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Cited by 75Thermochemical Biomass Conversion ProcessesForest Biomass Utilization and ManagementAgricultural and Food Sciences

Lifecycle Assessment and Techno-Economic Analysis of Biochar Pellet Production from Forest Residues and Field Application

Open access
Bergman, Richard, Sahoo, Kamalakanta, Englund, Karl, Mousavi-Avval, Seyed Hashem·2022·Energies
DOI 10.3390/en15041559
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Abstract

Biochar produced from low-value forest biomass can provide substantial benefits to ecosystems and mitigate climate change-induced risks such as forest fires. Forest residues from restoration activities and timber harvest and biochar itself are bulky and thus incur high logistic costs, so are considered major bottlenecks for the commercialization of the biochar industry. The objectives of this study were to assess the environmental footprints and techno-economic feasibility of converting forest residues in Pacific Northwest United States into biochar pellets using portable systems followed by delivery of the final product to end-users for land application (dispersion). Two portable systems (Biochar Solutions Incorporated (BSI) and Air Curtain Burner (ACB)) were considered for biochar production. A cradle-to-grave lifecycle assessment (LCA) and a discounted cash flow analysis method were used to quantify the environmental impacts and minimum selling price (MSP) of biochar. The global warming (GW) impact of biochar production through BSI and ACB was estimated to be 306–444, and 750–1016 kgCO₂eq/tonne biochar applied to the field, respectively. The MSP of biochar produced through BSI and ACB was 1674–1909 and 528–1051 USD/tonne biochar applied to the field, respectively. Pelletizing of biochar reduced GW impacts during outbound logistics (~8–20%) but increased emissions during pelletizing (~1–9%). Results show the BSI system was a more viable option in terms of GW impact, whereas the ACB system can produce biochar with lower MSP. The results of the study conclude that the production of biochar pellets through the two portable systems and applied to fields can be both an environmentally beneficial and economically viable option.

AI snapshot

Written from the paper’s full text.

TL;DR

This study assesses cradle-to-grave environmental impacts and techno-economic feasibility of producing biochar pellets from Pacific Northwest forest residues using two portable systems (BSI and ACB) and applying them to soil. BSI has lower global warming impact, while ACB has lower minimum selling price.

Key findings

  • Cradle-to-grave global warming (GW) impact was 306–444 kgCO₂eq/tonne biochar for BSI and 750–1016 kgCO₂eq/tonne biochar for ACB; BSI was the more viable option for GW impact.
  • Minimum selling price (MSP) was 1674–1909 USD/tonne biochar for BSI and 528–1051 USD/tonne biochar for ACB; ACB produced biochar with lower MSP.
  • Pelletizing reduced GW impacts during outbound logistics (~8–20%) but increased emissions during pelletizing (~1–9%); for BSI, pelletizing reduced GW by 37–54 kgCO₂eq/tonne biochar (~9–18%), while for ACB it increased cradle-to-grave GW by 6%, largely due to diesel generator emissions of about 71 kgCO₂eq/tonne biochar.
  • Field application for carbon sequestration reduced GW impacts substantially (by 2–6 times), with overall reductions of 1420–1800 kgCO₂eq/tonne biochar, making the systems carbon-negative.

Methods

  • Cradle-to-grave LCA following ISO 14040/14044, using SimaPro 9.1 and TRACI 2.1, with a functional unit of 1 tonne biochar; eight scenarios varied portable system (BSI vs. ACB), biochar form (bulk vs. pellets), and inclusion/exclusion of forest operations.
  • Primary data came from the Waste to Wisdom project and Schatz Energy Research Center for forest residue harvesting, feedstock preparation, and biochar production; pelletizing data were taken from literature.
  • TEA used a discounted cash flow rate of return model with 10-year project life, 16.5% nominal discount rate, 40% income tax, 300 operating days/year, 16 h/day, and 2021 USD; sensitivity analysis varied input parameters by ±20% for GW impacts and MSP (MSP sensitivity for scenario 4 only).

Limitations

  • The paper does not state a dedicated limitations section.
  • Evident limitations include the geographic focus on five Pacific Northwest US sites and two portable systems; the authors note pulp log availability due to lack of markets may not reflect other regions of the U.S.
  • The analysis relies on assumptions such as 50 km biochar transport, two relocations per year, 80.5% biochar carbon stability over 100 years, mass allocation for forest operations, and sawlogs outside the system boundary; the figures also note annual operating time of 100 days, while the methods state 300 days/year.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.3390/en15041559

Cites

34 of 34 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

7 of 39 cited sources checked · 2 supported · 0 flagged · accuracy not yet measured

  • Premisecitation

    The wide geographic distribution of forest residues usually causes high costs of logistics operations such as collection, loading, transportation, unloading, and storage.

    “Considering the low price of forest residues, they are considered as a potential feedstock for biochar; however, the wide geographic distribution of forest residues usually causes high costs of logistics operations, e.g., collection, loading, transportation, unloading, and storage [4,11,12].”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites [4] Sahoo, 2019, Techno-Economic Analysis of Producing Solid Biofuels and Biochar from Forest Residues Using Portable Systems, Appl. Energy source
    • cites [11] Wright, 2010, Techno-Economic Analysis of Biomass Fast Pyrolysis to Transportation Fuels, Fuel source
    • cites [12] Yazan, 2016, Design of Sustainable Second-Generation Biomass Supply Chains, Biomass Bioenergy source

      Section 2.1 (Harvesting and collection; page unavailable) says dispersed biomass sites require more transport moves and describes negative economic impacts of dispersion. Section 5.2 (page unavailable) also links longer collection distances to higher transportation costs. The paper does not establish that forest residues specifically are widely distributed or that this distribution raises loading, unloading, and storage costs. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
  • Premisecitation

    The high cost of inbound and outbound logistics is one of the main obstacles to the commercialization of the biochar industry and its growth.

    “The high cost of inbound (i.e., biomass) and outbound (i.e., biochar) logistics is one of the main obstacles to the commercialization of the biochar industry and its growth.”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites [4] Sahoo, 2019, Techno-Economic Analysis of Producing Solid Biofuels and Biochar from Forest Residues Using Portable Systems, Appl. Energy source
    • cites [11] Wright, 2010, Techno-Economic Analysis of Biomass Fast Pyrolysis to Transportation Fuels, Fuel source
    • cites [12] Yazan, 2016, Design of Sustainable Second-Generation Biomass Supply Chains, Biomass Bioenergy source

      The Introduction and §2.1 identify costly biomass transport as a barrier to the economic viability of second-generation bioenergy. Section 3.3 includes trucks carrying bio-oil and char, but the paper does not identify outbound biochar logistics as a main obstacle to commercialization or growth of a biochar industry; it studies supply chains in which biochar is a byproduct. (LLM, conf=0.87)

      Experimental — accuracy not yet measured
  • Premisecitation

    Overall, biochar produced through the ACB system had higher carbon fixation compared to that of the BSI system.

    “Overall, biochar produced through the ACB system had higher carbon fixation compared to that of the BSI system.”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [26] Sahoo, 2021, Life-Cycle Assessment and Techno-Economic Analysis of Biochar Produced from Forest Residues Using Portable Systems, Int. J. Life Cycle Assess. source
    • cites [27] Puettmann, 2020, Life Cycle Assessment of Biochar Produced from Forest Residues Using Portable Systems, J. Clean. Prod. source
  • Findingown data

    Among all scenarios analyzed for the BSI system, the second scenario, biochar as bulk including forest operations during logging, had the highest global warming impact of 444 kgCO2eq/tonne of biochar.

    “Among all scenarios analyzed for the BSI system, the second one, i.e., biochar as bulk, including forest operations during logging, had the highest GW (444 kgCO₂eq/tonne of biochar)”
    Quote in the paperSubstantial claim
  • Findingown data

    The MSP of biochar produced through the ACB system was in the range of 528-1051 USD/tonne.

    “The MSP of biochar produced through the ACB system was in the range of 528-1051 USD/tonne.”
    Quote in the paperSubstantial claim
  • Classified as probably not a substantial claim. 9
  • May combine two claims. 30

  • Classified as probably not a substantial claim.

    Premisecitation

    Pelletization has been recently considered as an alternative method for efficient handling and biochar application to soil to reduce the cost of biochar logistics.

    “To reduce the cost of biochar logistics, pelletization has been recently considered as an alternative method for efficient handling and biochar application to soil [16,19].”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [16] Bergman, R.D., Zhang, H., Englund, K., Windell, K., and Gu, H. (2016, January 6–10). Estimating Ghg Emissions from the Manufacturing of Field-Applied Biochar Pellets. Proceedings of the 59th International Convention of Society of Wood Science and Technology, Curitiba, Brazil.
    • cites [19] Bartocci, 2018, Biocarbon pellet production: Optimization of pelletizing process, Chem. Eng. Trans source

      The Introduction says pelletizing charcoal can improve bulk density and transportation and storage costs, supporting the logistics part of the claim. It discusses the pellets as fuel, however, and does not address efficient handling or applying biochar to soil. (LLM, conf=0.86)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    Few studies have evaluated the use of portable systems; however, their main focus is the production of bio-oil as the main product, but not biochar.

    “Few studies have evaluated the use of portable systems; however, their main focus is the production of bio-oil as the main product, but not biochar [20][21][22][23].”
    Quote in the paperSubstantial claim1 of 4 sources checked
    • cites [20] Badger, 2010, Techno-Economic Analysis: Preliminary Assessment of Pyrolysis Oil Production Costs and Material Energy Balance Associated with a Transportable Fast Pyrolysis System, BioResources source
    • cites [21] Chen, 2018, Mobile Autothermal Pyrolysis System for Local Biomass Conversion: Process Simulation and Techno-Economic Analysis, Energy Fuels source
    • cites [22] Mirkouei, 2016, Reducing the Cost and Environmental Impact of Integrated Fixed and Mobile Bio-Oil Refinery Supply Chains, J. Clean. Prod. source
    • cites [23] Polagye, 2007, An Economic Analysis of Bio-Energy Options Using Thinnings from Overstocked Forests, Biomass Bioenergy source

  • May combine two claims.

    Premisecitation

    Through pelletizing, the bulk density of biochar is increased and the material is aggregated, thus reducing logistics costs.

    “Through pelletizing, the bulk density of biochar is increased and the material is aggregated, thus reducing the logistics (i.e., transportation, storage, handling, and field application) costs [16,17].”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [16] Bergman, R.D., Zhang, H., Englund, K., Windell, K., and Gu, H. (2016, January 6–10). Estimating Ghg Emissions from the Manufacturing of Field-Applied Biochar Pellets. Proceedings of the 59th International Convention of Society of Wood Science and Technology, Curitiba, Brazil.
    • cites [17] Riva, 2019, A Study of Densified Biochar as Carbon Source in the Silicon and Ferrosilicon Production, Energy source

      The Introduction says pelletization generally increases density and mechanical durability, helping address losses during handling and transportation. It also discusses minimizing transportation costs, but the paper measures pellet particle density rather than bulk density and does not establish reduced storage or field-application costs; its application is silicon and ferrosilicon production. (LLM, conf=0.86)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    Conversion of forest residues to biochar in pellet form helps capture carbon from the environment and store it in the soil, thus reducing CO2 in the atmosphere, in addition to increasing soil productivity and enhancing soil carbon.

    “Conversion of forest residues to biochar in the pellet form also helps to capture carbon from the environment and store it in the soil, thus reducing CO 2 in the atmosphere, in addition to increasing soil productivity and enhancing soil carbon [2,10].”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [2] Agegnehu, 2017, The Role of Biochar and Biochar-Compost in Improving Soil Quality and Crop Performance: A Review, Appl. Soil Ecol. source
    • cites [10] Jeffery, 2015, The Way Forward in Biochar Research: Targeting Trade-Offs between the Potential Wins, GCB Bioenergy source

      The ‘Climate change mitigation vs. soil fertility’ section says biochar can sequester carbon in soil for extended periods and reports increased soil fertility, though fertility effects are highly variable. It does not establish these benefits specifically for biochar pellets made from forest residues, and it describes climate mitigation as a potential rather than a guaranteed reduction in atmospheric CO₂. (LLM, conf=0.88)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Findingown data

    Pelletizing can reduce the global warming impacts by 37-54 kgCO2eq/tonne of biochar, about 9-18% of cradle-to-grave global warming impacts, mostly due to the logistics of biochar.

    “However, pelletizing can reduce the GW impacts by 37-54 kgCO₂eq/tonne of biochar (~9-18% of cradle-to-grave GW impacts), mostly due to the logistics of biochar.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Forest operation incurred about 84-101 kgCO2eq/tonne of biochar, about 20-25%, towards cradle-to-grave global warming impacts of the BSI system.

    “Forest operation incurred about 84-101 kgCO₂eq/tonne of biochar (~20-25%) towards cradle-to-grave GW impacts of the BSI system.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingnone given

    The productivity or throughput of the ACB system was much larger than the BSI system, thus notably reducing the MSP for the ACB system.

    “Contrarily, the productivity or throughput of the ACB system was much larger than the BSI system, thus notably reducing the MSP for the ACB system.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingreasoning

    Biochar produced with the ACB portable system at near-forest locations showed higher GW impact (2-2.5 times more) compared to the BSI system, with GW emissions from 750 to 1016 kgCO2 eq/tonne biochar applied to the field.

    “Biochar produced with the ACB portable system at near-forest locations showed higher GW impact (2-2.5 times more) compared to the BSI system, with GW emissions from 750 to 1016 kgCO 2 eq/tonne biochar applied to the field (Figure 4).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingreasoning

    About 20-27% (scenarios 1 and 3) and 52-60% (scenarios 2 and 4) of costs were due to feedstocks in scenarios where forest operations were excluded and included, respectively.

    “About 20-27% (scenarios 1 and 3) and 52-60% (scenarios 2 and 4) were due to feedstocks in scenarios where the forest operations were excluded and included, respectively.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    The BSI system produced lower cradle-to-gate GW impacts, but its carbon sequestration was lower due to lower carbon content in biochar for this system.

    “Although the BSI system produced lower cradle-to-gate GW impacts, the carbon sequestration was lower due to lower carbon content in biochar for this system.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingnone given

    Conversion of biochar to pellets and exclusion of forest operations during logging reduced the MSP of biochar in the ACB system.

    “Conversion of biochar to pellets and exclusion of forest operations during logging reduced the MSP of biochar in the ACB system.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Pelletizing of biochar reduced global warming impacts during outbound logistics by about 8-20% but increased emissions during pelletizing by about 1-9%.

    “Pelletizing of biochar reduced GW impacts during outbound logistics (~8-20%) but increased emissions during pelletizing (~1-9%).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingnone given

    The biochar production yield of ACB and BSI systems was estimated to be 35.6 and 126.8 kg biochar/tonne of woody biomass at 21% (wb), respectively.

    “The biochar production yield of ACB and BSI systems was estimated to be 35.6 and 126.8 kg biochar/tonne of woody biomass at 21% (wb), respectively.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    For the BSI system, MSP was lowest in biochar pellet production excluding forest operations during logging and highest in biochar production as bulk including forest operations during logging.

    “and it was lowest in biochar pellet production by considering exclusion of forest operations during logging and highest in biochar production as bulk by considering the inclusion of forest operations during logging (Figure 6).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingreasoning

    The inclusion of forest operations significantly affects the MSP in both BSI and ACB systems; however, the impact of inclusion and exclusion of forest operations in the ACB system was higher than that in the BSI system.

    “Second, the inclusion of forest operations significantly affects the MSP in both BSI and ACB systems; however, the impact of inclusion and exclusion of forest operations in the ACB system was higher than that in the BSI system.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingnone given

    Conversion of biochar to pellets was found to reduce the overall GW impacts and MSP of biochar production.

    “In addition, conversion of biochar to pellets was found to reduce the overall GW impacts and MSP of biochar production.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingreasoning

    The productivity of ACB systems, such as the hourly production capacity of biochar, was much higher (by ~5 times) than the BSI system, thus helping to reduce the cost including capital and operational costs.

    “The productivity of ACB systems, such as the hourly production capacity of biochar, was much higher (by ~5 times) than the BSI system, thus helping to reduce the cost including capital and operational costs.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Converting biochar into pellets may improve total porosity and aeration porosity; thus, its proper balance in the soil can help plant growth.

    “In addition, converting biochar into pellets may improve total porosity and aeration porosity; thus, its proper balance in the soil can help the plant growth [18].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [18] Dumroese, 2011, Pelleted Biochar: Chemical and Physical Properties Show Potential Use as a Substrate in Container Nurseries, Biomass Bioenergy source

  • May combine two claims.

    Premisecitation

    Forest residues usually have low bulk and energy densities but high moisture content, which tends to generate high costs for feedstock transportation, handling, and drying.

    “In addition, forest residues usually have both low bulk and energy densities but high moisture content, which tends to generate a high cost for feedstock transportation, handling, and drying [13,14].”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [13] Parkhurst, 2016, An Energy Analysis Comparing Biomass Torrefaction in Depots to Wind with Natural Gas Combustion for Electricity Generation, Appl. Energy source
    • cites [14] Sahoo, 2018, Economic Analysis of Forest Residues Supply Chain Options to Produce Enhanced-Quality Feedstocks, Biofuels Bioprod. Biorefining source

  • May combine two claims.

    Premisecitation

    Based on literature, after 100 years of land application of biochar, 80.5% of carbon in biochar will remain stable and the remaining 19.5% will be emitted to the atmosphere.

    “Based on the literature [38], it is estimated that after 100 years of land application of biochar, 80.5% of carbon in the biochar will remain stable and the remaining 19.5% will be emitted to the atmosphere.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [38] Budai, A., Zimmerman, A.R., Cowie, A.L., Webber, J.B.W., Singh, B.P., Glaser, B., Masiello, C.A., Andersson, D., Shields, F., and Lehmann, J. (2021, May 15). Biochar Carbon Stability Test Method: An Assessment of Methods to Determine Biochar Carbon Stability. Available online: https://www.biochar-international.org/wp-content/uploads/2018/06/IBI_Report_Biochar_Stability_Test_Method_Final.pdf.

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    Due to the high-quality biochar produced in the ACB system, the carbon storage capacity was much higher, and the net-GW impact was better.

    “Due to the high-quality biochar produced in the ACB system, the carbon storage capacity was much higher, and the net-GW impact was better.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationown data

    The higher GW impact of ACB compared to BSI is mainly due to higher emissions during processing operations and lower biochar yield.

    “This was mainly due to higher emissions during processing operations and lower biochar yield.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Forest residues left on-site increase the risk of wildfires and diseases; the majority of fires result from overstocked forest land.

    “In addition, forest residues left on-site increase the risk of wildfires and diseases; the majority of fires result from overstocked forest land (Dennison et al., 2014;USDOE, 2016).”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites Dennison et al., 2014

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites USDOE, 2016

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Interpretationown data

    The BSI system was a more viable option in terms of global warming impact, whereas the ACB system can produce biochar with lower minimum selling price.

    “Results show the BSI system was a more viable option in terms of GW impact, whereas the ACB system can produce biochar with lower MSP.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    Application of biochar in agricultural lands is considered as a potential solution to prevent loss of fertilizers to water bodies and enhance soil quality by improving soil organic carbon, and hence improving agricultural productivity.

    “Application of biochar in agricultural lands is considered as a potential solution to prevent loss of fertilizers to water bodies and enhance the soil quality by improving the soil organic carbon, and hence improving agricultural productivity [3].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [3] Aller, 2018, Long Term Biochar Effects on Corn Yield, Soil Quality and Profitability in the Us Midwest, Field Crops Res. source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation

    The LCIA was performed using the TRACI 2.1 methodology.

    “LCIA was performed using the Tools for the Reduction and Assessment of Chemical and other Environmental Impacts (TRACI) 2.1 methodology [36].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [36] US-EPA (2012). Tool for the Reduction and Assessment of Chemical and Other Environmental Impacts (Traci)–Traci Version 2.1 User’s Guide.

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Conversion of forest residues to biochar reduces the need for controlled pile and burning of forest residues, which causes air pollution and damages human health.

    “It also reduces the need for controlled pile and burning of forest residues, which causes air pollution and damages human health [9].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [9] Berrill, 2017, Carbon, Harvest Yields, and Residues from Restoration in a Mixed Forest on California’s Coast Range, For. Sci. source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    A sensitivity analysis was performed to estimate the impacts of variations in input parameters on the lifecycle assessment results and financial performance.

    “A sensitivity analysis was performed to estimate the impacts of variations in input parameters on the lifecycle assessment results (i.e., GW impact) and financial performance (i.e., MSP).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationown data

    The production of biochar pellets through the two portable systems and applied to fields can be both an environmentally beneficial and economically viable option.

    “The results of the study conclude that the production of biochar pellets through the two portable systems and applied to fields can be both an environmentally beneficial and economically viable option.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationown data

    The 6% increase from pelletizing was due to emissions associated with high use of fuel in the diesel generator, about 71 kgCO2eq/tonne biochar.

    “This was due to the emissions associated with the high use of fuel in the diesel generator, which was about 71 kgCO2eq/tonne biochar.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Study design and conductcitation

    The LCA was conducted by following the ISO 14040 and ISO 14044 standards to quantify the environmental impacts of biochar production systems.

    “LCA was conducted by following the ISO 14040 and ISO 14044 standards [31,32] to quantify the environmental impacts of biochar production systems.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [31] ISO (2006). Environmental Management: Life Cycle Assessment; Principles and Framework, International Organization for Standardization.

      Not checked in the free run.

    • cites [32] ISO (2006). Environmental Management: Life Cycle Assessments: Requirements and Guidelines, International Standardization Organization.

      Not checked in the free run.

  • May combine two claims.

    Interpretationown data

    The BSI system was revealed to be a more viable option in terms of GW impact, whereas the ACB system can produce biochar with lower MSP.

    “Thus, the BSI system was revealed to be a more viable option in terms of GW impact, whereas the ACB system can produce biochar with lower MSP.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    From previous studies, the MSP of biochar production has been reported to be 838-1504 USD/tonne [41], and 774-1256 USD/tonne [42], depending on temperature, conversion rates, feedstock type, and price.

    “From previous studies, the MSP of biochar production has been reported to be 838-1504 USD/tonne [41], and 774-1256 USD/tonne [42], depending on temperature, conversion rates, feedstock type, and price.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [41] Campbell, 2018, Financial Viability of Biofuel and Biochar Production from Forest Biomass in the Face of Market Price Volatility and Uncertainty, Appl. Energy source
    • cites [42] Cheng, 2020, Slow Pyrolysis as a Platform for Negative Emissions Technology: An Integration of Machine Learning Models, Life Cycle Assessment, and Economic Analysis, Energy Convers. Manag. source

  • Classified as probably not a substantial claim.

    Interpretationreasoning

    Considering the vast area of forests requiring restoration, the BSI system would be considered the best option given its lower GW profile, costs, and MSP.

    “Considering the vast area of forests requiring restoration, the BSI system would be considered the best option given its lower GW profile, costs, and MSP.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    These costs can be offset by incorporating United States Department of Agriculture Conservation Stewardship Program practices (e.g., E384135X).

    “However, these costs can be offset by incorporating United States Department of Agriculture Conservation Stewardship Program practices (e.g., E384135X).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    The State of Washington has a financial incentive of 12,000 USD/ha [43], which would result in negative MSPs [26] for both BSI and ACB systems.

    “For example, the State of Washington has a financial incentive of 12,000 USD/ha [43], which would result in negative MSPs [26] for both BSI and ACB systems.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [43] USDA-NRCS (2019). Conservation Enhancement Activity, E384135z.

      Not checked in the free run.

    • cites [26] Sahoo, 2021, Life-Cycle Assessment and Techno-Economic Analysis of Biochar Produced from Forest Residues Using Portable Systems, Int. J. Life Cycle Assess. source
36 of 36

  • The paper relies on this without support.

    Biochar is often a dry powdery material that is difficult to handle and efficiently disperse.

    “Biochar is often a dry powdery material that is difficult to handle and efficiently disperse.”

  • The paper relies on this without support.

    The ACB system can process biomass with a wide range of moisture content.

    “In addition, ACB can process biomass with a wide range of moisture content.”

  • The authors state this as an assumption.

    All labile carbon and a certain part of recalcitrant carbon in biochar will degrade within a 100-year time-frame.

    “This study considered that all labile carbon and a certain part of recalcitrant carbon in biochar will degrade within a 100-year time-frame [37].”

  • The authors state this as an assumption.

    In this study, biochar pellets are assumed to be transported for further distances.

    “as assumed in this study”

  • The paper relies on this without support.

    Biochar provides long-term storage for carbon that originated from trees pulling carbon dioxide from the atmosphere; when biochar is added to the soil, carbon sinks are formed and carbon sequestration occurs.

    “Furthermore, biochar can provide long-term storage for carbon that originated from trees pulling carbon dioxide from the atmosphere; thus, when biochar is added to the soil, carbon sinks, artificial reservoirs for accumulation of carbon dioxide, are formed and carbon sequestration occurs.”

  • The paper relies on this without support.

    There are several other environmental benefits of making biochar and applying it to the field, including increasing soil quality and productivity.

    “In addition, there are several other environmental benefits of making biochar and applying it to the field, which include increasing soil quality and productivity.”
6 of 6

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • ACB feedstock costs are substantial when forest operations are excluded, despite a stated zero feedstock price

    Major

    The results assign 20-27% of costs to feedstocks in ACB scenarios 1 and 3, which exclude forest operations. The logistics-cost section says ACB feedstock costs zero under that exclusion, and the methods exclude ACB feedstock transport and preprocessing.

  • Final recommendation attributes lower MSP to BSI instead of ACB

    Major

    The final recommendation calls BSI the lower-MSP option, contradicting the paper's reported MSP ranges and its preceding conclusion that ACB has the lower MSP.

  • Economic figures use 100 operating days despite a 300-day financial assumption

    Major

    The financial analysis assumes 300 operating days annually, but the caption for the BSI annual-cost and MSP figure says 100 days. The ACB economic figure carries the same 100-day note.

  • ACB pelletizing additions do not sum to the stated operating-cost increase

    Minor

    The three ACB additions shown in Table 6 total USD 54,406 per year, rather than the USD 53,364 added to its total operating cost.

    Reported 53364 · recomputed 54406

  • Outbound transport distances differ between LCA and cost calculations

    Minor

    The lifecycle inventory uses a 50 km trip to the application site, whereas the outbound logistics cost assumes 160 km one-way. The paper presents both for delivery of biochar without identifying them as different scenarios.

  • Conclusion says pelletizing lowers overall GW impacts, but ACB pelletizing raises them

    Minor

    The conclusion applies a reduction in overall GW impacts to biochar pelletizing, while the results explicitly report an increase for the ACB system.

6 of 6

Cites

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Authors
Bergman, R., Sahoo, K., Englund, K., & Mousavi-Avval, S. H.
Affiliations
  • Forest Products Laboratory (US)
  • University of Wisconsin–Madison (US)
  • Washington State University (US)
  • Forest Products Laboratory, United States Forest Service, 1 Gifford Pinchot Drive, Madison, WI 53726, USA
Corresponding author
Bergman, Richard
ORCID
Venue
Energies
Publisher
MDPI AG
Published
2022-02-20
Volume
15
Issue
4
Pages
1559
ISSN
1996-1073 (ISSN-L)
DOI
10.3390/en15041559
OpenAlex
W4213068390
Semantic Scholar
b5a4703ea85d34fb22baf59fe29f71f47f0c9e1e
Cited by
75
References
34
Citations by year
2026: 28 · 2025: 23 · 2024: 12 · 2023: 8 · 2022: 4
FWCI
3.18
Type
journal article
Language
en
Open access
Licence
Locations
  • Energies (publishedVersion, cc-by)
  • RePEc: Research Papers in Economics (submittedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
  • OSTI OAI (U.S. Department of Energy Office of Scientific and Technical Information) (submittedVersion)
Funders
  • National Institute of Food and Agriculture (2020-68012-31881, 2011-10006-30357)
  • United States Department of Energy (DE-EE0006297)
  • U.S. Endowment for Forestry & Communities, Inc., Endowment Green Building Partnership—Phase 1 (18-JV-11111137-021)
Topics
  • Physical Sciences › Engineering › Biomedical Engineering › Thermochemical Biomass Conversion Processes
  • Physical Sciences › Engineering › Mechanics of Materials › Forest Biomass Utilization and Management
  • Life Sciences › Agricultural and Biological Sciences › Forestry › Agricultural and Food Sciences
Keywords
forest residues, biochar production, pelletization, global warming potential, minimum selling price, techno-economic feasibility, wildfire mitigation, Pacific Northwest

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-23.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-23.

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Statistics and arithmetic are recomputed, not judged.

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