CRITICAL REVIEW OF THE LITERATURE ON CURING LOSSES AND LONG-TERM SHALE INHIBITION

Lost circulation is one of the prevalent issues in drilling operations. It holds a negative impact on the oil and gas industry as it is a major source of non-productive time (NPT). Moreover, the process of elimination/control is timely and costly. Lost circulation is the loss of drilling fluids to geological formations rather than circulating back to the surface through the annulus. Lost circulation can be categorized based on the volume of fluid being lost to seepage, moderate, severe, or complete loss, and it occurs in the following types of formations: unconsolidated/highly permeable, induced or naturally-fractured, and vugular formations. The consequences of lost circulation include, but are not limited to, well control incidents, damage of formation, abysmal zonal isolation, and stuck pipe. Therefore, as the vitality of the well affects the quality of both drilling and production, curing lost circulation is essential. As the topic of lost circulation holds global significance in the oil and gas industry, huge amount of money is allocated to the research and development of solutions to the issue. Many researchers publish papers addressing different and innovative solutions to the ongoing challenge. Long term shale inhibition challenge will be detailed in the case of total losses. This paper will also show some experimental setup to test long term inhibition in the case of total losses.