Suitability of Nigerian Barites for Drilling Mud Production and Sustainability of Artisanal and Small Scale Mining (Asm) of Barites In Nigeria
The aim of this dissertation is to contribute to efforts towards increasing the use of Nigerian barites in drilling mud production and other industrial applications. In order to achieve the above objectives, three projects were conceived and implemented. The aim of the first project was to characterize barite samples from selected different locations in Nigeria and determine their suitability for different industrial applications. The properties determined include chemical composition, functional groups and specific gravity. Samples were obtained from ten locations in Nasarawa and Taraba states as well as a standard Working Sample (WS) obtained from a drilling site. The samples were characterized using Scanning Electron Microscope & Energy Dispersive X-Ray (SEM-EDX), Fourier Infrared Analysis (FTIR) and X-Ray diffraction (XRD). Specific Gravity (SG) was determined using pycnometer method. Results of SEM-EDX analysis show that the WS has a B-S-O empirical composition of 66.5%while the ten samples investigated had compositions of between 59.36% and 98.86%. The FTIR analysis shows that the functional groups of S-O, SO4-2, B-S-O, OH of the ten samples match that of the WS. Results of XRD show that the ten samples have the same elemental composition as the WS and all meet American Petroleum Institute (API) standard for industrial barite. Similar matching results are shown from EDXRF spectra intensity, position and composition analysis of the ten samples compared to the WS. Specific Gravity (SG) results show that six out of the ten samples have SG above 4.2 which is the recommended minimum for API standard. The other four samples will require beneficiation to meet the standard for drilling fluid formulation. Using all the parameters of the assessment together, results show that while some (6) of the samples can be used for drilling fluid formulation, some (4) require beneficiation but all ten samples can be used for other industrial applications. The second study is focused on improving the productivity and sustainability of Artisanal and Small- scale Mining (ASM) of barites This study: reviewed the existing policies and government interventions on ASM of Nigerian barite; evaluated the operations of ASM through a survey of mines in Nasarawa state, Nigeria; identified factors that affect sustainability of the sector and proffered solutions to foster sustainability of ASM of barite in the region. The study adopted the 4Is optimization technique (Information gathering, Interpretation, Implication Implementation) through personal interactions with the stakeholders at the barite mining sites, regarding policies and interventions specific to ASM of barite. Challenges identified include: weak implementation and enforcement of mining laws; inadequate support from government and development partners; poor access to mining equipment and technology; poor infrastructure (access road, water, electricity); poor pricing of products (marketing challenges); poor remuneration of mine workers; poor mining skills; inadequate formal education; limited awareness on environmental health and safety hazards; fragility and conflict; insufficient information and data on mines and miners; security, fragility, and conflicts; lack of access to finance; lack of formalization of operations and poor legal framework for operations. The strategies suggested for fostering the sustainability of ASM of barites include: enhanced policy and legislation formulation and implementation, strengthening of institutions, formalization of ASM operations, training of miners, awareness campaign, improvement in environmental and safety of operations, empowerment and support by government and development partners for individual miners and processors and organized groups within the sector. The third project examined the role of male and female miners and the impact of Artisanal and Small-Scale Mining (ASM) of barites in Nigeria on environment and safety through a field survey using a structured questionnaire and Focused Group Discussion. Results show that barite miners consist of 52% male and 48% female. Men (100%) are mostly involved in blasting, digging and cracking while women (100%) are involved in cleaning, washing and transfer of excavated barite to designated locations for stacking. The gender challenges identified include: unsafe work environment and poor remuneration for women; inadequate enforcement of mining laws and regulation, poor access to finance, disparity in access to safety gears, degraded environment and devastation of agricultural land. Recommendations include: modification and implementation of existing ASM policy to emphasize gender mainstreaming, support programs for gender parity for the sector, formalization of activities of ASM and creation and support for women cooperative miners.