Process for enzymatic hydrolysis of lignocellulosic material and fermentation of sugars

Process for preparation of a fermentation product from lignocellulosic material, comprising:

• a) optionally, pretreatment of the lignocellulosic material;
• b) optionally, washing of the optionally pretreated lignocellulosic material;
• c) fed-batch addition of the optionally washed and/or optionally pretreated lignocellulosic material to a first container that comprises an enzyme composition comprising at least two cellulases;
• d) enzymatic hydrolysis of the optionally washed and/or optionally pretreated lignocellulosic material in the first container using the enzyme composition comprising at least two cellulases to liquefy the lignocellulosic material;
• e) addition of the liquefied lignocellulosic material to a second container;
• f) enzymatic hydrolysis of the liquefied lignocellulosic material in the second container using an enzyme composition comprising at least two cellulases to obtain a hydrolysed lignocellulosic material;
• g) optionally, recovery of the hydrolysed lignocellulosic material;
• h) fermentation of the hydrolysed lignocellulosic material to produce a fermentation product;
• and
• i) optionally, recovery of the fermentation product.