Tianping Huang

Nanoparticle Associated Surfactant Micellar Fluids

Surfactant micellar fluids, or viscoelastic surfactant fluids, have been used in the oil industry as completion and stimulation fluids. High fluid leak‐off and low thermal stability at elevated temperatures have, however, limited their application for hydraulic fracturing and frac‐packing applications. Improved thermal stability and rheological design of such viscoelastic surfactants is critical for non‐formation damaging, high temperature well treatments. This paper will introduce the interaction of nanoparticles with micelles, which at low concentrations induce micelle‐micelle associations and significantly improve the performance of viscoelastic surfactant fluids. The unique association of viscoelastic surfactant micelles and nanoparticles has demonstrated improved viscosity, the formation of a “pseudo‐filtercake”, and enhanced thermal stability. Laboratory tests show the development of a pseudo‐filtercake which significantly reduces the rate of fluid loss and demonstrates wall‐building rather than vis...

Improving Fracturing Fluid Performance and Controlling Formation Fines Migration with the Same Agent: Is it Achievable?

Traditionally, hydraulic fracturing (frac-packing) and controlling formation fines migration treatments are separate operations that incur high costs for operators, especially for offshore asset developments. Hydraulic fracturing or frac-packing treatment can reduce fines generated in the near-wellbore region, but not the fines migrating from deep hydrocarbon-producing formations. Separate treatment for fines migration control is usually required for maintaining wellbore productivity. Recent studies have found that some inorganic nanoparticles can significantly improve the performance of surfactant micellar fluids in hydraulic fracturing and frac-packing applications, including fluid thermal stability and fluid loss control properties. A theoretical model illustrates that the nanoparticles are first associated with the energetically unfavorable endcaps of surfactant micelles and then become the junctions of the wormlike micelles. Hydrophobic components as internal breakers are placed within wormlike surfactant micelles during surface mixing. After fluid pumping is completed, the internal breakers act to collapse the wormlike surfactant micelle structures. This causes the viscous frac-fluid significantly lose its viscosity and the nanoparticles are released. The released nanoparticles precipitate and attach to nearby proppants to act as formation fine fixators to capture fines when they flow through this region. Our lab tests detail this dual functional performance improvement of surfactant micellar fluid and the controlled migration of formation fines.