The purpose of the study was to assess the impact of industrial wastewater on the concentration of methanol in the considered section of the Ob River basin, present proposals for the implementation of a new treatment system and analyse the implementation results. On the basis of the results of the analysis of the known methods for reducing the concentration of methanol in water, a new technological scheme for post-treatment of effluents using biological treatment with methylotrophic Methylomonas methanica Dg bacteria was proposed. The calculation of the dilution of treated wastewater using the “NDS Ecolog” program was carried out on the basis of the detailed calculation method of Karaushev, the results of which showed a decrease in the concentration of methanol in the control section to 0.0954 mg∙dm ^–3 (permissible concentration is 0.1 mg∙dm ^–3). During the period of the flood of the Glukhaya channel, it ceases to be a separate water body and, in fact, becomes part of the flood channel of the Ob River. Certain parts of the flooded areas, due to elevation changes, communicate with the channel only during a short period of time when the water level rises, i.e. 3–5 weeks during the flood period, and in fact remain isolated reservoirs for the rest of the time, potentially acting as zones of accumulation and concentration of pollutants.

The study examines the application of dry gas injection technology (cycling process) in different depletion stages (25%, 50%, 75%, 100% of the initial reservoir pressure, and the dew point pressure) at a gas condensate field. The injection took place with varying numbers of injection wells relative to production wells (4:1, 3:1, 2:1, 1:1, and 1:2). The study assessed the impact of dry gas injection periods, ranging from 1 to 3 years, on increasing the condensate recovery factor in a real gas condensate reservoir named X. A hydrodynamic model was used and calibrated with historical data, resulting in a comprehensive approach. Compared to the traditional depletion development method, this approach led to a significant 9% rise in the condensate recovery factor. The results indicate that injection has a positive effect on enhancing the recovery factor of condensate and gas when compared to primary development methods based on depletion. As a result, these findings facilitate a rapid evaluation of the possibility of introducing similar measures in gas-condensate reservoirs in the future for reservoir systems that have a low and moderate potential for liquid hydrocarbons C5+. The optimised multidimensional hydrodynamic calculations, utilising geological and technological models, are crucial in determining the parameters for the technological production and injection wells.