Preparation and Characterization of Colloidal Gas Aphron based Drilling Fluids Using a Plant-Based Surfactant

Abstract

Colloidal gas aphron (CGA) based drilling fluids, because of their non-coalescing nature, excellent capability in minimizing deep invasion, and also behaving like a flexible bridging material, are indicated for drilling permeable and fractured formations. Their unique feature is to form a solid free, tough, and elastic internal bridge in pore networks or fractures to minimize deep invasion by means of air microbubbles, which can be removed easily during the initial stage of production. CGA based fluids combine certain surfactants and polymers to create the system of microbubbles. Surfactant is used to produce the surface tension to contain the aphron as it is formed, build the multilayer bubble wall, and create interfacial tension to form a non-bonding network capable of bridging openings in permeable and fractured formations. Polymer is used as viscosifier and aphron stabilizer. The surface activity and aggregation behavior of the surfactant affects the stability and also other physico-chemical properties of generated microbubbles. Therefore, selection of a suitable surfactant is important for the generation of microbubbles with the desired rheological and filtration properties. The goal of this paper is to investigate the potential use of a new plant-derived surfactant as an aphronizer surfactant in preparation of CGA based drilling fluids for accomplishing desirable rheological and filtration properties. For this purpose, natural surfactant obtained from leaves of special tree namely Zizyphus Spina-Christi and used for preparation of aphron-based fluids. To evaluate the potential use of new plant-derived surfactant as an aphronizer, various physico-chemical properties of aphron-laden muds were investigated. To achieve the research objectives, laboratory tests of suspension generation, microscopic visualization, initial yield, filtration loss, and rheological behavior with varying concentrations of surfactant and polymer were performed. Effect of base fluid viscosity and surfactant concentration on size/size distribution of microbubbles, rheology, and yield of CGA based drilling fluids will be presented. Three rheological models, namely, Bingham Plastic, Power Law and Casson models were used for characterizing rheological properties of the muds studied.

Experimental Investigation of Water Based Colloidal Gas Aphron Fluid Stability

“…The S/N ratio response of this parameter is 33.26 which is the maximum value. XG shows a better performance in increasing fluid stability compared to PacR; XG has been used as Aphron stabilizer in many research and outperformance has been also reported [4,26,27]. The effect of surfactant type on stability is lower than other parameters.…”

Effectiveness of Colloidal Gas Aphron Fluids Formulated with a Biosurfactant Enhanced by Silica Nanoparticles

“…Starch and Xanthan Gum (XG) are frequently used as biopolymers for GCA-based fluids [43,61]. XG is a high-molecular-weight polysaccharide [62] with stabilizer and viscosifier attributes suitable for use in drilling fluids [46,47]. In particular, XG's viscosification contributions to CGA-based fluids are well known in providing them with stability [31].…”

“…Arabloo et al (2012b) evaluated the properties of CGA-based fluids formulated using a surfactant derived from plant material. They established that bubble size in such fluids increases as surfactant concentrations increase [46]. Ziaee et al (2015) reported that the rheological characteristics of CGA-based fluids were more accurately predicted by the Herschel-Buckley model than other models [47].…”

Modeling of micro-bubble surfactant multi-layer drilling fluid stability based on single bubble behavior under pressure and temperature in a deviated gas well

“…There are more experiments on Aphron properties (Lamb and Stuckey, 2000;Wang et al, 2000;Scarpello and Stuckey, 1999;Matsushita et al, 1992); however, limited studies have been performed on mass transfer mechanisms and stability modeling of the MBSML bubbles (Lye and Stuckey, 2001). It has been shown that the mixed surfactant such as SDS þ Span20 and SDBS þ Span20 could generate stable Aphrons (He et al, 2006); also, several planet-based surfactants are suggested for stable micro-bubble preparation (Arabloo Nareh'ei et al, 2012). In this work, the suggestion by He.…”