A Cost-Benefit Assessment of Gasification-Based Biorefining in the Kraft Pulp and Paper Industry

Abstract

Production of liquid fuels and chemicals via gasification of kraft black liquor and woody residues ("biorefining") has the potential to provide significant economic returns for kraft pulp and paper mills replacing Tomlinson boilers beginning in the 2010-2015 timeframe. Commercialization of gasification technologies is anticipated in this period, and synthesis gas from gasifiers can be converted into liquid fuels using catalytic synthesis technologies that are in most cases already commercially established today in the "gas-to-liquids" industry.These conclusions are supported by detailed analysis carried out in a two-year project co-funded by the American Forest and Paper Association and the Biomass Program of the U.S. Department of Energy. This work assessed the energy, environment, and economic costs and benefits of biorefineries at kraft pulp and paper mills in the United States. Seven detailed biorefinery process designs were developed for a reference freesheet pulp/paper mill in the Southeastern U.S., together with the associated mass/energy balances, air emissions estimates, and capital investment requirements. Commercial ("Nth") plant levels of technology performance and cost were assumed. The biorefineries provide chemical recovery services and co-produce process steam for the mill, some electricity, and one of three liquid fuels: a Fischer-Tropsch synthetic crude oil (which would be refined to vehicle fuels at existing petroleum refineries), dimethyl ether (a diesel engine fuel or LPG substitute), or an ethanol-rich mixed-alcohol product.Compared to installing a new Tomlinson power/recovery system, a biorefinery would require larger capital investment. However, because the biorefinery would have higher energy efficiencies, lower air emissions, and a more diverse product slate (including transportation fuel), the internal rates of return (IRR) on the incremental capital investments would be attractive under many circumstances. For nearly all of the cases examined in the study, the IRR lies between 14% and 18%, assuming a 25-year levelized world oil price of $50/bbl -the US Department of Energy's 2006 reference oil price projection. The IRRs would rise to as high as 35% if positive incremental environmental benefits associated with biorefinery products are monetized (e.g., if an excise tax credit for the liquid fuel is available comparable to the one that exists for ethanol in the United States today). Moreover, if future crude oil prices are higher ($78/bbl levelized price, the US Department of Energy's 2006 high oil price scenario projection, representing an extrapolation of mid-2006 price levels), the calculated IRR exceeds 45% in some cases when environmental attributes are also monetized.In addition to the economic benefits to kraft pulp/paper producers, biorefineries widely implemented at pulp mills in the U.S. would result in nationally-significant liquid fuel production levels, petroleum savings, greenhouse gas emissions reductions, and criteria-pollutant reductions. These are quantified in...

Decarbonizing the pulp and paper industry: A critical and systematic review of sociotechnical developments and policy options

“…Petterson et al [259], conclude that biomass gasification with dimethyl ether production is profitable and an innovative technique to mitigate emissions if CCS is applied. A similar approach was implemented by Larson et al [260]. Their results indicate that the production of dimethyl ether, Fischer-Tropsch or mixed alcohols from BLG and biomass reduces capital investments compared to stand-alone plants and represents a more effective use of biomass.…”

Biorefineries in Kraft pulp mills for biofuels production: A critical review

“…The conventional black liquor recovery cycle works well, but has some disadvantages such as low energy efficiency and risk of explosions if water leaks and comes into contact with molten inorganic material (mostly Na 2 S and Na 2 CO 3 ). [ 91 ] In the BLG technology, concentrated black liquor is gasified in reactors with specific configurations, generating synthesis gas (syngas), mainly composed of H 2 and CO, but also of CO 2 , CH 4 , and other light gases. Gasification also generates coal, ash, and condensable compounds such as tar and oils.…”

“…This fact is important because it makes the amount of white liquor fed to the digester flexible, making it possible to increase the pulp yield. [ 91 ] However, the recovery of part of the sulphur together with the syngas requires greater capacity of the causticizing unit, including the lime kiln. This is because, as a fraction of S 2− ions are extracted from the melt, more Na + ions become available in the solution and react with carbonate ions, increasing the Na 2 CO 3 concentration. …”

Process synthesis and design of integrated biorefinery in pulp and paper industry

“…low electricity generation efficiency and smelt-water explosions (Naqvi et al, 2010). New technologies including black liquor gasification that offer more efficiency and economic benefits has been developed to overcome and replace the conventional recovery boilers more to offer in terms of efficiency and economic benefits (Larson et al, 2006a).…”

“…DMEa, DMEb and DMEc, for optimization. Process information is collected following Larson et al (2006a). In the DME process design, a liquid-phase DME reactor is performed to convert the synthesis gas from the black liquor gasifier.…”