SYNGAS CONDITIONING UNIT FEASIBILITY CASE STUDY: COAL-TO-LIQUIDS

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SYNGAS CONDITIONING UNIT FEASIBILITY CASE STUDY: COAL-TO-LIQUIDS Case Study: #0953616GB/H Process Information Disclaimer Information contained in this publication or as otherwise supplied to Users is believed to be accurate and correct at time of going to press, and is given in good faith, but it is for the User to satisfy itself of the suitability of the Product for its own particular purpose. GBHE gives no warranty as to the fitness of the Product for any particular purpose and any implied warranty or condition (statutory or otherwise) is excluded except to the extent that exclusion is prevented by law. GBHE accepts no liability for loss, damage or personnel injury caused or resulting from reliance on this information. Freedom under Patent, Copyright and Designs cannot be assumed.



COAL-TO-LIQUIDS FEASIBILITY PROJECT CASE STUDY HT SHIFT REACTOR CATALYST SPECIFICATION Process Specification This process duty specification refers to a Syngas Conditioning Unit which utilizes HT Shift reaction technology on a slip stream of raw gas to produce a recombined gas stream with a H2

:CO ratio of 1.57:1. This is an important consideration as the Shift reactor is not required to minimize CO at outlet, and this specification refers to the expected performance that can be achieved in a single stage reactor scheme.

The Syngas Conditioning Unit is part of a proposed coal-to-liquids complex in which synthesis gas is produced by gasification of coal for downstream processing in a Fischer Tropsch reactor and Hydrocracker unit. Basis of Design It is anticipated that a number of parallel trains will be required, in view of the large gas flow rate considered. For the purposes of this preliminary design, a maximum allowable catalyst bed diameter of 4.5m should be assumed. The catalyst vendor will advise the number of parallel trains required on this basis. Our client has requested that we evaluate two competing options for integration of the HT Shift reactor into the overall coal-to-liquids process scheme. Two alternative HT Shift feedstock options are therefore under consideration, (A and B) as defined below (Sour and Sweet shift respectively):



End of Run Conditions

A B Inlet Temperature (o 191 C) 196 Inlet Pressure (bara) 40 40 Inlet Flow (kmol/h) 159,208 151,439 Feedstock Composition

Component Mol % Mol % Hydrogen Carbon Monoxide Carbon Dioxide Nitrogen Methane Ethane Ammonia H2S HCN COS Water

13.00 33.66 2.70 0.50 0.04 - 0.01 0.07 0.01 0.01 50.0

13.75 35.60 0.10 0.50 0.05 - - - - - 50.0



Catalyst Performance Specification

END of Run CO Slip (Dry basis)

10% max

10% max

Available Pressure Drop (bar)

0.25 (1) 0.25 (1)

Run Life (years) 2 2 1. Vessel nozzle to nozzle The feedstock specification provided refers to end of run conditions based on the following assumed approach to equilibrium: Feedstock A (Sour Shift): 40°C approach to equilibrium at EOR Feedstock B (Sweet Shift): 24°C approach to equilibrium at EOR At SOR conditions, the flowrate of raw gas that bypasses the Shift reactor will be increased to ensure that the H2

:CO ratio of the recombined gas can be maintained at 1.57:1.

Data requested from GBHE Catalyst type/size Catalyst bed volume and ordered volume Recommended bed dimensions and number of parallel trains required Maximum gas flowrate through each bed Outlet gas composition and pressure drop at start and end of run conditions Performance Guarantees Catalyst Cost



CTL FEASIBILITY CASE STUDY - RESULTS FEEDSTOCK A – SOUR SHIFT CATALYST: VIG SGS201 Preliminary calculations have shown that the Shift Sections must consist of several parallel trains. A number of 5 trains results in reasonable Bed Volumes. Please note all Flow Rates stated below are per train. The following Cases were considered: Case: Client Original GBHE Required Feed Flow Rate (kmol/h, wet): 31841.80 40579.28 Feed Flow Rate (Nm3 713697.6 /h, wet): 909543.9 Feed Flow Rate (kmol/h, dry): 15920.80 Feed Flow Rate (Nm3 356848.8 /h, dry): Steam Flow Rate (kmol/h): 15920.80 26802.69 Steam Flow Rate (Nm3 356848.8 /h): 600755.6 Steam/CO Ratio (mol/mol: 1.485 2.500 Steam/Dry Gas Ratio (mol/mol): 1.000 1.684 Catalyst Bed Diameter D (m): 4.50 Feed Composition (mol%, dry): Hydrogen Carbon Monoxide Carbon Dioxide Nitrogen Methane NH3 H2S HCN COS TOTAL

26.00 67.32 5.40 1.00 0.08 0.02 0.14 0.02 0.02 (= 200 ppmv) 100.00

Inerts (mol%, dry) 1.28 H2S/COS Ratio (mol/mol): 7.00 Inlet Operating Pressure (bara): 40 (= 38.987 barg) Interbed Cooling: Heat Exchanger Inlet Operating Temperature (o 300 C) Exit CO Slip (mol%, dry) 10.00



The Client’s original design is not acceptable due to both the Steam/CO Ratio and the Steam/Dry Gas Ratio specified being too low. For an Inlet Operating Pressure First Reactor of 40 bara and an Inlet CO Level exceeding 40 mol% (dry) a Steam/CO Ratio of at least 2.500 mol/mol is required, which then results in a Steam/Dry Gas Ratio of 1.684 mol/mol, which is acceptable. These values for the Steam/Dry Gas Ratio and the Steam/CO Ratio are required to avoid the risk of methanation. The recommended steam level will not cause any desulfiding of the catalyst at the specified inlet H2S Level.

Case: GBHE EOR GBHE SOR Feed Flow Rate (kmol/h, wet): 40579.28 Feed Flow Rate (Nm3 909543.9 /h, wet): Feed Flow Rate (kmol/h, dry): 15920.80 Feed Flow Rate (Nm3 356848.8 /h, dry): Expected Exit Operating Temperature (o

495.0 C):

510.0

Expected Catalyst Bed Pressure Drop (bar):

4.70 (2years) 3.61 (2 years)

Guaranteed Catalyst Life (Years):

2 N.A.

Gas Exit Composition (mol%, dry): Inerts: H2 CO CO2 TOTAL

0.84 51.35 10.00 37.81 100.00

0.82 52.67 7.02 39.49 100.00

Exit Steam: Dry Gas Ratio (mol/mol):

0.7646 0.7168

Guaranteed Maximum CO Slip (mol%, dry):

10.00 N.A.

Expected Maximum CO Slip (mol%, dry):

N.A. 7.02

Catalyst Bed Volume (m3 87.80 ): Catalyst Bed Diameter D (m): 4.50 Catalyst Bed Height H (m): 5.52 Number of Parallel Trains Required (-):

5

Amount of Catalyst to be Ordered (m3

5 x 1.03 x 87.80 = 452.2 ):



FEEDSTOCK B – SWEET SHIFT: VULCAN SERIES VSG-F101 Preliminary calculations showed that the original case (provided by client) produced an Exit Operating Temperature of the first reactor of around 560o

C, which is far too high. As such the following two bed option was considered.

Case GBHE Design Feed Flow Rate (kmol/h, wet): 36345.36 Feed Flow Rate (Nm3 814644.9 /h, wet): Minimum Acceptable Catalyst Bed Volume for Each Reactor (m3

101.8

) (Order: 2 x 5 x 1.03 x 101.8 = 1049)

Catalyst Bed Diameter D (m): 4.5 Catalyst Bed Height H (m): 6.40 H/D 1.42 Feed Flow Rate (kmol/h, dry): 15143.90 Steam Flow Rate (kmol/h): 21201.46 Steam/Dry Gas Ratio (mol/mol): 1.40 Feed Composition (mol%, dry): Hydrogen Carbon Monoxide Carbon Dioxide Nitrogen Methane NH3 H2S HCN COS TOTAL

27.50 71.20 0.20 1.00 0.10 0.00 0.00 0.00 0.00 100.00

Case B First Reactor EOR Bed 1 Expected Exit Operating Temperature (o

531.4 C):


1.4 (2 years)

Guaranteed Catalyst Life (Years): 2



Gas Exit Composition (mol%, dry): CH4 H2 CO CO2 N2 TOTAL

0.07 49.34 19.61 30.27 0.70 100.00

Exit Steam: Dry Gas Ratio (mol/mol): 0.677 Guaranteed Maximum CO Slip (mol%, dry):

19.61

Bed 2 Optimized Inlet Operating Temperature (o

385.5 C):

Expected Exit Operating Temperature (o

422.3 C):


1.5 (2 years)

Guaranteed Catalyst Life (years): 2 Gas Exit Composition (mol%, dry): CH4 H2 CO CO2 N2 TOTAL

0.06 54.78 6.77 37.76 0.62 100.00

Exit Steam: Dry Gas Ratio (mol/mol): 0.497 Guaranteed Maximum CO Slip (mol%, dry):

6.77

Case B First Reactor SOR Bed 1 Expected Exit Operating Temperature (o

541.5 C):


1.4 (SOR)


0.06 53.51 9.78 36.01 0.64 100.00

Exit Steam: Dry Gas Ratio (mol/mol): 0.539



Expected Maximum CO Slip (mol%, dry): 9.78 Bed 2 Optimized Inlet Operating Temperature (o

364.7 C):


397.3 C):


1.3 (SOR)


0.06 55.70 4.57 39.04 0.61 100.00

Exit Steam: Dry Gas Ratio (mol/mol): 0.466 Expected Maximum CO Slip (mol%, dry): 4.57 The only way to reduce the Catalyst Bed Pressure Drops for both sour and sweet shift will be to increase the Catalyst Bed Diameter. The choice of a larger Maximum Allowable Catalyst Bed Diameter may imply local manufacture of the reactors. One way to reduce the Catalyst Bed Volumes required would be to use radial reactors. At the same time GBHE could then consider the use of mini catalyst, because the Catalyst Bed Pressure Drops in radial reactors tend to be lower than in the corresponding axial reactors. The use of mini catalyst in axial reactors is clearly out of the question because of the unacceptably high Catalyst Bed Pressure Drops that would result.



APPENDIX



HTS Section (Sweet Shift) Starting Point: Preliminary calculations have shown that the HTS Section (Sweet Shift) must consist of several parallel trains and that due to equilibrium restrictions each train needs to have 2 HTS reactors in series called HT1 and HT2, respectively (with intercooling) in order to be able to achieve the required CO Slip. A number of 5 trains results in reasonable Bed Volumes. In this document only the Sweet Shift option will be considered (Case B). Please note all Flow Rates stated below are per train (unless specifically mentioned otherwise). The following Cases were considered: 1/Cases Considered Type of Shift Life Inlet

Operating Pressure First Reactor (bara)

Inlet Operating Temperature First Reactor (oC)

Case B SOR

Sweet Shift SOR Expected 40 310*

Case B EOR

Sweet Shift 2 Years Guaranteed

40 310*

*In order to minimize the Exit Operating Temperature of the first HTS reactor the minimum allowable Inlet Operating Temperature was chosen for this reactor. The Inlet Operating Inlet Temperature of the second reactor was optimized, because in the second reactor the exotherm was much less severe than in the first HTS reactor. 2/Catalyst Used: VULCAN SERIES VSG-F101 3/Client Requirements: Required Guaranteed Maximum Catalyst Life (years):

2

Required Guaranteed Maximum CO Slip EOR (i.e. 2 years, mol%, dry):

10.00

Required Guaranteed Total Maximum Catalyst Bed Pressure Drop for Each Train (EOR (bar):

0.25*

Required Maximum Allowable Catalyst Bed Diameter (m):

4.5*



*Preliminary calculations have shown that the Required Guaranteed Total Maximum Catalyst Bed Pressure Drop for Each Train cannot at all be achieved with the Required Maximum Allowable Catalyst Bed Diameter (Unless the Client would accept a ridiculously large number of parallel trains, say 10 to 15, a number of 5 appears to be the maximum number that is still considered acceptable by our Clients in general). A larger Maximum Allowable Catalyst Bed Diameter should be considered. The choice of a larger Maximum Allowable Catalyst Bed Diameter may imply local manufacture of the reactors. 4/Feed Flow Rates per Train and Feed Composition Inlet First Reactor; Minimum Acceptable Catalyst Bed Volume for Each Reactor and Other Reactor Dimensions Case B1* B2 B3 Feed Flow Rate (kmol/h, wet):

30287.80 33316.58 36345.36

Feed Flow Rate (Nm3

678870.7 /h,

wet):

746757.8 814644.9

Minimum Acceptable Catalyst Bed Volume for Each Reactor (m3

84.9

)**:

(Order: 2 x 5 x 1.03 x 84.9 = 874)

93.3 (Order: 2 x 5 x 1.03 x 93.3 = 961)

101.8 (Order: 2 x 5 x 1.03 x 101.8 = 1049)

Catalyst Bed Diameter D (m):

4.50***

Catalyst Bed Height H (m):

5.34 5.87 6.40

H/D (-)****: 1.19 1.30 1.42 Feed Flow Rate (kmol/h, dry):

15143.90

Steam Flow Rate (kmol/h):

15143.90 18172.68 21201.46

Steam/Dry Gas Ratio (mol/mol):

1.00 1.20 1.40



Feed Composition (mol%, dry): Hydrogen Carbon Monoxide Carbon Dioxide Nitrogen Methane NH3 H2S HCN COS TOTAL

27.50 71.20 0.20 1.00 0.10 0.00 0.00 0.00 0.00 100.00

*Case B1 is the original case as submitted by the Client. However, preliminary calculations showed that this original case produced an Exit Operating Temperature of the first reactor of around 560oC, which is far too high. This temperature needs to be brought down to at least 540o

C in accordance with our design rules. The only way to do this is by increasing the Steam/Dry Gas Ratio. This may not be achievable. The Client will probably also have to face considerable material of construction problems/issues in view of the rather demanding temperature regime.

**These Catalyst Bed Volumes were calculated using in accordance with our design rules (Proprietary). *** Required Maximum Allowable Catalyst Bed Diameter. ****The H/D values found are all greater than 0.6 and are therefore acceptable according to our design rules. *****This Inlet CO Level is very high and makes the overall duty very demanding.



Results: The Total Wet Flow Rate throughout each train does not change. For Cases B SOR and B EOR an Initial WGS Activity Factor was chosen (High Temperature Shift Catalyst Activity for Partial Oxidation Plants), Proprietary. Case B1 EOR B2 EOR B3 EOR Bed 1: HT1 (HTS) Expected Exit Operating Temperature (o

559.2 C):

550.8 531.4


0.908 (2 years)

1.148 (2 years)

1.422 (2 years)

Guaranteed Catalyst Life (Years): 2 Gas Exit Composition (mol%, dry): CH4 H2 CO CO2 N2 TOTAL

0.07 51.26 15.08 32.92 0.67 100.00

0.07 51.87 13.65 33.75 0.66 100.00

0.07 49.34 19.61 30.27 0.70 100.00


0.344 0.460 0.677


15.08 13.65 19.61

Reduction Potential (-): 1.515 1.263 1.083 Bed 2: HT2 (HTS) Optimized Inlet Operating Temperature (o

363.4 C):

375.5 385.5


411.5 C):

413.0 422.3


0.872(2 years)

1.161 (2 years)

1.525 (2 years)

Guaranteed Catalyst Life (years): 2 Gas Exit Composition (mol%, dry): CH4 H2 CO CO2 N2 TOTAL

0.06 53.99 8.57 36.71 0.63 100.00

0.06 54.67 7.00 37.63 0.63 100.00

0.06 54.78 6.77 37.76 0.62 100.00


0.269 0.375 0.497




8.57 7.00 6.77

Reduction Potential (-): 1.478 1.224 1.041 Case B1 SOR B2 SOR B3 SOR Bed 1: HT1 (HTS) Expected Exit Operating Temperature (o

559.2 C):

551.3 541.5


0.864 (SOR) 1.103 (SOR) 1.377 (SOR)


0.07 51.27 15.05 32.93 0.67 100.00

0.07 52.54 12.07 34.67 0.65 100.00

0.06 53.51 9.78 36.01 0.64 100.00


0.344 0.440 0.539


15.05 12.07 9.78

Reduction Potential (-): 1.515 1.263 1.083 Bed 2: HT2 (HTS) Optimized Inlet Operating Temperature (o

342.5 C):

355.5 364.7


397.4 C):

398.2 397.3


0.754 (SOR) 1.004 (SOR) 1.303 (SOR)


0.06 54.45 7.47 37.36 0.63 100.00

0.06 55.20 5.72 38.38 0.62 100.00

0.06 55.70 4.57 39.04 0.61 100.00


0.256 0.359 0.466


7.47 5.72 4.57

Reduction Potential (-): 1.483 1.228 1.046



Comments Cases B3 EOR and B3 SOR show an Expected Exit Operating Temperature of around 540o

C. However, the extra steam required has increased the Catalyst Bed Pressure Drops.

A larger Catalyst Bed Diameter will be required to achieve the Required Guaranteed Total Maximum Catalyst Bed Pressure Drop for Each Train. For all Cases the value for the Reduction Potential R is so low (all lower than 1.9), that over-reduction of the HTS can be safely ruled out. Using optimized Operating Inlet Temperatures could only be applied for the second bed, because of the very high exotherm in the first bed. Of course the steam content must always stay below dew point level. Under the current conditions there is no risk of steam condensation (See table below). The Required Guaranteed Maximum CO Slip EOR (2 years) of 10.0 mol% (dry) can be achieved. One way to reduce the Catalyst Bed Volumes required would be to use radial reactors. At the same time we could then consider the use of mini catalyst, because the Catalyst Bed Pressure Drops in radial reactors tend to be lower than in the corresponding axial reactors. The use of mini catalyst in axial reactors is clearly out of the question because of the unacceptably high Catalyst Bed Pressure Drops that would result. Case Inlet

Operating Temperature HT1 (o

Inlet Dew Point HT1 (

C) o

Inlet Operating Temperature HT2 (

C) o

Inlet Dew Point HT2 (

C) oC)

B1 EOR 310 212.4 363.4 179.8 B1 SOR 212.4 342.5 179.9 B2 EOR 216.8 375.5 188.8 B2 SOR 216.8 355.5 187.5 B3 EOR 220.3 385.5 199.9 B3 SOR 220.3 364.7 193.4



Sour Shift Section Starting Point: Preliminary calculations have shown that the Sour Shift Section must consist of several parallel trains. A number of 5 trains results in reasonable Bed Volumes. In this document only the Sour Shift option will be considered (Case A). Please note all Flow Rates stated below are per train (unless specifically mentioned otherwise). The following Cases were considered: 1/Cases Considered Type of

Shift Life Inlet Operating

Pressure (bara) Inlet Operating Temperature (oC)

Case A SOR

Sour Shift SOR Expected 40 300

Case A EOR

Sour Shift 2 Years Guaranteed

40 300

2/Catalyst Used: VULCAN Series VIG SGS201. The use of this catalyst is allowed here, because the Inlet Operating Pressure is only 40 bara. 3/Client Requirements: Required Guaranteed Maximum Catalyst Life (years): 2 Required Guaranteed Maximum CO Slip EOR (i.e. 2 years, mol%, dry):

10.00

Required Guaranteed Total Maximum Catalyst Bed Pressure Drop for Each Train EOR (bar):

0.25*

Required Maximum Allowable Catalyst Bed Diameter (m): 4.5* *Preliminary calculations have shown that the Required Guaranteed Total Maximum Catalyst Bed Pressure Drop for Each Train cannot at all be achieved with the Required Maximum Allowable Catalyst Bed Diameter (Unless the Client would accept a ridiculously large number of parallel trains, say 10 to 15, a number of 5 appears to be the maximum number that is still considered acceptable by our Clients in general). A larger Maximum Allowable Catalyst Bed Diameter should be considered. The choice of a larger Maximum Allowable Catalyst Bed Diameter may imply local manufacture of the reactors.



4/Oxygen and Olefins. There are no oxygen or olefins present in the feed, which would have resulted in an additional exotherm and a change in the composition of the feed. 5/HCN The catalyst hydrogenates 90% of the HCN present in the feed. 6/NH3 The NH3 Level present in the feed will not affect the performance of the catalyst. 7/Arsine No mention is made of the presence of arsine. Arsine is a severe catalyst poison. In view of the fact that coal is the starting point in this process it would be wise to double-check whether there is really no arsine whatsoever present in the feed of the Sour Shift Section. 8/Input Data Sour Shift Unit Case: A1* A2** Feed Flow Rate (kmol/h, wet): 31841.80 40579.28 Feed Flow Rate (Nm3 713697.6 /h, wet): 909543.9 Feed Flow Rate (kmol/h, dry): 15920.80 Feed Flow Rate (Nm3 356848.8 /h, dry): Steam Flow Rate (kmol/h): 15920.80 26802.69 Steam Flow Rate (Nm3 356848.8 /h): 600755.6 Steam/CO Ratio (mol/mol: 1.485 2.500 Steam/Dry Gas Ratio (mol/mol): 1.000 1.684 Catalyst Bed Diameter D (m): 4.50***



Feed Composition (mol%, dry): Hydrogen Carbon Monoxide Carbon Dioxide Nitrogen Methane NH3 H2S HCN COS TOTAL

26.00 67.32 5.40 1.00 0.08 0.02 0.14 0.02 0.02 (= 200 ppmv) 100.00

Inerts (mol%, dry)****: 1.28 H2S/COS Ratio (mol/mol): 7.00 Inlet Operating Pressure (bara): 40 (= 38.987 barg) Interbed Cooling: Heat Exchanger Inlet Operating Temperature (o 300 C)*****: Exit CO Slip (mol%, dry) 10.00 *Case A1 is the original case as submitted by the Client. Please note that both the Steam/CO Ratio and the Steam/Dry Gas Ratio specified by the Client are too low. For an Inlet Operating Pressure First Reactor of 40 bara and an Inlet CO Level exceeding 40 mol% (dry) a Steam/CO Ratio of at least 2.500 mol/mol is required, which then results in a Steam/Dry Gas Ratio of 1.684 mol/mol, which is acceptable. These values for the Steam/Dry Gas Ratio and the Steam/CO Ratio are required to avoid the risk of methanation. The recommended steam level will not cause any desulfiding of the catalyst at the specified inlet H2S Level (it is borderline though). **Case A2 was actually used in the calculations. *** Required Maximum Allowable Catalyst Bed Diameter. ****Inerts (mol%, dry) is defined as 100 – CO Level (mol%, dry) – CO2 Level (mol%, dry) – H2 Level (mol%, dry). *****Preliminary calculations demonstrated that for this duty only 1 bed per train is required.



10/Activity (Proprietary) Results: The Total Wet Flow Rate throughout each train does not change. Downflow and axial reactors have been assumed. The details are given below: Case: A2 EOR A2 SOR Feed Flow Rate (kmol/h, wet): 40579.28 Feed Flow Rate (Nm3 909543.9 /h, wet): Feed Flow Rate (kmol/h, dry): 15920.80 Feed Flow Rate (Nm3 356848.8 /h, dry): Expected Exit Operating Temperature (o

495.0 C):

510.0


0.90* (2 years)

0.75 (2 years)

Guaranteed Catalyst Life (Years): 2 N.A. Gas Exit Composition (mol%, dry): Inerts***: H2 CO CO2 TOTAL

0.84 51.35 10.00 37.81 100.00

0.82 52.67 7.02 39.49 100.00


0.7646 0.7168


10.00 N.A.


N.A. 7.02

Catalyst Bed Volume (m3 87.80 ): Catalyst Bed Diameter D (m): 4.50 Catalyst Bed Height H (m): 5.52 Number of Parallel Trains Required (-):

5

Amount of Catalyst to be Ordered (m3

5 x 1.03 x 87.80 = 452.2 ):



*The only way to reduce the Catalyst Bed Pressure Drop will be to increase the Catalyst Bed Diameter. The choice of a larger Maximum Allowable Catalyst Bed Diameter may imply local manufacture of the reactors Comments Cases A2 EOR and A2 SOR show an Expected Exit Operating Temperature of around 500o

C, which is acceptable.

A larger Catalyst Bed Diameter will be required to achieve the Required Guaranteed Total Maximum Catalyst Bed Pressure Drop for Each Train. A normal value would have been 0.1 – 0.2 bar. The values found here are far too high. Of course the steam content must always stay below dew point level. Under the current conditions there is no risk of steam condensation, because the dew point at the inlet is only 224.1o

C.

The Required Guaranteed Maximum CO Slip EOR (2 years) of 10.0 mol% (dry) can be achieved. One way to reduce the Catalyst Bed Volumes required would be to use radial reactors. At the same time we could then consider the use of mini catalyst, because the Catalyst Bed Pressure Drops in radial reactors tend to be lower than in the corresponding axial reactors. The use of mini catalyst in axial reactors is clearly out of the question because of the unacceptably high Catalyst Bed Pressure Drops that would result. Desulfiding of the catalyst is not expected to occur. However, margins of only 16 (Case A2 EOR) and 5 (A2 SOR) oC, respectively, were calculated, whereas we would normally recommend a margin of 25o

C. If the H2S Inlet Level drops there will certainly be a desulfiding problem. It is borderline.

A Catalyst Bed Height of 5.52 m is acceptable. Linear velocities above 0.35 m/s have never been applied.



For Cases A2 EOR and A2 SOR, respectively, linear velocities of 1.04 and 1.05 m/s, respectively, were found. These linear velocities are 1.35 (Case A2 EOR) and 2.19 (Case A2 SOR) times the fluidization threshold. In down flow mode the linear velocity must be below 1.5 times the fluidization threshold to prevent milling of catalyst at the top of the bed. The only way to reduce the linear velocity is by choosing a larger Catalyst Bed Diameter. At an Inlet Operating Pressure of 40 bara GBHE would have recommended a Wet Space Velocity of 8132 h-1. In the above 2 Cases a Wet Space Velocity of 10539 h-1

was found. Again this is pretty borderline (well worse, really). On the other hand GBHE may have been a bit too cautious here. Again the only way to improve this situation is by choosing a larger Catalyst Bed Diameter.

SYNGAS CONDITIONING UNIT FEASIBILITY CASE STUDY: COAL-TO-LIQUIDS

Technology

Transcript of SYNGAS CONDITIONING UNIT FEASIBILITY CASE STUDY: COAL-TO-LIQUIDS