Digestate, a fertilizer

Sixth Official Post

The last product which Anaerobic Digestion produces is the digestate. The microbes cannot feed on everything and the solid remnant of the initial waste material will be called the digestate. It can be fibrous or liquor.

Acidogenic digestate is a material which consists mainly of lignin and cellulose. Low grade building products like fibreboard can be made from it.


Methanogenic digestate is rich in nutrients making it suitable to be used as a fertilizer. However, if the quality of the initial material is low, the levels of potentially toxic elements (PTEs) will be higher. This will make it not suitable to be a fertilizer and the use of it will be dependent on its levels of PTEs.

Lignins which anaerobic microorganisms cannot break down will be present in the digestate. Furthermore, ammonia which will disrupt plant’s growth will be present as well. Aerobic microorganisms will then be introduced to break down ammonia into nitrates, which increase the fertility of the material. Then, it will improve the quality of soil more efficiently.

Anaerobic Digestion provides an alternative for fertilizer. Fertilizers are extremely important in the growing of plants and crops. It can be used to improve the health and productivity of crops. In some countries where a lot of their soil is infertile, they can use fertilizer to be able to grow crops there. Instead of producing fertilizer industrially, Anaerobic Digestion can produce fertilizer while producing biogas. Wouldn’t that be nice?