Proper Grouting - Bosch Geothermal Heat Pumps Applications Manual

Applications Manual

10.8 Proper Grouting

The "approved" method of grouting a vertical borehole
is called "Tremie" grouting. It is sometimes also referred
to as pressure grouting. Once the vertical loop has been
installed into the borehole, another hose must be run
down to the bottom of the borehole. It is necessary that
the Tremie hose reach the bottom of the borehole before
the grouting process begins. By pumping from the bottom
of the hole up, water in the hole is completely displaced
with high solids, low permeability bentonite grout.
The grout provides a median of heat transfer between
the loop pipe and the earth and protects from surface
contaminants.
Typically, grouting is performed with a rig or trailer-
mounted grout unit (Fig. 66). This includes:
f
Grout/Slurry Mixing Tank
f
Grout/Slurry Pump
f
Tremie Line Hose Reel
f
Flexible HDPE Tremie Pipe
Fig. 66 Trailer mounted grout unit
Courtesy of International Ground Source Heat Pump Association/Oklahoma
State University
Bosch Thermotechnology Corp.
Bosch Geothermal Heat Pumps | 73
Data subject to change