Process Scope
Liquid glucose→ lactic acid fermentation→ crude extract→refine extraction →products
1 Fermentation workshop
1.1 Design program
The liquid glucose liquid provided by the sugar workshop is used as the carbon source, plus the organic nitrogen source, and adding the qualified bacteria after cultivation, the lactic acid fermentation liquid is continuously accumulated according to the process control.
1.2 Production method
The sugar liquid of the sugar workshop is used as the fermentation carbon source, plus nitrogen source and qualified bacteria, adding calcium hydroxide, the coil inside and outside the fermenter is used for cooling, by which the fermentation temperature, PH and tank pressure are controlled for lactic acid fermentation.
During the production process, the performance of the strain changes due to the spontaneous mutation of the strain. In order to maintain the stability of the strain performance, it is necessary to separate and purify the original strains regularly, and the purpose is to eliminate the declining strains and select the high yield and excellent strains for production use.
1.3 Fermentation process
Using the metabolic effects of the bacteria to maximize the accumulation of lactic acid.Through the continuous elimination of sugar liquid, seed tank culture and fermentation tank cultivation process, the massive accumulation process of lactic acid is completed, so as to achieve the purpose of high yield of acid, high conversion rate, low residual sugar, low cycle and low energy consumption.
2 L-crude lactic acid extraction workshop
2.1 design program
The workshop uses calcium lactic acid fermentation liquid from fermentation workshop, with calcium hydroxide and concentrated sulfuric acid as auxiliary materials, using continuous heating flocculation, automatic plate and frame filtration, MVR concentration, continuous acid lysis, continuous decolorization and other processes to produce crude L-lactic acid production line.
2.2 Production method
2.2.1 Flocculation process description
The fermentation liquid is entered into the column tube heater through the fermentation liquid conveying pump, heated to 85℃ -90℃ by steam, and then mixed with the flocculanting agent to the flocculation tank for flocculation and settlement.Observe the pH value of the flocculation tank. If the pH value does not meet the requirements, the pH value can be slightly adjusted with calcium hydroxide.
2.2.2 Fermentation liquid filtration process
Under the pressure of the feed pump, the fermentation liquid is transported into each filter chamber to separate the solid and liquid through the filter medium.Form a filter residue on the filter cloth until the filter chamber is filled to form a filter cake.The filtrate passes through the filter cloth and will discharge together along the filter plate channel.After filtration, the washing water can be used to wash the filter slag.After washing, compressed air is introduced to remove the remaining washing fluid.After the filter is finished, open the filter press to remove the filter cake (the filter cake is stored in two adjacent filter plates), clean the filter cloth, and press the plate filter again to start the next working cycle.
2.2.3MVR calcium lactate concentration process
The filtered calcium lactate is concentrated by MVR steam compressor to save energy.
2.2.4 Acid solution process and belt vacuum filtration process
Under the acid condition of calcium lactate, its dissociation constant increases with the increase of H + concentration, and the compound decomposition reaction in the solution of strong acid (sulfuric acid), forming insoluble gypsum (CaSO4) precipitation, and the weak acid (lactic acid) free, dissolved in the solution is the acid solution.
Chemical reaction equation: (C3H5O2O)2Ca+H2SO4=CaSO4+ 2(C3H5O2OH)
Using water ring vacuum pump to produce vacuum, the pressure difference on both sides of the filter cloth, so as to achieve the purpose of solid and liquid phase separation.
2.2.5 Powder carbon decolorization filter process
Under the pressure of the feed pump, the decolorization liquid pump is transported into each filter chamber to separate the solid and the liquid through the filter medium.Form a filter residue on the filter cloth until the filter chamber is filled to form a filter cake.The filtrate passes through the filter cloth and will discharge centrally along the filter plate channel.After filtration, the washing water can be used to wash the filter slag.After washing, compressed air is introduced to remove the remaining washing fluid.After the filter is finished, open the filter press to remove the filter cake (the filter cake is stored in two adjacent filter plates), clean the filter cloth, and press the plate filter again to start the next working cycle.
3.L-lactic acid refine extraction workshop
3.1 Design program
The workshop uses lactic acid solution from the crude extraction workshop, using further decoloration, ion exchange, membrane filtration, MVR lactic acid concentration, and molecular distillation to produce refined L-lactic acid production line.
3.2 Production method
3.2.1 Colorprocess description
Crude lactic acid further reduces the chromaticity through the adsorption of granular activated carbon.
3.2.2 Ion exchange process
Under the pressure of the feed pump, the fermentation liquid is transported into each ion exchange column, and kation in the lactic acid solution are removed through the ion adsorption of the cation exchange column and anion exchange column.
3.2.3. Nanofiltration membrane filtration process
Lactic acid was separated and purified by a complete set of nanofiltration membrane filtration equipment.
3.2.4MVR lactic acid concentration process
Through the MVR steam compressor complete concentration equipment, the lactic acid is concentrated after ion changer, to save energy.
3.2.5 Molecular distillation process
Under controlling the stable flow rate, the concentrated lactic acid liquid enters the molecular distillation system to further separate and purify the lactic acid to reach the thermal stable level of lactic acid.
3.2.6 product packaging
Use the automatic packaging system, packaging according to different specifications.