Steam Coil Calculation [PDF]

Zitiervorschau

Calculate the average steam mass flowrate during start-up - Pressure = 3.2 bar g Note: Steam pressure onto the control valve - Steam Temperature = 135 °C = 408 K - Minimum Steam Pressure = 1.856 bar g Note: Critical pressure drop (CPD) will occur across the con - Hfg = 2201 Kj/Kg Note: Enthalphy of Evaporation at 1,856 bar g from table - Q Required = 433580.6 kJ/h Note: Heat transfer requirement To heat Tank (From Heat B = 120.4391 kW - Average Steam Flow rate = 0.05 kg/s 196.99 kg/h Calculate the heat transfer area required - QQ = 433580.6 kJ/h = 120.4391 kW - U = 650 W/m² °C - Ts = 117.69 °C - Tf = 90 °C - T0 = 60 °C - Tm = 75 °C - ΔTm = 42.69 °C - Coil Surface Area Required = 4.34 m² - Coil Surface Area Recommen = 4.77 m²

Note: Heat transfer requirement To heat Tank (From Heat B Note: Heat Transfer Coef. From Steam/coil/Liquid Note: Steam Coil Temperature at 1,856 bar g from table Note: Final Temperatur Wanted Note: Initial Temperature Note: Mean Liquid Temperature Note: Delta Temperature

The maximum steam mass flowrate with the recommended heat transfer area - QQ = 433580.6 kJ/h Note: Heat transfer requirement To heat Tank (From Heat B = 120.4 kW - U = 650 W/m² °C Note: Heat Transfer Coef. From Steam/coil/Liquid - Ts = 117.69 °C Note: Steam Coil Temperature at 90 °C from table - Tf = 90 °C Note: Final Temperatur Wanted - T0 = 60 °C Note: Initial Temperature - ΔT = 57.69 °C Note: Delta Temperature - QQ coil = 179.04 kW = 644526.9 kJ/h - rhs = 1063.15 kg/h Note: Steam flowrate to deliver 519 kW Determine coil length - O/D Pipe - Cross Section Area of Pipe - Pipe Length

= 2 Inch = 0.189 m²/m = 25.26239 m

Note= From Table

Sumber: https://beta.spiraxsarco.com/learn-about-steam/steam-engineering-principles-and-heat-transfer/heating-with-coils-a

control valve

PD) will occur across the control valve during start-up, therefore the minimum steam pressure in the heating coil should be taken as 58% of n at 1,856 bar g from table nt To heat Tank (From Heat Balance)

nt To heat Tank (From Heat Balance)

Steam/coil/Liquid at 1,856 bar g from table

nt To heat Tank (From Heat Balance)

Steam/coil/Liquid at 90 °C from table

transfer/heating-with-coils-and-jackets

ng coil should be taken as 58% of upstream absolute pressure. An explanation of this is given in Block 5.

1.5 1.856 2

3 3.2 3.5

111.378 117.6885 120.241

133.555 135.6894 138.891