Technology for Producing Bioethanol from Grain

Grain is received by rail or truck and unloaded into silos designed for three days of storage. As needed, the grain is fed into the receiving hopper, weighed, and then transported via a screw conveyor and bucket elevator to the cleaning section.

Grain from the storage silo is fed into the cleaning section, where foreign matter and other impurities are removed. The cleaned grain is ground into flour using crushers.

Grain flour is weighed out in the required proportion and mixed with fresh and lye water to form a suspension. The suspension is transferred to a container, and enzymes are added to reduce its viscosity.

Under the influence of steam, the starch is broken down and liquefied by enzymes. The mixture prepared in this way is heated to 90°C, and enzymes are added to convert the starch into sugar. The saccharified mixture is cooled to a temperature of …

The sweet mash is divided into the main mash and the yeast mash. Yeast cultures are added to the yeast mash, and the yeast is grown there to facilitate the fermentation of the main mash.

Перетворення основного Сусла за допомогою дріжжів у спиртову бражку 10-12% Еt з виделенням СО2. Процес проходить при постійному перемішування з підтриманням постійної температури 34-36

°С протягом 24-48 годин.

Carbon dioxide is removed using alcohol scrubbers and sent for compression. The compressed 99.9% CO₂ is cooled, purified, and filled into cylinders.

In the distillation and rectification columns, 92–95% raw alcohol is separated from the alcoholic mash using steam. The rectification process also yields distiller’s grains, still water, and fusel oil.

The final step in the production of bioethanol is the removal of water from 92–95% raw alcohol through adsorption on molecular sieves, which yields a 99.8% Et solution. By denaturing the 99.8% alcohol, we obtain bioethanol. The bioethanol is stored in tanks.

From the distiller’s grains, a cake with a dry matter content of 30–35% and a distiller’s grains decanter with a dry matter content of 4–8% are separated.

The vacuum evaporation unit removes moisture from the distiller’s grains decant to a dry matter content of 30%. The decant can then be further dried to a dry matter content of 75%.

From the distillers’ cake with 30–35% moisture content, the remaining moisture is evaporated in a drum dryer until the moisture content reaches 10%???. The dry cake is granulated and becomes DDGS—an animal feed with a protein content of up to 40%.