eEnergy Group Regulatory News (EAAS)

26 Feb 2008 07:01

Alexander Mining PLC26 February 2008 Alexander Mining plc 26th February 2008 Significant developments in hydrometallurgical mineral processing technology with new HyperLeachTM process patent filed MetaLeach Limited formed to own AmmLeach(R) and HyperLeachTM intellectual property Alexander Mining plc ("Alexander", the "Company"), the AIM-listed mining andmineral processing technologies company announced today: • In discussion with over 25 companies, including international majors, about proprietary mineral processing technologies.• Eleven companies have signed confidentiality agreements, with more anticipated.• Seven companies have committed to metallurgical test work programmes.• MetaLeach Limited is the new name for Alexander's wholly owned mineral processing technology business.• HyperLeachTM is MetaLeach's new proprietary ambient temperature and pressure process for the leaching and extraction of base metals from sulphide ores and concentrates. MetaLeach now owns the intellectual property to two hydrometallurgicaltechnologies where provisional patents have been filed, namely AmmLeach(R) andHyperLeachTM. These can be summarised as follows: AmmLeach(R) A proprietary ammonia based process for the leaching and selective extraction of base metals from high acid consuming and complex ores under ambient (i.e.atmospheric) temperature and pressure conditions. Although initially developed for copper, the Company has also developed itsAmmLeach(R) process for the treatment of zinc oxide deposits. Test work resultsindicate a new solvent extraction and electro-winning (SX-EW) process forproducing high purity zinc metal at the mine. This process leaches common zincoxide minerals with very high extraction efficiencies and offers a potentiallyeconomic processing route for many zinc oxide deposits that are currentlyeconomically unviable. The Company believes that this technology will be of considerable commercialinterest to both mining companies and zinc metal producers because it has thepotential to be a highly competitive economic alternative to the processingtechnologies currently available. HyperLeachTM A proprietary ambient temperature and pressure process for the leaching andextraction of base metals from sulphide ores and concentrates. Martin Rosser, CEO, said:"With Alexander's exciting development of the HyperLeachTM process, whichcomplements its AmmLeach(R) technology, the creation and branding of MetaLeachLimited is an important step in our marketing efforts to provide innovative costeffective solutions to the international mining industry." "Because most base metal sulphides are processed to produce a concentrate at themine site, with the associated selling costs and payment terms involved, thereis considerable scope to do more on site processing to generate higher returnsfor mine owners. Indeed, in many cases miners may receive payment for as littleas 60% of the in situ metal content of the concentrate. We believe thatMetaLeach Limited, with its AmmLeach(R) and HyperLeachTM technologies, has atremendous opportunity to develop a substantial new business." MetaLeach Limited After its ongoing research and development work on processes for thehydrometallurgical extraction of base metals from ore deposits and concentrates,the Company has made significant progress. In order to maximise the commercialpotential, and more properly reflect the broadening range of its mineralprocessing technologies, the Company has renamed and rebranded its wholly ownedAmmLeach Limited subsidiary MetaLeach Limited. MetaLeach Limited has been formedto commercialise Alexander's proprietary new mineral processing technologiesthat have the potential to revolutionise the extraction processes for many basemetal deposits. In support of these marketing efforts, a new website reciprocally linked toAlexander's own, www.metaleach.com has been created. In addition, to its AmmLeach(R) process, MetaLeach Limited has developed asecond new innovative leaching technology - HyperLeachTM, for which aprovisional patent application has been made. HyperLeachTM has been developedfor the extraction of base metals from sulphide ores and concentrates. This ispotentially a major breakthrough for the global mining industry. HyperLeachTM process The HyperLeachTM process is a new proprietary process for the extraction of base metals, especially copper, zinc, nickel and cobalt from sulphidic ores andconcentrates and has been developed by Alexander's wholly owned technologysubsidiary company, MetaLeach Limited. The process utilises a chlorine basedoxidant to oxidise the sulphide, thereby allowing the metals to solubilise. Unlike previous chlorine based processes, HyperLeachTM does not require chlorinegas to operate; the oxidant can be generated on-site via industry standardchlor-alkali technology. A key feature of the HyperLeachTM process is that itoperates at ambient temperatures and pressure and is eminently suitable for heap leaching as well as tank leaching. HyperLeachTM technology is suitable for both low grade heap leaching and highergrade tank leaching; the choice is dictated by the grade and deposit economics.Polymetallic deposits can be readily handled using standard solvent extractionand solution purification techniques. Key Features • leaches base metal sulphides including chalcopyrite, bornite, chalcocite, millerite, pentlandite, pyrrhotite, violarite, sphalerite and enargite• ambient temperature• ambient pressure• heap leach or tank leaching• rapid kinetics• selective for sphalerite over galena• selective for nickel-sulphides over pyrite• low reagent consumptions Mining economics Currently, nearly all base metal sulphides are concentrated on-site using aphysical process such as gravity or flotation before being shipped off site to asmelter and refinery for further processing. The costs involved in selling anore concentrate include road transport, shipping, smelter and refinery chargesand can include penalty costs imposed by the smelter that are deducted from thepayable metal in the concentrate supplied. In addition in many situations mineowners may not be paid for valuable metal by-products contained in theconcentrate. Taken altogether these charges and costs can amount to as much as40% of the value of the contained metal produced from a mine. There is considerable scope to do more on-site processing to add value usinghydrometallurgy to generate higher returns for mine owners. The HyperLeachTMprocess has been developed to produce high value metal products on-site atcompetitive operating costs and relatively low capital costs. The technology and how it works The technology consists of three major stages; leaching, separation/concentration and recovery. The leaching can occur either in a heap or tank andinvolves contacting the ore/concentrate with a hypochlorite solution at anappropriate concentration. Solvent extraction is used to separate andconcentrate the metal(s) from solution whilst also changing from a mixedchloride/sulphate media to acid sulphate media, from which most metals can bedirectly electrowon using industry standard unit operations. One of the key benefits of the HyperLeachTM process is that, unlike some othertechnologies, it requires no special purpose built equipment, only the additionof an appropriate leaching circuit or leach pads and collection ponds. Potential applications The following metals and applications are particular targets for theHyperLeachTM process: • low grade nickel sulphide ores• nickel sulphide concentrates• nickel mattes• low grade copper sulphide ores• low grade native copper ores• copper flotation concentrates• arsenical copper ores• arsenical gold ores• gold bearing sulphides• concentrate cleaning. The use of HyperLeachTM for potential applications with platinum group metals(PGM's), molybdenum sulphides and uranium leaching is also currently beinginvestigated. Indicative costs Whilst still at an early stage, it is possible to give indicative operatingcosts for the HyperLeachTM process to produce various metals, these are shownbelow: +--------------------+--------------------------------------------+|Mineral | Range of HyperLeachTM operating costs || | US$/lb metal produced |+--------------------+--------------------------------------------+|Copper | 0.45-0.90 ||chalcopyrite CuFeS2 | |+--------------------+--------------------------------------------+|Nickel | 0.60-1.20 ||pentlandite (Ni,Fe) | ||9S8 | |+--------------------+--------------------------------------------+|Zinc | 0.40-0.80 ||sphalerite ZnS | |+--------------------+--------------------------------------------+ Nb: These indicative costs are based upon chlorine costs of between US$300-$600per tonne and power costs of between US$0.04-0.13 per KWh. For further information please contact: Martin Rosser Matt SutcliffeChief Executive Officer Executive ChairmanMobile: + 44 (0) 7770 865 341 Mobile: +44 (0) 7887 930 758 Alexander Mining plc1st Floor35 PiccadillyLondonW1J 0DW Tel: +44 (0) 20 7292 1300Fax: +44 (0) 20 7292 1313Email: mail@alexandermining.comWebsite: www.alexandermining.com Nominated Advisor and BrokerAlasdair Younie/John PriorArbuthnot Securities LimitedArbuthnot House20 Ropemaker StreetLondon EC2Y 9ARTel: +44 (0) 20 7012 2000 Public/Media RelationsTim BlackstoneBritton Financial PR62 Britton StreetLondon EC1M 5UYTel: +44 (0) 20 7251 2544Mobile: +44 (0) 7957 140 416 This information is provided by RNS The company news service from the London Stock Exchange