低挥发性有机酸不仅自身污染环境而且显著促进颗粒污染物形成,对其吸脱附性能的研究有助于这类物质的控制。采用程序升温脱附（TPD）技术对乙二酸、苯甲酸在活性炭（AC）上的脱附行为进行了研究。结果表明,吸附主要发生在粗微孔（0.7~2...低挥发性有机酸不仅自身污染环境而且显著促进颗粒污染物形成,对其吸脱附性能的研究有助于这类物质的控制。采用程序升温脱附（TPD）技术对乙二酸、苯甲酸在活性炭（AC）上的脱附行为进行了研究。结果表明,吸附主要发生在粗微孔（0.7~2 nm）、细微孔（〈0.7 nm）中,对应TPD曲线中的吸附位Ⅰ、Ⅱ。粗微孔对乙二酸、苯甲酸的脱附活化能为101.63、112.43 k J·mol^-1,吸附量均大于总吸附量的91%。细微孔对乙二酸、苯甲酸的脱附活化能为118.01、130.87 k J·mol^-1,吸附量均小于总吸附量的9%。细微孔吸附强度高于粗微孔,但吸附量远低于粗微孔,因为细微孔对吸附质的迁移阻力较大,仅少量吸附质能进入细微孔中。苯甲酸在迁移中受到阻力较乙二酸大,在细微孔中吸附量更小,表现为分子筛分作用。展开更多
To improve the understanding of the transport mechanism in shale gas reservoirs and build a theoretical basic for further researches on productivity evaluation and efficient exploitation, various gas transport mechani...To improve the understanding of the transport mechanism in shale gas reservoirs and build a theoretical basic for further researches on productivity evaluation and efficient exploitation, various gas transport mechanisms within a shale gas reservoir exploited by a horizontal well were thoroughly investigated, which took diffusion, adsorption/desorption and Darcy flow into account. The characteristics of diffusion in nano-scale pores in matrix and desorption on the matrix surface were both considered in the improved differential equations for seepage flow. By integrating the Langmuir isotherm desorption items into the new total dimensionless compression coefficient in matrix, the transport function and seepage flow could be formalized, simplified and consistent with the conventional form of diffusion equation. Furthermore, by utilizing the Laplace change and Sethfest inversion changes, the calculated results were obtained and further discussions indicated that transfer mechanisms were influenced by diffusion, adsorption/desorption. The research shows that when the matrix permeability is closed to magnitude of 10^-9D, the matrix flow only occurs near the surfacial matrix; as to the actual production, the central matrix blocks are barely involved in the production; the closer to the surface of matrix, the lower the pressure is and the more obvious the diffusion effect is; the behavior of adsorption/desorption can increase the matrix flow rate significantly and slow down the pressure of horizontal well obviously.展开更多
文摘低挥发性有机酸不仅自身污染环境而且显著促进颗粒污染物形成,对其吸脱附性能的研究有助于这类物质的控制。采用程序升温脱附（TPD）技术对乙二酸、苯甲酸在活性炭（AC）上的脱附行为进行了研究。结果表明,吸附主要发生在粗微孔（0.7~2 nm）、细微孔（〈0.7 nm）中,对应TPD曲线中的吸附位Ⅰ、Ⅱ。粗微孔对乙二酸、苯甲酸的脱附活化能为101.63、112.43 k J·mol^-1,吸附量均大于总吸附量的91%。细微孔对乙二酸、苯甲酸的脱附活化能为118.01、130.87 k J·mol^-1,吸附量均小于总吸附量的9%。细微孔吸附强度高于粗微孔,但吸附量远低于粗微孔,因为细微孔对吸附质的迁移阻力较大,仅少量吸附质能进入细微孔中。苯甲酸在迁移中受到阻力较乙二酸大,在细微孔中吸附量更小,表现为分子筛分作用。
基金Foundation item： Project（PLN1129）supported by Opening Fund of State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation （Southwest Petroleum University）, China
文摘To improve the understanding of the transport mechanism in shale gas reservoirs and build a theoretical basic for further researches on productivity evaluation and efficient exploitation, various gas transport mechanisms within a shale gas reservoir exploited by a horizontal well were thoroughly investigated, which took diffusion, adsorption/desorption and Darcy flow into account. The characteristics of diffusion in nano-scale pores in matrix and desorption on the matrix surface were both considered in the improved differential equations for seepage flow. By integrating the Langmuir isotherm desorption items into the new total dimensionless compression coefficient in matrix, the transport function and seepage flow could be formalized, simplified and consistent with the conventional form of diffusion equation. Furthermore, by utilizing the Laplace change and Sethfest inversion changes, the calculated results were obtained and further discussions indicated that transfer mechanisms were influenced by diffusion, adsorption/desorption. The research shows that when the matrix permeability is closed to magnitude of 10^-9D, the matrix flow only occurs near the surfacial matrix; as to the actual production, the central matrix blocks are barely involved in the production; the closer to the surface of matrix, the lower the pressure is and the more obvious the diffusion effect is; the behavior of adsorption/desorption can increase the matrix flow rate significantly and slow down the pressure of horizontal well obviously.
