Method for utilizing distillation fractions obtained from distillation of tall oil in btl or cellulose factory

Abstract

The invention relates to a method for utilizing distillation fractions obtained from distillation of tall oil in a BtL plant. The essential feature of the method allows utilization of tall oil obtained from cellulose plants that is processed into different fractions and passed to different points of the BtL process for producing biofuels and utilizing the same in the gasification step and/or energy generation for the BtL process.

1 . A method for utilizing distillation fractions obtained from distillation ( 18 ) of tall oil ( 18 ) in a BtL plant ( 32 ), characterized in that the method utilizes tall oil ( 18 ) obtained from cellulose plants and processed into different fractions and passed to different points of the BtL process for producing biofuels and utilizing the same in the gasification step ( 2 ) and/or energy generation ( 16 ) of the BtL process. 
     
     
         2 . The method of  claim 1 , characterized in that in the method to the refinery unit of the BtL plant ( 32 ) is integrated a fractionating distillation column ( 12 ), wherein the tall oil ( 18 ) is separated substantially into two fractionated streams of tall oil such that the lighter fraction ( 14   a / 14   b ) is processed further into hydrocarbon chains suited for producing high-quality biofuels while the heavier bottoms fraction ( 15 ) is passed to the gasification process ( 2 ) and/or energy generation ( 16 ) of the BtL plant. 
     
     
         3 . The method of  claim 1 , characterized in that in the method the tall oil distillate ( 14   a / 14   b ) separated in the fractionating distillation column ( 12 ) is passed to a clarifier ( 22 ), wherein is separated the fraction that is to be refined and has a composition similar to the HFTL fraction produced in an FT reactor, while the remainder ( 17 ) of the lighter fractions is utilized in energy or hydrogen generation, for instance. 
     
     
         4 . The method of  claim 3 , characterized in that in the method the lighter fractions ( 14   b ) of the tall oil distillate having a composition similar to the HFTL fraction produced in an FT reactor are pretreated ( 26 ) prior to separation in the fractionating distillation column ( 12 ), whereupon after the separation step the lighter fractions ( 14   b ) are passed to a refinery unit ( 27 ) and therefrom further to a hydrocracker ( 28 ). 
     
     
         5 . The method of  claim 1 , characterized in that in the method the heavier tall oil bottoms fraction ( 15 ) received from the distillation column ( 12 ) is pumped to the gasification reactor of the BtL plant ( 32 ), advantageously a high-temperature gasification reactor ( 2 ) and/or, when necessary, is used in energy generation ( 16 ) or is returned for combustion in the lime kiln of the cellulose plant. 
     
     
         6 . The method of  claim 5 , characterized in that in the method the high-temperature gasification reactor ( 2 ) is a pressurized oxygen gasifier whereto is fed the tall oil bottoms fraction ( 15 ) that joins with the gas resulting from the treatment of biomass in the reactor burner and reacts with oxygen thus generating raw syngas. 
     
     
         7 . The method of  claim 1 , characterized in that depending on the amount of tall oil feedstock, the product yield of the BtL plant ( 32 ) increases by 5-50%. 
     
     
         8 . Use of tall oil ( 18 ) as feedstock in a BtL plant ( 32 ) for production of a synthetic biofuel and utilization thereof in the gasification step ( 2 ) of the BtL process and/or in energy generation ( 16 ). 
     
     
         9 . The use according to  claim 8  such that the BtL plant ( 32 ) is advantageously integrated with a cellulose plant, whereby the BtL plant utilizes tall oil ( 18 ) obtained from the plant integrated therewith and, when necessary, from other cellulose plants for producing biofuel and utilizing the same in the gasification step ( 2 ) of the BtL process and/or in energy generation ( 16 ). 
     
     
         10 . The use according to  claim 8  of tall oil ( 18 ) so that the tall oil is separated prior to the gasification step ( 2 ) of the BtL plant ( 32 ) in a fractionating distillation column ( 12 ) into a light tall oil fraction ( 14   a / 14   b ) that is processed together with HFTL fraction obtained from the BtL process. 
     
     
         11 . The use according to  claim 8  of tall oil ( 18 ) so that the tall oil is preprocessed ( 26 ), refined ( 27 ) and passed to a hydrocracker ( 28 ) thereby producing a tall oil fraction ( 14   b ) that is passed forward as a sidestream to the final distillation step of the BtL product for producing a biofuel. 
     
     
         12 . The use according to  claim 8  of tall oil ( 18 ) so that the heavier bottoms fraction ( 15 ) obtained from the distillation column ( 12 ) is utilized in the gasification process ( 2 ) and/or energy generation ( 16 ) of the BtL plant or in the lime kiln of the cellulose plant whereto the BtL plant is integrated. 
     
     
         13 . The method of  claim 2 , characterized in that in the method the tall oil distillate ( 14   a / 14   b ) separated in the fractionating distillation column ( 12 ) is passed to a clarifier ( 22 ), wherein is separated the fraction that is to be refined and has a composition similar to the HFTL fraction produced in an FT reactor, while the remainder ( 17 ) of the lighter fractions is utilized in energy or hydrogen generation, for instance. 
     
     
         14 . The method of  claim 2 , characterized in that in the method the heavier tall oil bottoms fraction ( 15 ) received from the distillation column ( 12 ) is pumped to the gasification reactor of the BtL plant ( 32 ), advantageously a high-temperature gasification reactor ( 2 ) and/or, when necessary, is used in energy generation ( 16 ) or is returned for combustion in the lime kiln of the cellulose plant. 
     
     
         15 . The method of  claim 2 , characterized in that depending on the amount of tall oil feedstock, the product yield of the BtL plant ( 32 ) increases by 5-50%. 
     
     
         16 . The method of  claim 3 , characterized in that depending on the amount of tall oil feedstock, the product yield of the BtL plant ( 32 ) increases by 5-50%. 
     
     
         17 . The method of  claim 4 , characterized in that depending on the amount of tall oil feedstock, the product yield of the BtL plant ( 32 ) increases by 5-50%. 
     
     
         18 . The method of  claim 5 , characterized in that depending on the amount of tall oil feedstock, the product yield of the BtL plant ( 32 ) increases by 5-50%. 
     
     
         19 . The method of  claim 6 , characterized in that depending on the amount of tall oil feedstock, the product yield of the BtL plant ( 32 ) increases by 5-50%. 
     
     
         20 . The use according to  claim 9  of tall oil ( 18 ) so that the tall oil is separated prior to the gasification step ( 2 ) of the BtL plant ( 32 ) in a fractionating distillation column ( 12 ) into a light tall oil fraction ( 14   a / 14   b ) that is processed together with HFTL fraction obtained from the BtL process.