New Water Based Drilling Mud System with Double Clay Inhibition Shows High Performance at Drilling-Sites in Germany

摘要

Whereas inverse emulsion muds have remained the systems of choice for deep water wells and other technically demanding applications,the industry has made a concerted effort over the years to develop a water-based mud that can overcome the economical and environmental limitations for oil-based drilling fluids.Aqueous systems,such as silicates,glycols,partly hydrolysed polyacrylamides(PHPA)and others,have all been promising.Yet,they have only been partly successful,because while some of these systems show a high inhibition quality,their applications have been limited by other factors.This article describes the development and application of a water based drilling fluid system,which approximates the performance characteristics of an oil based mud.The new mud system comprises among others two products which work synergistically and which have been particularly developed for this purpose.The mud is thereby equipped with double clay inhibition ability:the inhibition of reactive and the inhibition of dispersive clays.The authors will analyze the performance of this newly engineered mud at various locations in Germany.The system consistently showed an excellent integrity of the drill cuttings and minimal residue at the pipes when penetrating reactive clays and also low degrees of dilution combined with a high rate of penetration at various drilling locations.Furthermore the mud system could be reused over several applications.