Espina Corona Gum (ECG) As a Polymeric Additive of Water-Based Drilling Fluids (WBMs)​

YURANY VILLADA; TAVERNA, MARÍA E.; SEBASTIÁN GILETTA; NATALIA CASIS; DIANA ESTENOZ

Workshop; VII Summer School: The role of conventional and unconcentional resources in energy transition; 2021

Water-based drilling fluids (WBMs) perform important roles in oil and gas rotary drilling operations. WBMs are usually designed as shear-thinning non-Newtonian fluids, which exhibit high viscosity at low shear rates to suspend or transport drill cuttings to surface, and low viscosity at high shear rates to enable easy pumping into the wellbore (Balding et al., 2020; Li et al., 2018). In addition, WBMs fulfil other functions such as cooling and lubricating the drilling bit, minimizing the formation damage, controlling formation pressures, and forming low-permeability filter cake that seals pores (Caenn et al. 2017). In recent years, several studies have been reported on the design of WBMs with low toxicity level, and low cost. In this context, natural and synthetic polymers have achieved interest in the drilling processstage. In particular, polysaccharides such as guar gum (GG) is widely used as viscosity enhancer additive in the oil industry. However, most of GG consumed in South America is imported from India, Pakistan, United States, Australia, South Africa, and Sudan.Espina corona gum (ECG) is a polysaccharide extracted from the seeds of Gleditsia amorphoides trees that grow in South American countries. Structurally, ECG is similar to GG, which has a mannose/galactose ratio of 2 (Perduca et al., 2013). Due to their properties, the ECG has been used mainly in the food industry as a viscosifier, gelling agent, and stabilizer (. In particular, Hiriat et al., ( 2017) studied the replacement of GG by ECG in the production of spreadable cheeses.. Despite of its wide application in the food area, its use in WBMs has not yet been studied.In this work, the replacement of GG by ECG in WBMs was investigated. Both biopolymers were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), steady and oscillatory shear analysis, Z potential; and intrinsic viscometry determinations. To evaluate the replacement, two different simple WBMs systems were designed: S-GG (BT/GG/PAC/H2O) and S-ECG (BT/ECG/PAC/H2O). The WBMs were characterized by rheological, filtration, thermal and structural tests. Sisko and Herschel Bulkey models were employed to theoretically describe the rheological behavior.The results showed that the fluids containing ECG exhibited superior rheological properties (higher shear-thinning behavior, higher plactic viscosity, and higher yield stress), a better filtration performance (lower filtrate volume and thinner, more compact, and less permeable filter cake) and higher thermal stability.ECG promises an innovatively, renewable, non-toxic, biopolymer alternative to partial or total replacement of GG in WBMs.