Title

The Effects of In-Situ Condition Curing on Oil Well Cements Properties of CO2 Sequestration Injection Wells

Presenter Information

Chidiebere Onukogu

Department

Geosciences and Geological and Petroleum Engineering

Major

Petroleum Engineering

Research Advisor

Nygaard, Runar

Advisor's Department

Geosciences and Geological and Petroleum Engineering

Funding Source

Opportunities for Undergraduate Experience Program (OURE)

Abstract

CO2 sequestration is a method to counteract the large amounts of CO2 being produced into the atmosphere. It works by pumping CO2 in super critical phase into the subsurface where it is stored in the same manner as hydrocarbons. Missouri has been working on CO2 sequestration projects to help reduce the state's carbon emissions from power plants. CO2 is injected through wellbores into the holding formation which are cased and cemented wellbores. Cement is one of the primary barriers of leakage and this integrity is based off the cement’s physical properties. Many of the cement properties are known at atmospheric conditions, but the cement properties will vary once the cement is cured at in-situ conditions. Curing is one of the most important steps in cement construction, because proper curing greatly increases cement strength and durability. Cement hardens as a result of hydration which is the chemical reaction between cement and water. Cement requires a moist, controlled environment to gain strength and harden fully. The cement paste hardens over time, initially setting and becoming rigid though very weak and gaining in strength in the weeks following. In around 4 weeks, typically over 90% of the final strength is reached, though strengthening may continue for decades. Properly curing concrete leads to increased strength and lower permeability and avoids cracking where the surface dries out prematurely. A set of the same cement was prepared to conduct the lab experiment. The samples will be cured under simulated wellbore curing conditions for 7 days at 180 degrees Fahrenheit and 1500 psi initially. A measurement of each sample’s physical properties was then conducted. These measurements include compressive strength, thermal conductivity, thermal expansion, Young’s modulus, Poisson’s ratio, permeability, volume changes (shrinkage or expansion), Rheology, and Settling. Then integrity will be checked using finite element analysis. In conclusion, the physical properties of cement at atmospheric conditions differ from the physical properties of cement at in-situ conditions. These in-suit conditions must be known when considering the integrity of your cement for CO2 sequestration. Otherwise, the integrity of the injection well cannot be predicted.

Biography

Chidiebere Onukogu is a senior studying Petroleum Engineering with a minor in Geology at Missouri S&T. He is the treasurer of the Pi Epsilon Tau Petroleum Honor Society, the event coordinator of the Society of Petroleum Engineers, and a member of the American Association of Drilling Engineers. After graduation, Chidiebere plans to further his education by pursuing a Masters’ in Petroleum Engineering and eventually his PhD. His interests includes sports, working out, researching, and spending time with his family.

Research Category

Engineering

Presentation Type

Poster Presentation

Document Type

Poster

Location

Upper Atrium/Hall

Presentation Date

16 Apr 2014, 1:00 pm - 3:00 pm

This document is currently not available here.

Share

COinS
 
Apr 16th, 1:00 PM Apr 16th, 3:00 PM

The Effects of In-Situ Condition Curing on Oil Well Cements Properties of CO2 Sequestration Injection Wells

Upper Atrium/Hall

CO2 sequestration is a method to counteract the large amounts of CO2 being produced into the atmosphere. It works by pumping CO2 in super critical phase into the subsurface where it is stored in the same manner as hydrocarbons. Missouri has been working on CO2 sequestration projects to help reduce the state's carbon emissions from power plants. CO2 is injected through wellbores into the holding formation which are cased and cemented wellbores. Cement is one of the primary barriers of leakage and this integrity is based off the cement’s physical properties. Many of the cement properties are known at atmospheric conditions, but the cement properties will vary once the cement is cured at in-situ conditions. Curing is one of the most important steps in cement construction, because proper curing greatly increases cement strength and durability. Cement hardens as a result of hydration which is the chemical reaction between cement and water. Cement requires a moist, controlled environment to gain strength and harden fully. The cement paste hardens over time, initially setting and becoming rigid though very weak and gaining in strength in the weeks following. In around 4 weeks, typically over 90% of the final strength is reached, though strengthening may continue for decades. Properly curing concrete leads to increased strength and lower permeability and avoids cracking where the surface dries out prematurely. A set of the same cement was prepared to conduct the lab experiment. The samples will be cured under simulated wellbore curing conditions for 7 days at 180 degrees Fahrenheit and 1500 psi initially. A measurement of each sample’s physical properties was then conducted. These measurements include compressive strength, thermal conductivity, thermal expansion, Young’s modulus, Poisson’s ratio, permeability, volume changes (shrinkage or expansion), Rheology, and Settling. Then integrity will be checked using finite element analysis. In conclusion, the physical properties of cement at atmospheric conditions differ from the physical properties of cement at in-situ conditions. These in-suit conditions must be known when considering the integrity of your cement for CO2 sequestration. Otherwise, the integrity of the injection well cannot be predicted.