Adsorption Characteristics and Transport Behavior of Cr(VI) in Shallow Aquifers Surrounding a Chromium Ore Processing Residue (COPR) Dumpsite

This study explored the stratigraphic distribution and soil/shallow aquifer characteristics surrounding a chromium ore processing residue (COPR) dumpsite at a former chemical factory in China. Total Cr levels in top soils (5–10 cm) nearby the COPR dumpsite were in the range of 8571.4–10711.4 mg/kg. Shallow aquifers (1–6 m) nearby the COPR dumpsite showed a maximum total Cr level of 9756.7 mg/kg. The concentrations of Cr(VI) in groundwater nearby the COPR dumpsite were 766.9–1347.5 mg/L. These results display that the top soils, shallow aquifers, and groundwater of the study site are severely polluted by Cr(VI). Then, three aquifers (silt, clay, and silty clay), respectively, collected from the depth of 1.4–2.4 m, 2.4–4.8 m, and 4.8–11.00 m were first used to evaluate the adsorption characteristics and transport behavior of Cr(VI) in shallow aquifers by both batch and column experiments. The adsorption of Cr(VI) on tested aquifers was well described by pseudo-second-order equation and Freundlich model. The adsorption capacities of Cr(VI) on three aquifers followed the order: clay > silty clay > silt. The kinetics proved that Cr(VI) is not easily adsorbed by the aquifer mediums but transports with groundwater. Thermodynamics indicated that Cr(VI) adsorption on tested aquifers was feasible, spontaneous, and endothermic. Cr(VI) adsorption on tested aquifers decreased with increasing pH. Furthermore, the transport of Cr(VI) in adsorption columns followed the sequence of clay < silty clay < silt. Desorption column experiments infer that the Cr(VI) adsorbed on aquifers will desorb and release into groundwater in the case of rainwater leaching. Therefore, a proper treatment of the COPR and a comprehensive management of soils are vital to prevent groundwater pollution.

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A New Analysis Model for Potential Contamination of a Shallow Aquifer from a Hydraulically-Fractured Shale

Energies ◽

10.3390/en11113010 ◽

2018 ◽

Vol 11 (11) ◽

pp. 3010

Author(s):

Weihong Peng ◽

Menglin Du ◽

Feng Gao ◽

Xuan Dong ◽

Hongmei Cheng

Keyword(s):

Migration Time ◽

Shallow Aquifer ◽

Contaminant Migration ◽

Analysis Model ◽

Shallow Aquifers ◽

Shale Formations ◽

Migration Mechanism ◽

Shale Reservoirs ◽

Time Required ◽

The Impact

Hydraulic fracturing (HF) is widely used in shale gas development, which may cause some heavy metals release from shale formations. These contaminants could transport from the fractured shale reservoirs to shallow aquifers. Thus, it is necessary to assess the impact of pollution in shallow aquifers. In this paper, a new analysis model, considering geological distributions, discrete natural fractures (NFs) and faults, is developed to analyze the migration mechanism of contaminants. Furthermore, the alkali erosion of rock caused by high-pH drilling of fluids, is considered in this paper. The numerical results suggest that both NFs and alkali erosion could reduce the time required for contaminants migrating to aquifers. When NFs and alkali erosion are both considered, the migration time will be shortened by 51 years. Alkali erosion makes the impact of NFs, on the contaminant migration, more significant. The migration time decreases with increasing pH values, while the accumulation is on the opposite side. Compared with pH 12.0, the migration time would be increased by 45 years and 29 years for pH 11.0 and 11.5, respectively. However, the migration time for pH 12.5 and 13.0 were found to be decreased by 82 years and 180 years, respectively. Alkali erosion could increase the rock permeability, and the elevated permeability would further enhance the migration velocity of the contaminants, which might play a major role in assessing the potential contamination of shallow aquifers.

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Adsorption Kinetics of Pb2+ Ions Using Chitosan Nanoparticles

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.367.45 ◽

2013 ◽

Vol 367 ◽

pp. 45-49

Author(s):

Ying Hong ◽

Ze Hui Zhong ◽

You Shi Liu

Keyword(s):

Adsorption Kinetics ◽

Chitosan Nanoparticles ◽

Second Order ◽

Isotherm Model ◽

Order Model ◽

Adsorption Characteristics ◽

Pseudo Second Order ◽

Kinetics Of ◽

Second Order Model

Chitosan nanoparticles were prepared by crosslinkingusing TPP. SEM showed that chitosan nanoparticles were successfully obtained.The adsorption characteristics of chitosan nanoparticles were evaluated. Theresults demonstrated that chitosan nanoparticles were suitable for adsorbent toremoval Pb2+. The parameters for the adsorption of Pb2+by chitosan nanoparticles were also determined. It was shown that chitosannanoparticles were fit for Langmuir’s isotherm model and that the adsorptionkinetics of Pb2+ described by the pseudo-second-order model could bebest.

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Complete Reduction of Hazardous Cr(VI) in Chromium Ore Processing Residue Dump Site

Asian Journal of Chemistry ◽

10.14233/ajchem.2018.21060 ◽

2018 ◽

Vol 30 (3) ◽

pp. 620-624 ◽

Cited By ~ 1

Author(s):

Vanitha Murugaiyan ◽

T. Sehar ◽

S. Selvaraj ◽

P. Kamatchi Selvaraj

Keyword(s):

Dump Site ◽

Complete Reduction ◽

Chromium Ore ◽

Ore Processing

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Optimisation of metal extraction from chromium ore processing residue in New Jersey, USA

Journal of Environmental Engineering and Science ◽

10.1680/jenes.18.00009 ◽

2018 ◽

Vol 13 (4) ◽

pp. 98-107

Author(s):

Wiwat Kamolpornwijit ◽

Jay N Meegoda ◽

Janitha H Batagoda

Keyword(s):

New Jersey ◽

Metal Extraction ◽

Chromium Ore ◽

Ore Processing

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Electrical resistivity survey in the investigation of hydrogeological condition of Sylhet-Sunamganj Haor area, Bangladesh

Journal of Nepal Geological Society ◽

10.3126/jngs.v58i0.24570 ◽

2019 ◽

Vol 58 ◽

pp. 21-28

Author(s):

A. S.M. Woobaidullah ◽

S. M. Shahnewaz ◽

Md. Munirul Islam ◽

Md. Kamrul Islam ◽

Md. Zakir Hossain

Keyword(s):

Water Quality ◽

Electrical Resistivity ◽

Shallow Aquifer ◽

Quality Data ◽

Thickness Variation ◽

Silty Clay ◽

Geological Condition ◽

Minimum Thickness ◽

Water Quality Data ◽

Maximum Thickness

Bangladesh depends on the ground water resources to meet domestic and agricultural demands. Electrical Resistivity Sounding survey, borehole litho logs and the water quality data of the area have been analysed for the assessment of subsurface hydro geological condition of the study area, located in north eastern region of Bangladesh. Hydro geological data are needed to determine the basic parameters required for the characterization of aquifer. VES can provide subsurface information related to groundwater condition in conjunction with borehole and water quality information. Resistivity soundings were carried out to establish the characteristics of the aquifer in the study area. Results of resistivity soundings and borehole data reveal that the subsurface formations are made up of clay, silty clay, clayey sand, fine, medium and coarse sands. The hydro stratigraphic unit of the study area comprises of three aquifer systems separated by aquitards. Aquifer-1 known as shallow aquifer, shows thickness in the range from 4 m to 104 m. Maximum thickness of Aquifer-1 is about 104 m at At para, Kishoreganj and minimum thickness is about 4 m at Madan, Netrokona. Aquifer-2 shows thickness variation from 3 m to 135 m. Maximum thickness of Aquifer-2 is about 135 m at Madhabpur, Habiganj and minimum thickness is about 3 m at Bajitpur, Kishoreganj. Baseof Aquifer-3, the deep aquifer could not be identified. Maximum depth of the upper boundary of this unit is about 171 m at Madhabpur,Habiganj and minimum depth is about 100 m at Mohanganj, Netrokona. At Madan, Netrokona low resistivity value of about 7 ohm below 107 m depth is found against a fine to medium sand layer suggesting saline formation water.

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Specific Gravity of Expansive Chromium Ore Processing Residue with Complex Microstructure

Geotechnical Testing Journal ◽

10.1520/gtj102836 ◽

2010 ◽

Vol 33 (4) ◽

pp. 102836 ◽

Cited By ~ 1

Author(s):

L. D. Suits ◽

T. C. Sheahan ◽

Andrew M. Millspaugh ◽

James M. Tinjum ◽

Timothy A. Boecher

Keyword(s):

Specific Gravity ◽

Chromium Ore ◽

Ore Processing

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Designing Aquifer Model for the Banks of the Serayu River, Sokawera, Somagede, Banyumas, Indonesia by Means of 1D-Electrical Resistivity Data

Journal of Mathematical and Fundamental Sciences ◽

10.5614/j.math.fund.sci.2021.53.3.1 ◽

2021 ◽

Vol 53 (3) ◽

pp. 344-357

Author(s):

Sehah Sehah ◽

Hartono Hartono ◽

Zaroh Irayani ◽

Urip Nurwijayanto Prabowo

Keyword(s):

Electrical Resistivity ◽

Model Potential ◽

Research Area ◽

Shallow Aquifer ◽

Shallow Aquifers ◽

Clayey Sand ◽

Deep Aquifer ◽

Resistivity Data ◽

Deep Aquifers ◽

Groundwater Aquifer

A geoelectric survey using the 1D-electrical resistivity method was applied to design a groundwater aquifer model for the banks of the Serayu River in Sokawera Village, Somagede District, Banyumas Regency, Indonesia. The aim of this research was to identify the characteristics of aquifers in the research area based on resistivity log data. Acquisition, modeling, and interpretation of resistivity data were carried out and the results were lithological logs at seven sounding points. Correlation between the lithological logs resulted in a hydrostratigraphic model. This model is composed of several hydrological units, i.e. shallow aquifer, aquitard, and deep aquifer. The shallow aquifers are composed of sandy clay (10.81-18.21 Wm) and clayey sand (3.04-7.43 Wm) with a depth of groundwater from the water table to 27.51 m. The deep aquifers are composed of sandstone with variation of porosity (2.24-12.04 Wm) at a depth of more than 54.98 m. Based on this model, potential shallow aquifers were estimated to be at sounding points Sch-5, Sch-6, and Sch-7. This hydrostratigraphic model shows that the two types of aquifers are separated by an aquitard layer, allowing groundwater infiltration from the shallow aquifer to the deep aquifer and vice versa. Moreover, the Serayu riverbanks in this research area are estimated to be a groundwater discharge area.

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Redox controls on methane formation, migration and fate in shallow aquifers

Hydrology and Earth System Sciences ◽

10.5194/hess-20-2759-2016 ◽

2016 ◽

Vol 20 (7) ◽

pp. 2759-2777 ◽

Cited By ~ 21

Author(s):

Pauline Humez ◽

Bernhard Mayer ◽

Michael Nightingale ◽

Veith Becker ◽

Andrew Kingston ◽

...

Keyword(s):

Shallow Groundwater ◽

Hydrocarbon Exploration ◽

Shallow Aquifer ◽

Shallow Aquifers ◽

Biogenic Origin ◽

Biogenic Methane ◽

Groundwater Samples ◽

Wide Range ◽

Thermogenic Methane

Abstract. Development of unconventional energy resources such as shale gas and coalbed methane has generated some public concern with regard to the protection of groundwater and surface water resources from leakage of stray gas from the deep subsurface. In terms of environmental impact to and risk assessment of shallow groundwater resources, the ultimate challenge is to distinguish (a) natural in situ production of biogenic methane, (b) biogenic or thermogenic methane migration into shallow aquifers due to natural causes, and (c) thermogenic methane migration from deep sources due to human activities associated with the exploitation of conventional or unconventional oil and gas resources. This study combines aqueous and gas (dissolved and free) geochemical and isotope data from 372 groundwater samples obtained from 186 monitoring wells of the provincial Groundwater Observation Well Network (GOWN) in Alberta (Canada), a province with a long record of conventional and unconventional hydrocarbon exploration. We investigated whether methane occurring in shallow groundwater formed in situ, or whether it migrated into the shallow aquifers from elsewhere in the stratigraphic column. It was found that methane is ubiquitous in groundwater in Alberta and is predominantly of biogenic origin. The highest concentrations of biogenic methane (>  0.01 mM or >  0.2 mgL−1), characterized by δ13CCH4 values <  −55 ‰, occurred in anoxic Na-Cl, Na-HCO3, and Na-HCO3-Cl type groundwaters with negligible concentrations of nitrate and sulfate suggesting that methane was formed in situ under methanogenic conditions for 39.1 % of the samples. In only a few cases (3.7 %) was methane of biogenic origin found in more oxidizing shallow aquifer portions suggesting limited upward migration from deeper methanogenic aquifers. Of the samples, 14.1 % contained methane with δ13CCH4 values >  −54 ‰, potentially suggesting a thermogenic origin, but aqueous and isotope geochemistry data revealed that the elevated δ13CCH4 values were caused by microbial oxidation of biogenic methane or post-sampling degradation of low CH4 content samples rather than migration of deep thermogenic gas. A significant number of samples (39.2 %) contained methane with predominantly biogenic C isotope ratios (δ13CCH4 <  −55 ‰) accompanied by elevated concentrations of ethane and sometimes trace concentrations of propane. These gases, observed in 28.1 % of the samples, bearing both biogenic (δ13C) and thermogenic (presence of C3) characteristics, are most likely derived from shallow coal seams that are prevalent in the Cretaceous Horseshoe Canyon and neighboring formations in which some of the groundwater wells are completed. The remaining 3.7 % of samples were not assigned because of conflicting parameters in the data sets or between replicates samples. Hence, despite quite variable gas concentrations and a wide range of δ13CCH4 values in baseline groundwater samples, we found no conclusive evidence for deep thermogenic gas migration into shallow aquifers either naturally or via anthropogenically induced pathways in this baseline groundwater survey. This study shows that the combined interpretation of aqueous geochemistry data in concert with chemical and isotopic compositions of dissolved and/or free gas can yield unprecedented insights into formation and potential migration of methane in shallow groundwater. This enables the assessment of cross-formational methane migration and provides an understanding of alkane gas sources and pathways necessary for a stringent baseline definition in the context of current and future unconventional hydrocarbon exploration and exploitation.

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