METHOD OF STABILIZATION OF HEAT STATE OF WELLHEAD ZONE ION PERMAFROST ROCKS

摘要

FIELD: oil and gas producing industry; applicable in completion and operation of oil and gas fields in zone of occurrence of permafrost rocks. SUBSTANCE: method includes installation in well of cooling system which consists of naturally acting small-diameter thermostabilizers located inside heat-transmitting tubular containers; removal of heat coming from well into environment. Tubular containers are arranged in two internal and external circular circuits round well. Internal circuit is located directly behind guide tube inside cement circle. External circuit is arranged inside rock mass at distance from well equalling half of maximum calculated radius of thawing aureole of rocks round well not equipped with cooling system which is calculated on basic of solution of Laplace unidimensional equation written in cylindrical coordinates by methods of numerical simulation, for instance, by finite difference method. Number of tubular containers in circuits is determined by design of temperature field on the basis of computation by numerical methods in Cartesians coordinates of two-dimensional nonstationary equation of heat conduction in heterogeneous medium with movable phase boundary describing heat interaction of well, cooling system and surrounding rocks. Mathematical relationships are offered. EFFECT: efficient stabilization of heat state of wellhead zone in permafrost rocks and preset operate reliability. 4 dwg