Numerical

Economiser Heat Recovery

Feedwater flow is 20,000 kg/h and temperature rises by 45°C. Take specific heat as 4.187 kJ/kg·K. Calculate heat recovered.

Problem

Feedwater flow is 20,000 kg/h and temperature rises by 45°C. Take specific heat as 4.187 kJ/kg·K. Calculate heat recovered.

Given Data

Write all quantities in consistent SI units before substitution.

Formula and Solution

Q = m cp ΔT = 20,000 × 4.187 × 45 = 3,768,300 kJ/h = 1,046.75 kW.

Engineering Check

Check units, magnitude and physical meaning. State any simplifying assumptions and avoid mixing mass flow per hour with energy per second.

Practice Variation

Repeat the problem after changing one input by 10% and explain how the answer responds.