Stability Modeling of Water‐Based Surfactant Covered Micro‐bubble Fluids

Abstract

Currently, due to the decrease in easy access to crude oil reservoirs, oil and gas industries have focused on production from heavy oil and depleted reservoirs. In recent years, micro‐bubble fluids with surfactant and polymer layers around the bubbles are investigated as a part of drilling fluids and their positive effect on the formation damage is proven. Stability of the bubbles in the fluid is very important, and the optimum surfactant and polymer types should be chosen at optimum concentrations. In this work, an attempt is made to analyze the stability of bubbles of the drilling fluid, based on the diffusive mass transfer concept. Mass transfer and interfacial mass transfer coefficients become more important when surfactant concentration gradient exists in micro‐bubble layers. Interfacial mass transfer coefficients have an important effect on mass transfer phenomena in Aphron fluids system; so, the precise selection of these coefficients results in the conformity of modeling and experiments. We can say that reducing the mass transfer rate from bubble layers will result in stable bubbles in the fluid and, thus, the efficiency of the fluid during drilling will not decrease. It is shown that the interfacial mass transfer coefficient decreases with an increase in surfactant concentration.

Experimental Investigation of Water Based Colloidal Gas Aphron Fluid Stability

“…Arabloo et al [10] employed a charged coupled device camera and a light microscope to investigate the size distribution of CGAs of different aphronized drilling fluids. Alizadeh and Khamehchi [17][18][19][20][21][22][23][24] proposed a new and novel diffusion model for CGA fluids including the mass transfer, which is described as diffusional phenomena in the presence of convective motion. In this model the mass transfer resistance for all phases and interfaces of a bubble was taken into account.…”

Mathematical modeling of the Colloidal Gas Aphron transport through porous medium using the filtration theory

“…In this type of drilling operation, fluid pressure must be maintained at a higher level than the formation pressure, but the pressure difference must not be so high to avoid fluid invasion into the formation rock (Belkin et al, 2005). Although more experimental investigation is carried out on Aphron fluid filtration and its related parameters (Sebba, 1987) (Brookey, 1998) (Ivan et al, 2001) (Ramirez et al, 2002) (Bjorndalen and Kuru, 2008), a few modeling works were carried out in the literature (Belkin et al, 2005), recently Alizadeh and Khamehch have published some works on the Aphron modeling and flow through porous medium (Alizadeh and Khamehchi, 2015a) (Alizadeh and Khamehchi, 2015b) (Alizadeh and Khamehchi, 2016a) (Alizadeh and Khamehchi, 2016b) (Alizadeh and Khamehchi, 2016c) When a solid free fluid is created due to environmental issues, the use of Aphron drilling fluids is considered. Bridging in the front of the porous media in near wellbore zone, in fractured or depleted reservoirs, reduces the formation damage and fluid depth of invasion into the formation.…”

“…The mass transfer partial differential equation (Alizadeh and Khamehchi, 2016a) (Alizadeh and Khamehchi, 2015b) (Alizadeh and Khamehchi, 2016c) for each layer of the bubble is as equation 1:…”

Mechanistic Study of Micro-bubble Fluid Infiltration through the Fractured Medium

“…Recent publications modeled a single bubble in deviated gas wells’ temperature and pressure . The stability of water-based bubbles and flow in porous media were studied by ref . Later, they worked on a model for predicting size distribution and liquid drainage from micro-bubble fluids using population balance equations .…”

“… There are several studies about micro-bubble drilling fluid penetration in porous media and fractures. The other researchers presented various aspects of these phenomena in their studies such as bubble size distribution, drainage rate, temperature, and pressure effects on micro-bubble fluid infiltration and bubble behavior modeling by mass-transfer concepts. − In addition, micro-bubbles size and rheological and filtration characteristics of colloidal gas aphron drilling fluids for a high-temperature well was investigated by ref . Le et al employed a new class of design of experiment (DOE) with definitive screening design to study the effect of five quantitative parameter of salinity, sodium dodecyl sulfate surfactant concentration, xanthan gum (XG) polymer concentration, mixing rate, and mixing time.…”