1. Combined Cycle Plant Applications
FrothFlush™ Condensate and Feedwater
Results:
•Targets
SigmaClean™ HRSG Watersides •Steam Chemistry
•Water Cycle Chemistry
•Stabile Operation
Superheaters/Reheaters/MS piping,
SigmaBlow™ Condenser

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3. Why FrothFlush TM?
• Very high Reynolds numbers and complete turbulence using
small quantities of water return the fastest, highest quality
and most consistent flushing of pipe circuits
• Cleaning to this level prevents contaminates from entering
the steam generation equipment.
• Improves water chemistry in the HRSG which in turn
improves the ability to achieve steam purity.
• Current cleaning requirements result in minimal feedwater
and condensate suction strainer fouling.

4. Froth Former Setup

5. FrothFlush™
6 inch pipe, 1,000 feet in length
40 feet per second
“Froth” (compressible) Air / Water “slug”
The FrothFlush™ process utilizes short two phase (air/water) frothed slugs
displaced at velocities of 15 20 meters/sec generating Reynolds numbers of
4 5 million to remove both particulate and non particulate contamination
from the metal surfaces.

6. FrothFlush™
Full Turbulence
Effectiveness of FrothFlush™ is due to generation of full turbulence that
scrubs particles and salts from pipe & tube surfaces

7. Improved
Cleanliness
• The FrothFlush™ effectiveness in removal of particulate contamination is
monitored by means of Millipore filters. Samples of the flush effluent water
are taken and filters using fine Millipore filters.
• Millipore filters are so fine that the water sample will not flow through the filter
without the aid of a vacuum to draw the sample water through the filter.
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• The effectiveness of the FrothFlush™ process in removal of salts from the
metal surfaces is monitored by measurement of the conductivity of the
effluent flush water.
• VGB Guideline for acceptable solids in flush water is < 5 mg/l.
FrothFlush™ will typically achieve cleanliness of < 0.05 mg/l.
• The VGB Guideline for acceptable flush water conductivity is < 1,000 S/cm.
The FrothFlush™ process typically achieves flush water effluent < 50 S/cm.
VGB(ISO-3166-1, British Virgin Islands)

8. Typical
FrothFlush™
Results
First FrothFlush™ 11th Froth FrothFlush™ Final Effluent on
20th FrothFlush™
The above sequence of photographs show the typical
results of a FrothFlush™ of a piping system

9. Millipore®
0.45 Micron Patch Test
First FrothFlush™ (500ML) 11th FrothFlush™ (500ml) Final Acceptable at 20th Pass
600 S/cm 60 S/cm FrothFlush™ (500ml)
15 S/cm
System cleanliness far exceeds criteria specified in VGB
BES&T Millipore™ Test
Apparatus Guideline and all other water flush methods.

10. FrothFlush™
Preheat & Economizer
Coil Flushing
• Contamination is proportional to system metal surface area.
• Contamination is proportional to amount fabrication to build a HRSG coils.
Cutting, grinding, welding and PWHT generates more contamination.
• Piping typically contributes less contamination than HRSG coils to the
steam cycle as piping has less metal surface and less fabrication.
• The FrothFlush™ process effectively flushes contamination from HRSG
preheat and economizer coil sections at high velocity and high turbulence.
• Effective removal of particulate and non-particulate contamination prior to
gas turbine first fire minimizes fouling of BFW pump and attemperator
strainers and sensitive control valve trim.
• Removal of imbedded salts from metal surfaces of the pre-boiler piping and
coils reduces the tine required to achieve steam cycle purity.