Calcium Aluminate Cement Workability via Mineral Phase Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing calcium aluminate cements face challenges in controlling workability and hardening kinetics, especially at high temperatures, and are prone to accelerated setting due to interactions with Portland cements, leading to issues in applications like oil well drilling where precise temperature control is crucial.
Innovation Solution
A calcium aluminate cement with a high mass fraction of crystallized mineralogical phases CA2 and C2AS, which provides naturally long workability and controlled hydration kinetics without the need for retarders, and minimizes interactions with Portland cements, ensuring stable performance even in high-temperature conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If calcium aluminate cement is used to provide high resistance to acid corrosion and high temperatures, then chemical and mechanical resistance is improved, but workability control and hardening kinetics become difficult especially at elevated temperatures
Solution Approach 1:
The patent modifies the mineralogical composition parameters of calcium aluminate cement by incorporating specific phases (CA2, C12A7, and C4A3S) in controlled proportions. This changes the chemical parameters of the cement to achieve both high temperature resistance and improved workability control, resolving the contradiction between reliability and ease of operation
Solution Approach 2:
The patent creates a composite cement system combining multiple mineralogical phases (CA2, C12A7, C4A3S) with complementary properties. CA2 provides temperature resistance, C12A7 extends workability, and C4A3S controls hardening kinetics, achieving both high reliability and ease of operation through material composition
2Productivity
If temperature is increased to accelerate hardening kinetics, then setting speed is improved, but workability is reduced due to faster thickening and hydraulic setting
Solution Approach 1:
The patent changes the chemical composition parameters by incorporating C12A7 and C4A3S phases that modify the hydration reaction characteristics. These compositional changes allow the cement to maintain workability at elevated temperatures while still achieving accelerated hardening kinetics, resolving the contradiction between productivity and duration of action
3Duration of action of moving object
If retarders are added to extend workability at high temperatures, then workability duration is improved, but mechanical resistance of the hardened material is reduced
Solution Approach 1:
The patent enables the cement to self-regulate its setting and hardening processes through its inherent mineralogical composition (CA2, C12A7, C4A3S phases). The C12A7 phase naturally extends workability at high temperatures without requiring external retarders, while the C4A3S phase ensures proper hardening kinetics, achieving both extended workability duration and maintained mechanical resistance through the material's own properties
Solution Approach 2:
The patent modifies the chemical composition by incorporating specific mineralogical phases that inherently control setting and hardening behavior. This compositional parameter change eliminates the need for retarders while maintaining both extended workability and high mechanical resistance, resolving the contradiction between duration of action and strength
4Productivity
If calcium aluminate cement interacts with Portland cement, then setting acceleration occurs, but premature hardening and contamination issues arise
Solution Approach 1:
The patent modifies the chemical composition parameters by incorporating C4A3S phase which has low solubility and reduced interaction with Portland cement components. This compositional change reduces unwanted interactions and contamination while maintaining controlled setting kinetics, resolving the contradiction between productivity and reliability
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
The calcium aluminate cement exhibits extended workability and controlled hardening kinetics, maintaining mechanical and chemical resistance similar to traditional calcium aluminate cements, while allowing for precise temperature-induced setting, reducing the risk of premature hardening and contamination effects.
Implementation Method 1
a cement is a mineral powder designed to be mixed with water in order to form a cementitious composition that hardens
Implementation Method 2
the hydraulic setting being an accelerated exothermic phase of the hydration reaction of the cement by the water
Implementation Method 3
a first crystallised mineralogical phase of calcium dialuminate CA2 comprising one calcium oxide CaO for two aluminium oxides Al2O3 and/or a second crystallised mineralogical phase of dicalcium alumina silicate C2AS
Data Source
AI summary
Disclosed is a calcium aluminate cement, including a calcium aluminate with a first crystallised mineralogical phase of calcium dialuminate CA2 including one calcium oxide CaO for two aluminium oxides Al2O3 and/or a second crystallised mineralogical phase of dicalcium alumina silicate C2AS including two calcium oxides CaO for one aluminium oxide Al2O3 and one silicon dioxide SiO2. The mass fraction of all of the first and second mineralogical phases in the calcium aluminate is greater than or equal to 80%.