METHOD FOR THERMOCHEMICAL TREATMENT OF OIL CARBONATE FORMATION FOR PRODUCTION OF HIGH-VISCOSITY OIL AND DEVICE FOR ITS IMPLEMENTATION Russian patent published in 2022 - IPC E21B43/24 E21B36/04 

FIELD: oil industry.

SUBSTANCE: group of inventions relates to the oil industry. In the method of thermochemical treatment of an oil carbonate formation for production of high-viscosity oil, a tubing string is lowered into the well and fixed in the perforation zone. Then electric heating elements are switched on to heat downhole heater-reactor to temperature from +100 °C to +500 °C. At the same time oxidizing agent is pumped into downhole heater-reactor from the row: air oxygen, air, steam-air mixture in ratio steam : air = from 1:1 to 2:1. In parallel, a composition for producing an oxidate is pumped into the downhole heater-reactor: either a hexane fraction or a broad fraction of light hydrocarbons BFLH, or organic solvents, which are a mixture of liquid hydrocarbons. Temperature and pressure are monitored according to the values of the corresponding sensors, by the sharp jump of one of which the beginning of the oxidative reaction is determined and a decision is made on switching off the electric heating elements. Further, the well is held in a closed state for 12 hours to 7 days. Temperature and pressure transducers are used to determine the following stage: either additional injection of BFLH and air, or extraction of finished product. Device is not disassembled and lifted to the surface, but separate injection of the required reagents and extraction of the finished product are carried out. Device for implementing said method comprises external tubing string of large diameter 73–114 mm, inside which inner tubing string of small diameter 27–60 mm is located coaxially. Throughout the length of the inner tubing string, process fluids supply tubes, a power cable and wires to the sensors, a hydroflange assembly are attached by means of reinforced clamps, adapter coupling from hydroflange with sealed inputs of tubes and wires for heat-resistant electric power supply cable and heat-resistant data transmission wires. To the hydroflange there is an adapter coupling from a deep heater-reactor, a transition coupling for inlet of process reagents or air. Downhole heater-reactor is equipped with built-in valves and device for fastening additional tubes for inlet of process liquids, sealed lead-ins for input of power cables and wires for sensors, heat-resistant housing, inside of which there is a reactor zone filled with thermo- and chemical-resistant filler, with electric heating elements arranged along the whole length of the reactor zone.

EFFECT: intensification of oil production, improvement of technology of thermochemical action, energy saving, protection of equipment, prevention of unauthorized chemical reactions.

4 cl, 6 ex, 2 dwg