Removal of Diesel Oil in Soil Microcosms and Implication for Geophysical Monitoring

Bioremediation of soils polluted with diesel oil is one of the methods already applied on a large scale. However, several questions remain open surrounding the operative conditions and biological strategies to be adopted to optimize the removal efficiency. This study aimed to investigate the environmental factors that influence geophysical properties in soil polluted with diesel oils, in particular, during the biodegradation of this contaminant by an indigenous microbial population. With this aim, aerobic degradation was performed in soil column microcosms with a high concentration of diesel oil (75 g kg−1 of soil); the dielectric permittivity and electrical conductivity were measured. In one of the microcosms, the addition of glucose was also tested. Biostimulation was performed with a Mineral Salt Medium for Bacteria. The sensitivity of the dielectric permittivity versus temperature was analyzed. A theoretical approach was adopted to estimate the changes in the bulk dielectric permittivity of a mixture of sandy soil-water-oil-gas, according to the variations in the oil content. The sensitivity of the dielectric permittivity to the temperature effects was analyzed. The results show that (1) biostimulation can give good removal efficiency; (2) the addition of glucose as a primary carbon source does not improve the diesel oil removal; (3) a limited amount of diesel oil was removed by adsorption and volatilization effects; and (4) the diesel oil efficiency removal was in the order of 70% after 200 days, with different removal percentages for oil components; the best results were obtained for molecules with a low retention time. This study is preparatory to the adoption of geophysical methods to monitor the biological process on a larger scale. Altogether, these results will be useful to apply the process on a larger scale, where geophysical methods will be adopted for monitoring.

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Integrated use of chemical and geophysical monitoring to study the diesel oil biodegradation in microcosms with different operative conditions

Journal of Environmental Health Science and Engineering ◽

10.1007/s40201-021-00681-2 ◽

2021 ◽

Author(s):

Carla Maria Raffa ◽

Andrea Vergnano ◽

Fulvia Chiampo ◽

Alberto Godio

Keyword(s):

Dielectric Permittivity ◽

Water Content ◽

Removal Efficiency ◽

Diesel Oil ◽

Coaxial Cable ◽

Imaginary Component ◽

Oil Removal ◽

Oil Biodegradation ◽

Dry Soil ◽

Two Parameters

AbstractThis study aimed to monitor the aerobic bioremediation of diesel oil-contaminated soil by measuring: a) the CO2 production; 2) the fluorescein production; 3) the residual diesel oil concentration. Moreover, the complex dielectric permittivity was monitored through an open-ended coaxial cable. Several microcosms were prepared, changing the water content (u% = 8–15% by weight), the carbon to nitrogen ratio (C/N = 20–450), and the soil amount (200 and 800 g of dry soil). The cumulative CO2 and fluorescein production showed similar trends, but different values since these two parameters reflect different features of the biological process occurring within each microcosm. The diesel oil removal efficiency depended on the microcosm characteristics. After 84 days, in the microcosms with 200 g of dry soil, the highest removal efficiency was achieved with a water content of 8% by weight and C/N = 120, while in the microcosms with 800 g of dry soil the best result was achieved with the water content equal to 12% by weight and C/N = 100. In the tested soil, the bioremediation process is efficient if the water content is in the range 8–12% by weight, and C/N is in the range 100–180; under these operative conditions, the diesel oil removal efficiency was about 65–70% after 84 days. The dielectric permittivity was monitored in microcosms with 200 g of dry soil. The open-ended coaxial cable detected significant variations of both the real and the imaginary component of the dielectric permittivity during the bioremediation process, due to the physical and chemical changes that occurred within the microcosms.

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Geochemical and Mineralogical Characterisation of Historic Zn–Pb Mine Waste, Plombières, East Belgium

Minerals ◽

10.3390/min11010028 ◽

2020 ◽

Vol 11 (1) ◽

pp. 28

Author(s):

Srećko Bevandić ◽

Rosie Blannin ◽

Jacqueline Vander Auwera ◽

Nicolas Delmelle ◽

David Caterina ◽

...

Keyword(s):

Grain Size ◽

Mine Waste ◽

Geophysical Methods ◽

Grain Size Analysis ◽

Size Analysis ◽

Mine Wastes ◽

Metallurgical Waste ◽

High Concentration ◽

Geochemical Properties ◽

Potential Applications

Mine wastes and tailings derived from historical processing may contain significant contents of valuable metals due to processing being less efficient in the past. The Plombières tailings pond in eastern Belgium was selected as a case study to determine mineralogical and geochemical characteristics of the different mine waste materials found at the site. Four types of material were classified: soil, metallurgical waste, brown tailings and yellow tailings. The distribution of the mine wastes was investigated with drill holes, pit-holes and geophysical methods. Samples of the materials were assessed with grain size analysis, and mineralogical and geochemical techniques. The mine wastes dominantly consist of SiO2, Al2O3 and Fe2O3. The cover material, comprising soil and metallurgical waste is highly heterogeneous in terms of mineralogy, geochemistry and grain size. The metallurgical waste has a high concentration of metals (Zn: 0.1 to 24 wt.% and Pb: 0.1 to 10.1 wt.%). In the tailings materials, Pb and Zn vary from 10 ppm to 8.5 wt.% and from 51 ppm to 4 wt.%, respectively. The mining wastes comprises mainly quartz, amorphous phases and phyllosilicates, with minor contents of Fe-oxide and Pb- and Zn-bearing minerals. Based on the mineralogical and geochemical properties, the different potential applications of the four waste material types were determined. Additionally, the theoretical economic potential of Pb and Zn in the mine wastes was estimated.

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Start-up Strategies for Anaerobic Ammonia Oxidation (Anammox) in In-Situ Nitrogen Removal from Polluted Groundwater in Rare Earth Mining Areas

Sustainability ◽

10.3390/su13084591 ◽

2021 ◽

Vol 13 (8) ◽

pp. 4591

Author(s):

Shuanglei Huang ◽

Daishe Wu

Keyword(s):

Rare Earth ◽

Low Temperature ◽

Removal Efficiency ◽

Nitrogen Removal ◽

Ex Situ ◽

High Concentration ◽

Low Concentration ◽

Start Up ◽

Anammox Activity

The tremendous input of ammonium and rare earth element (REE) ions released by the enormous consumption of (NH4)2SO4 in in situ leaching for ion-adsorption RE mining caused serious ground and surface water contamination. Anaerobic ammonium oxidation (anammox) was a sustainable in situ technology that can reduce this nitrogen pollution. In this research, in situ, semi in situ, and ex situ method of inoculation that included low-concentration (0.02 mg·L−1) and high-concentration (0.10 mg·L−1) lanthanum (La)(III) were adopted to explore effective start-up strategies for starting up anammox reactors seeded with activated sludge and anammox sludge. The reactors were refrigerated for 30 days at 4 °C to investigate the effects of La(III) during a period of low-temperature. The results showed that the in situ and semi in situ enrichment strategies with the addition of La(III) at a low-concentration La(III) addition (0.02 mg·L−1) reduced the length of time required to reactivate the sludge until it reached a state of stable anammox activity and high nitrogen removal efficiency by 60–71 days. The addition of La(III) promoted the formation of sludge floc with a compact structure that enabled it to resist the adverse effects of low temperature and so to maintain a high abundance of AnAOB and microbacterial community diversity of sludge during refrigeration period. The addition of La(III) at a high concentration caused the cellular percentage of AnAOB to decrease from 54.60 ± 6.19% to 17.35 ± 6.69% during the enrichment and reduced nitrogen removal efficiency to an unrecoverable level to post-refrigeration.

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Joint Gravity and Seismic Reflection Methods to Characterize the Deep Aquifers in Arid Ain El Beidha Plain (Central Tunisia, North Africa)

Water ◽

10.3390/w13091310 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1310

Author(s):

Hajer Azaiez ◽

Hakim Gabtni ◽

Mourad Bédir

Keyword(s):

Seismic Reflection ◽

Large Scale ◽

Seismic Analysis ◽

Gravity Data ◽

Geophysical Methods ◽

Gravity Anomalies ◽

Integrated Approach ◽

Central Tunisia ◽

Deep Aquifers ◽

Advanced Analysis

Electric resistivity sounding and tomography, as well as electromagnetic sounding, are the classical methods frequently used for hydrogeological studies. In this work, we propose the development and implementation of an original integrated approach using the unconventional hydro–geophysical methods of gravity and seismic reflection for the fast, large–scale characterization of hydrogeological potential using the Ain El Beidha plain (central Tunisia) as an analogue. Extending the values of vintage petroleum seismic reflection profiles and gravity data, in conjunction with available geological and hydrogeological information, we performed an advanced analysis to characterize the geometry of deep tertiary (Oligocene and Eocene) aquifers in this arid area. Residual and tilt angle gravity maps revealed that most gravity anomalies have a short wavelength. The study area was mainly composed of three major areas: the Oued Ben Zitoun and Ain El Beidha basins, which are both related to negative gravity trends corresponding to low–density subsiding depocenters. These basins are separated by an important NE–SW trend called “El Gonna–J. El Mguataa–Kroumet Zemla” gravity high. Evaluation of the superposition of detected lineaments and Euler deconvolution solutions’ maps showed several NE–SW and N–S relay system faults. The 3D density inversion model using a lateral and vertical cutting plane suggested the presence of two different tectonic styles (thin VS thick). Results from the gravity analysis were in concordance with the seismic analysis. The deep Oligocene and Eocene seismic horizons were calibrated to the hydraulic wells and surrounding outcrops. Oligocene and Eocene geological reservoirs appear very fractured and compartmented. The faulting network also plays an important role in enhancing groundwater recharge process of the Oligocene and Eocene aquifers. Finally, generated isochron maps provided an excellent opportunity to develop future comprehensive exploration surveys over smaller and more favorable areas’ sub–basins.

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Experimental Study on the Optimal Thickness of Infiltration Media of the CRI System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.415-417.1703 ◽

2011 ◽

Vol 415-417 ◽

pp. 1703-1707

Author(s):

Jun Min Chen ◽

Xiao Lin Yao

Keyword(s):

Experimental Study ◽

Removal Efficiency ◽

Significant Influence ◽

Soil Column ◽

Experimental Results ◽

Artificial Soil ◽

Optimal Thickness ◽

Effluent Quality ◽

Anaerobic Zone

Abstract. In order to investigate the optimal thickness of infiltration media in the Constructed Rapid Infiltration System, the artificial soil column is used to simulate the Constructed Rapid Infiltration System, and the CODCr, NH3-N and TN concentrations of the effluent from all the sampling sites are monitored. The experimental results and analysis show that the thickness of infiltration media exerts a significant influence on the CODCr, NH3-N and TN concentration and removal efficiency of the effluent; the CODCr, NH3-N and TN are mainly removed in the 0-1800mm zone of the artificial soil column; the total CODCr removal efficiency increases, as the thickness of infiltration media increases, but the CODCr removal efficiency in the 1800-2200mm zone is very low; the NH3-N and TN removal efficiency reaches the maximum where the thickness of infiltration media is 1800mm; the NH3-N and TN concentration of the effluent from 1800-2200mm zone dose not decrease, but increase 5-8%, due to the assimilation denitrification and amemoniation reaction on the end of the anaerobic zone; in consideration of the effluent quality, efficient biodegradation zone, construction investment, etc. the optimal thickness of infiltration media in CRI system should be 1800mm.

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Response surface methodology approach for the optimisation of adsorption of hydrolysed polyacrylamide from polymer-flooding wastewater onto steel slag: a good option of waste mitigation

Water Science & Technology ◽

10.2166/wst.2017.245 ◽

2017 ◽

Vol 76 (4) ◽

pp. 776-784 ◽

Cited By ~ 2

Author(s):

Mijia Zhu ◽

Jun Yao ◽

Zhonghai Qin ◽

Luning Lian ◽

Chi Zhang

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Removal Efficiency ◽

Contact Time ◽

Interactive Effect ◽

Steel Slag ◽

Oxygen Demand ◽

Polymer Flooding ◽

High Concentration ◽

Adsorbent Dosage

Wastewater produced from polymer flooding in oil production features high viscosity and chemical oxygen demand because of the residue of high-concentration polymer hydrolysed polyacrylamide (HPAM). In this study, steel slag, a waste from steel manufacturing, was studied as a low-cost adsorbent for HPAM in wastewater. Optimisation of HPAM adsorption by steel slag was performed with a central composite design under response surface methodology (RSM). Results showed that the maximum removal efficiency of 89.31% was obtained at an adsorbent dosage of 105.2 g/L, contact time of 95.4 min and pH of 5.6. These data were strongly correlated with the experimental values of the RSM model. Single and interactive effect analysis showed that HPAM removal efficiency increased with increasing adsorbent dosage and contact time. Efficiency increased when pH was increased from 2.6 to 5.6 and subsequently decreased from 5.6 to 9.3. It was observed that removal efficiency significantly increased (from 0% to 86.1%) at the initial stage (from 0 min to 60 min) and increased gradually after 60 min with an adsorbent dosage of 105.2 g/L, pH of 5.6. The adsorption kinetics was well correlated with the pseudo-second-order equation. Removal of HPAM from the studied water samples indicated that steel slag can be utilised for the pre-treatment of polymer-flooding wastewater.

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Tectonic state and oil-gas prospects of Khidirly-Bandovan structure according to the new gravimetric data

Azerbaijan Oil Industry ◽

10.37474/0365-8554/2020-6-7-11-18 ◽

2020 ◽

pp. 11-18

Author(s):

A.S. Hasanov ◽

◽

Keyword(s):

Geophysical Methods ◽

Geological Mapping ◽

Seismic Exploration ◽

Huge Amount ◽

Ray Method ◽

Common Depth Point ◽

Geophysical Surveys ◽

Gravimetric Data ◽

Exploration Drilling ◽

Oil Gas

Khidirly-Bandovan structures have been studied through geological mapping, structural exploration drilling, geophysical methods (gravimetric, magnetic, electrical, seismic exploration methods) since the 1930s. Small amount of oil from different wells in the upper part of Productive Series (PS) and huge amount of gas fountain from Middle Absheron sediments have been obtained. As the interest to these areas had not decreased, the geophysical surveys continued during further years. Seismic exploration surveys were executed in Bandovan structure via Common Depth Point (CDP) method in 2004, refracted ray method and gravimetric exploration complex in 2006 and 3D seismic exploration works and gravimetric investigations with “Scintrex CG-5 Autograv” devices in 2016, correspondingly. In the result of analysis of distribution characteristics for local gravimetric anomalies, as well as 3D descriptions of new gravimetric data, up-to-date logs on tectonic state of Khidirly-Bandovan structure have been obtained and as the new oil-gas exploration objects, the west and south-west wings of these structures highlighted.

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Anaerobic treatment and biogas recovery for sago wastewater management using a fluidized bed reactor

Water Science & Technology ◽

10.2166/wst.2001.0360 ◽

2001 ◽

Vol 44 (6) ◽

pp. 141-147 ◽

Cited By ~ 13

Author(s):

R. Saravanane ◽

D. V.S. Murthy ◽

K. Krishnaiah

Keyword(s):

Fluidized Bed ◽

Large Scale ◽

Fluidized Bed Reactor ◽

Anaerobic Treatment ◽

Solid Content ◽

Treated Wastewater ◽

Maximum Efficiency ◽

Cow Dung ◽

Wastewater Management ◽

High Concentration

Starch manufacturing industrial units, such as sago mills, both at medium and large scale, suffer from inadequate treatment and disposal problems due to high concentration of suspended solid content present in the effluent. In order to investigate the viability of treatment of sago effluent, a laboratory scale study was conducted. The treatment of sago effluent was studied in a continuous flow anaerobic fluidized bed reactor. The start-up of the reactor was carried out using a mixture of digested supernatant sewage sludge and cow dung slurry in different proportions. The effect of operating variables such as COD of the effluent, bed expansion, minimum fluidization velocity on efficiency of treatment and recovery of biogas was investigated. The treated wastewater was analysed for recycling and reuse to ensure an alternative for sustainable water resourse management. The maximum efficiency of treatment was found to be 82% and the nitrogen enriched digested sludge was recommended for agricultural use.

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Subsurface characterization of a quick-clay vulnerable area using near-surface geophysics and hydrological modelling

Solid Earth ◽

10.5194/se-10-1685-2019 ◽

2019 ◽

Vol 10 (5) ◽

pp. 1685-1705

Author(s):

Silvia Salas-Romero ◽

Alireza Malehmir ◽

Ian Snowball ◽

Benoît Dessirier

Keyword(s):

Large Scale ◽

Geophysical Methods ◽

Hydrological Modelling ◽

P Wave ◽

Coarse Grained ◽

Near Surface ◽

Reflection Seismic ◽

Geotechnical Investigations ◽

Quick Clay ◽

Near Surface Geophysics

Abstract. Quick-clay landslides are common geohazards in Nordic countries and Canada. The presence of potential quick clays is confirmed using geotechnical investigations, but near-surface geophysical methods, such as seismic and resistivity surveys, can also help identify coarse-grained materials associated with the development of quick clays. We present the results of reflection seismic investigations on land and in part of the Göta River in Sweden, along which many quick-clay landslide scars exist. This is the first time that such a large-scale reflection seismic investigation has been carried out to study the subsurface structures associated with quick-clay landslides. The results also show a reasonable correlation with radio magnetotelluric and travel-time tomography models of the subsurface. Other ground geophysical data, such as high magnetic values, suggest a positive correlation with an increased thickness of the coarse-grained layer and shallower depths to the top of the bedrock and the top of the coarse-grained layer. The morphology of the river bottom and riverbanks, e.g. subaquatic landslide deposits, is shown by side-scan sonar and bathymetric data. Undulating bedrock, covered by subhorizontal sedimentary glacial and postglacial deposits, is clearly revealed. An extensive coarse-grained layer (P-wave velocity mostly between 1500 and 2500 m s−1 and resistivity from approximately 80 to 100 Ωm) exists within the sediments and is interpreted and modelled in a regional context. Several fracture zones are identified within the bedrock. Hydrological modelling of the coarse-grained layer confirms its potential for transporting fresh water infiltrated in fractures and nearby outcrops located in the central part of the study area. The modelled groundwater flow in this layer promotes the leaching of marine salts from the overlying clays by seasonal inflow–outflow cycles and/or diffusion, which contributes to the formation of potential quick clays.

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Micro-pressure swirl reactor (MPSR) for efficient COD and nitrogen removal of high-concentration wastewater

Water Science & Technology ◽

10.2166/wst.2020.454 ◽

2020 ◽

Vol 82 (9) ◽

pp. 1795-1807 ◽

Cited By ~ 1

Author(s):

Dejun Bian ◽

Zebing Nie ◽

Fan Wang ◽

Shengshu Ai ◽

Suiyi Zhu ◽

...

Keyword(s):

Removal Efficiency ◽

Nitrogen Removal ◽

Lower Cost ◽

Batch Reactor ◽

Oxygen Demand ◽

Swirl Flow ◽

High Concentration ◽

Internal Circulation ◽

Carbon And Nitrogen ◽

Pressure Swirl

Abstract A micro-pressure swirl reactor (MPSR) was developed for carbon and nitrogen removal of wastewater, in which dissolved oxygen (DO) gradient and internal circulation could be created by setting the aerators along one side of the reactor, and micro-pressure could be realized by sealing most of the top cap and increasing the outlet water level. In this study, velocity and DO distribution in the reactor was measured, removal performance treating high-concentration wastewater was investigated, and the main functional microorganisms were analyzed. The experiment results indicated that there was stable swirl flow and spatial DO gradient in MPSR. Operated in sequencing batch reactor mode, distinct biological environments spatially and temporally were created. Under the average influent condition of chemical oxygen demand (COD) concentration of 2,884 mg/L and total nitrogen (TN) of 184 mg/L, COD removal efficiency and removal loading was 98% and 1.8 kgCOD/(m3·d) respectively, and TN removal efficiency and removal loading reached up to 90% and 0.11 kgTN/(m3·d) respectively. With efficient utilization of DO and simpler configuration for simultaneous nitrification and denitrification, the MPSR has the potential of treating high-concentration wastewater at lower cost.

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