Top Quality Economic Standard Complete VC -Verarbeitungslinie

VC Project Introduction

There are four main processes in the production process of vitamin C, which are fermentation, extraction, conversion and refinery.

1. Fermentation section

The main work is to connect the purified strain ramp into the blank sterile ramp in the strain room and culture to the end point. Then inoculated into triangular flask sterile medium and cultured to the end point. Cultured in kirschner flask medium until the end point. Then the seed liquid prepared by kirschner flask was connected to the sterile medium in the small fermentation tank. After qualified cultivation, the sterile canned and refrigerated, and the sterility check was made. After qualified, the seed was supplied to fermentation.

1st step fermentation is four-stage expansion culture. The first, second and third stages are the expansion of seed solution. Sorbic sugar is obtained by four-stage fermentation. The 1st step seed solution was connected to the first-level sterile medium for culture to the end point, then connected to the second-level sterile medium and the third-level sterile medium for culture to the end point, and the fourth-level sterile medium was connected to fermentation. Control the temp., tank pres., sterile air flow in the fermentation process, and prepare sugar after 1st step fermentation in the fermentation tank reaches the end point.

2nd step fermentation is four-stage expansion culture. The first, second and third stages are the expansion of seed solution. Cologne acid sodium is obtained by four-stage fermentation. The 2nd step seed solution was connected to the first-level sterile medium for culture to the end point, then connected to the second-level sterile medium and the third-level sterile medium for culture to the end point, and the fourth-level sterile medium was connected to fermentation. During the fermentation process, the temp., tank pres., and sterile air flow was controlled, and the PH of the feed liquid was controlled to be slightly acidic, then the material was prepared to be discharged until the fermentation reached the end point.

2. Extraction section

The fermentation liquid is put into the refinery feeding tank and then put into the circulating tank through the oscillating sieve. Start the membrane filtration system for filtration, and discharge the dialysate to the clear liquid tank. When the concentration produced is controlled below 10mg/ml, it is submitted to environmental protection treatment. After desalination by resin, multi-stage concentration, the dialysate enters the crystallizer to cool down and crystallize. Control the crystallization temp.≤5.0, using the centrifuge to the crystallized solid material for solid-liquid separation to get the wet gulonic acid. The separated mother liquid is concentrated twice, cooling and crystallization to 5-10℃. The separated recovered wet cologonic acid and wet cologonic acid enter to the conversion section.

3. Conversion section

After adding quantitative methanol into the ester conversion tank, the concentrated H2SO4 is slowly added with open stirring, and then the accurately measured wet gulonic acid or recovered gulonic acid is added, and the reaction is heated to the end point. After the cooling of the feed material, the conversion reaction is carried out, and the control of the feed material is slightly alkaline in the reaction. When the reaction is reached endpoint, after cooling, the material is cooled to less than 10℃ through the cooling tank for the solid-liquid separation. After the dissolution of Vitamin C sodium, desalting and decoloring by the ion exchange, after multi-concentration, then enter to the crystallization tank for cooling. The methanol mother liquid is sent to the distillation and purification for application. After the crystallized liquid was cooled to below 5.0℃ by cold brine, the material was separated by centrifuge to obtain crude vitamin C. The crude vitamin C can be refined directly or coarsely dissolved with purified water, then refined.

The mother liquor of crude vitamin C is separated to get the 1st recovered vitamin C by concentration, crystallization, cooling and separation, and then dissolved into the desalination equipment for application. The secondary mother liquor was neutralized, alcohol precipitation and cooled, the separated solid cologne acid sodium was refined for desalting. The separated 3rd mother liquor was dealcoholized and then decolorized and desalted into the 1st mother liquor concentration system.

4. Refinery section

According to the ratio of technical requirements, add water to heat up and dissolve crude vitamin C and add carbon to decolorize. After multi-stage filtration, it enters into the crystallization tank for crystallization. Adopt the way of lead crystal and control cooling to achieve the control of crystal size distribution. After the feeding of crystallization tank is finished, began to control the cooling speed for cooling, when the material cooling to the crystal point, add an appropriate amount of crystal seed. When reduce the low temp., add the antifreeze solvent, cooling to 0℃ below to discharge. Adopt the centrifuge system for the solid-liquid separation and remove the washing liquid of the mother liquid. The wet vitamin C is dried through the dryer. The drying temp. is controlled to be less than 65℃. Drying time ≤ 3 hours. After drying, the material is cooled and discharged. During the drying process, the dryer adopts the pressure reduction method to protect the material. After drying, the material is through screening and gold inspection. When the inspection is qualified, after weighing and packaging, then for storage.

The separated mother liquor is dealcoholized and then processed in the desalting process of conversion section. The separated crude methanol is rectifying in the distillation column and reused in the refinery section.