Investigation of feasibility and potential mechanisms for the bioregeneration of perchlorate laden gel-type anion exchange resin

摘要

The feasibility and potential mechanisms for the bioregeneration of perchlorate laden gel-type anion exchange resin were investigated in this study. Bioregeneration is a sustainable process when compared to one time use of resin and disposal by incineration. Batch and bench-scale bioregeneration experiments were performed to evaluate the feasibility of the process and to gain insight into potential mechanisms that control gel-type resin bioregeneration. The results of the bioregeneration tests suggested that the initial phase of the bioregeneration process is controlled by kinetics, while the later phase is controlled by diffusion. Higher perchlorate load in the resin had a positive effect on perchlorate degradation rates, while varying microbial concentration did not have a significant effect on perchlorate degradation in gel-type resin. The presence of nitrate suppressed perchlorate degradation initially, but once all nitrate was denitrified, perchlorate degradation took place. Feasibility study showed that direct bioregeneration of gel-type resin was effective in a fluidized-bed reactor, and the resin could be reused and repeatedly regenerated with this method.