Heat recovery systems
Overview
Heat recovery from boiler blowdown captures energy that would otherwise be wasted when high-temperature blowdown water flashes to steam at lower pressure. In a typical arrangement, flash steam is separated in a flash vessel and returned to the feedtank, while the remaining hot water can be used through a heat exchanger to warm incoming make-up water. This helps reduce make-up water demand, water treatment cost and boiler fuel use while also lowering blowdown discharge temperature. Boiler blowdown heat recovery is especially relevant where automatic TDS control creates a consistent blowdown stream and the site wants to reclaim more of the treated water and heat value already paid for. Spirax Sarco heat recovery systems support boiler house efficiency improvement without relying on generic energy-saving measures detached from the actual blowdown duty. They are typically reviewed when users want to convert boiler blowdown from a necessary loss into a measurable recovery opportunity inside the wider boiler house energy balance.
Related boiler heat-recovery routes
Blowdown heat recovery works best when the blowdown source and feedwater destination are stable. Pair the recovery package with TDS blowdown controls when automatic blowdown creates the upstream stream, and connect the recovered energy into deaerators on the feedwater side.
If the project is still deciding between recovery and safer discharge handling, compare blowdown vessels.
Continue your boiler heat recovery project
Boiler blowdown heat recovery sits between blowdown control and feedwater reuse. The strongest results come when those connected duties are selected together.
Connect heat recovery with feedwater conditioning
Review feedtanks when the recovered flash steam or heated make-up water needs to be integrated into the wider boiler feedwater arrangement.
Stabilise the blowdown source upstream
Use TDS blowdown controls when the heat recovery project also depends on stable, automatic blowdown management upstream of the recovery package.
Compare discharge safety with heat recovery
Go to blowdown vessels when the first requirement is safer handling and cooling of blowdown discharge rather than heat reclamation from that stream.