C5 Cement Carbonation Curing for Strength and Lower Emissions

Solution Overview

Problem

The cement industry is energy-intensive and a significant contributor to global CO2 emissions, with existing alternatives either lacking in mechanical strength or stability, or requiring high energy processes.

Innovation Solution

Development of C5 cements using pseudowollastonite as a calcium silicate precursor, cured at intermediate temperatures and high CO2 concentrations, forming crystalline calcium silicate hydrates that enhance strength and durability, utilizing industrial waste materials as feedstocks.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If Portland cement is produced using conventional high-temperature sintering processes, then the cement achieves required strength and durability, but energy consumption and CO2 emissions increase significantly

Engineering Contradiction:

Improvecement strengthVSAvoidenergy consumption

Core Design Contradiction:

StrengthVSUse of energy by moving object

Solution Approach 1:

The invention changes the curing parameters from high-temperature sintering (1450°C) to intermediate temperature carbonation curing (50-250°C). This parameter change allows the formation of crystalline calcium silicate hydrate phases through carbonation reactions rather than high-temperature sintering, thereby reducing energy consumption while maintaining cement strength and durability

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention converts CO2, which is normally a harmful emission, into a beneficial curing agent. By introducing CO2 during the curing process, the material undergoes carbonation reactions that form strong crystalline phases, thus transforming the harmful greenhouse gas into a useful resource that enhances cement performance while sequestering carbon

Inventive Principle:

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

2Strength

If Portland cement is produced using conventional high-temperature sintering processes, then the cement achieves required strength and durability, but CO2 emissions increase significantly

Engineering Contradiction:

Improvecement strengthVSAvoidCO2 emissions

Core Design Contradiction:

StrengthVSObject-generated harmful factors

Solution Approach 1:

The invention converts CO2, which is normally a harmful emission, into a beneficial curing agent. By introducing CO2 during the curing process, the material undergoes carbonation reactions that form strong crystalline phases, thus transforming the harmful greenhouse gas into a useful resource that enhances cement performance while sequestering carbon

Inventive Principle:

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

Solution Approach 2:

The invention changes the production approach from high-temperature sintering that releases CO2 to intermediate temperature carbonation curing that consumes CO2. This parameter change in the curing process transforms the harmful emission into a beneficial reactant, reducing net CO2 emissions while maintaining cement strength

Inventive Principle:

Principle #35Parameter changes

3Use of energy by moving object

If alternative cementitious materials are used to reduce energy consumption and CO2 emissions, then environmental performance improves, but mechanical strength and chemical stability deteriorate

Engineering Contradiction:

Improveenergy consumptionVSAvoidmechanical strength

Core Design Contradiction:

Use of energy by moving objectVSStrength

Solution Approach 1:

The invention changes the curing parameters from ambient or low-energy conditions to controlled intermediate temperature (50-250°C) and elevated CO2 pressure conditions. This parameter optimization enables the formation of dense crystalline calcium silicate hydrate phases that provide both high mechanical strength and chemical stability, overcoming the typical trade-off between low-energy processing and material performance

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention creates a composite microstructure consisting of crystalline calcium silicate hydrate phases formed through carbonation reactions. This crystalline composite structure, with plate-like morphology, provides enhanced mechanical strength and chemical stability compared to amorphous alternatives, while still being produced through lower energy processes

Inventive Principle:

Principle #40Composite materials

4Use of energy by moving object

If alternative cementitious materials are used to reduce energy consumption and CO2 emissions, then environmental performance improves, but chemical stability deteriorates

Engineering Contradiction:

Improveenergy consumptionVSAvoidchemical stability

Core Design Contradiction:

Use of energy by moving objectVSStability of the object's composition

Solution Approach 1:

The invention changes the curing parameters from ambient or low-energy conditions to controlled intermediate temperature (50-250°C) and elevated CO2 pressure conditions. This parameter optimization enables the formation of dense crystalline calcium silicate hydrate phases that provide both high mechanical strength and chemical stability, overcoming the typical trade-off between low-energy processing and material performance

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention converts CO2, which is normally a harmful emission, into a beneficial curing agent. By introducing CO2 during the curing process, the material undergoes carbonation reactions that form strong crystalline phases, thus transforming the harmful greenhouse gas into a useful resource that enhances cement performance while sequestering carbon

Inventive Principle:

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

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

C5 cements exhibit higher strength, lower permeability, and chemical stability, reducing energy consumption and CO2 emissions while sequestering carbon, suitable for precast concrete applications.

Implementation Method 1

contacting a cementitious material comprising a calcium silicate precursor with water and carbon dioxide under conditions effective to form crystalline calcium silicate hydrates within the cementitious material

Methodology Applied

Scientific EffectCarbonation:

Implementation Method 2

the calcium silicate precursor can comprise a discrete calcium silicate phase that exhibits congruent dissolution (also referred to as stoichiometric dissolution) in water, such dissolution of the calcium silicate precursor releases Ca and Si in approximately equimolar amounts during dissolution

Methodology Applied

Scientific EffectDissolution:

Data Source

PatentUS20250236559A1Cementitious materials and methods of making and using thereof

Publication Date: 2025.07.24 UNIV OF VIRGINIA PATENT FOUND

AI summary

Disclosed are cementitious materials as well as methods of forming cured cementitious materials.