The oil fields of Azerbaijan are mainly composed of poorly cemented and loose rocks. Most of these fields have already entered the final stage of development, characterized by a high water cut. At this stage of development, the problems associated with sand and water production of wells are exacerbated. In addition, though that relict (primary) hydrogen sulphide is not present in the composition of reservoir oil in Azerbaijan's fields, biogenic hydrogen sulphide (hydrogen sulphide of secondary origin) is observed in the production of many producing wells. It is also possible to contaminate a productive formation as a result of the gradual decomposition of a number of reagents (polymers and lignosulfonates) contained in process fluids (drilling fluids, killing fluids, etc.) by sulfate-reducing bacteria. As a result, in the process of oil production, serious complications arise associated with the high corrosiveness and toxicity of hydrogen sulfide. In this regard, there is a need for a more thorough study of hydrogen sulfide and identifying the degree of its destructive effect in the process of oil production. The greatest danger from the whole variety of corrosive formation fluids is hydrogen sulfide and carbon dioxide. They cause intense corrosion damage to both downhole equipment and plugging stone, which is a barrier against sand and formation water. As a result of studies of the interaction of cement stone with hydrogen sulfide dissolved in formation water, it was found that during thermodynamic processes, the cements used do not provide a stable cement stone. The buffer layer inside the cement stone has a higher permeability and to a lesser extent prevents the transfer of aggressive substances into the depth of the cement stone and calcium hydrosulfate into the near-wellbore zone, which leads to intensive destruction of the stone. It is noted the need to continue the study of physicochemical factors affecting the rate of corrosion of cement stone in order to establish a quantitative relationship between the factors and determine methods for increasing the corrosion resistance of stone.
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