Effect of Activated Charcoal on the Rheological and Filtration Properties of Water Based Drilling Fluids

This research article investigates the effect of activated charcoal on the rheological and filtration properties of water based drilling fluids with the objective of the development of non-damaging drilling fluids to drill the sensitive formations. Initially, base drilling fluid combinations were prepared using xanthan gum, polyanionic cellulose, pregelatinized starch and potassium chloride and rheological and filtration properties were measured using API standard methods. These drilling fluids show better rheological properties but poor filtration loss characteristics. To control the filtration loss characteristics, activated charcoal, a new bridging material was added with these drilling fluids and the performance of this additive was compared with calcium carbonate, a conventional bridging agent. The experimental investigation furnishes that activated charcoal has better control on the filtration loss characteristics without affecting the rheological properties of drilling fluids and the drilling fluids developed using this bridging material may have good potential for the drilling of oil and gas wells.