Bio-refining method

Abstract

The invention relates to a method of processing nitrogen and / or ash rich carbonaceous material(-s) into a first liquid product enriched in nitrogen and / or ash compounds and a second bio-oil product comprising the steps of: fractionating the carbonaceous material into a liquid product enriched in nitrogen and / or ash compounds and a residual carbonaceous material depleted in nitrogen and / or ash, and converting the residual carbonaceous material in a thermochemical conversion process at pressures in the range 10 to 400 bar and temperatures in the range 280 to 500 °C and recovering bio-oil from the converted residual carbonaceous material.

Description

[0001] Bio-refining method

[0002] Field of the invention

[0003] The present invention relates to the area of production of advanced liquid biofuels and chemicals, and other valuable by-products from carbonaceous residues. More specifically the invention relates to an improved method for conversion of nitrogen and / or ash rich carbonaceous material(-s) to a first liquid product enriched in nitrogen and / or ash compounds and a second product comprising a bio-oil.

[0004] Background of the invention

[0005] Advanced liquid biofuels and biochemicals produced from carbonaceous materials such as biomass and residue streams have become a central focus to mitigate global climate change arising from greenhouse gas emissions to develop sustainable circular economies.

[0006] Several candidate carbonaceous material(-s) are rich in nitrogen and / or ash which limits their use in processes for production of advanced liquid biofuels due to processing issues, efficiency losses and / or more complicated upgrading to finished fuels.

[0007] For example, carbonaceous materials having a high nitrogen content often results in a high emulsifying tendency of the bio-oil, which in a number of processes leads to more difficult product separation e.g., of water and ash from the bio-oil. Further, whereas the nitrogen content of the bio-oil produced is typically reduced compared to the nitrogen content in the unconverted carbonaceous material, a higher nitrogen content in the bio-oil produced by the process typically results when nitrogen rich carbonaceous materials are processed. A high nitrogen in the bio-oil produced often limits its options for direct use e.g., combustion applications or in marine engines due to increased NOx emissions. Therefore further downstream processing such as by hydro- processing for reduction of the nitrogen content of the bio-oil is typically required. It is further well known that nitrogen in crude oils is generally more difficult to remove in such hydro-processing processes than oxygen and typically requires more severe conditions. Hence, it is desirable to reduce the nitrogen content provided in the to avoid such issues.

[0008] Some candidate carbonaceous materials may have or further have a high ash content that may lead to process challenges such as increased wear of equipment and pipes due to erosion and / or may result in increased fouling of process pipes and equipment such as heat exchangers and / or a more difficult product separation and purification, which may lead to lower overall product yields and / or reduced quality of the bio-oil product and / or by-products, which makes such high ash containing feedstock less attractive.

[0009] Hence, it is desirable to be able to reduce the nitrogen and / or ash content of carbonaceous materials containing high amounts of nitrogen and / or ash, to provide improved and more efficient schemes for production of bio-oil and other valuable products from such nitrogen and ash containing carbonaceous materials.

[0010] Objective of the invention

[0011] Hence, the object of the present invention is therefore to provide an improved method for producing bio-oil from nitrogen and / or ash containing carbonaceous materials, which process is more efficient and is leading to improvements, such as resulting in a lower carbon intensity of the bio-oil and / or have a higher onstream factor and / or results in better resource utilization, i.e., with a higher degree of circularity.

[0012] Description of the invention

[0013] According to one aspect of the present invention, the objective of the invention is achieved through a method of processing nitrogen and / or ash rich carbonaceous material(-s) into a first liquid product enriched in nitrogen and / or ash compounds and a second bio-oil product comprising the steps of fractionating the carbonaceous material into a liquid product enriched in nitrogen and / or ash compounds and a residual carbonaceous material depleted in nitrogen and / or ash, and converting the residual carbonaceous material in a thermochemical conversion process at pressures in the range 10 to 400 bar and temperatures in the range 280 to 500 °C and recovering bio-oil from the converted carbonaceous material.

[0014] A carbonaceous material according to the present invention is generally a carbon containing material e.g. organic matter such as biomass and / or waste materials.

[0015] A nitrogen rich and / or ash rich carbonaceous material in the present context is understood as a carbonaceous material having a nitrogen content of more than 0,8 % by weight of the dry ash free carbonaceous material and / or a carbonaceous material having an ash content of more than 3 % by the dry weight of the carbonaceous material.

[0016] The carbonaceous material may in some embodiments have a nitrogen content of more than 1 ,0 % by weight of the dry ash free carbonaceous material, more than 1 ,25 % by weight of the dry ash free carbonaceous material, more than 1 ,5 % by weight of the dry ash free carbonaceous material, more than 2,0 % by weight of the dry ash free carbonaceous material and even more than 3,0 % by weight of the dry ash free carbonaceous material such as more than 4 % by weight of the dry ash free carbonaceous material.

[0017] The carbonaceous material may in some embodiments have an ash content of more than 4 % by weight of the dry carbonaceous material, more than 5 % by weight of the dry carbonaceous material, more than 6 % by weight of the dry carbonaceous material, more than 7 % by weight of the dry carbonaceous material and even more than 10 % by weight of the dry carbonaceous material such as more than 15 % by weight of the dry carbonaceous material such as more than 20 % by weight of the dry carbonaceous material.

[0018] Advantageously the step of fractionating the carbonaceous material (step a) comprises contacting the carbonaceous material with a solvent at a temperature of 40 to 180 °C such as a temperature in the range 40 to 90 °C or 40 to 70 °C.

[0019] In one embodiment the solvent in the step of fractionating the carbonaceous material comprises an alkaline solvent and the pH during the fractionation (step a) is maintained in the range 7 to 12.

[0020] In many preferred embodiments the solvent comprises sodium hydroxide and / or potassium hydroxide.

[0021] In another embodiment the solvent comprises an acidic solvent and pH during the fractionation is maintained in the range 2 to 6 such as a pH in the range 4 to 6.

[0022] In many embodiments according to the invention the acidic solvent comprises sulphuric acid, acetic acid, hydrochloric acid, citric acid, oxalic acid, or a combination thereof.

[0023] In some embodiments the solvent comprises or further comprises an organic solvent and / or a pH buffering solution such as phosphate-buffered saline (PBS) or Tris-HCI buffering solution.

[0024] In some applications of the present invention, the fractionation step (a) comprises or further comprises an enzymatic treatment step, where the carbonaceous material or residual carbonaceous material from the first fractionation is subjected to an enzymatic treatment to further reduce the nitrogen and / or ash content.

[0025] In one embodiment the enzymes used in the enzymatic treatment comprise proteases.

[0026] Often the temperature of enzymatic treatment is in the range 40 to 70 °C.

[0027] In some preferred applications the fractionation step (a) comprises a first fractionation using an alkaline solvent followed second fractionation step where the residual carbonaceous material from the alkaline fractionation step Is treated using an acidic solvent.

[0028] In other applications the fractionation step (a) comprises a first fractionation using an acidic solvent followed second fractionation step where the residual carbonaceous material from the acidic fractionation step is treated using an alkaline solvent.

[0029] Typically, the first liquid product(-s) from the fractionation step enriched in nitrogen and / or ash compounds is further subjected to one or more steps comprising a filtration, a centrifugation, a precipitation, an ion exchange and / or a chromatographic technique or a combination thereof for concentration and / or purification of the liquid product(-s).

[0030] In some embodiments the liquid products from the fractionation step enriched in nitrogen and / or ash compounds may be subjected or further subjected to a microfiltration and / or an ultrafiltration step to further concentrate and / or purify the product(-s). The conversion of the residual material from the fractionation step (b) is generally performed in a pressurized process such as at a pressure of at least 10 bar.

[0031] In many embodiments of the invention the pressure in the conversion step (b) is maintained in the range 20 bar below to 20 bar above the critical pressure of the fluid mixture.

[0032] Advantageously the conversion step (b) is performed at pressures above the boiling point of pressure of the fluid mixture to maintain the fluid mixture in a liquid or supercritical state. For clarity this is fulfilled by maintaining the pressure above the ciritical pressure of the fluid mixture when the temperature is above the critical temperature.

[0033] The temperature in the conversion step (b) is in many embodiments at least 300 °C such as at least 310 °C. Preferably the temperature in the conversion step (b) is at least 320 °C such as a temperature of at least 350 °C.

[0034] In many preferred embodiments the temperature for conversion of the residual carbonaceous material in the conversion step (b) is less than 450 °C such as a temperature of less than 400 °C, less than 385 °C, less than 370 °C or less then 360 °C.

[0035] In a preferred embodiment the conversion of the residual carbonaceous material in the conversion step (b) is performed in the presence of phenolics in a concentration of at least 2 % by weight such as at least 3 % by weight.

[0036] In another preferred embodiment the conversion of the residual carbonaceous material in the conversion step (b) is performed in the presence of one or more alcohols and / or polyols in a concentration of at least 5 % by weight. The phenolics in the conversion step of the residual carbonaceous material is according to particularly preferred embodiments produced from a renewable source, whereby the carbon footprint of the oil is further reduced.

[0037] In an advantageous embodiment the phenolics used in the conversion step (b) is produced by the process.

[0038] In one embodiment the phenolics is provided by recycling part of the oil produced by the process.

[0039] In another embodiment the phenolics are produced by conversion of a lignocellulosic material in the presence of phenolics and one or more alcohols and an acid at conversion temperatures in the range 160 to 260 °C and conversion pressures in the range 5 to 90 bar in a separate conversion step. In some embodiments the lignocellulosic material may comprise the residual carbonaceous material from the fractionation step.

[0040] In one embodiment of the invention the alcohol comprises methanol and / or ethanol.

[0041] The process gas produced by the conversion process of the residual carbonaceous material comprises carbon oxides such as carbon mono oxide as the main compounds. In an advantageous embodiment the one or more alcohol(-s) added to conversion step (b) is produced from the gas extracted from the converted residual carbonaceous material by reacting the gas with hydrogen in a catalytic reaction step. Often said catalytic reaction step is performed at pressures in the range 30 to 150 bar and temperatures in the range 200 to 450 °C such as at pressures in the range 50 to 100 bar and temperatures in the range 200 to 300 °C. The concentration of nitrogen in the residual carbonaceous material is in many applications of the present invention reduced by at least 40 % relative to the nitrogen content in the initial carbonaceous material such as a reduction of at least 50 %. Preferably the nitrogen content in the residual carbonaceous material is reduced by at least 60 % relative to the nitrogen content in the initial carbonaceous material such as at least 70 % relative to the nitrogen content in the initial carbonaceous material.

[0042] In many applications according to present invention, the concentration of nitrogen in the residual carbonaceous material is reduced to below 0,8 % by weight of the dry ash free carbonaceous material such as below 0,6 % by weight of the dry ash free carbonaceous material.

[0043] In a preferred embodiment the nitrogen content in the recovered bio-oil from the conversion step (b) is less than 0,5 % by weight such as less than 0,3 % by weight. Preferably the nitrogen content in the recovered bio-oil from the conversion step (b) is less than 0,2 % by weight such as less than 0,1 % by weight.

[0044] In some applications of the present invention the carbonaceous material has a high ash content that may lead to processing challenges in the conversion step (b) such as increased wear of equipment and pipes due to erosion and / or may result in increased fouling heat exchangers that may result in reduced process efficacy or a reduction in the onstream factor due to clogging and / or may result in result in a more difficult separation of the products from the conversion process that may lead to reduced process efficacy and product quality from conversion step (b).

[0045] Hence, a preferred embodiment according to the invention is where the ash content of the residual carbonaceous material is reduced by at least 60 % relative to the ash content of initial carbonaceous material prior to the conversion step (b) such as at least 70 % relative to the ash content of the residual carbonaceous material. In some advantageous embodiments the ash content of the residual carbonaceous material is reduced by at least 80 % relative to the nitrogen content in the initial carbonaceous material such as at least 90 % relative to the nitrogen content in the initial carbonaceous material.

[0046] In a number of embodiments, the carbonaceous material has a high concentration of phosphorous that may result in processing challenges such as fouling of heat exchangers and / or may result in a more difficult separation in the conversion step (b).

[0047] Hence, an advantageous embodiment of the present invention is where the phosphorous content of the residual carbonaceous material is reduced by at least 50 % relative to the phosphorous content of initial carbonaceous material such as a reduction of at least 60 % relative to the phosphorous content of initial carbonaceous material. In other advantageous embodiments the phosphorous content is reduced by at least 70 % such as at least 80 % relative to the phosphorous content of initial carbonaceous material.

[0048] By at least partly producing the alcohol from the carbon oxide containing process gas from the conversion process, the oil yield and the overall process efficiency is improved. By using low carbon intensity hydrogen, such as produced by electrolysis using low carbon intensity electricity such as produced from wind energy, solar energy, hydroper, geothermal energy and / or nuclear energy or a combination thereof, the carbon footprint and carbon intensity, respectively, of the produced oil are further reduced.

[0049] By producing the phenolics added to the process from a carbonaceous material in the form of a lignocellulosic material, the overall carbon footprint and carbon intensity of the produced oil is reduced as it is produced from a renewable source, i.e., a biogenic carbon source. Further by producing the phenolics in a separate conversion step the process conditions in the pre-conversion step can be optimized for production of phenolics and the conversion step is optimized for yield and quality of the low carbon intensity oil produced. Hereby the overall efficiency of the process may be improved.

[0050] Brief description of the drawings

[0051] The invention will be described in more detail in the following detailed description, with reference to embodiments shown in the drawings where:

[0052] FIG. 1 shows a schematic overview of a process according to the invention for converting a nitrogen and / or ash rich carbonaceous material into a first liquid product enriched in nitrogen and / or ash and a second bio-oil product comprising the step of fractionating the carbonaceous material into first liquid product and a residual carbonaceous material that is further converted in conversion step wherefrom bio-oil is recovered;

[0053] FIG. 2 shows a schematic overview of a another preferred embodiment of a process according to the invention, where the fractionation step further comprises an enzymatic treatment step.

[0054] FIG. 3 shows an overview of a process according to the present invention for converting the residual carbonaceous material into a bio-oil, a gaseous product, an alcohol / polyol / water phase and optionally a biochar product (solid product).

[0055] FIG. 4 shows a schematic overview of another preferred embodiment of a conversion process of the residual carbonaceous material according to the invention, where phenolics are at least partly provided by at least partly recycling the crude oil produced by the conversion process to the step of providing the feed mixture, and / or where alcohol / polyol recovered is at least partly recovered and recycled to the step of providing the feed mixture;

[0056] FIG. 5 shows a schematic drawing of a system of an embodiment of a process according to the invention, where phenolics are at least partly produced in a separate conversion step prior to the step of converting the residual carbonaceous material;

[0057] FIG 6 shows a schematic overview of a preferred embodiment according to the invention comprising a system for production of alcohol from the gas produced in the conversion process of the residual carbonaceous material, and at least partly recycling the alcohol produced to the conversion step of residual carbonaceous material;

[0058] FIG. 7 shows a schematic overview of an advantageous embodiment according to the invention comprising a system for producing methanol from the gas produced in the conversion process using hydrogen produced by electrolysis and at least partly recycling the methanol to the step of providing the feed mixture to the conversion process; and

[0059] FIG. 8 shows a schematic overview of another advantageous embodiment of a system for producing methanol from the gas produced in the conversion process of the residual carbonaceous material according to the invention further comprising using electricity produced by renewable electricity such as electricity produced from wind, solar and / or geothermal energy.

[0060] Description of a preferred embodiment

[0061] FIG. 1 shows a schematic overview of a preferred two stage process according to the present invention, where a nitrogen and / or ash rich carbonaceous material is first fractionated into a liquid product enriched in nitrogen and / or ash compounds and an intermediate residual carbonaceous material depleted in nitrogen and / or ash that is subsequent further processed in a conversion step, wherefrom a low carbon intensity bio crude oil is recovered from the converted residual carbonaceous material.

[0062] A carbonaceous material according to the present invention is generally a carbon containing material e.g. organic matter such as biomass and / or waste materials.

[0063] Some carbonaceous material(-s) according to the present invention have a high nitrogen and / or ash content. Though the nitrogen content of the oil produced is typically reduced compared to the nitrogen content in the unconverted carbonaceous material, a higher nitrogen content in the oil produced by the process will typically result, when carbonaceous materials having a high nitrogen content are processed according to the invention. A high nitrogen in the oil produced often limits its options for direct use e.g. in marine engines or combustion applications, and thus requires further down stream processing such as by hydroprocessing for reduction of the nitrogen content of the oil. It is further well known that nitrogen in crude oils is generally more difficult to remove in such hydroprocessing processes than oxygen, and requires more severe conditions. Still further the presence of nitrogen compounds in the liquefaction product often has a high emulsifying tendency, which may result in a more difficult separation of e.g. water and ash from the crude oil product. Hence, it is desirable to reduce the nitrogen content provided in the feed mixture to avoid such issues.

[0064] Some carbonaceous materials according to the present invention have or further have a high ash content that may lead to process disadvantages such as increased wear of equipment and pipes due to erosion and / or increased fouling of e.g. heat exchangers and / or a more difficult product separation and purification, which may lead to lower overall yields of products and / or reduced quality of the oil product and / or by-products.

[0065] The nitrogen rich and / or ash carbonaceous material may in many applications according to the invention first be subjected to a washing stage, where contaminants such as adhering dirt are removed. Often microbial contamination is also reduced in said washing stage.

[0066] Often the washing step may comprise a homogenization step such as a size reduction of the carbonaceous material such as one or more grinding, cutting, crushing, attriting and / or milling operations. Nonlimiting examples of suitable size reduction techniques include chippers, macerators, shredders, hammer mills, knife mills, shear mills, roller mills, disc mills, pins mills, ball mills, colloidal mills, stone mills and combinations thereof.

[0067] The size reduction increases the surface area of the carbonaceous material, facilitating the release of nitrogen compounds like proteins during the subsequent fractionation. Further the size reduction has an impact on the rheological properties of residual carbonaceous material fed to the conversion step.

[0068] In many embodiments according to the present invention the carbonaceous material is size reduced to a maximum particle size of 30 mm, 15 mm, 10 mm, 5 mm, 3 mm, 2 mm, 1 ,5 mm, 1 mm, 0,5 mm or 0,1 mm.

[0069] In a preferred embodiment according to the present invention the carbonaceous material is sized reduced to an average particle size of less than 2 mm, 1 ,5 mm, 1 ,25 mm, 1 ,0 mm, 0,75 mm, 0,5 mm, 0,25 mm, 0,1 mm or 0,05 mm. In some applications the washed and optionally size reduced material is further subjected to a mechanical dewatering and / or disintegrating operation such as a pressing and / or extruding operation thereby producing a liquid product enriched in proteins and an intermediate residual carbonaceous material product.

[0070] In many embodiments the fractionation step comprises contacting the carbonaceous material with a solvent at a temperature in the range 40 to 180 °C.

[0071] The solvent is added to help solubilize nitrogen compounds such as proteins and / or ash compounds and to homogenize or further homogenize the mixture for further extraction. The solvent selection depends on the specific carbonaceous material being processed and desired liquid product(-s) to be produced.

[0072] In a number of preferred applications the solvent in the step of fractionating comprises an alkaline solvent and the pH is maintained in the range 7 to 12 such as in the range 8 to 12 or in the range 8 to 10. The alkaline solvent may in many applications advantageously comprise sodium hydroxide and / or potassium hydroxide.

[0073] In other applications the solvent comprises an acidic solvent and pH during the fractionation may be maintained in the range 2 to 6 such as in the range 4 to 6. The acidic solvent may in many applications advantageously comprise sulphuric acid, acetic acid, hydrochloric acid, citric acid, oxalic acid or a combination thereof. In some preferred embodiments the acidic solvent may further comprise sodium acetate. In further preferred embodiments the solvent comprises or further comprises an organic solvent and / or a pH buffering solution such as a phosphate buffered saline solution or Tris-HCI buffering solution.

[0074] In some embodiments, the temperature is in the range 40 to 90 °C such as in the range 40 to 70 °C.

[0075] An advantage of the acid pre-treatment according to the present invention is that the content of both nitrogen and inorganics (ash) such as phosphorous are reduced.

[0076] Further preferred embodiments comprises a first fractionation using an alkaline solvent and a subsequent treating the separated residual carbonaceous material from the alkaline fractionation in a further fractionation step using an acidic solvent.

[0077] Another embodiment comprises a first fractionation step using an acidic solvent and a further fractionation step of the separated residual carbonaceous from the acidic fractionation using an alkaline solvent.

[0078] By performing such stepwise extraction it is obtained that certain nitrogen compounds such as certain proteins, peptides, and enzymes that may be insoluble or unstable under either alkaline or acidic conditions can be extracted and preserved or certain nitrogen compounds or certain proteins or peptides may be selectively extracted and isolated as a separate product, while maintaining the overall nitrogen and / or ash reduction targets of the residual carbonaceous material for the conversion step.

[0079] Depending on the specific carbonaceous material being treated and desired first product(-s), the nitrogen and / or ash enriched liquid(-s) produced during the fractionation of the carbonaceous material may be subjected to further concentration and purification steps such as filtration, centrifugation, precipitation and / or chromatographic techniques.

[0080] In some embodiments the liquid product(-s) from the fractionation step enriched in nitrogen and / or ash compounds may be subjected or further subjected to a microfiltration and / or ultrafiltration step to further concentrate and / or purify the product(-s).

[0081] In one embodiment the first liquid product(-s) comprising solubilized nitrogen compounds and / or inorganic (ash) compounds is used or further processed to a product for stimulating plant growth such as a nutrient product for plant growth.

[0082] In another embodiment the first liquid product(-s) comprises one or more protein enriched products that may be used or further processed to a product for use in a feed, food, food ingredients, nutritional or pharmaceutical application.

[0083] Depending on the specific carbonaceous material being processed, the fractionation step according to the present invention may be designed to reduce either the nitrogen content or the ash content or both the nitrogen and the ash content of the residual carbonaceous material being fed to the conversion step of the residual carbonaceous material.

[0084] The concentration of nitrogen in the residual carbonaceous material may in many applications be reduced by at least 40 % by weight relative to the nitrogen content in the initial carbonaceous material such as at least 50 % by weight relative to the nitrogen content in the initial carbonaceous material. Preferably the nitrogen content in the residual carbonaceous material is reduced with at least 60 % relative to the nitrogen content in the initial carbonaceous material such as at least 70 % by weight relative to the nitrogen content in the initial carbonaceous material.

[0085] In one embodiment the nitrogen content of the residual carbonaceous material fed to the conversion step is reduced to below 0,8 % of the weight of the dry ash free residual carbonaceous material such as reduced to nitrogen content to below 0,6 % by weight of the dry ash free residual carbonaceous material. In other preferred embodiments the nitrogen content of the carbonaceous material provided to the feed mixture is controlled to below 0,4 % by weight, below 0,3 % by weight, and below 0,2 % of the weight of the dry ash free residual carbonaceous material.

[0086] In a preferred embodiment of the invention the ash content of the residual carbonaceous material provided to the conversion step is controlled to below 10 % by weight such as below 8 % by weight, 6 % by weight, 4 % by weight.

[0087] In several applications of the present invention, the carbonaceous material has a high concentration of phosphorous that may result in processing challenges such as fouling of heat exchangers and / or may result in a more difficult product separation in the conversion step.

[0088] Hence, an advantageous embodiment of the invention is where the phosphorous content of the residual carbonaceous material to the conversion step is reduced by at least 50 % by weight such as a reduction of the phosphorous content of the residual carbonaceous material of at least 60 % by weight. In other advantageous embodiments the phosphorous content is reduced by at least 70 % such as at least 80 % by weight.

[0089] By performing a fractionation of the carbonaceous material according to the present invention several benefits are obtained such as an overall more efficient utilization of the carbonaceous material resulting in a more sustain- able, circular and efficient process allowing for production of valuable nitrogen and or ash rich by-product(-s) and results in a residual carbonaceous material depleted in nitrogen and / or ash rich compounds that are more effectively can be converted into bio-oil in the conversion step, e.g., with higher bio-oil yield, lower carbon intensity of the crude oil, lower nitrogen content of the low carbon intensity crude oil, higher onstream factor, more efficient separation. A further benefit may be that the residual carbonaceous material has improved rheological properties and is easier to pump at high dry matter contents.

[0090] FIG. 2 shows a schematic overview of another preferred embodiment of a process according to the invention, where the residual carbonaceous material produced in the fractionation step described above under FIG 1 is further subjected to an enzymatic treatment step prior to further reducing the nitrogen and / or ash content of the residual carbonaceous material being fed to the conversion step.

[0091] The enzyme treatment may according to the present invention be performed at relatively mild conditions such as at a temperature in the range 40 - 70 °C such as 50 °C.

[0092] Suitable enzymes for said enzymatic treatment include acid proteases.

[0093] FIG. 3 shows a preferred embodiment of a production process for conversion of the residual carbonaceous material to bio-oil in the conversion step (b).

[0094] The residual carbonaceous material depleted in nitrogen and / or ash compound is typically pressurized to a conversion temperature in the range 10 bar to 220 bar and heated to a conversion temperature of 280 to 500 °C, and the converted feed mixture is separated into phases containing mainly a biooil, a gas, a water and a solid / biochar product. In an advantageous embodiment, the conversion step (b) is performed in the presence of phenolics and / or one or more alcohols and / or polyols as indicated by the dotted arrows in the providing feed mixture step.

[0095] The conversion of residual carbonaceous material in the presence of phenolics and / or alcohol according to the present invention improves the yield and quality of the bio-oil by applying one or more solvents that act as efficient hydrogen donors for the conversion of the residual carbonaceous product to bio-oil, provide increased solubility of oily products, favor deoxygenation and hydrogenolysis reactions, and stabilize the reactive intermediate products e.g. by forming acetals with carbonyl groups such as ketones and aldehydes, and esters with carboxylic acids. Thereby conversion of the carbonaceous material in the presence of the solvents according to the present invention retards repolymerization to high molecular weight products often called solid residues or biochar and may lead to lower yields and quality of the bio-oil.

[0096] The pressure during the conversion of the feed mixture is often at least 20 bar such as at least 40 bar; preferably the pressure during the conversion of the feed mixture is at least 60 bar such as at least 70 bar; more preferably the pressure during the conversion of the feed mixture is at least 80 bar such as at least 90 bar; even more preferably the pressure during the conversion of the feed mixture is at least 100 bar such as at least 110 bar.

[0097] In many applications the pressure during the conversion of the feed mixture is maintained below 250 bar such as below 220 bar. Often the pressure during the conversion of the feed mixture is maintained below 180 bars such as below 160 bar. In some embodiments the pressure during the conversion of the feed mixture is below 150 bars such as below 140 bar. In further embodiments the pressure during the conversion of the feed mixture is maintained below 130 bar such as below 120 bar. In many embodiments the pressure during the conversion process is maintained in the range from 20 bar below to 20 bar above the critical pressure of the fluid mixture.

[0098] Advantageously the pressure during the conversion of the feed mixture is maintained above the boiling point pressure of the fluid mixture so as to maintain the fluid mixture in a liquid or supercritical state.

[0099] The conversion of the feed mixture is often performed at a temperature of at least 300 °C such as a temperature of at least 310 °C. In some embodiments the conversion of the feed mixture is performed at a temperature of at least 320 °C such as at a temperature of at least 330 °C. In other embodiments the conversion of the feed mixture is performed at a temperature of at least 340 °C such as a temperature of at least 350 °C. In further embodiments the conversion of the feed mixture is performed at a temperature of at least 360 °C such as a temperature of at least 370 °C.

[0100] Preferred embodiments include converting the feed mixture at a temperature of less than 450 °C such as a temperature of less than 410 °C. Often the conversion of the feed mixture is performed at a temperature of less than 390 °C such as at a temperature of less than 380 °C. In some embodiments the conversion of the feed mixture is performed at a temperature of less than 360 °C such as at a temperature of less than 350 °C.

[0101] In a preferred embodiment, the conversion of the residual carbonaceous material is performed in the presence of phenolics in a concentration of at least 5 % by weight preferably at least 7,5 % by weight. Preferred embodiments of the invention include embodiments, where the concentration of phenolics in the feed mixture is at least 7,5 % by weight, at least 10 % by weight, at least 12,5 % by weight, at least 15 % by weight, at least 15 % by weight or at least 20 % by weight.

[0102] The ratio of the weight of phenolics to the dry ash free weight of the residual carbonaceous material is in many embodiments at least 0,2 such as at least 0,3; Preferred embodiments include embodiments where the ratio of the weight of phenolics to the dry ash free weight of the residual carbonaceous material is at least 0,4, at least 0,5, at least 0,6 or at least 0,7 such as at least 0,8. In further preferred embodiments the ratio of weight of phenolics to the dry ash free weight of the residual carbonaceous material is at least 0,9, at least 1 ,0 or at least 1 ,5.

[0103] In an advantageous embodiment the phenolics added comprises phenol in a concentration of at least 2 % by weight such as in a concentration of at least 4 % by weight. In further advantageous embodiments the feed mixture comprises phenol in a concentration of at least 6 % by weight, at 8 % by weight, at least 10 % by weight, at least 12 % by weight, at least 15 % by weight or at least 18 % by weight, such as at least 20 % by weight.

[0104] In an advantageous embodiment, the phenolics in the conversion step of residual are at least partly produced by the process.

[0105] In one embodiment, the phenolics in the feed mixture are at least partly provided by recycling at least part of the bio-oil produced by the process.

[0106] In an advantageous embodiment, the phenolics are produced by conversion of a lignocellulosic material in the presence of phenolics and one or more alcohols and an acid at conversion temperatures in the range 160 to 260 °C and conversion pressures in the range 5 to 90 bar. Advantageous embodiments of the invention include embodiments where the conversion of the residual carbonaceous material is performed in the presence of one or more alcohols and / or polyols in a concentration of at least 5 % by weight. In one embodiment, the concentration of the one or more alcohols and / or is at least 10 % by weight such as at least 15 % by weight. In other preferred embodiments the concentration of the one or more alcohols and / or polyols is at least 20 % by weight, at least 25 % by weight, at least 30 % by weight, at least 35 % by weight or at least 40 % by weight.

[0107] In a preferred embodiment the one or more alcohols and / or polyols according to the invention comprises methanol, ethanol, propanol, isopropanol, butanol, isobutanol, pentanol, glycerol, ethylene glycol, polyethylene glycol, propylene glycol, catechol’s or a combination thereof.

[0108] In a preferred embodiment the process according to the invention is continuous.

[0109] In an aspect of the invention the feed mixture comprises one or more acids selected from formic acid, acetic acid, citric acid, sulphuric acid, and combinations thereof.

[0110] In a preferred embodiment the one or more acids are at least partly produced by the process. The acid concentration may according to embodiments of the invention be in the range from about 3 % by weight to about 10 % by weight.

[0111] The bio-oil product produced by a method of the invention generally has a low carbon footprint such as a carbon intensity of less than 20 g CO2 / MJ bio-oil produced such as a carbon intensity below 15 g CO2 / MJ. In some embodiments the carbon intensity is below 12,5 CO2 / MJ such as below 10 g CO2 / MJ. The bio-oil product produced according to a method of the invention generally has a low acid number. In a preferred embodiment the acid number of the low carbon intensity oil is below 10 mg KOH / g such as below 7 mg / g, preferably less 5 mg KOH / g such as less than 3 mg KOH / g.

[0112] The low carbon intensity oil produced according to the present invention may have higher heating value of at least 25 MJ / kg such as at least 30 MJ / kg, preferably the oil has a higher heating value of at least 32 MJ / kg such as at least 34 MJ / kg; more preferably the bio-oil has a higher heating value of at least 34 MJ / kg such as at least 36 MJ / kg; even more preferably the oil product has a higher heating value of at least 38 MJ / kg such as a higher heating value of at least 40 MJ / kg.

[0113] FIG. 4 shows a schematic overview of another preferred embodiment of a process according to the invention, where phenolics are at least partly provided by at recycling at least part of the crude oil produced by the process to the step of providing the feed mixture such as recycling of a phenolics rich fraction, and / or where alcohol is at least partly recovered and recycled to the step of providing the feed mixture in the conversion step (b).

[0114] The converted feed mixture is cooled and depressurized to desired separations conditions and separated into an oil phase, a gas phase, an alcohol / polyol / water phase and a solid phase.

[0115] In a preferred embodiment, the separation system comprises a gravimetric separation at pressures of 30 to 120 bar and temperatures from 130 to 400 °C. such as at pressure in the range 30 to 60 bars and temperatures of 130 to 260 °C.

[0116] In an advantageous embodiment the separated oil phase is at least partly recycled to the step of providing the feed mixture. In another advantageous embodiment alcohol is at least partly recovered from the converted feed mixture after separation and recycled to the step of providing the feed mixture.

[0117] In a preferred embodiment the recovery of alcohol comprises one or more flashing steps.

[0118] In an advantageous embodiment the recovery of alcohol comprises separating alcohol from water by a distillation technique.

[0119] In another advantageous embodiment the recovery of alcohol comprises separating alcohol from water using one or more membrane techniques.

[0120] FIG. 5 shows a schematic drawing of a system of an embodiment of a conversion process according to the invention, where renewable phenolics are at least partly produced from one or more carbonaceous material(-s) in a separate pre-conversion step prior to the step of providing the feed mixture to the conversion step (b) of process.

[0121] One or more carbonaceous material(-s) is / are at least partly converted to phenolics in a pre-conversion zone (1) in the presence of phenolics and one or more alcohol and / or polyol to form an oil rich in phenolics, a gas phase, a water phase and / or a solid phase product. After separation from other product phases produced in the pre-conversion zone (1 ), the phenolic rich oil phase is according to an advantageous embodiment at least partly introduced to the step of providing the feed mixture in the conversion step of the process as described in further details under FIG. 3 and FIG. 4 above.

[0122] The temperature for conversion of the one or more carbonaceous materials in the pre-conversion zone (1 ) may according to a preferred embodiment of the present invention be in the range from 150 °C to 240 °C such as in the range 160 °C to 225 °C. Preferably, the temperature for conversion of the one or more carbonaceous materials in the pre-conversion zone (1 ) is in the range 175 °C to 210 °C such as in the range 180 °C to 200 °C.

[0123] The pressure for conversion of the one or more carbonaceous materials in the pre-conversion zone (1 ) is typically in the range 5 to 90 bar such as in the range 8 to 80 bar. Preferably the pressure for conversion of the one or more carbonaceous materials in the pre-conversion zone (1 ) is in the range 10 to 70 bar such as in the range 15 to 60 bar. More preferably the pressure for conversion of the one or more carbonaceous materials in the pre-conversion zone (1) is in the range 15 to 50 bar such as in the range 20 to 40 bar.

[0124] In a preferred embodiment the concentration of phenolics in the feed mixture added to the pre-conversion zone (1) is at least 2 % by weight of the feed mixture. In other embodiments the concentration of phenolics may be at least 3 % by weight of the feed mixture, at least 5 % by weight of the feed mixture, at least 8 % by weight of the feed mixture, at least 10 %% by weight of the feed mixture, at least 12 % by weight of the feed mixture, at least 15 % by weight of the feed mixture such as at least 20 % by weight of the feed mixture to the preconversion zone (1 ).

[0125] Advantageously, the concentration of phenol in the feed mixture fed in the preconversion zone (1 ) is at least 1 % by weight of the feed mixture. In other embodiments the concentration of phenol may be at least 2 % by weight of the feed mixture, at least 3 % by weight of the feed mixture, at least 5 % by weight of the feed mixture, at least 8 % by weight of the feed mixture, at least 10 % by weight of the feed mixture, at least 12 % by weight of the feed mixture, at least 15 % by weight of the feed mixture such as at least 20 % by weight of the feed mixture to the pre-conversion zone (1 ). Advantageously, at least part of the phenolics added to the feed mixture to the pre-conversion zone (1 ) is comprised by recycling at least part of the oil product produced in the pre-conversion zone (1 ) as shown in Fig. 3.

[0126] The concentration of alcohols and / or polyols in the feed mixture to the preconversion zone (1) may in a preferred embodiment be at least 5 % by weight of the feed mixture such as at least 10 % by weight of the feed mixture; preferably the concentration of alcohols and / or polyols in the feed mixture to the pre-conversion zone (1 ) is at least 15 % by weight of the feed mixture, 20 % by weight of the feed mixture, 30 % by weight of the feed mixture, 40 % by weight of the feed mixture, 50 % by weight of the feed mixture, 60 % by weight of the feed mixture.

[0127] Advantageously, the one or more alcohols and / or polyols added to the feed mixture to the pre-conversion zone (1 ) has a renewable origin e.g. is produced from biogenic resources and / or renewable electricity, whereby the carbon footprint of the products from the process is reduced.

[0128] An advantageous embodiment is where the one or more alcohols and / or polyols added to the feed mixture to the pre-conversion zone (1 ) comprises methanol produced from the carbon oxide rich process gas produced by the conversion process in zone 1 and 2.

[0129] In some preferred embodiments, the conversion of the one or more carbonaceous materials in the pre-conversion zone (1 ) is performed in the presence of one or more acid catalysts.

[0130] In an advantageous embodiment, the acid catalyst added to the feed mixture added to the pre-conversion zone comprises sulphuric acid in a concentration of 1 to 5 % by weight of the feed mixture such as 2 to 4 % by weight of the feed mixture added to the pre-conversion zone (1 ). The residence time in the pre-conversion zone (1 ) may in many applications of the present invention be in the range from 1 minutes to 180 minutes such as in the range from 2 minutes to 120 minutes. Preferably the residence time in the pre-conversion zone (1) is in range from 5 minutes to 60 minutes such as in the range from 10 minutes to 30 minutes.

[0131] The one or more carbonaceous material(-s) provided to the pre-conversion zone (1) is typically selected so that the carbonaceous material contains lignin such as lignocellulosic materials.

[0132] In a preferred embodiment of the invention, the lignin content of the carbonaceous material(-s) added to the pre-conversion zone (1 ) of the present invention is / are at least 10 % of the dry ash free weight of the carbonaceous material(-s) such as at least 15 % of the dry ash free weight. In some applications the lignin content of the carbonaceous material(-s) added to the pre-conversion zone (1) of the present invention is / are at least 20 % of the dry ash free weight of the carbonaceous material(-s) such as at least 25 % of the dry ash free weight.

[0133] The phenolic rich oil phase from the pre-conversion zone (1 ) is at least partly added to the step of providing the feed mixture in the conversion zone (2), where the carbonaceous material(-s) is / are further converted as described above under FIG. 3 and FIG. 4.

[0134] Hereby the phenolics used in the process are produced from a renewable source (biogenic carbon) in the process, whereby the overall carbon footprint is reduced. Further, by producing the phenolics in a separate conversion step it is obtained that process conditions in the pre-conversion step can be optimized for production of phenolics and the can conversion step be optimized for yield and quality of the oil produced. Hereby the overall efficacy of the process and carbon intensity of the oil product are improved.

[0135] FIG. 6 shows a schematic overview of a preferred embodiment according to the invention comprising a system for producing alcohol(-s) from the gas produced in the conversion process of the residual carbonaceous material, and at least partly recycling the alcohol produced to the step of providing the feed mixture of the conversion process.

[0136] The residual carbonaceous materials from the fractionation process are subjected to a conversion process in the presence of one or more alcohols, thereby resulting in a converted residual carbonaceous material comprising oil, process gas, and a water phase and optionally solid / biochar phase as illustrated in FIG. 6.

[0137] The conversion process of the residual carbonaceous material is advantageously performed under pressure such as at a pressure of at least 10 bar, 20 bar, 30 bar, 40 bar, 50 bar, 60 bar, 80 bar or 100 bar.

[0138] In many embodiments the pressure during the conversion of the residual carbonaceous material is below 400 bar, 350 bar, 300 bar, 250 bar, 200 bar, 180 bar or 160 bar.

[0139] The temperature during the conversion process of the residual carbonaceous material is typically at least 280 °C such as at least 300 °C. Preferably, the temperature during the conversion process of the residual carbonaceous material is at least 325 °C such as at least 350 °C. More preferably the temperature during the conversion process of the residual carbonaceous material is at least 370 °C such as at least 385 °C. The process gas produced by conversion process of the residual carbonaceous material(-s) comprises carbon oxides such as carbon dioxide and carbon mono oxide as the main compounds. The amount of process gas and the composition of the gas depend on the specific operating conditions, and residual carbonaceous material(-s) being converted, but often further comprises Ci to C4 hydrocarbons, hydrogen, and condensable like water and alcohol.

[0140] As shown in the FIG. 6, the process gas from the conversion process of the residual carbonaceous material is subjected to an a methanol synthesis step, where the process gas is reacted with hydrogen to produce one or more methanol with water as a by-product.

[0141] Typically, the alcohol synthesis step according to the present invention involves at least one catalytic reaction step for reacting the carbon oxides in the process gas with hydrogen in the presence of one or more metal catalyst(- s).

[0142] The catalytic reaction step is often performed at pressures in the range 30 to 150 bar, and temperatures in the range 200 to 450 °C such as pressures of 50 to 100 bar and temperatures in the range 200 to 300 °C.

[0143] Suitable metal catalysts according to the invention include copper zinc oxide catalysts, copper zinc chromium catalysts, copper mixed oxides catalysts, iron oxide catalysts on an alumina, zirconia carrier or zeolite carrier material. Other metal promotors and modifications may be added to the catalyst structure for activity and selectivity enhancement.

[0144] In one embodiment, the catalytic reaction step is arranged as a fixed-bed reaction system comprising one or more fixed beds comprising the metal catalyst(-s). Another configuration of the catalytic reaction step according to the present invention is as a fluidized-bed reactor system containing the metal catalyst(-s) fluidized by the gas feedstock.

[0145] The conversion per pass in the catalytic reaction step is often relatively low e.g., in the range 10-40% such as in the range 20 to 30 %. Hence, an advantageous embodiment is where the unreacted carbon oxides and hydrogen are at least partly recycled back into the catalytic reactor after intermediate separation of produced alcohol and water as shown in FIG. 6. Hereby the overall conversion efficiency is increased.

[0146] As also shown in the FIG. 6 the alcohol produced from the process gas is at least partly recycled to the conversion process of the residual carbonaceous material. Hereby, the overall bio-oil yield and efficiency of the conversion process of the carbonaceous material and the resulting carbon footprint of the bio-oil produced are reduced.

[0147] FIG. 7 shows a schematic overview of an embodiment of a system similar to FIG. 6, where the alcohol(-s) produced from the process gas is methanol, and where the hydrogen added to the methanol synthesis is produced by electrolysis. As seen from the figure oxygen is produced as a by-product in the electrolysis.

[0148] As illustrated the methanol and water produced in the methanol synthesis may be separated from unreacted gases by flashing and may be at least partly recycled and mixed with the incoming process gas to the methanol to achieve a higher overall conversion. The liquid fraction from the flash separation (3) may be further separated (4) into a methanol stream and water stream by conventional means such as by distillation. As illustrated the separated water may at least partly be recycled to the electrolysis unit (2), and the methanol produced may be at least partly recycled to the conversion process thereby increasing the overall process efficiency, and reducing the chemical consumption as well as the carbon footprint of the oil produced from the residual carbonaceous material.

[0149] FIG. 8 shows a schematic overview of an advantageous embodiment of a system for producing methanol from the gas produced in the conversion process of the residual carbonaceous material according to the invention further comprising using electricity produced renewable sources such as wind, solar and / or geothermal energy in the electrolysis unit (2), whereby the carbon footprint of the oil produced from the residual carbonaceous material is further reduced.

[0150] Also shown in FIG. 8 is a syngas preparation unit (1) prior to the methanol synthesis step (3). The syngas preparation unit (1) may according to the invention include means for adjusting the molar Fb / CO-ratio to a molar H2 / CO- ratio in the range 1 ,8 to 2,2 as well as means for removing impurities such as sulphur and nitrogen compounds, and other trace elements, to prevent poisoning of the catalyst used in the methanol synthesis reaction.

[0151] The adjustment of the molar Fb / CO-ratio may be performed through a variety of processes such as thermochemical, electrochemical, or biological conversion processes and combinations thereof.

[0152] In one embodiment, the means for adjusting the Fb / CO-ratio include adding hydrogen preferably electrolytic hydrogen at least partly produced by low carbon intensity electricity such as produced by wind power, solar power, hydropower, geothermal power, nuclear power or combinations thereof to the syngas preparation unit. In another embodiment, the means for adjusting the molar Fb / CO-ratio include performing a reverse water gas shift reaction (RWGS), where CO2 and H2 are reacted to produce CO and water vapor (H2O). The means for adjusting the H2 / CO-ratio by RWGS reaction may be performed by conventional means such as by reaction in a catalytic reactor. Suitable catalysts for the RWGS reaction include supported bimetallic catalysts combining two or more different transition metals such as Fe, Co, Ni, Cr, Zn, Co, Cu, Ce on a high surface area porous supporting material such as alumina, silica, zeolites or carbon supports.

[0153] The reaction temperature depends on the specific catalyst and process configuration.

[0154] One embodiment of the present invention comprises a syngas preparation unit where a reverse water gas shift reaction of the process gas operating at temperatures in the range 300 to 500°C such as 300 to 400 °C and pressures in the range 10-50 bar such as 30 to 40 bar.

[0155] Another preferred embodiment is where the syngas preparation unit comprises an electrochemical reverse water gas shift (eRWGS) process where carbon oxide (CO, CO2) containing process gas from the conversion process of the residual carbonaceous material is converted to syngas in an electrochemical cell.

[0156] The electrochemical cell may comprise one or more catalyst(-s) to promote the reverse gas reaction. Often the operating temperature of the electrochemical cell is at least 400 °C, 500°C, 600 °C, 700 °C, 800 °C or 900 °C and even at least 1000 °C. In a preferred embodiment heat from the syngas preparation and / or methanol is transferred to the conversion process of the residual carbonaceous material.

[0157] DEFINITIONS

[0158] Bio-oil

[0159] The term oil in the present context is used to describe hydrocarbons and oxygenated hydrocarbons produced from a biogenic carbonaceous material such as biomass and residue materials. Bio-oil according to the present invention generally has a substantial decarbonization effect due to avoided greenhouse gas emissions. The decarbonisation effect may be due avoidance of emissions related to alternative use of the carbonaceous feedstock, the use of renewable carbonaceous materials such as biomass and / or other renewable raw materials to produce the oil e.g. resulting in an oil product having a low carbon intensity and / or having a high content of biogenic carbon content and thus resulting in a significant / substantial decarbonization when used to substitute fossil oils and / or chemicals.

[0160] Low carbon intensity oil

[0161] The term low carbon intensity oil in the present context is used to describe hydrocarbons and oxygenated hydrocarbons. The low carbon intensity oil according to the present invention generally have a significant / substantial decarbonization effect due to avoided greenhouse gas emissions.The decarbonisation effect may be due avoidance of emissions related to alternative use of the carbonaceous feedstock, the use of renewable carbonaceous materials such as biomass and / or other renewable raw materials to produce the oil e.g. resulting in an oil product having a low carbon intensity and / or having a high content of biogenic carbon content and thus resulting in a significant / substantial decarbonization when used to substitute fossil oils and / or chemicals. Phenolics

[0162] Phenolics in the present context are used to describe chemical compounds consisting of one or more hydroxyl groups (-OH) bonded directly to an aromatic hydrocarbon group.

[0163] Alcohols

[0164] Alcohols are molecules containing the hydroxy functional group (-OH) that is bonded to the carbon atom of an alkyl or substituted alkyl.

[0165] Polyol

[0166] A polyol in the current context is an organic compound containing multiple hydroxyl groups.

[0167] Nitrogen rich carbonaceous material

[0168] A nitrogen rich carbonaceous material in the current context is a carbonaceous material having a nitrogen content of at least 0,8 % by weight of the dry ash free carbonaceous material.

[0169] Ash rich carbonaceous material

[0170] An ash rich carbonaceous material in the current context is a carbonaceous material having an ash content of at least 3 % by the dry weight of the carbonaceous material.

Claims

CLAIMS1 . Method of processing nitrogen and / or ash rich carbonaceous material(-s) into a first liquid product enriched in nitrogen and / or ash compounds and a second bio-oil product comprising the steps of a. Fractionating the carbonaceous material into a liquid product enriched in nitrogen and / or ash compounds and a residual carbonaceous material depleted in nitrogen and / or ash b. Converting the residual carbonaceous material in a thermochemical conversion process at pressures in the range 10 to 400 bar and temperatures in the range 280 to 500 °C and recovering bio-oil from the converted residual carbonaceous material.

2. Method according to claim 1 , where the nitrogen content of the nitrogen and / or ash rich carbonaceous material(-s) is at least 0,8 % by weight.

3. Method according to any of the claims 1 or 2, where the ash content of the nitrogen and / or ash rich carbonaceous material is at least 4 % by weight.

4. Method according to any of the claims 1 to 3, where the step of fractionating the carbonaceous material (step a) comprises contacting the carbonaceous material with a solvent at a temperature of 40 to 180 °C;5. Method according to any of the claims 1 to 4, where the solvent in the step of fractionating the carbonaceous material comprises an alkaline solvent and the pH during the fractionation (step a) is maintained in the range 7 to 12.

6. Method according to claim 5, where the solvent comprises sodium hydroxide and / or potassium hydroxide.

7. Method according to any of the claims 1 to 4, where the solvent comprises an acidic solvent and pH during the fractionation is maintained in the range 2 to 6.

8. Method according to claim 7, where the acidic solvent comprises sulphuric acid, acetic acid, hydrochloric acid, citric acid, oxalic acid or a combination thereof.

9. Method according to any of the claim 7 or 8, where the acidic solvent further comprises sodium acetate.

10. Method according to any of the claims 7 to 9, where the pH during the fractionation is maintained in the range 4 to 6.

11. Method according to any of the preceding claims, where the temperature is in the range 40 to 90 °C.

12. Method according to any of the preceding claims, where the solvent comprises or further comprises an organic solvent and / or a pH buffering solution.

13. Method according to any of the preceding claims, where the fractionation step (a) comprises or further comprises an enzymatic treatment of the carbonaceous material or the residual carbonaceous material from the first fractionation to further reduce the nitrogen and / or ash content.

14. Method according to claim 13, where the enzymes used in the enzymatic treatment comprises proteases.

15. Method according to claim 13 or 14, where the temperature of enzymatic treatment is in the range 40 to 70 °C.

16. Method according to any of the preceding claims, where the fractionation step (a) comprises a first fractionation using an alkaline solvent followed second fractionation step where the residual carbonaceous material from the alkaline fractionation step Is treated using an acidic solvent.

17. Method according to any of the preceding claims where the fractionation step (a) comprises a first fractionation using an acidic solvent followed second fractionation step where the residual carbonaceous material from the acidic fractionation step is treated using an alkaline solvent.

18. Method according to any of the preceding claims, where the first liquid product(-s) enriched in nitrogen and / or ash compounds is further subjected to one or more steps comprising a filtration, a centrifugation, a precipitation and / or a chromatographic technique or a combination thereof.

19. Method according claim 18, where the first product comprises one or more protein or peptide enriched products.

20. Method according to any of the preceding claims, where the first product comprises a nutrition product for plant growth or a precursor thereof.

21. Method according to any of the preceding claims, where the conversion of the residual carbonaceous material in the conversion step (b) is performed in the presence of phenolics in a concentration of at least 3 % by weight.

22. Method according to any of the preceding claims, where the conversion of the residual carbonaceous material in the conversion step (b) is performedin the presence of one or more alcohols and / or polyols in a concentration of at least 5 % by weight.

23. Method according to any of the claims 21 or 22, where the phenolics is provided by recycling at least part of the oil produced by the process.

24. Method according to claim 23, where the phenolics are produced by conversion of a lignocellulosic material in the presence of phenolics and one or more alcohols and an acid at conversion temperatures in the range 160 to 260 °C and conversion pressures in the range 5 to 90 bar.

25. Method according to any of the preceding claims, where the one or more alcohols and / or polyols is at least partly produced from carbon oxide rich gas recovered from the converted residual carbonaceous material.

26. Method according to any of the preceding claims, where the concentration of nitrogen in the residual carbonaceous material is reduced by at least 40 % relative to the nitrogen content in the initial carbonaceous material.

27. Method according to any of the preceding claims, where the concentration of nitrogen in the residual carbonaceous material is reduced to below 0,5 % by weight of the dry ash free carbonaceous material.

28. Method according to any of the claims preceding claims, where the phosphorous content of the residual carbonaceous material is reduced by at least 50 % relative to the phosphorous content of initial carbonaceous material.

29. Method according to any of the preceding claims, where the ash content of the residual carbonaceous material is reduced by at least 60 % relative to the ash content of initial carbonaceous material.

30. Method according to any of the preceding claims, where the nitrogen content in the recovered bio-oil from the process is less than 0,5 % by weight.

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