RATIONALE FOR THE USE OF A HYDRATE FORMATION INHIBITOR IN PRODUCTION WELLS IN WESTERN SIBERIA

Operation of the gas transmission system under hydrate conditions leads to the risk of deposits, changes in operating modes and plugging of pipelines and gas transmission equipment. Inhibitors such as methanol and glycols are mainly used to prevent hydrate formation. Less commonly, small amounts of polymer compounds (kinetic inhibitors) are used, which instead of inhibiting formation work thermodynamically, slowing the rate of formation of gas hydrates. However, the problems associated with excessive methanol consumption and the production of products that do not meet the standards for the content of dissolved methanol remain unresolved. These problems can be solved by improving the technological scheme of gas collection and treatment. The article focuses on the use of methanol as a hydrate inhibitor, which effectively prevents this process. It has been shown that in order to optimize the flow rate of methanol, it is necessary to take into account the salinity of formation water. The urgency of the problem is due to the high risks for the normal operation of wells, since gas hydrates can lead to clogging of equipment and pipelines, which in turn can cause emergencies and shutdown of the entire production. The article describes the current status of field development in Western Siberia, including an analysis of reserves and an assessment of production potential. Seven pay zones have been identified in the field, two of which are associated with the Upper Cretaceous deposits, four with the Upper Jurassic and one with the Middle Jurassic. The authors proposed a method for calculating the optimal amount of methanol required to prevent the formation of gas hydrates. The calculations are based on data on the composition of Cenomanian gas, temperature and other conditions in the field under consideration. The study identified critical points where gas hydrates are most likely to form. This made it possible to accurately calculate the required amount of methanol to maintain the hydrate-free state of the wells. The results of testing in the field of Western Siberia showed that the dosing of methanol is an effective means to prevent hydrate formation.