New Opportunities for the Drilling Industry Through Innovative Emulsifier Chemistry

Abstract

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractAs the drilling industry operates in more stringent environmental constraints and conservative economical environment, the industry is poised to take advantage of innovative emulsifiers for new opportunities in solving the environmental problems and offer economical advantages over conventional invert emulsion drilling fluids. We have developed various innovative invert emulsion drilling fluids using novel emulsifiers. These systems provide a quantum leap in new drilling fluid technology in solving environmental problems while offering economical advantages over conventional invert emulsion drilling fluids.Since, the inception of invert emulsion drilling fluids decades ago, emulsifier technology for these systems has not advanced much. The focal points in development in past history have been in base fluids, O/W ratios and some in weight materials, however very little has been changed in emulsifier chemistry. Only step-changes in technology have been achieved with changes in base-fluids and other parameters of invert emulsion drilling fluids. It is time to move on. Using innovative emulsifier chemistry has produced novel invert emulsion fluids, which address the environmental as well as performance and cost-related issues in drilling operations.This paper discusses the systematic design, development and testing of novel emulsifiers for innovative invert emulsion drilling fluids. The overall impact of manipulation of emulsifier chemistry in invert emulsion drilling fluids to meet the environmental and functional requirements of drilling operation is presented. The formulations and applications of lime-free high temperature invert emulsion drilling fluid, negative alkalinity ester-based fluid, and reversible invert emulsion drilling fluids in laboratory experiments as well as field trials are highlighted.

Wetting alteration of mica surfaces with polyethoxylated amine surfactants

“…Since commercial blends of surfactants were used in those studies, the actual chemical structures of the surfactants were not known. Patel and Ali (2003) suggested the use of ethoxylated amines as emulsifiers in drilling muds because it is possible to change their hydrophilic-lipophilic balance (HLB). Being able to manipulate the HLB value would allow one to alternate between an invert water-in-oil and oil-in-water emulsions.…”

Cleanup characteristics and mechanisms of reversible invert emulsion drilling fluid

“…These molecules are reversible; that is, they are strong invert emulsifiers in the presence of a base but become regular emulsifiers in the presence of an acid ( Fig. 1) (Patel and Ali, 2003). It has been reported that this reversibility allows the drilling fluid to change from an invert emulsion, i.e., water-in-oil, to a regular emulsion, i.e., oil-in-water, at different stages of the drilling/completion operation.…”

“…During drilling, the drilling fluid can be used as an invert emulsion with all the performance benefits associated with oil-based muds (OBMs). During and after the completion stage, the emulsion can be reversed by adding a water-soluble acid, thus providing excellent filter-cake cleanup, better cementing, improved production in well completion, efficient cutting cleanup, and waste minimization (Ali et al, 2004(Ali et al, , 2006Green et al, 2001;Patel, 1999;Patel and Growcock, 1999;Patel and Ali, 2003). Because the unique attribute of RIEM in the completion of a well is supported by the pH-responsiveness of ethoxylated alkylamine emulsifiers, it is important to explore how pH levels influence the interfacial gathering behaviors of the emulsifiers and thus the completion performance of RIEM.…”

“…A limited number of publications on this topic can be found in the literature. Several authors (Ali et al, 2004(Ali et al, , 2006Green et al, 2001;Patel, 1999;Patel and Growcock, 1999;Patel and Ali, 2003) reported that low pH promotes the transformation of RIEMs from a water-in-oil type to an oil-in-water type, inducing the water wetting condition of the surfaces of the pipes and the drilled formation. Bryant et al (2006) has demonstrated that the adsorption of ethoxylated alkylamines affects the wettability of mica surfaces.…”

Wettability and Prediction of Oil Recovery From Reservoirs Developed With Modern Drilling and Completion Fluids

“…Since commercial blends of surfactants were used in those studies, the actual chemical structures of the surfactants were not known. Patel and Ali (2003) suggested the use of ethoxylated amines as emulsifiers in drilling muds because it is possible to change their Hydrophilic-Lipophilic Balance (HLB). Being able to manipulate the HLB value would allow one to alternate between an invert emulsion (water-inoil) and an emulsion (oil-in-water).…”