Groundwater contamination becomes a great concern in many countries. One of the most important pollutants is hydrocarbons. Sources of Hydrocarbons pollutants in Gazacan be a result of accidental spills of petroleum pr...Groundwater contamination becomes a great concern in many countries. One of the most important pollutants is hydrocarbons. Sources of Hydrocarbons pollutants in Gazacan be a result of accidental spills of petroleum products on the surface and uncontrolled disposal of wastewater. One of the common technologies for groundwater aquifer remediation from hydrocarbons is known as air sparging. In this study, a120 cm×100 cm×80 cmlaboratory scale aquifer model was implemented in order to investigate the effectiveness of air sparging technology in removal of petroleum products from contaminated site. Four pilot scale wells were installed at different depths and different spatial distribution. The central well was used for injecting air and the surrounding three wells were used for monitoring. The contaminated water and soil were tested for total organic carbon, lead, dissolved Oxygen and pH;one time before the start of treatment and four times through the treatment process. Total organic carbon in water and soil before air injection were 980 ppm and 0.08775 ppm, respectively. After air injection for three weeks (six hours daily) at flow rate range from 15 to20 L/min and at pressure range from 300 to 400 kPa, the concentration of pollutant was decreased to 4.0 ppm and 0.0 ppm in water and soil, respectively. Based on the results, it was clearly demonstrated that air sparging is a simple, effective and affordable technology that can be applied forGazaaquifer remediation in case of gasoline spill accidents.展开更多
BTEX contaminants in groundwater seriously impact the ecological environment and human health that has become one of the urgent problems needed to be solved.Due to its low density,low solubility and strong volatility,...BTEX contaminants in groundwater seriously impact the ecological environment and human health that has become one of the urgent problems needed to be solved.Due to its low density,low solubility and strong volatility,BTEX in groundwater usually form non-aqueous phase liquid(NAPL) contaminants and exist in three phases:gas,aqueous and oil phase.Air sparging(AS) is an in situ treatment technology展开更多
Air sparging is a remedial method for groundwater. The remedial region is similar to the air flow region in the saturated zone. If soil particles are transported during air sparging, the porosity distributions in the ...Air sparging is a remedial method for groundwater. The remedial region is similar to the air flow region in the saturated zone. If soil particles are transported during air sparging, the porosity distributions in the saturated zone change, which may alter the flow path of the air. To understand better the particle movement, this study performed a sandbox test to estimate the soil porosity change during air sparging. A clear fracture was formed and the phenomenon of particle movement was observed when the air injection was started. The moved sand filled the porous around the fracture and the reparked sand filled the fracture, reducing the porosity around the fracture. The results obtained from the photographs of the sandbox, the current measurements and the direct sand sample measurements were close to each other and are credible. Therefore, air injection during air sparging causes sand particle movement of sand, altering the characteristic of the sand matrix and the air distribution.展开更多
Air sparging(AS) is an emerging method to remove VOCs from saturated soils and groundwater. Air sparging performance highly depends on the air distribution resulting in the aquifer. In order to study gas flow characte...Air sparging(AS) is an emerging method to remove VOCs from saturated soils and groundwater. Air sparging performance highly depends on the air distribution resulting in the aquifer. In order to study gas flow characterization, a two-dimensional experimental chamber was designed and installed. In addition, the method by using acetylene as the tracer to directly image the gas distribution results of AS process has been put forward. Experiments were performed with different injected gas flow rates. The gas flow patterns were found to depend significantly on the injected gas flow rate, and the characterization of gas flow distributions in porous media was very different from the acetylene tracing study. Lower and higher gas flow rates generally yield more irregular in shape and less effective gas distributions.展开更多
Oxidation reaction of rare earth chlorides(Ce/Pr/Nd/EuCl3) in a LiCl-KCl eutectic molten salt was carried out using an oxygen sparging method. Regardless of the sparging time and the molten salt temperature, oxychlori...Oxidation reaction of rare earth chlorides(Ce/Pr/Nd/EuCl3) in a LiCl-KCl eutectic molten salt was carried out using an oxygen sparging method. Regardless of the sparging time and the molten salt temperature, oxychlorides (NdOCl, PrOCl) and oxides(CeO, Eu2O3, PrO2) were formed as a oxidation products(i.e. precipitates) by the reaction with oxygen. The conversion efficiency of the rare earth elements to the precipitates increases with the sparging time and the molten salt temperature. In the conditions of 650 ℃ of a molten salt temperature and 420 min of a sparging time, the values of the conversion efficiency of the used rare earth chlorides were over 99.9%. Information on the hydrodynamics of an oxygen-molten salt two phase flow system is essential since its hydrodynamics strongly affect the oxidation reaction of rare earth elements in an eutectic chloride melts.展开更多
The TRU-Vision system,developed by Baker Hughes,analyzes the gas extracted from drilling mud to estimate the hydrocarbons composition in drilled rock formations.Several separation processes had been surveyed in order ...The TRU-Vision system,developed by Baker Hughes,analyzes the gas extracted from drilling mud to estimate the hydrocarbons composition in drilled rock formations.Several separation processes had been surveyed in order to enhance the gas extraction at the gas trap,namely,mechanical stirring,vacuum,air sparging,membrane separation processes,ultrasounds,and cyclones.Mechanical stirring devices(one propeller,one flat-blade turbine,and two baffles sets),a vacuum generator,and an air bubble generator were designed and assembled to increase the efficiency and the response stability of TRU-Vision system.展开更多
文摘Groundwater contamination becomes a great concern in many countries. One of the most important pollutants is hydrocarbons. Sources of Hydrocarbons pollutants in Gazacan be a result of accidental spills of petroleum products on the surface and uncontrolled disposal of wastewater. One of the common technologies for groundwater aquifer remediation from hydrocarbons is known as air sparging. In this study, a120 cm×100 cm×80 cmlaboratory scale aquifer model was implemented in order to investigate the effectiveness of air sparging technology in removal of petroleum products from contaminated site. Four pilot scale wells were installed at different depths and different spatial distribution. The central well was used for injecting air and the surrounding three wells were used for monitoring. The contaminated water and soil were tested for total organic carbon, lead, dissolved Oxygen and pH;one time before the start of treatment and four times through the treatment process. Total organic carbon in water and soil before air injection were 980 ppm and 0.08775 ppm, respectively. After air injection for three weeks (six hours daily) at flow rate range from 15 to20 L/min and at pressure range from 300 to 400 kPa, the concentration of pollutant was decreased to 4.0 ppm and 0.0 ppm in water and soil, respectively. Based on the results, it was clearly demonstrated that air sparging is a simple, effective and affordable technology that can be applied forGazaaquifer remediation in case of gasoline spill accidents.
文摘BTEX contaminants in groundwater seriously impact the ecological environment and human health that has become one of the urgent problems needed to be solved.Due to its low density,low solubility and strong volatility,BTEX in groundwater usually form non-aqueous phase liquid(NAPL) contaminants and exist in three phases:gas,aqueous and oil phase.Air sparging(AS) is an in situ treatment technology
文摘Air sparging is a remedial method for groundwater. The remedial region is similar to the air flow region in the saturated zone. If soil particles are transported during air sparging, the porosity distributions in the saturated zone change, which may alter the flow path of the air. To understand better the particle movement, this study performed a sandbox test to estimate the soil porosity change during air sparging. A clear fracture was formed and the phenomenon of particle movement was observed when the air injection was started. The moved sand filled the porous around the fracture and the reparked sand filled the fracture, reducing the porosity around the fracture. The results obtained from the photographs of the sandbox, the current measurements and the direct sand sample measurements were close to each other and are credible. Therefore, air injection during air sparging causes sand particle movement of sand, altering the characteristic of the sand matrix and the air distribution.
基金The National Natural Science Foundation of China(No. 20276048)
文摘Air sparging(AS) is an emerging method to remove VOCs from saturated soils and groundwater. Air sparging performance highly depends on the air distribution resulting in the aquifer. In order to study gas flow characterization, a two-dimensional experimental chamber was designed and installed. In addition, the method by using acetylene as the tracer to directly image the gas distribution results of AS process has been put forward. Experiments were performed with different injected gas flow rates. The gas flow patterns were found to depend significantly on the injected gas flow rate, and the characterization of gas flow distributions in porous media was very different from the acetylene tracing study. Lower and higher gas flow rates generally yield more irregular in shape and less effective gas distributions.
基金the Nuclear R&D Program by the Korean Ministry of Science and Technology
文摘Oxidation reaction of rare earth chlorides(Ce/Pr/Nd/EuCl3) in a LiCl-KCl eutectic molten salt was carried out using an oxygen sparging method. Regardless of the sparging time and the molten salt temperature, oxychlorides (NdOCl, PrOCl) and oxides(CeO, Eu2O3, PrO2) were formed as a oxidation products(i.e. precipitates) by the reaction with oxygen. The conversion efficiency of the rare earth elements to the precipitates increases with the sparging time and the molten salt temperature. In the conditions of 650 ℃ of a molten salt temperature and 420 min of a sparging time, the values of the conversion efficiency of the used rare earth chlorides were over 99.9%. Information on the hydrodynamics of an oxygen-molten salt two phase flow system is essential since its hydrodynamics strongly affect the oxidation reaction of rare earth elements in an eutectic chloride melts.
文摘The TRU-Vision system,developed by Baker Hughes,analyzes the gas extracted from drilling mud to estimate the hydrocarbons composition in drilled rock formations.Several separation processes had been surveyed in order to enhance the gas extraction at the gas trap,namely,mechanical stirring,vacuum,air sparging,membrane separation processes,ultrasounds,and cyclones.Mechanical stirring devices(one propeller,one flat-blade turbine,and two baffles sets),a vacuum generator,and an air bubble generator were designed and assembled to increase the efficiency and the response stability of TRU-Vision system.
