The diagram is an illustration of the key steps required for the processing of corn, a grain, into ethanol, an alcohol by-product that has many industrial uses.
Once an adequate quantity of corn has been procured or harvested, it must be stored and then milled. Following the milling step, the corn is cooked in water for 4 hours. This is followed by the fermentation step. This step takes 2 days and is the longest step in the process.
Once fermentation is complete and the liquid is separated from the solid by-product, we can now move onto purification. This is a faster process, by contrast, requiring a mere 5 hours and the resulting product is pure ethanol. The ethanol can now be stored appropriately and transported. Thus all-in-all, this method of ethanol fuel production involves five key steps and takes approximately 3 days.