Formula & worked example
Q=ṁ·cp·(Thot−Tcold)·effectiveness.
1,000 kg/h blowdown cooled by 70°C at 70% recovery yields about 57 kW recoverable heat using cp≈4.186 kJ/kg-K.
Plant engineering calculator · Updated Sep 17, 2026
Boiler Blowdown Heat Recovery Calculator — Recoverable kW & Annual Savings
Estimate recoverable heat from continuous boiler blowdown using mass flow, hot blowdown temperature, return temperature and recovery effectiveness. Returns thermal kW, annual MWh and annual value.
Inputs
Live result
Raw sensible heat 81.39444 kW
Recoverable heat 56.97611 kW
Annual recovered heat 455.8089 MWh
Annual indicated value 22,790.44
Assumptions & limits
- Treats blowdown as liquid water with constant specific heat for screening.
- Flash-steam recovery and exchanger pinch/approach constraints should be evaluated separately.
Frequently asked questions
What does this Boiler Blowdown Heat Recovery Calculator calculate?
Estimate recoverable heat from continuous boiler blowdown using mass flow, hot blowdown temperature, return temperature and recovery effectiveness. Returns thermal kW, annual MWh and annual value.
Can I use the result for final equipment selection?
Use it for screening, benchmarking and option comparison. Final selection should use measured conditions, manufacturer performance data and applicable engineering standards.
Why are assumptions shown beside the calculation?
Plant calculations change materially with pressure basis, reference conditions, efficiencies and operating profile. Explicit assumptions make the result auditable instead of hiding those choices.