scholarly journals Remediation efficiency of vapour extraction of sandy soils contaminated with cyclohexane: Influence of air flow rate, water and natural organic matter content

2006 ◽  
Vol 143 (1) ◽  
pp. 146-152 ◽  
Author(s):  
José Tomás Albergaria ◽  
Maria da Conceição M. Alvim-Ferraz ◽  
Cristina Delerue-Matos
Keyword(s):  
Organic Matter ◽  
Natural Organic Matter ◽  
Flow Rate ◽  
Air Flow ◽  
Organic Matter Content ◽  
Sandy Soils ◽  
Matter Content ◽  
Air Flow Rate ◽  
Remediation Efficiency ◽  
Vapour Extraction

scholarly journals Toluene Removal from Sandy Soils via In Situ Technologies with an Emphasis on Factors Influencing Soil Vapor Extraction

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Mohammad Mehdi Amin ◽  
Mohammad Sadegh Hatamipour ◽  
Fariborz Momenbeik ◽  
Heshmatollah Nourmoradi ◽  
Marzieh Farhadkhani ◽  
...  
Keyword(s):  
Removal Efficiency ◽  
Flow Rate ◽  
Air Flow ◽  
Sandy Soils ◽  
Air Injection ◽  
Combination Method ◽  
Soil Vapor Extraction ◽  
Air Flow Rate ◽  
Vapor Extraction ◽  
Toluene Removal

The integration of bioventing (BV) and soil vapor extraction (SVE) appears to be an effective combination method for soil decontamination. This paper serves two main purposes: it evaluates the effects of soil water content (SWC) and air flow rate on SVE and it investigates the transition regime between BV and SVE for toluene removal from sandy soils. 96 hours after air injection, more than 97% removal efficiency was achieved in all five experiments (carried out for SVE) including 5, 10, and 15% for SWC and 250 and 500 mL/min for air flow rate on SVE. The highest removal efficiency (>99.5%) of toluene was obtained by the combination of BV and SVE (AIBV: Air Injection Bioventing) after 96 h of air injection at a constant flow rate of 250 mL/min. It was found that AIBV has the highest efficiency for toluene removal from sandy soils and can remediate the vadose zone effectively to meet the soil guideline values for protection of groundwater.

scholarly journals Studi Pendahuluan Pengolahan Air Payau Menjadi Air Bersih Dengan Metode Kombinasi Elektrokoagulasi Dan Adsorpsi Menggunakan Karbosil

2014 ◽  
Vol 2 (1) ◽  
pp. 1
Author(s):  
Eny Heriani R.N. ◽  
Wasinton Simanjuntak ◽  
Ilim .
Keyword(s):  
Electrical Conductivity ◽  
Organic Matter ◽  
Natural Organic Matter ◽  
Brackish Water ◽  
Adsorption Process ◽  
Organic Matter Content ◽  
Matter Content ◽  
Homogeneous Surface ◽  
Pyrolysis Method ◽  
Electrocoagulation Process

This study was carried out to investigate treatment of brackish water using a combination of electrocoagulation and adsorption using carbosil prepared from rice husk with pyrolysis method. Electrocoagulation was applied with the aim to remove natural organic matter in the sample, using aluminim as electrodes, with the particular purpose to study the effect of potenstials.For this purpose, electrocoagulation experiments were conducted at potential of 4, 6, and 8 volt at fixed contact time of 60 minutes.The performance of the method was defined in term of absorbance reduction at the wavelengths of 254 and 285 nm, since the absorbance at these two wavelenghts was found to correlate well with the amount of organic matter in the water samples. The treated water was then subjected to adsorption process at different contac times of 5. 10, and 15 minutes, and the performance of the process was evaluated in term of electrical conductivity reduction.The results obtained indicate that for electrocoagulation process, the higest reduction of natural organic matter content was achieved using potential of 8 volt, and adsorption porcess of 15 minutes was found to result in reduction of electrical conductivity from 15.13 mS/cm to 10.10 mS/cm.Characterization of the carbosil using SEM/EDX technique revealed that the carbosil has practically homogeneous surface and able to adsorb salt and several other elements from the brackish water. Key words : adsorption, brackish water, carbosil, electrocoagulation

scholarly journals Effects of Ammonia Stripping and Other Physico-Chemical Pretreatments on Anaerobic Digestion of Swine Wastewater

Energies ◽  
2020 ◽  
Vol 13 (13) ◽  
pp. 3413
Author(s):  
Adele Folino ◽  
Paolo Salvatore Calabrò ◽  
Demetrio Antonio Zema
Keyword(s):  
Organic Matter ◽  
Anaerobic Digestion ◽  
Flow Rate ◽  
Biogas Production ◽  
Air Flow ◽  
Ammonia Removal ◽  
Swine Wastewater ◽  
Water Evaporation ◽  
Air Flow Rate ◽  
Chemical Pretreatments

In order to overcome anaerobic digestion (AD) inhibition due to the large nitrogen content of swine wastewater (SW), air stripping (AS) and other chemical and physical pretreatments were applied on raw SW before AD. The efficiency of these pretreatments on both ammonia removal—recovering ammonia salts to be used as fertilizers in agriculture—and the increase of methane production were assessed in batch tests. Since the pH, temperature, and air flow rate heavily influence AS efficiency and the composition of treated SW, these parameters were set individually or in combination. In more detail, the pH was increased from the natural value of SW to 8 or 10, temperature was increased from the room value to 40 °C, and the air flow rate was increased from zero to 5 Lair LSW−1 min−1. AS was generally more efficient at removing ammonia (up to 97%) from raw (non-treated) SW compared to the other treatments. However, the tested pretreatments were not as efficient as expected in increasing the biogas production, because the methane yields of all pretreated substrates were lower (by about 10–50%) to compared raw SW. The inhibitory effect on AD could have been due to the lack of nutrients and organic matter in the substrate (due to the excessive removal of the pretreatments), the concentration of toxic compounds (such as metal ions or furfural due to water evaporation), and an excess of alkali ions (used to increase the pH in AS). Overall, AS can be considered a sustainable process for the recovery of ammonium sulphate and the removal of other polluting compounds (e.g., organic matter) from SW. Conversely, the use of AS and other chemical and/or thermal processes tested in this study as pretreatments of SW before AD is not advised because these processes appear to reduce methane yields.

scholarly journals Short-Term Soil Flushing with Tannic Acid and Its Effect on Metal Mobilization and Selected Properties of Calcareous Soil

2021 ◽  
Vol 18 (11) ◽  
pp. 5698
Author(s):  
Zygmunt Mariusz Gusiatin ◽  
Joeri Kaal ◽  
Agnieszka Wasilewska ◽  
Jurate Kumpiene ◽  
Maja Radziemska
Keyword(s):  
Organic Matter ◽  
Metal Concentration ◽  
Tannic Acid ◽  
Flow Rate ◽  
Metal Removal ◽  
Organic Matter Content ◽  
Exchange Capacity ◽  
Matter Content ◽  
Gas Chromatography Mass Spectrometry ◽  
Soil Flushing

Cadmium, Cu, Ni, Pb, and Zn removal via soil flushing with tannic acid (TA) as a plant biosurfactant was studied. The soil was treated for 30 h in a column reactor at a constant TA concentration and pH (3%, pH 4) and at variable TA flow rates (0.5 mL/min or 1 mL/min). In the soil leachates, pH, electrical conductivity (EC), total dissolved organic carbon, and metal concentrations were monitored. Before and after flushing, soil pH, EC, organic matter content, and cation exchange capacity (CEC) were determined. To analyze the organic matter composition, pyrolysis as well as thermally assisted hydrolysis and methylation coupled with gas chromatography-mass spectrometry were used. Metal fractionation in unflushed and flushed soil was analyzed using a modified sequential extraction method. The data on cumulative metal removal were analyzed using OriginPro 8.0 software (OriginLab Corporation, Northampton, MA, USA) and were fitted to 4-parameter logistic sigmoidal model. It was found that flushing time had a stronger influence on metal removal than flow rate. The overall efficiency of metal removal (expressed as the ratio between flushed metal concentration and total metal concentration in soil) at the higher flow rate decreased in this order: Cd (86%) > Ni (44%) > Cu (29%) ≈ Zn (26%) > Pb (15%). Metals were removed from the exchangeable fraction and redistributed into the reducible fraction. After flushing, the soil had a lower pH, EC, and CEC; a higher organic matter content; the composition of the organic matter had changed (incorporation of TA structures). Our results prove that soil flushing with TA is a promising approach to decrease metal concentration in soil and to facilitate carbon sequestration in soil.

scholarly journals Corn yield in sandy soil fertilized with poultry litter

2018 ◽  
pp. 921
Author(s):  
Juliana da Silva Barros ◽  
João Carlos Medeiros ◽  
Jaqueline Dalla Rosa ◽  
Julian Junio de Jesus Lacerda, Daiane Conceição de Sousa ◽  
Maria Sueli Heberle Mafra
Keyword(s):  
Organic Matter ◽  
Sandy Soil ◽  
Organic Fertilizer ◽  
Poultry Litter ◽  
Organic Matter Content ◽  
Chemical Properties ◽  
Sandy Soils ◽  
Matter Content ◽  
Soil Chemical Properties ◽  
Corn Yield

The use of animal waste is an alternative to provide nutrients and increase organic matter content in sandy soils. The poultry litter is one of the most nutrient-rich residues. The objective of this study was assess the effect of poultry litter as organic fertilizer on productivity of corn and chemical properties of a sandy soil. The experiment was conducted at the experimental farm of the Federal University of Piauí, in the municipality of Bom Jesus, PI, Brazil. The treatments were poultry litter levels: 0 (control), 2, 4, 8, 12, 16 and 24 t ha-1. We evaluated the effect of poultry litter on the soil chemical properties, plant growth and productivity of corn. We also evaluated the correlation between variables of the plant and soil chemical properties. The maximum productivity was obtained with the highest level poultry litter (24 t ha-1). Calcium, magnesium, phosphorus, potassium, pH, and soil organic matter increased due to the increase of poultry litter levels. The soil chemical properties have positive relationship with stem diameter and productivity of corn. The poultry litter is an organic fertilizer with potential of increase the productivity of the corn and meliorate the fertility of sandy soils.

Evaluation of centrifugal ultrafilters for size fractionation of total mercury and methylmercury in freshwaters

2013 ◽  
Vol 10 (4) ◽  
pp. 323 ◽  
Author(s):  
David Kocman ◽  
Scott C. Brooks ◽  
Carrie L. Miller ◽  
Xiangping L. Yin
Keyword(s):  
Organic Matter ◽  
Natural Organic Matter ◽  
Total Mercury ◽  
Organic Matter Content ◽  
Matter Content ◽  
Contaminated Water ◽  
Size Fractionation ◽  
East Fork Poplar Creek ◽  
Total Hg ◽  
Nominal Molecular Weight

Environmental context Although mercury associated with colloids is an important part of the aquatic Hg cycle, there is currently no fast and reliable method to separate complexes smaller than traditional filter pore sizes. We test commercially available centrifugal ultrafilters for their applicability to size fractionation of total Hg and methylmercury in freshwaters. Sorption of Hg onto the filters precludes their use for fractionation of inorganic Hg, the approach proved to be very suitable for methylmercury fractionation regardless of sample organic matter content. Abstract Amicon Ultra-15 centrifugal filters with nominal molecular weight cut-offs of 100, 30 and 3kDa, were tested for separating Hg complexes in freshwaters. Experiments used Hg-contaminated water from East Fork Poplar Creek (EFPC) and laboratory-prepared Hg solutions containing Suwannee River natural organic matter (SR-NOM). Investigations focussed on Hg and dissolved organic carbon blank levels, Hg sorption and leaching, Hg mass balance closure and spike recoveries of inorganic and methylmercury (MeHg). Hg spike recoveries for EFPC samples were low (57±16%, n=30) due to sorption. MeHg recovery averaged 87±9% (n=15) suggesting it was less affected by sorptive losses. SR-NOM samples yielded similar dissolved organic matter (DOM) and MeHg size fractionation patterns with ~20% of the MeHg found in the less than 3-kDa fraction. Overall, the distribution of MeHg followed a pattern similar to the DOM, indicating the importance of both sample DOM quantity and quality for MeHg partitioning in aquatic systems. Although the use of these ultrafilters for inorganic Hg in freshwater samples is not recommended, they were successfully used for MeHg in EFPC where the majority of MeHg was found to be either dissolved or associated with phases smaller than 3kDa.

Use of GAC after enhanced coagulation for the removal of natural organic matter from water for purification

2009 ◽  
Vol 9 (2) ◽  
pp. 173-180 ◽  
Author(s):  
I. García ◽  
L. Moreno
Keyword(s):  
Organic Matter ◽  
Natural Organic Matter ◽  
Environmental Protection Agency ◽  
Organic Matter Content ◽  
The United States ◽  
Matter Content ◽  
Protection Agency ◽  
Enhanced Coagulation ◽  
Water Plant ◽  
Anionic Charge

Filtration with granular activated carbon (GAC) after an enhanced coagulation (EC) process was evaluated in order to determine the effectiveness of GAC in the reduction of natural organic matter (NOM), which should result in much lower formation of trihalomethane in the disinfection step. The results show that a combination of EC and GAC considerably reduces the organic matter content, which is mainly fulvic acid. This type of organic matter is removed with high coagulant dosages which neutralize their high anionic charge. A further reduction of NOM is achieved due the adsorption of NOM by GAC. As a result, the average trihalomethane (THM) concentration was only 14.5±5 μg L−1. Enhanced coagulation alone decreased the NOM concentration by 50%, but the remaining NOM reacted in the chlorination step and a higher average THM concentration was found (38±23 μg L−1). An average THM concentration of 73.8±41.2 μg L−1 was found at the drinking water plant of Boaco when conventional treatment was used. This THM concentration sometimes exceeds the maximum contaminant level of 80 μg L−1 established by the United States Environmental Protection Agency (USEPA), but not the Nicaraguan threshold of 460 μg L−1.

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