带电性黏土介质多离子体系扩散模型
|
摘要
污染物在黏土防渗层中扩散时,不仅需考虑污染物离子自身活性,还须考虑黏土介质自身带负电特性这一离子存在环境对扩散进程的影响。通过对电场作用下的活度系数进行修正并引入电化学势描述方程,建立了适用于带电性黏土介质的基于动量平衡的多离子体系扩散模型。由于所建模型的复杂性,选用多物理场仿真软件COMSOL Multiphysics开展数值模拟,揭示了多离子体系在黏土垫层中的运动规律。数值结果表明:随着污染物离子初始浓度的增大,考虑土体带电特性及离子活性对扩散进程的阻滞效果越来越明显。
When the contaminant diffuses in the clay impermeable layer, it is necessary to study not only the activity of the contaminant ions, but also the influence of clay materials carried with negative charge on the diffusion process of contaminant ions. In this study the activity coefficient was modified under the action of electric field and the electrochemical potential description equation was introduced, finally a multi-ion system diffusion model for charged clay media was proposed based on momentum balance. The finite element software COMSOL Multiphysics was used to conduct numerical simulation to reveal the motion law of multi-ion system in clay liner. The numerical results show that the block effects considering charged clay and ions activity on diffusion process become more and more obvious with the increase of initial concentration of contaminant ions.
When the contaminant diffuses in the clay impermeable layer, it is necessary to study not only the activity of the contaminant ions, but also the influence of clay materials carried with negative charge on the diffusion process of contaminant ions. In this study the activity coefficient was modified under the action of electric field and the electrochemical potential description equation was introduced, finally a multi-ion system diffusion model for charged clay media was proposed based on momentum balance. The finite element software COMSOL Multiphysics was used to conduct numerical simulation to reveal the motion law of multi-ion system in clay liner. The numerical results show that the block effects considering charged clay and ions activity on diffusion process become more and more obvious with the increase of initial concentration of contaminant ions.
引文
[1] 谢海建,严华祥,张春华,等.考虑固结、扩散和降解耦合作用下污染物大黏土中的运移解析模型[J].水利学报,2015,46(S1):124-128.
[2] 郝风田,路影.海工环境混凝土中氯离子扩散敏感性分析[J].水利与建筑工程学报,2013,11(6):190-207.
[3] 李仁民,刘松玉,缪林昌.黏土中多离子体系的扩散机理研究[J].岩土工程学报,2010,32(11):2-6.
[4] 巨占莹.基于动量平衡的多离子体系在带电性黏土中的扩散模型[D].北京:北京工业大学,2017.
[5] Du Yanjun, Liu Songyu, Hayashi Shigenori. Some factors controlling diffusive transport of potassium ion through clayey soils[J]. Journal of Southeast University: English Edition, 2006,22(1):106-111.
[6] 席永慧,任杰,胡中雄.污染物离子在黏土介质中扩散系数的测定[J].同济大学学报,2003,31(5):595-599.
[7] 陈云敏,谢海建,柯瀚,等.层状土中污染物的一维扩散解析解[J].岩土工程学报,2006,28(4):521-524.
[8] 谢海建,唐晓武,陈云敏,等.原始土层影响下成层介质污染物一维扩散模型[J].浙江大学学报(工学版),2006,40(12):2191-2195.
[9] Xie Haijian, Hywel Rhys Thomas, Chen Yunmin, et al. Diffusion of organic contaminants in triple-layer composite liners:an analytical modeling approach[J]. Acta Geotechnica, 2015,10(2):255-262.
[10] 巨占莹,张志红.考虑组分活度的多组分污染物扩散模型[J].长江科学院院报,2018,35(8):67-71.
[11] 张志红,陈杨,巨占莹,等.基于动量平衡的多离子体系扩散模型[J].水利与建筑工程学报,2018,16(5):87-91.
[12] Rhue D. Coupled diffusion of exchangeable cations in soil[J]. Soil Science Society of America Journal, 1992,56(3):683-689.
[13] 韩光泽,尚永,陈明东.外场作用下多组分质量传递Maxwell-Stefan方程及其应用:电场作用下球形颗粒中的扩散[J].化工学报,2012,63(2):416-423.
[14] Rollea Massimo, Muniruzzaman Muhammad, Haberer Christina M, et al. Coulombic effects in advection-dominated transport of electrolytes in porous media: Multicomponent ionic dispersion[J]. Geochimica et Cosmochimica Acta, 2013,120:195-205.
[15] Muniruzzamana Muhammad, Haberer Christina M., Grathwohl Peter, etal. Multicomponent ionic dispersion during transport of electrolytes in heterogeneous porous media: Experiments and model-based interpretation[J]. Geochimica et Cosmochimica Acta, 2014,141:656-659.
[16] 朱敏.一维多组分溶质运移模型研究[D].北京:北京工业大学,2015.
[2] 郝风田,路影.海工环境混凝土中氯离子扩散敏感性分析[J].水利与建筑工程学报,2013,11(6):190-207.
[3] 李仁民,刘松玉,缪林昌.黏土中多离子体系的扩散机理研究[J].岩土工程学报,2010,32(11):2-6.
[4] 巨占莹.基于动量平衡的多离子体系在带电性黏土中的扩散模型[D].北京:北京工业大学,2017.
[5] Du Yanjun, Liu Songyu, Hayashi Shigenori. Some factors controlling diffusive transport of potassium ion through clayey soils[J]. Journal of Southeast University: English Edition, 2006,22(1):106-111.
[6] 席永慧,任杰,胡中雄.污染物离子在黏土介质中扩散系数的测定[J].同济大学学报,2003,31(5):595-599.
[7] 陈云敏,谢海建,柯瀚,等.层状土中污染物的一维扩散解析解[J].岩土工程学报,2006,28(4):521-524.
[8] 谢海建,唐晓武,陈云敏,等.原始土层影响下成层介质污染物一维扩散模型[J].浙江大学学报(工学版),2006,40(12):2191-2195.
[9] Xie Haijian, Hywel Rhys Thomas, Chen Yunmin, et al. Diffusion of organic contaminants in triple-layer composite liners:an analytical modeling approach[J]. Acta Geotechnica, 2015,10(2):255-262.
[10] 巨占莹,张志红.考虑组分活度的多组分污染物扩散模型[J].长江科学院院报,2018,35(8):67-71.
[11] 张志红,陈杨,巨占莹,等.基于动量平衡的多离子体系扩散模型[J].水利与建筑工程学报,2018,16(5):87-91.
[12] Rhue D. Coupled diffusion of exchangeable cations in soil[J]. Soil Science Society of America Journal, 1992,56(3):683-689.
[13] 韩光泽,尚永,陈明东.外场作用下多组分质量传递Maxwell-Stefan方程及其应用:电场作用下球形颗粒中的扩散[J].化工学报,2012,63(2):416-423.
[14] Rollea Massimo, Muniruzzaman Muhammad, Haberer Christina M, et al. Coulombic effects in advection-dominated transport of electrolytes in porous media: Multicomponent ionic dispersion[J]. Geochimica et Cosmochimica Acta, 2013,120:195-205.
[15] Muniruzzamana Muhammad, Haberer Christina M., Grathwohl Peter, etal. Multicomponent ionic dispersion during transport of electrolytes in heterogeneous porous media: Experiments and model-based interpretation[J]. Geochimica et Cosmochimica Acta, 2014,141:656-659.
[16] 朱敏.一维多组分溶质运移模型研究[D].北京:北京工业大学,2015.