Method for producing lactic acid from bagasse

The invention discloses a method for producing lactic acid from bagasse. The method comprises the following steps: grinding and filtering bagasse: adding water to the bagasse, carrying out wet grinding on the bagasse by virtue of a disc mill and sieving the bagasse; carryin gout green liquor-ethanol coupling pretreatment: carrying out a pretreatment course in a pressure-proof reaction kettle, adding the ground bagasse to the reactor and adding a green liquor, wherein heating temperature is 140-145 DEG C and reaction duration is 2-4h; filtering after the pretreatment so as to obtain solid residues; carrying out synchronous saccharification and fermentation: adding cellulase and lactobacillus strain to the solid residues obtained from pretreatment in a mode of taking the solid residues as a fermentation substrate, and reacting at 45 DEG C at pH value of 4.8-5.0 for 72-96h so as to produce the lactic acid. The method for producing the lactic acid from bagasse disclosed by the invention is high in conversion rate of hydrolyzing cellulase into cellulose and semi-cellulose; and the utilization rate of bagasse resource component is high and production cost is low.