Barite precipitation in porous media: Impact of pore structure and surface charge on ionic diffusion

ABSTRACTKnowledge of the evolution of the permeability of cement throughout the course of hydration provides a suitable means to evaluate the evolution of the pore structure. The main difficulty is to measure permeability without disturbing the tenuous structure of the material at the beginning of the hydration. We have developed a differential permeability technique in which the applied flow is sufficiently weak that the structure of the medium is not disturbed. As an example of application of this technique we present measurement of the evolution of the critical permeability during a sol-gel transition.

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Flax Biomass Conversion via Controlled Oxidation: Facile Tuning of Physicochemical Properties

Bioengineering ◽

10.3390/bioengineering7020038 ◽

2020 ◽

Vol 7 (2) ◽

pp. 38

Author(s):

Leila Dehabadi ◽

Abdalla H. Karoyo ◽

Majid Soleimani ◽

Wahab O. Alabi ◽

Carey J. Simonson ◽

...

Keyword(s):

Chemical Modification ◽

Pore Structure ◽

Surface Charge ◽

Chemical Treatment ◽

Textural Properties ◽

Adsorption Properties ◽

Biomass Composition ◽

Adsorption Sites ◽

Modified Forms

The role of chemical modification of pristine linen fiber (LF) on its physicochemical and adsorption properties is reported in this contribution. The surface and textural properties of the pristine LF and its peroxyacetic acid- (PAF) and chlorite-treated (CF) fiber forms were characterized by several complementary methods: spectroscopy (SEM, TEM, FT-IR, and XPS), thermal analysis (DSC and TGA), gas/water adsorption isotherms, and zeta potential (ξ). The results obtained reveal that the surface charge and textural properties (surface area and pore structure) of the LF material was modified upon chemical treatment, as indicated by changes in the biomass composition, morphology, ξ-values, and water/dye uptake properties of the fiber samples. Particularly, the pristine LF sample displays preferential removal efficiency (ER) of methylene blue (MB) dye with ER ~3-fold greater (ER~62%) as compared to the modified materials (CF or PAF; ER~21%), due to the role of surface charge of pectins and lignins present in pristine LF. At higher MB concentration, the relative ER values for LF (~19%) relative to CF or PAF (~16%) reveal the greater role of micropore adsorption sites due to the contributing effect of the textural porosity observed for the modified flax biomass at these conditions. Similar trends occur for the adsorption of water in the liquid vs. vapour phases. The chemical treatment of LF alters the polarity/charge of the surface functional groups, and pore structure properties of the chemically treated fibers, according to the variable hydration properties. The surface and textural properties of LF are altered upon chemical modification, according to the variable adsorption properties with liquid water (l) vs. water vapor (g) due to the role of surface- vs. pore-sites. This study contributes to an understanding of the structure-adsorption properties for pristine and oxidized flax fiber biomass. The chemical conversion of such biomass yields biomaterials with tunable surface and textural properties, as evidenced by the unique adsorption properties observed for pristine LF and its modified forms (CF and PAF). This study addresses knowledge gaps in the field by contributing insight on the relationship between structure and adsorption properties of such LF biomass in its pristine and chemically modified forms.

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Network modelling of pore structure and transport properties of porous media

Chemical Engineering Science ◽

10.1016/0009-2509(93)80333-l ◽

1993 ◽

Vol 48 (5) ◽

pp. 951-972 ◽

Cited By ~ 93

Author(s):

Marios A. Ioannidis ◽

Ioannis Chatzis

Keyword(s):

Porous Media ◽

Pore Structure ◽

Transport Properties ◽

Network Modelling

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Changes in multi-phase flow properties of carbonate porous media during CO2 injection

The APPEA Journal ◽

10.1071/aj19061 ◽

2020 ◽

Vol 60 (2) ◽

pp. 672

Author(s):

Mojtaba Seyyedi ◽

Ausama Giwelli ◽

Cameron White ◽

Lionel Esteban ◽

Michael Verrall ◽

...

Keyword(s):

Porous Media ◽

Pore Structure ◽

Relative Permeability ◽

Carbonate Rock ◽

Trapping Potential ◽

Co2 Injection ◽

Phase Flow ◽

Residual Trapping ◽

Multi Phase Flow ◽

Multi Phase

Impacts of fluid–rock geochemical reactions occurring during CO2 injection into underground formations, including CO2 geosequestration, on porosity and single-phase permeability are well documented. However, their impacts on pore structure and multi-phase flow behaviour of porous media and, therefore, on CO2 injectivity and residual trapping potential, are yet unknown. We found that CO2-saturated brine–rock interactions in a carbonate rock led to a decrease in the sweep efficiency of the non-wetting phase (gas) during primary drainage. Furthermore, they led to an increase in the relative permeability of the non-wetting phase, a decrease in the relative permeability of the wetting phase (brine) and a reduction in the residual trapping potential of the non-wetting phase. The impacts of reactions on pore structure shifted the relative permeability cross-point towards more water-wet condition. Finally, calcite dissolution caused a reduction in capillary pressure of the used carbonate rock. For CO2 underground injection applications, such changes in relative permeabilities, residual trapping potential of the non-wetting phase (CO2) and capillary pressure would reduce the CO2 storage capacity and increase the risk of CO2 leakage.

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Electrical conductivity, spontaneous potential and ionic diffusion in porous media

Geological Society London Special Publications ◽

10.1144/gsl.sp.1997.122.01.15 ◽

1997 ◽

Vol 122 (1) ◽

pp. 253-275 ◽

Cited By ~ 7

Author(s):

A. Revil ◽

P. A. Pezard ◽

M. Darot

Keyword(s):

Electrical Conductivity ◽

Porous Media ◽

Ionic Diffusion ◽

Spontaneous Potential ◽

Diffusion In Porous Media

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Co-transport and retention of zwitterionic ciprofloxacin with nano-biochar in saturated porous media: Impact of oxidized aging

The Science of The Total Environment ◽

10.1016/j.scitotenv.2021.146417 ◽

2021 ◽

Vol 779 ◽

pp. 146417

Author(s):

Shishu Zhu ◽

Weigao Zhao ◽

Pan Wang ◽

Lingan Zhao ◽

Chao Jin ◽

...

Keyword(s):

Porous Media ◽

Saturated Porous Media ◽

Media Impact

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RECENT ADVANCES ON FRACTAL MODELING OF PERMEABILITY FOR FIBROUS POROUS MEDIA

Fractals ◽

10.1142/s0218348x1540006x ◽

2015 ◽

Vol 23 (01) ◽

pp. 1540006 ◽

Cited By ~ 77

Author(s):

JIANCHAO CAI ◽

LIANG LUO ◽

RAN YE ◽

XIANGFENG ZENG ◽

XIANGYUN HU

Keyword(s):

Porous Media ◽

Pore Structure ◽

Fractal Geometry ◽

Influence Factor ◽

Fractal Model ◽

Fibrous Materials ◽

Permeability Model ◽

Fractal Modeling ◽

Fibrous Porous Media ◽

Future Work

Permeability is an important hydraulic parameter for characterizing heat and mass transfer properties of fibrous porous media. However, it is difficult to be quantitatively predicted due to the complex and irregular pore structure of fibrous porous media. Fractal geometry has been verified to be an effective method for determining the permeability of fibrous porous media. In this study, recent works on the permeability of fibrous porous media by means of fractal geometry are reviewed, the advances for each presented fractal model are analyzed and summarized, parameter equations used in available fractal permeability models are also briefly compared and reviewed. Future work for more generalized permeability model of fibrous porous media need to conducted by considering the special characters of fibrous materials, uniform pore structure parameter model and the influence factor of capillary pressure, electrokinetic phenomena, etc.

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Predicting the Performance of the Acid-Stimulation Treatments in Carbonate Reservoirs With Nondestructive Tracer Tests

SPE Journal ◽

10.2118/174084-pa ◽

2015 ◽

Vol 20 (06) ◽

pp. 1238-1253 ◽

Cited By ~ 14

Author(s):

A.S.. S. Zakaria ◽

H.A.. A. Nasr-El-Din ◽

M.. Ziauddin

Keyword(s):

Porous Media ◽

Pore Structure ◽

Carbonate Rocks ◽

Tracer Tests ◽

Structure Characterization ◽

Hydrochloric Acid Concentration ◽

Thin Sections ◽

Characterization Methods ◽

Core Samples ◽

Flow Through

Summary Carbonate formations are very complex in their pore structure and exhibit a wide variety of pore classes, such as interparticle porosity, moldic porosity, vuggy porosity, and microporosity. Geologists have defined carbonate pore classes on the basis of sedimentology, thin sections, and porosity/permeability relationships, but the question remains concerning how these pore classes govern the acid flow through porous media. Core samples from six different carbonates, mainly limestone, were selected for the study. The samples were first investigated with thin-section analysis, high-pressure mercury-injection tests, and nuclear-magnetic-resonance measurements for pore-structure characterization, and X-ray diffraction for mineralogy examination. Next, tracer experiments were conducted, and the tracer-concentration profiles were analyzed to quantify the carbonate pore-scale heterogeneity. The heterogeneity is expressed with a parameter f—the available fraction of pore structure contributing to the flow. The data were used to study the flow of acid through carbonate rocks and correlate the pore classes to the acid response. More than 30 acid-coreflood experiments were conducted at 150°F and a hydrochloric acid concentration of 15 wt% on 1.5 × 6-in. core samples at different injection rates on each carbonate rock type. The objective of these sets of experiments is to determine the acid pore volume to breakthrough for each carbonate pore class. The findings of this study help us to connect the results from different characterization methods to the acid flow through the porous media of carbonate rocks. It was also found that the response of the acid depends on the carbonate pore classes. Application to the design of matrix acid treatments in carbonate rocks is discussed.

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