During field development with the use of reservoir pressure maintenance systems, the filtration characteristics of the bottom-hole zone (BHZ) deteriorate over time. The purpose of the work is to select an effective technology for treatment of BHZ of injection wells exploiting low-permeability terrigenous reservoir by conducting a set of studies. The composition of the main colmatants was determined and the risks of carbonate salts precipitation in downhole conditions were assessed. Three main types of colmatant introduced by injected water were identified for the objects under consideration: solid suspended particles, residual oil products and inorganic salts, precipitated from injected water due to changes in thermobaric conditions and mixing with various incompatible technological fluids. The list of reagents potential for application to restore the permeability of the BHZ depending on the type of colmatant has been compiled. Filtration experiments on the impact of acid compositions, solvents and surfactants on the core have been carried out. It was determined that the recovery of permeability of rock samples is best provided by application of the technology including sequential injection of solvent and compositions based on hydrochloric and mud acid. Recommendations for treatment of BHZ of injection wells in the conditions of the considered objects were developed.
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