GE P&W GenGard Corrosion Treatment Programs - Manual (Page 2)

Page 2 Fact Sheet
tection. HRA is halogen stable and capable of
maintaining effective corrosion inhibition even in
the presence of chlorine and bromine-based bio-
cides. Conventional azole inhibitors, such as tolyl-
triazole and benzotriazole, are readily halogenated
in the cooling water, preventing the establishment
and repair of a protective film on the metal surface.
HRA maintains its activity both in the water and on
the metal surface, ensuring continuous protection
for copper alloys. HRA also reduces copper levels in
the cooling water, minimizing copper discharge and
effectively controlling destructive galvanic pitting
on steel surfaces.
Typical Applications
The GenGard GN7000 series of products are
designed for cooling systems operating in the near-
neutral pH 6.8 - 7.8 range. They utilize high levels of
inorganic phosphate to promote the formation of a
thin, protective iron oxide film on steel surfaces.
This protective oxide film is extremely tenacious
and does not interfere with heat transfer. STP pro-
vides the necessary calcium phosphate control to
maintain system cleanliness and uninterrupted op-
eration. (See Figure 2.)
The GenGard GN8000 series of products are
designed for waters in the less corrosive alkaline
range above pH 7.8. GN8000 products utilize AEC as
the basic component to allow operation at highly
alkaline conditions without concern for scale forma-
tion.
For More Information
For more information on the GenGard Technology,
please contact a GE account representative or visit
us on the web at www.ge.com/water.
Figure 2: Comparison of Halogen Stable vs. Conventional Treatment, neutral pH,
phosphate program, continuous chlorination (0.5 - 1.0 ppm free Cl2)
8 ppm AA/AMPS /BZT
LCS - 1.4 mpy
ADM - 0.6 mpy
2 ppm STP/HRA
LCS <0.5 mpy
ADM <0.2 mpy