Minemakers Limited: Wonarah Phosphate Project Positive Dry Kiln Testwork Progress

Minemakers Limited: Wonarah Phosphate Project Positive Dry Kiln Testwork Progress

Minemakers Limited is very encouraged by the testwork results to date with respect to phosphorus recovery using the patented dry kiln process, rather than the conventional sulphuric acid wet technique.

– Testwork by JDCPhosphate Inc in Florida has been undertaken on expected “run of mine” phosphatic product from Wonarah and averaging about 20%


– About 15% of the known extent of phosphate mineralization has been sufficiently drilled thus far to enable resource estimation. At a 10% cut-off, there is currently an estimated 289Mt at 18.5% P2O5 in the indicated resource category and 331Mt at 17% P2O5 in the inferred resource category for a total of 620Mt at an average 18% P2O5. These

resource estimates are both JORC and NI43-101 compliant.

– Satisfactory pelletisation of product for dry kiln feed has been achieved, at batch test scale, using commercial binders and balling


– Firing of the balls at pilot scale by JDCPhosphate has resulted in 97%
phosphorus recovery.

– The iron, alumina, magnesium and calcium all stayed in the pellet after
heating in the kiln.

– The high phosphorus recovery is due to the low iron content (about 0.6%)
in Wonarah phosphates.

Follow up batch-scale testwork is scheduled to begin in the last week of March at the Metso Laboratories in Danville, Pennsylvania. Minemakers’ General Manager Projects Development, Neville Bergin, will be in attendance so that Minemakers gains an increased appreciation of the optimal mine feed for kiln processing and the related engineering and infrastructure requirements.


On 2 September 2010 Minemakers announced that it had invested US$1 million in JDCPhosphate Inc for which it has gained initial sole Australian rights to use that company’s patented “Improved Hard Process” dry kiln technology for the production of phosphoric acid for a commercially significant time. That technology has promise to:

– Deliver phosphoric acid by a dry kiln technique rather than a
conventional one using sulphuric acid (the wet technique).

– Deliver significantly cheaper capital and operating costs than the wet

– Be much more environmentally friendly.

– Be particularly suitable for Wonarah’s phosphate rock composition.

– Produce premium grade superphosphoric acid which is currently priced at
US$920/t (100% phosphoric acid basis).

– Significantly reduce Wonarah’s operating costs because of the ability to
freight lower tonnages on a per weight of phosphate output basis.

Minemakers’ Managing Director, Andrew Drummond, stated: “Minemakers is very pleased with the dry kiln testwork results to date. While shareholders are aware that we are vigorously pursuing the potential to attract significant Asian investment capital for a full scale development of Wonarah, which would involve downstream processing options, the dry kiln phosphoric acid gives an exciting alternative or parallel development option. On the data at hand, it promises to offer a lower capital and operating cost with better operating margin. We await the results of the batch scale testwork with great interest.”

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