The era of drilling fluid property analysis carried out manually by a mud engineer is rapidly disappearing. Novel measurement tools and techniques are now making it possible to carry out sophisticated drilling fluid analyses using largely automated equipment. This paper anticipates and highlights the important role that automated particle size analyzers will play in future drilling operations. A comprehensive experimental study was carried out using a new generation of particle size analyzers (PSA) to investigate their utility for automated drilling fluid analysis. The pieces of equipment that were evaluated were the Canty Microflow LPA (which uses imaging microscopy), the Mettler Toledo G400 ParticleTrack (which uses FBRM laser diffraction) and the Malvern Mastersizer and Zetasizer (which use Dynamic Light Scattering). These instruments were used in conjunction with in-house flow loops and shearing facilities to test (1) degradation of the particle size distribution (PSD) of lost circulation and wellbore strengthening materials under the influence of shear, (2) the behavior of the emulsion droplet size distribution (DSD) of invert emulsion mud systems (oil-based and synthetic-based muds). Verifying and maintaining the PSD of lost circulation/wellbore strengthening materials is of crucial importance to prevent severe mud loss events that still continue to plague the industry at a trouble cost of many billions of dollars per annum. Our PSA analyses show that the PSD's of such materials, particularly those of medium to coarser sizes, is far from stable and degrades over time, primarily due to the influence of shear. It will be shown that automated, in-line PSA equipment allows for the degradation to be monitored and managed in real-time to maintain optimum drilling performance. In addition, such equipment can be used to monitor and optimize the DSD of an invert system, which is an extremely important quantity that influences many mud performance characteristics such as rheology, emulsion stability, fluid loss behavior, osmotic membrane efficiency, etc. The work involves a comparative study of novel PSA's, ranking them by accuracy, ease of use, automation potential, real-time monitoring capability etc. It presents novel, non-intuitive data on the degradation of lost circulation/wellbore strengthening materials, thereby allowing ways to manage this degradation. It also presents, for the first time, some preliminary work on the behavior of invert mud droplet size and its impact on oil-/synthetic-based mud performance.
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