Meckey High Return Fully Automatic Fermentation Lactic Acid Production Line Equipment
2.0 Process flow block diagram
3.0 Technical description
1) Seed production
After liquefaction, the glucose is sent to the seed tank to adjust the DS value and pH, sterilization and cooling, then for the bacterial growing. The strains fermentation is with high temp resistant and high production yield.
2) Fermentation
The glucose from glucose workshop is sent to the fermentation tank to adjust the DS value and pH, sterilization and cooling to 35ºC, add nitrogen, strain and Ca(OH)2. Adding the seed to the fermentation tank by the sterilized piping for the fermentation with sterile air feeding continuously.
3) Flocculation
The fermentation liquid is pumped into tube type heat exchanger for heating temperature to 85~90ºCwith steam, then mixed with the prepared flocculant in dynamic mixer, the flocculation and sedimentation is completed in flocculation tank. Pay attention the pH of flocculation tank, it can be adjusted slightly with Ca(OH)2 if it can't meet requirement.
4) Filtration
Besides the calcium lactate product, there are some impurities, such as mycelium. Filtering the impurities is the 1st step to make sure the lactic acid quality. The mycelium after washing is sold to the feed production. And the filtrate is thin calcium lactate for concentration.
5) MVR calcium lactate concentration
The above calcium lactate solution is concentrated by MVR evaporator, so as to save energy.
6) Acid hydrolysis and vacuum belt filter
The dissociation constant of calcium lactate increases with the increase of H+ concentration under acidic conditions, double decomposition reaction occurs in the solution of strong acid (sulfuric acid), thus the gypsum CaSO4 which is difficult to dissolve in water will be produced, and weak acid (lactic acid) dissociates and dissolves in solution, which is the acidolysis solution.
Chemical reaction equation is as below:
(C3H5O2O)2Ca+H2SO4=CaSO4+ 2(C3H5O2OH)
The water ring vacuum pump is used to generate vacuum, and the pressure difference is formed on both sides of the filter cloth, so as to achieve the purpose of solid-liquid phase separation.
The CaSO4 is filtered out by the belt vacuum filter to get the CaSO4 crystalline for selling to the gypsum production. And the lactic acid is sent to the next section.
7) Powder active carbon decolor and filtration section
Adding active carbon to the acidolysis solution with agitating for the decoloring. Then to the next refinery section.
8) Decoloring process
The lactic acid is decolored by the absorption of granule active carbon, so as to lower than the chroma.
9) Ion exchange
The filtrate of above section is sent to ion exchangers for removing cation and anion as well as bad odor and soluble impurities to get refined lactic acid.
10) Nanofiltration membrane filtration process
The lactic acid was separated and purified by a complete set of nanofiltration membrane filtration equipment
11)MVR evaporation
After filtering by the check filter, the lactic acid is sent to the evaporator to get high DS value of product.
12) Molecular distillation process
The concentrated lactic acid 50~55% will be further separated and purified through the molecular distillation system under the control of stable flow rate, so as to obtain Thermostabilization grade of lactic acid.
13) Packing
After molecular distillation, packing the product according to different requirement by packing machine