (NMC) and other nickel-rich cathode chemistries for lithium-ion batteries and more than 750,000 TPA of manganese silicate by-product expected to be used in manganese alloy production for the steel industry.

Mining international waters is in the spotlight as companies and countries are looking at minerals concentrated on the ocean floor that can be used in batteries for smart phones and electric vehicles. Last year, the company said the nodule resource is now estimated at four megatons (Mt) measured, 341Mt indicated and 11Mt inferred mineral resources.

In January, TMC announced the completion of its latest offshore research campaign, Environmental Expedition 5E, a targeted sampling campaign of both benthic and pelagic fauna with wider investigations to characterize ecosystem function on the abyssal seafloor.

The completion of the six-week expedition — the company’s fifth environmental campaign in the last twelve months — marked the latest offshore campaign required to develop an environmental baseline of the proposed operating environment in the Clarion Clipperton Zone (CCZ) of the Pacific Ocean and characterize the potential impacts of its proposed nodule collection operations to source critical battery metals from deep-sea polymetallic nodules.

The polymetallic nodule fields in the CCZ of the Pacific represent the largest known, undeveloped nickel resource on the planet. A DeepGreen-commissioned white paper found that nodules under exploration contracts in the CCZ contain more than enough battery metals to power one billion EVs and with a fraction of the social and environmental impacts when compared to land-based ores.

Environmentalists have called for a ban on deep-seabed mining that would extract resources including copper, cobalt, nickel, zinc, lithium, and rare earth elements from nodules on the ocean floor.

TMC said in Thursday’s release that through its subsidiaries, it intends to supply polymetallic nodules and onshore processing expertise while Epsilon Carbon intends to finance, engineer, permit, build and operate the Project Zero Plant. TMC has shared with Epsilon Carbon the near-zero solid waste processing flowsheet developed with Canadian technology and engineering firms between 2018 and 2021 and technical results from a pilot plant program completed in 2021 at FLSmidth’s facilities in Whitehall, Pennsylvania and at eXpert Processing Solutions’ (XPS) facilities in Sudbury, Ontario.

Epsilon Carbon intends to deliver a pre-feasibility report for a plant in India powered by renewables and with the targeted processing capacity of 1.3 million tonnes per annum (Mtpa) of wet nodules and production start in time to receive nodules collected from NORI-D area starting around Q4 2024, provided that TMC’s subsidiary NORI secures an exploitation contract from the International Seabed Authority.

The companies said they expect to enter a binding Heads of Terms for construction and operations of Project Zero Plant by September 30, 2022.

Safety, environmental and social impacts
“Over the last three years, we have engaged with many parties and visited plants around the world in search of the right onshore partners,” TMC CEO Gerard Barron said in the media release. “In Epsilon Carbon, we have found a rare mix: a proven operational execution track record in anode materials, a 21st century approach to industrial development grounded in making use of waste products, deep care about safety, environmental and social impacts, and an entrepreneurial ambition to develop cathode precursor materials.”

Barron said that Prime Minister Modi’s allocation last year of $600 million for India’s Deep Ocean Mission and the development of a polymetallic nodule collection system shows the country’s commitment to this new, abundant, secure, lower-cost and lower-ESG-impact potential source of critical metals.

“Having developed technology to tap an unconventional source of graphite — a waste stream from steel manufacturing — we are rapidly growing our anode materials business in India and…our strategy is to expand into cathode materials by 2024,” said Vikram Handa, founder of Epsilon Carbon.

“TMC’s polymetallic nodule resource struck us as a game-changing opportunity to tap another unconventional resource with several intrinsic properties that potentially allow us to develop a cathode precursor materials business with a much lower environmental and social impact. We have started with a PFR for a relatively small-scale plant but we believe that the scale of TMC’s resource has the potential to turn India into a significant supplier of critical minerals for battery and steel industries.”

https://www.mining.com/the-metals-compa ... ing-plant/

[energy_isere]

J'avais raté ça en 2021, la constitution de The Metals Company à partir de DeepGreen et de SOAC :

The Metals Company was founded in 2021 through the merger of DeepGreen and the Sustainable Opportunities Acquisition Corporation (NYSE: SOAC), to scale our nodule collecting and onshore processing systems.

We produce metals from polymetallic rocks to power electric vehicles. For over a decade, we’ve been exploring the planet’s largest known deposit of battery-grade metals: nodules on the seafloor of the Clarion Clipperton Zone in the Pacific Ocean. During this time, our onshore team has developed and successfully run a metallurgical process to derive key battery metals from these remarkable rocks while generating zero solid processing waste.

Our team is made up of scientists, environmentalists, engineers, architects, and business leaders who see the climate crisis as the biggest challenge of our time. Electric vehicles and renewable energy are a key part of the solution, but scaling these technologies will require hundreds of millions of tons of new metals. Polymetallic nodules represent the cleanest source of battery grade metals on the planet and the best path forward.

sur le site de cette sociéte https://metals.co/company/

[energy_isere]

FRANCE CULTURE DIFFUSÉ LE 06/04/2022
Exploitations minières sous-marines : on n’a pas fini de creuser !
Réécouter Exploitations minières sous-marines : on n’a pas fini de creuser !
ÉCOUTER (58 MIN) https://www.franceculture.fr/emissions/ ... de-creuser

À retrouver dans l'émission
LA MÉTHODE SCIENTIFIQUE par Nicolas Martin

Quelles sont les richesses minières cachées au plus profond de l'océan ? Quel est le contexte historique de l’exploration et de l’exploitation minière sous-marine ? Pourquoi l'exploitation des métaux revient-elle sur le devant de la scène ? Que sait-on de la biodiversité abritée dans ces fonds ?

D’après un rapport remis au gouvernement au mois de janvier dernier, en 2030, l’Europe ne produira pas plus de 30% de ses besoins en minerais stratégiques pour les batteries électriques de la transition énergétique, tels que le lithium, le cobalt ou le nickel.

Cette pénurie annoncée a pour effet d’aiguiser les appétits sur les ressources abondantes qui se trouvent sur les grands fonds marins. Si pour l’heure, les rares tentatives d’exploitation de ces ressources se sont conclues par des échecs, combien de temps cela sera-t-il encore le cas ? Pour l’heure, le temps est encore à l’exploration, assurait le chef de l’Etat au One Ocean Summit, mais d’exploration à exploitation il n’y a qu’un pas…

"Exploitations minières sous-marines : on n’a pas fini de creuser !" c’est le programme extracteur qui est le nôtre pour l’heure qui vient. Bienvenue dans "La Méthode Scientifique" !

[energy_isere]

Dans le podcast au dessus il est question dans les océans des
- nodules
- sulfures hydrauthermaux
et aussi de ceci que je ne connaissais pas : les encroutements.

aprés une petite recherche je trouve :
https://gresea.be/Des-metaux-au-fond-de ... onvoitises

Les encroutements cobaltifères et platinoïdes

On les retrouve dans tous les océans principalement sur des sites où le courant est fort et la sédimentation faible - c’est à dire que les sédiments n’ont pas recouvert le fond malgré les millions d’années écoulées. Ces encroutements se retrouvent généralement sur les reliefs océaniques (monts sous-marins, alignements volcaniques) entre 400 et 4000 m de profondeur. Ces sites représentent 1,7% de la superficie des océans soit environ 6,35 millions de km2. Les encroutements sont d’une épaisseur allant de quelques centimètres à 25 cm. Ils ont suscité un regain d’intérêt ces dernières années du fait de la présence de terres rares, cobalt et platine dans des concentrations plus fortes que les nodules polymétalliques et que les gisements terrestres. Là encore, les estimations semblent montrer que les ressources en thallium seraient 2000 fois plus élevées, celles en cobalt 4 fois plus élevées et celles en tellure 9 fois plus élevées que la totalité des réserves terrestres exploitables.

Les dépôts connus les plus "prometteurs" se trouvent dans le Pacifique Nord. La connaissance des processus naturels de formation de ces encroutements demeure encore incomplète tout comme la répartition des sites et l’épaisseur des encroutements, qui demeurent encore les moins bien étudiés des différents types de minéralisations. La valeur de ces gisements pourrait atteindre entre 500 et 1300$ la tonne au prix de 2010 [8].

[energy_isere]

suite de ce post du 5 nov 2021 : viewtopic.php?p=2329859#p2329859

TMC et Allseas testent leur collecteur de nodules par 2 500 mètres d’eau

Publié le 06/05/2022

Le collecteur de nodules polymétalliques conçu par Allseas a pour la première fois été testé par grandes profondeurs d’eau, a annoncé le 5 mai la start-up minière canadienne The metals company (TMC).

L’engin a été déployé à partir du navire d’exploitation minière par grands fonds Hidden Gem par 2 470 mètres d’eau, dans l’Atlantique. C’était « la première fois que le véhicule était soumis à des pressions et températures de l’offshore ultra-profond », a souligné TMC. Il s’est déplacé sur un peu plus d’un kilomètre sur le fond marin, ce qui a permis de tester ses pompes et fonctions de mobilité.

Prochaine étape, prévue cette année : des essais sur 8 km2 dans la zone du contrat NORI-D de la région de Clarion Clipperton, dans le Pacifique. Les données d’impact environnemental recueillies durant ces tests seront « à la base de la demande de contrat d’exploitation de Nori (NDLR : Nauru ocean resources inc), filiale à 100 % de TMC », auprès de l’autorité internationale des fonds marins, a expliqué The metals company.

En mars, l’engin avait été mis à l’eau dans le port de Rotterdam, où a été réalisé le Hidden Gem sur la base d’un navire de forage. Il avait ensuite été testé le même mois en eaux peu profondes dans les eaux néerlandaises.



Le collecteur de nodules polymétalliques conçu par Allseas a été déployé dans l’Atlantique à partir du « Hidden Gem ». (Photo : The metals company)

https://lemarin.ouest-france.fr/secteur ... 500-metres