Question

A) What are the three key things that need to be characterised for a uranium mineral or uranium bearing ore before it is processed? B) Why is characterisation of an ore important? The three most commonly used methods to characterise a uranium bearing ore are XRF, XRD and electron probe microanalysis. C) Discuss the information that can be obtained using the aforementioned methods (and any potential shortfalls of these methods).

Answer 1

(A) Uranium is found in rock. The uranium ore is extracted through mechanical means such as blasting, drilling, pneumatic drilling, picks and shovels, and then transported to the surface. After mining, the ore is ground to a fine powder in a uranium mill.

(B) Ore characterization. In ore properties govern the ultimate performance that is achievable in all mining operations.The best possible characterization of the ore body will enhance the ability to extract better outcomes from a mine to mill application.
The greater the data, the better characterization of the ore body properties.Thus characterization is important in developing extraction and processing strategies which enhance the productivity gains possible from a mine to mill application.

The measured micro strain in the supersaturated a-uranium phase was used as a quantitative indicator for determination of the solubility limit of Ta and W in 7-uranium. X-ray diffraction (XRD) is a valuable technique that can yield considerable information on structure and properties of crystalline materials.

(C) Uranium bearing ores are often a complex mixture of minerals and compounds, a number of which are not of economic importance and are commonly referred to as gangue materials. In order to improve the efficiency of the dissolution stage of the overall uranium extraction process, a greater understanding of the minerals and compounds present in the ore is required. A greater knowledge of the gangue materials present is important as they can influence various aspects of the dissolution process such as providing potential adsorption sites for aqueous uranium species and through influencing the equilibrium of reactions involving aqueous uranium species. In this study the mineralogy of a uranium ore was investigated using a range of X-ray diffraction (XRD) based methods including in situ high temperature XRD and XRD using a synchrotron beam line. The results obtained from standard XRD, high temperature XRD and synchrotron XRD were compared and a number of minerals were identified. The improved spatial resolution and intensity of the synchrotron data allowed for superior phase identification of a variety of minerals where standard X-ray techniques gave inconclusive results.