Paper Mill Repowering with Gasification

Transcription

1 Frontline Gasifier Benson, MN Paper Mill Repowering with Gasification Jerod Smeenk 2011 TAPPI IBBC Conference March 14,

2 Repowering Options Looking Inside the Box Kiln replace fossil fuel with liquid or gaseous renewable fuel Existing resources tall oil New sources include pyrolysis oils or producer gas derived from biomass or waste feedstocks Steam generation replace worn out or low efficiency wood boilers with new, high efficiency steam generation equipment Electricity - displace utility power (likely fossil based) with internally generated renewable power in a power only or combined heat and power approach with steam generation 2

3 Repowering Options Looking Outside the Box Electricity use existing infrastructure to generate renewable power Green-Brown Arbitrage value of REC s? Long term PPA with local utility Biorefinery Shift some or all of the mill s products to fuels and chemicals Leverage existing brown field site with established feedstock supply chain, feedstock site infrastructure, regulatory permits, labor pool, and utility interconnects 3

4 Why Repower? Reduce operating costs and exposure to fuels market volatility Utilize local resources to keep energy dollars close to home Reduce carbon footprint Improve public image by being renewable Diversify product portfolio to mitigate risks associated with single product/industry 4

5 Gasification in P&P Industry Over thirty year history of P&P applications Gasification of mill residue and wood for thermal energy Gasification of black liquor for syngas production and chemical recovery 5

6 What is Gasification? Direct Gasification (Air or Oxygen) Indirect Gasification (Heat Exchange) Also, CO H CH 2 4, CO 2, H 2 O 6

7 Gasification is a Thermochemical Process Combustion Fuel + Excess Air Heat + Hot Exhaust Gas + Ash Direct Gasification Fuel + Limited Air Producer Gas + Heat + Char-ash + Tar Fuel + Limited Oxygen Syngas + Heat + Char-ash + Tar Indirect Gasification and Pyrolysis Fuel + Heat Syngas or Pyrolysis Gas + Char-ash + Tar 7

8 When Should Gasification Be Considered? Wood feedstock MSW-derived feedstock Kiln fuel X X Boiler fuel X Kiln & boiler fuel X X Biorefinery X X 8

9 Frontline Gasification System BIOMASS METERING HOPPER BIOMASS DRYER LOCK HOPPER AIR PRODUCER GAS (H 2, CO, CH 4, H 2 O, CO 2, C X H Y, N 2 ) GASIFIER 1 st STAGE COOLING (heated air to gasifier) 2 nd STAGE COOLING (steam generation or hot air to biomass dryer LIME KILN BOILER BAGHOUSE FILTER CHAR-ASH COOLING, DEDUSTING, LOAD-OUT 9

10 Feasibility Study Repower objectives include Reduce operating expenses in the power island by lower fuel cost and higher conversion efficiencies Decrease their carbon footprint through eliminating use of fossil fuels Improve public relations by having a totally green product Learn about gasification for possible future biofuel applications 10

11 Repower using producer gas Lime recovery kiln Replace existing multi-fuel kiln burner (fuel oil, natural gas, tall oil) with a new burner that could use all those fuels AND producer gas New burner required because the low energy density of producer gas requires large volumes of gas High pressure package boiler Generate power in an underutilized condensing steam turbine Tie into mill steam header to facilitate scheduled maintenance of mill boiler fleet 11

12 Lime Kiln Firing Producer Gas Flame temperature adequate flame temp Heat transfer producer gas flame emissivity slightly less than natural gas Gas volume with 15% MC feedstock, estimated 13% increase in flue gas flow rate Increase in kiln flue gas was deemed manageable with existing ESP and induced draft fan Biomass dryer required to condition feedstock to 15% MC target 12

13 Lime Kiln Firing Producer Gas Particulate in producer gas If present can contribute to emissivity for radiant heat transfer in the kiln, but we weren t convinced it was essential to successful heat transfer If present will result in lime contamination Quality of mill products may require high purity lime in which case lime purge is expensive and prohibitive 13

14 Package Boiler Firing on Producer Gas Particulate free producer gas enables use of standard gas package boilers Low maintenance removal of contaminants from the producer gas eliminates boiler fouling and corrosion Fuel flexibility able to operate on producer gas or natural gas High availability fuel flexibility provides very high on-stream time 14

15 Package Boiler Firing on Producer Gas Low emissions proper combustion to minimize formation of NO x emissions that otherwise would result from combustion of ammonia (NH 3 ) in the producer gas 15

16 Project Economic Results Detailed economic analysis to establish CAPEX, OPEX, and projected IRR Breakdown of CAPEX ~ 44% for gasifier system ~ 36% for biomass dryer ~ 9% for wood yard upgrades ~ 11% for package boiler and trim 16

17 Project Economic Results Project IRR fell a few points short of the internal hurdle rate; included ITC to reduce CAPEX The mill is still interested in performing the project but need to have financial fundamentals change Increased fossil fuel costs Lower cost feedstocks Reduced CAPEX 17

18 Repower Economics 35% Effect of Feedstock Cost and Fuel Gas Value on ROI Annual Cash Flow, % of Invested Capital 30% 25% 20% 15% 10% 5% 0% $3.00 $4.00 $5.00 $6.00 $7.00 Biomass Fuel Cost $2/MMBtu $3/MMBtu $4/MMBtu $5/MMBtu 400 MMBH Biomass Gasifier, Including Dryer Fuel Gas Value, $/MMBtu 18

19 Repower Economics 10 Effect of Feedstock Cost and Fuel Gas Value on ROI 9 Simple payback, years Biomass Fuel Cost $0/MMBtu $1/MMBtu $2/MMBtu $3/MMBtu 3 2 $3.00 $4.00 $5.00 $6.00 $7.00 Fuel Gas Value, $/MMBtu 400 MMBH Biomass Gasifier, Including Dryer 19

20 Summary Natural gas and feedstock prices dictate plant economics Biomass is uniquely suited among renewables for providing low carbon gaseous fuels True gasification provides the opportunity to utilize existing gas appliances (gas integration) and provide instant natural gas backup to protect plant operation Energy dollars directed to local economy instead of foreign countries Biorefinery optionality for biofuels production

21 Frontline BioEnergy, LLC 1421 S. Bell Avenue, Suite 105 Ames, IA