Bleaching and pulping process of waste distiller's grains

The invention provides a bleaching and pulping process for waste distiller's grains of Baijiu. The bleaching and pulping process comprises the following steps: S1, cooking and pulping the waste distiller's grains of the Baijiu by adopting a sulfate method to obtain waste distiller's grain pulp; s2, after the waste vinasse pulp forms raw pulp, D0-section bleaching, E-section bleaching and D1-section bleaching are sequentially carried out, and bleached pulp is obtained; the final bleaching pH of D0 section bleaching is 1-5, the use amount of C1O2 is 1-6% of the mass of the oven-dry waste vinasse pulp, and bleaching treatment is carried out for 10-120 min at the temperature of 50-90 DEG C; e-section bleaching: washing the D0-section bleaching slurry to be neutral, then mixing the D0-section bleaching slurry with alkali liquor, and performing bleaching treatment at 70 DEG C for 60 minutes; in the step of D1-stage bleaching, the E-stage bleaching slurry is washed to be neutral, and the use amount ...