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Influence of Colloids on Mineralization in Unconventional Oil and Gas Reservoirs and Wellbores
Published in Olayinka I. Ogunsola, Isaac K. Gamwo, Solid–Liquid Separation Technologies, 2022
J. Alexandra Hakala, Wei Xiong, Justin Mackey, Meghan Brandi, James Gardiner, Nicholas Siefert, Christina Lopano, Barbara Kutchko, B.J. Carney
Reaction path models performed with GWB for Scenario 1 showed that the major saturated phases (SI>0) included witherite (BaCO3), barite (BaSO4), strontianite (SrCO3), SiO2 phases (quartz, tridymite, chalcedony, and cristobalite), dolomite (CaMg(CO3)2), and CaCO3 phases (calcite, aragonite) (Table 11.4). Multiple clay and clay-like phases were also calculated with SI>0 (kaolinite, muscovite, saponite-Ca for the thermo.dat- based calculation; mesolite, muscovite, nontronite-Ca, and nontronite-Mg for the V8.R6-based calculation) as a result of the HFF-shale reaction (Table 11.4). Calculation with the V8.R6 database also showed SI>0 for manganese oxide (pyrolusite) and aluminum oxyhydroxide (diaspore) (Table 11.4).
A Constructed Wetland System for Treatment of Landfill Leachate, Monroe County, New York
Published in George Mulamoottil, Edward A. McBean, Frank Rovers, Constructed Wetlands for the Treatment of Landfill Leachates, 2018
David A.V. Eckhardt, Jan M. Surface, John H. Peverly
Barium, which can be present as colloidal hydroxides and oxides (Hem, 1985), was not efficiently removed, apparently because barium from witherite (barium carbonate) in the SSF beds was being released into solution. As a result, the median dissolved and median total barium concentrations at the SSF outflow exceeded the respective median values at the SF inflow, The total barium load in the inflow decreased only 49%, but the dissolved barium load actually increased (Table 13.2). The median dissolved barium concentration in the SSF outflow was 0.38 mg/L, which exceeds by about a factor of 3 the solubility equilibrium for barite (barium sulfate). In the presence of 10 mg/L of sulfate, which is the median sulfate concentration in the SSF-bed outflow, the equilibrium barium concentration is 0.14 mg/L (Sillen and Martell, 1964). Thus, barium was probably released from witherite, and possibly barite, in the SSF substrate. Barium concentrations in the outflow did not exceed the state limit of 1 mg/L, however.
Sources of Hazardous Waste
Published in Patrick V. Brady, Michael V. Brady, David J. Borns, Natural Attenuation, 2018
Patrick V. Brady, Michael V. Brady, David J. Borns
Barium (Ba) is used in oil and gas drilling muds, and consequently shows up in oilfield waste inventories, where it is present as relatively insoluble sulfate minerals. Barium is also used in plastics, pesticides, a variety of oils and fuels, and in a number of medical treatments. Exposure to high levels of barium causes vomiting, diarrhea, and paralysis. Barium exists as Ba2+ in sub-alkaline solutions. At pH >9 BaCO3 ion pairs form. In sulfate-rich solutions the BaSO4 ion pair forms. The solids barium sulfate and barium carbonate (respectively barite and witherite) are very insoluble, and grow rapidly. Ba levels in solution are also limited by its appreciable adsorption to clays. The net effect of low solubility (given the right conditions) and non-trivial sorption is that Ba moves very slowly through soils. Although barium is taken up by aquatic organisms and plants, there appears to be little biomagnification in the latter (Smith et al., 1995). The MCL for Ba is 2 ppm.
Use of Triple-Exposure X-ray Computed Tomography for Nondestructive Identification of Heavy Elements in Soil Samples
Published in Soil and Sediment Contamination: An International Journal, 2021
We consider soil and sediment contamination by naturally occurring heavy minerals at sites near ore deposits (e.g. Hoshino et al. 2020; McGrath, Zhang, and Carton 2004; Noerpel et al. 2020; Obasi 2020; Ohta et al. 2005; Tabelin et al. 2018; Ujiie-Mikoshiba et al. 2006; Vreča, Pirc, and Šajn 2001; Zhang et al. 2012) in the present study. Thus, in addition to the Cav values for the simple substance, those for galena (PbS), witherite (BaCO3), stibnite (Sb2S3), sphalerite (ZnS), magnetite (Fe3O4), native sulfur (S8), and quartz (SiO2) were also calculated. Galena, witherite, and stibnite are hazardous minerals. Galena was chosen because lead is the target heavy element in the present study. Witherite, stibnite, native sulfur, and quartz were chosen because their constituents, namely Ba, Sb, S, and Si, yield Cav ratios that are nearly equal to that of Pb, and thus may cause ambiguity. Sphalerite was chosen because it often occurs with galena in ore deposits (e.g. Lambert and Sato 1974). Magnetite was chosen because it is one of the most common heavy-element-containing minerals in the crust and yields bright voxels in reconstructed CT images (e.g. Falvard and Paris 2017; Nakashima and Komatsubara 2018), possibly causing ambiguity.
Strength development and microstructure properties of slag activated with alkaline earth metal ions: a review study
Published in European Journal of Environmental and Civil Engineering, 2023
Hadi Bahmani, Davood Mostofinejad
The witherite (barium carbonate, BaCO3) observed in the XRD diagram formed when barium was present along with sulfate and carbonate sources (Mobasher et al., 2014), which could be due to the barium hydroxide reacting with calcite. The use of barium hydroxide in the slag samples created a higher pH and the hydrotalcite phase was dependent on the dissolution of Mg ions (Khan & O'Hare, 2002; Shigeo & Teruhiko, 1973). As a result, the barium hydroxide activator caused a greater amount of hydrotalcite phase than other activators (Jeong et al., 2017).