Boiler water blowdown control system

[cicididi]

A method for controlling a boiler system having a boiler and a feed water assembly arranged and configured to deliver feed water having a known feed water composition to the boiler at a substantially constant feed water rate when activated comprising: determining a target blowdown as a percentage of the feed water rate; setting a blowdown assembly to remove boiler water from the boiler at a substantially fixed blowdown flow rate when activated, the blowdown flow rate being selected to achieve the target blowdown; monitoring a first boiler system parameter.
The present invention provides a method for controlling boiler water concentration in boiler systems that utilize bimodal boiler water pump that have only an ON mode and an OFF mode capable of providing feedwater to the boiler at a substantially constant flow rate in the ON mode. The present method is generally not applicable, however, to boiler systems that utilize boiler feed water pumps that incorporate proportional feedwater flow control valves that regulate the feedwater flow rate within a given range.