1. Black Liquor Gasification Design Project GP Wauna Gasifier Design Justin Aldrich, Adam Cooper, Khoa Hua, Jim Jollimore Mill Integration Sean Noste, Steve Ross, John Salvatier, Peter Siedenburg, Nilar Thein-chen Environmental Cody Hargrove, Sonha Pham, Claire Schairbaum, Larissa Zuk Economics Darrow Conley, Ryan McMahon, Vinh Nguyen, Suzy Quach

2. Agenda Gasifier Design Mill Integration Environmental Economics

3. High Temperature Gasification Image Source: http://www.eng.utah.edu/~whitty/blackliquor/colloquium2003/pdfs_handouts/5.6.Lindblom-Chemrec_Handout.pdfhttp://www.eng.utah.edu/~whitty/blackliquor/colloquium2003/pdfs_handouts/5.6.Lindblom-Chemrec_Handout.pdf

4. High Temperature Gasification Syngas Properties: Heating Value Sulfur Low Temp Gasifier High Temp Gasifier Natural Gas Higher Heating Value (MJ/kg) 20.959.3242.5 Low Temp Gasifier High Temp Gasifier H 2 S in Syngas (%mol) 2.2501.737 H 2 S in Syngas values from Larson 2003. Gasifier values from Larson 2003. Natural gas value from Wikipedia.

5. High Temperature Gasification Effect on Causticization Load Reliability Weyerhauser, New Bern, Chemrec Booster 1996. Low Temp Gasifier High Temp Gasifier High Temp Booster Sulfur (%)~90%~50%~15%

6. Low Temperature: Pros Low Temperature Better return on energy Ease of getting chemicals back H 2 S is in a gaseous form Proven system that is currently running Norampac Trenton Ontario Use heat to produce needed steam and electricity

7. Low Temperature: Con Need additional equipment to recover Chemicals Air scrubbers to recover SO 2 Higher initial cost than High Temp ~32% higher initial startup cost

8. Trim Cooler Raw Syngas, 40 ° C 2 Stage Gas Cooler or Heat Exchanger O 2 Plant High Temp Gasifier 1000 ° C 35 bar 165 TPD GL Cond HX Selexol Absorber 40 °C ~30 bar Selexol Stripper 40 °C ~30 bar To Lime Kiln BL Solids @ 67% Solids Air, 20 ° C Vent Cooled Green Liquor 132 ° C Cooling Water 200 ° C 35 bar Raw Syngas Raw Syngas, 122 ° C Clean Syngas 40 ° C ~30 Bar LP Steam WL Scrubber H 2 S and CO 2 High Sulfidity White Liquor 95% O 2, 20 ° C LP Steam? Cooling Water? White Liquor

9. Raw Syngas, 40 ° C Raw Syngas, 600 ° C Trim Cooler Selexol Absorber 40 °C ~25 bar Selexol Stripper 40 °C ~25 bar Clean Syngas 40 ° C LP Steam WL Scrubber H 2 S and CO 2 High Sulfidity White Liquor Or Green Liquor White Liquor Low Temp Gasifier 650 ° C 1.2 bar 165 TPD Low Pressure Superheater BL Solids @ 67% Solids Mix Tank & Filter Na 2 CO 3 Dregs Clean Syngas PC Heater Flue Gas HX Steam Superheated Steam Heat Exchanger Cooling Water LP Steam or Warm Water Compressor

10. Claus Plant Converts H 2 S gas into elemental sulfur Has two parts: thermal stage and catalytic stages Operates at moderate temperatures (340° C to 200° C) Uses Titanium Dioxide or Alumina as a catalyst 94 to 97% efficiency depending on the number of catalytic stages 2H 2 S + O 2 → S 2 +2H 2 O

11. Liquor Scrubbing Product gas stream contains CO 2 and H 2 S Scrubbing CO 2 generates Na 2 CO 3 which increase the lime kiln load Use the NaOH in the liquor to regain the pulping chemical Na 2 S 85% efficiency at sulfur recovery H 2 S + 2NaOH → Na 2 S + 2H 2 O

12. CrystaSulf Uses SO 2 to convert H 2 S into elemental sulfur Operates at lower temperatures (170 °C) Claims to be more economical for 0.2 to 30 LTPD H 2 S flows Uses hydrocarbons and amines as catalysts 2H 2 S + SO 2 → ⅜ S 8 + 2H 2 O + 33kcal/gmole

13. Mill Integration: Objective Energy and Mass Balance on Process Create WinGEMS Model Determine Impact of Gasifier Effect of Burning Syngas in Lime Kiln Transportation of Syngas

14. Schematic from Wauna Mill

15. Steam Balance Calculation Steam UsageKPPH Evaporators83 Concentrator39 PM 1,236 PM 532 PM 6,723 Bleach Plant90 Recaust18 Kamyr54 M&D Sawd38 Total413 Steam ProducedKPPH Recovery Boiler431 Power Boiler91 Fluidized Bed Boiler106 Total628 Total From PPT557

16. Calculation Comparison According to Mill Our Calculations Extra Steam (KPPH) 50144 Black Liquor, Redirected (Mlbs/hr of black liquor solids) 13.838.51

17. WinGEMS Full Mill 4.2 gal total/min 34 cons% 177.2 gal total/min 36 cons% 302.2 gal total/min 64 %mass 1653 gal total/min 10 cons% 16.1 mt/hr 31 psig Pulp yield: 47.4 % 1800 gal total/min 1577.1 gal total/min 16.5 %mass Black liquor 542 gal total/min Slaker Lime Kiln Mud washer White liquor clarifier 1003 od st/day 1302 gal total/min 0.0002 g/l as NaOH EA 2116 od st/day 581.3 gal total/min CondensateBL spillsTall oil Makeup chemicals Air Green liquor clarifier Smelt Filtrate 687 gal total/min Weak black liquor EA: 107 g/l as NaOH Sulfidity: 28 % 581 gal total/min 724 gal total/min TTA: 130 g/l as NaOH Grits Flue gas To scrubber Spent acid ScrubberSpills Wood chips CaO Make-Up Brownstock washers Strong black liquor Digester flash steam Evaporators Shower water Fresh water makeup Mud washer and filter filtrates Kraft Pulp Mill and Recovery Flash tank Flash tank Chip presteam Wash zone CONTINUOUS DIGESTER Fresh shower water White liquor Unbleached pulp Recovery Boiler SDT Weak wash to SDT Lime Air Lost lime dust Weak wash Clarified white liquor Fuel Flue gas Makeup NaOH Makeup chemicals to mix tank White liquor to digesters Clarified green liquor Dregs Steam vents Recovered sulfur Stream 59 flow is manipulated to achieve a TTA of 130 g/l as NaOH in the green liquor, stream 50. Created By Pacific Simulation

18. WinGEMS Modification Wood chips 420 od st/day 0 gal total/min 0 cons% 0 gal total/min 0 cons% 0 gal total/min 0 %mass 0 gal total/min 0 cons% 0 mt/hr -14.7 psig Pulp yield: 0 % 1800 gal total/min 0 gal total/min 0 %mass Black liquor 626 gal total/min Slaker Lime Kiln Mud washer White liquor clarifier 0 od st/day 0 gal total/min 0 g/l as NaOH EA 1000 od st/day 0 gal total/min CondensateBL spillsTall oil Makeup chemicals Air Green liquor clarifier Smelt Filtrate 1300 gal total/min Weak black liquor EA: 0 g/l as NaOH Sulfidity: 0 % 0 gal total/min TTA: 0 g/l as NaOH Grits Flue gas To scrubber Spent acid ScrubberSpills Wood chips CaO Make-Up Brownstock washers Strong black liquor Digester flash steam Evaporators Shower water Fresh water makeup Mud washer and filter filtrates Kraft Pulp Mill and Recovery Flash tank Flash tank Chip presteam Wash zone CONTINUOUS DIGESTER Fresh shower water White liquor Unbleached pulp Recovery Boiler SDT Weak wash to SDT Lime Air Lost lime dust Weak wash Clarified white liquor Fuel Flue gas Makeup NaOH Makeup chemicals to mix tank White liquor to digesters Clarified green liquor Dregs Steam vents Recovered sulfur Stream 59 flow is manipulated to achieve a TTA of 130 g/l as NaOH in the green liquor, stream 50.

19. Burning Syngas in Lime Kiln Combustion in kiln and TADs Sulfur needs to be scrubbed from syngas Send scrubbed sulfur to kiln for recovery Combustion in kiln only No need to scrub sulfur from syngas Potential increase in ball and ring formation from sulfur

20. Transportation of Syngas Hydrogen is main component in syngas Amount of carbon in steel decreases when in contact with hydrogen creating pockets Methane forms in pockets inside the steel causing steel to become brittle Choice of material is very important

21. Mill Integration: Conclusion Modified WinGEMs Simulation Adequately Future comparison of High and Low Temp Using WinGEMS Comparing chemical balances Steam balance Load on lime kiln Optimal use of syngas

22. Air Emissions Black liquor gasifier system should have low air emissions including: CO 2 (Carbon Dioxide) SO 2 (Sulfur Dioxide) NO X (Nitride Oxides) VOCs (volatile organic compounds) TRS emissions (Total Reduced Sulfur) A lot of contaminant removal is required to recover the pulping chemicals from the gas

23. Air Emissions: High Temp vs. Low Temp Figure 1. Emissions estimated for low temperature and high temperature gasifiers. The values were calculated using a 353 day operating schedule per year. Source: Larson, E.D., & Consonni, S., & Katofsky, R.E. (2003). A Cost-Benefit Assessment of Biomass Gasification Power Generation in the Pulp and Paper Industry.

24. Air Emissions: Mill Limits Figure 2. These are emission standards for the Georgia-Pacific mill in Wauna. Source: Oregon Department of Environmental Quality. (2005). Oregon Title V Operating Permit (Permit Number 04-0004). Portland, OR.

25. Water Emissions & Usage Two water issues associated with the addition of gasifier: Water Usage Thermal Pollution Secondary treatment facility has a maximum capacity of 42 million gal/day. In 2007, GP Wauna averaged 27.3 million gal/day. There is no way the gasifier will cause the mill to increase its water consumption by 15 million gal/day.

26. Thermal Pollution Maximum allowable discharge temperature from secondary treatment plant is 20 °C. In 2007, GP Wauna’s secondary treatment was fed waste water at a temperature of 29.3 °C. The addition of 7.2 million gpd at 40 °C from the gasifier could potentially raise the temperature of the discharge waste water stream by 2 °C.

27. Syngas Exposure Carbon Monoxide – PEL 50 ppm EXTREMELY toxic Flammable Hydrogen – No PEL Not toxic; excessive exposure may lead to asphyxiation EXTREMELY flammable Carbon Dioxide – PEL 5,000 ppm Toxic

28. Syngas Storage Store in well ventilated areas. Store where temperature is less than 50 °C Remove sparking and ignition hazards Stainless steel is satisfactory Risk of embrittlement with hydrogen Syngas is not pure hydrogen, so embrittlement risk is minimal

29. Natural Gas Usage Natural gas (Therms/year) Total CO 2 Emissions (metric tons/year) Lim Kiln4,029,600 3,641 PM 1,21,825,000 1,649 PM 54,197,500 3,792 PM 68,030,000 7,255 PM 79,125,000 8,244 Bed Boiler1,314,000 1,187 LVHC36,500 33 Total28,557,600 25,802

30. Raw Syngas Component ComponentVolume % CO13.1 H2H2 13.7 CH 4 0.75 H2OH2O63.7 CO 2 7.6 H2SH2S0.67 COS0.03 N2N2 0.14 Ar0.37 ComponentVolume % H2OH2O63.7 H2H2 13.7 CO13.1 CO 2 7.6 CH 4 0.75 H2SH2S0.67 Ar0.37 N2N2 0.14 COS0.03

31. Raw Syngas Produced BL enter Gasifer (dry lbs/hour) Raw Syngas (kg/year) Raw Syngas (Therms/year) Natural Gas Needed (Therms/year) High Temp1380084,738,7157,485,92321,071,677 Low Temp13800110,549,82621,952,7856,604,815

32. CO 2 Produced Syngas (Therms/year) Syngas (kg/year) CO (kg/year) CO 2 (kg/year) CO 2 (metric tons/year) Natural Gas High 21,071,67752,307,34129,889,90919,038,15919,038 Syngas High 7,485,92318,582,702 2,415,7512,950,9802,951 Total21,989 Natural Gas Low 6,604,81516,395,481 9,368,846 5,967,4185,967 Syngas Low 1,952,785 54,494,5617,084,2938,653,8758,654 Total14,621 Natural Gas only 28,557,60070,890,042 40,508,59625,801,653 25,802 Total25,802

33. Social Impact Benefit Improve the economics Greenhouse gases reduction Lower net emission of CO 2 Possible downside Water thermal discharge

34. Economics: Agenda Major Equipment Summary of Calculation Capital Cost Analysis Cost Reduction Conclusions

35. Major Equipment and Components Gasifier Air Separation Unit Sulfur Recovery Unit (SRU) Selexol/Rectisol Green Liquor Scrubber Gas Cooler (Heat Exchangers)

36. Summary of Calculation Capital cost adapted from Eric Larson’s A Cost-Benefit Assessment of Biomass Gasification Power Generation in the Pulp and Paper Industry Adjustment made with High Temp 2002$ inflated to 2008$ Scaled to Wauna specifications using 6-tenths factor 2576.8 tons BL/day  165.6 tons BL/day Lang factor used to estimate indirect costs from direct costs

37. Capital Cost Analysis Cost From Larson Article$ Million Direct CostLow TempHigh Temp Gasifier Island and Green Liquor Filter9.68011.607 Air Separation Unit7.935 Process gas handling6.997 Gas clean up and sulfur recovery9.7133.188 Auxiliaries1.321 Total Direct27.71122.729 Indirect cost Construction Indirect5.6071.821 Sales Tax, Customs, Duties0.134 Engineering5.8601.812 Contingency3.6182.525 Escalation Spare Parts1.2991.239 Licensing Fee0.081 Owner's Costs2.9142.513 Total Indirect19.38010.043 Total Installed47.09032.772

38. Cost Reduction Analysis Low TempHigh Temp Flow Syngas (kg/s)23.7624.24 Heating value (MJ/kg)20.959.32 NG Heating Value (MJ/kg)42.50 Syngas Energy Production (Therm/Day)407,632185,006 NG replacement (Therm/Day)9,591.554,353.18 Savings by using Syngas ($ Million/Yr)3.0811.398 Total Installed ($ Million)87.96666.300 ROI (%)6.544.27

39. Conclusions Low Temp Gasification Higher up front cost Higher ROI Better at replacing natural gas with Syngas High Temp Gasification Lower up front cost Lower ROI Consult with design team Stability against Natural Gas Increase

40. Questions