IPE-TM-510-17 — How to Setup Compressor Circuits

1. Table of Contents 1

2. Purpose 1

3 General 1

4. Reciprocating Compressor with Spillback and Fixed Volume Pockets 2

5. Reciprocating Compressor with Spillback and No Fixed Volume Pockets 6

6. Centifugal Compressor with Fixed Speed Motor Driver and Suction Throttling Valve 10

7. Centrifugal Compressor with Turbine/Variable Speed Driver 13

2. Purpose

This procedure demonstrates the proper method of setting up the hydraulic circuits in NHP for various single stage compressor flow schemes.

3. General

For Inlet Volume Flow (ACFM) calculations, see DM-EQUIP-2073-519 Section 4.2. This calculation applies to centrifugal and reciprocating compressors.

For centrifugal compressor head calculations (Total Differential Head), see DM-EQUIP-2072-518 Section 4.2.

For centrifugal compressor power calculations, see DM-EQUIP-2072-518 Section 4.3.

4. Reciprocating Compressor with Spillback and Fixed Volume Pockets

The spillback is continuous and typically 10% of the main compressor flow. The simulation should include the spillback flow through the compressor. The simulation should have all spillback streams and equipment. The percentages listed below will be different if the spillback is not 10% of the net forward flow.

A fixed volume pocket is generally applied to reciprocating compressors when the following conditions are met (to be confirmed with the 509 specification, top of sheet 4):

Discharge pressure / suction pressure > 2.0
kW > 186.5 (BHP > 250 hp)

The Design Engineer shall adhere to the following (see Section Example 4 hydraulic tabulations):

Compressor Circuit:

The “Compressor Type” should be “Positive Displacement”.
The “Compressor Sub Type” should be “Reciprocating”.
The normal flow scenario factor should be 100% for the entire circuit.
The Design flow scenario factor for the entire circuit should be 110%. This extra 10% is to account for the compressor design margin.
The Alternate flow scenario should be 50/60% (see BEDQ) if there is a turndown for the compressor. This flow rate may not be seen through the compressor but the rotating equipment specialist wants to see the raw data in hydraulics.
The compressor is the only unknown in the circuit.

Spillback Circuit:
The normal flow scenario is 100% assuming the correct spillback flow is in the simulation.
The Design flow scenario should be 50%. This is to account for the scenario when the main process flow increases and the spillback flow decreases and keeping the compressor flow constant.
The Alternate flow scenario should be 1200%. This is the factor to get the Design flow through the compressor on total spillback. (= compressor design flow/Spillback flow). See the example 4 values to understand how 1200% was calculated:
Design flow through compressor is 4379*1.1
Spillback flow is 398
4379*1.1/398≈1200%
Set the “Equipment Design Basis Flow Scenario” to “Alternate” for both pipes in the circuit.
For both pipes, use line code 10 and manually enter a max pressure drop of 5 psi/100’.

4.1 Section Example 4

The normal net forward flow is 3981 lb/h
Flow in stream 630 already includes the 10% spillback and is 4379 lb/h (3981*1.1)
Flow in stream 681 is 398 lb/h (10% of net forward flow)

Section Example 4 Hydraulics of Reciprocating Compressor with Spillback and Fixed Volume Pockets

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Circuit 21 : Stripper Offgas

Normal Design Alternate

PRESS 100.0% 110.0% 60.0%

DROP ------------------- ------------------- -------------------

LINE 100 PER NOZL PRESS INLET PRESS INLET PRESS INLET

SIZE EQ 100ft ELEV DROP PRESS DROP PRESS DROP PRESS

EQUIPMENT IDENTIFICATION IN ft psi ft psi psig psi psig psi psig

Stripper Receiver 23.2 13.64 12.31 17.71

LN-630 8 4.13 0.01 0.05 13.64 0.07 12.31 0.02 17.71

Offgas Compressor -84.33 13.59 -86.55 12.24 -77.55 17.69

Compressor Capacity,ACFM 296.8 326.5 178.1

Molecular Weight 48.7

Suction Temperature, °F 107

Discharge Temperature, °F 192

Suction Cp/Cv Ratio (Ideal) 1.112

Discharge Cp/Cv Ratio (Ideal) 1.099

LN-632 4 2.30 0.12 0.28 97.92 0.33 98.80 0.10 95.24

Stripper Offgas Compressor Spillback Spl 97.64 98.46 95.14

LN-633 4 1.58 0.10 0.16 97.64 0.19 98.46 0.06 95.14

Offgas Cooler (Shell) 10.0 3.16 97.49 3.83 98.27 1.14 95.09

LN-634 3 1.28 0.18 0.23 94.32 0.27 94.45 0.08 93.95

Static Head -1.2 0.09 94.10 0.09 94.17 0.09 93.86

Scrubber Inlet KO Drum 11.2 94.01 94.09 93.78

LN-635 2 1.03 0.35 0.36 94.01 0.44 94.09 0.13 93.78

Offgas Scrubber 15.2 0.15 93.50 0.15 93.50 0.15 93.50

Circuit 22 : Offgas Compressor Spillback

Normal Design Alternate

PRESS 100.0% 50.0% 1200.0%

DROP ------------------- ------------------- -------------------

LINE 100 PER NOZL PRESS INLET PRESS INLET PRESS INLET

SIZE EQ 100ft ELEV DROP PRESS DROP PRESS DROP PRESS

EQUIPMENT IDENTIFICATION IN ft psi ft psi psig psi psig psi psig

Stripper Offgas Compressor Spillback Spl 97.63 98.45 95.13

LN-681 3 1.27 0.00 0.01 97.64 0.00 98.46 0.73 95.14

Offgas Compressor Spillback CV: CV-1682 78.44 97.64 79.45 98.46 72.19 94.41

LN-682 3 1.27 0.01 0.02 19.20 0.00 19.01 2.52 22.23

Offgas Compressor Spillback Mixer 19.18 19.01 19.70

Section Example 4 Hydraulics of Reciprocating Compressor with Spillback and Fixed Volume Pockets

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Circuit 21 : Stripper Offgas

Normal Design Alternate

PRESS 100.0% 110.0% 60.0%

DROP ------------------- ------------------- -------------------

LINE 100 PER NOZL PRESS INLET PRESS INLET PRESS INLET

SIZE EQ 100ft ELEV DROP PRESS DROP PRESS DROP PRESS

EQUIPMENT IDENTIFICATION IN ft psi ft psi psig psi psig psi psig

Stripper Receiver 23.2 13.60 12.26 17.70

LN-630 8 4.13 0.01 0.06 13.60 0.07 12.26 0.02 17.70

Offgas Compressor -84.49 13.54 -86.74 12.19 -77.61 17.68

Compressor Capacity,ACFM 300.8 330.9 180.5

Molecular Weight 48.8

Suction Temperature, °F 107

Discharge Temperature, °F 192

Suction Cp/Cv Ratio (Ideal) 1.112

Discharge Cp/Cv Ratio (Ideal) 1.099

LN-632 4 2.30 0.12 0.28 98.03 0.34 98.93 0.10 95.28

Stripper Offgas Compressor Spillback Spl 97.75 98.59 95.18

LN-633 4 1.58 0.10 0.16 97.75 0.20 98.59 0.06 95.18

Offgas Cooler (Shell) 10.0 3.25 97.59 3.93 98.39 1.17 95.12

LN-634 3 1.28 0.18 0.23 94.34 0.28 94.46 0.08 93.95

Static Head -1.2 0.09 94.10 0.09 94.18 0.09 93.87

Scrubber Inlet KO Drum 11.2 94.02 94.10 93.78

LN-635 2 1.03 0.36 0.37 94.02 0.45 94.10 0.13 93.78

Offgas Scrubber 15.2 0.15 93.50 0.15 93.50 0.15 93.50

Circuit 22 : Offgas Compressor Spillback

Normal Design Alternate

PRESS 100.0% 50.0% 1200.0%

DROP ------------------- ------------------- -------------------

LINE 100 PER NOZL PRESS INLET PRESS INLET PRESS INLET

SIZE EQ 100ft ELEV DROP PRESS DROP PRESS DROP PRESS

EQUIPMENT IDENTIFICATION IN ft psi ft psi psig psi psig psi psig

Stripper Offgas Compressor Spillback Spl 97.74 98.58 95.17

LN-681 3 1.27 0.00 0.01 97.75 0.00 98.59 0.75 95.18

Offgas Compressor Spillback CV: CV-1682 78.54 97.74 79.58 98.59 72.12 94.43

LN-682 3 1.27 0.01 0.02 19.20 0.00 19.01 2.60 22.30

Offgas Compressor Spillback Mixer 19.18 19.01 19.70

5. Reciprocating Compressor with Spillback and No Fixed Volume Pockets 1

The simulation will typically run with the compressor operating at its’ normal flow rate. However, the compressor can only operate at one flow rate. We want to run hydraulics showing the compressor at its’ rated flow rate. This section will explain how to properly setup this circuit. The simulation should include the spillback flow through the compressor. The simulation should have all spillback streams and equipment.

The Design Engineer shall adhere to the following (see Section Example 5 hydraulic tabulations):

Compressor Circuit:

The “Compressor Type” should be “Positive Displacement”.
The “Compressor Sub Type” should be “Reciprocating”.
The normal flow scenario factor should be 100% for the entire circuit.
Set the simulation stream factor to 110% on the compressor suction and discharge lines. This is to account for the compressor design margin. The compressor can only operate at one flow rate, which is the rated flow. Since the reciprocating compressor is a fixed volume machine, the compressor will not operate at its’ normal flow.
The Design flow scenario factor for the entire circuit should be 100%. The compressor design margin has already been accounted for in the normal flow scenario.
The Alternate flow scenario for the circuit should be 50/60% (see BEDQ) if there is a turndown for the compressor. This flow rate may not be seen through the compressor but the rotating equipment specialist wants to see the raw data in hydraulics.
The alternate flow factor should be 45% (if circuit alternate flow factor is 50%) or 55% (if circuit alternate flow factor is 60%) for the compressor, suction line and discharge line. The alternate flows through the compressor should not include the 10% design margin (=TD%*(net forward flow + SB flow)/hyd normal flow). See the example 5 values to understand how 55% was calculated:
The alternate flow is 60% of the net forward flow plus the spillback
0.6 * 4379 / 4817 = 55%
The compressor is the only unknown in the circuit.

Spillback Circuit:
A stream factor (210%) is applied to both streams. Since the normal flow through the compressor was increased by 110% to account for compressor design margin, the spillback has to be increased to make up the difference.

1 This section can also be used to model a diaphragm type compressor in hydraulics.
See the example 5 values to understand how 210% was calculated:
Compressor flow in the simulation is 4379 lb/h. The normal flow has been increased to 4817 lb/h to account for compressor design margin.
The spillback flow needs to be 836 lb/h (4817-3981=836) to get the compressor flow to its’ rated value.
The spillback stream flow is 398 lb/h.
The simulation stream factor is 836/398=210%.
The Design flow scenario for the circuit should be 24%. This is to account for the scenario when the main compressor flow increases and the spillback flow decreases to 5%. The compressor flow must remain constant. See the example 5 values to understand how 24% was calculated:
The spillback is 5% of the net forward flow (3981*0.05=199 lb/h)
199/836=24%
The Alternate flow scenario should be around 576%. This is the factor to get the Design flow through the compressor on total spillback (compressor design flow/SB flow). See the example 5 values to understand how 576% was calculated:
Design flow through compressor is 4817 lb/h
Spillback flow is 836
4817/836=576%
Set the “Equipment Design Basis Flow Scenario” to “Alternate” for both pipes in the circuit.
For both pipes, use line code 10 and manually enter a max pressure drop of 5 psi/100’.

5.1 Section Example 5

The normal net forward flow is 3981 lb/h
Flow in stream 630 already includes the 10% spillback and is 4379 lb/h (3981*1.1)
In order to account for compressor design margin, the simulation stream factor was set to 110%. The rated flow through the compressor is 4379*1.1=4817 lb/h.
Flow in stream 681 is 398 lb/h (10% of net forward flow)

Section Example 5

Reciprocating Compressor with Spillback and No Fixed Volume Pockets

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Circuit 21 : Stripper Offgas

Normal Design Alternate

PRESS 100.0% 100.0% 60.0%

DROP ------------------- ------------------- -------------------

LINE 100 PER NOZL PRESS INLET PRESS INLET PRESS INLET

SIZE EQ 100ft ELEV DROP PRESS DROP PRESS DROP PRESS

EQUIPMENT IDENTIFICATION IN ft psi ft psi psig psi psig psi psig

Stripper Receiver 23.2 13.64 12.31 17.71

LN-630 (Strm=110.00%,Alt=55%) 8 4.13 0.02 0.06 13.64 0.06 12.31 0.02 17.71

Offgas Compressor(Alt=55%) -84.38 13.58 -85.72 12.24 -77.54 17.69

Compressor Capacity,ACFM 342.8 359.7 164.6

Molecular Weight 48.7

Suction Temperature, °F 107

Discharge Temperature, °F 192

Suction Cp/Cv Ratio (Ideal) 1.112

Discharge Cp/Cv Ratio (Ideal) 1.099

LN-632 (Strm=110.00%,Alt=55%) 4 2.30 0.14 0.33 97.96 0.33 97.96 0.10 95.23

Stripper Offgas Compressor Spillback Spl 97.63 97.63 95.13

LN-633 4 1.58 0.10 0.16 97.63 0.16 97.63 0.06 95.13

Offgas Cooler (Shell) 10.0 3.16 97.47 3.16 97.47 1.14 95.07

LN-634 3 1.28 0.18 0.23 94.31 0.23 94.31 0.08 93.94

Static Head -1.2 0.07 94.08 0.07 94.08 0.07 93.85

Scrubber Inlet KO Drum 11.2 94.01 94.01 93.78

LN-635 2 1.03 0.35 0.36 94.01 0.36 94.01 0.13 93.78

Offgas Scrubber 15.2 0.15 93.50 0.15 93.50 0.15 93.50

Circuit 22 : Offgas Compressor Spillback

Normal Design Alternate

PRESS 100.0% 24.0% 576.0%

DROP ------------------- ------------------- -------------------

LINE 100 PER NOZL PRESS INLET PRESS INLET PRESS INLET

SIZE EQ 100ft ELEV DROP PRESS DROP PRESS DROP PRESS

EQUIPMENT IDENTIFICATION IN ft psi ft psi psig psi psig psi psig

Stripper Offgas Compressor Spillback Spl 97.63 97.63 95.13

LN-681 (Strm=210.00%) 3 1.27 0.02 0.02 97.64 0.00 97.64 0.74 94.92

Offgas Compressor Spillback CV: CV-1682 78.36 97.62 78.63 97.64 71.91 94.18

LN-682 (Strm=210.00%) 3 1.27 0.06 0.08 19.26 0.00 19.01 2.56 22.27

Offgas Compressor Spillback Mixer 19.18 19.01 19.70 Section Example 5 (continued)

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CASE B without its written permission. EFID

Circuit 21 : Stripper Offgas

Normal Design Alternate

PRESS 100.0% 100.0% 60.0%

DROP ------------------- ------------------- -------------------

LINE 100 PER NOZL PRESS INLET PRESS INLET PRESS INLET

SIZE EQ 100ft ELEV DROP PRESS DROP PRESS DROP PRESS

EQUIPMENT IDENTIFICATION IN ft psi ft psi psig psi psig psi psig

Stripper Receiver 23.2 13.60 12.26 17.70

LN-630 (Strm=110.00%,Alt=55%) 8 4.13 0.02 0.07 13.60 0.07 12.26 0.02 17.70

Offgas Compressor(Alt=55%) -84.54 13.53 -85.89 12.19 -77.60 17.68

Compressor Capacity,ACFM 348.0 365.4 166.9

Molecular Weight 48.8

Suction Temperature, °F 107

Discharge Temperature, °F 192

Suction Cp/Cv Ratio (Ideal) 1.112

Discharge Cp/Cv Ratio (Ideal) 1.099

LN-632 (Strm=110.00%,Alt=55%) 4 2.30 0.15 0.34 98.08 0.34 98.08 0.10 95.27

Stripper Offgas Compressor Spillback Spl 97.74 97.74 95.17

LN-633 4 1.58 0.10 0.16 97.74 0.16 97.74 0.06 95.17

Offgas Cooler (Shell) 10.0 3.25 97.57 3.25 97.57 1.17 95.11

LN-634 3 1.28 0.18 0.23 94.33 0.23 94.33 0.08 93.94

Static Head -1.2 0.07 94.09 0.07 94.09 0.07 93.86

Scrubber Inlet KO Drum 11.2 94.02 94.02 93.78

LN-635 2 1.03 0.36 0.37 94.02 0.37 94.02 0.13 93.78

Offgas Scrubber 15.2 0.15 93.50 0.15 93.50 0.15 93.50

Circuit 22 : Offgas Compressor Spillback

Normal Design Alternate

PRESS 100.0% 24.0% 576.0%

DROP ------------------- ------------------- -------------------

LINE 100 PER NOZL PRESS INLET PRESS INLET PRESS INLET

SIZE EQ 100ft ELEV DROP PRESS DROP PRESS DROP PRESS

EQUIPMENT IDENTIFICATION IN ft psi ft psi psig psi psig psi psig

Stripper Offgas Compressor Spillback Spl 97.74 97.74 95.17

LN-681 (Strm=210.00%) 3 1.27 0.02 0.02 97.75 0.00 97.75 0.76 94.95

Offgas Compressor Spillback CV: CV-1682 78.46 97.72 78.73 97.75 71.84 94.19

LN-682 (Strm=210.00%) 3 1.27 0.06 0.08 19.26 0.00 19.01 2.64 22.35

Offgas Compressor Spillback Mixer 19.18 19.01 19.70

6. Centrifugal Compressor with Fixed Speed Motor Driver and Suction Throttling Valve

NHP will generate the compressor curve with 100/100% point set at the design flow scenario with the governing process case and the control valve pressure drop set equal to the value that the end user entered on the control valve form. For all other flow scenarios and process cases, NHP will calculate the required control valve pressure drop to get the calculated flow-head combination on the generated compressor curve.

The Design Engineer shall adhere to the following (see Section Example 6 hydraulic tabulations):

Set the “Compressor Type” to “Dynamic”.
Set the “Compressor SubType” to “Centrifugal”.
Set the “Driver Type” to “Fixed Speed Motor”.
The “Flow Control: Speed” should be set to “No”.
The design flow scenario will typically be set at 110%. The technology specific design manual may override this value with a different value.
Set the alternate flow scenario to the value in the BEDQ. If the value is 50%, consult with the rotating equipment specialist.
The control valve on the suction of the compressor must be set to “Hydraulic Balance”. Enter the value for “Valve pressure drop for design flow scenario” on the Pressure Drop Data tab. This value is supplied by the technology specialist. However, if one process case governs flow and horsepower while a different process case governs the compressor head (CCR Platforming), then the rotating equipment specialist may increase this value to ensure the compressor is properly specified. This circuit must have one “hydraulic balance” control valve. The circuit can have additional control valves but they must be set as “FixedCv”.
The suction valve should be the last equipment just upstream of the compressor. Use “short run” equivalent length ABC factors for the line segment between the suction valve and the compressor. Inflection Point Engineering reports the suction pressure upstream of the suction throttle valve for fixed speed machines in the 508 specification not the compressor suction pressure. Hydraulics should not show a large pressure drop between the suction throttle valve and the compressor due to using compressor suction equivalent lengths.
For the line just upstream of the suction valve, use “compressor suction” equivalent length ABC factors.
The hydraulic balance control valve and compressor are the unknowns in the circuit.

Section Example 6

Hydraulics of Centrifugal Compressor with Fixed Speed

Motor Driver and Suction Throttling Valve

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Circuit 1 : Regeneration

Normal Design Alternate

PRESS 100.0% 110.0% 60.0%

DROP ------------------- ------------------- -------------------

LINE 100 PER NOZL PRESS INLET PRESS INLET PRESS INLET

SIZE EQ 100ft ELEV DROP PRESS DROP PRESS DROP PRESS

EQUIPMENT IDENTIFICATION IN ft psi ft psi psig psi psig psi psig

Regen Compressor Suction Drum 9.4 43.81 41.46 50.97

LN-724 14 3.69 0.19 0.70 43.81 0.84 41.46 0.25 50.97

Regen Compressor Flow Venturi: FD-1712 14 0.21 43.11 0.26 40.62 0.08 50.72

LN-726 16 6.78 0.12 0.84 42.90 1.02 40.36 0.30 50.64

Regeneration Compressor HCV: CV-1610 8.71 42.06 1.00 39.34 34.75 50.34

LN-725 16 0.98 0.12 0.12 33.35 0.14 38.34 0.04 15.59

Regeneration Compressor *Gov* -103.69 33.23 -114.87 38.20 -68.14 15.55

Compressor Head,ft 43494.43 43612.16 44795.40

Compressor Capacity,ACFM 5137.6 5120.3 4884.5

Molecular Weight 28.2

Suction Temperature, °F 99

Discharge Temperature, °F 391

Suction Cp/Cv Ratio (Ideal) 1.395

Discharge Cp/Cv Ratio (Ideal) 1.378

Speed

LN-728 10 4.81 0.49 2.37 136.92 2.87 153.07 0.85 83.69

Compressor Discharge Cooler (Shell) 10.0 3.00 134.55 3.63 150.20 1.08 82.84

LN-730 10 2.83 0.33 0.92 131.55 1.11 146.57 0.33 81.76

Regen Compressor Discharge Drum 8.8 130.62 145.46 81.42

Section Example 6 (continued)

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CASE B without its written permission. EFID

Circuit 1 : Regeneration

Normal Design Alternate

PRESS 100.0% 110.0% 70.0%

DROP ------------------- ------------------- -------------------

LINE 100 PER NOZL PRESS INLET PRESS INLET PRESS INLET

SIZE EQ 100ft ELEV DROP PRESS DROP PRESS DROP PRESS

EQUIPMENT IDENTIFICATION IN ft psi ft psi psig psi psig psi psig

Regen Compressor Suction Drum(Des=100%) 9.4 45.23 43.18 51.48

LN-724 14 3.69 0.18 0.66 45.23 0.80 43.18 0.24 51.48

Regen Compressor Flow Venturi: FD-1712 14 0.20 44.58 0.24 42.39 0.07 51.25

LN-726 16 6.78 0.12 0.79 44.38 0.96 42.14 0.29 51.18

Regeneration Compressor HCV: CV-1610 14.37 43.58 7.54 41.19 37.63 50.89

LN-725 16 0.98 0.12 0.11 29.21 0.14 33.64 0.04 13.26

Regeneration Compressor -99.64 29.10 -109.73 33.51 -67.57 13.22

Compressor Head,ft 42291.76 42311.00 44201.41

Compressor Capacity,ACFM 5314.8 5312.0 5002.8

Molecular Weight 29.8

Suction Temperature, °F 100

Discharge Temperature, °F 378

Suction Cp/Cv Ratio (Ideal) 1.376

Discharge Cp/Cv Ratio (Ideal) 1.356

Speed

LN-728 10 4.81 0.46 2.21 128.74 2.67 143.24 0.79 80.79

Compressor Discharge Cooler (Shell) 10.0 2.80 126.54 3.39 140.57 1.01 80.00

LN-730 10 2.83 0.31 0.87 123.73 1.05 137.18 0.31 78.99

Regen Compressor Discharge Drum 8.8 122.86 136.13 78.68

(Des=100%)

7. Centrifugal Compressor with Turbine/Variable Speed Driver

The Design Engineer shall adhere to the following (see Section Example 7 hydraulic tabulations):

Set the “Compressor Type” to “Dynamic”.
Set the “Compressor SubType” to “Centrifugal”.
Set the “Driver Type” to “Turbine” or “Variable Speed Motor”.
The “Flow Control: Speed” should be set to “No”.
The compressor is the unknown in the circuit.
NHP does not calculate flow-head curves for this type of machine.

Section Example 7

Hydraulics of Centrifugal Compressor with Turbine/Variable Speed Motor Driver

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CASE A without its written permission. EFID

Circuit 1 : Regeneration

Normal Design Alternate

PRESS 100.0% 110.0% 60.0%

DROP ------------------- ------------------- -------------------

LINE 100 PER NOZL PRESS INLET PRESS INLET PRESS INLET

SIZE EQ 100ft ELEV DROP PRESS DROP PRESS DROP PRESS

EQUIPMENT IDENTIFICATION IN ft psi ft psi psig psi psig psi psig

Regen Compressor Suction Drum(Des=100%) 9.4 51.26 50.48 53.65

LN-724 14 3.69 0.18 0.66 51.26 0.80 50.48 0.24 53.65

Regen Compressor Flow Venturi: FD-1712 14 0.20 50.60 0.24 49.68 0.07 53.42

LN-726 16 6.78 0.12 0.79 50.40 0.96 49.44 0.29 53.34

Regeneration Compressor -41.86 49.61 -49.66 48.48 -14.32 53.06

Compressor Head,ft 15871.76 18609.09 5755.74

Compressor Capacity,ACFM 3619.8 4053.1 2061.3

Molecular Weight 29.8

Suction Temperature, °F 100

Discharge Temperature, °F 378

Suction Cp/Cv Ratio (Ideal) 1.376

Discharge Cp/Cv Ratio (Ideal) 1.356

Speed

LN-728 10 4.81 0.46 2.21 91.47 2.67 98.14 0.79 67.37

Compressor Discharge Cooler (Shell) 10.0 2.80 89.27 3.39 95.47 1.01 66.58

LN-730 10 3.12 0.31 0.96 86.46 1.16 92.08 0.34 65.57

Regeneration Drier (Adsorbtion) 40.6 3.29 85.50 3.98 90.92 1.18 65.23

Section Example 7 (continued)

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CASE B without its written permission. EFID

Circuit 1 : Regeneration

Normal Design Alternate

PRESS 100.0% 110.0% 60.0%

DROP ------------------- ------------------- -------------------

LINE 100 PER NOZL PRESS INLET PRESS INLET PRESS INLET

SIZE EQ 100ft ELEV DROP PRESS DROP PRESS DROP PRESS

EQUIPMENT IDENTIFICATION IN ft psi ft psi psig psi psig psi psig

Regen Compressor Suction Drum 9.4 50.46 49.50 53.36

LN-724 14 3.69 0.19 0.70 50.46 0.84 49.50 0.25 53.36

Regen Compressor Flow Venturi: FD-1712 14 0.21 49.76 0.26 48.66 0.08 53.11

LN-726 16 6.78 0.12 0.84 49.55 1.02 48.40 0.30 53.04

Regeneration Compressor *Gov* -46.36 48.71 -55.04 47.38 -15.89 52.73

Compressor Head,ft 18576.87 21816.68 6746.11

Compressor Capacity,ACFM 3883.4 4362.7 2190.8

Molecular Weight 28.2

Suction Temperature, °F 99

Discharge Temperature, °F 391

Suction Cp/Cv Ratio (Ideal) 1.395

Discharge Cp/Cv Ratio (Ideal) 1.378

Speed

LN-728 10 4.81 0.49 2.37 95.06 2.87 102.42 0.85 68.62

Compressor Discharge Cooler (Shell) 10.0 3.00 92.69 3.63 99.55 1.08 67.77

LN-730 10 3.12 0.33 1.02 89.69 1.23 95.92 0.37 66.69

Regeneration Drier (Adsorbtion) 40.6 3.50 88.67 4.24 94.69 1.26 66.32