Impact of sand content on filter cake and invert emulsion drilling fluid properties in extended reach horizontal wells

In this paper, we evaluated the effect of sand content on the properties of the drilling fluid and filter cake during drilling a long horizontal section in sandstone reservoirs. Sixteen drilling fluid samples were collected and the initial properties were measured such as density and rheological parameters. HPHT tests were performed at 500 psi (the back pressure was 200 psi) to build the filter cake. The obtained results showed that the presence of sand caused significant change in the properties of mud and filter cake. The thickness of the filter cake increased about 35% to 40% of its original thickness. The mud yield point and 10 min gel strength increased by 40% due to the increase in sand content in the mud. Based on the real field data, empirical correlations were developed to predict the sand content in the filter cake using the drilling fluid properties measurements during drilling.