The invention relates to a method for preparing bioethanol by utilizing
kelp processing waste. The method comprises the following steps: firstly cleaning the
kelp processing waste, homogenizing, sterilizing and preparing p pretreatment liquid; further carrying out
hydrolysis saccharification on the pretreatment liquid: adding activated
trichoderma viride
fermentation liquid according to the volume ratio of 5-20% or / and adding
cellulase according to the weight-volume ratio of 0.5-1g / L for carrying out the
hydrolysis saccharification on the pretreatment liquid, wherein the temperature for the
hydrolysis saccharification is 45-55 DEG C, the pH is 5-7 and the time is 36-48h; further adding well activated
saccharomyces cerevisiae zymocyte into liquid after the hydrolysis saccharification according to the volume ratio of 10-20% for
fermentation, and preparing
ethanol, wherein the
fermentation temperature is 25-35 DEG C, the pH is 4-6 and the fermentation time is 50-60h; and carrying out liquid-
solid separation on the fermentation liquid after the fermentation is finished, and evaporating out the
ethanol from supernatant fluid in the reduced pressure
distillation method. The method has simple process and low cost, and can not only solve the environmental
pollution problem of the
kelp processing waste, but also provide a new material source for large-scale production of the
ethanol and promote the development of marine
biomass energy.