To O2, Or Not To O2…
Composting is the process of decomposing organic material, like food scraps, into a nutrient-rich soil amendment in the presence of oxygen (O2). Anaerobic fermentation uses bacteria to break down organic material when there is no oxygen (O2) present.
As a way to lessen the negative environmental effects of uneaten food, there has been an increase in interest in local or on-site aerobic composting in recent years, for which in-vessel rotary drum composting is the ideal method. In order to guarantee proper aeration and mixing, this technique entails adding organic material to a digestion vessel that is aerated and rotated.
Aerobic in-vessel rotary drum composting is more ecologically responsible than anaerobic fermentation for a number of reasons. There are no greenhouse gas emissions from aerobic composting. Methane is a product of the oxygen-free breakdown of organic material. Methane is a powerful greenhouse gas that contributes significantly to global warming. It is many times more powerful than carbon dioxide. Two molecules of water vapor, the most powerful greenhouse gas, and one molecule of carbon dioxide, another very potent greenhouse gas, are released when methane is burned to produce electricity.
Compared to anaerobic fermentation, aerobic composting is more effective at degrading organic material. Together, microorganisms in an aerobic composting system break down complicated organic substances into smaller molecules that plants can use as nutrients. Anaerobic fermentation, which depends on a small number of microbes to break down organic matter, involves a much slower process.
Also, aerobic composting yields compost while anaerobic fermentation yields a digestate and not compost. Because of its abundant nutrient content and helpful microorganism activity, aerobic composting produces compost that is a superior soil amendment. Contrarily, anaerobic fermentation can result in the production of digestate that may be highly pathogenic and unfit for use in food production. Aerobic composting produces little-to-no odor as compared to anaerobic methods, making it a more appealing option for on-site composting in residential areas or urban environments.
Lastly, aerobic composting technologies are more adaptable and scalable than those of anaerobic composting facilities. Depending on the volume of organic waste produced, an aerobic in-vessel rotary drum composting system can be scaled up or down, making it a viable choice for both small-scale residential composting and large-scale commercial composting. Anaerobic fermentation, on the other hand, necessitates specialized infrastructure and machinery, making it less practical for smaller-scale composting operations.
