Biogas plants are producing a methane rich gas and an organic bio-rest which is considered as waste or a soil improver. The nitrogen in the bio-rest is easily lost as volatile ammonia. The nutrient value of the bio rest can be significantly upgraded by treating the bio-rest with acidic nitrate and nitrite. The nitrogen content and nitrogen value can easily be doubled giving a bio-rest with a value as balanced organic fertilizer.

Biogas plant

Biogas plant
Effluent = bio-rest can be upgraded with nitrates

Organic waste is a resource for energy and nutrients. In a biogas plant, the energy from carbohydrates is converted to a gas mixture of methane and carbon dioxide. The biogas can be further purified to methane which is as a high value energy source for gas driven cars or busses.

The organic waste being fed to a biogas plant contains valuable nutrients like phosphate, potassium and nitrogen. The phosphate and potassium is contained in the solid part of the organic material. The nitrogen is initially contained in proteins and urine, but through the biological conversion to methane, the organic nitrogen is converted to ammonia.

The ammonia is alkaline and is driving the pH up to critical levels for the biogas process.  In the bio-rest, the ammonia is easily lost, when exposed to atmospheric conditions. The bio-rest is therefore low in nitrogen, and is not giving a balanced and effective nutrient mix to the plants, when applied as organic fertilizer.

The N-fix technology is applying a tailored mix of acidic nitrates and nitrides. The acidic nitrates and nitrides will bind the ammonia in the form of readily available ammonium salts in the bio-rest.  The concentration of nitrate and nitrite in combination with the right the pH, is required to minimize the nitrification and de-nitrification leading to N-losses.

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