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iopscience.iop.org/article/10.10...7/1/012007/pdf

M Kusuma and R Afrianisa 2021 J. Phys.: Conf. Ser. 2117 012007DOI 10.1088/1742-6596/2117/1/012007

The demand for organic fertilizers in Indonesia is currently in a critical state. In 2015, it was noticed that the demand of Indonesia for NPK fertilizers reached over 6.5 million tons per year. Given the current state of demand for organic fertilizers in Indonesia, it is imperative to have alternative organic fertilizers that are environmentally friendly and readily available raw materials. One alternative is to use biogas waste that contains essential plant-based nutrients such as NPK (nitrogen, phosphorus, potassium) and additional nutrients such as magnesium (Mg), calcium (Ca) and sulfur (S). The composition of Bio-Slurry after fermentation consists of 25% ± 5 dry matter and 75% ± 5 water. If the dry substance is decomposed, it contains 18- 27% organic matter. The production of liquid organic fertilizers from BioSlurry requires some anaerobic fermentation process lasting 20 days. During the fermentation process it is necessary to additional raw materials such as cow urine, banana stalk and banana peel to add the N, P and K values to BioSlurry. In the initial characterization test, BioSlurry liquid (after pressing) showed an NPK value of <1% and a C-Organic value of 0.04.