Due to the fact that the fermentation broth contains a large amount of bacteria, proteins and macromolecular organic substances, the traditional separation, concentration and filtration methods mainly include vacuum drum filtration, plate and frame pressure filtration, etc. However, these methods can only produce mycelium in the fermentation broth. Solid impurities and other solids can be removed, but soluble proteins, organic matter, etc. cannot be separated.
Furthermore, since the fermentation broth contains various pigments, the presence of these pigments affects the analysis of L-alanine, leading to analytical errors and a decrease in the purity of the target product. Therefore, they must be removed during the purification process. Due to the simplicity and ease of operation of activated carbon equipment, traditional methods use activated carbon to remove pigments from the fermentation broth. However, the adsorption capacity of activated carbon is limited and it is not easy to regenerate. The main methods currently adopted include nanofiltration and adsorption resin methods, etc. Resin adsorption decolorization usually occurs after the concentration of the fermentation broth. If resin adsorption decolorization is carried out before the concentration of the fermentation broth, the required elution dose will be larger and the treatment time will be longer. Generally speaking, it is not recommended for use.
Laboratory membrane separation
With the progress of The Times and the development of science and technology, membrane separation technology, with its unique separation advantages, has achieved the separation of mixtures with different particle sizes and plays an important role in the field of fermentation liquid separation. Therefore, combining membrane separation technology with the traditional fermentation broth production process is a very good technology.
Traditional "fermentation production" process:
Traditional process: Biological fermentation to produce alanine (non-alanine sodium) - after cooling - sterilization by plate and frame or other processes - decolorization by plate and frame activated carbon - triple-effect evaporation crystallization
Laboratory membrane separation process:
Biological fermentation, high-temperature sterilization (no need for cooling), ceramic membrane filtration, nanofiltration, desalination and decolorization, single-effect evaporation, mother liquor, nanofiltration membrane decolorization, evaporation and crystallization
Characteristics of laboratory membrane process:
In this fermentation process, alanine is directly produced without the steps of adjusting alkali or PH. The operation is simple and the production cycle is short.
2. The cooling step is saved, and the ceramic membrane process can remove most of the protein, increase the light transmittance. Subsequently, membrane desalination and decolorization are adopted, which reduces the labor operation cost and improves the product quality. The application of decolorization membrane in the mother liquor increases the yield of L-alanine and reduces energy consumption.
3. Three To a large extent, it saves the time for equipment cleaning and effectively shortens the production cycle.
4. The bacterial liquid in the fermentation broth is recycled and reused, while the clear liquid is processed into finished products. Try to minimize the waste of resources.
5. Ceramic membranes have a good sterilization effect, with a sterilization filter rate of over 99%, which is more advantageous than traditional high-temperature sterilization methods.
