Upflow settling reactor for enzymatic hydrolysis of cellulose

An enzyme composition comprising cellulase enzymes and one or more than one flocculent, for hydrolyzing cellulose to glucose, cellobiose, glucose oligomers, or a combination thereof, wherein the hydrolysis is carried out by:

• i) providing an aqueous slurry of the pre-treated cellulosic feedstock, the slurry comprising from about 3% to about 30% undissolved solids in a liquid, the undissolved solids comprising at least about 20% cellulose;
• ii) introducing the aqueous slurry at the bottom of a hydrolysis reactor and limiting axial dispersion in the reactor by avoiding mixing, and maintaining an average slurry flow velocity of about 0.1 to about 20 feet per hour, such that the undissolved solids flow upward at a rate slower than that of the liquid;
• iii) adding the enzyme composition to the aqueous slurry before or during the step of introducing (step ii);
• and
• iv) removing an aqueous stream comprising hydrolysis product and unhydrolyzed solids from the hydrolysis reactor, the hydrolysis product comprising glucose, cellobiose, glucose oligomers, or a combination thereof.

The use of an enzyme composition comprising cellulase enzymes and one or more than one flocculent for the enzymatic hydrolysis of cellulose to produce a hydrolysis product from a pre-treated cellulosic feedstock, the use of the enzyme composition comprising:

• i) providing an aqueous slurry of the pre-treated cellulosic feedstock, the slurry comprising from about 3% to about 30% undissolved solids in a liquid, the undissolved solids comprising at least about 20% cellulose;
• ii) introducing the aqueous slurry at the bottom of a hydrolysis reactor and limiting axial dispersion by avoiding mixing, at an average slurry flow velocity of about 0.1 to about 20 feet per hour, such that the undissolved solids flow upward at a rate slower than that of the liquid;
• iii) adding the enzyme composition to the aqueous slurry before or during the step of introducing (step ii);
• and
• iv) removing an aqueous stream comprising hydrolyzed product and unhydrolyzed solids from the hydrolysis reactor, the hydrolysis product comprising glucose, cellobiose, glucose oligomers, or a combination thereof.

A kit comprising cellulase enzymes, one or more than one flocculent, and instructions for hydrolyzing cellulose to produce a hydrolysis product from a pre-treated cellulosic feedstock, the instructions comprising:

• i) providing an aqueous slurry of the pre-treated cellulosic feedstock, the slurry comprising from about 3% to about 30% undissolved solids in a liquid, the undissolved solids comprising at least about 20% cellulose;
• ii) introducing the aqueous slurry at the bottom of a hydrolysis reactor and limiting axial dispersion by avoiding mixing, at an average slurry flow velocity of about 0.1 to about 20 feet per hour, such that the undissolved solids flow upward at a rate slower than that of the liquid;
• iii) adding the cellulase enzymes and the one or more than one flocculent to the aqueous slurry before or during the step of introducing (step ii);
• and
• iv) removing an aqueous stream comprising hydrolyzed product and unhydrolyzed solids from the hydrolysis reactor, the hydrolysis product comprising glucose, cellobiose, glucose oligomers, or a combination thereof.