Improvement of acid treatment on bottomhole zone

The article focuses on optimizing acid treatments for the wellbore zone, considering the geological and lithological characteristics of the formation. The geological and lithological characteristics of the deposits in the OGPDs of the «Azneft» PU were investigated, and the selection of acids was justified depending on the lithological composition of the deposits. By conducting laboratory studies, the effect of acid compositions on cuttings samples taken from different horizons was studied, the optimal acid composition and volume were selected, and the mutual effect of their compositions with formation fluids was determined. The study of the effect of acid compositions on cuttings samples taken from the 600-640 m depth of the GA horizon of the «Absheronneft» OGPD showed that compositions with a low content of hydrofluoric acid in the composition had a better effect on the decomposition of cuttings. Thus, since the samples were decomposed and dispersed when affected by these compositions, the penetration of the acid into the rock sample was facilitated and the mass loss was higher. The research also indicated that compositions containing organic acids were particularly effective in breaking down the rock samples. The presence of organic acids appears to enhance the dissolution and disintegration of the rock, making them a promising choice for acid treatments. Laboratory experiments conducted on drilling cuttings from the Pirallahı field of «Absheronneft» OGPD have shown that the best permeability recovery is achieved with a solvent mixture consisting of 6% HCl and 2% HF, resulting in a 37% recovery. Keywords: acid treatment of the bottomhole zone; wellbore zone; chemical solvent compositions;