background

Fermented Fertilizer

Fermented Fertilizer
WHAT ARE THE FEATURES OF SOLID AND LIQUID FERTILIZERS PRODUCED IN BIOGAS PLANTS?

ARF Ödemiş Biogas Plant protects the environment by generating energy from plant wastes of organic origin and dairy cattle manure and adds life to soil with fertilizers produced therefrom.

  • The byproduct of anaerobic fermentation is FERMENTED FERTILIZER.
  • FERMENTED FERTILIZER is a primary byproduct of biogas plants.
  • Fertilizer from biogas plants are fermented byproducts obtained in anaerobic environment, and hence, are free of substances harmful to plants or the environment, making it an excellent option for agricultural use.
  • Biogas technology protects the environment by generating energy from wastes / residues of organic origin and adds life to soil with fertilizers produced therefrom.
  • When animal manure is temporarily stored without stabilization, the nitrogen compounds in the manure decompose under uncontrolled conditions, resulting in a loss of about 50 - 70%.
  • This means a significant loss of nutrients.


The elements, which make up about 70% of the solid matter used in feed, remain unchanged in quantity and structure after fermentation, depending on the substances they contain.

The carbon, oxygen and hydrogen present in feed decompose during anaerobic fermentation, creating methane and carbon dioxide.

The other nutrients and elements are preserved.

Unlike fresh manure, fermented manure contains nitrogen, potassium and phosphorus in a form that can be readily used by plants.

  • Fertilizer (fermented manure) from biogas plants is in liquid form.
  • If this fermented byproduct is passed through a separator, fibrous solid fertilizer and liquid fertilizer are obtained.
  • Solid fertilizer is used instead of turf in soil conditioning; and liquid fertilizer is used instead of inorganic fertilizers.


Research in China has shown that the amount of nutrients in soil increased by 6-10%, and in long-term experiments, the physical and chemical properties of the soil improved significantly.

In another study, use of fermented fertilizer for more than one year resulted in a continuous increase in grain production.

This increase exceeded 20% with the elimination of phosphorus deficiency in fermented fertilizer.

Fermented fertilizer contains essential plant nutrients along with other essential elements like calcium, sulfur, magnesium, copper, zinc, and manganese.

  • As fermented fertilizer is in liquid form, it can be easily pumped to remote areas without clogging the pipes.
  • Fermented fertilizer with a high water concentration can be applied to agricultural land by conventional irrigation methods.


In a study in southern Germany, all farmers who used fermented fertilizer reported that it was easier to use and produced less odor, and 81% reported higher grain yields.

Examples of fermented fertilizer application by means of sprinklers are as follows:

Fermented fertilizer is more effective when used before planting and when it is injected into the soil and then covered with soil.

  • When anaerobically digested liquid fertilizer is applied into the soil at a certain depth, it becomes possible for plants to fully utilize nitrogenous substances as nutrients.
  • This can be done by injection or with furrowing tools.


Fermented fertilizer;
  • Improves the physical properties and water-holding capacity of the soil,
  • Aerates the soil,
  • Increases pH buffering capacity,
  • Bonds with inorganic soil elements and thus prevents percolation loss,
  • Prevents soil erosion,
  • Helps prevent odor and fly growth, and
  • Deactivates weed seeds.
  • Fermented fertilizer is advantageous not only because it is nutritious but also because it prevents erosion thanks to its fibrous content.
  • Thus, it mitigates the loss of humus, i.e., the dark organic matter in topsoil that keeps the soil together, protects the soil from wind and rain damage, has a determining effect on soil fertility, and at the same time, increases the water-holding capacity of the soil.
  • The nutrients in fermented fertilizer enable bacteria growth in the soil and thus promote soil improvement.
  • In a study conducted in 1988, fermented fertilizer was used in a fish pond and the outcome was very favorable.
  • After fermented fertilizer was added to the pond, more dissolved oxygen was measured, the temperature of the water increased, thus contributing to the growth of fish, and there was a decrease in fish diseases as the fermentation killed unwanted bacteria and parasite eggs.