Canadian-based international mining company, Dundee Precious Metals says its Tsumeb zinc smelter has missed its 2022 production guidance.
The company announced preliminary production results from both of its mines in Bulgaria and the Tsumeb smelter for the three and twelve months ended December 31, 2022.
In the fourth quarter, the Tsumeb smelter processed 41 800 tonnes of complex concentrate. Results were impacted by a 17-day shutdown to repair a water leak in the offgas system and instability in the power grid as a result of abnormally heavy rainfall in December, Dundee explained.
Dundee Precious Metals is reviewing its full-year guidance for its Namibia based, Tsumeb smelter after it produced 21 100 tonnes of concentrate in the second quarter, taking the year-to-date total volume of concentrate produced to 68 300 tonnes; while full-year guidance for the smelter ranges between 210 000 t and 240 000 tonnes.
The low production was attributed to the unplanned downtime as a result of water leaks that were resolved during the planned Ausmelt maintenance shutdown completed during the second quarter.
“Nonetheless, because of the smelter’s performance in the first six months of the year, Dundee is reviewing its full-year guidance for Tsumeb, as complex concentrate smelted is expected to be lower than the current range with cash cost a tonne smelted expected to increase as a result of the lower production.”
“This 45-day shutdown included additional maintenance to the off-gas and baghouse systems, which is expected to improve operational performance moving forward.”
President and CEO David Rae said with the completion of the planned maintenance at the Tsumeb smelter, Dundee expects improved smelter performance over the balance of the year.
A few years ago, Dundee Precious Metals Tsumeb proposed to expand their current smelter operations in Tsumeb in order to increase the copper concentrate throughput capacity from 240,000 tons per annum to 370 000.
Dundee said the expansion would be contained within the existing facility footprint and would include the following components, to upgrade the existing Ausmelt feed and furnace, to install a rotary holding furnace, the implementation of slow cooling of the furnace and converter slag, the upgrading of the slag mill to improve copper recovery and handle the increased tonnage from slow cooled slags, the option to install an additional Peirce-Smith converter and to relate infrastructure improvements.
The Tsumeb specialty smelter is one of only a few in the world which is able to treat arsenic and lead bearing copper concentrates and is therefore able to conclude long term favourable contracts to treat such concentrates. Both blister copper and arsenic trioxide (As2O3) are produced from the concentrates. The blister copper is delivered to refineries for final processing and the As2O3 is sold to third party customers.
Tsumeb Smelter has become a major custom smelter with brown-fields expansion potential. It produces blister copper (98.5% Cu) and has the ability to treat complex copper concentrates.
The facility consists of two primary smelting furnaces, the old reverberatory furnace as well as the refurbished Ausmelt furnace and employs close to 600 people, including contractors.
As part of its corporate social responsibilities, the company has spent over N$23.3 million in the Tsumeb community on environment, arts, social welfare, SME’s and education initiatives.
The company contributed approximately N$6 million to public-private partnership with the National Housing Enterprise to build houses for Dundee employees.
The smelter employs approximately 1684 employees including contractors.