Method and system of recovering the heat wasted from the steam boilers continuous blow down to preheat the boiler combustion air

Abstract

Heat from continuous blow down from a steam boiler is used to preheat boiler combustion air. Blow down from the steam boiler is fed through a flash tank and a 3-way valve to a liquid heat exchanger to heat a circulating liquid. The hot circulating liquid is fed to a preheat coil to heat combustion air for a steam boiler. A 3-way valve located between the flash tank and heat exchanger controls the flow of blow down to the heat exchanger. A temperature sensor which monitors the temperature of the circulating liquid controls the 3-way valve and a circulating pump moves the liquid around a closed loop. Motorized or variable frequency drive damper control the flow of air to the preheat coil and to the combustion air blower of the steam boiler.

Dependencies are inferred from the claim text.