Recently, interest in on-site heat generation has increased due to injection of thermochemical fluids as a complex effect on well productivity. The method of thermochemical treatment with H₂O₂ while restoring and increasing the filtration characteristics of the bottomhole formation zone is a relatively new and insufficiently studied technology. The article discusses the key factors affecting the exothermic decomposition of this fluid when this fluid is injected into the well. The heat effects, pressure growth and decomposition time of H₂O₂ were determined depending on the salinity of the water, the composition of terrigenous rock, and various concentrations of H₂O₂. Physical 1-D modeling of H₂O₂ injection was carried out on rock models with mobile and stationary oil, which demonstrated a sharp increase in temperature by 100–240 °C caused by the decomposition of H₂O₂ due to the catalyst and the presence of catalytic active sites in the rock. As a result of this thermochemical treatment, the rock was partially cleaned of immobile oil and heavy sediments. Injection of H₂O₂ with a catalyst has shown the effectiveness of displacement of mobile oil from the filled sand model. Thus, the results of this study can provide a preliminary assessment of the effectiveness of H₂O₂ thermochemical treatment in fields operated at a later stage of development.

Currently, most explored oil fields in Russia are at a late stage of development, and in order to maintain high levels of oil production, it is rational to put into operation fields with hard-to-recover reserves. For complicated oil fields, in particular fields with high-viscosity oil, the known traditional methods of development are ineffective. Therefore, the search for new technologies for the development and operation of such fields to significantly increase oil recovery and intensify production is of fundamental importance. One such method of heat treatment of the bottomhole formation zone is the use of heat and gas generating systems on site. In this work, new results were obtained on physical modeling of thermochemical reaction initiation with delayed-action catalyst (2,2-bis(hydroxymethyl)butanoic acid) filtration tests on composite core models of sandstone and carbonate with foam heat generation and initiating additives of binary type. Using hydrodynamic modelling, the results of laboratory studies were reproduced, and the preliminary efficiency of the developed technology for thermochemical treatment of deposits in the Samara region (Russia) was evaluated.