▎ 摘　　要

NOVELTY - Preparing polylactic acid fiber using combined plant comprises (A) taking the combined plant, shell powder and graphene, fermentation to obtain fermentation liquid, (B) using lime milk to neutralize slight alkalinity of the fermentation liquid, boiling for sterilizing, cooling, filtering and re-crystallizing, (C) slowly adding acetic acid, stirring, filtering, evaporating and concentrating filter liquid, and (D) centrifugation to obtain lactic acid, and (E) dehydration and cyclization the obtained lactic acid to obtain lactide, taking the obtained lactide to ring-opening polymerization. USE - The method is useful for preparing polylactic acid fiber using combined plant (claimed). ADVANTAGE - The method is environmentally friendly and suitable for textile industry. DETAILED DESCRIPTION - Preparing polylactic acid fiber using combined plant comprises (A) taking the combined plant, shell powder and graphene, under action of bio-catalyst, adding pure lactic acid bacteria for fermentation to obtain fermentation liquid, (B) using lime milk to neutralize slight alkalinity of the fermentation liquid, boiling for sterilizing, cooling, filtering and re-crystallizing by hot water, (C) slowly adding acetic acid, stirring, filtering, evaporating and concentrating filter liquid, and (D) centrifugal processing the concentrated liquid at 3500-4500 revolutions/minute to obtain lactic acid, and (E) dehydration and cyclization the obtained lactic acid to obtain lactide, taking the obtained lactide to ring-opening polymerization.