Characterisation and Processing of Baryte Ores for Oil Drilling Applications

Afolayan, David (2021-12-12)


This study characterizes barite ores and uses environment-friendly and indigenous processes to develop technologies, methods and mineral processing tools for barite recovery from gangue minerals. The study is in four parts. The first project characterizes some Nigerian barite rocks and on-the-site processed barite as a weighting agent for oil drilling mud applications. In project II, the Nigerian barite rocks/ores were further processed by jigging. In the third and fourth projects, the impact of artisanal and small-scale barite mining and processing on human health and the environment was examined, assessed, and characterized to pursue sustainable development goals (SDGs) 3, 12, 13, and 14. The physicochemical and rheological properties of the on-the-site (locally) processed barite ores revealed that Nigeria barite could replace theindustrially accepted barite used as a weighting agent for oil drilling mud. Barite ores were randomly selected, comminuted, screened, characterized, and beneficiated using a laboratorybuilt mineral jig. The effect of mineral liberation on separation efficiency, recovery, and yield was examined. The specific gravity of the barite ores was increased from 3.97±0.0105 to 4.17±0.20 and from 4.00±0.0458 to 4.20±0.2 without the use of chemicals. Likewise, higher barite recovery and yield were observed. Yet, the separation efficiency of the jigging process was low due to the presence of middling (a complex particle with gangue minerals associated with the value minerals). Project III also examined existing but weak institutional frameworks and policies for artisanal and small-scale barite mining. The results of safe mining assessment by ICP-MS and AAS analyses confirmed lead, barium, zinc, copper, and iron in the tailing effluents and barite pond. The survey showed that 54% of artisanal miners had health challenges traceable to illicit drugs and were ignorant about using safety kits during barite mining. The physicochemical studies for risk identification, assessment, and characterization revealed the extent of heavy metal contamination in mine water and tailing effluents for project IV. The toxicity and the extent to which the miners and entire mining community are exposed to the heavy metals contamination were evaluated, and the potential risks to human health due to barite mining and processing, estimated. The regular daily intake assessment and health quotient analysis revealed the accumulation of Pb and Ba is possible and can initiate chronic disease in humans over a long time. Some preventive measures to avert the carcinogenic risks of Ba and Pb were recommended to ensure a responsible and sustainable extraction of barite mineral mining.