Slidably Positioned RF Transmission Line for Subterranean Heating

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional hydrocarbon resource recovery methods, such as Steam-Assisted Gravity Drainage (SAGD), face inefficiencies due to heat loss, high steam consumption, environmental impact, and limitations in permafrost regions, while RF heating systems suffer from impedance mismatches leading to inefficiencies as the subterranean formation heats up.

Innovation Solution

A method and apparatus that involves positioning a tubular conductor with a dielectric section within a wellbore, slidably inserting an RF transmission line to couple with the conductor, and supplying RF power to heat hydrocarbon resources, allowing for impedance adjustment by replacing the transmission line as needed, and optionally flowing fluids to control temperature and pressure.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If SAGD process is used to heat heavy oil, then oil viscosity is reduced and production efficiency is improved, but heat loss to surrounding formation increases and steam consumption becomes excessive

Engineering Contradiction:

Improveoil production efficiencyVSAvoidheat loss

Core Design Contradiction:

ProductivityVSLoss of energy

Solution Approach 1:

The patent replaces the thermal convection mechanism of SAGD (steam injection and heat transfer through formation) with direct electromagnetic RF heating. The RF transmission line delivers electromagnetic energy that directly heats the heavy oil and formation rocks through dielectric heating, eliminating the need for steam injection and the associated heat losses to surrounding formation.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces an RF transmission line as an intermediary device to deliver heating energy directly to the target zone. This transmission line acts as a conduit for electromagnetic energy, positioning it within the wellbore to provide localized heating without the thermal diffusion losses characteristic of conventional steam-based methods.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Use of energy by moving object

If RF transmission line is positioned within wellbore to deliver power, then heating efficiency is improved, but impedance mismatch occurs as formation heats up

Engineering Contradiction:

Improveheating efficiencyVSAvoidimpedance matching

Core Design Contradiction:

Use of energy by moving objectVSReliability

Solution Approach 1:

The patent implements a dynamic impedance matching solution where the transmission line system can adapt to changing formation conditions. As the formation heats up and its electrical properties change, the system maintains optimal power transfer by adjusting impedance parameters, ensuring continuous efficient operation throughout the heating process.

Inventive Principle:

Principle #15Dynamics

3Device complexity

If conventional well production methods are used for highly viscous hydrocarbons, then equipment simplicity is maintained, but production capability is lost due to oil immobility

Engineering Contradiction:

Improveequipment simplicityVSAvoidproduction capability

Core Design Contradiction:

Device complexityVSProductivity

Solution Approach 1:

The patent replaces mechanical production methods (which rely on natural pressure or pump mechanics) with electromagnetic heating. By heating the heavy oil to reduce its viscosity, the oil becomes mobile and can flow naturally to production wells without requiring complex high-pressure injection equipment or powerful pumping systems.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach enhances hydrocarbon resource heating efficiency by minimizing heat loss, reducing steam consumption, and enabling cost-effective operation, including in permafrost regions, through adjustable impedance and efficient RF power delivery.

Implementation Method 1

hydrocarbon resource recovery using RF heating

Methodology Applied

Scientific EffectRF heating: Dielectric Heating

Implementation Method 2

supplying RF power, via the RF transmission line, to the tubular conductor so that the tubular conductor serves as an RF antenna to heat the hydrocarbon resources

Methodology Applied

Scientific EffectElectromagnetic induction: Electromagnetic Induction

Data Source

PatentUS9581002B2Method of heating a hydrocarbon resource including slidably positioning an RF transmission line and related apparatus

Publication Date: 2017.02.28 HARRIS CORP

AI summary

A method for heating hydrocarbon resources in a subterranean formation may include positioning a tubular conductor within a wellbore in the subterranean formation and slidably positioning a radio frequency (RF) transmission line within the tubular conductor so that a distal end of the transmission line is electrically coupled to the tubular conductor. The method may also include supplying RF power, via the RF transmission line, to the tubular conductor so that the tubular conductor serves as an RF antenna to heat the hydrocarbon resources in the subterranean formation.