Drilling fluid processing: preparation, maintenance and continuous conditioning

The following discussion is an overview of the operation of drilling fluids at the rig site, giving an insight to those less versed in the art of drilling oil and gas wells. Fluid processing at the rig site is currently a prime target for higher levels of mechanization and process control, leading towards automation. The drilling fluids' composition influences its properties and dynamic behaviour, and the various drilling fluid components and additives all have specific purposes related to the drilling process. The process of drilling fluid preparation and mixing on the drilling rig is described, and the means of maintaining suitable properties during the drilling process are discussed. Means and requirements are presented for enabling continuous conditioning of the drilling fluid to suit the variations in the wellbore and formation, pointing out current challenges in measurement, instrumentation, mechanization, and control that need to be solved. It is clear that a higher level of automation is required if we wish to achieve this goal.