0086-21-58386256
The influence of acid solution and immersion time on the physicomechanical properties of sandstone is investigated. Uniaxial compression tests on sandstone samples are conducted to determine the ...
The dissolution of sandstone cement causes the fine sandstone particles to fall off and fill the pores; the porosity increased at first but then decreased with acid treatment time.
of sandstone dissolution under the action of dry–wet cycles in acid and alkaline environments Wen Yuan1 & Xinrong Liu1,2 & Yan Fu 3 # Springer-Verlag Germany 2017 Abstract The aim of this paper is to study the mechanism of strength deterioration of sandstone under the action of dry– wet cycles in acid and alkaline environments based …
Clay minerals dominate the cement in the CL lithofacies of tight sandstone. The dissolution mainly occurs in small pores because the precipitation of new minerals and exfoliation of skeleton ...
The dissolution characteristics of quartz in tight sandstone reservoirs are investigated through forward simulation and microscopic image analysis combined with example analysis.
Chemical weathering includes carbonic acid and hydrolysis, dissolution, and oxidation. Erosion is a mechanical process, usually driven by water, wind, gravity, ... In quartz sandstone, sometimes called quartz arenite (SiO 2), ... so the sediment is not subject to daily winnowing and deposition. These sediment layers are typically finely ...
The dynamic peak stress of sandstone is greatly affected by the acid dry-wet cycle, and as the pH of the acidic solution decreases, the elastic modulus and dynamic peak stress …
Understanding the complex flow behavior along a rough-walled fracture under complex chemical conditions is of great significance to deep rock engineering in carbonate rocks. This study investigates the influence of acid dissolution on the nonlinear flow behavior of rough-walled limestone fractures. Fracture flow tests are performed …
In order to investigate the controlling mechanism of temperature, fluid and other factors on water-rock interaction in the diagenetic process, we performed a series of simulated experiments on the interaction between two kinds of fluids with different salinity and a composite mineral system (simulated sandstone), which contains albite, K …
The edge notched disk bend samples were adopted to investigate the degradation response of mode I and mode III fracture resistance of green sandstone under wetting-drying cycles in an acidic solution.
Calcite cemented sandstone is subject to acidic dissolution and is more easily eroded. Clay and gypsum cements, which are soft minerals, tend to produce much softer sandstone and the sand can sometimes be rubbed off in a person's hands. The cementing agents also affect the porosity of a sandstone. When the initial sand is first deposited …
These characteristics present significant technical challenges for exploitation, especially for deep tight sandstone reservoirs, which are subject to ultra-high temperatures, high pressure, and strong stress sensitivity (Hu, ... The effect of …
Request PDF | Chemical thermodynamics and chemical kinetics analysis of sandstone dissolution under the action of dry–wet cycles in acid and alkaline environments | The aim of this paper is to ...
The tunnels affected by the fire will remain in service after restoration and likely be subject to erosion from acidic groundwater. In China, groundwater erosion has become one key factor inducing major disasters threatening the safety of tunnels (Huang et al. 2019; Gu et al. 2020; Huang et al. 2021b).According to the Bulletin on China's …
The seepage capacity of tight sandstone can be improved by acid dissolution. ... These characteristics present significant technical challenges for …
acid in the uranium sandstone during the acid-leaching process, producing precipitation when it reached certain critical conditions. The precipitation may have attached to the particle surface of the
This study investigates the impact of hydro-chemical action on the deterioration of physical and mechanical properties of rock, with a specific focus on sandstone subjected to HCl, and H 2 SO 4 solutions with pH values of 2 and 5. The research explores the role of the surface-area-to-volume (SATV) ratios of 0.65 and 0.70 …
The influence of water–rock interaction in the process of coal mine construction cannot be ignored, especially when the groundwater quality is complex and contains acidic substances. In this paper, considering the influence of mining, blasting, and earthquake, the dynamic mechanical properties and fractal characteristics of sandstone …
Request PDF | On Feb 1, 2024, Yanling Liang and others published Effect of the surface-area-to-volume ratio on dissolution and deterioration of acid-corroded sandstone | Find, read and cite all ...
(2) To reveal the dissolution reaction mechanism between organic acid fluids and tight sandstone, providing a theoretical basis for improving the prediction …
Semantic Scholar extracted view of "Effect of wetting–drying cycles on mode I and mode II fracture toughness of sandstone in natural (pH = 7) and acidic (pH = 3) environments" by A. Dehestani et al.
Different types of interactions take place during the acid injections in the sandstone formations. The main parameters that affect the rock–acid interactions are the sandstone mineralogy and the acid type (Mahmoud and Gomaa, 2022; Shafiq and Mahmud, 2017).In general, sandstone formation composes of two major mineral types: …
(2) To reveal the dissolution reaction mechanism between organic acid fluids and tight sandstone, providing a theoretical basis for improving the prediction ability of relatively high-quality reservoirs under tight backgrounds.
DOI: 10.1016/j.jobe.2024.108789 Corpus ID: 267992033; Effect of the surface-area-to-volume ratio on dissolution and deterioration of acid-corroded sandstone @article{Liang2024EffectOT, title={Effect of the surface-area-to-volume ratio on dissolution and deterioration of acid-corroded sandstone}, author={Yanling Liang and …
Carbonic acid (H 2 CO 3) forms when carbon dioxide, the fifth-most abundant gas in the atmosphere, dissolves in water. This happens naturally in clouds, which is why precipitation is normally slightly acidic. Carbonic acid is an important agent in two chemical weathering reactions, hydrolysis, and dissolution. Hydrolysis occurs via two types of ...
Stimulation of the sandstone reservoir requires a mixture of acids such as mud acid, which assist in enlarging the microscopic paths by dissolving the siliceous fines or clays near the well-bore region. As a result, the formation permeability and porosity can be enhanced. In deeper wells, the temperature exceeds 200 °F, at these temperature …
The physicomechanical deterioration characteristics of sandstone subjected to H2SO4, HCl, and H2O solutions of different pH values are studied by the method of long-term accelerated immersion.
Abstract. Regular mud acid mixtures have been extensively used to stimulate sandstone formations; however, the use of this acid in a deep well has some major drawbacks, including high and uncontrolled reaction rate and corrosion to well tubulars. A single stage sandstone acid system (HF and a phosphonic acid) has been developed …
Limestone is mostly made up of the mineral calcium carbonate (CaCO3). This is not very soluble, so rocks don't dissolve very quickly. But if you add an acid, you add hydrogen ions (H+), which will react with the carbonate to form hydrogen carbonate HCO3- ions, which are very soluble in water, and the limestone will dissolve. Or, if there …
The alkaline solution degrades the rock more than the acid solution, which means that the sandstone is more sensitive to alkaline solutions. ... of sandstone are broken down by dissolution. When ...
The physicomechanical deterioration characteristics of sandstone subjected to H2SO4, HCl, and H2O solutions of different pH values are studied by the method of long-term accelerated immersion.
The Turonian sandstone (sample PT) was also a medium-grained rock dominated by quartz grains and featuring subordinate lithic grains (Fig. 1 B and Fig. S2, Supplementary materials).The median size (Q 2) was 0.09 mm and for the percentiles, Q 1 = 0.04 mm and Q 3 = 0.24 mm. Unlike the Cenomanian sandstone, PT was relatively …
In addition, acid rain, mineral dissolution, acid deposition, and other factors make groundwater acidic. This caused the underground structure to erode and has also threatened its safety and ...
This study examines the corrosion characteristics of weakly cemented sandstone under alkaline conditions, evaluating the effects of varying pH levels on its …
Matrix acidizing is a common technique to increase oil recovery in sandstone oil reservoirs. In the matrix acidizing process, reactive fluids are injected into the reservoir with the scope of dissolving and dispersing the rocks near the wellbore.In this study, the matrix acidizing of sandstone wells by a hydrochloric acid/hydrofluoric acid/additives …
The most imperative target of sandstone matrix acidizing is to dissolve/remove siliceous particles (clay, feldspar and quartz) that restrict the flow of hydrocarbons and reduce permeability around the wellbore (Crowe et al. 1992; Lindsay 1976).This can be achieved by the injection of hydrofluoric acid (HF acid) or its …
[Show full abstract] the effective stress law for permeability in a tight sandstone specimen after acid stimulation. Two dissolution passages, formed due to carbonate mineral dissolution, are ...
Tight sandstone acid treatment is generally carried out using mud acid (HF/HCl), with HF molecules playing a crucial role in sandstone mineral reactions [24]. The acid treatment results in the gradually dissolution of sandstone minerals and cements, leading to an increase in rock porosity and pore connectivity [9]. This increase in
