Numerical modeling of cosolvent flooding of DNAPL-contaminated homogeneous glass bead columns

摘要

An existing compositional multiphase flow simulator (UTCHEM) was adapted to represent the phase behavior of ternary and quaternary cosolvent/DNAPL systems. Simulator predictions were compared to results from laboratory experiments with homogeneous glass bead columns. Mixing due to displacement instabilities appeared to control the displacement behavior during the experiments. This could be matched numerically by postulating a large dispersivity in one-dimensional or by including heterogeneities on a small scale in three-dimensional simulations. The high apparent dispersivity reduced the effectiveness of cosolvent floods. Potential for displacement instability should be taken into account during design of flushing operations.