Sales Gas Pipeline Part II

Ref.1: Ikoku, Natural Gas Production Engineering, John Wiley & Sons, 1984, Chapter 7.Ref.2: Menon, Gas Pipeline Hydraulic, Taylor & Francis, 2005, Chapter 3.

1

Single Phase Gas Flow Series Pipeline with Elevation Change

P2

P1

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P5

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6

Single Phase Gas Flow Parallel Pipeline with Elevation Change

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7

Single Phase Gas Flow Parallel Pipeline with Elevation Change

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8

Single Phase Gas Flow Looped Pipeline with Elevation Change

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sc 9

Single Phase Gas Flow Looped Pipeline For Increasing Capacity

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110

Single Phase Gas Flow Looped Pipeline For Increasing Capacity

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11

Single Phase Gas Flow Optimum Diameter of Looped Pipeline

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)( :cost Installed 5.15.1CAfBbaseBBBbaseB LLxdCCLdCC

Assume that the cost of a pipe with one inch diameter and one foot length is Cbase

y)graphicall problem thisSolve(0dd:

B

BB d

CdForOptimum

Single Phase Gas Flow Example 1: Description

P2

P1

P3

P4

P5

For the above pipeline, calculate the exit pressure of each segments (P2, P3, P4, P5) based on Weymouth equation and Hysys software.

Feed specifications: T1=50 oF, P1=1000 psia, qsc=200 MMscfd, C1=90%, C2=10% (mole)

Pipeline specifications:L1=20 km, ΔZ1=2000 m, L2=30 km, ΔZ2=-500, L3=15 km, ΔZ3=600, L4=50 km, ΔZ4=-800, d1= d2= d3= d4= 20 in, T5=35 oF, E=0.95(in Weymouth) 13

Single Phase Gas Flow Example 1: Solution

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15

Single Phase Gas Flow Example 2: Description

P2P1

LA , dA

LB , dB

LC , dC Px

An old pipeline has the following specification:

Feed specifications: T1=50 oC, P1=1000 psia, qold =1500 MMscfd, C1=90%, C2=10% (mole)

Pipeline specifications:LA+LC =100 km, ΔZ=0, dA= dC= 42 in, T2=42 oC, E=0.95(in Weymouth)

a)Calculate the outlet pressure (P2)

b)The pipeline capacity is increased by 25% (qnew=1875 MMscfd). Calculate the optimum length and diameter of the looped pipeline.


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)3.68(1.69691.0 kmkmLx Bf

Documents

Sales Gas Pipeline Part II