Eritrea – ASX-listed South Boulder Mines has completed a technical review of staged deliverables of the pre-feasibility study (PFS) process design, process design criteria, metallurgical testwork, plant configuration, and process equipment list for its Colluli potash project – the world’s first, modern, open pit potash mine, located in the Danakil Depression region of Eritrea, in east Africa.

The process review, requested by South Boulder and Australia-based EPCM consultancy Lycopodium, was completed by the Colluli process technical review committee was established in January 2015. Following initial independent assessments, the committee met in Denver, Colorado in February to review the PFS design and testwork.

The committee also reviewed the definitive feasibility study (DFS) optimisation metallurgical testwork and pilot test programme which are currently under way, to ensure adequacy of the test program in all critical elements of the process design.

The committee comprises experts Don Larmour from Global Potash Solutions, David Butts from DSB International, John McEwan from McEwan Chemical Engineering Consulting and Tom Broderick from Hazen Research, Inc.

The key findings of the review concluded that the process design for the production of SOP from the Colluli resource is functional, feasible, uses well proven processes and technologies, and is underpinned by testwork that confirms the validity of the process flow diagrams.

The review has also identified a number of potential enhancements in the overall process design that will be further examined as part of the DFS, while recommendations have also been made for specific tests to be completed as part of the DFS pilot test programme.

South Boulder’s Managing Director, Paul Donaldson said: The recently released PFS for Colluli demonstrates that the project will be one of the lowest cost potassium sulphate producers in the world. Colluli is underpinned by a large resource that has the potential to grow a multi-agrichemical business of global significance.

South Boulder is pleased that the process design and testwork to date has been endorsed by a highly capable and experienced team of industry experts. No material issues have been identified, and a number of opportunities for improvement have been put forward to integrate with the DFS.

The project will focus on a modular development path, with the first two modules each producing an expected 425 000 t of potassium sulphate a year.

Colluli has a unique composition of potassium bearing salts in solid form, suitable for the production of both potassium sulphate and potash of magnesia. These are premium potassium fertilisers used in the agriculture industry with limited primary production globally, due to resource scarcity.

Top Project Stories in Eritrea:

South Boulder to complete east African Colluli potash PFS and DFS this year