This paper investigates the near-field performance of chemical dissolution-front instability(CDFI) around a circular acidinjection-well in fluid-saturated porous media(FSPM) through using purely mathematical deduction...This paper investigates the near-field performance of chemical dissolution-front instability(CDFI) around a circular acidinjection-well in fluid-saturated porous media(FSPM) through using purely mathematical deductions.After the mathematical governing equations of the CDFI problem involving radially divergent flow are briefly described,both analytical base solutions and perturbation solutions for the considered problem are mathematically derived.These analytical solutions lead to the theoretical expression of the perturbation induced dimensionless growth-rate and the following two new findings.The first new finding is that the critical Peclet number of a chemical dissolution system(CDS) associated with radially divergent flow in FSPM is not only a function of the permeability ratio between the undissolved and dissolved regions as well as the dimensionless wavenumber,but also a function of the circular chemical dissolution-front location relative to the circular acid-injection-well in FSPM.The second new finding is that as the direct result of considering a nonzero radius of the circular acid-injection-well,there exits a critical closeness number,which may be used to assess where the circular chemical dissolution-front starts becoming unstable in the CDS associated with radially divergent flow.Based on these two new findings,a theoretical criterion of two parts has been established.The first part of the established theoretical criterion answers the scientific question when a circular chemical dissolution-front can become unstable,while the second part of the established theoretical criterion answers the scientific question where a circular chemical dissolution-front can become unstable.Through applying the established theoretical criterion,a long-term existing mystery why the wormhole pattern of fractal nature and the compact pattern of fingering nature are formed at different locations away from the circular acid-injection-well circumference in fluid-saturated carbonate rocks has been successfully revealed.展开更多
In this paper, we are interested by the dissolution of NAPL (Non-Aqueous Phase Liquid) contaminants in heterogeneous soils or aquifers. The volume averaging technique is applied to 2D systems with Darcy-scale heteroge...In this paper, we are interested by the dissolution of NAPL (Non-Aqueous Phase Liquid) contaminants in heterogeneous soils or aquifers. The volume averaging technique is applied to 2D systems with Darcy-scale heterogeneities. A large-scale model is derived from a Darcy-scale dissolution model in the case of small and large Damkholer numbers, i.e., for smooth or sharp dissolution fronts. The resulting models in both cases have the mathematical structure of a non-equilibrium dissolution model. It is shown how to calculate the resulting mass exchange and relative permeability terms from the Darcy-scale heterogeneities and other fluid properties. One of the important finding is that the obtained values have a very different behavior compared to the Darcy-scale usual correlations. The large scale correlations are also very different between the two limit cases. The resulting large-scale models are compared favorably to Darcy-scale direct simulations.展开更多
A new surfactant of Gemini-type,N,N'-((phthylbis(oxy))bis(ethane-2,1-diyl))bis(N,N-dimethyldodecan-1-aminium bromide)is prepped&confirmed.The dissolution suppression impact of the new compound on steel is perf...A new surfactant of Gemini-type,N,N'-((phthylbis(oxy))bis(ethane-2,1-diyl))bis(N,N-dimethyldodecan-1-aminium bromide)is prepped&confirmed.The dissolution suppression impact of the new compound on steel is performed in 1 mol·L^(-1)HCl environment by means of chemical and electrochemical methods.The prepared surfactant is an agreeable dissolution inhibitor for steel.The mitigation efficacy rises with the quantity of the compound.The surfactant belongs to inhibitors of mixed-type.The adsorption of the synthesized compound followed the Langmuir's model.The negative magnitudes of bothΔG_(ads)^(θ) andΔH^(adsθ)indicate that the adsorption process proceeds from its own accord and exothermic.The mechanism of adsorption is elucidated by scanning microscopy.It is established that the transfer resistance(R_(ct))value rose,where the value of the phase element(CPE)reduced with the amount of synthesized inhibitor.According to the experimental data arrived by surface tension measurements,the prepared compound is a powerful active agent at the air/water boundary.展开更多
This study aims to investigate methyl tert-butyl ether(MTBE) dissolution in saturated porous media.A series of1 D column experiments were conducted in laboratory to obtain MTBE dissolution data with different groundwa...This study aims to investigate methyl tert-butyl ether(MTBE) dissolution in saturated porous media.A series of1 D column experiments were conducted in laboratory to obtain MTBE dissolution data with different groundwater velocity,initial MTBE saturation and grain size of porous medium,and in the presence of other nonaqueous liquids.Results indicate that higher groundwater velocity increases MTBE dissolution rate and higher initial MTBE saturation reduces effective permeability to slow MTBE dissolution rate.Smaller grain size medium gives higher MTBE dissolution rate because of higher permeability.The addition of trichloroethylene enhances MTBE dissolution,with an optimal mass ratio of 10:2,while the presence of p-xylene prolongs complete dissolution of MTBE.Mass transfer correlations are developed for MTBE dissolution rate based on the degree of MTBE saturation Sn.Mass transfer rate is characterized by Re' with a high exponent for 0.3000<Sn<0.5482,while it is related to medium grain size and Sn for Sn≤0.3000.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos.42030809 and 72088101)。
文摘This paper investigates the near-field performance of chemical dissolution-front instability(CDFI) around a circular acidinjection-well in fluid-saturated porous media(FSPM) through using purely mathematical deductions.After the mathematical governing equations of the CDFI problem involving radially divergent flow are briefly described,both analytical base solutions and perturbation solutions for the considered problem are mathematically derived.These analytical solutions lead to the theoretical expression of the perturbation induced dimensionless growth-rate and the following two new findings.The first new finding is that the critical Peclet number of a chemical dissolution system(CDS) associated with radially divergent flow in FSPM is not only a function of the permeability ratio between the undissolved and dissolved regions as well as the dimensionless wavenumber,but also a function of the circular chemical dissolution-front location relative to the circular acid-injection-well in FSPM.The second new finding is that as the direct result of considering a nonzero radius of the circular acid-injection-well,there exits a critical closeness number,which may be used to assess where the circular chemical dissolution-front starts becoming unstable in the CDS associated with radially divergent flow.Based on these two new findings,a theoretical criterion of two parts has been established.The first part of the established theoretical criterion answers the scientific question when a circular chemical dissolution-front can become unstable,while the second part of the established theoretical criterion answers the scientific question where a circular chemical dissolution-front can become unstable.Through applying the established theoretical criterion,a long-term existing mystery why the wormhole pattern of fractal nature and the compact pattern of fingering nature are formed at different locations away from the circular acid-injection-well circumference in fluid-saturated carbonate rocks has been successfully revealed.
文摘In this paper, we are interested by the dissolution of NAPL (Non-Aqueous Phase Liquid) contaminants in heterogeneous soils or aquifers. The volume averaging technique is applied to 2D systems with Darcy-scale heterogeneities. A large-scale model is derived from a Darcy-scale dissolution model in the case of small and large Damkholer numbers, i.e., for smooth or sharp dissolution fronts. The resulting models in both cases have the mathematical structure of a non-equilibrium dissolution model. It is shown how to calculate the resulting mass exchange and relative permeability terms from the Darcy-scale heterogeneities and other fluid properties. One of the important finding is that the obtained values have a very different behavior compared to the Darcy-scale usual correlations. The large scale correlations are also very different between the two limit cases. The resulting large-scale models are compared favorably to Darcy-scale direct simulations.
基金Foundation ttem Project C. B. 10.00. GL. 03 at Idaho National LaboratoryAcknowledgements This work is supported by the laboratory directed research and development （LDRD） project C. B. 10.00. GL. 03 at Idaho National Laboratory （INL）, which is operated by the Battelle Energy Alliance for the U. S. Department of Energy.
文摘A new surfactant of Gemini-type,N,N'-((phthylbis(oxy))bis(ethane-2,1-diyl))bis(N,N-dimethyldodecan-1-aminium bromide)is prepped&confirmed.The dissolution suppression impact of the new compound on steel is performed in 1 mol·L^(-1)HCl environment by means of chemical and electrochemical methods.The prepared surfactant is an agreeable dissolution inhibitor for steel.The mitigation efficacy rises with the quantity of the compound.The surfactant belongs to inhibitors of mixed-type.The adsorption of the synthesized compound followed the Langmuir's model.The negative magnitudes of bothΔG_(ads)^(θ) andΔH^(adsθ)indicate that the adsorption process proceeds from its own accord and exothermic.The mechanism of adsorption is elucidated by scanning microscopy.It is established that the transfer resistance(R_(ct))value rose,where the value of the phase element(CPE)reduced with the amount of synthesized inhibitor.According to the experimental data arrived by surface tension measurements,the prepared compound is a powerful active agent at the air/water boundary.
基金Supported by the National Natural Science Foundation of China(41201497)
文摘This study aims to investigate methyl tert-butyl ether(MTBE) dissolution in saturated porous media.A series of1 D column experiments were conducted in laboratory to obtain MTBE dissolution data with different groundwater velocity,initial MTBE saturation and grain size of porous medium,and in the presence of other nonaqueous liquids.Results indicate that higher groundwater velocity increases MTBE dissolution rate and higher initial MTBE saturation reduces effective permeability to slow MTBE dissolution rate.Smaller grain size medium gives higher MTBE dissolution rate because of higher permeability.The addition of trichloroethylene enhances MTBE dissolution,with an optimal mass ratio of 10:2,while the presence of p-xylene prolongs complete dissolution of MTBE.Mass transfer correlations are developed for MTBE dissolution rate based on the degree of MTBE saturation Sn.Mass transfer rate is characterized by Re' with a high exponent for 0.3000<Sn<0.5482,while it is related to medium grain size and Sn for Sn≤0.3000.
