2007 Chevron and John Zink Company, LLC

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Arline Randall
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2 Session 10 Thursday, December 7, 8:00-9:30 NOx Reduction Implementation Technology Plant-wide NOx Reduction Strategies: Chevron John Zink Experience Ed Shepherd, Chevron (Richmond, CA) Jim Seebold,, retired from Chevron (Richmond, CA) Chuck Baukal, John Zink (Tulsa, OK)

3 Factors to Consider Existing & future permitted NOx levels Existing equipment emissions performance Capital & operating costs Complexity & reliability Emission credits costs Planned equipment shutdowns Future production levels Future process modifications Space availability & requirements Timing Heating equipment loading (base vs. peaking) Environmental considerations of any new equipment

4 NOx Reduction Efficiency Technology Approximate Reduction (%) Approximate Emissions (lb/mmbtu) Standard Burners Low-NOx Burners (LNB) Ultra-Low-NOx-Burners (ULNB) Flue Gas Recirculation Selective Noncatalytic Reduction (SNCR) Selective Catalytic Reduction (SCR) Base Case 60% 80 95% 55% 40% 90 97% Source: M. Bradford et al., Controlling NOx Emissions Part 1, Chem. Eng. Prog., Vol. 98, No. 3, pp , 2002.

5 NOx Reduction in Process Heaters Control Technology Controlled Emissions Percent Reduction Low-NOx Burners lb/10 6 Btu 25-65* Staged Air Lances Not Available Ammonia Injection Not Available Urea Injection + Low NOx Burner Not Available Selective Catalytic Reduction ppm Selective Catalytic Reduction + Low NOx Burner ppm *Reductions of up to 90% have been demonstrated. Source: J. Bluestein, NOx Controls for Gas-Fired Industrial Boilers & Combustion Equipment: A Survey of Practices, Gas Research Institute (Chicago), Report GRI-92/0374, 1992.

6 NOx Reduction Cost Effectiveness ($/ton) SCR System SCR + Low -NOx Burners Next Generation Low - NOx Burners Fuel Dilution on Conventional Burners Current Generation Low NOx Burners $/Ton NOx Reduced Source: J. McAdams et al., Minimize NOx emissions cost-effectively, Hydrocarbon Processing, Vol. 80, No. 6, pp , 2001.

7 NOx Reduction Retrofits Cost Impact of Reduction Mandates Cost 50 0 Major Processing Complex NOx Reduction Projects Cost vs. Percent Reduction Least-Cost Technology Mix % % NOx Reduction Shape of curve confirmed in every capital project we have either done or studied Significant difference between 65% and 85% That kind of difference roughly DOUBLES the cost Paying public & stockholders like the lower cost better

8 Most cost-effective approach to plant-wide NOx reduction benefits both consuming public & corporate shareholders Negotiate a bubble rule on emissions from the entire processing complex Try to negotiate a cost-effective overall reduction under the bubble Control major sources to the max leaving smaller sources alone Favor ultra low NOx burner retrofits avoiding the proliferation of smaller SCRs But provide at least one huge SCR on a major source (e.g., boiler house, steam methane reformer) as a dial control on total emissions under the bubble

9 What we would LIKE to do! What we would like NOT to do!

10 Why we don t like SCRs too much... It s only money! 35-mm slide conversion coming!

11 Selective Catalytic Reduction (SCR) System Flue Gas Ammonia in carrier gas Flue gas containing NOX from another process Catalyst

12 OK, fine, you may prefer to do burners, but which SCRs make the most sense? Really BIG ones The bigger the better They re all highly effective But the bigger they are the more costeffective they become!

13 Build really BIG SCRs! (mmbtu)1/ Firing Rat e, mmbt u/ hr

14 Chevron Richmond s NOx Project Highlights Huge Savings Accrued to the Shareholders by Inspiring & Supporting the Development of Extremely Low-NOx Burners Savings No SCR at the boiler house!..... No SCR at crude unit F1100/F1160! No SCR at hydrogen reformer F355!... CapEx OpEx ~$10m ~$2m/yr ~$10m ~$10m ~$2m/yr ~$2m/yr ~$30m ~$6m/yr Intense collaboration with burner suppliers Crude unit burners installed on-the-run Favorable margins NO shutdown contributed to refinery profitability

15 Chevron Richmond #4 Crude Unit Ultra Low NOx Burner Retrofit

16 Ultra low NOx burners installed on the run!

17 180 ppm 0 ppm

18 180 ppm 14 ppm

19 SCR Reduction (92%) at a Burner Price! For process heating you DON T need a selective catalytic reduction flue gas treatment plant but you really DO need burners so why not super-low NOx burners Before 180 ppm After 14 ppm

20 Relative NOx Emissions The Trick? Deep penetration into the low-btu regime whilst maintaining flame stability! Region of Stoichiometric Combustion ULTRA LEAN PREMIX Diffusion Flame Premix Flame Flammability Limit Design burner to operate in this region Fuel rich combustion Fuel lean combustion

21 On the other hand, you ll still need at least one monster SCR whether you like it or not!

22 Free-standing stack lift with monster low-temperature SCR in the background (on one of two SMR furnaces) illustrates why we don t like SCRs too much Be Safe or... I ll KILL you!

23 Pre-lift Safety Talk

24 The other SMR furnace got ultra low NOx burners! 3 Cell Terrace Wall Steam Methane Reformer 228 burners

25 Chevron Richmond Boiler House Note hills that would have been the central duct supports for two monster SCRs...

26 Poor Man s SCR: Fuel Conditioning! Fuel Induced Recirculation (FIR) or Fuel Dilution Reaction rate limited! Reduce flame temperature, NOx, ppm PERF Fuel Dilution 95 Constant Firing Rate reduce NOx! 80 Cool Fuel! Ain t science wunaful? Nitrogen in Fuel Gas, vol% 30 35

27 The BIG Idea: Deep penetration into the low-btu regime while still maintaining flame stability! It s all about making a low-btu fuel Premixed FIR (Fuel Induced Recirculation) Example One way to do it secondary air flue gas primary air fuel gas flame

28 ~ 93% NOx Reduction!

29 #4 Boiler Sub-10 ppm Demonstration ~ 98% NOx Reduction! DIAL-A-NOX in action!!!

31 Recent photograph of an expert alertly seeking breakthrough solutions... Questions?

C C A. Combustion Components Associates, Inc.

C C A. Combustion Components Associates, Inc. C C A Combustion Components Associates, Inc. www.cca-inc.net About CCA CCA is a global provider of combustion control technologies to reduce NOx, particulate matter (PM), unburned carbon and CO emissions