PB2
Pilot testing gaseous substrate dosing using microspargers requires experience
and feeling for the underground situation.
Here propane is injected into the groundwater using 10 micron
spargefilters (white tube). The
resulting propane bubbles have such a small internal radius that they do not
easy coalesce. Due to the micro
bubbles filled with propane the water around these spargers turns grey.
After a period of micro-sparging the grey water is pushed rapidly into
the formation using low pressure nitrogen (black pipe).
The timing when to switch between substrate micro-sparging and nitrogen
sparging can be found in the amount of micro-bubbles in the main injection well
: a measure of the reduction in hydraulic head measured by a sensitive pressure
sensor (white cable).
