Electrodialysis has been successfully applied to the project of 10m/h of gamma-aminobutyric acid stock solution for desalination and concentration

The industrial project of desalinating and concentrating the original solution of gamma-aminobutyric acid (GABA) by electrodialysis technology has achieved a complete success. The raw liquid flow rate processed by this project is as high as 10m³/h, marking a major breakthrough in electrodialysis technology in the field of high-flow and continuous biological product refining. It provides a brand-new energy-saving and environmentally friendly separation and purification solution for the natural product, amino acid and food additive industries.

I. Project Background and Industry Pain Points

Gamma-aminobutyric acid (GABA), as an important functional amino acid, is widely used in the fields of medicine, health food and animal feed, etc. After its fermentation or chemical synthesis, the GABA raw liquid obtained usually contains a large amount of inorganic salts (such as ammonium salts, sulfate ions, etc.) and has a relatively low concentration. It must undergo desalination and concentration to meet the standards of high-purity products.

Traditional desalination and concentration processes, such as the ion exchange resin method, are effective but have problems like cumbersome operation, large consumption of acid and alkali for regeneration, generation of a large amount of wastewater, and high operating costs. Especially for large flow rates like 10m³/h, traditional methods take up a large area of equipment, and intermittent operations are difficult to meet the demands of continuous production, which has become a bottleneck restricting production capacity and cost control. Therefore, the industry urgently needs a continuous and clean production technology.

Ii. Electrodialysis Technology: Principle and Outstanding Advantages

It was under this background that electrodialysis technology was successfully applied. The core principle lies in the utilization of the selective permeability of ion-exchange membranes and the directional driving effect of direct current electric fields.

The electrodialysis device is composed of a series of anion exchange membranes and cation exchange membranes alternately arranged to form concentrated chambers and dilute chambers. After being electrified, inorganic salt ions in the GABA stock solution (such as NH₄⁺, Cl⁻, SO₄²⁻, etc.) undergo directional migration under the action of the electric field force: cations move through the cation membrane towards the cathode, and anions move through the anion membrane towards the anode. However, since GABA mainly exists in the form of amphoteric ions under the adjustment of solution pH value, its net charge is zero and its mobility is very weak, thus it is retained in the dilute chamber.

In this way, GABA solution with the vast majority of inorganic salts removed can be obtained at the outlet of the dilute chamber, while the salts are concentrated in the concentrated chamber and discharged as wastewater. Through multi-stage series connection, deep desalination and synchronous concentration of GABA solution can be achieved (removed through the electroosmotic effect of water in the dilute chamber), achieving two goals at once.

Compared with traditional techniques, electrodialysis technology has demonstrated significant advantages in this project:
1. Continuous operation: It can run stably for 24 hours continuously, perfectly matching the large flow processing demand of 10m³/h. With a high degree of automation, it significantly increases production capacity.
2. Extremely low operating costs: The main energy consumption of the process is electricity, and there is no need for expensive acid and alkali reagents for regeneration, significantly reducing raw material costs and hazardous waste treatment expenses.
3. Environmentally friendly: No acid or alkali waste liquid is discharged. The entire process is clean and environmentally friendly, in line with the development concept of green manufacturing.
4. High product yield and excellent quality: GABA is a non-charged molecule with minimal loss, and the yield can reach over 95%. At the same time, it avoids the impurities and denaturation that may be introduced in traditional processes, and the product purity is high.
5. Synchronous concentration: While desalinating, it can also concentrate the product to a certain extent, reducing the load on subsequent evaporation and concentration, and further saving energy.

Iii. Project Achievements and Future Prospects

The successful commissioning of this 10m³/h project has demonstrated the technical feasibility and economic superiority of electrodialysis technology in treating large-flow amino acid solutions. User feedback indicates that the system operates stably, with a desalination rate exceeding 95%. The ash content of the product has significantly decreased, and the purity has greatly improved, fully meeting the demands of the high-end market. Meanwhile, the comprehensive operating cost has decreased by approximately 30% to 40% compared to the old process, with a short payback period and significant economic benefits.

The successful case of this project has played a very strong exemplary role for the entire bio-fermentation and fine chemical industry. It not only solves the specific problems in GABA production, but also demonstrates a universal technical path. Many similar products, such as other amino acids, organic acids, sugar alcohols, plant extracts, etc., all face challenges of desalination and concentration in their production processes.

Conclusion

The successful application of electrodialysis technology in the high-flow desalination and concentration project of aminobutyric acid is a model of how separation membrane technology can empower the upgrading of traditional industries. With its outstanding advantages of energy conservation and environmental protection, it is gradually replacing the traditional unit operations that are high energy-consuming and highly polluting, and has become an indispensable core technology in modern biomanufacturing and food deep processing. With the continuous advancement of membrane material technology and the optimization of system design, the application boundaries of electrodialysis technology will continue to expand, injecting strong impetus into the quality improvement, efficiency enhancement and sustainable development of more industries.