The article considers theoretically, on a qualitative level, the rates of filtration and decomposition of ammonium nitrate, depending on the time of heat release and on the rate of nitrate entry into the porous space of the reservoir near the perforations. It is assumed that field tests at different rates of nitrate solution injection into the well will yield quantitative data on filtration, heat transfer and kinetics of heat release in the reservoir. To estimate the temperature increase in the reservoir under the action of the binary mixture reaction (nitrate + oxidant), the temperature was calculated when the nitrate was decomposed in an aqueous solution (300 g of water per 1 kg of nitrate), taking into account the oxidation of a small fraction of oil in the reservoir near the well with oxygen released during the decomposition of nitrate.