KOYA UNIVERSITY
PETROLEUM ENGINEERING DEPARTMENT
THIRD STAGE
PRODUCTION TECHNOLOGY II , S6
CHAPTER FOUR
OIL AND GAS SEPARATION
@DPTE 2025
Dr. Sarhad Ahmed Farkha
Sarhad.ahmed@koyauniversity.org
PhD Petroleum Engineering – Production Engineering – Koya University – October 2024
MSc Petroleum Engineering- Teesside Uni. United Kingdom October 2013
BSc Petroleum Engineering – Koya University July 2010
Member of Society of Petroleum Engineer (SPE), Onepetro access
Separation Design
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Separators Design
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Separation Design
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Separators Design
General Separator Design Consideration:
Factors Affecting Separation:
The following factors must be determined before separator design:
• Gas and liquid flow rates (minimum, average, and peak)
• Operating and design pressures and temperatures
• Surging or slugging tendencies of the feed streams
• Physical properties of the fluids such as density and compressibility
• Designed degree of separation (e.g., removing 100% of particles greater
than 10 microns)
• Presence of impurities (paraffin, sand, scale, etc.)
• Foaming tendencies of the crude oil
• Corrosive tendencies of the liquids or gas
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Separation Design
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Separators Design
General Separator Design Consideration:
Design Considerations:
The following must be considered in designing a separator vessel:
• The volumes of the dished heads
• The length/diameter (L/D)
• acceptable when it is between about 3/1 and 8/1
• For a vertical separator, the gas flows through the entire cross section of
the upper part of the vessel.
• For a horizontal separator, the interface does not have to be at the
centerline of the vessel.
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Separation Design
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Separators Design
• The basic factors that effect on separators design are:
1. Working pressure
2. Working temperature
3. Fluid component
• Separator design consisting as follows:
1. Calculate gas section capacity.
2. Calculate oil section capacity.
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Separation Design
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A- Vertical Separator Design
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Separation Design
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A- Capacity of vertical Separators:
1. Gas Capacity:
• Suppose there is a liquid drop in the gravity settling section, the liquid drops will
settle at a velocity determined by equation the gravity force (𝑭𝒅 ), on the drop
with the drag force (𝑭𝒖 ) caused by its motion relative to the gas continuous
phase.
𝝅 𝟐
𝒅𝒑 𝒌 𝝆𝒈 𝒖𝟐
(𝟒. 𝟏)
𝟒
𝝅
𝑫𝒐𝒘𝒏𝒂𝒓𝒅 𝒇𝒐𝒓𝒄𝒆 , 𝑭𝒅 = 𝒅𝟑𝒑 (𝝆𝒐 −𝝆𝒈 ) 𝒈
(𝟒. 𝟐)
𝟔
• If 𝑭𝒖 = 𝑭𝒅 ; Then the droplet will remain suspended and gas velocity call suspended
velocity.
𝝅 𝟐
𝝅
𝒅𝒑 𝒌 𝝆𝒈 𝒖𝟐 = 𝒅𝟑𝒑 (𝝆𝒐 −𝝆𝒈 ) 𝒈
(𝟒. 𝟑)
𝟒
𝟔
𝟎.𝟓
𝟐 𝒈 𝒅𝒑 (𝝆𝒐 −𝝆𝒈 )
𝒖=
൘𝟑𝒌 𝝆
(𝟒. 𝟒)
𝒈
𝑼𝒑𝒘𝒂𝒓𝒅 𝒇𝒐𝒓𝒄𝒆 , 𝑭𝒖 =
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Separation Design
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A- Capacity of vertical Separators:
1. Gas Capacity:
• If 𝑑𝑝 , 𝑔 & 𝑘 remain constant, then;
𝟎.𝟓
(𝝆𝒐 −𝝆𝒈 )
൘𝝆
𝒖= 𝒄
𝒈
𝝅 𝟐
𝒒𝒈 =
𝒅 𝒖
𝟒
𝟎.𝟓
𝝅 𝟐 (𝝆𝒐 −𝝆𝒈 )
൘𝝆
𝒒𝒈 =
𝒅 𝒄
𝒈
𝟒
•
(𝟒. 𝟓)
(𝟒. 𝟔)
(𝟒. 𝟕)
Where:
𝐝𝐩 = 𝐝𝐫𝐨𝐩𝐥𝐞𝐭 𝐝𝐢𝐚𝐦𝐞𝐭𝐞𝐫
𝛒𝐠 = 𝐠𝐚𝐬 𝐝𝐞𝐧𝐬𝐢𝐭𝐲 , 𝐈𝐛/𝐟𝐭 𝟑
𝐮 = 𝒔𝒖𝒔𝒑𝒆𝒏𝒅𝒊𝒏𝒈 𝐠𝐚𝐬 𝐯𝐞𝐥𝐨𝐜𝐢𝐭𝐲
𝒅 = 𝒊𝒏𝒔𝒊𝒅𝒆 𝒅𝒊𝒂𝒎𝒆𝒕𝒆𝒓 𝒐𝒇 𝒔𝒆𝒑𝒂𝒓𝒂𝒕𝒐𝒓
𝐤 = 𝐞𝐦𝐩𝐫𝐢𝐜𝐚𝐥 𝐜𝐨𝐧𝐬𝐭𝐚𝐧𝐭
𝛒𝐨 = 𝐨𝐢𝐥 𝐝𝐞𝐧𝐬𝐢𝐭𝐲 , 𝐈𝐛/𝐟𝐭 𝟑
𝐠 = 𝐚𝐜𝐜𝐞𝐥𝐞𝐫𝐚𝐭𝐢𝐨𝐧 𝐝𝐮𝐞 𝐭𝐨 𝐠𝐫𝐚𝐯𝐢𝐭𝐲.
𝒄=
𝟎.𝟓
𝟐𝒈ൗ
= 𝒔𝒆𝒑𝒂𝒓𝒂𝒕𝒆 𝒄𝒐𝒏𝒔𝒕𝒂𝒏𝒕
𝟑𝒌
𝒒𝒈 = gas flow rate, scf/day
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Separation Design
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A- Capacity of vertical Separators:
1. Gas Capacity:
Apply Material balance equation on gas under separator and standard condition
𝒒𝒈 𝝆𝒈 = 𝒒𝒈 𝒔.𝒄 𝝆𝒈 𝒔.𝒄
(𝟒. 𝟖)
Where:
•
𝑞𝑔 𝑠.𝑐 = 𝑔𝑎𝑠 𝑓𝑙𝑜𝑤 𝑟𝑎𝑡𝑒 𝑎𝑡 𝑆. 𝐶. 𝑠𝑐𝑓/𝑑𝑎𝑦
•
𝜌𝑔 𝑠.𝑐 = 𝑑𝑒𝑛𝑠𝑖𝑡𝑦 𝑜𝑓 𝑔𝑎𝑠 𝑎𝑡 𝑆. 𝐶. 𝐼𝑏/𝑓𝑡 3
•
𝜌𝑔 =
𝑃𝑀𝑎
𝑍𝑅𝑇
𝑃𝑠𝑐 𝑀𝑎
𝜌𝑔 𝑠𝑐 =
𝑍𝑠𝑐 𝑅𝑇𝑠𝑐
•
𝛾𝑔 =
•
𝑀𝑎 = 𝑎𝑝𝑝𝑎𝑟𝑒𝑛𝑡 𝑚𝑜𝑙𝑢𝑐𝑙𝑢𝑎𝑟 𝑤𝑒𝑖𝑔ℎ𝑡
•
•
𝑅 = 𝑢𝑛𝑖𝑣𝑒𝑟𝑠𝑎𝑙 𝑔𝑎𝑠 𝑐𝑜𝑛𝑠𝑡𝑎𝑛𝑡 , 10.73
𝛾𝑔 = 𝑔𝑎𝑠 𝑔𝑟𝑎𝑣𝑖𝑡𝑦
•
•
•
𝑍 = 𝑔𝑎𝑠 𝑑𝑒𝑣𝑎𝑖𝑡𝑖𝑜𝑛 𝑓𝑎𝑐𝑡𝑜𝑟
𝑇 = 𝑡𝑒𝑚𝑝𝑎𝑒𝑡𝑢𝑟𝑒 , ˚𝑅
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𝑀𝑎
𝑀𝑎
=
𝑀 𝑎𝑖𝑟
29
Separation Design
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A- Capacity of vertical Separators:
1. Gas Capacity:
• Substituting all above into equation (4.8):
𝟎.𝟓
𝝅 𝟐 (𝝆𝒐 −𝝆𝒈 )൘
𝑷𝑴𝒂
𝒅
𝒄
𝝆
𝒈
𝟒
𝒁𝑹𝑻
𝒒𝒈 𝒔𝒄 =
𝑷𝒔𝒄 𝑴𝒂
𝒁𝒔𝒄 𝑹𝑻𝒔𝒄
• In field unit;
0.5
𝜌𝑜
−
𝜌𝑔
𝑃 𝑇𝑠𝑐
𝒒𝒈 𝒔𝒄 = 67824 × 10−6 𝑑 2 𝑐
𝜌𝑔
𝑍 𝑇 𝑃𝑠𝑐
𝟎.𝟓
𝑷
(𝝆𝒐 −𝝆𝒈 )
൘𝝆
𝒒𝒈 𝒔𝒄 = 𝟐. 𝟒 𝒅 𝒄
𝒈
𝒁𝑻
𝟐
• Where:
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𝑞𝑔 𝑠.𝑐 = 𝑔𝑎𝑠 𝑓𝑙𝑜𝑤 𝑟𝑎𝑡𝑒 𝑎𝑡 𝑆. 𝐶. 𝑠𝑐𝑓/𝑑𝑎𝑦
𝑑 = 𝑖𝑛𝑠𝑖𝑑𝑒 𝑑𝑎𝑖𝑚𝑒𝑡𝑒𝑟 𝑜𝑓 𝑠𝑒𝑝𝑎𝑟𝑎𝑡𝑜𝑟 , 𝑖𝑛
𝑇𝑠𝑐 = 𝑠𝑡𝑎𝑛𝑑𝑎𝑟𝑑 𝑡𝑒𝑚𝑝. 60 ℉
(𝟒. 𝟗)
(𝟒. 𝟏𝟎)
(𝟒. 𝟏𝟏)
𝑃 = 𝑠𝑒𝑝𝑎𝑟𝑎𝑡𝑜𝑟 𝑜𝑝𝑒𝑟𝑎𝑡𝑖𝑛𝑔 𝑝𝑟𝑒𝑠𝑠𝑢𝑟𝑒, 𝑝𝑠𝑖
𝑃𝑠𝑐 = 𝑠𝑡𝑎𝑛𝑑𝑎𝑟𝑑 𝑝𝑟𝑒𝑠𝑠𝑢𝑟𝑒, 14.7 𝑝𝑠𝑖
𝑇 = 𝑠𝑒𝑝𝑎𝑟𝑎𝑡𝑜𝑟 𝑜𝑝𝑒𝑟𝑎𝑡𝑖𝑛𝑔 𝑡𝑒𝑚𝑝. , ˚𝑅
Separation Design
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A- Capacity of vertical Separators:
2. Oil Capacity:
• Oil capacity design depend on retention time; therefore, the time should be enough
to give solution gas in oil the change to be freely.
• For most application retention times are between 30 second to 3 minutes have been
found to be sufficient. Where foaming crude is present retention time up to four times
this amount may be needed.
𝜋
𝑉𝑜 = 𝑑 2 ℎ𝑜
4
𝑉𝑜
𝑞𝑜 𝑎𝑐𝑡𝑢𝑎𝑙 =
𝑡
𝜋 2
𝑑 ℎ𝑜൘
4
𝑞𝑜 𝑎𝑐𝑡𝑢𝑎𝑙 =
𝑡 ×
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4.12
4.13
1440
5.615
4.14
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A- Capacity of vertical Separators:
2. Oil Capacity:
𝑑 2 ℎ𝑜ൗ
𝑞𝑜 𝑎𝑐𝑡𝑢𝑎𝑙 = 201.4
𝑡
4.15
• And , for rated oil capacity under separator condition , bbl/day:
𝑞𝑜 𝑟 = 1Τ2 𝑞𝑜 𝑎𝑐𝑡𝑢𝑎𝑙
𝑑 2 ℎ𝑜ൗ
𝑞𝑜 𝑟 = 100.7
𝑡
• Where:
•
•
𝑉𝑜 = 𝑣𝑜𝑙𝑢𝑚𝑒 𝑜𝑓 𝑜𝑖𝑙 𝑠𝑒𝑐𝑡𝑖𝑜𝑛, 𝑓𝑡 3
𝒅 = 𝒊𝒏𝒔𝒊𝒅𝒆 𝒅𝒊𝒂𝒎𝒆𝒕𝒆𝒓 𝒐𝒇 𝒔𝒆𝒑𝒂𝒓𝒂𝒕𝒐𝒓
•
ℎ𝑜 = ℎ𝑒𝑖𝑔ℎ𝑡 𝑜𝑓 𝑜𝑖𝑙 𝑠𝑒𝑐𝑡𝑖𝑜𝑛 , 𝑓𝑡
•
•
𝑞𝑜 𝑎𝑐𝑡𝑢𝑎𝑙 = 𝑎𝑐𝑢𝑡𝑎𝑙 𝑜𝑖𝑙 𝑐𝑎𝑝𝑎𝑐𝑖𝑡𝑦, 𝑏𝑏𝑙/𝑑𝑎𝑦
𝑞𝑜 𝑟 = rated oil capacity under separator
condition , bbl/day
•
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𝑡 = 𝑟𝑒𝑡𝑒𝑛𝑡𝑖𝑜𝑛 𝑡𝑖𝑚𝑒, 𝑚𝑖𝑛𝑢𝑡𝑒
4.16
Separation Design
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A- Capacity of vertical Separators:
• For oil and gas capacities calculations can determine inside diameter of separator.
Height of gas section ( gas section volume), height of oil section (oil section volume),
and them separator volume ( gas section + oil section).
• The volume ( Size, d) of vertical separator can be estimated approximately (ignore
temperature, gas density and some factors effects), if the following data are known:
1. Operating pressure.
2. Oil gravity (API).
3. Gas capacity ( daily gas production MMcf/day) and
By figure below determine diameter (d).
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Separation Design
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A- Capacity of vertical Separators:
2. Oil Capacity:
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Estimate diameter of vertical separator
Separation Design
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A- Capacity of vertical Separators:
• Note:
• 𝐶𝑎𝑝𝑎𝑐𝑖𝑡𝑦 𝑜𝑓 𝑣𝑒𝑟𝑡𝑖𝑐𝑎𝑙 𝑠𝑒𝑝𝑎𝑟𝑎𝑡𝑜𝑟 = 9.7 × 10−4 𝑑2
, 𝑑𝑖𝑎𝑚𝑒𝑡𝑒𝑟 𝑖𝑛 𝑖𝑛𝑐ℎ.
• 𝐺𝑒𝑛𝑒𝑟𝑎𝑙𝑙𝑦 ℎ𝑒𝑖𝑔ℎ𝑡 𝑜𝑓 𝑔𝑎𝑠 𝑠𝑒𝑐𝑡𝑖𝑜𝑛 = ℎ𝑔 = 2 𝑑
• 𝐸𝑠𝑡𝑖𝑚𝑎𝑡𝑖𝑛𝑔 ℎ𝑒𝑖𝑔ℎ𝑡 𝑜𝑓 𝑜𝑖𝑙 𝑠𝑒𝑐𝑡𝑖𝑜𝑛 = ℎ𝑜
• Volume of oil section 𝑉𝑜 = 𝑜𝑖𝑙 𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝑟𝑎𝑡𝑒 × 𝑟𝑒𝑡𝑒𝑛𝑡𝑖𝑜𝑛 𝑡𝑖𝑚𝑒
• ℎ𝑒𝑖𝑔ℎ𝑡 𝑜𝑓 𝑜𝑖𝑙 𝑠𝑒𝑐𝑡𝑖𝑜𝑛 = ℎ𝑜 = 𝑉𝑜 , 𝑏𝑏𝑙Τ𝑆𝑒𝑝𝑎𝑟𝑎𝑡𝑜𝑟 𝑐𝑎𝑝𝑎𝑐𝑖𝑡𝑦 𝑏𝑏𝑙/𝑓𝑡
• Height of vertical separator = 𝐻 = ℎ𝑜 + ℎ𝑔
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Separation Design
44
A- Capacity of vertical Separators:
Example 4.1:
Calculate gas and oil rated capacity for vertical separator, use the following data:
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𝑳 = 𝟏𝟎 𝒇𝒕
𝑨𝑷𝑰 = 𝟒𝟓°
𝒉𝒐 = 𝟑, 𝟐𝟓 𝒇𝒕
𝑷 = 𝟒𝟎𝟎 𝒑𝒔𝒊
𝒅 = 𝟐𝟒 𝒊𝒏
𝑻 = 𝟔𝟎 ℉
𝜸𝒈 = 𝟎. 𝟖
𝒄 = 𝟎. 𝟏𝟔𝟕
𝒛=𝟏
𝒕 = 𝟏 𝒎𝒊𝒏𝒖𝒕𝒆
Separation Design
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A- Capacity of vertical Separators:
Example 4.1:
Solution:
1- Gas Capacity:
𝒒𝒈 𝒔𝒄 = 67824 × 10
−6 2
𝑑 𝑐
𝜌𝑜 − 𝜌𝑔 0.5 𝑃 𝑇𝑠𝑐
𝜌𝑔
𝑍 𝑇 𝑃𝑠𝑐
141.5
3
−
131.5
≫
𝛾
=
0.8017
≫
𝜌
=
0.8017
×
62.4
=
50.02
𝐼𝑏/𝑓𝑡
𝑜
𝑜
𝛾𝑜
𝑃𝑀𝑤𝑡 𝑔
𝑃𝑀𝑎𝑖𝑟 𝛾𝑔
400 ×0.8×29
3
𝐴𝑃𝐼 =
𝜌𝑔 =
𝑍𝑅𝑇
=
𝑍𝑅𝑇
=
1×10.73×520
= 1.66 𝐼𝑏/ 𝑓𝑡
50.02 − 1.66
−6
2
𝒒𝒈 𝒔𝒄 = 67824 × 10 (24/12) 0.167
1.66
𝒒𝒈 𝒔𝒄 =6.66 MMSCF/Day
1- Oil Capacity:
𝑑 2 ℎ𝑜ൗ
𝑞𝑜 𝑟 = 100.7
𝑡
(2)2 3.25ൗ
𝑞𝑜 𝑟 = 100.7
1 = 1309 𝑏𝑏𝑙/𝑑𝑎𝑦
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0.5
400 × 520
1 × 520 × 14.7
Separation Design
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A- Capacity of vertical Separators:
Example 4.2:
Vertical separator has gas capacity = 100 MMcf/day, oil capacity = 7200
bbl/day, and operation pressure = 400 psi, API = 70°, t = 0.5 minute. What is
the separator design (i.e. L &d)?
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Separation Design
47
A- Capacity of vertical Separators:
Example 4.2:
Solution:
1- Use figure before to determine d, by P = 400 psi, API = 70°, Qg = 100 MMcf/day
𝑑 = 72 𝑖𝑛𝑐ℎ ≫≫ ℎ𝑔 = 2𝑑 = 2 × 72Τ12 = 12 𝑓𝑡
2- Use equ. 4.16 to calculate ℎ𝑜 :
𝑑 2 ℎ𝑜ൗ
𝑞𝑜 𝑎𝑐𝑡𝑢𝑎𝑙 = 201.4
𝑡
7200 = 201.4
(72Τ12)2 ℎ𝑜ൗ
0.5
≫≫ ℎ𝑜 = 0.5 ft
𝑳 = ℎ𝑜 + ℎ𝑔
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𝑳 = 0.5 + 12 = 12.5 𝑓𝑡
Separation Design
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A- Capacity of vertical Separators:
Example 4.2:
Solution:
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Separation Design
49
B- Horizontal Separators Design:
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Separation Design
50
B- Capacity of Horizontal Separators:
1. Gas Capacity:
• Total section area:
𝐴𝑡 =
𝜋
4
𝑑2
4.17
• Area of gas section = 1/2 total area
𝐴𝑔 =
𝜋 2
𝜋 2
𝑑 → 𝐴𝑔 =
𝑑
8
4 𝑒
4.18
• From equation 4.18. : 𝒅𝒆 = 𝟎. 𝟓 𝒅
• From equation (4.10):
𝜌𝑜 − 𝜌𝑔
𝒒𝒈 𝒔𝒄 = 67824 × 10−6 𝑑𝑒2 𝑐
𝜌𝑔
0.5
𝑃 𝑇𝑠𝑐
𝐿 0.56
𝑍 𝑇 𝑃𝑠𝑐 10
4.19
• Where
d = separator diameter
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de = equivalent diameter
L = height of separator, ft
Separation Design
51
B- Capacity of Horizontal Separators:
2. Oil Capacity:
a) Mono – Tube:
𝑉𝑜
1440
𝑞𝑜 𝑎𝑐𝑡𝑢𝑎𝑙 =
×
𝑡
5.615
𝜋 𝐿 2
𝑉𝑜 =
𝑑
4 2
4.20
4.21
• Substitute eq. (4.21) in (4.20)
𝐿 𝑑2
𝑞𝑜𝑎𝑐𝑡𝑢𝑎𝑙 = 100.7
𝑡
• And:
𝑞𝑜 𝑟 = 50.35
𝐿 𝑑2
𝑡
4.22
4.23
• Where:
d = inside diameter of separator, ft qo = oil capacity bbl/day t = retention time, minute
L = height of separator, ft , qor = rated oil capacity under separator condition bbl/day
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Separation Design
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B- Capacity of Horizontal Separators:
2. Oil Capacity:
b) Dual – Tube:
𝑉𝑜 =
𝜋
𝐿 𝑑2
4
4.24
𝐿 𝑑2
𝑞𝑜𝑎𝑐𝑡𝑢𝑎𝑙 = 201.4
𝑡
And:
𝑞𝑜 𝑟 = 100.7
𝐿 𝑑2
𝑡
4.25
4.26
• Graphically the volume (size, d) of a horizontal separator can be estimated approximately, if
the following data are known:
1. Operating pressure (psia)
2. Oil gravity (API)
3. Gas capacity (daily gas production, MMcf/day)
4. Liquid residence volume, bbl
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And by figures below determine (d)
Separation Design
53
B- Capacity of Horizontal Separators:
2. Oil Capacity:
Estimate gas capacity of horizontal separator
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Separation Design
54
B- Capacity of Horizontal Separators:
2. Oil Capacity:
Estimate diameter of horizontal separator
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Separation Design
55
B- Capacity of Horizontal Separators:
Example 4.3:
A mono tube horizontal separator has;
𝑳 = 𝟏𝟎 𝒇𝒕
𝑨𝑷𝑰 = 𝟑𝟓°
𝒅 = 𝟐𝟒 𝒊𝒏
𝑷 = 𝟒𝟎𝟎 𝒑𝒔𝒊
𝜸𝒈 = 𝟎. 𝟕
𝑻 = 𝟔𝟎 ℉
𝒛 = 𝟎. 𝟗𝟎𝟗
𝒄 = 𝟎. 𝟑𝟖𝟐
𝒕 = 𝟎. 𝟓 𝒎𝒊𝒏𝒖𝒕𝒆
Calculate:
1. 𝒒𝒐 𝒓 when t = 1 minute.
2. de for-gas section if
3. 𝒒𝒈 𝒔𝒄
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Ag = 0.5 At.
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56
B- Capacity of Horizontal Separators:
Example 4.3:
Solution:
1. Oil Capacity: use equation 4.23:
𝐿 𝑑2
𝑞𝑜 𝑟 = 50.35
𝑡
(24/12)2 10ൗ
𝑞𝑜 𝑟 = 50.35
1 = 2014 𝑏𝑏𝑙/𝑑𝑎𝑦
2- use equation 4.18:
𝜋
𝐴𝑡 =
(24/12)2 = 3.142 𝑓𝑡 2
4
𝐴𝑔 = 0.5 𝐴𝑡
𝐴𝑔 = 1.571 𝑓𝑡 2
𝜋 2
𝐴𝑔 =
𝑑 >≫≫ 𝑑𝑒 = 1.414 𝑓𝑡
4 𝑒
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Separation Design
57
B- Capacity of Horizontal Separators:
Example 4.3:
Solution:
3. Use equation 4.19 to calculate gas capacity:
𝜌𝑜 − 𝜌𝑔
𝒒𝒈 𝒔𝒄 = 67824 × 10−6 𝑑𝑒 2 𝑐
𝜌𝑔
𝐴𝑃𝐼 =
𝜌𝑔 =
0.5
𝑃 𝑇𝑠𝑐
𝐿 0.56
𝑍 𝑇 𝑃𝑠𝑐 10
141.5
3
−
131.5
≫
𝛾
=
0.85
≫
𝜌
=
0.85
×
62.4
=
53.03
𝐼𝑏/𝑓𝑡
𝑜
𝑜
𝛾𝑜
𝑃𝑀𝑤𝑡 𝑔
𝑍𝑅𝑇
=
𝑃𝑀𝑎𝑖𝑟 𝛾𝑔
𝑍𝑅𝑇
=
400 ×0.7×29
0.909×10.73×520
53.03 − 1.6
−6
2
𝒒𝒈 𝒔𝒄 = 67824 × 10 (1.414) 0.382
1.6
𝒒𝒈 𝒔𝒄 =8.49 MMSCF/Day
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= 1.6 𝐼𝑏/ 𝑓𝑡 3
0.5
400 × 520
10 0.56
0.909 × 520 × 14.7 10
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58
B- Capacity of Horizontal Separators:
Example 4.4:
Horizontal separator has Qg = 50 MMCF/day, Qo = 4320 bbl/day,
P = 800 psi,
API = 70°, and t = 1 minute.
What is the separator design (i.e. L & d)?
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Separation Design
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B- Capacity of Horizontal Separators:
Example 4.4:
Solution:
1. Use figure ( before) to determine Ag, by P = 800 psi, API = 70° , Qg = 50 MMCF/day.
Ag = 5 ft²
1. Use figure ( before) to determine d, by Ag = 5 ft², and Vo = qo * t = (4320*1)/1440
Vo = 3 bbl.
d = 35 in , and L = 4d = 4*35 = 140 inch.
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Separation Design
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B- Capacity of Horizontal Separators:
Example 4.4:
Solution:
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Separation Design
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B- Capacity of Horizontal Separators:
Example 4.4:
Solution:
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C- Spherical Separator Design
No need
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Separation
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End of Lecture
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