Pressure Drop in Pipelines

Pressure drop equation(Sinnott R. K. , Coulson & Richardson’s Chemical Engineering, Vol 6)

Pipe roughness(Sinnott R. K. , Coulson &

Richardson’s Chemical Engineering, Vol 6)

Friction Factor(Sinnott R. K. , Coulson & Richardson’s Chemical Engineering, Vol 6)

Pressure losses due to fittings/valves etc

• 1. Calculated as velocity heads• u2 / 2g

2. Calculated as equivalent pipe diameters

Pressure loss in fittings and valves(Sinnott R. K. , Coulson & Richardson’s Chemical Engineering, Vol 6)

Example(Sinnott R. K. , Coulson & Richardson’s Chemical Engineering, Vol 6)

Power requirements for pumping(Sinnott R. K. , Coulson & Richardson’s Chemical Engineering, Vol 6)

Energy for pumping(Sinnott R. K. , Coulson & Richardson’s Chemical Engineering, Vol 6)

Example(Sinnott R. K. , Coulson & Richardson’s Chemical Engineering, Vol 6)

Factors in pipe size selection

• Pressure – pipe thickness• Typical velocities and pressure

drops• Economic pipe diameter

• Capital costs• Operating costs

Optimum pipe size - turbulent flow(Sinnott R. K. , Coulson & Richardson’s Chemical Engineering, Vol 6)

Example 5.6(Sinnott R. K. , Coulson & Richardson’s Chemical Engineering, Vol 6)

• Estimate the optimun pipe diameter for a water flow rate of 10 kg/s at 20 C. Carbon Steel pipe will be used. Density of water is 1000 kg/m3.

Example 5.7(Sinnott R. K. , Coulson & Richardson’s Chemical Engineering, Vol 6)

• Estimate the optimum pipe diameter for a flow of HCl of 7000 kg/h at 5 bar, 15 C, stainless steel pipe. The MW of HCl is 36.5 and the molar volume is 22.4 m3/kmol at 1 bar and 0 C.

The end

Homework – Do example 5.8Next week: Separator Design