Emerson's Patrick Truesdale presents steps to improve energy efficiency in ethylene production processes.

1. Reconciling Mass and Energy Balances in an Ethylene Complex Patrick Truesdale Senior Consultant Industry Solution Group Emerson Process Management November 11, 2009 Nashville, TN

4. Ethylene Plants: Configuration and Complexity Ref: T. Ren, University of Utrecht and BASF 2000

5. Ethylene Plants: Estimated Capacities – 1 Jan. 2009 Ref: OGJ 30 July 2009

6. Ethylene Plants: Global Distribution and Age In 1980’s Plants were typically ca 300kta Now Mega Crackers > 1,000kta Predominantly Greenfield Predominantly Brownfield

7. Hydrocarbon/Measurement Timeline

10. Meet the New Engineers and Operators! We may dress funny but we’re computer geeks!

12. Where are losses? Why Important? Open Inventory + Receipts – Shipments – Closing Inventory = Gain/Loss Gain/Loss = Accountable + Unaccountable Leaks Theft Flare Coke Fuel Produced Fuel Consumed

13. Energy Efficiency

14. Step 1: Define Process Boundaries C2 Hydrogenation Cold Box C3 Hydrogenation Cracked Gas Compressor Quench Tower Cracking Furnaces Hydrogen 1%-9% Methane 6%-28% (fuel) Ethylene 23%-76% Ethane 3%-20% (recycle) Propylene 3%-16% Propane 2%-10% C4s 2%-9% Gasoline <1%-35% Steam & Waste Heat Steam Steam Feeds (60%) Ethane (C2) Propane (C3) Butane (C4) Naphtha (C5 – C12) Gas Oil (C10 – C15) Fuel Gas Drying and Chilling Ethylene and Propylene Refrigeration Systems Steam (40%) Quench Water Circuit Oil / Tar Fractionator Fuel Oil Tar C2 Splitter Depropanizer C3 Splitter Debutanizer Deethanizer Demethanizer 800-900 ° C 1.5 bar 350 ° C 1.5 bar 30 ° C 1.5 bar 10 ° C 1.5 bar -100 ° C 32 bar 20 ° C 5 bar 50 ° C 2 bar -10 ° C 30 bar 10 ° C 10 bar -10 ° C 30 bar 75 ° C 30 bar 70 ° C 8 bar 90 ° C 5 bar 45 ° C 5 bar 45 ° C 16 bar 35 ° C 16 bar -20 ° C 20 bar -30 ° C 20 bar -6 ° C 20 bar 80 ° C 1.5 bar Fired Heater Distillation Cryogenic Distillation Hydrogenation Reactor Turbo Compressor

15. Shore Ship Consumers Raw Material Production & Supply Ethylene Complex Load Port Logistics Unload Port Ship Shore Shore Ship Transportation Loss Load Port Transportation Loss Shore Unload Port Ship $ “The Cash Register” Step 2: Identify Custody Transfer Boundaries? BOL BOL

16. Step 3: Design Mass and Energy Balances Receipts Shipments Intercompany Inventories Tank-to-tank transfers Unit-to-tank transfers Process Nodes Tank-to-unit transfers Losses Consumption

18. Select Technology Required Pressure Drop Accuracy Low Maintenance Slurry Flows Viscosity Independent Flow meter Type Non- Conductive Fluids Non- Intrusive Turbine Positive Displacement Coriolis Magmeter Differential Pressure Vortex Good Marginal Poor Ultrasonic

20. Tank Gauge Measurement Capabilities 1 API ± 3/16&quot; (4 mm) 2 PTB, Germany 3 NMi, Netherlands 4 OIML, International 5 TankRadar

22. Do errors always get even out? Think again! NO: Statistical sum of several measurement errors equals: Square Root of the sum of Square of the errors When adding several errors, sum can not be zero!

24. Example Heat Balance Envelope 100 Kg 9.242 MJ 91423.7 J/Kg 100 Kg 1.068 MJ 10683.6 J/Kg 100 Kg 4.217 MJ 42170 J/Kg 100 Kg 12.291 MJ 122.9 KJ/Kg 100 Kg 3.871 MJ 38706 J/Kg 100 Kg 11.944 MJ 11944.6 J/Kg

25. Example Heat Balance Envelope 100 Kg 9.242 MJ 91423.7 J/Kg 100 Kg 1.068 MJ 10683.6 J/Kg 100 Kg 4.217 MJ 42170 J/Kg 100 Kg 12.291 MJ 122.9 KJ/Kg 100 Kg 3.871 MJ 38706 J/Kg 100 Kg 11.944 MJ 11944.6 J/Kg

26. Step 5: Define Business Process Period End Cutoff Data Gross Error Detection and Diagnostics Trial Balancing Resolution or Reconciliation Checking Modifications Adjustments Complex Configuration Models Measurements Movements Lab Data Meter Tickets Surveyor Documents Tank Inventories Utilities Results Generation Manual Input Automatic Data Collection Reconciled Balances, Yield, Loss and Inventory Reporting Production Management Data Base Integrate with Other Systems (SCM, SAP, LP, etc)

27. Step 7: Identify KPI Reporting

28. KPI Dashboard

30. Get Benefits: Operational Excellence Impact Up to 7.9% Operational Improvement by Impacting… +3% +2.4% -1.3% -1% -0.2%

31. Measurement Losses: What is it worth? Assume 0.2% Loss Reduction 93% 1150$/t 500$/t

35. Case 2: Measurement Errors vs Economic Losses Control Variable Objective Function (e.g. Profit) Operating Region Deviations are often corrected with high-cost sub-optimum correction ! Potential lost profit from inaccurate measurements.

36. Trading Benefits A Gulf Coast refiner switched a cargo of crude with just one-and-a-half hours of supply left in inventory . Without very close coordination between trading and operations, the $8 million profit opportunity would have been lost. Hydrocarbon Processing

37. Trading Example Trader Gulf Coast Complex Okay, if you can agree with the shipper to deliver 8 hours earlier, then we will have a four hour safety margin and the trade is agreed. Hold on while we check:: - Current inventory - Maintenance Plan - Agreed Receipts and Shipments and rerun the schedule to check the impact on stocks and cash flow. Delivery 8 hours earlier is agreed. We make $3,000,000 and we extend our credit line by 3 days. GREAT, is there anything I can do to help with a backup strategy? We have an excellent opportunity to purchase a cargo of feed stock. Can we take it?

40. Thank You