Specialty smelter looks to the future

Tsumeb's specialist copper smelter processed 52 900 tonnes of complex concentrate between April and the end of June. The plant’s best ever throughput was recorded in 2018 when 232 000 tons were processed.

These days the ore comes from South America, Zambia and to a lesser extent from Opuwo, according to Herman Fuls, director of technical services at the plant.

In recent history the plant, first built in the early 1960’s, operated on a integrated basis with owner’s Dundee Precious Metals’s Chelopech copper mine, but last year more than 75% of complex ore smelted was from other third parties. The plant produces blister containing copper, gold and silver, which is sold to refiners in Europe and Asia, as well as sulphuric acid, predominatly sold to Rossing Uranium Mine.

Meanwhile, the Namibian Competition Commission (NaCC) is investigating the sale of the plant by Dundee Precious Metals to China's Sinomine Resource Group. According to Johannes Ashipala, the head of the investigation delegation, the investigation continues after a recent visit to the plant, with input to be submitted before a scheduled meeting of the NaCC board in August. He elaborates that the commission not only looks at competitiveness issues, but also at possible issues of public interest.

The director of sustainability and business transformation at the smelter, Barcelona Tsauses, insists that major investments, innovation and hard work have transformed the plant into an example of environmental stewardship, which protects the public interest.

Tsauses was the driving force behind the Canadian listed company's Project 2012, which was launched just after Dundee bought the smelter in 2010.

The project kicked off the investment of US$515 million (N$9.26 billion) with the construction of a sulfuric acid plant, to transform the smelter plant in terms of safety and health.

Dundee's process engineer, Klemencia Kambonde, says the second oxygen plant, the Ausmelt furnace with its improved gas collection system, the sealed arsenic storage facilities, the improvements at the arsenic plant, the new warehouse for arsenic packaging, the new gas converters and air ducts built since then work well together .

Dundee was engaged in Project P300 (N$57 million) from 2020 to 2023 to further optimize the smelting process and reduce costs, before China also started smelting complex copper ore and ore from Dundee's mines in Bulgaria is now being taken there.

The Canadian owner’s focus on gold and precious metals led to the US$49 million sale decision, Tsauses elaborates.

The smelter's environmental clearance was renewed in January 2023 and extended until 2026.

Water use has reduced by 40% since 2012 and contaminated water with the arsenic is captured and safely stored, while 98% of the sulfur dioxide is now converted into sulfuric acid, according to Dundee.

Inekela Iiyambo, the superintendent for the environmental at the smelter, says a lot of work has been done to improve water management and the conservation quality of capital projects in general. Tailings management and active decarbonisation efforts, including a power purchase agreement which will see 30% of electricity needs covered by an independent solar power purchase agreement, have all helped to achieve considerable improvement in fauna and bird bio-diversity in the immediate area. “The air is cleaner,” he adds.

Medical surveillance at the plant is strictly enforced and protective clothing is enforced, with significantly fewer injuries and measured air and water purity results for arsenic at 0.04mg/m³, well below the legal limit (0.1mg/m³), according to Dundee.

Employing more than 1,300 employees, the smelter's chief legal representative, Zeka Alberto, recently assured that management and culture will be maintained and that it will be business as usual, even under new owners. "Our people are our power," says Tsauses.