In Situ CO2 Removal via Calcite Precipitation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Natural gas extraction contributes to increased atmospheric carbon dioxide concentrations, and the presence of CO2 in natural gas reduces its heat value, necessitating effective in situ CO2 removal from gas wells to mitigate climate change and enhance energy efficiency.

Innovation Solution

Introducing a high-pH, calcium-rich treatment fluid into subterranean formations containing natural gas and CO2, where calcium reacts with CO2 to form calcite, reducing CO2 concentrations, using slaked lime to maintain a high pH and calcium chloride to fortify calcium levels as needed, with reactive transport modeling to optimize conditions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional geology carbon sequestration is used to store CO2 subsurface, then CO2 can be trapped in underground reservoirs, but the process is extremely slow taking thousands of years to fully capture CO2

Engineering Contradiction:

Improvelong-term retention of CO2VSAvoidrate of CO2 capture

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The patent changes the chemical parameters of the injection fluid by raising pH to 11 or greater using slaked lime and increasing calcium concentration to 1.5 M or greater using calcium chloride. These parameter changes accelerate the mineralization reaction rate, transforming CO2 into calcite much faster than natural processes, thereby resolving the contradiction between reliable long-term retention and fast capture rate.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent introduces slaked lime as an intermediary substance that mediates between CO2 and calcium sources. The slaked lime raises the pH to create optimal conditions for rapid calcite formation, acting as a catalyst that speeds up the sequestration process while maintaining long-term storage reliability.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Productivity

If CO2 is co-produced with extracted natural gas, then natural gas can be extracted from reservoirs, but atmospheric CO2 concentrations increase contributing to climate change

Engineering Contradiction:

Improvenatural gas extractionVSAvoidCO2 emissions

Core Design Contradiction:

ProductivityVSObject-generated harmful factors

Solution Approach 1:

The patent converts the harmful CO2 emissions into beneficial calcite mineral storage. By injecting treatment fluid that reacts with CO2 to form insoluble calcite, the method transforms the harmful greenhouse gas into a stable, long-term stored mineral, eliminating emissions while maintaining natural gas production.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The patent applies preliminary action by injecting the treatment fluid into the formation before CO2 reaches the surface. This proactive approach prevents CO2 from being co-produced with natural gas by removing it in situ at the source, thereby preventing harm before it occurs.

Inventive Principle:

Principle #10Preliminary action

3Productivity

If CO2 is present in natural gas, then natural gas can be extracted, but the heat value of natural gas is reduced lowering energy output

Engineering Contradiction:

Improvenatural gas productionVSAvoidenergy output

Core Design Contradiction:

ProductivityVSLoss of energy

Solution Approach 1:

The patent performs preliminary removal of CO2 from natural gas at the source by injecting treatment fluid into the formation. This preliminary action prevents CO2 from mixing with the produced gas, thereby maintaining the heat value and energy output of the natural gas without requiring post-extraction separation processes.

Inventive Principle:

Principle #10Preliminary action

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

Effectively reduces CO2 concentrations in natural gas before production, enhancing energy output and long-term carbon sequestration by converting CO2 into insoluble calcite, with ongoing mineralization reactions continuing after treatment fluid cessation.

Implementation Method 1

allowing the calcium in the treatment fluid to react with the carbon dioxide within the subterranean formation to form calcite

Methodology Applied

Scientific EffectChemical reaction: Chemical Bonding

Implementation Method 2

creating treatment fluid by introducing an amount of slaked lime to the origin fluid to change a pH of the resulting treatment fluid to about 11 or greater

Methodology Applied

Scientific EffectpH adjustment:

Implementation Method 3

introducing an amount of calcium chloride to the calcium-lean aqueous fluid to obtain an aqueous fluid having a calcium concentration of about 1.5 M or greater

Methodology Applied

Scientific EffectDissolution: Solvation

Data Source

PatentUS12129749B1Methods for removing carbon dioxide from natural gas

Publication Date: 2024.10.29 SAUDI ARABIAN OIL CO

AI summary

Methods of the present disclosure may include obtaining an origin fluid having a calcium concentration of about 1.5 M or greater. A treatment fluid may be created by introducing an amount of slaked lime to the origin fluid to change a pH of the resulting treatment fluid to about 11 or greater. The treatment fluid may be introduced into a subterranean formation containing a formation gas comprising natural gas and carbon dioxide. The calcium in the treatment fluid may be allowed to react with the carbon dioxide within the subterranean formation to form calcite. The treated formation gas may be removed from the subterranean formation after the formation of calcite, wherein the concentration of carbon dioxide in the treated formation gas is lower than the formation gas before it was contacted with the treatment fluid.