ProcessPI - Pipeline Examples

This document contains worked examples using the ProcessPI pipeline engine and network module.

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Example 1: Chlorine Gas Pipeline

Estimate the optimum pipe diameter for a flow of dry chlorine gas of 10 000 kg/h at 6 atm and 20°C through carbon steel pipe.

from processpi.components import *
from processpi.units import *
from processpi.pipelines.engine import PipelineEngine

# Define fluid and mass flow
fluid = Chlorine(temperature=Temperature(20, "C"), pressure=Pressure(6, "atm"))
mass_flow = MassFlowRate(10000, "kg/h")

print(fluid.density())

# Create engine without an explicit network
model = PipelineEngine()
model.fit(
    fluid=fluid,
    mass_flow=mass_flow
)
results = model.run()  # auto diameter sizing
results.summary()
results.detailed_summary()

Output

17.685884 kg/m3
✅ Found optimal diameter based on recommended velocity.
   Selected Diameter: 8.0 in 
   Calculated Pressure Drop: 15.43 Pa
⚠️ Warning: Final velocity 4.87 m/s outside recommended range (5.00-10.00 m/s) for Chlorine.

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Example 2: CO₂ Transfer Pipeline

Carbon dioxide is to be conveyed from the top of the stripper of ammonia plant to urea plant.

from processpi.units import *
from processpi.components import *
from processpi.pipelines.engine import PipelineEngine
from processpi.pipelines.pipes import Pipe
from processpi.pipelines.fittings import Fitting

fluid = Carbondioxide(temperature=Temperature(60, "C"))
print(fluid.density(), fluid.viscosity().to("cP"))

mass_flow = MassFlowRate(1000, "t/day")
pipe = Pipe(name="Main Pipe", length=Length(800, "m"), material="CS")
elbow = Fitting(fitting_type="standard_elbow_90_deg", quantity=8)
valve = Fitting(fitting_type="gate_valve", quantity=1)
nozzle = Fitting(fitting_type="exit", quantity=1)

model = PipelineEngine()
model.fit(
    fluid=fluid,
    mass_flow=mass_flow,
    pipe=pipe,
    fittings=[elbow, valve, nozzle],
    available_dp=Pressure(24, "kPa")
)
results = model.run()
model.summary()
results.detailed_summary()

Output

1.609882 kg/m3 0.019523 cP (dynamic)
✅ Found optimal diameter for available pressure drop.
   Selected Diameter: 22.0 in (0.559 m)
   Calculated Pressure Drop: 18414.26 Pa (allowed: 24000.00 Pa)
⚠️ Warning: Final velocity 31.41 m/s outside recommended range (8.00-15.00 m/s) for Carbon Dioxide.

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Example 3: Carbon Monoxide Pipeline

from processpi.units import *
from processpi.components import *
from processpi.pipelines.engine import PipelineEngine
from processpi.pipelines.pipes import Pipe
from processpi.pipelines.fittings import Fitting

fluid = CarbonMonoxide(temperature=Temperature(50, "C"))

mass_flow = MassFlowRate(1500, "kg/h")
pipe = Pipe(name="Main Pipe", length=Length(4, "km"), material="CS")
valves = Fitting(fitting_type="gate_valve", quantity=2)
elbows_45 = Fitting(fitting_type="standard_elbow_45_deg", quantity=3)
elbows_90 = Fitting(fitting_type="standard_elbow_90_deg", quantity=6)

model = PipelineEngine()
model.fit(
    fluid=fluid,
    mass_flow=mass_flow,
    pipe=pipe,
    fittings=[elbows_45, elbows_90, valves],
    available_dp=Pressure(50, "kPa"),
)
results = model.run()
model.summary()
print(results.total_pressure_drop.to("atm"))
results.detailed_summary()

Output

✅ Found optimal diameter for available pressure drop.
   Selected Diameter: 8.0 in (0.203 m)
   Calculated Pressure Drop: 28658.34 Pa (allowed: 50000.00 Pa)

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Example 4: Water Transfer (Steel vs Concrete)

from processpi.components import *
from processpi.units import *
from processpi.pipelines.engine import PipelineEngine
from processpi.pipelines.pipes import Pipe

fluid = Water(temperature=Temperature(40, "C"))
length = Length(3200, "m")
pipe = Pipe(name="Main Water Pipe", length=length, material="Concrete")
pipe2 = Pipe(name="Main Water Pipe", length=length, material="CS")
allowable_dp = Pressure(0.58, "atm")
flow_rate = MassFlowRate(100000, "kg/h")

model = PipelineEngine()
model.fit(fluid=fluid, pipe=pipe, mass_flow=flow_rate, available_dp=allowable_dp)

model2 = PipelineEngine()
model2.fit(fluid=fluid, pipe=pipe2, mass_flow=flow_rate, available_dp=allowable_dp)

results = model.run()
results2 = model2.run()

model.summary()
results.detailed_summary()
model2.summary()
results2.detailed_summary()

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Example 5: Organic Liquid with Valves

from processpi.units import *
from processpi.components import *
from processpi.pipelines.engine import PipelineEngine
from processpi.pipelines.pipes import Pipe
from processpi.pipelines.fittings import Fitting

fluid = OrganicLiquid(density=Density(930, "kg/m3"), viscosity=Viscosity(0.91, "cP"))
mass_flow = MassFlowRate(5000, "kg/h")

pipe = Pipe(name="Main Organic Liquid Pipe", length=Length(50, "m"))
elbow = Fitting(fitting_type="standard_elbow_90_deg", quantity=6)
tees = Fitting(fitting_type="standard_tee_through_flow", quantity=2)
gate_valves = Fitting(fitting_type="gate_valve", quantity=2)
globe_valves = Fitting(fitting_type="globe_valve", quantity=2)
orifice = Fitting(fitting_type="sudden_contraction", quantity=1)

model = PipelineEngine()
model.fit(
    fluid=fluid,
    mass_flow=mass_flow,
    pipe=pipe,
    fittings=[elbow, tees, gate_valves, globe_valves, orifice],
)
results = model.run()
model.summary()
results.detailed_summary()

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Example 6: Complex Network (Chilled Water Loop)

from processpi.pipelines.engine import PipelineEngine
from processpi.pipelines.pipes import Pipe
from processpi.pipelines.network import PipelineNetwork
from processpi.pipelines.pumps import Pump
from processpi.pipelines.vessel import Vessel
from processpi.pipelines.equipment import Equipment
from processpi.units import *
from processpi.components import Water

# Build network
net = PipelineNetwork("Chilled Water Loop")

# Nodes
net.add_node("Tank", elevation=0)
net.add_node("Pump_In", elevation=0)
net.add_node("Pump_Out", elevation=1)
net.add_node("Main_In", elevation=1)
net.add_node("Main_Out", elevation=1)
net.add_node("Return_Tank", elevation=0)

pump = Pump("Pump1", pump_type="Centrifugal", inlet_pressure=Pressure(101325, "Pa"), outlet_pressure=Pressure(201325, "Pa"))
vessel = Vessel("ExpansionTank")
chiller = Equipment("Chiller", pressure_drop=0.2)

# Tank → Pump
net.add_edge(Pipe("TankPipe", length=5), "Tank", "Pump_In")
net.add_edge(pump, "Pump_In", "Pump_Out")

# Pump → Main header
net.add_edge(Pipe("MainPipe", length=15), "Pump_Out", "Main_In")
net.add_edge(Pipe("MainPipe_Out", length=5), "Main_In", "Main_Out")

# Returns → Tank
net.add_edge(vessel, "Main_Out", "Return_Tank")
net.add_edge(chiller, "Return_Tank", "Pump_In")

fluid = Water(temperature=Temperature(10, "C"), pressure=Pressure(101325, "Pa"))
flow_rate = VolumetricFlowRate(300, "m3/h")

model = PipelineEngine()
model.fit(fluid=fluid, flow_rate=flow_rate, network=net)
results = model.run()

results.summary()
results.detailed_summary()

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