Method for treating cyclization wastewater generated in folic acid production process

Abstract

The invention discloses a method for treating cyclization wastewater generated in a folic acid production process. The method comprises the following steps: cyclization wastewater is subjected to neutralization with calcium hydroxide, and adsorption treatment with macroporous resin, and is continuously applied to cyclization reaction, wherein the cyclization wastewater can be recycled for 8 timeswithout influencing the purity and yield of folic acid crude product; and at the ninth time, the wastewater which is impossible to recycle is mixed with a resin eluent, and is subjected to concentrating treatment, an obtained distillate is subjected to biochemical treatment, and obtained residues are subjected to incinerating treatment. The folic acid production cyclization wastewater amount treated by the method can be reduced by 80%, and the method has remarkable economic benefits and social benefits.

Description

technical field [0001] The invention relates to the technical field of waste water treatment, in particular to a method for treating cyclized waste water produced in the production process of folic acid. Background technique [0002] Folic acid (folic acid or folate), also known as vitamin B9, is a water-soluble vitamin and one of the essential vitamins for life. It has the functions of promoting the maturation of young cells in the bone marrow, anti-tumor, promoting the development of nerve cells and brain cells in infants, preventing stroke, and adjuvant treatment of schizophrenia patients. It is an indispensable nutrient for fetal growth and development. Pregnant women may lack folic acid. It can lead to problems such as low birth weight, cleft lip and palate, and heart defects when the fetus is born. Europe and the United States passed legislation to force the application of folic acid in food, resulting in a sharp increase in the demand for folic acid in the market; th...

AI Technical Summary

Problems solved by technology

[0005] Patent CN105174563A discloses a treatment method of folic acid wastewater: the wastewater is passed into the adjustment tank, the COD and pH value of the wastewater are adjusted by diluting and adding lye, the pretreated wastewater is passed into the coagulation sedimentation tank, and flocculant is added Flocculation and dilution treatment; pass it into the ozone catalytic reaction tank, convert the inhibitory substances present in it into low biochemical toxicity substances, and then pass the waste liquid into the double basement membrane electrodialysis tank for treatment, and the treated wastewater continues to be used; There are several problems in the implementation of this method: (1) reducing the COD of wastewater by dilution will significantly increase the amount of wastewater; (2) folic acid wastewater contains a large amount of sulfate ions and chloride ions, and this method does not involve sulfate ions and The removal of chloride ions, the treatment process is not comprehensive; (3) The data in the description of the examples are not exhaustive, the conditions are not specific, and the experimental results cannot be repeated

[0006] Patent CN106565050A discloses a folic acid wastewater treatment process: the wastewater is filtered, the filtrate is adsorbed by a large-aperture adsorption resin to absorb hydrochloric acid and sulfuric acid, desorbed after backwashing with pure water to obtain a mixed solution of hydrochloric acid and sulfuric acid, and the gaseous membrane method is used to remove ammonia from the ammonia nitrogen wastewater. ammonia nitrogen, ammonia nitrogen and sulfuric acid hydrochloric acid solution are neutralized to obtain a mixture of ammonium chloride and ammonium sulfate, and the residual liquid is biochemically treated; there is a big problem in this process, that is, the large-pore resin is used for large-scale resins containing benzene rings and other groups The molecular substance is designed and cannot effectively adsorb hydrochloric acid or sulfuric acid, and it is difficult to achieve the expected effect in actual implementation

[0007] Patent CN 107162347A discloses a treatment method for folic acid wastewater. Firstly, the pH of the wastewater is adjusted, and then the electro-Fenton treatment is performed to reduce the COD of the wastewater, and then biochemical treatment is performed. The data with the best removal rate in the examples are COD89.62%, Ammonia nitrogen 60.54%, total nitrogen 90.04%; in terms of COD before treatment, it was about 10000 ppm, the removal rate was 89.62%, and the COD value after treatment was nearly 1000 ppm, which failed to meet the national third-level emission standard (COD 120 ppm) or Further biochemical treatment takes over the requirements of the discharge standard (COD 300ppm); in addition, the article does not mention how to deal with a large amount of inorganic salts in the waste liquid, which is incomplete

[0008] Patent ZL201510028363.0 discloses a treatment method for vitamin folic acid production wastewater. The folic acid wastewater is pretreated by the facultative oxygen method, then treated by the internal electrolysis-coagulation method, and finally degraded by immobilized purple non-sulfur photosynthetic bacteria to achieve efflux. standard; this method is suitable for laboratory scale, if it is applied to industrial processing, there are disadvantages such as large investment and high operating cost

[0009] In summary, it can be seen that in actual production, neutralization, filtration, dilution, and biochemical methods are mainly used to treat folic acid cyclization wastewater. However, the methods disclosed in the prior art have difficulties in implementation, high costs, or wastewater after treatment The data indicators did not meet the national wastewater discharge standards, so it is necessary to explore a more reasonable and scientific disposal method to solve the pollution problem of folic acid cyclization wastewater

Images