Boiler Blowdown Rate
A blowdown of the boiler is a routine operation necessary due to the increased concentration of Total Dissolved Solids - TDS - in the boiler water when producing steam.
The blow down rate of a boiler depends on
- steam consumption (steam used in the process and not returned as condensate to the boiler)
- concentration of impurities in the feed water
- maximum allowable TDS in the boiler
The blowdown rate can be calculated as
qBD= qS fc / (bc - fc) (1)
where
qBD = blowdown rate (kg/h)
qS = steam consumption (kg/h)
fc = Total Dissolved Solids - TDS - in the feed water (ppm)
bc = maximum allowable Total Dissolved Solids - TDS - in the boiler water (ppm)
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