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Nowadays, the maintenance of wellbore stability is a very important activity in the drilling industry. Wellbore stability can be improved by designing proper drilling fluid. Due to the characteristics of shale formations in relation to its ionic composition, clay content and very low Nano-Darcy permeability with very small nanometer-sized pore throats that are not effectively sealed by the solids in conventional drilling fluids, water invasion to these types of formations results in many problems. Choosing appropriate nanomaterials with suitable particle size and concentrations for plugging the nano-sized pores in the shale formations is key in preventing water flow into the shale region. Water based mud performance and rheological properties improve due to the importance and unique properties of Multi-Wall Carbon Nanotube (MWCNT) such as thermal stability more than 600 °C, high chemical stability, huge surface area, high aspect ratio, light weight, larger flexibility, high mechanical strength and superior electrical properties.

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Tookallo, Koorosh
Koorosh Tookallo, Master of Science: Studied Petroleum Engineering at Azad University. Project Manager at Parsayan Pooyesh Aseman.Co.Ltd.PVT, Tehran. Iran.

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