Fiber Optic CO2 Leak Sensing for Carbon Storage Wells

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current methods for detecting CO2 leakage in carbon storage wells are not location-specific and can disrupt operations, risking equipment damage, while existing fiber optic approaches lack direct measurement capabilities.

Innovation Solution

An optical fiber system with integrated leak sensors and detection units is deployed within the well for real-time, direct detection of CO2 leakage, utilizing Fiber Bragg Gratings and Slotted Holey Fibers for spectroscopy and optical time-domain reflectometry, providing simultaneous measurements of CO2 concentration and other parameters.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If current industry methods are used to detect gas leakage, then leakage detection is achieved, but the detection is not location-specific and operations are disrupted with risk of equipment damage

Engineering Contradiction:

Improvelocation-specific detection precisionVSAvoidoperational disruption and equipment safety

Core Design Contradiction:

Measurement precisionVSEase of operation

Solution Approach 1:

The patent replaces mechanical/disruptive detection methods with optical fiber-based sensing. The optical fiber system uses light propagation and optical time-domain reflectometry (OTDR) to detect CO2 leakage locations without mechanical contact or operational disruption, achieving both location-specific precision and operational continuity.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The optical fiber acts as an intermediary sensor that can be positioned within the well to detect CO2 leakage at specific locations. This intermediary approach allows remote, non-intrusive measurement that provides location-specific data without disrupting well operations or risking equipment damage.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Measurement precision

If existing fiber optic approaches are used, then some detection capability is provided, but direct measurement of CO2 concentration is not achieved

Engineering Contradiction:

Improvedirect CO2 concentration measurementVSAvoidsensor system complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent employs slotted hollow core optical fibers that function as porous-like structures allowing CO2 gas to interact with the optical mode. The slots in the hollow core enable gas permeation and direct interaction between the analyte and evanescent field, achieving direct concentration measurement while maintaining relatively simple fiber optic technology.

Inventive Principle:

Principle #31Porous materials

Solution Approach 2:

The system detects CO2 concentration by measuring changes in optical parameters (attenuation, phase, or wavelength) caused by CO2 interaction with the optical fiber. This parameter-based detection approach enables direct concentration measurement using standard optical fiber technology without requiring complex additional sensors.

Inventive Principle:

Principle #35Parameter changes

3Reliability

If optical fiber is positioned in the well for detection, then location-specific real-time detection is achieved, but the system must handle harsh subsurface conditions

Engineering Contradiction:

Improvereal-time detection reliabilityVSAvoidsubsurface environmental conditions

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The hollow core optical fiber creates an inert optical environment where light propagates through air or vacuum rather than through the harsh subsurface medium. This isolates the sensing mechanism from corrosive chemicals, high temperatures, and pressure, enabling reliable real-time detection in harsh subsurface conditions.

Inventive Principle:

Principle #39Inert atmosphere (Inert environment)

Solution Approach 2:

The optical fiber uses flexible polymer coatings and protective jackets that can withstand subsurface environmental conditions. These protective layers allow the fiber to be positioned in harsh environments while protecting the delicate optical core from chemical and mechanical damage, ensuring reliable operation.

Inventive Principle:

Principle #30Flexible shells and thin films

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

Enables real-time, location-specific detection of CO2 leakage, identifying small leaks and potential blow-outs, protecting underground water sources and enhancing operational safety.

Implementation Method 1

a first section of the optical fiber positioned in the monitoring well at a first depth in the monitoring well, wherein the first section of the optical fiber has a first center wavelength that corresponds to an absorption line of carbon dioxide

Methodology Applied

Scientific EffectAbsorption Spectroscopy: Absorption Spectroscopy

Implementation Method 2

detection of optical events in the optical fiber using optical time-domain reflectometry

Methodology Applied

Scientific EffectOptical Time-Domain Reflectometry:

Implementation Method 3

Methodology Applied

Scientific EffectBragg Diffraction: Bragg Diffraction

Data Source

PatentUS12487145B2Autonomous fiber optic system for direct detection of CO<sub>2 </sub>leakage in carbon storage wells

Publication Date: 2025.12.02 LAWRENCE LIVERMORE NAT SECURITY LLC

AI summary

Direct detection of carbon dioxide leakage in a carbon storage well is obtained using an optical fiber adapted to be positioned in the carbon storage well, a detection unit operatively connected to the optical fiber, and a leak sensor section incorporated in the optical fiber.