Abstract: The present invention relates to separation of lignin from an aqueous slurry containing lignocellulosic biomass material comprising providing the aqueous slurry having an initial pH level to at least one precipitation phase for precipitating lignin, performing said precipitation phase during a reaction time including adding at least one acidifier, wherein a decrease in the pH value of the aqueous slurry to a lower ph level is created, separating the lignin in a first separation phase, performing an acidification phase including, performing a re-slurry step including mixing lignin from the first separation phase with an acidifier to form an acidic slurry, establishing a reaction temperature in a range of 65-95 degrees Celsius. and performing a retention step including maintaining the acidic slurry at the reaction temperature for a reaction time period of 30-60 minutes, and separating the treated lignin content from the acidic slurry in a second separation phase.

Abstract: The invention relates to separation of lignin from an aqueous slurry containing lignocellulosic biomass material, such as black liquor, comprising the steps of providing an aqueous slurry having an initial pH level to a first precipitation phase, where the first precipitation phase is performed during a first time duration including adding a first acidifier. Thereby, a decrease in the pH value of the aqueous slurry from the initial pH level to a first pH level above 11 is created. Thereafter, processed aqueous slurry is fed from the first precipitation phase to a second precipitation phase. The second precipitation phase is performed during a second time duration. The second precipitation phase includes adding of a second acidifier, wherein a decrease in the first pH value from said first pH level to a second pH level above 9 is created.

Abstract: The present invention relates to a method of producing lignin with reduced amount of guaiacoland etylguaiacol in order to reduce the content of odorous substances by subjecting the ligninto a heating processing order to remove guaiacol.

Abstract: The present invention relates to a method of producing lignin with reduced amount of odorous substances comprising the step of: providing a solid phase lignin containing starting material to be contacted with a water solution comprising carboxylic acid; dissolving the guaiacol and etylguaiacol content from the lignin into the water solution, and draining off the water solution with its content of guaiacol or etylguaiacol; obtaining a lignin material with a reduced content of guaiacol or etylguaiacol. The invention also relates to a lignin product with reduced odour obtained and/or obtainable by the method obtained lignin as a component in polymer blends, an additive or filler in building materials, as binding agent in adhesives, and/or for the production of a carbon fibre, especially in indoor applications.

Abstract: Lignin-rich starting material is suspended in a first medium, which is acidic and aqueous, to form a aqueous acidic suspension, which is heated and allowed to form two continuous phases, a thermoplastic lignin phase and an aqueous phase. The thermoplastic lignin phase is separated from the aqueous phase and passed through a shape giving process into a second medium which is at a temperature lower than that of the thermoplastic lignin phase and in which the thermoplastic lignin phase is essentially insoluble. Solid lignin formed in the second medium is recovered.

Abstract: Lignin-rich starting material is suspended in a first medium, which is acidic and aqueous, to form a aqueous acidic suspension, which is heated and allowed to form two continuous phases, a thermoplastic lignin phase and an aqueous phase. The thermoplastic lignin phase is separated from the aqueous phase and passed through a shape giving process into a second medium which is at a temperature lower than that of the thermoplastic lignin phase and in which the thermoplastic lignin phase is essentially insoluble. Solid lignin formed in the second medium is recovered.

Abstract: The method is for separation of lignin from original black liquor (BLIN) having a first precipitation phase (PR1/PR2) for precipitation of lignin by a first acidification using acidifier, CO2, at alkaline conditions, then separating a lignin cake with subsequent suspension of the lignin cake in a strong acid to leach our metals from the lignin followed by dewatering and obtaining a clean lignin product LP. The acidic liquid phase (FL1) subjected to a sulphur removal process wherein a calcium containing compound is added to the acidic liquid phase, whereby sulphur in the acidic liquid phase is reacting with the calcium compound forming solid gypsum which could be separated and bled off from the process. The remaining acidic liquid could then be returned to the recovery process without negatively affecting the sulphur balance of the mill.

Abstract: The method is for separation of lignin from original black liquor (BLIN) having the following phases in sequence; a first precipitation phase (PR1) for precipitation of lignin by a first acidification of the original black liquor by adding a first acid or mixture of acids (G1a); followed by a second precipitation phase (PR2) for precipitation of lignin by a further acidification of the original black liquor by adding a second acid or mixture of acids (G1b). The first phase is implemented to lower the pH while avoiding any larger amount of precipitation, i.e. less than 2-5%, while the second phase is implemented in order to obtain the larger part of the precipitation. In total is 40-70% of the total lignin content of the original black liquor precipitated while the residual black liquor after precipitation is still strongly alkaline.

Abstract: The method is for separation of lignin from original black liquor (BLIN) and has the following phases in sequence. A first precipitation phase (PR1) for precipitation of lignin by a first acidification of the original black liquor by adding a first acid or mixture of acids (G1a) followed by a first storage phase wherein precipitated lignin particles are allowed to increase in size, followed by a second precipitation phase (PR2) for precipitation of lignin by a further acidification of the original black liquor by adding a second acid or mixture of acids (G1b). By retaining the acidified black liquor for at least 25 minutes in the storage phase are the precipitated lignin particles allowed to grow in size and the filterability is improved considerably.

Abstract: The method is for separation of lignin from original black liquor. Lignin is precipitated in a first acidification stage followed by dewatering a first lignin suspension while forming a first filter cake. The first lignin filter cake is suspended in a second acidification stage whereupon a second lignin suspension is obtained. The second lignin suspension is dewatered to form a second filter cake. The second filter cake is washed and the washed second lignin cake is dewatered to obtain a lignin product. Waste gases from the second acidification stage is recirculated back to the first acidification stage and mixed with the original black liquor.

Abstract: The method is for separation of lignin from original black liquor (BLIN) and has the following phases in sequence. A first precipitation phase (PR1) for precipitation of lignin by a first acidification of the original black liquor by adding a first acid or mixture of acids (G1a) followed by a first storage phase wherein precipitated lignin particles are allowed to increase in size, followed by a second precipitation phase (PR2) for precipitation of lignin by a further acidification of the original black liquor by adding a second acid or mixture of acids (G1b). By retaining the acidified black liquor for at least 25 minutes in the storage phase are the precipitated lignin particles allowed to grow in size and the filterability is improved considerably.

Abstract: The method is for separation of lignin from original black liquor (BLIN) having a first precipitation phase (PR1/PR2) for precipitation of lignin by a first acidification using acidifier, CO2, at alkaline conditions, then separating a lignin cake with subsequent suspension of the lignin cake in a strong acid to leach our metals from the lignin followed by dewatering and obtaining a clean lignin product LP. The acidic liquid phase (FL1) subjected to a sulphur removal process wherein a calcium containing compound is added to the acidic liquid phase, whereby sulphur in the acidic liquid phase is reacting with the calcium compound forming solid gypsum which could be separated and bled off from the process. The remaining acidic liquid could then be returned to the recovery process without negatively affecting the sulphur balance of the mill.

Abstract: The method is for separation of lignin from original black liquor (BLIN) having the following phases in sequence; a first precipitation phase (PR1) for precipitation of lignin by a first acidification of the original black liquor by adding a first acid or mixture of acids (G1a); followed by a second precipitation phase (PR2) for precipitation of lignin by a further acidification of the original black liquor by adding a second acid or mixture of acids (G1b). The first phase is implemented to lower the pH while avoiding any larger amount of precipitation, i.e. less than 2-5%, while the second phase is implemented in order to obtain the larger part of the precipitation. In total is 40-70% of the total lignin content of the original black liquor precipitated while the residual black liquor after precipitation is still strongly alkaline.

Abstract: The method is for separation of lignin from original black liquor. Lignin is precipitated in a first acidification stage followed by dewatering a first lignin suspension while forming a first filter cake. The first lignin filter cake is suspended in a second acidification stage whereupon a second lignin suspension is obtained. The second lignin suspension is dewatered to form a second filter cake. The second filter cake is washed and the washed second lignin cake is dewatered to obtain a lignin product. Waste gases from the second acidification stage is recirculated back to the first acidification stage and mixed with the original black liquor.