The Effect of Chemistry and System Conditions on Hydrate Interparticle Adhesion Forces Toward Aggregation and Hydrate Plug Formation

Abstract

Abstract The adhesion force between two cyclopentane hydrate particles was directly measured using an improved micromechanical force apparatus. Adhesion forces decreased between 22 and 87% with the addition of approximately 1000 ppm of various carboxylic acid derivatives. The effect of simple, saturated carboxylic acids (such as decanoic acid) may be primarily explained by a decrease in water-oil interfacial tension. More complex carboxylic acids, such as L-lysine and D-tyrosine amino acids, migrate slowly to the water-oil interface and subsequently may be ineffective at weakening the capillary water bridge between hydrate particles in the 30-second formation/destruction timescale. A 4-membered polynuclear aromatic carboxylic acid (1-pyreneacetic acid) exhibited a decreased adhesion force larger than the prediction from decreased interfacial tension, suggesting an alteration in hydrate surface wettability. We present a numerical solution of one hydrate slurry viscosity model for a simple pipeline scenario, where the difference in adhesion force between mineral oil and 1-pyreneacetic acid can shift shear requirements by one order of magnitude.