New Generation of "Green" Defoamers for Challenging Drilling and Cementing Applications

Abstract Increased environmental regulations in the North Sea, US and Canada offshores (OSPAR, US EPA, etc.) call for the use of less toxic and biodegradable chemicals in upstream oilfied applications. Compliance with international and domestic protocols governing use and discharge of oilfield chemicals is a crucial factor in the development of new, environmentally benign additives. To create competitive products, service companies need to re-evaluate their existing product lines and re-formulate with chemistries that must meet not only the standards for the ecotoxicity footprint but also, the technological challenges in oilfields. With increasing offshore production activities, the need to develop efficient technological solutions generates a substantial market for "green" chemical substances. In drilling and cementing applications, the reliable administration of defoaming chemistries is a key step in preventing excessive foaming and avoiding operational difficulties due to entrained air. Traditional products that are used in common operating conditions, often pose a risk to the environment. A new generation of "greener" chemistries is needed either in liquid or solid forms. Solid defoamers represent a particularly attractive alternative, as they are characterized by long term stability and ease of handling under severe climatic conditions. This paper presents the development of "green" technologies that show superior performance when compared to traditional defoamers. Formulated products in liquid and solid forms are evaluated using an advanced analytical approach to optimized performance during simulated field conditions. Based on widely used risk assessment models, these new alternatives offer safe and reliable solutions for slurry design and chemical control of foaming in offshore applications. Examples of severe foaming cases in slurries containing diverse additives are presented and demonstrate the advantage of this "green" technology. The oilfield industry is presently facing several challenges both from stricter environmental restrictions and also from specific field application requirements. The focus on finding suitable replacement additives for cementing and drilling systems without compromising the properties of completion fluids is a priority for many oil service companies. The studied "green" defoamers are less toxic and easily biodegradable thus providing new environmentally responsible and cost-effective additives.