International Science and Technology Journal

Citric acid is a naturally occurring organic acid, it is found in citrus and is a natural organic preservative, it is known as lemon acid, it is called in popular circles and consumer markets with food salt, which is a transparent crystals tend to light white, and its scientific names are hydrogen citrate, where are part of it consists of six carbon atoms and seven oxygen atoms and eight hydrogen atoms, it is chemical compound and it has a high circularity in water. Chemical reactors are the space where interaction in limited and converting the reactive materials into products, it is reported that, the reactor in the images more complex as in laboratories and medical laboratories, Such as laboratories and booths in which various chemical processes and carried out. The complexity of looking at large nuclear reactors, for example, and the medicine in which the drugs are produced and as bioreactors, which are the main heart of biochemical technologies. In this paper, the mechanical mixing speed of STR reactor was studied and their effect on fermentation processes, biomass growth and the amount of citric acid production. Our study and results showed that the high speed of mixing in stirred tank reactor is effect on the fermentation process and production of citric acid.