Extension of PFS following favourable results
By <
http://www.southbouldermines.com.au/files/1360075.pdf> South Boulder
Mines,
02.09.2014
SOUTH Boulder Mines (ASX: STB) ("South Boulder" or "Company") has extended
its prefeasibility study ("PFS") on the Colluli Resource in Eritrea, East
Africa, to enable consideration of the impact of the following recent
favourable developments:
* The Company has completed its preliminary design for the production
of potassium sulphate (sulphate of potash) from the Colluli Resource
* The process utilises all potassium bearing salts in the Colluli
Resource which minimises the mining strip ratio. Scoping studies completed
in February 2014 demonstrated mining cost reductions of over A$50 per tonne
of product relative to the staged development model by using all potassium
bearing salts in the resource
* The process utilises proven technology and is employed in the major
potassium sulphate production centres in Utah, Chile and China
* The process design currently produces standard and granular
potassium sulphate
* There is a substantial price premium in producing potassium sulphate
over potassium chloride, and is the best and most value accretive
development option for the resource
Metallurgical testwork has identified two potential internal configurations
of grinding and flotation. Given the implications on capital and operating
costs, in the interests of achieving the right foundation work, the PFS
delivery will be extended to February 2015. It is envisaged the DFS delivery
will not be impacted and is still on track for mid-2015.
The project team has been running PFS and DFS workstreams in parallel, and
is well placed to complete many of the other workstreams while the
processing plant configuration is refined.
Managing Director of South Boulder Mines, Paul Donaldson, said:
"While we had initially planned to release the results of the prefeasibility
study by the end of 2014, we feel the process we are looking to adopt and
the favourable implications on capital and operating costs are significant
and need to be investigated more thoroughly.
"We feel that it is fundamentally important to get the groundwork right and
therefore we have extended the release of the PFS results until February
2015."
Mr Donaldson said the process would provide the lowest energy input, highest
potassium yield for the production of potassium sulphate.
"The process design ticks all the boxes so far - it uses all salts in the
resource, it takes advantage of the resource composition to produce a
premium potassium sulphate product, it maximises recovery by taking
advantage of the ambient conditions for the evaporation recovery ponds and
it is proven technology used in existing operations.
"The key difference between Colluli and the key sulphate of potash producers
is that Colluli starts with the raw materials in salt form rather than brine
which must first be converted to salts. This gives a substantial advantage
in reducing the plant's energy footprint and completely eliminating the
evaporation step to produce the feed salts."
General Manager of ENAMCO, Berhane Habtemariam, said;
"While we were expecting to have the PFS completed by the end of the year,
the Colluli Mining Share Company Board is supportive of exploring the
possibility of improving the internal configuration of the processing plant
to ensure the appropriate consideration is given to opportunities to reduce
capital and operating costs."
THE PROCESS PLANT
The process plant removes sodium chloride from the upper and lower layer
salts using conventional flotation, and then combines the resulting products
(potassium chloride and schoenite) which react under ambient conditions to
form potassium sulphate. Recovery of potassium is improved by capturing the
process brines and evaporating them to precipitate potassium bearing salts
which are fed back to the processing plant.
Given the substantial price premium of potassium sulphate over potassium
chloride, and the simple processing that is required to combine the upper
and lower salts of Colluli, this is the best and most value accretive
development option for the resource......
Read it in PDF further:
Berhane Habtemariam
Received on Tue Sep 02 2014 - 17:10:58 EDT