Abstract
In order to systematically study the rheological and morphological characteristics of foam fracturing fluid, hydroxylpropyl guar (HPG) was selected as the foam stabilizer, sodium dodecyl sulfate (SDS) and cetyl trimethyl ammonium bromide (CTAB) were selected as the foaming agents, and foam fracturing fluid used for coalbed methane (CBM) stimulation was prepared. The viscosity, quality and half-life of foam fracturing fluid under different additive concentration levels were tested, and the bubble morphology and its relationship with half-life were observed and quantitatively analyzed with microscopy. In addition, the influence of pulverized coal on foam stability was also studied. The results show that the influence of pulverized coal on the basic parameters of the foam fracturing fluid correlated with the particle size and concentration of the pulverized coal. The small particle size of pulverized coal increased the liquid phase viscosity and half-life of the foam, but reduced the foam quality. With increasing pulverized coal concentration, the effects were enhanced. The average bubble diameter decreased with increasing HPG concentration, and the changing trend of the bubble diameter conformed to the gamma distribution. The foam half-life had a positive and negative correlation with the bubble morphology parameters alpha and beta, respectively. The results can deepen the understanding of the influence of foaming agents, foam stabilizers, and coal particles on the properties of foam fracturing fluids, and provide a reference for the optimization of foam fracturing fluid formulations.
NSTL
Elsevier