An Insight into the Sources of the Bentonite used in the Local Drilling Industry

Abstract

Bentonite is a type of clay mineral that is used in a variety of applications such as drilling, sand casting, pelletizing iron ores, in insecticides, pet-litter, pharmaceuticals and cosmetics.  In this paper, the findings from a preliminary study on the use of Bentonite in the local drilling industry are discussed. Special focus is paid on the sources of the bentonite that is used in the drilling of bore holes, geothermal wells, and coal exploration cores. Findings from the study showed that both imported and local bentonites are used locally in drilling. Comparatively, imported bentonite accounted for upto 67.49% of the drilling industry market share as opposed to the local bentonite which takes the remaining pastry 32.51%. This drains the country’s foreign exchange and leaves the local bentonites unexploited fully. The consumption levels also appeared to be on an upward trend for both. The quantities of imported and local bentonite  for drilling use increased by 55.56% and 56.29% respectively for the period between 2006 and 2010 reflecting increased demand for this clay. From the study, it was also found that none of the drilling companies involved in the study carried out routine tests on the bentonite before or during drilling, basically due to lack of standard testing equipment. In general, formal methods for the characterization of bentonitic clays are lacking. The different venues for the standardization of the clays for drilling work are highlighted in this paper.