Phosphoric acid-sulphurous acid clarification process segmented preliming method

The invention discloses a phosphoric acid-sulphurous acid clarification process segmented preliming method, and belongs to the technical field of a sugar refining industry clarification process. The preliming method is characterized in that mixed juice is firstly subjected to normal temperature preliming, so that acidic amino acid such as collagen and caseinum is condensed; then, first heating isperformed to 60 to 68 DEG C; secondary lime addition is performed (the pH value is controlled to be 7.8 to 8.0); pigment, silica gel and the like are condensed; third lime addition is performed (the pH value is controlled to be 8.5 to 9.5, and the temperature is 65 to 75 DEG C), so that arginine, lysine, histidine and the like are condensed. Different condensation points of colloform are used, sothat the colloform is condensed at sub stages; under the heating effect, further consolidation is performed; meanwhile, the colloform redissolution and the sugar conversion loss due to the low pH value in the stoving process a