Changes in the pore characteristics of shale during comminution

The correct understanding of shale pore characteristics is the foundation of shale gas exploration and development. Comminution is an essential sample pretreatment in many measurements of shale pore characteristics, but little is known about the influence of comminution on shale pore characteristics. This study utilizes low-pressure nitrogen adsorption and helium porosity measurements to investigate the evolution of shale pore characteristics during comminution. The results show that reducing the proportion of inaccessible pores and improving the gas diffusion efficiency are the main effects of comminution on the shale pore characteristics, resulting in an increase in measured porosity. The recommended analytical shale particle size for low-pressure nitrogen adsorption and helium porosity measurements is below 80 and 20 mesh, respectively. The proportion of inaccessible pores in shale investigated in this study ranges from 13.11 to 45.89% and shows a negative correlation with thermal maturity and a positive correlation with clay content. This suggests an improvement of organic pore accessibility during thermal evolution and a high content of inaccessible pores in clay minerals.

[1]  Yidong Cai,et al.  Pore Structure and Compressibility of Coal Matrix with Elevated Temperatures by Mercury Intrusion Porosimetry , 2015 .

[2]  Jiang Yang,et al.  Advances of Nanotechnologies in Oil and Gas Industries , 2015 .

[3]  Hao Xu,et al.  A precise measurement method for shale porosity with low-field nuclear magnetic resonance: A case study of the Carboniferous-Permian strata in the Linxing area, eastern Ordos Basin, China , 2015 .

[4]  A. Schimmelmann,et al.  The effect of analytical particle size on gas adsorption porosimetry of shale , 2015 .

[5]  Guy De Weireld,et al.  First international inter-laboratory comparison of high-pressure CH4, CO2 and C2H6 sorption isotherms on carbonaceous shales , 2014 .

[6]  X. Xiao,et al.  Evolution of nanoporosity in organic-rich shales during thermal maturation , 2014 .

[7]  A. Derkowski,et al.  Total porosity measurement in gas shales by the water immersion porosimetry (WIP) method , 2014 .

[8]  U. Kuila,et al.  Application of nitrogen gas-adsorption technique for characterization of pore structure of mudrocks , 2013 .

[9]  A. Schimmelmann,et al.  Porosity of Devonian and Mississippian New Albany Shale across a maturation gradient: Insights from organic petrology, gas adsorption, and mercury intrusion , 2013 .

[10]  Milind Deo,et al.  Characterization of oil shale pore structure before and after pyrolysis by using X-ray micro CT , 2013 .

[11]  Richard E. Lewis,et al.  NMR T2 Distributions in the Eagle Ford Shale: Reflections on Pore Size , 2013 .

[12]  Lilin He,et al.  A USANS/SANS Study of the Accessibility of Pores in the Barnett Shale to Methane and Water , 2013 .

[13]  Celso Peres Fernandes,et al.  Characterization of pore systems in seal rocks using Nitrogen Gas Adsorption combined with Mercury Injection Capillary Pressure techniques , 2013 .

[14]  Christopher R. Clarkson,et al.  Pore structure characterization of North American shale gas reservoirs using USANS/SANS, gas adsorption, and mercury intrusion , 2013 .

[15]  Paul C. Hackley,et al.  The nature of porosity in organic-rich mudstones of the Upper Jurassic Kimmeridge Clay Formation, North Sea, offshore United Kingdom , 2012 .

[16]  Maria Mastalerz,et al.  Porosity of Coal and Shale: Insights from Gas Adsorption and SANS/USANS Techniques , 2012 .

[17]  R. Marc Bustin,et al.  Characterization of gas shale pore systems by porosimetry, pycnometry, surface area, and field emission scanning electron microscopy/transmission electron microscopy image analyses: Examples from the Barnett, Woodford, Haynesville, Marcellus, and Doig units , 2012 .

[18]  Stephen C. Ruppel,et al.  Spectrum of pore types and networks in mudrocks and a descriptive classification for matrix-related mudrock pores , 2012 .

[19]  R. Loucks,et al.  Morphology, Genesis, and Distribution of Nanometer-Scale Pores in Siliceous Mudstones of the Mississippian Barnett Shale , 2009 .

[20]  R. M. Bustin,et al.  Measurements of gas permeability and diffusivity of tight reservoir rocks: different approaches and their applications , 2009 .

[21]  Hong-Cai Zhou,et al.  Selective gas adsorption and separation in metal-organic frameworks. , 2009, Chemical Society reviews.

[22]  R. L. Robinson,et al.  Experimental Uncertainties in Volumetric Methods for Measuring Equilibrium Adsorption , 2009 .

[23]  J. Curtis.  Fractured shale-gas systems , 2002 .

[24]  P. Harting,et al.  Highest Pressure Adsorption Equilibria Data: Measurement with Magnetic Suspension Balance and Analysis with a New Adsorbent/Adsorbate-Volume , 2002 .

[25]  Shivaji Sircar,et al.  Measurement of gibbsian surface excess , 2001 .

[26]  L. Davis,et al.  Petrophysical Measurements on Shales Using NMR , 2000 .

[27]  M. Hodson.  Micropore surface area variation with grain size in unweathered alkali feldspars: implications for surface roughness and dissolution studies , 1998 .

[28]  D. L. Luffel,et al.  New Core Analysis Methods for Measuring Reservoir Rock Properties of Devonian Shale , 1992 .

[29]  K. Sing.  Reporting physisorption data for gas/solid systems with special reference to the determination of surface area and porosity (Recommendations 1984) , 1985 .

[30]  K. Kawazoe,et al.  METHOD FOR THE CALCULATION OF EFFECTIVE PORE SIZE DISTRIBUTION IN MOLECULAR SIEVE CARBON , 1983 .

[31]  E. Barrett,et al.  (CONTRIBUTION FROM THE MULTIPLE FELLOWSHIP OF BAUGH AND SONS COMPANY, MELLOX INSTITUTE) The Determination of Pore Volume and Area Distributions in Porous Substances. I. Computations from Nitrogen Isotherms , 1951 .