Sparton Resources reported that it has received initial uranium extraction test results on coal ash from the Yunnan Xiaolongtang Power Station in southwestern China.

The test work is being done under the direction of Lyntek Incorporated, and represents early stage testing of fly ash and bottom ash samples from Xiaolongtang that contain approximately 0.46 pounds of U308 per tonne of ash (160-180 parts per million uranium).

The first phase of test work involves several acid and alkaline leaching tests on both the fly ash and bottom ash samples which have different physical characteristics. Chemical reagent concentrations and test conditions are progressively adjusted in subsequent tests to work towards increased recoveries, and at this stage only very simple techniques have been used. Because the Xiaolongtang Power Station uses lime to reduce sulphur stack emissions the excess lime content in the ash is also a factor in determining the testing program. Current results indicate that acid leaching is the most effective method of uranium removal. Because fly ash represents over 90% of the ash production, and future work will prioritize tests on this material.

The first simple test results on fly ash samples using weak sulphuric acid solutions averaged recoveries of about 45% of the contained uranium into the leach solution and residues. Further testing using different reagent concentrations has increased this now to 73% soluble uranium in the leach solution and residues. These results are considered very positive and compare favourably with realized and projected uranium recoveries from public documentation of currently operating and proposed new ISL (In Situ Leach) uranium mining operations, which average about 70% uranium recoveries.

The next phase will involve bench scale heap leach tests on agglomerated fly ash to lower the acid consumption and advanced leaching tests using oxidants and other methods to improve the overall uranium solubility in the test solutions. Once this has been optimized final recovery tests for U308 will be established in a preliminary flow sheet and larger scale tests will be commissioned leading towards a scoping or pre-feasibility study level of technical evaluation. This work will define the parameters for the possible commercialization of the Xiaolongtang program. As indicated in previous news releases the Xiaolongtang station is producing over 600,000 tonnes of fly ash per year containing over 275,000 pounds of U3O8.

As well, Sparton's China based team continues to obtain new samples of high uranium ash from other Chinese power stations and these are currently being analysed and will be sent for extraction tests in the coming weeks.

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