ASX- and Aim-listed European Metals' 49%-owned subsidiary Geomet has approved the adoption of tunnel kiln technology for the Cinovec lithium project, in Czech Republic.

Geomet originally planned to use two gas-fired rotary kilns but has suggested to its board a single electric tunnel kiln to reduce the project's dependence on gas and and enable the project to run solely on green power supplied by State-owned energy company CEZ, which is also Geomet's 51% shareholder.

European Metals chairperson Keith Coughlan says the use of a tunnel kiln is an important change from the definitive feasibility study of the Cinovec project, resulting in a significant reduction in both capital expenditure and operational expenditure relating to the reduction in the roasting temperature of the Zinnwaldite concentrate and the option to use electricity instead of gas to fire the kilns.

"The use of green electricity to fire the kiln could also significantly reduce the carbon footprint of the project, enabling Cinovec to be a leading low carbon producer of lithium carbonate," Coughlan adds.

The Cinovec project is poised to produce 37 500 t/y of lithium carbonate, with the next stage of the project's development being detailed design and execution-level engineering.

Coughlan warns that while the Geomet board has approved the technology switch, a final decision has not yet been made over the choice between gas-firing and electrical heating. The approval is subject to satisfactory agreement of testwork contracts and a preliminary market consultation, as required under the Czech Public Procurement Act.

Notably, the use of a tunnel kiln is not expected to impact the project's timeline. In fact, the design and construction of a tunnel kiln is generally simpler and modularised with short sections manufactured off-site. Tunnel kilns also offer minimal heat losses and cost less to install than rotary kilns. The tunnel kiln does not require amendments to the environmental impact assessment for Cinovec.

Geomet plans to undertake more testwork on site to increase lithium roast/leach extraction by several percent and reduce reagent use. The Cinovec Phase 3 testwork will include the construction of a "shuttle kiln" with two kiln cars that will be used to test 1.5 t of briquettes for each test.