Process development for selective removal of nutrients from liquid manure

The agricultural sector likes to contribute to the societal challenges of limiting nitrogen and (climate driven) CO2 emissions into the atmosphere. In addition, the agricultural sector wishes to valorize its liquid manure streams by producing high concentrated mineral concentrates next to high concentrated nitrogen (N) and potassium (K) fractions. The separate fractions are useful to adapt to the needs of a specific crop and tailored to the time of the year and thereby increasing the circularity of our food chain. Analysis has shown that a restriction in liquid manure utilization lies in the nitrogen and potassium balance, as this ratio does not meet the requirements for optimal plant growth which limits the use of animal manure mineral concentrates. Therefore high precision fertilizing requires concentrating and separation of the nutrients present in liquid manure streams such that these become available as individual fractions that can be mixed in the crop specific optimal ratios.

In order to valorize the manure into valuable fertilizers, two approaches will be investigated. The first one is the optimization of the pre-treatment and reverse osmosis steps of the currently used manure treatment processes to find opportunities that result in more easy to handle mineral streams with higher nutrient loads. The second approach focusses on the production of N and K rich fractions, so that precision farming with (exclusively) animal fertilizers can be applied, which also contributes to the emission targets.