Bio – flushing

The prototype simulates the injection / extraction process of in-situ bio-flushing technology, using vertical wells and horizontal drains. BIO-flushing uses a flexible system, which must allow the inoculation of biological solutions, chemical flushing solutions, and must do so effectively in both saturated and unsaturated soil.

The effectiveness of the technology lies in its ability to establish a filtration flow that engages the entire volume being treated. In the prototype, two hydraulic circulation modes have been developed: the Jetting mode and the Dispersion mode. This was possible thanks to the design of innovative injection devices, in which an electrically controlled valve isolates the injector sections assigned to the Jetting and Dispersion modes.

This prototype represents a full-scale volume of 5 m3 of soil where two lithological layers have been reconstructed, the upper one made of anthropic backfill and the lower one with a more abundant natural loamy-clay component (less permeable).

In the prototype, the discontinuity between the two lithologies almost coincides with the level of the aquifer. The physical prototype was used to calibrate the corresponding mathematical model, programmed in MODFLOW-FEFLOW Software. This made it possible to determine, within the soil volume, the trend of all the relevant parameters for the study of the phenomenon (flow rates, trajectory of the water particles, hydraulic load and pressure).