Next Article in Journal
Removal of Cr(VI) from Water Using a New Reactive Material: Magnesium Oxide Supported Nanoscale Zero-Valent Iron
Next Article in Special Issue
Fatigue and Fracture Behavior of a Cold-Drawn Commercially Pure Aluminum Wire
Previous Article in Journal
Nano-Crystalline Li1.2Mn0.6Ni0.2O2 Prepared via Amorphous Complex Precursor and Its Electrochemical Performances as Cathode Material for Lithium-Ion Batteries
Previous Article in Special Issue
Healing of Fatigue Crack in 1045 Steel by Using Eddy Current Treatment
Article Menu
Issue 8 (August) cover image

Export Article

Open AccessArticle
Materials 2016, 9(8), 663; doi:10.3390/ma9080663

Experimental Investigation of Mechanical Properties of Black Shales after CO2-Water-Rock Interaction

1
Wuhan University, Wuhan 430072, China
2
Key Laboratory of Hubei Province for Water Jet Theory & New Technology, Wuhan 430072, China
3
Deep Earth Energy Laboratory, Department of Civil Engineering, Monash University, Melbourne 3800, Australia
*
Author to whom correspondence should be addressed.
Academic Editor: Yoshiharu Mutoh
Received: 26 July 2016 / Revised: 2 August 2016 / Accepted: 3 August 2016 / Published: 6 August 2016
(This article belongs to the Special Issue Fracture and Fatigue Mechanics of Materials)
View Full-Text   |   Download PDF [8586 KB, uploaded 6 August 2016]   |  

Abstract

The effects of CO2-water-rock interactions on the mechanical properties of shale are essential for estimating the possibility of sequestrating CO2 in shale reservoirs. In this study, uniaxial compressive strength (UCS) tests together with an acoustic emission (AE) system and SEM and EDS analysis were performed to investigate the mechanical properties and microstructural changes of black shales with different saturation times (10 days, 20 days and 30 days) in water dissoluted with gaseous/super-critical CO2. According to the experimental results, the values of UCS, Young’s modulus and brittleness index decrease gradually with increasing saturation time in water with gaseous/super-critical CO2. Compared to samples without saturation, 30-day saturation causes reductions of 56.43% in UCS and 54.21% in Young’s modulus for gaseous saturated samples, and 66.05% in UCS and 56.32% in Young’s modulus for super-critical saturated samples, respectively. The brittleness index also decreases drastically from 84.3% for samples without saturation to 50.9% for samples saturated in water with gaseous CO2, to 47.9% for samples saturated in water with super-critical carbon dioxide (SC-CO2). SC-CO2 causes a greater reduction of shale’s mechanical properties. The crack propagation results obtained from the AE system show that longer saturation time produces higher peak cumulative AE energy. SEM images show that many pores occur when shale samples are saturated in water with gaseous/super-critical CO2. The EDS results show that CO2-water-rock interactions increase the percentages of C and Fe and decrease the percentages of Al and K on the surface of saturated samples when compared to samples without saturation. View Full-Text
Keywords: shale; CO2-water-rock interaction; mechanical properties; crack propagation; microstructure shale; CO2-water-rock interaction; mechanical properties; crack propagation; microstructure
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

Scifeed alert for new publications

Never miss any articles matching your research from any publisher
  • Get alerts for new papers matching your research
  • Find out the new papers from selected authors
  • Updated daily for 49'000+ journals and 6000+ publishers
  • Define your Scifeed now

SciFeed Share & Cite This Article

MDPI and ACS Style

Lyu, Q.; Ranjith, P.G.; Long, X.; Ji, B. Experimental Investigation of Mechanical Properties of Black Shales after CO2-Water-Rock Interaction. Materials 2016, 9, 663.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Materials EISSN 1996-1944 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top