关键词: 颗粒, 多孔介质, 吸附, 解吸, 解析解

Abstract: The governing equation for particle accelerated transport is developed with considering adsorption-desorption effects, and then analytical solutions for particle instantaneous injection and periodic injection with point and surface sources are obtained using Laplace and Fourier transforms. Experiments on the particle instantaneous injection for point source are carried out. Comparisons between the experimental and theoretical results show that the proposed procedure can simulate the particle transport reasonably well. In addition, the transport parameters are analyzed for the case of particle instantaneous injection for the point source. It is shown that the peak concentration of particles decreases with the increase of adsorption coefficient. The effect of desorption coefficient on the curve part on the right of peak concentration is trivial; however, for the curve part on the left of the peak concentration, desorption coefficient affects both the particle concentration and the particle transport time. Furthermore, the shapes of the concentration contours in the x-y plane are approximately elliptic, and the range of the concentration contours increases with the increase of desorption coefficient. The contour gradients at upper and lower sides of the peak concentration decrease with the increase of dispersion coefficient. The study results provide a theoretical basis for various engineering items such as the underground pollutant treatment, exploration of groundwater, nuclear waste disposal and land filling of municipal solid wastes, and so on.

Key words: particle, porous media, adsorption, desorption, analytical solution