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The potential to increase biofuel output from a fast pyrolysis-based biorefinery through hydrogen enhancement is assessed for thermal fast pyrolysis (TFP) and catalytic pyrolysis (CAT) processes featuring bio-oil upgrade into gasoline, diesel and heavy hydrocarbon fractions. Results show that utilizing pyrolysis process off-gases to produce synthetic natural gas with an external hydrogen source could provide up to 48.2% (TFP) and 61.2% (CAT) reductions in biomass resource utilization. These savings are enabled by significantly improved carbon efficiency of the hydrogen enhanced designs, with efficiencies increasing from 40.5% to 66.3% for TFP and from 28.9% to 58.6% for CAT. Although the CAT process has a lower biofuel yield than the TFP process, it has a higher potential for hydrogen enhancement and achieves a higher biofuel output than TFP when fully enhanced with external hydrogen. The trade-off to the improved biofuel yield (higher carbon efficiency) is the substantial need for electricity to produce hydrogen via electrolysis, as for every megajoule (MJ) of biomass feedstock, 0.65–0.66 MJ of electricity is needed for the electrolyser.

The performance of an amine-based post-combustion CO2 capture and storage (CCS) process in an existing Kraft pulp mill and an existing pulp and board mill was assessed. The pulp and paper industry is an energy-intensive industry, with significant amounts of CO2 emitted onsite. The majority of this CO2 originates from the combustion of biomass, which renders it carbon neutral if the biomass used by the industry is grown and harvested in a sustainable manner. If the CO2 emissions from the pulp and paper industry were to be captured and permanently stored, then this could make the industry a potential carbon sink. In this evaluation, different configurations of capturing CO2 from the flue gases of the recovery boiler, the multi-fuel boiler and the lime kiln were assessed. For a stand-alone Kraft pulp mill, the excess steam available is sufficient to cover the demand from the CO2 capture plant. For an integrated pulp and board mill, there is less excess steam available for the CO2 capture plant and an auxiliary boiler may be required. The retrofit of a post-combustion CO2 capture plant into an existing pulp mill increases the steam demand by 1-8 GJ/air dried tonne (adt) pulp, depending on the volume of the flue gas treated. This translates to a reduction in the amount of electricity exported to the grid by 0.1-1.0 MWh/adt pulp for a stand-alone Kraft pulp mill, and by 0.1-0.5 MWh/adt pulp for an integrated pulp and board mill. The total potential for negative CO2 emissions amounts to just under 2.0 Mt CO2/a both for the market pulp mill and for the integrated pulp and board mill.

The economic feasibility of retrofitting an amine based post-combustion CO2 capture process to an existing Kraft pulp mill and an existing integrated pulp and board mill has been assessed. This study builds on the technical assessment of the energy performance of the mills when retrofitting a post-combustion CO2 capture process by Onarheim et al. (2017). Between 75 to 100% of the CO2 emissions from the pulp and paper industry originate from the combustion of biomass. If the raw material is sourced sustainably, these emissions are categorized as carbon neutral. Applying sustainably managed biomass in the pulp and paper processes and capturing the resulting CO2 for permanent storage enables the industry to go carbon negative. In this study, the economic impact of retrofitting CO2 capture from the flue gases of the recovery boiler, the multi-fuel boiler and the lime kiln were assessed. The levelized cost of pulp and the cost of CO2 avoided were evaluated based on six different scenarios varying the CO2 tax, incentives for renewable electricity production, with and without recognizing biogenic CO2 emissions as neutral (exempting CO2 emissions from tax or not), and rewarding captured and permanently stored CO2 with negative emissions credit. Results show that the pulp and paper industry has a potential for realizing feasible implementation of large-scale industrial Bio-CCS. For cases where 60-90% of total site CO2 emissions are captured, the cost of avoided CO2 amounts to 52-66/t for the Kraft pulp mill and 71-89/t for the integrated pulp and board mill. The cost of avoided CO2, and thus the realization of Bio-CCS in the pulp and paper industry, is strongly dependent on prevailing policy frameworks such as the EU ETS. In order to reach a levelized cost of pulp similar to the reference mill without CO2 capture, a negative CO2 emission credit of 60-70/t CO2 for the Kraft pulp mill and 70-80/t CO2 for the integrated pulp and board mill will be required. As long as biogenic CO2 emissions that are captured and permanently stored are not recognized as negative and rewarded accordingly there is no economic incentive for the owners of pulp and paper mills to implement CCS. The only way to get the pulp and paper industry to implement and deploy Bio-CCS will need the support of the decision-makers in promoting the right policy framework and regulations to encourage the investment such as strong incentives for negative emissions which are bankable during the long term operation of the mills.

In this study, an alternative operational concept for the blast furnace has been evaluated for an integrated iron and steel mill. The integrated iron and steel mill evaluated was based on the blast furnace and basic oxygen furnace (BF + BOF) hot metal production route equipped with a gas boiler power plant for power production. The alternative assessed was increased pulverized coal injection (PCI) as reducing agent to the blast furnace. Accompanied with a higher rate of oxygen feed to the blast furnace, this reduces the coke consumption in the blast furnace and increases the blast furnace top gas calorific value. The increased calorific value enables combustion of the blast furnace top gas in a high efficiency gas turbine for power production. Combining this modified blast furnace concept with pre-combustion carbon capture will enable a reduction in the total CO2 emissions from the steel mill. Three concepts were evaluated: a modified blast furnace concept without carbon capture, a modified blast furnace concept with MEA-based pre-combustion CO2 capture and a modified blast furnace concept with Selexol-based pre-combustion CO2 capture. All cases were compared to an integrated iron and steel reference case based on the BF + BOF route. Results show that replacing part of the blast furnace coke with increased PCI injection and replacing the gas boiler with a high efficiency gas turbine significantly reduces total CO2 emissions (up to 1.8 Mt/a) from the steel mill. The modified concept imposes significant changes in electricity production on site and becomes an important factor for steel producers operating in the national grids. The different concepts can be implemented stage wise, minimizing the investment and technology risks.

The integration of a fluidized bed fast pyrolysis process producing bio-oil to an existing fluidized bed boiler combined heat and power (CHP) plant is presented. The purpose of this work is to assess the cost and performance of the integrated fast pyrolysis bio-oil production compared to a stand-alone fast pyrolysis bio-oil production plant. The reason for integrating bio-oil production into a fluidized bed boiler is to increase overall energy efficiency and profitability and to decrease the production costs of the bio-oil. In the integrated fast pyrolysis concept hot sand from the fluidized bed boiler is used for heating the fast pyrolysis reactor. Simultaneously, fast pyrolysis process byproducts such as char and noncondensable gases are cofired in the CHP boiler together with the primary forest residue boiler fuel. The assessment shows that the integration decreases the primary fuel requirement of the boiler. The integration causes changes in the net power and heat output of the CHP plant, but the integration can still be more profitable than a stand-alone fast pyrolysis process. The differences in pyrolysis feedstock characteristics are important when comparing integration to stand-alone bio-oil production. In this work pine sawdust and forest residue feedstock were evaluated, of which only the forest residue proved to be economically advantageous for integration to a CHP boiler.

A steady-state Aspen Plus simulation model has been developed that provides estimated mass and energy balances for an industrial fluidizing-bed fast pyrolysis process to produce bio-oil. The tool can be used to assess plant performance under varying process conditions using different feedstocks. A 30 MW lower heating value (LHV) bio-oil plant was modeled utilizing two different feedstock types (pine and forest residues). The fast pyrolysis product yields are functions of feedstock ash content and were calculated on the basis of data generated by a 0.5 t/d fast pyrolysis test unit. The UNIQUAC activity coefficient method was used for the calculation of the liquid phase, and the ideal-gas fugacity coefficient method was used for the vapor-phase calculations. Modeling of the condensation of fast pyrolysis vapors was also verified against experimental data gained from the 0.5 t/d test unit. Production costs were estimated for the two concepts. The results show that the pine-based fast pyrolysis process has be...

The purpose of the research was to validate if the fast pyrolysis bio-oil (FPBO) from used wood would meet both the specifications set by the standard EN 16900–2017 for use of FPBO in industrial boilers and REACH requirements. Commercial used wood Class C was used for fast pyrolysis. The dominant material groups in the feedstock were (virgin) wood (58%) and chemically treated wood (41%). The contents of heavy metals and plastics were low. The pyrolysis experiments were carried out in a bench scale bubbling fluidized bed reactor (1 kg/h). Organic liquid yields were lower (42 − 47%) than with sawdust (64%) but at the same level with those from stored forest residues (46%). The lower organic liquid yield was partly caused by the ash in the feedstock. The liquid product had a high water mass fraction, which resulted in a spontaneous phase separation. The phases were mixed together, and a part of water was evaporated at 40 °C to obtain a single phase product with a water mass fraction of 21%. The liquid product was a homogenous fluid, which in most cases met the demands of the EN standard and the specifications for REACH. Thermodynamic equilibrium calculation suggests that fluidized bed combustion of the pyrolysis char may increase the risk of corrosion and ash melting problems. The recycled wood case is self-sufficient in terms of heat and energy input to the process and will produce excess electricity and district heating for export.

The purpose of this work was to assess the competitiveness of two biomass to transportation fuel processing routes, which were under development in Finland, the U.S. and elsewhere. Concepts included fast pyrolysis (FP), and hydrothermal liquefaction (HTL), both followed by hydrodeoxygenation, and final product refining. This work was carried out as a collaboration between VTT (Finland), and PNNL (USA). The public funding agents for the work were Tekes in Finland and the Bioenergy Technologies Office of the U.S. Department of Energy. The effort was proposed as an update of the earlier comparative technoeconomic assessment performed by the IEA Bioenergy Direct Biomass Liquefaction Task in the 1980s. New developments in HTL and the upgrading of the HTL biocrude product triggered the interest in reinvestigating this comparison of these biomass liquefaction processes. In addition, developments in FP bio-oil upgrading had provided additional definition of this process option, which could provide an interesting comparison.

The Nordic CCS roadmap is developed in the NORDICCS project, a collaborative research project between leading CCS research institutions in the five Nordic countries. The roadmap will outline jointly developed Nordic strategies for widespread implementation of CCS in the Nordic countries in order to help Nordic industries meet a carbon constrained future with a high price on carbon emissions. It will identify pathways and milestones for large-scale Nordic implementation of CCS resulting in beneficial economies of scale that will increase the likelihood of implementation. Several novel cases will be presented that reveal future Nordic opportunities, including industrial CCS where emitters have large point sources of CO2 localized in clusters, and natural gas sweetening with the potential for use of Enhanced Oil Recovery (EOR) to defray the costs. Recommendations will be made for actions relating to joint political work in the Nordic region for improving the framework conditions for CCS.

Six CCS cluster cases specific to the Nordics countries have been identified based. The technical and economical aspect related to capture and transportation for these cases have been investigated. As this is an ongoing study the results are preliminary and storage is yet to be assessed, only the storage location is known. The end goal of the project is to assess the feasibility of the identified CCS cases based on the final technical and economical evaluation. The industries targeted in this study are oil and gas, cement, iron and steel, pulp and paper and heat and power. The industrial cases that have been investigated in this assessment involve all the Nordic countries and cover a wide variation of CO 2 volume, distance between sources, number of sources and distance to storage. The capture costs, with the current assumptions, generally lie in the region of 40-50 EUR/ton and are mainly dependent on the size of the CO 2 emission source. The transportation costs depend strongly on the CO 2 volumes and the transportation distance, and were estimated to approximately 17-20 EUR/ton. Ship transportation seems to be the least expensive transportation method, however there are exceptions.

The urgency to stabilize the global temperature rise at 2°C as highlighted in the IPCC Fifth Assessment Report calls for solutions that can remove CO2 from the atmosphere. Achieving negative CO2 emissions by removing CO2 from the atmosphere is possible by applying carbon capture in processes using biomass (Bio-CCS). Biomass has the capability of withdrawing and storing atmospheric CO2. As a result, CO2 released during biomass combustion can be captured and stored permanently underground, thus depriving the atmosphere of CO2. The objective of this paper is to assess the background for most rational deployment opportunities of Bio-CCS from climate and economic point of view; to evaluate what is the best way to use constrained biomass resources by assessing the effects that raw materials types, different processes and end products have on carbon stocks and on the overall GHG mitigation from the global perspective. A concrete example on how more thorough deployment of Bio-CCS could penetrate in near-term markets is given as a Finnish Bio-CCS roadmap with scenarios highlighting the bottlenecks and constrains. The roadmap assessment is based on power plant, industrial plant and emission database calculations with future projections for existing installations. The technical implementation of Bio-CCS in different industrial sectors goes hand in hand with the development of conventional CCS technology deployment. In general, similar solutions are suitable for capturing CO2 from biomass applications as for fossil fuels. The main differences relate to the size and the location of emission sources (biomass-based installations are often decentralized and of smaller scale compared to fossil-based installations) or to the different kind of impurities in the combustion process, ash and flue gas. However, no principal technical restrictions to the capture of biogenic CO2 exist in energy generation applications or industrial processes. As a consequence, certain Bio-CCS applications are low-hanging fruits for near future deployment of carbon capture assuming that negative emissions are accounted for. In this paper the potential technologies for Bio-CCS and the feasibility of some solutions are compared both from a sustainability and cost point of view. There are four major biomass conversion routes where Bio-CCS is applicable; biochemical conversion (fermentation and hydrolysis), thermo-chemical conversion (e.g. gasification), power production (gasification and combustion) and industrial processes. In addition to ethanol fermentation the thermo-chemical biomass conversion processes are considered the first-phase targets for applying capture of CO2, both from a logistic and cost point of view. The main Bio-CCS technologies assessed in this study are Fischer-Tropsch diesel production, bio-SNG production, lignocellulosic ethanol production, torrefaction and biomass based power production such as co-firing biomass in a coal-based condensing power plant and biomass-based CHP (combined heat and power) production. The most applicable industry sector for introduction of Bio-CCS is obviously pulp and paper industry but some potential exists also in cement industry, iron and steel industry and oil and gas refineries. The emission reduction potential in different technologies is very much bound to the scale of installations which again is generally limited by the scale of technologies and availability of biomass raw material. The biggest reduction potential for the studied cases per industrial site can take place in iron and steel industry (~3 Mt/a), pulp and paper industry (~1.3 Mt/a) and in combined heat power (CHP) production (~2.5 Mt/a) as opposed to straw ethanol production of smaller scale (~0.1 Mt/a). However, the CO2 avoidance potential per unit of biomass raw material utilized is highest in co-firing (20tCO2/toe), iron and steel industry (10tCO2/toe) and in CHP production (8tCO2/toe) whereas straw ethanol has lowest potential also in this category (1.5tCO2/toe). The cost estimations show a theoretical economic advantage of Bio-CCS over fossil CCS on carbon prices when the carbon sink effect is accounted for. The total costs for Bio-CCS vary from 35€/ton to 300€/ton CO2 stored depending on the technology. As the potential of Bio-CCS is bound to the availability and usage of biomass raw materials, the sustainability of the raw materials is of essence. The current biomass flows and potentials set the initial limits for the wider deployment of Bio-CCS. Efficient utilization of constrained resources is an essential question, when the target is to optimize the impact on the system level, from the society point of view. The ultimate objective is to suggest whether deployment of CCS has the desired impact on the atmospheric CO2 concentration. As biomass can be used in many ways, the primary purpose of utilization and products containing biogenic carbon also adds up to this. When biomass is utilized for products other than energy, the impact to environment and economy differs. The opportunities with these solutions, realistic potential and the main threats related to Bio- CCS are discussed in the light of sustainability and economic potential.