In the conditions of the Far North, the construction and operation of oil and gas wells on permafrost soils is associated with the possible manifestation of dangerous technogenic processes that require solving issues of ensuring operational reliability and longitudinal stability of wells, as well as reducing the negative impact on the ecological and geocryological situation during operation. The key factor is the thawing of permafrost soils in the wellhead zone. Production wells, from the moment they start their operation until its completion, continuously have a significant thermal effect on the enclosing permafrost soils. To reduce the negative thermal impact from production wells at oil and gas production fields located in the conditions of the distribution of permafrost, as a rule, passive methods of temperature stabilization of soils are used, in particular, thermally insulating directions or thermally insulated lift pipes.
In order to reduce the negative thermal impact on the soils of the wellhead space of production wells, the authors proposed to cover the elements of the direction, conductor or technical column with ultra-thin thermal insulation to the entire depth of the permafrost. Depending on the conditions of construction, ultra-thin thermal insulation is proposed to be applied to the conductor of a production well (new construction) or tubing (existing fund). The described technical solution makes it possible to significantly reduce the heat flux transmitted to permafrost soils to the entire depth of their occurrence. The efficiency of using a liquid composite heat-insulating material is confirmed by the results of predictive heat engineering calculation. The solution of the problem is carried out by preparing a model and obtaining a forecast of changes in conditions that simulate the process of operating a production well, taking into account geology, external climatic factors, and technical characteristics of the heat-insulating material. According to the results of mathematical modeling, the use of ultrathin liquid thermal insulation to cover elements of a production well in terms of the effectiveness of thermal insulation properties is comparable to the use of such measures as the installation of thermally insulating wellheads or thermally insulated lift pipes. This method is easy in implementation and has obvious economic advantages.
References
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