The provided diagram encapsulates the overall cyclic steps involved in the manufacturing process of ethanol.
Viewing from a broader perspective, it is evident that the entire process involves three main stages: harvesting, processing, and pre-processing to extract sugar out of cellulose, followed by microbial addition to form the final product.
At first, the energy in the form of sunlight and carbon dioxide is harvested from tree and other plantations. This harvest is then sent to the mills , where they use various modern machinery to extract cellulose out of the harvest.
This extracted cellulose is then sent to labs for processing where certain specific chemical reactions are used for the extraction of sugar out of cellulose. Once the sugars are formed , microbes are added to the sugar which breaks it down to ethanol using anaerobic respiration to form the end-product called Ethanol.
This Ethanol is then supplied as fuel for various kinds of vehicles like cars, buses and airplanes which ignites the fuel to release carbon dioxide into the atmosphere. The carbon dioxide released into the atmosphere along with sunlight is then utilized by plantations for the formation of energy. This process continues to complete the cycle.