Method for improving drainability of cotton stalk chemi-mechanical pulp

The invention discloses a method for improving drainability of cotton stalk chemi-mechanical pulp, and belongs to the field of pulping and papermaking. The method comprises the following steps: crushing, washing and steaming cotton stalks, adding a section of chemical impregnation agent, and then carrying out mechanical dissociation to obtain a cotton stalk material; carrying out enzyme pretreatment on the cotton stalk material by adopting pectinase to obtain a pretreated material; adding a second-stage chemical impregnation agent into the pretreated material, performing mechanical dissociation, and then performing defibrination dissociation to obtain a defibrinated material; and washing the pulp grinding material, and carrying out enzyme treatment on the pulp grinding material by adopting pectinase to obtain the cotton stalk chemi-mechanical pulp with obviously improved water filtration property. The pectinase is selected as a biological enzyme, and a pectinase two-stage treatment process is designed, so tha