Analysis of Manure Separation Technology Efficiency into Fractions Followed by Liquid Fraction Rectification

Abstract

Introduction. There is not enough data on the used intensive technologies of processing pig manure into organic fertilizer to accurately calculate the content of nutrients in the final products and, accordingly, their doses of application. Aim of the Article. To determine the efficiency of pig manure processing technology, which includes liquid fraction rectification, by the quantitative and qualitative characteristics of manure and final products, and to trace the redistributing total nitrogen between the final products on the example of a pilot pig breeding complex production. Materials and Methods. For the study, there was chosen a typical pig-breeding complex, where the pig manure processing included slurry acidification, flocculation, separation into fractions in a decanter centrifuge, rectification of liquid fraction, passive composting of solid fraction, and long-term storing of liquid fraction. The technology allows producing three types of end products: solid organic fertilizer, concentrated liquid (ammonia water), and fertilizer solution. Quantity and quality of pig manure and the end products were calculated by the known methods. Experimental studies were performed to compare the results. Samples were analyzed in the analytical laboratory of Institute for Engineering and Environmental Problems in Agricultural Production in 2022. Three replications were carried out for each sample. The experimental data were statistically analysed in MS Excel. Results. Quantitative and qualitative characteristics of pig manure, its solid and liquid fractions, and end products were calculated. The difference between the calculated and actual values does not exceed 10.2% that indicates the reliability of calculations. Discussion and Conclusion. The introduction of a new technology at the pig-breeding complex has reduced atmospheric emissions by 10% due to the nitrogen conservation, has reduced operating costs for transporting organic fertilizer by 47% due to the concentration of nutrients in a smaller volume and has improved soil fertility through fertilizer irrigation.