Studies On Concentration Of 2KLG By Nonafiltration

2-keto - L-gulonic acid (listed 2KLG) is an important intermediate in the production of vitamin C (VC). In the process, it is the key to improve the product quality and reduce the cost that 2KLG will be effective extracted, separated and purified. The traditional concentration of 2KLG used the three-effect evaporation process. There are some shortcomings as the low initial concentration ,the long evaporation cycle and the higher steam consumption ,and so on.Nanofiltration technology is first applied in the concentration of 2KLG . It has been researched that the application of NF in the VC production , the NF membrane fouling and the method about the membrane pollution.First, four NF membranes(NF-A, NF-B, NF-C,NF-D) have been tested in the concentration of 2KLG .It has been compared with the four membranes about the operating parameters, filtering yield, flux and the retention and concentration ratio of the concentration effect. The results show that the concentrate quality and yield for NF-B are more excellent than the others used in the experiment. The yield , the concentration times and the membrane flux are up to 97.72%, 2.56, 10.68m3/hr, (2.0~2.5MPa, operating temperature 20°C).On this basis, the membrane fouling and cleaning have been studied.The configurations of the foulants on the membrane surface have been investigated qualitatively by SEM. The effects of the different chemical agents have been compared. The experimental results show that the cleaning agent (S-001, S-002) are more effective than the others in the recovery of the membrane system. After cleaning ,the flux recovery rate reached 97.8%(S001), 88.4% (S002).The suitable operating pressure is 0.27MPa. The effects of different cleaning reagents have been. Compared.