1. Zeochem Molecular Sieves The Right Choice
For Natural Gas Dehydration
Z3-04

2. NATURAL GAS DEHYDRATION - THE DUTY
Variety of technologies.
Gases to be dehydrated (MW 18-25) include
heavier associated gases,
straight natural gas,
sour gases.
Many plants use “turbo-expander“ technology to compress,chill-down and liquefy the natural gas
Dew points required of the order of -100°C.

3. NATURAL GAS DEHYDRATION - THE DUTY
Molecular sieves - accepted technology
Costs for the duty include
the energy used in pressure loss
The energy required for regeneration heating
the need to replace the molecular sieve charge - typically every 2-4 years.

4. Zeochem Z3-04 The Right Product For The Duty
Specially developed form of the A - type crystal
High purity A-type crystals give better kinetics hence shorter Mass Transfer Zone length
High equilibrium capacity for moisture
Improved Hydrothermal Stability - Less ageing in the presence of moisture plus heat
Already approved by and in extensive successful use at major natural gas processing companies.

5. Zeochem Z3-04 Natural Gas Dehydration
High static H2O Capacity %
High dynamic H2O Capacity %
Excellent Kinetics MTZ tests
High Crush Strength kp (2.5-5)
Low Attrition %
High Density kg / m3
Good Sphericity ie Low Pressure Drop
Exceptional Hydrothermal Stability

6. Zeochem Z3-04 Natural Gas Dehydration
High static H2O Capacity %
High dynamic H2O Capacity %
Excellent Kinetics MTZ tests
High Crush Strength kp (2.5-5)
Low Attrition %
High Density kg / m3
Good Sphericity ie Low Pressure Drop
Exceptional Hydrothermal Stability

7. Water Adsorption Capacity Statistics

8. Typical Adsorber Gas inlet Inert balls / floating screen
Saturated layer
MTZ
Fresh Sieve
Inert balls / fixed screen
Gas outlet

9. Mass Transfer Zone
Mass Transfer Zone measurements indicate the kinetics of the product
Shorter MTZ gives better kinetics
All product for regenerative purposes is routinely tested.
Zeochem product is shown to be better than competitive products.

10. Mass Transfer Zone

11. Kinetics

12. Mass Transfer Zone Length
Sample Designation
Mass Transfer Zone Length mm
Z mm
Standard 3A Grade
Z – 5.0 mm Natural Gas Grade

13. Zeochem Z3-04 For Natural Gas Dehydration
Crush Strength
Physical strength under compressive stress
Test measures the force required to crush beads/extrudates
Simulates the compressive forces acting on the material in service
All Z3-04 manufacturing lots are tested for crush strength to ensure long life in the field

14. Zeochem Z3-04 For Natural Gas Dehydration
Crush Strength
Zeochem’s proprietary bead forming and calcination processes yield exceptionally high crush strength, typically in excess of 9 kp for mm beads
Beads give a higher packed crush strength than extrudates
Compressive forces are distributed more evenly
Spherical beads have no sharp edges (cylindrical extrudates do) which can easily break off

15. Zeochem Z3-04 For Natural Gas Dehydration
Attrition
Tendency for material to attrite from friction against other beads or surfaces and gas flow
Test measures the amount of fines produced by attrition
Simulates the movement of beads/extrudates against each other during thermal swings
All Z3-04 manufacturing lots are tested for attrition strength to ensure long life in the field

16. Zeochem Z3-04 For Natural Gas Dehydration
Attrition
% material lost
as fines*
Zeochem Z mm bead 0.05
Competitor 1/16" extrudate 0.20
In Zeochem standard attrition test (method Si5/45)

17. Zeochem Z3-04 For Natural Gas Dehydration
High Density Product gives more efficient columns
Even packing
Better Flow Distribution
More Capacity per unit volume
Longer cycles in existing columns
Smaller design for new columns

18. Water Adsorption Capacity
Water adsorption capacity is measured before and after steaming
This simulates real-life conditions in the Adsorber during regeneration
Need to minimise loss in capacity

19. Water Adsorption Capacity
Sample Designation
Water Adsorption Capacity new
50 % RH
Water Adsorption Capacity Aged
Competitive sample 1/16"
21.4
19.7
Z mm
23.1
22.6

20. Freeze Thaw Test Sample Fines % Broken Beads % Z3-01 Standard 3A Grade
3.5 – 10 %
3.5 %
Z3-04
Natural Gas Grade
0.5 – 2.0 %
0.2 – 1.5 %

21. Zeochem Z3-04 For Natural Gas Dehydration
Lower Pressure Drop
Lower Compression Costs
Better Recovery of Product Streams
C3, C4, C5 plus

22. Pressure Drop Calculation
Modified Ergun Equation
Delta P / L = A U V + B R V 2
P = Pressure in psi
L = Length in feet
U = Viscosity in centipoises
R = Gas Density lb / ft3
V = Fluid Velocity ft / min
A,B = two (dimensional) constants

23. Constants For Ergun Equation
Particle Size A B mm mm
1-2 mm
1/8“ pellet (extr.)
1/16“ pellet (extr.)
8 mesh gran
silica gel

24. Zeochem Z3-04 For Natural Gas Dehydration
Hydrothermal Stability
Ability of the material to maintain high adsorption capacity after exposure to high heat and humidity
Test measures the retained capacity after accelerated aging in a hot, humid environment
Simulates the loss in crystallinity resulting from thermal regeneration cycles when the material is in operation

25. Zeochem Z3-04 and Z4-04 For Natural Gas Dehydration
Zeochem Steaming Test simulates regeneration conditions in use, by testing for Hydrothermal Stability
Both CO2 capacity and ethane capacity are measured before and after steaming to measure how much pore shrinkage takes place
Exceptional stability vs Competitive products
Very Consistent Quality from lot to lot

26. Hydrothermal Stability Ethane Adsorption
Sample Designation
Ethane Adsorption Capacity New ml / g
Ethane Adsorption Capacity Aged ml / g
Comp "A" 3A 1/16" European nat gas reference Sample 1
24.5
0.2
Comp "A" 3A 1/16" European nat gas reference Sample 2
36.0
Z mm
Standard 4A grade
44.8
1.4
Z mm
Natural Gas Grade
42-45
10-20

27. Zeochem Z3-04 For Natural Gas Dehydration
X-Ray powder diffraction
elemental analysis
scanning electron microscopy
kinetic measurement [MTZ measurement ]
hydrothermal stability test
bulk density [g/l]
under- and oversize [max. 5 %]
attrition [%]
crush strength [kp]
residual water [%]
CO2 adsorption [%]

28. Zeochem Z3-04 Cost Savings 1
Beaded molecular sieve has a number of cost advantages over pelletted or extruded products. The following table shows these differences in terms of the OPERATING COSTS per year.
It does NOT include the extra earnings resulting from the less frequent shut-downs or from better product recovery.

29. Zeochem Z3-04 Cost Savings 2
Pressure drop losses are a hidden cost.
The cost of running a compressor is considerable.
Standard costs are available showing that for every 1000 Nm3 per hour of gas and every mbar of pressure drop the cost of compression is 2.42 US dollars

30. Zeochem Z3-04 Cost Savings 3
The cost of regeneration is one of heat costs (athough the gas may also be lost).
Zeochem has a high density product: around 10% higher than extruded product, which means that the number of cycles per year is also 10% lower
Hence a saving in heat costs can be calculated. Standard cost assumed is 6.83 US dollar per 1000 kWh

31. Zeochem Z3-04 Cost Savings 4
Basis
Natural Gas Dehydrator operating with 2 beds on a 16 hour cycle, regeneration with dry product gas
Flow Rate
Temperature
Pressure
Molecular Weight
Heat Capacity
Adsorption time
Service Lifetime
Regeneration time
Inlet Water
Outlet Dew Point
200,000 Nm3/hr
25°C
32 bara 20
2.4 kJ / kg/ °C
8 hours
minimum 3 years, but projected 4 years for Z3-04
5 hours heating at a temperature of 280°C
saturated at plant conditions ie 193 kg / hr
< -100°C

32. Zeochem Z3-04 Cost Savings 5
Adsorbent Type / Operating parameters
Zeochem Z3-04 beads mm
Typical 3A 1/8 inch extrudates
Bed Internal Diameter mm
Bed Height mm
Weight of adsorbent pr bed kg
Pressure Drop mbar
Adsorbent unit cost US$ per kg
Regeneration Flow Nm3 / hr at 32 bar
Furnace Requirement kWh
3100
3000
16500
300
2.50
10666
1831
3400
451
10872
1866
Cost Summary in US$ per year
3 year life
Adsorbent Cost in US$ per year
Pressure drop cost at 2.42 US$ / mbar / 1000 Nm3/hr per year
Heating cost at 6.83 US$ / 1000 kWh
27500
152944
68469
230150
69778
Total Costs in US$ per year
248913
327428

33. Zeochem Z3-04 Cost Savings 6
The previous table clearly shows that the yearly pressure drop and heating costs alone can far outweigh the initial costs of the molecular sieve, over the assumed 3 year service lifetime. There is the added benefit of an extra year lifetime available with Z3-04.
IN THIS CASE SAVINGS TOTAL
78,515 US$ PER YEAR OF OPERATION

34. NATURAL GAS DEHYDRATION MIDDLE EAST EXAMPLE
Compositions
Feed Gas
Regeneration Gas C1
60.3 %
91.8 % C2
20.7 %
7.2 % C3
12.4 %
0.3 %
i-C4
1.0 %
n-C4
3.2 %
i-C5
0.7 %
C6+
0.5 % N2
0.4 %
Mol Wt.
25.25
17.21

35. NATURAL GAS DEHYDRATION MIDDLE EAST EXAMPLE
Three Column System
Two columns adsorbing and one on regeneration
Split Bed
2/3 large bead and 1/3 small bead

36. NATURAL GAS DEHYDRATION MIDDLE EAST EXAMPLE
Modules 1 and 3
Column
D142 A
D142 B
D142 C
D342 A
D342 B
D342 C
Break Through Slope °F/min
1.667
1.318
2.33
1.289
1.20
1.378
Time To Break hr
29.9
28.2
28.3
29.8
MTZ Length mm
310
418
235
395
364
369
Ave. Flow Rate mmscfd / col
190
Pressure psig
455
470
Temperature °F 69
66.5
Moisture Content lb /mmscf
43.94
39.53
Pressure drop psid
12.7
12.3
13.4
Calc. Pressure Drop psid
10.48
10.01
Water Adsorbed lb
10402
9811
9845
9358
9327
Actual Water Capacity %
13.7
12.9
12.4
Predicted Water Capacity %
11.90

37. NATURAL GAS DEHYDRATION MIDDLE EAST EXAMPLE

39. Zeochem Z3-04 For Natural Gas Dehydration – References
Zeochem Z3-04 is in service in many plants including major natural gas companies in
The Middle East
Europe
Asia
North America
South America

40. Zeochem Z3-04 For Natural Gas Dehydration
A PARTNERSHIP WITH OUR CUSTOMERS
HIGH QUALITY
LOWER COSTS
PEACE OF MIND
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