Sodium silicate（NazSiO3） was used to improve the elution of super heavy oil from weathered soil on an ultrasound-enhanced elution system by the solution containing 0-6000 mg/L surfactant Triton X-100. The removal ex...Sodium silicate（NazSiO3） was used to improve the elution of super heavy oil from weathered soil on an ultrasound-enhanced elution system by the solution containing 0-6000 mg/L surfactant Triton X-100. The removal extent of three markers[C26-34 17a 25-norhopanes, C26-28triaromatic steroids（TAS）, and C27-29methyl triaromatic steroids（MTAS）] was monitored. The average elution percentages of C26-34 norhopanes, C26-28 TAS, and C27-29 MTAS by Triton X-100/Na2SiO3 solutions were increased by 11%-13%, 9%-11% and 8%-13% with increasing Triton X-100 concentrations from 150 mg/L to 6000 mg/L. All the concentrations of Triton X-100 improved the elu- tion of TAS homologs containing fewer carbon atoms, whereas high concentrations improved the elution of larger 17a 25-norhopane and MTAS species. Addition of Na2SiO3 produced a noticeable increase in elution, particularly for lower-weight species. Scanning electron microscope（SEM） images and energy spectroscopy data reveal that surfac- rant solution of 6000 mg/L Triton X-100 and 4000 mg/L Na2SiO3 produced the greatest improvement in the elution of super heavy oil aggregates encapsulating the soil surface and the emulsification of particle dispersions. That is to say mixed solutions of Triton X-100 and Na2SiO3 in combination with ultrasound are a potential means of removing super heavy oil from weathered soils.展开更多
The drag-reducing characteristics of a cationic surfactant solution flow in copper pipe have been investigated experimentally.The tested drag-reducing fluid was an aqueous solution of the cationic surfactant cetyltrim...The drag-reducing characteristics of a cationic surfactant solution flow in copper pipe have been investigated experimentally.The tested drag-reducing fluid was an aqueous solution of the cationic surfactant cetyltrimethyl ammonium chloride(CTAC).The experimental results show that the maximum drag reduction percentage reduces with the increase of fluid temperature at low concentration of CTAC,such as 100×10-6 or 150×10-6.Furthermore,the concentration and temperature changes of CTAC solution have significant influences on the drag-reducing ability.The drag-reducing effect of CTAC additives shows great potentials in the application in a district heating/cooling(DHC)system,especially for the radiant floor heating(RFH)system.展开更多
Effects of non-Newtonian viscosity for surfactant solution on the vortex characteristics and drag-reducing rate in a swirling pipe flow are investigated by pressure drop measurements, velocity profile measurements and...Effects of non-Newtonian viscosity for surfactant solution on the vortex characteristics and drag-reducing rate in a swirling pipe flow are investigated by pressure drop measurements, velocity profile measurements and viscosity measurements. Non-Newtonian viscosity is represented by power-law model （t= kD^π）. Surfactant solution used has shear-thinning viscosity with n 〈 1.0. The swirling flow in this study has decay of swirl and vortex-type change from Rankin＇s combined vortex to forced vortex. It is shown that the effect of shear-thinning viscosity on the decay of swirl intensity is different by vortex category and the critical swirl number with the vortex-type change depends on shear-thinning viscosity.展开更多
The solid-phase extraction（SPE） technique applied to the extraction of organic compound was creatively used as the extraction of inorganic gold in the paper.Two types of techniques were proposed and explored,namely ...The solid-phase extraction（SPE） technique applied to the extraction of organic compound was creatively used as the extraction of inorganic gold in the paper.Two types of techniques were proposed and explored,namely the SPE and the liquid–liquid extraction（LLE） of the quaternary ammonium surfactant [cetytrimethyl ammonium bromide（CTMAB）,cetyl pyridine bromide（CPB）,benzyl dimethyl dodecyl ammonium chloride（BDMDAC）,and dodecyl trimethyl ammonium chloride（DTMAC）].The surfactant could react with Au（CN）2^- to form the ionic complex,and the compound could be extracted by SPE column of reversed-phase bonded silica gel.Hence,a new method of SPE was proposed to extract gold with these features of the high selectivity,the reliability,and the simplicity.The experimental result shows that the recovery rate of gold is more than 98 %,and the solid-phase extraction column is not easily damaged and it can be repeatedly used.The new method can be used as the extraction process of gold from alkaline cyanide solution as well.Besides,the paper also puts forward a new process of gold extraction.展开更多
The shear viscosity of turbulent drag-reducing surfactant solution was measured as a function of concentration, shear rate and temperature by using an AG-G2 rheometer （TA Instruments, New Castle, USA）. The experimen...The shear viscosity of turbulent drag-reducing surfactant solution was measured as a function of concentration, shear rate and temperature by using an AG-G2 rheometer （TA Instruments, New Castle, USA）. The experimental results showed complicated rheological behavior with the concentration in large. The Bird-Carreau model was found to fit well to the measured rheological results. The characteristics for the parameters ηo-ηx and λ dependence on temperature were also studied.展开更多
Surfactant flooding is a common chemical method for enhancing oil recovery.Recently,the simultaneous application of nanoparticles and chemical substances has been considered for improving the efficiency of EOR process...Surfactant flooding is a common chemical method for enhancing oil recovery.Recently,the simultaneous application of nanoparticles and chemical substances has been considered for improving the efficiency of EOR processes.In the present study,the microscopic and macroscopic efficiency of oil recovery in a linear micromodel in three injection cases of Sodium dodecyl sulfate(SDS)as an anionic surfactant,SiO_(2) nanoparticles,and simultaneous injection of nanoparticles and surfactant was investigated.In our study,adding the nanoparticles along with SDS(2000 ppm)decreased Interfacial tension by 84%,while the figure was 74%and only 10%when the surfactant and the nanoparticles were used alone,respectively.Seemingly,although the nanoparticles alone could not reduce IFT values,adding them to surfactant solution could strongly decrease the interfacial tension between oil and water,leading to enhancement of oil recovery.However,our findings showed that an optimum concentration of nanoparticles in surfactant solution must be used.In this regard,in low concentrations of nanoparticles,they were attached to the interface and IFT decreased due to absorption process.Nevertheless,in high concentrations,nanoparticles removed the surfactant from aqueous phase resulting in no free surfactant available in the bulk.Therefore,surfactant effectiveness in reducing IFT and alteration wettability decreased,and as a consequence,oil recovery efficiency dropped compared to lower nanoparticles’concentrations.Moreover,the results of sessile drop experiments and wettability measurements revealed that coating with either the surfactants or the nanoparticles could partially alter the wettability of surface to water-wet,while coating with the surfactants along with the nanoparticles could make a strongly water-wet surface.Seemingly,investigating the microscopic images of pores and throats showed a strong water-wet condition when the surfactant along with the nanoparticles was used.In addition,the results of flooding tests demonstrated that adding the nanoparticles to surfactant solution could increase the ultimate oil recovery significantly.Moreover,microscopic images confirmed that adding the nanoparticles to the surfactant solution can lead to forming oil-in-water and water-in-oil micro-emulsions due to ultra-low IFT.Obviously,this can result in improving the effectiveness of injection fluid to influence a wider range of porous media.展开更多
基金Supported by the National Natural Science Foundation of China(Nos.51179001 and 40772146)the Fok Ying Tung Education Foundation,China(No.122041)
文摘Sodium silicate（NazSiO3） was used to improve the elution of super heavy oil from weathered soil on an ultrasound-enhanced elution system by the solution containing 0-6000 mg/L surfactant Triton X-100. The removal extent of three markers[C26-34 17a 25-norhopanes, C26-28triaromatic steroids（TAS）, and C27-29methyl triaromatic steroids（MTAS）] was monitored. The average elution percentages of C26-34 norhopanes, C26-28 TAS, and C27-29 MTAS by Triton X-100/Na2SiO3 solutions were increased by 11%-13%, 9%-11% and 8%-13% with increasing Triton X-100 concentrations from 150 mg/L to 6000 mg/L. All the concentrations of Triton X-100 improved the elu- tion of TAS homologs containing fewer carbon atoms, whereas high concentrations improved the elution of larger 17a 25-norhopane and MTAS species. Addition of Na2SiO3 produced a noticeable increase in elution, particularly for lower-weight species. Scanning electron microscope（SEM） images and energy spectroscopy data reveal that surfac- rant solution of 6000 mg/L Triton X-100 and 4000 mg/L Na2SiO3 produced the greatest improvement in the elution of super heavy oil aggregates encapsulating the soil surface and the emulsification of particle dispersions. That is to say mixed solutions of Triton X-100 and Na2SiO3 in combination with ultrasound are a potential means of removing super heavy oil from weathered soils.
基金Sponsored by the National Nature Science Foundation of China(Grant No.50908064)the Ph.D. Programs Foundation of Ministry of Education of China(Grant No.20090460912)
文摘The drag-reducing characteristics of a cationic surfactant solution flow in copper pipe have been investigated experimentally.The tested drag-reducing fluid was an aqueous solution of the cationic surfactant cetyltrimethyl ammonium chloride(CTAC).The experimental results show that the maximum drag reduction percentage reduces with the increase of fluid temperature at low concentration of CTAC,such as 100×10-6 or 150×10-6.Furthermore,the concentration and temperature changes of CTAC solution have significant influences on the drag-reducing ability.The drag-reducing effect of CTAC additives shows great potentials in the application in a district heating/cooling(DHC)system,especially for the radiant floor heating(RFH)system.
文摘Effects of non-Newtonian viscosity for surfactant solution on the vortex characteristics and drag-reducing rate in a swirling pipe flow are investigated by pressure drop measurements, velocity profile measurements and viscosity measurements. Non-Newtonian viscosity is represented by power-law model （t= kD^π）. Surfactant solution used has shear-thinning viscosity with n 〈 1.0. The swirling flow in this study has decay of swirl and vortex-type change from Rankin＇s combined vortex to forced vortex. It is shown that the effect of shear-thinning viscosity on the decay of swirl intensity is different by vortex category and the critical swirl number with the vortex-type change depends on shear-thinning viscosity.
基金financially supported by the National Natural Science Foundation of China (No.20471051.)
文摘The solid-phase extraction（SPE） technique applied to the extraction of organic compound was creatively used as the extraction of inorganic gold in the paper.Two types of techniques were proposed and explored,namely the SPE and the liquid–liquid extraction（LLE） of the quaternary ammonium surfactant [cetytrimethyl ammonium bromide（CTMAB）,cetyl pyridine bromide（CPB）,benzyl dimethyl dodecyl ammonium chloride（BDMDAC）,and dodecyl trimethyl ammonium chloride（DTMAC）].The surfactant could react with Au（CN）2^- to form the ionic complex,and the compound could be extracted by SPE column of reversed-phase bonded silica gel.Hence,a new method of SPE was proposed to extract gold with these features of the high selectivity,the reliability,and the simplicity.The experimental result shows that the recovery rate of gold is more than 98 %,and the solid-phase extraction column is not easily damaged and it can be repeatedly used.The new method can be used as the extraction process of gold from alkaline cyanide solution as well.Besides,the paper also puts forward a new process of gold extraction.
基金the National Natural Science Foundation of China (Grant No. 50476016)the Feasibility Study on the Application of Innovation Energy Conservation Technology in the Large Cities in Eastern Asia (Grant No. 50611140359).
文摘The shear viscosity of turbulent drag-reducing surfactant solution was measured as a function of concentration, shear rate and temperature by using an AG-G2 rheometer （TA Instruments, New Castle, USA）. The experimental results showed complicated rheological behavior with the concentration in large. The Bird-Carreau model was found to fit well to the measured rheological results. The characteristics for the parameters ηo-ηx and λ dependence on temperature were also studied.
文摘Surfactant flooding is a common chemical method for enhancing oil recovery.Recently,the simultaneous application of nanoparticles and chemical substances has been considered for improving the efficiency of EOR processes.In the present study,the microscopic and macroscopic efficiency of oil recovery in a linear micromodel in three injection cases of Sodium dodecyl sulfate(SDS)as an anionic surfactant,SiO_(2) nanoparticles,and simultaneous injection of nanoparticles and surfactant was investigated.In our study,adding the nanoparticles along with SDS(2000 ppm)decreased Interfacial tension by 84%,while the figure was 74%and only 10%when the surfactant and the nanoparticles were used alone,respectively.Seemingly,although the nanoparticles alone could not reduce IFT values,adding them to surfactant solution could strongly decrease the interfacial tension between oil and water,leading to enhancement of oil recovery.However,our findings showed that an optimum concentration of nanoparticles in surfactant solution must be used.In this regard,in low concentrations of nanoparticles,they were attached to the interface and IFT decreased due to absorption process.Nevertheless,in high concentrations,nanoparticles removed the surfactant from aqueous phase resulting in no free surfactant available in the bulk.Therefore,surfactant effectiveness in reducing IFT and alteration wettability decreased,and as a consequence,oil recovery efficiency dropped compared to lower nanoparticles’concentrations.Moreover,the results of sessile drop experiments and wettability measurements revealed that coating with either the surfactants or the nanoparticles could partially alter the wettability of surface to water-wet,while coating with the surfactants along with the nanoparticles could make a strongly water-wet surface.Seemingly,investigating the microscopic images of pores and throats showed a strong water-wet condition when the surfactant along with the nanoparticles was used.In addition,the results of flooding tests demonstrated that adding the nanoparticles to surfactant solution could increase the ultimate oil recovery significantly.Moreover,microscopic images confirmed that adding the nanoparticles to the surfactant solution can lead to forming oil-in-water and water-in-oil micro-emulsions due to ultra-low IFT.Obviously,this can result in improving the effectiveness of injection fluid to influence a wider range of porous media.
