作者
E. Kakadjian,Sivaram Pradhan,Edgar Gutiérrez,Megan Pearl
摘要
Abstract The accumulation of organic deposits poses a significant challenge to oil and gas production. This phenomenon alters the permeability and wettability of formations, which in turn hampers the flow of crude oil, leads to interruptions in production, causes damage to equipment, and diminishes overall operational efficiency. The efficacy of traditional remediation treatments, like organic solvents, can be highly variable and often must be revised with incomplete deposit dissolution. This paper presents a water-based treatment that combines biosurfactant with environmentally friendly solvents in all-in-one microemulsion to offer a BTEX-free paraffin remediation technology. Multifunctional microemulsions containing biosurfactants, co-surfactants, and green solvents were assessed for phase stability in a wide range of temperatures, and top formulation was evaluated in organic deposits from two US-extended oil and gas reservoirs. Deposits were characterized by High-Temperature GC (HTGC) and Wax Appearance Temperature (WAT). The dissolution and dispersion behavior of organic solids was studied by a dynamic paraffin dispersion test (DPDT) in hot and freezing conditions using distilled water and seawater. Dispersed paraffin was further analyzed by microscopy, and dispersion was determined by gravimetry. This all-in-one microemulsion formulation exhibited enhanced dispersion of heavy organic deposits in water, outperforming alternative solvents. The clustered paraffin was destabilized and dispersed smaller than 200 m paraffin particles by the penetration of the biosurfactant and the bio-solvent, increasing the effective surface area and facilitating increased mass transfer of paraffin into the aqueous phase. Furthermore, it notably altered surface wettability from oil-wet to highly water-wet, which helped prevent subsequent redeposition and agglomeration of paraffin. In addition to this performance, the water-based paraffin dispersant microemulsion creates an instable slurry that enables transport of paraffin particles for removal from wellbores and pipelines through regular flow. Once agitation ceases, these particles can be easily separated and collected from the carrier fluid. The ability of the biosurfactants to penetrate, disperse, and suspend solid particles or accumulated materials, known as the biosurfactant trifecta, significantly accelerated the breakup of bulk organic masses. Adding the bio-solvent offered solvency without the toxicity associated with commonly used BTEX solvents. Ultimately, integrating biosurfactants with bio-solvents resulted in superior dissolution capabilities for organic deposits. This study presents a novel all-in-one water-based paraffin dispersant solution consisting of a microemulsion constituted by bio-solvent and biosurfactants. Results show this formulation's efficacy in dispersing the hardest and highest molecular weight wax deposits into smaller particle sizes that easily remain suspended and dispersed. Adopting a high-performing, water-based system addresses environmental concerns related to biodegradability, toxicity, and safety.