Steam shoot Blower
Differential Pressure Flow Sensors
Verabar flow sensors are the measurement of choice in
many fluidized bed coal combustion power plant applications.
Fluidized beds suspend solid fuels on upward jets of air
during the combustion process. The result is a turbulent
mixing of gas and solids. The turbulent action, much like
a bubbling fluid, provides more effective chemical reactions,
heat transfer and lowers emissions.
Verabar applications include Air (primary, secondary, combustion,
undergrate, seal, FGD’s and OFA), Water (condenser, boiler
feed water and cooling) and Steam (LP, IP, HP, SBF).
High Pressure Steam: Soot Blower
Flow
Industry: Power
2. The Verabar produced accurate readings over the entire
10:1 flow range.
3. Multivariable transmitters were incorporated to output
a dynamically compensated flow rate.
Application:
Alabama Power operates a coal fired, fluidized bed power
plant in Burks, Alabama. They requested assistance in solving
a problem in the measurement of Soot Blower Flow (SBF) where
superheated steam is used to remove the combustion residue
for disposal. The Flowing Conditions are: 4” pipe - 50,000
(max.), 5,000 (min.) lbs/hr, 609 psig @ 700°F.
Problems:
Initially, two Vortex Meters were installed, proving
to be unreliable:
1. First the vortex meters became inoperable during start-up
due to water hammer from residual condensate.
2. After repair, they were inaccurate below 50% of flow
and could not measure the minimum flow rate.
3. Additionally, the vortex meter could not output a temperature
and pressure compensated flow rate.
Solution:
Veris designed two special 600# flanged spool sections
with integral V510 flanged Verabar flow sensors and separate
flanged RTD’s in a Thermowell (Photo 1). The spool piece
had to fit the existing dimensions of the Vortex meters.
The DP at max flow was 175.288” H20 (50,000 lbs/hr). At
minimum flow (5000 lbs/hr), the DP was 1.75” H20. This represents
a 100:1 turndown in DP and a 10:1 turndown in flow.
Results:
Alabama Power reported complete satisfaction with the
performance of the Verabar spool sections (Photo 2).
1. Problems associated with water hammer from residual condensate
during start-up were eliminated.
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