European Metals Holdings Limited (ASX & AIM: EMH) has unveiled significant developments in the processing flowsheet for the Cinovec vertically integrated battery metals project in Czech Republic.
The completion of flowsheet development work in both the FECAB and LCP is a significant milestone for the Cinovec Project,” Executive Chairman, Keith Coughlan, said.
“The simplification of the process, the improved economics, and the addition of two new significant potential end products are all very pleasing results. This simplification, in reducing the complexity and in reducing the steps required in the LCP process from 15 to 7, eliminates some potential process flowsheet risks.
“Testwork to confirm optimised FECAB and LCP flowsheets is now complete and production of significant quantities of battery grade lithium chemicals is expected to be available for distribution to long term European offtake partners early next year.
“The quality of the product is also excellent with almost battery grade material produced as our crude material. In addition, the reduction in both reagent use and energy consumption add to already excellent ESG credentials.
“Now that the simplified flow sheet has been released to the market, the company looks forward to being able to provide more frequent updates regarding progress towards completion of the Definitive Feasibility Study (DFS) based on the new flowsheet as well as progress on the offtake discussions in which the Company has been engaged.”
Simplification of the LCP flowsheet
The simplified LCP flowsheet has been tested in six (6) Locked-Cycle Tests (“LCTs”) at ALS Global in Perth. This simplified new flowsheet has demonstrated overall lithium recoveries of 88-93% in the LCTs programme.
In the programme of six LCTs for the earlier flowsheet, recoveries of 85-87% lithium were demonstrated. The new flowsheet therefore represents an outright lithium recovery improvement of 3-6%.
After roasting and leaching, the pregnant leach solution (PLS) is passed through two cleaning steps to remove transition metal and calcium impurities, resulting in a “polished” PLS of lithium sulphate together with sulphates of other similar metals, principally sodium and potassium.
The earlier flowsheet continued to remove unwanted elements before precipitation of a “crude” lithium carbonate. The last step in the earlier flowsheet was to purify the crude lithium carbonate with a bicarbonation and crystallisation step.
The simplified flowsheet precipitates lithium phosphate directly from the polished PLS and then goes on to clean the lithium phosphate to enable precipitation of a much cleaner crude lithium carbonate. The final purification step of bicarbonation and re-precipitation is the same as in the earlier flowsheet but the end-product is of even higher quality due to the input crude lithium carbonate being much cleaner.
The simplification of the central section of the LCP flowsheet reduces the number of basic chemical engineering unit processes (after the initial roast/water leach) from 15 to 7. The revised process also results in the elimination of all energy-intensive cooling processes.
European Metals has been advised by its principal hydrometallurgical adviser, Lithium Consultants Australasia (LCA), that the changes to the LCP noted above are expected to reduce both Capex and Opex in the LCP by 10-20%. The basis for this range of estimates is an expert assessment and adjustment by LCA of the equivalent Capex and Opex prepared by Hatch Associates Pty Ltd for the PFS for the production of lithium hydroxide published by EMH in 2019.
The Capex reduction is based upon the fact that the simplified flowsheet requires the use of only two crystallisers vs the four crystallisers and one evaporator in the original flowsheet. The similar reduction on Opex in achieved through reduced power use resulting from not having to operate the additional equipment. In the 2022 PFS Update, the LCP represented 49.8% of the Capex of the Cinovec Project and Opex/tonne for the full process to produce lithium hydroxide monohydrate (ignoring by-product credits) was US$6,727.