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In India, cow dung is widely utilized to create formulations that serve as effective plant growth enhancers with antimicrobial properties. The cow dung-derived handmade paper manufacturing process produces two waste-liquor streams, a Raw Liquor (RL) produced through the dewatering of the cow-dung slurry and a Black Liquor (BL) produced during the soda pulping of dewatered cow dung. The present study explored the potential of these waste streams to be used as plant biofertilizers for germination and cultivation of Vigna radiata seeds (mung bean, IPM-02-03 variety). An in vitro assay for seed germination efficiency and a pot study for plant growth promotion (PGP) activity were used to assess this potential. The in vitro assay demonstrated that nutrient-rich RL, with its 100% seed germination efficiency (better than the 85.7% of tap water) was an effective biofertilizer for seed germination. In contrast, BL yielded poor seed germination efficiency. The pot study showed that water irrigation led to good seed germination, survival, plant rooting and shooting, but it was probably deprived of nutrients for inducing good grain yields. When water was replaced with RL, it was able to replicate the results, but with good grain yields. In contrast, BL produced poorer germination, seed survival and PGP results. The poor biofertilization efficiency of BL was most probably due to the nutrient losses and toxic chemicals produced in the harsh pulping process. The results showed that RL, though considered a waste stream, is sufficiently nutrient-rich to act as an effective biofertilizer for germinating mung bean seeds and promoting plant growth and grain yields.

Direct carbon fuel cell (DCFC) with higher power efficiency and lesser emissions is being viewed as a potential clean energy source. The application of renewable biochar as fuel for DCFC is found to be feasible to replace coal or carbon black for power generation. Black liquor from the paper production might be a suitable fuel source for DCFC due to its high lignin or carbon content. In this study, the feasibility of using compound extracted from black liquor as fuel source for DCFC was investigated in the aspect of physico-chemical and electrochemical properties. Suitable pyrolysis temperature in producing biochar from black liquor compound was first investigated. Results have shown that fixed carbon and ash content increased slightly with increasing pyrolysis temperature. The ash content is made up of majority of silica as depicted in FESEM-EDX results. Oxygen containing functional group was decomposed under high pyrolysis temperature of 700°C and 800°C. Besides, biochar obtained at 500°C of pyrolysis temperature has given the highest power density of 1.22 mW cm-2 whereas 1.44 mW cm-2 was obtained from coal which was used as the control. Future work on ash removal from the black liquor prior to pyrolysis might improve the potential of black liquor derived compound as a fuel source for DCFC.

Ambitious fossil-free targets imposed on the aviation industry worldwide demand a large volumetric supply of sustainable aviation fuel (SAF) to meet. Sweden's commitment to a 30% volume SAF blending target by 2030 attracts interest in local production. However, the sustainability of local production is largely unknown. Addressing this gap, we aim to explore potential SAF technology pathways and assess their environmental performances in Sweden. To do so, we utilize a socio-technical system (STS) approach for pathways selection and prospective life cycle assessment (LCA) for environmental impact assessment. As a result, we identify two lignocellulosic-based and two electrofuel-based pathways and evaluate their global warming potential, mineral depletion potential, ionizing radiation, land use, freshwater ecotoxicity and human toxicity impact in comparison to jet fuel. Our findings show that the well-to-wake global warming potential (100 years) of 30% SAF is on average 20% lower than that of jet fuel, with non-carbon dioxide species emitted in flight being the major contributors, prompting the need for urgent research efforts to mitigate their potential impacts. Under the assumption that no burdens are allocated to waste material used as feedstock, lignocellulosic-based 100% SAF has a well-to-pump climate impact (100 years) ranging from 0.6 to 1.5 g CO2−eq/MJ compared to jet fuel's 10.5 g CO2−eq/MJ. In contrast, the well-to-pump climate impact (100 years) of electrofuel-based 100% SAF (ranging from 7.8 to 8.2 g CO2−eq/MJ) is only marginally lower than that of jet fuel, mainly attributed to emissions from steel and concrete produced for wind turbine manufacturing. In general, the use of electricity generated by wind power could shift the potential environmental burden associated with jet fuel from global warming to mineral depletion, land use, freshwater ecotoxicity and human toxicity. The STS approach underscores the need to prioritize changes in systems underpinning, QC 20230613

Direct carbon fuel cell (DCFC) with higher power efficiency and lesser emissions is being viewed as a potential clean energy source. The application of renewable biochar as fuel for DCFC is found to be feasible to replace coal or carbon black for power generation. Black liquor from the paper production might be a suitable fuel source for DCFC due to its high lignin or carbon content. In this study, the feasibility of using compound extracted from black liquor as fuel source for DCFC was investigated in the aspect of physico-chemical and electrochemical properties. Suitable pyrolysis temperature in producing biochar from black liquor compound was first investigated. Results have shown that fixed carbon and ash content increased slightly with increasing pyrolysis temperature. The ash content is made up of majority of silica as depicted in FESEM-EDX results. Oxygen containing functional group was decomposed under high pyrolysis temperature of 700°C and 800°C. Besides, biochar obtained at 500°C of pyrolysis temperature has given the highest power density of 1.22 mW cm-2 whereas 1.44 mW cm-2 was obtained from coal which was used as the control. Future work on ash removal from the black liquor prior to pyrolysis might improve the potential of black liquor derived compound as a fuel source for DCFC.

The aim of this work was to obtain two biopolyols from the liquid residue resulting from the precipitation of lignin contained in two different black liquors, Eucalyptus globulus organosolv black liquor (EOBL) and Pinus radiata organosolv black liquor (POBL), thus adding value to this residue. Eucalyptus organosolv polyol (EOP) and Pine organosolv polyol (POP) were characterized to know their viscosity, hydroxyl number (IOH), and functionality according to the corresponding standard American Society for Testing Materials (ASTM). The molecular weight of the biopolyols was measured through gel permeation chromatography (GPC); the chemical structure and composition were characterized by Fourier transform infrared (FTIR) and gas chromatography–mass spectrometry (GC-MS), respectively; and the thermal degradation (TGA) of the two biopolyols was determined. The biopolyols showed suitable properties to be employed in the production of polyurethanes (PU).

The largest use of fossil petroleum is the production of fuels. Hence, finding sustainable alter-natives is an important step to reduce the emissions of greenhouse gases. One such alternative is to produce fuel from biomass, such as waste products from agriculture and the forest indus-try. In Sweden, the forest industry is an important part of the economy. The pulp mills pro-duce an excessive amount of a by-product called black liquor, which has a high content of the biopolymer lignin. The company SunCarbon is developing a process to separate the lignin from the black liquor, purify it and recycle the remaining chemicals to the pulp mill. The purified lignin is to be mixed with a carrier oil to a lignin-rich oil that can be used in refineries to pro-duce fuel such as gasoline and diesel. One of the steps in the process is the heat treatment, which has the purpose to degrade espe-cially hemicellulose, but also lignin, into smaller molecule fractions. A problem with the heat treatment is the corrosion of steel in the reactor vessel, causing the release of metals that pol-lute the product oil and that are difficult to remove. To solve this problem, the idea to use mi-crowave heating has been introduced. Traditional heating methods require high temperature of the reactor vessel to heat up the medium by conduction and convection. Microwaves heat the material directly and thus the prior heating of the reactor vessel is not required. This means that the temperature of the reactor vessel should be lower and enable for the use of Teflon vessels that do not leach metals to the liquor. The direct heating of the material should also enable faster heating rate. In this Master Thesis, microwave heat treatment was investigated and compared to traditional heat treatment in a steel autoclave. Evaluation was made by ana-lysing the degradation of hemicellulose and lignin with chromatographical methods and lignin yield in the subsequent separation by acidulation in the SunCarbon proces, Popular Science Summary: Production of biofuel – processing of paper mill by-products to fuel components A new process is being developed to produce fuel from the paper mill by-product black liquor. In this Thesis, a new heat treatment method was investigated to degrade large molecules in the black liquor to smaller ones, using microwaves. The production of fuel is the largest use of fossil petroleum. Therefore, finding sustainable alternatives is an important step to reduce the emissions of greenhouse gases that are causing climate change. One such alternative is to use biomass, for example waste products from the agriculture and the forest industry. In Sweden, the forest industry is an important part of the national economy. The pulp and paper mills produce excessive amounts of a by-product called black liquor, which today is used to produce steam for energy production in the mills. However, the black liquor has a high content of the macromolecule lignin, which has the potential to be used for more refined and valuable products. Lignin is one of the main components of wood, providing the wood with its firm structure. The lignin molecules consist of various rings of carbon atoms linked together in complex irregular networks. Breaking down these networks into smaller fragments, the resulting components are similar to molecules found in petrol. An idea is to use black liquor to produce biofuel similar to gasoline or diesel. SunCarbon is developing a process that can be integrated with pulp mills with the intention to extract the lignin from the black liquor and recycle the other chemicals to the mill. The lignin is separated from the black liquor by a series of processes starting with membrane filtration, after which follows a heat treatment that breaks down lignin and other large molecules into smaller components. It is especially important to degrade hemicellulose, which is another molecule found in wood. Otherwise, the hemicellulose may cause problems downstream i

The largest use of fossil petroleum is the production of fuels. Hence, finding sustainable alter-natives is an important step to reduce the emissions of greenhouse gases. One such alternative is to produce fuel from biomass, such as waste products from agriculture and the forest indus-try. In Sweden, the forest industry is an important part of the economy. The pulp mills pro-duce an excessive amount of a by-product called black liquor, which has a high content of the biopolymer lignin. The company SunCarbon is developing a process to separate the lignin from the black liquor, purify it and recycle the remaining chemicals to the pulp mill. The purified lignin is to be mixed with a carrier oil to a lignin-rich oil that can be used in refineries to pro-duce fuel such as gasoline and diesel. One of the steps in the process is the heat treatment, which has the purpose to degrade espe-cially hemicellulose, but also lignin, into smaller molecule fractions. A problem with the heat treatment is the corrosion of steel in the reactor vessel, causing the release of metals that pol-lute the product oil and that are difficult to remove. To solve this problem, the idea to use mi-crowave heating has been introduced. Traditional heating methods require high temperature of the reactor vessel to heat up the medium by conduction and convection. Microwaves heat the material directly and thus the prior heating of the reactor vessel is not required. This means that the temperature of the reactor vessel should be lower and enable for the use of Teflon vessels that do not leach metals to the liquor. The direct heating of the material should also enable faster heating rate. In this Master Thesis, microwave heat treatment was investigated and compared to traditional heat treatment in a steel autoclave. Evaluation was made by ana-lysing the degradation of hemicellulose and lignin with chromatographical methods and lignin yield in the subsequent separation by acidulation in the SunCarbon proces, Popular Science Summary: Production of biofuel – processing of paper mill by-products to fuel components A new process is being developed to produce fuel from the paper mill by-product black liquor. In this Thesis, a new heat treatment method was investigated to degrade large molecules in the black liquor to smaller ones, using microwaves. The production of fuel is the largest use of fossil petroleum. Therefore, finding sustainable alternatives is an important step to reduce the emissions of greenhouse gases that are causing climate change. One such alternative is to use biomass, for example waste products from the agriculture and the forest industry. In Sweden, the forest industry is an important part of the national economy. The pulp and paper mills produce excessive amounts of a by-product called black liquor, which today is used to produce steam for energy production in the mills. However, the black liquor has a high content of the macromolecule lignin, which has the potential to be used for more refined and valuable products. Lignin is one of the main components of wood, providing the wood with its firm structure. The lignin molecules consist of various rings of carbon atoms linked together in complex irregular networks. Breaking down these networks into smaller fragments, the resulting components are similar to molecules found in petrol. An idea is to use black liquor to produce biofuel similar to gasoline or diesel. SunCarbon is developing a process that can be integrated with pulp mills with the intention to extract the lignin from the black liquor and recycle the other chemicals to the mill. The lignin is separated from the black liquor by a series of processes starting with membrane filtration, after which follows a heat treatment that breaks down lignin and other large molecules into smaller components. It is especially important to degrade hemicellulose, which is another molecule found in wood. Otherwise, the hemicellulose may cause problems downstream i

The largest use of fossil petroleum is the production of fuels. Hence, finding sustainable alter-natives is an important step to reduce the emissions of greenhouse gases. One such alternative is to produce fuel from biomass, such as waste products from agriculture and the forest indus-try. In Sweden, the forest industry is an important part of the economy. The pulp mills pro-duce an excessive amount of a by-product called black liquor, which has a high content of the biopolymer lignin. The company SunCarbon is developing a process to separate the lignin from the black liquor, purify it and recycle the remaining chemicals to the pulp mill. The purified lignin is to be mixed with a carrier oil to a lignin-rich oil that can be used in refineries to pro-duce fuel such as gasoline and diesel. One of the steps in the process is the heat treatment, which has the purpose to degrade espe-cially hemicellulose, but also lignin, into smaller molecule fractions. A problem with the heat treatment is the corrosion of steel in the reactor vessel, causing the release of metals that pol-lute the product oil and that are difficult to remove. To solve this problem, the idea to use mi-crowave heating has been introduced. Traditional heating methods require high temperature of the reactor vessel to heat up the medium by conduction and convection. Microwaves heat the material directly and thus the prior heating of the reactor vessel is not required. This means that the temperature of the reactor vessel should be lower and enable for the use of Teflon vessels that do not leach metals to the liquor. The direct heating of the material should also enable faster heating rate. In this Master Thesis, microwave heat treatment was investigated and compared to traditional heat treatment in a steel autoclave. Evaluation was made by ana-lysing the degradation of hemicellulose and lignin with chromatographical methods and lignin yield in the subsequent separation by acidulation in the SunCarbon proces, Popular Science Summary: Production of biofuel – processing of paper mill by-products to fuel components A new process is being developed to produce fuel from the paper mill by-product black liquor. In this Thesis, a new heat treatment method was investigated to degrade large molecules in the black liquor to smaller ones, using microwaves. The production of fuel is the largest use of fossil petroleum. Therefore, finding sustainable alternatives is an important step to reduce the emissions of greenhouse gases that are causing climate change. One such alternative is to use biomass, for example waste products from the agriculture and the forest industry. In Sweden, the forest industry is an important part of the national economy. The pulp and paper mills produce excessive amounts of a by-product called black liquor, which today is used to produce steam for energy production in the mills. However, the black liquor has a high content of the macromolecule lignin, which has the potential to be used for more refined and valuable products. Lignin is one of the main components of wood, providing the wood with its firm structure. The lignin molecules consist of various rings of carbon atoms linked together in complex irregular networks. Breaking down these networks into smaller fragments, the resulting components are similar to molecules found in petrol. An idea is to use black liquor to produce biofuel similar to gasoline or diesel. SunCarbon is developing a process that can be integrated with pulp mills with the intention to extract the lignin from the black liquor and recycle the other chemicals to the mill. The lignin is separated from the black liquor by a series of processes starting with membrane filtration, after which follows a heat treatment that breaks down lignin and other large molecules into smaller components. It is especially important to degrade hemicellulose, which is another molecule found in wood. Otherwise, the hemicellulose may cause problems downstream i

Promoting the deployment of forest-based drop-in and high blend biofuels is considered strategically important in Sweden but many aspects of the overall performance of the foremost production technologies are as yet unexamined. This paper evaluates the technology maturity, profitability, investment requirements, GHG performance and Swedish biofuel production potential of six commercially interesting forest-based biofuel production pathways. Significant heterogeneity in technology maturity was observed. Lack of technical demonstration in industrially representative scales renders the liquefaction-hydrotreatment route for drop-in biofuels less mature than its gasification-catalytic upgrading counterpart. It is a paradox that short-term priority being accorded to pathways with the lowest technology maturity. Nth-of-a-kind investments in (a) gasification-based methanol, (b) hydropyrolysis-based petrol/diesel, and (c) lignin depolymerization-based petrol/diesel were profitable for a range of plant sizes. The profitability of pulp mill-integrated small gasification units (<100 MW) goes against the common perception of gasification being economically feasible only in large scales. New low-cost options for debottlenecking production at recovery boiler-limited kraft mills appear worth investigating. GHG emission reductions ranged from 66 to 95%; a penalty was incurred for high consumption of natural gas-based hydrogen. Swedish biofuel production potentials ranged from 4 to 27 TWh/y but a more feasible upper limit is 12–15 TWh/y.

A reference lignin separated from an industrial softwood kraft black liquor via an improved LignoBoost process was compared to four other lignins derived from the same liquor. The four lignins were produced by using a) pH-fractionation within the LignoBoost process, b) ultrafiltration of black liquor prior to the LignoBoost process, and c) solvent leaching of the reference lignin using methanol and d) ethanol.Lignin compositional characteristics and thermal properties were compared, and monofilament extrusion used to assess their potential for successful melt spinning at the 24 filament scale. The lignin prepared by ethanol leaching of the reference lignin was found to be most appropriate for potential pilot scale fibre production. This was owing to a high purity, lower comparative glass transition temperature (Tg), and good spinning performance.Thermal pretreatments of the ethanol leached lignin gave a selection of enhanced lignins which were characterized for comparison, and melt spun on pilot multifilament equipment. The enhanced lignins could be continuously melt spun giving filaments with diameters as low as 10 μm and with minimal defects. Conversion of selected filaments provided carbon fibres with a tensile strength of 1259 ± 159 MPa, tensile modulus of 67 ± 3 GPa and diameter of 7.3 ± 0.5 μm.

Fuel combustion for transport was responsible for 24% of EU-28 greenhouse gas (GHG) emissions in 2016. Member states are expected to ensure that the share of renewable energy in the transport sector is at least 14% by 2030. Some countries, such as Sweden, have more ambitious targets. By 2030, GHG emissions from domestic transport are to be reduced by 70% relative to 2010 levels. A national emission reduction scheme launched in 2018 obliges suppliers of diesel and petrol to reduce their GHG footprints annually by a pre-determined amount, which could further stimulate demand for drop-in biofuels, and potentially even high blend alternatives. However, recent changes to Swedish domestic policy and the EU-wide RED sustainability criteria mean that biodiesel from some common crop-based biomaterials may no longer qualify for certain important tax benefits or count towards the 2030 renewables target. Given Sweden’s extensive forest products industry, woody residue and by-products, such as branches, toppings and black liquor (BL) are viewed as strategically important feedstock for the production of RED-compliant biofuels. Upgrading kraft BL to biofuels can also potentially help pulp mills expand their product base. Two conversion routes are seen as industrially relevant in the short-to-medium term: (a) gasification-catalytic synthesis, (b) liquefaction-hydrotreatment. The production of methanol and dimethyl ether from kraft BL has been demonstrated extensively in a pilot facility, although a complete analysis of technical performance based on experimental measurements has not been performed previously. Since BL is not transportable, the biofuel production potential of a mill is effectively set by its pulp throughput, which limits potential economies-of-scale. BL is rich in catalytically active sodium compounds and blending it with other woody residue-based feedstock, such as pyrolysis oil (PO) before gasification allows the partial decoupling of biofuel production capacity f

A reference lignin separated from an industrial softwood kraft black liquor via an improved LignoBoost process was compared to four other lignins derived from the same liquor. The four lignins were produced by using a) pH-fractionation within the LignoBoost process, b) ultrafiltration of black liquor prior to the LignoBoost process, and c) solvent leaching of the reference lignin using methanol and d) ethanol.Lignin compositional characteristics and thermal properties were compared, and monofilament extrusion used to assess their potential for successful melt spinning at the 24 filament scale. The lignin prepared by ethanol leaching of the reference lignin was found to be most appropriate for potential pilot scale fibre production. This was owing to a high purity, lower comparative glass transition temperature (Tg), and good spinning performance.Thermal pretreatments of the ethanol leached lignin gave a selection of enhanced lignins which were characterized for comparison, and melt spun on pilot multifilament equipment. The enhanced lignins could be continuously melt spun giving filaments with diameters as low as 10 μm and with minimal defects. Conversion of selected filaments provided carbon fibres with a tensile strength of 1259 ± 159 MPa, tensile modulus of 67 ± 3 GPa and diameter of 7.3 ± 0.5 μm.

The world is about to shift from fossil fuel dependency to independency. The national agenda of Sweden has put forth future goals of becoming a zero net greenhouse gas emitter by the year 2045 and before that, having an 80 % fossil fuel independent transportation fleet by 2030. In order to achieve these goals, the form of energy used in the transport sector needs to be changed into a more renewable solution. Biogas could be part of the solution. The aim of this report has been to review earlier research regarding the future biogas potential in Sweden and to examine how realistic and practically feasible these are. Three of the substrates that has shown the highest future potential according to earlier research; energy crops, manure and black liquor has been chosen for investigating their future potential. Interviews was made with biogas researcher in Sweden as well as government employees working with biogas and other biofuels. Scenario building was another method used were the report have created four future scenarios with varying optimistically future economic and technical outcomes using more practical limitations and restrictions. The result was a combined future potential of between 0,42 – 77,54 TWh/annually from all three substrates using the values and information gathered from the interviewers regarding how to calculate the potential. The result shows that depending on how lucrative the future financial support systems and subsidies as well as how efficient the technical breakthroughs will be, biogas can become a large contributor to the transport sectors transition in becoming less fossil fuel dependent.

In paper pulp production, many details can be optimized. For optimal separation of soap from black liquor, it is important to know the amount of soap in the black liquor. A project to produce a method for sampling black liquor and a method for measuring how much soap is present in black liquor by centrifugation was done at Södra Cell Mönsterås. Through centrifugation faster analysis can be done. It took a long time to develop a satisfactory sampling method, but with the help of careful checking of temperature and time, a method was achieved that worked at temperatures between 90 and 100°C, which were the temperatures that were most frequently found, but are higher than the optimum temperature for soap separation. The black liquor turned out to be inhomogeneous, so the project failed to obtain an optimal analysis method within the framework of this project. In the experiment, the centrifuge settings were optimized to 87°C, 2500 rpm and 10 minutes Further attempts could provide more optimal settings for the centrifuge and a substitute for black liquor could make a validation of the centrifuge possible., Pappersmassaproduktion är komplex, och en rad faktorer kan optimeras. En viktig parameter vid såpavskiljning är innehållet såpa i svartlut eftersom en värdefull produkt, tallolja utvinns av såpa. Projektet syftar till att ta fram en metod för provtagning av svartlut och en metod för att mäta halten såpa i svartluten genom centrifugering. Genom centrifugering kan snabbare analyser göras. Arbetet har utförts på Södra Cell Mönsterås. Arbetet att utveckla en tillfredsställande provtagningsmetod var komplicerad, men med hjälp av noggrann koll på temperatur och tid uppnåddes en metod som fungerade vid temperaturer mellan 90 och 100°C, vilket var de temperaturer som oftast fanns, men som är högre än optimal temperatur för såpavskiljning. Svartluten visade sig vara inhomogen, därför lyckades det inte att få fram en optimal analysmetod inom ramen av detta projekt. I försöket optimerades centrifugens inställningar till 87°C, 2500 rpm (varv per minut) och 10 minuter. Vidare försök skulle kunna ge mer optimala inställningar för centrifugen genom den utvecklade prov, och ett substitut för svartlut skulle kunne göra en validering av centrifugen möjlig.

Promoting the deployment of forest-based drop-in and high blend biofuels is considered strategically important in Sweden but many aspects of the overall performance of the foremost production technologies are as yet unexamined. This paper evaluates the technology maturity, profitability, investment requirements, GHG performance and Swedish biofuel production potential of six commercially interesting forest-based biofuel production pathways. Significant heterogeneity in technology maturity was observed. Lack of technical demonstration in industrially representative scales renders the liquefaction-hydrotreatment route for drop-in biofuels less mature than its gasification-catalytic upgrading counterpart. It is a paradox that short-term priority being accorded to pathways with the lowest technology maturity. Nth-of-a-kind investments in (a) gasification-based methanol, (b) hydropyrolysis-based petrol/diesel, and (c) lignin depolymerization-based petrol/diesel were profitable for a range of plant sizes. The profitability of pulp mill-integrated small gasification units (<100 MW) goes against the common perception of gasification being economically feasible only in large scales. New low-cost options for debottlenecking production at recovery boiler-limited kraft mills appear worth investigating. GHG emission reductions ranged from 66 to 95%; a penalty was incurred for high consumption of natural gas-based hydrogen. Swedish biofuel production potentials ranged from 4 to 27 TWh/y but a more feasible upper limit is 12–15 TWh/y.

Promoting the deployment of forest-based drop-in and high blend biofuels is considered strategically important in Sweden but many aspects of the overall performance of the foremost production technologies are as yet unexamined. This paper evaluates the technology maturity, profitability, investment requirements, GHG performance and Swedish biofuel production potential of six commercially interesting forest-based biofuel production pathways. Significant heterogeneity in technology maturity was observed. Lack of technical demonstration in industrially representative scales renders the liquefaction-hydrotreatment route for drop-in biofuels less mature than its gasification-catalytic upgrading counterpart. It is a paradox that short-term priority being accorded to pathways with the lowest technology maturity. Nth-of-a-kind investments in (a) gasification-based methanol, (b) hydropyrolysis-based petrol/diesel, and (c) lignin depolymerization-based petrol/diesel were profitable for a range of plant sizes. The profitability of pulp mill-integrated small gasification units (<100 MW) goes against the common perception of gasification being economically feasible only in large scales. New low-cost options for debottlenecking production at recovery boiler-limited kraft mills appear worth investigating. GHG emission reductions ranged from 66 to 95%; a penalty was incurred for high consumption of natural gas-based hydrogen. Swedish biofuel production potentials ranged from 4 to 27 TWh/y but a more feasible upper limit is 12–15 TWh/y.

The world is about to shift from fossil fuel dependency to independency. The national agenda of Sweden has put forth future goals of becoming a zero net greenhouse gas emitter by the year 2045 and before that, having an 80 % fossil fuel independent transportation fleet by 2030. In order to achieve these goals, the form of energy used in the transport sector needs to be changed into a more renewable solution. Biogas could be part of the solution. The aim of this report has been to review earlier research regarding the future biogas potential in Sweden and to examine how realistic and practically feasible these are. Three of the substrates that has shown the highest future potential according to earlier research; energy crops, manure and black liquor has been chosen for investigating their future potential. Interviews was made with biogas researcher in Sweden as well as government employees working with biogas and other biofuels. Scenario building was another method used were the report have created four future scenarios with varying optimistically future economic and technical outcomes using more practical limitations and restrictions. The result was a combined future potential of between 0,42 – 77,54 TWh/annually from all three substrates using the values and information gathered from the interviewers regarding how to calculate the potential. The result shows that depending on how lucrative the future financial support systems and subsidies as well as how efficient the technical breakthroughs will be, biogas can become a large contributor to the transport sectors transition in becoming less fossil fuel dependent.

In paper pulp production, many details can be optimized. For optimal separation of soap from black liquor, it is important to know the amount of soap in the black liquor. A project to produce a method for sampling black liquor and a method for measuring how much soap is present in black liquor by centrifugation was done at Södra Cell Mönsterås. Through centrifugation faster analysis can be done. It took a long time to develop a satisfactory sampling method, but with the help of careful checking of temperature and time, a method was achieved that worked at temperatures between 90 and 100°C, which were the temperatures that were most frequently found, but are higher than the optimum temperature for soap separation. The black liquor turned out to be inhomogeneous, so the project failed to obtain an optimal analysis method within the framework of this project. In the experiment, the centrifuge settings were optimized to 87°C, 2500 rpm and 10 minutes Further attempts could provide more optimal settings for the centrifuge and a substitute for black liquor could make a validation of the centrifuge possible., Pappersmassaproduktion är komplex, och en rad faktorer kan optimeras. En viktig parameter vid såpavskiljning är innehållet såpa i svartlut eftersom en värdefull produkt, tallolja utvinns av såpa. Projektet syftar till att ta fram en metod för provtagning av svartlut och en metod för att mäta halten såpa i svartluten genom centrifugering. Genom centrifugering kan snabbare analyser göras. Arbetet har utförts på Södra Cell Mönsterås. Arbetet att utveckla en tillfredsställande provtagningsmetod var komplicerad, men med hjälp av noggrann koll på temperatur och tid uppnåddes en metod som fungerade vid temperaturer mellan 90 och 100°C, vilket var de temperaturer som oftast fanns, men som är högre än optimal temperatur för såpavskiljning. Svartluten visade sig vara inhomogen, därför lyckades det inte att få fram en optimal analysmetod inom ramen av detta projekt. I försöket optimerades centrifugens inställningar till 87°C, 2500 rpm (varv per minut) och 10 minuter. Vidare försök skulle kunna ge mer optimala inställningar för centrifugen genom den utvecklade prov, och ett substitut för svartlut skulle kunne göra en validering av centrifugen möjlig.

Fuel combustion for transport was responsible for 24% of EU-28 greenhouse gas (GHG) emissions in 2016. Member states are expected to ensure that the share of renewable energy in the transport sector is at least 14% by 2030. Some countries, such as Sweden, have more ambitious targets. By 2030, GHG emissions from domestic transport are to be reduced by 70% relative to 2010 levels. A national emission reduction scheme launched in 2018 obliges suppliers of diesel and petrol to reduce their GHG footprints annually by a pre-determined amount, which could further stimulate demand for drop-in biofuels, and potentially even high blend alternatives. However, recent changes to Swedish domestic policy and the EU-wide RED sustainability criteria mean that biodiesel from some common crop-based biomaterials may no longer qualify for certain important tax benefits or count towards the 2030 renewables target. Given Sweden’s extensive forest products industry, woody residue and by-products, such as branches, toppings and black liquor (BL) are viewed as strategically important feedstock for the production of RED-compliant biofuels. Upgrading kraft BL to biofuels can also potentially help pulp mills expand their product base. Two conversion routes are seen as industrially relevant in the short-to-medium term: (a) gasification-catalytic synthesis, (b) liquefaction-hydrotreatment. The production of methanol and dimethyl ether from kraft BL has been demonstrated extensively in a pilot facility, although a complete analysis of technical performance based on experimental measurements has not been performed previously. Since BL is not transportable, the biofuel production potential of a mill is effectively set by its pulp throughput, which limits potential economies-of-scale. BL is rich in catalytically active sodium compounds and blending it with other woody residue-based feedstock, such as pyrolysis oil (PO) before gasification allows the partial decoupling of biofuel production capacity f

The influence of sodium ion concentration [Na+] on the dissolution of carbohydrates in black liquor (BL) during flow-through kraft cooking of Scots pine wood meal (Pinus sylvestris) was studied. Fractions of BL were collected at different times and the carbohydrate content of the various fractions was analysed. Lignin was precipitated from the BL by lowering the pH, and the carbohydrate content of the precipitated lignins (L-prec) was also examined. The molecular weight distribution (MWD) of the L-prec samples was analysed. Xylose (Xyl) was found to be the most predominant sugar in BL aside from arabinose (Ara) and galactose (Gal), while the amounts of these sugars decreased with increasing levels of [Na+] in the cooking liquor. The minor amounts of mannose (Man) found in BL was not influenced by the [Na+]. The effects of NaCl and Na2CO3 on the carbohydrate dissolution were similar, but slightly lower concentrations of Ara and Xyl were found in the case of NaCl application. All of the L-prec samples contained some carbohydrate residues, the contents of which increased with increasing cooking time and decreased with higher [Na+]. It can be concluded that arabinoglucuronoxylan (AGX) along with arabinogalactans (AG) and arabinan, are covalently linked to lignin. The glucose (Glc) residue detected in L-prec may originate from 1,3-beta-glucan linked to lignin., QC 20180726

After the kraft or soda pulping of lignocellulosic materials to produce pulp suitable for papermaking, the spent pulping liquor typically has been recovered by multi-effect evaporation, followed by incineration in a recovery boiler. This review article considers one unit operation, eutectic freeze crystallization (EFC), that may have potential to save some of the energy that is presently consumed in the evaporation step during recovery of inorganic chemicals from spent pulping liquor. Based on a review of the literature it appears that EFC can be employed to obtain relatively pure sodium sulfate and sodium carbonate, along with relatively pure water (in the form of ice) from the spent liquor, under the assumption that lignin previously has been removed by acidification and precipitation. Issues of inorganic scale formation, during the operation of an EFC process applied to lignin-free black liquor, will require research attention. The chemical reactions to regenerate the active pulping chemicals sodium hydroxide and sodium sulfide from sodium carbonate, sodium sulfate, and other compounds isolated by EFC can be carried out either in a separate operation or by returning the materials to the feed of an existing recovery boiler., QC 20190116

Biorefineries for the production of fuels, chemicals, or materials can be an important contributor to reducing dependence on fossil fuels. The economic performance of the biorefinery supply chain can be increased by, for example, industrial integration to utilise excess heat and products, increasing size to improve economy of scale, and using intermediate upgrading to reduce feedstock transport cost. To enable a large-scale introduction of biorefineries it is important to identify cost efficient supply chain configurations. This work investigates a lignocellulosic biorefinery concept integrated with forest industry, focusing on how different economic conditions affect the preferred supply chain configurations. The technology investigated is black liquor gasification, with and without the addition of pyrolysis liquids to increase production capacity. Primarily, it analyses trade-offs between high biomass conversion efficiency and economy of scale effects, as well as the selection of centralised vs. decentralised supply chain configurations. The results show the economic advantage for biomass efficient configurations, when the biorefinery investment is benefited from an alternative investment credit due to the replacement of current capital-intensive equipment at the host industry. However, the investment credit received heavily influenced the cost of the biorefinery and clearly illustrates the benefit for industrial integration to reduce the cost of biorefineries. There is a benefit for a decentralised supply chain configuration under very high biomass competition. However, for lower biomass competition, site-specific conditions will impact the favourability of either centralised or decentralised supply chain configurations., Validerad;2018;Nivå 2;2018-09-19 (svasva);Full text license: CC BY

Biorefineries for the production of fuels, chemicals, or materials can be an important contributor to reducing dependence on fossil fuels. The economic performance of the biorefinery supply chain can be increased by, for example, industrial integration to utilise excess heat and products, increasing size to improve economy of scale, and using intermediate upgrading to reduce feedstock transport cost. To enable a large-scale introduction of biorefineries it is important to identify cost efficient supply chain configurations. This work investigates a lignocellulosic biorefinery concept integrated with forest industry, focusing on how different economic conditions affect the preferred supply chain configurations. The technology investigated is black liquor gasification, with and without the addition of pyrolysis liquids to increase production capacity. Primarily, it analyses trade-offs between high biomass conversion efficiency and economy of scale effects, as well as the selection of centralised vs. decentralised supply chain configurations. The results show the economic advantage for biomass efficient configurations, when the biorefinery investment is benefited from an alternative investment credit due to the replacement of current capital-intensive equipment at the host industry. However, the investment credit received heavily influenced the cost of the biorefinery and clearly illustrates the benefit for industrial integration to reduce the cost of biorefineries. There is a benefit for a decentralised supply chain configuration under very high biomass competition. However, for lower biomass competition, site-specific conditions will impact the favourability of either centralised or decentralised supply chain configurations., Validerad;2018;Nivå 2;2018-09-19 (svasva)

It is vital to perform system analysis on integrated biomass gasification in chemical recovery systems in pulp and paper and heat and power plants for polygeneration applications. The proposed integration complements existing pulp and paper and heat and power production systems with production of chemicals such as methane and hydrogen. The potential to introduce gasification-based combined cycles comprising gas turbines and steam turbines to utilize black liquors and wood pellets also merits investigation. To perform such analysis, it is important to first build knowledge on expected synthesis gas composition by gasifying at smaller scale different types of feed stock. In the present paper, the synthesis gas quality from wood pellets gasification has been compared with black liquor gasification by means of numerical simulation as well as through pilot-scale experimental investigations. The experimental results have been correlated into partial least squares models to predict the composition of the synthesis gas produced under different operating conditions. The gas quality prediction models are combined with physical models using a generic open-source modelling language for investigating the dynamic performance of large-scale integrated polygeneration plants. The analysis is further complemented by considering potential gas separation using modern membrane technology for upgrading the synthesis gas with respect to hydrogen content. The experimental data and statistical models presented in this study form an important literature source for future use by the gasification and polygeneration research community on further integrated system analysis., QC 20171208

The GreenLight consortium is working to demonstrate a biobased, renewable and economically viable carbon fibre from lignin. The aim is to provide a basis for commercial production of lignin, lignin filaments, carbon fibre and carbon fibre composites. The most difficult boundary to success in the developing lignin as a precursor for continuous filament carbon fibre has been identified as melt extrusion of lignin. The consortium is working to develop a robust melt spinning platform for use up to the 1,000 filament scale. Methodical studies have been performed to examine lignin separation from differing black liquors derived from both softwood and hardwood and assess their viability in terms of thermal, compositional and structural properties. The move will then be made to pilot scale melt spinning at the 100 filament scale. The characteristics of some kraft lignin fractions obtained from the same Sodra Monsteras softwood kraft black liquor have been studied. The lignins were manufactured in quantities of approximately 10-20kg. Several variations of the LignoBoost process were used to provide lignins with improved melt spinning properties. The lignins were of high purity, each having low carbohydrate, extractives and inorganic contents. All four lignins could be melt spun and converted to carbon fibre.

There is a potential to integrate biomass gasification with pulp & paper and CHP plants in order to complement the existing systems with production of chemicals, such as methane, hydrogen, and methanol etc. To perform system analysis of such integration, it is important to gain knowledge of relevant input data on expected synthesis gas composition by gasifying different types of feed stock. In this paper, the synthesis gas quality from wood pellets gasification (WPG) has been compared with black liquor gasification (BLG) through modeling and experimental results at pilot scale. In addition, the study develops regression models like Partial Least Squares (PLS) made from the experimental data. The regression models are then combined with dynamic models developed in Modelica for the investigation of dynamic energy and material balances for integrated plants. The data presented in this study could be used as input to relevant analysis using e.g. ASPEN plus and similar system analysis tools., QC 20170629

Med mer och billigare förnybar, intermittent el på marknaden har intresset för elektrobränsle ökat. I denna studie utvärderas tekno-ekonomiskt om elektrobränslekoncept kan vara fördelaktigt att implementera i en förgasningsanläggning för svartlut med nedströms metanolsyntes. Detta görs genom jämförelse av tre möjliga integreringsalternativ: 1. Basfallet, att inte implementera någon elektrolysör. 2. Att implementera elektrolysör för att tillgodose vätgasunderskottet för metanolsyntes från kolmonoxid och därmed eliminera behovet av CO-shift. 3. Att implementera elektrolysör för att förse förgasare med syrgas, kompensera vätgasunderskottet för metanolsyntesen från kolmonoxid och samtidigt konvertera koldioxid till metanol. Genom detta elimineras behovet av både CO-shift och luftseparationsanläggning. För att utvärdera de olika fallen har en statisk modell som utgår från förgasningssimuleringar konstruerats. Modellen har sedan kompletterats med vätgas och syrgas från elektrolysör. Energi- och massbalanser har sedan legat till grund för dimensionering av processutrustning. En förgasningsanläggning på 500 ton svartlut torrsubstans per dygn har varit basen samt råvarupriser för biomassa på 0,2 kr/kWh och elpriser på 0,25 kr/kWh. För att få fram relevant data för elektrolysören har det tagits in offerter från tillverkare och diskussioner via telefon har förts för genomgång av offert för att hitta den bästa lösningen. Resultaten från den tekno-ekonomiska analysen presenteras som ett nödvändigt försäljningspris (NFP) för den producerade metanolen. Detta är framtaget utifrån en internränta på 10% och en ekonomisk livslängd på 20år. Resultaten visar att då det inte implementeras någon elektrolysör blir NFP 1,15 kr/kWh. Med implementerad elektrolysör för att tillgodose vätgasunderskottet fås en produktionsökning på 30% jämfört med basfallet och ett NFP på 1,12 kr/kWh. När elektrolysören dimensioneras mot syrgasbehovet fås en produktionsökning på 100% och ett NFP på 0,98 kr/kWh. De, With more and cheaper intermittent renewable electricity on the market, the interest in electro fuels is increasing. In this study, the techno economic performance of implementing electro fuel concept to a black liquor gasification plant with methanol synthesis is evaluated. This is done by studying three different ways of integration: 1. The base case, by not implementing an electrolyzer. 2. By implementing the electrolyzer to cover the deficit of hydrogen for synthesis of the carbon monoxide and thereby eliminate the need of CO-shift. 3. By implementing the electrolyzer to cover all the oxygen demand to the gasifier, compensate the deficit of hydrogen for synthesis of carbon monoxide while also converting carbon dioxide to methanol. This eliminates the need of CO-shift and air separation unit. To be able to evaluate the different cases, a static model that is based on gasification simulations was constructed. The model was then supplemented with hydrogen and oxygen from the electrolyzer. Energy and mass balances was then the base for dimensioning of the process equipment. A gasification plant of 500 tonnes ds/day has been the base in the evaluation as well as pricing for biomass on 0.2 kr/kWh and electricity on 0,25 kr/kWh. To extract relevant data, offers from manufactures have been requested and discussions regarding the offers have been held to find the best solution for implementation. The results from the techno economic evaluation are presented as the required selling price of the produced methanol. This is done on the condition of an internal rate of return on 10% and a lifetime of 20 years. The results of the study show that if no electrolyzer is used, the required selling price is 1,15 kr/kWh. With implemented electrolyzer to cover the deficit of hydrogen there is a production increase on 30% and a required selling price of 1,12 kr/kWh. When the electrolyzer is built to cover all the oxygen demand there is a production increase of 100% compared to the case without e

Carbon fiber is a lightweight, versatile material with many current and potential applications. To be able to expand the market for carbon fiber composites in other areas than special applications the production costs must be reduced. One way of accomplishing this could be to use a less expensive raw material where lignin is a good example as it can be provided at lower cost, is renewable and abundantly available compared to commercially used raw materials today. So far, the mechanical properties of lignin-based carbon fibers are inferior relative to commercial carbon fibers. For lignin-based carbon fibers to enter the commercial market more research is necessary to gain knowledge of the conversion of lignin to carbon fiber. The LightFibre project investigates the possibilities to produce carbon fibers based on a mixture of softwood kraft lignin and cellulose. The kraft lignin is isolated from black liquor in the kraft/sulfate process with the LignoBoost process. This master thesis project was conducted within in the LightFibre project and evaluated whether metal ions generally present in kraft lignin had an influence on the final carbon fiber quality in terms of mechanical properties and morphology. The mechanical properties were determined with tensile testing, the morphology by scanning electron microscopy (SEM) and the relative abundance of studied elements with electron dispersive spectroscopy (EDS). The influence of the chosen metal ions was tested by impregnation of dry-jet wet spun prefibers based on 70 wt.% softwood kraft lignin and 30 wt.% dissolving pulp cellulose. The fibers were impregnated in room temperature with solutions containing Na2SO4, K2SO4, MgSO4, FeSO4 and Al2(SO4)3 salts where the cations were the focus in these trials. The concentrations used for impregnation were 0.2 and 1M of the cations. The obtained mechanical properties of the carbon fibers of the samples impregnated with different metal ions did not deviate significantly from the refe

The aim of this report was to study possibilities of making the process of extracting lignin from black liquor at pulp and paper mills more efficient in the form of a literature study. Lignin is a commodity that is likely to become more valuable in the future due to work being done by a number of companies in utilizing it as for example a base for the production of renewable fuels and carbon fibre. At the current moment the extraction of lignin from black liquor is quite expensive so it is not yet common on an industrial scale thus it is important to find methods of reducing the costs. One of the more reliable methods of extracting lignin from black liquor is known as acid precipitation and involves utilizing mineral acids to lower the pH of the liquor and induce precipitation of solved lignin into a solid form. Normally carbon dioxide is used in the initial precipitation step where the pH is lowered to 8-9 and then sulfuric acid is added reducing the pH of the lignin further to 2.5-3. Introducing sulfuric acid into the process however will affect the sodium-sulfur balance in the mill and excess sulfur must be purged to avoid reducing the quality of the pulp. Sulfur is commonly purged in the form of dust from the electrostatic precipitator with this dust also containing sodium compounds. This will in turn reduce the sodium content in the mill calling for the demand of make-up sodium which costs quite a bit more than sulfuric acid. By choosing to utilize pre-existing process streams of sufur and carbon dioxide at the mill for use in acid precipitation one can potentially avoid additional chemical costs and avoid upsetting the sulfur balance. Thus the primary goal of this project has been to study the possibility of utilizing carbon dioxide at the mill for acid precipitation and determining a method of separating sulfuric compounds from black liquor and converting them into sulfuric acid. It was found that the required carbon dioxide could be supplied from flue gases, Today it is of great interest to lessen our dependency on fossil fuels. One product of untapped potential is lignin which has already sparked a great amount of interest as a base for the production of renewable fuels, in addition pure lignin has the potential to be used as a base for the production of carbon fibre. One noteworthy source of lignin that is not commonly used yet is in the pulp and paper industry. During the pulping process where cellulose fibres are separated from wood a liquid chemical by-product is formed which is known as black liquor. One major component of black liquor is lignin, this lignin in particular is unique as it is in a solved state and cannot be separated efficiently under normal conditions. By reducing the pH of black liquor through exposure to carbon dioxide and sulfuric acid however it is possible for the lignin to form a solid phase. Through filtration and washing it is possible to produce a solid lignin product that can then be utilized.

Med mer och billigare förnybar, intermittent el på marknaden har intresset för elektrobränsle ökat. I denna studie utvärderas tekno-ekonomiskt om elektrobränslekoncept kan vara fördelaktigt att implementera i en förgasningsanläggning för svartlut med nedströms metanolsyntes. Detta görs genom jämförelse av tre möjliga integreringsalternativ: 1. Basfallet, att inte implementera någon elektrolysör. 2. Att implementera elektrolysör för att tillgodose vätgasunderskottet för metanolsyntes från kolmonoxid och därmed eliminera behovet av CO-shift. 3. Att implementera elektrolysör för att förse förgasare med syrgas, kompensera vätgasunderskottet för metanolsyntesen från kolmonoxid och samtidigt konvertera koldioxid till metanol. Genom detta elimineras behovet av både CO-shift och luftseparationsanläggning. För att utvärdera de olika fallen har en statisk modell som utgår från förgasningssimuleringar konstruerats. Modellen har sedan kompletterats med vätgas och syrgas från elektrolysör. Energi- och massbalanser har sedan legat till grund för dimensionering av processutrustning. En förgasningsanläggning på 500 ton svartlut torrsubstans per dygn har varit basen samt råvarupriser för biomassa på 0,2 kr/kWh och elpriser på 0,25 kr/kWh. För att få fram relevant data för elektrolysören har det tagits in offerter från tillverkare och diskussioner via telefon har förts för genomgång av offert för att hitta den bästa lösningen. Resultaten från den tekno-ekonomiska analysen presenteras som ett nödvändigt försäljningspris (NFP) för den producerade metanolen. Detta är framtaget utifrån en internränta på 10% och en ekonomisk livslängd på 20år. Resultaten visar att då det inte implementeras någon elektrolysör blir NFP 1,15 kr/kWh. Med implementerad elektrolysör för att tillgodose vätgasunderskottet fås en produktionsökning på 30% jämfört med basfallet och ett NFP på 1,12 kr/kWh. När elektrolysören dimensioneras mot syrgasbehovet fås en produktionsökning på 100% och ett NFP på 0,98 kr/kWh. De, With more and cheaper intermittent renewable electricity on the market, the interest in electro fuels is increasing. In this study, the techno economic performance of implementing electro fuel concept to a black liquor gasification plant with methanol synthesis is evaluated. This is done by studying three different ways of integration: 1. The base case, by not implementing an electrolyzer. 2. By implementing the electrolyzer to cover the deficit of hydrogen for synthesis of the carbon monoxide and thereby eliminate the need of CO-shift. 3. By implementing the electrolyzer to cover all the oxygen demand to the gasifier, compensate the deficit of hydrogen for synthesis of carbon monoxide while also converting carbon dioxide to methanol. This eliminates the need of CO-shift and air separation unit. To be able to evaluate the different cases, a static model that is based on gasification simulations was constructed. The model was then supplemented with hydrogen and oxygen from the electrolyzer. Energy and mass balances was then the base for dimensioning of the process equipment. A gasification plant of 500 tonnes ds/day has been the base in the evaluation as well as pricing for biomass on 0.2 kr/kWh and electricity on 0,25 kr/kWh. To extract relevant data, offers from manufactures have been requested and discussions regarding the offers have been held to find the best solution for implementation. The results from the techno economic evaluation are presented as the required selling price of the produced methanol. This is done on the condition of an internal rate of return on 10% and a lifetime of 20 years. The results of the study show that if no electrolyzer is used, the required selling price is 1,15 kr/kWh. With implemented electrolyzer to cover the deficit of hydrogen there is a production increase on 30% and a required selling price of 1,12 kr/kWh. When the electrolyzer is built to cover all the oxygen demand there is a production increase of 100% compared to the case without e

Carbon fiber is a lightweight, versatile material with many current and potential applications. To be able to expand the market for carbon fiber composites in other areas than special applications the production costs must be reduced. One way of accomplishing this could be to use a less expensive raw material where lignin is a good example as it can be provided at lower cost, is renewable and abundantly available compared to commercially used raw materials today. So far, the mechanical properties of lignin-based carbon fibers are inferior relative to commercial carbon fibers. For lignin-based carbon fibers to enter the commercial market more research is necessary to gain knowledge of the conversion of lignin to carbon fiber. The LightFibre project investigates the possibilities to produce carbon fibers based on a mixture of softwood kraft lignin and cellulose. The kraft lignin is isolated from black liquor in the kraft/sulfate process with the LignoBoost process. This master thesis project was conducted within in the LightFibre project and evaluated whether metal ions generally present in kraft lignin had an influence on the final carbon fiber quality in terms of mechanical properties and morphology. The mechanical properties were determined with tensile testing, the morphology by scanning electron microscopy (SEM) and the relative abundance of studied elements with electron dispersive spectroscopy (EDS). The influence of the chosen metal ions was tested by impregnation of dry-jet wet spun prefibers based on 70 wt.% softwood kraft lignin and 30 wt.% dissolving pulp cellulose. The fibers were impregnated in room temperature with solutions containing Na2SO4, K2SO4, MgSO4, FeSO4 and Al2(SO4)3 salts where the cations were the focus in these trials. The concentrations used for impregnation were 0.2 and 1M of the cations. The obtained mechanical properties of the carbon fibers of the samples impregnated with different metal ions did not deviate significantly from the refe

The aim of this report was to study possibilities of making the process of extracting lignin from black liquor at pulp and paper mills more efficient in the form of a literature study. Lignin is a commodity that is likely to become more valuable in the future due to work being done by a number of companies in utilizing it as for example a base for the production of renewable fuels and carbon fibre. At the current moment the extraction of lignin from black liquor is quite expensive so it is not yet common on an industrial scale thus it is important to find methods of reducing the costs. One of the more reliable methods of extracting lignin from black liquor is known as acid precipitation and involves utilizing mineral acids to lower the pH of the liquor and induce precipitation of solved lignin into a solid form. Normally carbon dioxide is used in the initial precipitation step where the pH is lowered to 8-9 and then sulfuric acid is added reducing the pH of the lignin further to 2.5-3. Introducing sulfuric acid into the process however will affect the sodium-sulfur balance in the mill and excess sulfur must be purged to avoid reducing the quality of the pulp. Sulfur is commonly purged in the form of dust from the electrostatic precipitator with this dust also containing sodium compounds. This will in turn reduce the sodium content in the mill calling for the demand of make-up sodium which costs quite a bit more than sulfuric acid. By choosing to utilize pre-existing process streams of sufur and carbon dioxide at the mill for use in acid precipitation one can potentially avoid additional chemical costs and avoid upsetting the sulfur balance. Thus the primary goal of this project has been to study the possibility of utilizing carbon dioxide at the mill for acid precipitation and determining a method of separating sulfuric compounds from black liquor and converting them into sulfuric acid. It was found that the required carbon dioxide could be supplied from flue gases, Today it is of great interest to lessen our dependency on fossil fuels. One product of untapped potential is lignin which has already sparked a great amount of interest as a base for the production of renewable fuels, in addition pure lignin has the potential to be used as a base for the production of carbon fibre. One noteworthy source of lignin that is not commonly used yet is in the pulp and paper industry. During the pulping process where cellulose fibres are separated from wood a liquid chemical by-product is formed which is known as black liquor. One major component of black liquor is lignin, this lignin in particular is unique as it is in a solved state and cannot be separated efficiently under normal conditions. By reducing the pH of black liquor through exposure to carbon dioxide and sulfuric acid however it is possible for the lignin to form a solid phase. Through filtration and washing it is possible to produce a solid lignin product that can then be utilized.

The GreenLight consortium is working to demonstrate a biobased, renewable and economically viable carbon fibre from lignin. The aim is to provide a basis for commercial production of lignin, lignin filaments, carbon fibre and carbon fibre composites. The most difficult boundary to success in the developing lignin as a precursor for continuous filament carbon fibre has been identified as melt extrusion of lignin. The consortium is working to develop a robust melt spinning platform for use up to the 1,000 filament scale. Methodical studies have been performed to examine lignin separation from differing black liquors derived from both softwood and hardwood and assess their viability in terms of thermal, compositional and structural properties. The move will then be made to pilot scale melt spinning at the 100 filament scale. The characteristics of some kraft lignin fractions obtained from the same Sodra Monsteras softwood kraft black liquor have been studied. The lignins were manufactured in quantities of approximately 10-20kg. Several variations of the LignoBoost process were used to provide lignins with improved melt spinning properties. The lignins were of high purity, each having low carbohydrate, extractives and inorganic contents. All four lignins could be melt spun and converted to carbon fibre.

There is a potential to integrate biomass gasification with pulp & paper and CHP plants in order to complement the existing systems with production of chemicals, such as methane, hydrogen, and methanol etc. To perform system analysis of such integration, it is important to gain knowledge of relevant input data on expected synthesis gas composition by gasifying different types of feed stock. In this paper, the synthesis gas quality from wood pellets gasification (WPG) has been compared with black liquor gasification (BLG) through modeling and experimental results at pilot scale. In addition, the study develops regression models like Partial Least Squares (PLS) made from the experimental data. The regression models are then combined with dynamic models developed in Modelica for the investigation of dynamic energy and material balances for integrated plants. The data presented in this study could be used as input to relevant analysis using e.g. ASPEN plus and similar system analysis tools.

It is vital to perform system analysis on integrated biomass gasification in chemical recovery systems in pulp and paper and heat and power plants for polygeneration applications. The proposed integration complements existing pulp and paper and heat and power production systems with production of chemicals such as methane and hydrogen. The potential to introduce gasification-based combined cycles comprising gas turbines and steam turbines to utilize black liquors and wood pellets also merits investigation. To perform such analysis, it is important to first build knowledge on expected synthesis gas composition by gasifying at smaller scale different types of feed stock. In the present paper, the synthesis gas quality from wood pellets gasification has been compared with black liquor gasification by means of numerical simulation as well as through pilot-scale experimental investigations. The experimental results have been correlated into partial least squares models to predict the composition of the synthesis gas produced under different operating conditions. The gas quality prediction models are combined with physical models using a generic open-source modelling language for investigating the dynamic performance of large-scale integrated polygeneration plants. The analysis is further complemented by considering potential gas separation using modern membrane technology for upgrading the synthesis gas with respect to hydrogen content. The experimental data and statistical models presented in this study form an important literature source for future use by the gasification and polygeneration research community on further integrated system analysis. (C) 2017 Elsevier Ltd. All rights reserved.

The last couple of decades have seen entrained-flow gasification of black liquor (BL) undergo an incremental process of technical development as an alternative to combustion in a recovery boiler. The ability of the technology to combine chemical recovery with the production of clean syngas renders it a promising candidate for the transformation of chemical pulp mills into integrated forest biorefineries. However, techno-economic assessments have shown that blending BL with the more easily transportable pyrolysis oil (PO) can not only increase the system efficiency for methanol production but remove a significant roadblock to development by partially decoupling production capacity from limitations on black liquor availability. The verification and study of catalytic co-gasification in an industrially-relative scale can yield both scientifically interesting and practically useful results, yet it is a costly and time-consuming enterprise. The expense and time involved can be significantly reduced by performing thermodynamic equilibrium calculations using a model that has been validated with relevant experimental data. The main objective of this thesis was to study, understand, quantify and compare the gasification behaviour and process performance of black liquor and pyrolysis oil blends in pilot-scale. A secondary objective of this work was to demonstrate and assess the usefulness and accuracy of unconstrained thermodynamic equilibrium modelling as a tool for studying and predicting the characteristics of alkali-impregnated biomass entrained-flow gasification. The co-gasification of BL/PO blends was studied at the 3 MWth LTU Green Fuels pilot plant in a series of experimental studies between June 2015 and April 2016. The results of the studies showed that the blending of black liquor with the more energy rich pyrolysis oil increased the energetic efficiency of the BLG process without adversely affecting carbon conversion. The effect of blend ratio and reactor temperat, LTU Biosyngas (Catalytic Gasification)

The use and research of renewable fuels has become more important due to the connection between climate changes and the use of fossil fuels. With risks of decline in petroleum production derived from fossil fuels due to limitation of resources in the future, the renewable fuels are even more important in the transport sector. Research regarding gasification of biomass to create a syngas that can be upgraded to a biodiesel for cars is one of the approaches. By gasifying black liquor, it is possible to create a 100 % green fuel diesel. However, as this black liquor might be in limited quantities the idea to create a synthetic black liquor was sparked. The pulp industry where the black liquor originated from also has quantities of wastewater, containing a biomass sludge. Otherwise containing water in so large quantities that it is not possible to combust it without ending up with a negative energy output. One of the paths could be to recover the biomass from the sludge and convert it to a liquid similar to black liquor. Catalytic hydrothermal liquefaction has been recognized as a potential method. While biocrude is usually the target in hydrothermal liquefaction for direct upgrade to biofuel, the aqueous product could prove to be used for the gasification process. This would create a combined liquefaction-gasification process. Using model compounds possibly existing in the waste sludge, hydrothermal liquefaction was performed at different temperatures, together with varied alkali loads (K2CO3) and water the content to see how the different compounds reacted. Model compounds included cellulose and lignin as major compounds. Although the temperature was increased from 240 °C to 340 ° the lignin conversion was lower at 340 °C than at 240 °C. Re-polymerization took place and around 40 % of resulted in solid residue, while the remaining 60 % was partially converted to aqueous phase, oil phase or gas in the process. By not performing the hydrothermal liquefaction it is howev

The use and research of renewable fuels has become more important due to the connection between climate changes and the use of fossil fuels. With risks of decline in petroleum production derived from fossil fuels due to limitation of resources in the future, the renewable fuels are even more important in the transport sector. Research regarding gasification of biomass to create a syngas that can be upgraded to a biodiesel for cars is one of the approaches. By gasifying black liquor, it is possible to create a 100 % green fuel diesel. However, as this black liquor might be in limited quantities the idea to create a synthetic black liquor was sparked. The pulp industry where the black liquor originated from also has quantities of wastewater, containing a biomass sludge. Otherwise containing water in so large quantities that it is not possible to combust it without ending up with a negative energy output. One of the paths could be to recover the biomass from the sludge and convert it to a liquid similar to black liquor. Catalytic hydrothermal liquefaction has been recognized as a potential method. While biocrude is usually the target in hydrothermal liquefaction for direct upgrade to biofuel, the aqueous product could prove to be used for the gasification process. This would create a combined liquefaction-gasification process. Using model compounds possibly existing in the waste sludge, hydrothermal liquefaction was performed at different temperatures, together with varied alkali loads (K2CO3) and water the content to see how the different compounds reacted. Model compounds included cellulose and lignin as major compounds. Although the temperature was increased from 240 °C to 340 ° the lignin conversion was lower at 340 °C than at 240 °C. Re-polymerization took place and around 40 % of resulted in solid residue, while the remaining 60 % was partially converted to aqueous phase, oil phase or gas in the process. By not performing the hydrothermal liquefaction it is howev

The last couple of decades have seen entrained-flow gasification of black liquor (BL) undergo an incremental process of technical development as an alternative to combustion in a recovery boiler. The ability of the technology to combine chemical recovery with the production of clean syngas renders it a promising candidate for the transformation of chemical pulp mills into integrated forest biorefineries. However, techno-economic assessments have shown that blending BL with the more easily transportable pyrolysis oil (PO) can not only increase the system efficiency for methanol production but remove a significant roadblock to development by partially decoupling production capacity from limitations on black liquor availability. The verification and study of catalytic co-gasification in an industrially-relative scale can yield both scientifically interesting and practically useful results, yet it is a costly and time-consuming enterprise. The expense and time involved can be significantly reduced by performing thermodynamic equilibrium calculations using a model that has been validated with relevant experimental data. The main objective of this thesis was to study, understand, quantify and compare the gasification behaviour and process performance of black liquor and pyrolysis oil blends in pilot-scale. A secondary objective of this work was to demonstrate and assess the usefulness and accuracy of unconstrained thermodynamic equilibrium modelling as a tool for studying and predicting the characteristics of alkali-impregnated biomass entrained-flow gasification. The co-gasification of BL/PO blends was studied at the 3 MWth LTU Green Fuels pilot plant in a series of experimental studies between June 2015 and April 2016. The results of the studies showed that the blending of black liquor with the more energy rich pyrolysis oil increased the energetic efficiency of the BLG process without adversely affecting carbon conversion. The effect of blend ratio and reactor temperat, LTU Biosyngas (Catalytic Gasification)

The primary objective of this study was to quantify the amount of excess energy that is present in the evaporation system of an integrated pulp and paper-board mill and to analyze a number of energy recovery cases. These focus on improving the energy efficiency in the evaporation plant and are mainly based on the process data of performance tests from the full-scale production site. A computer script was developed in order to analyze the process streams and can be used to construct the Grand Composite Curve (GCC) of the evaporation system. In addition, the study identified seasonal variations in the potential excess of energy (higher in warmer weather and lower, or even non-existent, in colder) and suggestions are made as to how this energy may be used in a thermodynamically optimal way. In the case studies, the thermodynamically optimal method of recovering heat involved a combination of sensible heat and flash evaporation, indicating the maximum reduction in steam consumption. For the case of only utilizing sensible heat outside the evaporator system to pre-heat one of the liquor flows, the results indicated a lower reduction in steam but also a lower capital cost.

The energy situation in both process industries andpower plants is changing. It is becoming interesting toperform system analysis on how to integrate gasificationinto chemical recovery systems in the pulp & paperindustry and into the CHP systems in power plantapplications to complement with production ofchemicals aside of heat and power. The potentialchemicals are methane, hydrogen, and methanol. It isalso interesting to estimate the potential to introducecombined cycles with gas turbines and steam turbinesusing both black liquors and other type of biomass likepellets, wood chips etc. To perform such type ofanalysis, it is vital to have relevant input data on whatgas composition we can expect from running differenttypes of feedstock. In this paper, we focus on blackliquors as feedstock for integrated gasification systems.The experimental results are correlated into partial leastsquares models to predict major composition of thesynthesis gas produced under different conditions.These quality prediction models are then combined withphysical models using Modelica for the investigation ofdynamic energy and material balances for completeplants. The data can also be used as input to analysisusing e.g. ASPEN plus and similar system analysistools

Neprocesní prvky v sulfátové celulózce mají negativní vliv na regenerační cyklus varných chemikálií. Vzhledem k omezenému počtu výstupních míst je nutná kvantitativní kontrola těchto prvků ve významných vnitřních a výstupních proudech. Náplní diplomové práce je proměření obsahu manganu, hořčíku, železa, hliníku a vápníku v důležitých proudech, vytvoření bilancí jednotlivých prvků. Mondi Štětí a.s. používá od roku 2015 nové zařízení na filtraci zeleného louhu, a jelikož nejdůležitějším výstupním proudem neprocesních prvků je odvod kalu po filtraci zeleného louhu, byly naměřené hodnoty porovnány s předchozími lety., ANNOTATION Non-process elements have a negative impact on the recovery cycle of cooking chemicals in the kraft pulp. Due to the limited number of exit points a quantitative control of these elements in significant internal and output streams is necessary. The master thesis deals with the measurement of manganese, magnesium, iron, aluminium and calcium content in important streams, and established the balances of the individual elements. Mondi Štětí a.s. has been using new facilities for the filtration of green liquor since 2015. In view of the fact that the most important output stream of the non-process elements is the sludge from the filtered green liquor (dregs), the measured values are compared with previous years., Fakulta chemicko-technologická

The mycelial growth ability of 13 white rot fungi were separately evaluated in kraft, organosolv, and soda black liquor agar-plates. The fungus able to best grow and decolorize black liquor agar-plates was grown in organosolv black liquor to investigate whether it reduced organosolv lignin molar mass. The fungus Bjerkandera adusta showed fair mycelial growth and decolorization ability in 10% black liquor-agar plates. To obtain low-molecular weight (MW) lignin, B. adusta was cultivated in 150-mL Erlenmeyer flasks containing 10% black liquor and maintained in a shaking culture for 15 days. Lignin was recovered from each Erlenmeyer flask by acid precipitation and was analysed by size exclusion chromatography (SEC) and Fourier transform infrared (FTIR) spectroscopy. The lowest MW of lignin from black liquor was observed on the 11th and 12th days, at 1461 and 1790 kDa, respectively, with the polydispersity close to 1.0, indicating that the molecules were similar in size. Fourier transform infrared spectra bands showed modification of the lignin structure during 9 days, with new bands appearing after five days of lignin biodegradation.

The mycelial growth ability of 13 white rot fungi were separately evaluated in kraft, organosolv, and soda black liquor agar-plates. The fungus able to best grow and decolorize black liquor agar-plates was grown in organosolv black liquor to investigate whether it reduced organosolv lignin molar mass. The fungus Bjerkandera adusta showed fair mycelial growth and decolorization ability in 10% black liquor-agar plates. To obtain low-molecular weight (MW) lignin, B. adusta was cultivated in 150-mL Erlenmeyer flasks containing 10% black liquor and maintained in a shaking culture for 15 days. Lignin was recovered from each Erlenmeyer flask by acid precipitation and was analysed by size exclusion chromatography (SEC) and Fourier transform infrared (FTIR) spectroscopy. The lowest MW of lignin from black liquor was observed on the 11th and 12th days, at 1461 and 1790 kDa, respectively, with the polydispersity close to 1.0, indicating that the molecules were similar in size. Fourier transform infrared spectra bands showed modification of the lignin structure during 9 days, with new bands appearing after five days of lignin biodegradation.

Towards a bio-economy: the role of the forest Biomass has an increasingly important role in replacing fossil and mineral resources, and it is central in environmental impact-reduction strategies in companies and governments, locally, nationally and internationally. The European Union (EU) has recently taken action to strengthen the bio-economy, defined as “…the sustainable production and conversion of biomass into a range of food, health, fibre and industrial products and energy”. Two thirds of the land area in Sweden is covered by forests, and forestry has been an important industry for centuries. Increased and/or more efficient use of forest biomass thus has a great potential for replacing the use of fossil and mineral resources in Sweden. There are two main reasons for why forest- and other bio-based products are seen as environmentally beneficial. Biomass is (most often) a renewable resource, in contrast to finite fossil and mineral resources, and there is often a balance between CO2 captured when the biomass grows, and CO2 released when the bio-based product is incinerated. The challenge: calculate carbon footprints Moving towards a bio-economy means replacing non-renewable fuels and materials with bio-based fuels and materials. This is a transition on many levels: technology, business models, infrastructure, political priorities, etc. To guide such a grand transition, there is a need to understand the environmental implications of new bio-based products. This includes assessing their climate impact, so-called carbon footprinting. Carbon footprinting of forest products is not as simple as saying that forest products are carbon and climate neutral by definition. Fossil energy used for producing and transporting the products has a carbon footprint. Also, the carbon balance can differ between forest products, which can influence their carbon footprint. For example, carbon stored in products, while CO2 is captured in the re-growing forest, can mitigate climate chan, The method’s influence on climate impact assessment of biofuels and other uses of forest biomass

Precipitation and utilization of lignin from black liquor (BL) offers many promising advantages to modern kraft pulp mills. A novel process, known as "LignoBoost", has recently been introduced as a process for separating lignin from BL; it results in lignins with a low ash and high dry solid content. There is a lack of knowledge regarding the influences of process parameters on the behavior of lignin in the precipitation step. In this study, the yield of precipitated lignin and its average molecular weight (MWt) and carbohydrate content were the focus. Nuclear magnetic resonance (NMR) analysis showed that the lignin yield increased at lower pH and temperatures or when the ion strength of BL was elevated. High yield lignins contained more low MWt components and such lignins have more phenolic OH and methoxy groups. Xylan content of the lignins decreased with decreasing pH and increasing temperature, but glucomannan content was virtually unaffected by the conditions of precipitation., QC 20150323

Black liquor (BL) gasification is a proven process with very low tar generation at lower temperature than other entrained-flow biomass gasification processes. Recently, BL gasification technology was further expanded to increase feedstock flexibility by co-gasifying pyrolysis oil (PO) with BL. Economic advantage was shown by a techno-economic study. Our previous lab-scale studies using a thermo-gravimetric analyzer and a flat flame burner showed high char reactivity of sample mixture (30wt.% blend of PO into BL) as alkali content in BL kept high catalytic activity despite being diluted by the addition of PO. However, tar and soot formation from this new feedstock remained unknown. In this study, we investigated how the reaction conditions affect the formation of tar and soot to understand their formation mechanism and to suggest suitable operation conditions for the industrial processes. Experiments were carried out with fuel blends containing between 0 and 40wt.% of PO in BL using a laminar entrained flow reactor under the flow of N2/CO2. The effects of operating parameters were evaluated by varying temperature (1073-1673 K), partial pressure of CO2 (0-20 kPa), particle size (90-200 μm and 500-630 μm) and residence time. High temperature (i.e. 1673 K), high heating rate and short residence time experiments were performed to mimic industrial-scale conditions. Soot yield was under detection limit while low amounts of tar (mainly benzene) were formed at low temperature and decreased as the temperature increased. Addition of PO maintained the yields of tar and soot very low while it increased the syngas yield. Overall, this study demonstrated the feasibility of co-gasification of PO and BL and provided valuable information about tar formation under different operating conditions., Godkänd; 2015; 20160524 (albbac)

Black liquor (BL) gasification is a proven process with very low tar generation at lower temperature than other entrained-flow biomass gasification processes. Recently, BL gasification technology was further expanded to increase feedstock flexibility by co-gasifying pyrolysis oil (PO) with BL. Economic advantage was shown by a techno-economic study. Our previous lab-scale studies using a thermo-gravimetric analyzer and a flat flame burner showed high char reactivity of sample mixture (30wt.% blend of PO into BL) as alkali content in BL kept high catalytic activity despite being diluted by the addition of PO. However, tar and soot formation from this new feedstock remained unknown. In this study, we investigated how the reaction conditions affect the formation of tar and soot to understand their formation mechanism and to suggest suitable operation conditions for the industrial processes. Experiments were carried out with fuel blends containing between 0 and 40wt.% of PO in BL using a laminar entrained flow reactor under the flow of N2/CO2. The effects of operating parameters were evaluated by varying temperature (1073-1673 K), partial pressure of CO2 (0-20 kPa), particle size (90-200 μm and 500-630 μm) and residence time. High temperature (i.e. 1673 K), high heating rate and short residence time experiments were performed to mimic industrial-scale conditions. Soot yield was under detection limit while low amounts of tar (mainly benzene) were formed at low temperature and decreased as the temperature increased. Addition of PO maintained the yields of tar and soot very low while it increased the syngas yield. Overall, this study demonstrated the feasibility of co-gasification of PO and BL and provided valuable information about tar formation under different operating conditions., Godkänd; 2015; 20160524 (albbac)

A new approach using reed pulping black liquor by hydrothermal reaction followed by fast carbonization at 350 °C in fluidized bed reactor for 5 minutes was proposed in this paper. The BET specific surface area generated at optimum conditions reached 390 m2 g–1. The CO2 selectivity over CH4 and N2 comparable to commercial activated carbons was obtained. The isosteric enthalpies of adsorption for CO2, CH4 and N2 on the resultant carbon sample prepared at optimum conditions show surface heterogeneity. The kinetic results indicate its potential for separation of carbon dioxide from carbon dioxide/methane mixture.

The increased use of fossil fuels during the last centuries has caused elevated levels of carbon dioxide in the atmosphere. There is significant evidence that this is the cause of global warming. To mitigate the global warming, measures has to be taken to use renewable fuels and make processes more efficient. Catalytic gasification and downstream upgrading of synthesis gas is a promising technology for biofuel production, where previous research in black liquor gasification is currently expanding into a wider fuel feedstock. This work focuses on co-gasification of black liquor and by-products from other biofuel production technologies. The interesting by-products were crude glycerol from biodiesel production and spruce fermentation residue from ethanol production. The main goals were to study if the fuels can mix homogeneously and study the char reactivity. CO2 char gasification for mixtures of black liquor and glycerol or fermentation residue respectively was studied using thermogravimetric analysis (TGA) for four temperatures between 750°C and 900°C. The results show that glycerol can be mixed in all proportions with black liquor and indicate that the char reactivity is unchanged. The sustained char reactivity for blends is attributed to the volatility of glycerol. The fermentation residue does not produce a homogeneous mixture with black liquor and the char is less reactive. More studies should be performed to further elucidate the validity of the results.