Patent ID: 8545685
Filing Date: 2013-10-01
Classification: B01D,C07C,C12N,C12P

Abstract:
1. A cleaning process of producing lactic acid, comprising: preparing a saccharification liquid through saccharated materials; fermenting, by a fermentation unit, with nutritive materials and a lactic acid bacteria, forming a fermentation broth; adjusting the pH using a liquid alkali; pumping the fermentation broth into a ceramic membrane when a mass percentage concentration of a sugar content reaches a designated amount; filtrating the fermentation broth with the ceramic membrane, wherein an intercepted retentate forms an interception liquid; reintroducing the interception liquid into the fermentation unit for recycling; feeding a permeate from the ceramic membrane to a nanofiltration unit to be decoloured and purified, wherein an intercepted nanofiltration retentate forms a concentrated solution; introducing the concentrated solution into a sterilization system wherein the concentrated solution from the nanofiltration unit and a fermentation unit cleaning liquid are filtrated by a sterilization system ceramic membrane to remove hybrid bacteria before reintroducing the concentrated solution into the fermentation unit for recycling; subjecting the permeate from the nanofiltration unit to a bipolar electrodialysis system to prepare lactic acid, and the liquid alkali produced at the same time is reintroduced into the fermentation tank for recycling; and concentrating the lactic acid by using vacuum distillation.