Skorpion Zinc


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Sulphuric Acid Plant Specifications

Acid Plant Database September 17, 2025

Owner	Skorpion Zinc
Location	Situated 25 km north of Rosh Pinah in southern Namibia
Background	December 2010 - Vedanta Resources acquires Skorpion Zinc
Website	www.skorpionzinc.com.na
Plant	-
Coordinates*	27° 49' 31" S, 16° 36' 58" E
Type of Plant	Sulphur Burning
Gas Source	Elemental Sulphur
Plant Capacity	1150 MTPD
SA/DA	3/2 DA
Status	Operating
Year Built	2003 2020 - Care and Maintenance 2026 - Restart?
Technology	MECS
Contractor	Grinaker LTA (now Aveng E+PC)
Remarks	The sulphuric acid plant is a sulphur burning plant, producing two types of acid i.e. industrial and chemically pure acid. The waste heat generated from the acid plant is used to produce steam and keep the Refinery at temperature. There are also two 14MW electrode boilers to produce steam if the acid plant is down at any time.
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General	Skorpion Zinc is a world-first in zinc extraction and production. We produce 150,000 tons of special high grade (SHG) zinc per annum, which is shipped to our world-wide markets through the southern port of Luderitz .The Skorpion Zinc Mine and Refinery is a green field development. Skorpion Zinc has progressed from exploration though various project development stages to become a full-scale mining and refining operation. Although the Skorpion Zinc ore body was first discovered in the seventies, the deposit was not mined at that time as there were metallurgical problems associated with the treatment of the unconventional ore, and the ore body itself was considered too small to be economic in markets prevailing at the time. Reunion Mining Plc entered into an agreement with the Anglo American Corporation in 1997, in terms of which they could earn a percentage interest in the deposit for conducting further drilling, geological work and producing a "bankable" study to develop a mine by September 2000. Reunion did this work, solved the metallurgical problems, piloted the process and produced the bankable study by the end of 1998. The ore body delineated by Reunion Mining drilling comprised 19,5 million tonnes of ore at an average zinc grade of 10,1%. In 1999 the offshore arm of Anglo American, Minorco, purchased the entire shareholding of Reunion Mining plc to obtain 100% Anglo ownership of the Skorpion deposit. In the same year Anglo merged with Minorco and the resulting company was listed in London as Anglo American plc. Anglo American Plc (AA plc) then bought Reunion Mining's interest in the ore body and, following additional drilling and bulk sampling for a pilot plant, the go-ahead for the project was approved by the board of AA plc in September 2000 at a capital cost of US$454 million. Construction of the world class Skorpion Zinc mine and refinery commenced in January 2001.
Reference	-
News	September 17, 2025 - Vedanta Zinc International has announced plans to bring the sulphuric acid plant at the Skorpion Zinc Mine and Refinery back into production, with recommissioning scheduled for completion within the next four to six months. The announcement marks the first significant development at Skorpion since the mine was placed on care and maintenance in 2020. The sulphuric acid plant, originally constructed in the early 2000s, is an integral part of Skorpion’s zinc refinery complex located near Rosh Pinah in southern Namibia. Its role is to capture sulphur dioxide gases released during the roasting of zinc ore and convert them into sulphuric acid. By restarting the plant, Vedanta will not only reduce harmful emissions but also produce a high-value industrial product that has significant demand in Namibia and across the region. Once operational, the refurbished facility is expected to produce approximately 1 000 tonnes of sulphuric acid per day at a concentration of 98%, making it suitable for a wide range of industrial and metallurgical applications. This scale of production will re-establish Skorpion as an essential supplier of acid to Namibian industries and to regional markets. Vedanta is framing the recommissioning of the plant as both an environmental and economic initiative. By capturing sulphur dioxide emissions and converting it into a usable product, the company will minimise atmospheric pollution and support Namibia’s broader ecological commitments. At the same time, the production of sulphuric acid will generate revenues and potentially create employment opportunities for skilled workers during the refurbishment and operational phases. Vedanta noted that it has already issued a call for Expressions of Interest from companies interested in long-term off-take agreements. These agreements will cover both the supply of sulphuric acid and the logistics arrangements required to move product from the Skorpion site to customers. Deliveries will be made on an ex-works basis, which places responsibility for transport and distribution on the buyer once the product leaves the plant. “The initiative reflects our commitment to building strategic partnerships that create sustainable value. We invite companies with the required technical and logistical capabilities to submit their interest in entering into a long-term off-take agreement for the supply of sulphuric acid,” Vedanta Zinc International said in a statement. In Namibia, it plays a critical role in mineral processing, especially in uranium mining, where it is used in heap leaching to extract uranium oxide from ore. The country’s fertiliser producers also rely on sulphuric acid as a feedstock in the manufacture of phosphate fertilisers. At the same time, other industries use it in metal treatment, water purification and chemical production. Namibia currently imports most of its sulphuric acid requirements, and the restart of Skorpion’s plant is therefore likely to reduce dependence on imports and strengthen the resilience of local supply chains. It could also create opportunities for export to neighbouring countries, including South Africa and Botswana, where acid demand continues to rise. Vedanta Zinc International, a subsidiary of Vedanta Limited with a market capitalisation of around US$30 billion (about N$550 billion), manages a portfolio of zinc assets in southern Africa. These include producing mines in South Africa’s Northern Cape as well as the Skorpion operation in Namibia, which has remained dormant since open-pit reserves were depleted and technical challenges emerged in processing zinc-oxide ore. Although full-scale mining at Skorpion has not resumed, Vedanta has sought to maintain its presence in Namibia through strategic investments and infrastructure management. The decision to restart the acid plant is seen as part of a broader effort to keep the site active while the company evaluates long-term options for zinc mining and refining in the country. Industry observers say the recommissioning of the Skorpion acid plant sends a strong signal of Vedanta’s continued interest in Namibia’s mining and industrial landscape. It may also provide a platform for future partnerships, particularly as the country looks to expand its industrial base and add value to mineral resources before export. If successful, the project will not only revive a dormant piece of infrastructure but also reintroduce a steady domestic source of a chemical that underpins Namibia’s mining and agricultural industries. In the process, Vedanta aims to reinforce its credentials as both a responsible operator and a partner in Namibia’s economic development. May 30, 2020 - The unstable morphology of the open pit and the extensive losses from labour strikes are cited by the owner of the Skorpion Zinc mine and smelter, Vedanta Zinc International, as two of the major reasons why they have decided to place the mine on Care and Maintenance, starting with the process next month. Vedanta Zinc International acquired the mine and smelter in 2011 as part of the acquisition of Anglo American’s zinc portfolio. The mine is located in Namibia’s deep south, just a few kilometres north of the Orange River, the border with South Africa. Vedanta said at the time of the acquisition, the mine’s end of life was projected for 2014. Since Vedanta became the new owner, it has invested more than US$1.6 billion to extend the life of the pit and to explore for new deposits. US$25 million was spent on exploration alone. This investment helped to implement a mine-life extension project which started in April 2017, with the intention that end of life will be reached in May 2020. At this point, Vedanta planned to close the mine and put the smelter under Care and Maintenance. “However, significant events (pit stability) and inefficiencies (including labour disruptions) during this period have resulted in intermittent stoppages and/or delays which have in turn unfavourably extended the project timeline and significantly eroded project value,” Vedanta stated this week. A major failure in the structure of the open pit last year, coupled with smaller failures, resulted in an ore gap of more than 10 months, despite the failures being mined out safely. In the meantime, further technical studies have indicated that more failures can occur at depth. The last such failure happened earlier this year in January. “The safety of all employees is our first value. As a result, the decision has been taken to cease all mining operations while studies continue to look at feasible ways to make the pit safe for mining options which would allow for the extraction of the remainder of the accessible ore,” said Vedanta. The decision to cease mining affects about 1500 employees whose futures will be determined by the negotiations between Vedanta and the Mineworkers Union of Namibia. March 31, 2020 - VZI decided to temporarily close the refinery, based on a substantial reduction of ore from its Pit 112, resulting in the operational and financial decision to close the refinery for a few months. According to the mine’s spokesperson Nora Ndopu, the failure was safely and successfully mined out. “However, more (smaller) failures have since occurred, with the latest one in January 2020 sterilising a significant portion of the open pit. This has resulted in an ore gap in excess of 10 months. Further technical studies have indicated the existence of similar such failure structures at depth. The safety of all employees is our first value – as a result, the decision has been taken to cease all mining operations, while studies continue to look at feasible ways to make the pit safe for mining options, which would allow for the extraction of the remainder of the accessible ore,” Ndopu explained in a statement. Ndopu added that VZI remains focussed on prioritising growth projects to create a sustainable life for SZ and to shorten the care and maintenance gap. She continued that accelerated focus will now be on the Refinery Conversion Project to enable co-treatment of both sulphide and oxide ore, which was originally announced in 2014 with the Gamsberg Phase 1 Project but was deferred due to the Pit 112 life extension. A feasibility study that was completed in 2015 is now being refreshed. VZI acquired SZ as part of the acquisition of Anglo American’s zinc business in 2011. The envisaged life of mine of SZ was then 2014. Ndopu pointed out that SZ has invested significantly since Vedanta took over to extend the life of the pit and explore for mines in the nearby areas, with over US$1.6 billion invested, including US$25 million on exploration alone. Said Ndopu: “When VZI embarked on the SZ Pit 112 mine-life extension project in April 2017, the successful completion of the project and thus mine closure and refinery care and maintenance were envisaged for May 2020. However, significant events (pit stability) and inefficiencies (including labour disruptions) during this period have resulted in intermittent stoppages and/or delays which have in turn unfavourably extended the project timeline and significantly eroded project value. December 3, 2010 - Sterlite Industries (India) Limited (“Sterlite”) today announces the completion of the acquisition of the Skorpion Zinc Mine (“Skorpion”) in Namibia from Anglo American plc (“Anglo American”) for a cash consideration of approximately $707 million. On 10 May 2010, Vedanta announced the acquisition of Anglo American’s Zinc Assets (“Anglo Zinc”) - for a total cash consideration of $1,338 million, on an attributable, debt and cash free basis. Anglo Zinc comprises the 100 per cent owned Skorpion mine in Namibia, the 100 per cent owned Lisheen mine in Ireland and the 74 per cent owned Black Mountain Mines, which includes the Black Mountain mine and Gamsberg project in South Africa. Skorpion has been acquired by a subsidiary of Sterlite Infra Limited, itself a wholly owned subsidiary of Sterlite. It was intended that the acquisition of Anglo Zinc would be undertaken by Hindustan Zinc Limited (“HZL”), a subsidiary of Sterlite, subject to approval from the Indian Government as shareholder, which was not received within the contractual completion timeline for Skorpion. The acquisitions of the Lisheen mine and Black Mountain Mines are expected to be completed on schedule Anglo Zinc is an excellent operational and strategic fit with our existing business and will create significant long term value for shareholders. This acquisition will consolidate our position as the world’s largest integrated zinc - lead producer with significant reserves and resources of 478 million tonnes. Commenting on the transaction, Anil Agarwal, Chairman said: "We are delighted to have completed the first phase of the acquisition of Anglo Zinc assets. Skorpion Zinc Mine is a high quality zinc asset and will complement our existing portfolio. We look forward to working with Skorpion’s team and remain committed to maintaining the highest standards of sustainability and exploring growth opportunities.”

MTPD - Metric Tonne per Day STPD - Short Ton per Day
MTPA - Metric Tonne per Annum STPA - Short Ton per Annum
SA - Single Absorption
DA - Double Absorption

* Coordinates can be used to locate plant on Google Earth