Criticality Testing of Drilling-Fluid Solids-Control Equipment

Summary Correct selection and use of solids-control equipment are essential in not only maintaining drilling fluid at its desired properties but also in avoiding the generation of unnecessary waste streams during drilling. Since the early 1930s, the shale shaker has been the dominant device for primary-solids removal. Additional equipment (e.g., desilters, desanders, and centrifuges) was often used in the past to maintain proper solids control, but experience in recent years has demonstrated that, although dependent on correct operational procedures, several types of shale shakers have sufficient performance to act as the sole solids-control devices without the use of desanders and desilters. Despite often being the only measure for solids removal, the selection of shale shakers, the screening, and the establishment of operational procedures are often based on biased information (Dahl et al. 2006). In addition, it has been recognized that methods and criteria for the verification of shale shakers have not been sufficiently qualified and standardized. To address this, a multidisciplinary verification test of various solids-control concepts has been conducted. The objective of the test has been to verify equipment performance in a standardized, onshore test facility related to Oil-mist and vapor emissionVentilation (to obtain a satisfactory working environment)Flow-handling capacity with various drilling fluidsLeakage rate (i.e., the volume of fluid bypassing the filtration screen)Lost-circulation-material featureNoise and vibration levelMaintenance and equipment robustnessFeature for running lost-circulation-material reclamation The tests were all planned and run in close cooperation with the equipment suppliers to ensure test-objective alignment. Several findings were made throughout the test period that provided vital information for design improvements and increased the industry's competence with respect to solids control.