RU-2861634-C1 - THERMO-ULTRASONIC COUPLING FOR PREVENTING ASPHALTENE-RESIN-PARAFFIN DEPOSITS IN PRODUCTION WELLS

Abstract

FIELD: oil and gas industry. SUBSTANCE: invention relates to downhole devices for preventing asphaltene-resin-paraffin deposits (ARPD) in lift strings of flowing and mechanised wells, and can be used in deviated wells. A thermo-ultrasonic coupling for preventing ARPD deposits in production wells comprises at least one temperature sensor of the axial channel wall, an vibroacoustic sensor, a controlled heating element for regulating heat supply, a body provided with an axial through channel and threaded ends. The coupling includes a passive heat transfer element configured to receive heat from downhole equipment and transfer heat to the axial channel wall. A thermoelectric generator is connected on the hot side to the passive heat transfer element. The cold side of the thermoelectric generator is heat-transfer connected to the annulus or casing string through a radiator. The coupling comprises an electronic control module and an annular ultrasonic unit acoustically connected to the axial channel wall through a contact belt. The thermoelectric generator is configured to transmit electricity to the electronic control module and the ultrasonic unit. The electronic control module is configured, based on sensor signals, to control the modes of the ultrasonic unit. The coupling is equipped with retaining casings. EFFECT: reduction of the rate of ARPD formation. 2 cl

Inventors

• Titova Tatiana Alekseevna

Dates

Publication Date

20260506

Application Date

20250917

Claims (2)

1. 1. A thermo-ultrasonic coupling for preventing deposits of asphalt, resin and paraffin substances in production wells, comprising at least one axial channel wall temperature sensor and a vibroacoustic sensor, a controlled heating element for regulating heat supply, a housing provided with an axial through channel and threaded ends, characterized in that it contains a passive heat transfer element configured to receive heat from the well's submersible equipment and transfer heat to the wall of the axial channel, a thermoelectric generator connected to the passive heat transfer element on the heating side, and the cold side of the thermoelectric generator is heat-transferably connected to the annulus or casing through a radiator, an electronic control module, an annular ultrasonic unit acoustically connected to the wall of the axial channel through a contact belt, wherein the thermoelectric generator is configured to transfer electrical energy to the electronic control module and the ultrasonic unit, and the electronic control module, based on sensor signals, is configured to regulate the modes of the ultrasonic unit, wherein the coupling is equipped with retaining casings.
2. 2. The coupling according to paragraph 1, characterized in that the temperature sensor is located on the side of the wall of the axial channel in the housing seat with a heat-conducting gasket, and the vibroacoustic sensor is on the outer surface of the housing in the installation area of the ultrasonic unit.

Description

Field of technology The invention relates to oil production, namely to downhole devices for preventing asphalt-resin-paraffin deposits (ARPD) in the tubing strings (TC) of flowing and mechanized wells, primarily with electric centrifugal pumps (ECP), and can also be used in wells with sucker rod pumps (SRP) and directional wells. State of the art A device for preventing the formation of asphaltene-resin-paraffin and hydrate deposits in oil wells is known (patent RU 2594910C1). The device for preventing the formation of asphaltene-resin-paraffin and hydrate deposits in oil wells comprises a heat generator connected via a suction and discharge pipeline of a circulation pump to a well heater, which is an integral part of the tubing. The heater is a housing consisting of outer and inner walls installed coaxially with an annular gap and forming a cavity for a heating coolant, an inlet and outlet manifold with nozzles, in the inner cavity of which an additional heat exchange element is installed. The additional heat exchange element is designed as two cylindrical shells installed coaxially and connected to each other. At the ends of the additional heat exchange element, pylons are located in which channels for the supply and outlet of the heating coolant are formed. Disclosure of the essence of the invention The objective of the invention is to ensure long-term, autonomous and safe prevention of ASPD by means of combined thermal and ultrasonic action in the deposit formation zone without supplying surface energy and without deteriorating the hydraulic characteristics of the elevator column. The technical result consists in reducing the rate of formation of asphaltene-resin-paraffin substances. A thermal-ultrasonic coupling for preventing asphaltene, resin, and paraffin deposits in production wells comprises a housing with an axial through-channel and threaded ends. The inner surface of the axial channel has a nickel-phosphorus-based anti-adhesive coating. The coupling also contains a passive heat transfer element designed to receive heat from the well's downhole equipment and transfer it to the wall of the axial channel through good thermal contact and high thermal conductivity: a metal insert/heat pipe brazed to the heat-extraction zone. A thermoelectric generator (TEG) is connected to the passive heat transfer element on the heating side, and the other side is connected to the well's environment. One side of the TEG is equipped with a temperature differential amplification unit, including radial fins or an ejector heat exchanger. The electronic control module is equipped with a power path. The annular ultrasonic unit is comprised of at least four sector piezoelectric elements acoustically matched to the axial channel wall via a contact belt. The annular ultrasonic unit is acoustically coupled to the axial channel wall with a sound emission frequency of 15–120 kHz. The thermoelectric generator (TEG) is formed by a matrix of thermoelectric modules based on Bi2Te3 or its solid solutions, electrically connected to generate the required current and voltage. The TEG is configured to transmit electrical energy to the electronic control module (ECM) and the ultrasonic unit. The ECM contains a DC-DC converter and a buffer energy storage device (a supercapacitor or battery). The ECM is configured to excite the ECM or regulate heat supply in deposit prevention and de-scaling modes using sensor signals. The coupling is configured to allow flow to pass in the event of failure of the active elements of the unit. The passive heat transfer element comprises at least one heat pipe or heat-conducting insert with a capillary structure, installed between the heat collection zone and the heat transfer zone to the wall of the axial channel. The design of the active components eliminates blockage of the passage; in the event of any failure, at least 95% of the nominal flow area is maintained, and the casings contain any possible fragments. When signs of deposit buildup are detected, the electronics first increase the temperature at the wall (softening), then emit a series of ultrasonic pulses with a frequency sweep to break it down. The cold side of the thermoelectric generator transfers heat to the annulus and/or casing through a radiator (finning/heat exchanger). The temperature sensor is installed near the wall of the axial channel in a heat-conducting contact; the vibroacoustic sensor is attached to the coupling body near the ultrasonic unit. The coupling is screwed into the wellbore string and positioned within the heat-exchange zone of the downhole equipment (motor, pump, power module). The passive heat transfer element is installed with thermal contact to the heat source and to the wall of the coupling's axial through-hole channel. The cold side of the thermoelectric generator (TEG) is connected to the outer surface of the coupling body, which exchanges heat with the annular fluid (casing and/or annular fluid). The annular ult