Blowdown vessels
Overview
Boiler blowdown vessels are used to receive high-temperature water discharged from bottom blowdown or TDS blowdown systems before it is released to drain. They help separate flash steam from the water stream and create a safer, more controlled blowdown discharge arrangement for the boiler house. This is especially important where direct discharge of hot blowdown water would create risk for personnel, nearby equipment or site drainage infrastructure. Spirax Sarco blowdown vessels are designed, manufactured and inspected to PD 5500 and are available with full manufacturing quality documentation where project traceability matters. They are commonly selected alongside blowdown valves, vent heads and heat recovery equipment when users want a complete boiler blowdown package rather than an isolated vessel.
Related boiler blowdown routes
Blowdown vessels are usually chosen within a broader discharge and recovery arrangement. If the upstream duty still depends on valve selection and sludge removal strategy, compare bottom blowdown systems and TDS blowdown controls.
Where the next step is reclaiming energy from the blowdown stream rather than only cooling it for discharge, continue into boiler blowdown heat recovery systems and the wider boiler controls.
Continue your boiler blowdown selection
A blowdown vessel is usually one part of a wider boiler blowdown arrangement. The next decision often sits upstream on control, or downstream on venting and heat recovery.
Choose the upstream blowdown duty
Go to bottom blowdown systems when you are choosing the valve and control arrangement upstream of the vessel and need a more complete blowdown package.
Complete the blowdown discharge arrangement
Use vent heads when the discharge arrangement also needs low-velocity venting and condensate separation at the end of the blowdown or vent line.
Recover energy from boiler blowdown
Review boiler blowdown heat recovery when the next priority is reclaiming flash steam and hot water value rather than discharging that energy to drain.