Lower order spatial moments for colloidal transport in a fracture-matrix coupled system

Abstract

This paper presents an analysis of the lower order spatial moments of colloidal transport in a coupled fracture-matrix system. For this purpose, colloidal transport is numerically modeled to obtain the spatial distribution of concentration profiles along the fracture. Implicit finite-difference numerical technique has been adopted to obtain the colloidal concentration in the fracture. Subsequently, the first and second spatial moments are evaluated using the colloidal concentration. The results suggest that effective velocity of the colloid is retarded by increment in rock matrix porosity, matrix diffusion coefficient, filtration coefficient, reduction of half-fracture aperture, initial colloid velocity, and remobilization coefficient. Significant mixing of colloids occurs in the fracture due to low-fracture aperture, initial colloid velocity, and filtration coefficient.

Keywords:

• colloid transport
• spatial moments
• numerical modeling
• fracture
• filtration coefficient
• remobilization coefficient