Marketable fertilizer may be formulated from chicken manure, solid digestate or pig slurry after mechanical separation. Using the above three basic substrates with biochar and vermiculite additives to improve fertilizer properties and reduce odors, we make pelletized organic fertilizers. The best properties were obtained with a mixture of chicken manure and separated pig slurry. We found that the input pelletizing substrates were too moist and would need to be pre-dried. Based on the model scenario, we proved that separation is an efficient process by which 25-35 % N, 55-65 % P and 20-30 % K pass into the solid part, and a nutrient-rich marketable organic fertilizer can be made. By selling such fertilizer the excess off nutrients would be removed from an intensive pig farm. As a result, less fertilizing areas around a farm are needed, transport costs are reduced and the environment is protected at the same time. Due to high content of plant nutrients, especially phosphate, the dosages of such fertilizer may be relatively small, averaging up to 2.5 t/ha annually, so despite the high organic matter content (20 % C), such fertilizer is not a significant soil humus producer.
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