Citric acid (C₆H₈O₇) is one of the most important products in the production of organic acids by fermentation. It is widely used in food, chemical, pharmaceutical, environmental protection and other industries, and plays an important role in national economic production. China's citric acid industry is at the world's leading level in fermentation technology, especially strains and production processes, but the downstream extraction process is relatively backward, which seriously restricts the development of the industry.
The composition of citric acid fermentation liquid is complex. In addition to the product, it also contains various impurities such as bacteria, residual sugar, pigments, proteins, etc., which makes the extraction process very difficult. The global citric acid industry generally faces a situation of "high production and low income", and the extraction process has become a key bottleneck restricting the development of the industry.
Comparison of Traditional Extraction Methods
The commonly used citric acid extraction methods are:
1.Calcium salt method: mature process but complex operation, low yield, high energy consumption and serious pollution.
2.Ion exchange method: low energy consumption but the resin needs to be regenerated frequently, generating a large amount of waste liquid.
3.Membrane separation method: high selectivity but low flux, difficult to industrialize.
4.Solvent extraction method: compared with calcium salt method, it saves raw materials and is environmentally friendly, but there are problems of low extraction rate and equipment corrosion.
Innovative Solutions for Centrifugal Extraction Technology
Zhengzhou Tiei Extraction Technology Co., Ltd. has developed a new method for extracting citric acid using the centrifugal extractor to address the shortcomings of existing technologies, effectively solving the problem of low extraction rate of traditional solvent extraction methods. The core process uses an optimized amine mixed extractant, and after a 5-stage countercurrent extraction process, the extraction rate is as high as 97.36%, achieving the best extraction effect at an operating temperature of 35°C.
Citric Acid Extraction Process
1.Extraction section: amine extractant to fermentation liquid volume ratio 1-6:1, 5-stage countercurrent extraction at 35°C.
2.Washing section: organic phase to water volume ratio 10-30:1, 2-stage countercurrent washing at 30-35°C.
3.Stripping: organic phase to water volume ratio 5-10:1, 4-stage countercurrent stripping at 50-55°C.
Compared with the calcium salt method, this process reduces waste residue discharge, the closed system reduces solvent volatilization, and the extractant can be recycled to reduce consumption. The core equipment, the CWL-M centrifugal extractor, adopts an upper-hung drum design and a fully composite material corrosion-resistant structure (PP, PFA material), which has a strong mixing-mass transfer efficiency.
This technology has been successfully applied in many citric acid production companies, bringing significant benefits: product purity increased to more than 99.0%; comprehensive yield increased by 15-20%; energy consumption reduced by about 30%; wastewater discharge reduced by more than 50%; equipment footprint reduced by 40%.
Zhengzhou Tiei Extraction Technology Co., Ltd. will continue to be committed to the innovative research and development of separation and extraction technology, and provide more efficient and environmentally friendly solutions for industries such as citric acid. We welcome customers to consult and cooperate to jointly promote technological progress in extraction technology.
Email: sales@tieiextraction.com
Whatsapp: +86 19069612820
