Method for introducing cellulase enzyme to lignocellulosic feedstock slurry

A method for producing glucose from a lignocellulosic feedstock, said method comprising the steps of:

• (i) providing a pretreated lignocellulosic feedstock slurry in which at least a portion of the hemicellulose has been hydrolyzed during pretreatment;
• (ii) moving the pretreated slurry through a pipe, which pretreated slurry has an undissolved solids content of between about 15 and about 30 wt %;
• (iii) optionally adjusting the pH of the pretreated slurry to a value that is compatible with cellulase enzyme;
• (iv) adding cellulase enzyme to said pretreated slurry to produce a slurry comprising cellulase enzyme, while maintaining the undissolved solids content of said pretreated slurry between about 15 and about 30 wt %;
• (v) dispersing the cellulase enzyme added in step (iv) in said pretreated slurry by using a high shear in-line mixing device so as to impart shear to said pretreated slurry, thereby producing a pretreated slurry in which the cellulase enzyme is dispersed, which high shear in-line mixing device comprises one or more mixing element, wherein the ratio of the cross-sectional area of the one or more mixing element to the cross-sectional area of the pipe in the same lateral plane is between 0.01 and 2;
• and thereafter
• (vi) subjecting the pretreated slurry resulting from step (v) comprising dispersed cellulase enzyme to hydrolysis so as to produce glucose from cellulose contained therein.

A method for producing glucose from a lignocellulosic feedstock, said method comprising the steps of:

• (i) providing a pretreated lignocellulosic feedstock slurry in which at least a portion of the hemicellulose has been hydrolyzed during pretreatment;
• (ii) moving the pretreated slurry through a pipe, which pretreated slurry has an undissolved solids content of between about 15 and about 30 wt %;
• (iii) optionally adjusting the pH of the pretreated slurry to a value that is compatible with cellulase enzyme;
• (iv) adding cellulase enzyme to said pretreated slurry to produce a slurry comprising cellulase enzyme, while maintaining the undissolved solids content of said pretreated slurry between about 15 and about 30 wt %;
• (v) dispersing the cellulase enzyme added in step (iv) in said pretreated slurry by using a high shear in-line mixing device so as to impart shear to said pretreated slurry, thereby producing a pretreated slurry in which the cellulase enzyme is dispersed, wherein the residence time of the pretreated slurry in the high shear in-line mixing device is between 0.1 s and 60 s;
• and thereafter
• (vi) subjecting the pretreated slurry resulting from step (v) comprising dispersed cellulase enzyme to hydrolysis so as to produce glucose from cellulose contained therein.

A system for producing glucose from a lignocellulosic feedstock, the system comprising:

• (i) a pretreatment reactor for receiving the lignocellulosic feedstock slurry and hydrolyzing hemicellulose present in said feedstock therein, thereby producing a pretreated lignocellulosic feedstock;
• (ii) an enzyme addition device downstream of said pretreatment reactor for adding cellulase enzyme to the pretreated lignocellulosic feedstock;
• (iii) a pipe for receiving the pretreated feedstock and a high shear in-line mixer for receiving and imparting shear to said pretreated slurry, thereby producing a pretreated slurry in which the cellulase enzyme is dispersed;
• (iv) one or more unmixed hydrolysis reactors for receiving and partially hydrolyzing the pretreated slurry in which the cellulase enzyme is dispersed so as to produce a mixture of partially hydrolyzed cellulose;
• and
• (v) one or more downstream mixed hydrolysis reactors for receiving the partially hydrolyzed cellulose continuing the hydrolysis of the mixture to produce the glucose.

A method for producing glucose from a lignocellulosic feedstock, said method comprising the steps of:

• (i) providing a pretreated lignocellulosic feedstock slurry;
• (ii) moving the pretreated feedstock slurry through a pipe, which pretreated slurry has an undissolved solids content of between about 15 and about 30 wt %;
• (iii) adding cellulase enzyme to said pretreated slurry to produce a slurry comprising cellulase enzyme;
• (iv) dispersing the cellulase enzyme added in step (iii) in said pretreated slurry by using a high shear in-line mixing device, thereby producing a pretreated slurry comprising dispersed cellulase enzyme;
• and thereafter
• (v) subjecting the pretreated slurry comprising dispersed cellulase enzyme to hydrolysis so as to produce glucose from cellulose contained therein.