Citric Acid

Citric acid is mainly used in the food and beverage industry as an acid flavoring agent, seasoning agent, and preservatives. It is also used as an antioxidant, plasticizer, detergent, in the chemical industry, cosmetics industry, and laundry industry.

Around 2.5 Million tons of citric acid was consumed world wide every year.

Process Flow

Process Description.

1 Raw material pretreatment

After the corn was crushed, the slurry was heated, and the sugar liquid was filtered by enzyme liquefaction.

2 Fermentation

The sugar solution is pumped into the cleaned fermenter, after steam heating and disinfection, adjust the temperature of fermentor, then the cultivated seeds will be transferred from baby fermentor to production fermentor.

3 Broth filtration

After fermentation is completed, the fermentation broth will be heated and sterilized. The mycelium in the fermentation solution was separated and the fermentation liquid was collected and to be used in the purification workshop.

4 Mycelium drying

Mycelium residues are collected by screw conveyors and belt conveyors, dried by tube bundle dryers to remove excess water and obtain high-quality protein feed.

5 Neutralization

The neutralization section uses the reaction of citric acid and calcium carbonate in the fermentation liquid clear liquid, by controlling appropriate temperature, PH, and reaction speed, we can get qualified calcium citrate and calcium hydrogen citrate in turn.


The decomposition section uses sulfuric acid and calcium hydrogen citrate to react in order to obtain citric acid and gypsum residue.

Decolorization and Ion Exchange

Decolorization is the use of activated carbon to adsorb colorants, GAC carbon column is typically used in this process.

Concentration and crystallization (anhydrous citric acid crystals)

The multi-effect concentration evaporator is used to increase the liquid concentration. After reaching the required concentration, the Citric acid is continuously crystallized under the action of the forced circulation pump (the crystallization at this time is anhydrous citric acid crystal).

CAA centrifuge and drying

The wet crystal in the crystal slurry tank is put into the centrifuge to obtain the wet crystal with qualified moisture, and then the wet crystal is transported to the dryer for drying.

CAM crystallization

The mother liquor produced during the separation of anhydrous citric acid is pumped into a colling crystallization tank, by controlling the proper temperature, Citric monohydrate can be crystalllized.

CAM centrifuge and drying

The free water attached to the surface of CAM is vaporized and taken away by hot air through a vibrating fluidized bed to remove moisture.

Screening and Package

The dried anhydrous citric acid and citric acid monohydrate entered into the screening machine, then to be packaged according different specification.