Emission Reduction Efforts at UGP

Transcription

1 Emission Reduction Efforts at UGP Near-Zero Flaring Strategy Hijji A. Al-Alawi /UGP/SAGO November 5, 2008 Doha Copyright 2008, Saudi Aramco. All rights reserved.

2 Outline Introduction Environmental/Operation Concerns Flare Minimization efforts Flare Gas Recovery (FGR) Concept Design selection criteria Challenges Design basis Base case Alternative design Benefits of FGRS Conclusion

3 Introduction Flares are safety devices designed to protect public and facilities from release of unburned gas to the atmosphere Flares are designed to efficiently destroy waste gas generated in the plant during normal operation and process upset Performance parameters of flares includes smokeless capacity, thermal radiation and noise level Historically, flares emission was not a parameter of interest due to relatively low energy price and difficulty to measurer waste gas

4 Introduction (cont..) Flaring and gas venting contribute significant to the global emission of GHG s (~ 150 billion M^3/year) Flare reduction projects offer long term emission reduction at chemical and petrochemical industries Roadmap was developed by the Corporate Flare task Team to minimize daily flaring from new and existing company facilities Flare gas recovery becomes a standard to recover gas from company facilities. Upgrade selection of existing flare system is a function of flare size and daily flaring from existing facility

5 Operation and Environmental Concerns Flares are over-sized for day-today flaring Flares are utility type Smokey at all flaring rates Premature failure of Tips, Pilots & Igniters

6 Operation and Environmental Concerns (Cont..) Flare valves are low class (high passing rate) Frequent valve overhauling Waste of valuable product

7 Waste gas minimization efforts Upgraded all existing flare valves to class (V)- tight shut off Managed purge gas flaring Improved operation practice Installed flare meters

8 Separator Compressor WATER SEAL Flare

9 FGR Design Selection Criteria Proven technology Safe integration with the plant operation Ability to process varying stream compositions Competitive capital and operating costs Power consumption Simple operation and easy start-up Operation and maintenance reliability Turndown efficiency

10 Design Challenges Difficulty to use recovered gas where energy demand is expected to be steady Low heating value ( burners must be design properly) Not easy to re-processed (off spec. product) Relatively low pressure (compression is need if gas has to be processed) Project cannot be justified on economic due to; Relatively low fuel gas price No CO2 tax credit Relatively low daily flaring rate

11 UGP Design Basis FGR system capacity of 8.0 MMSCFD Recovered gas shall be routed to the front end of the plant FGR recovery shall be designed with 50% turndown ratio Liquid seal shall break at =/>3.5 psig backpressure N 2 shall be used for purging the flare system

12 Project Scope (Base case) Multistage compression: 1 st stage: Two stage blowers Inter-stage cooler Inlet separator 2 nd stage: Oil injected compressors Design features Minimum equipment in the FGR package No liquid circulation and no effluent

13 Alternative Designs Liquid Ring Compression (LRC) Liquid Ring Compressor Water after cooler Liquid Separator Oil flooded screw compressor Design features Proven technology Safe operation (no metal to metal contact) Can handle dirt with the recovered gas stream Relatively low operating temperature

14 Benefits of FGR Promote Kingdom s & Company s image through protecting the environment Provides economic & environmental incentives over other options; Reduce emissions of CO 2, SO X & NO X Revenue enhancement Improves Maintenance and Operation reliability of flares (~ 400%) Qualify for CO 2 Tax credit It has positive return on investment

15 Conclusion FGR design will greatly improve the air quality Reduce give-away waste gas and improve the flare operation reliability It will have very positive public attention to the facility and the company

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