Evaluation of the Use of Organic Waste Generated at Hydroelectric Power Plants in the Production of Organic Fertilizers

• Published in: Waste and biomass valorization 2020-09, Vol.11 (9), p.5041-5051
• Main Authors: Martins, Deise Soares, Shinzato, Mirian Chieko, de Moraes, José Ermírio Ferreira
• Format: Article
• Language: English
• Subjects: Carcasses; Composting; Composts; Electric power generation; Engineering; Environment; Environmental Engineering/Biotechnology; Evaluation; Fertilizers; Grasses; Humus; Hydroelectric plants; Hydroelectric power; Industrial Pollution Prevention; Legislation; Manures; Organic wastes; Original Paper; Power plants; Renewable and Green Energy; Seedlings; Seeds; Vegetables; Waste Management/Waste Technology; Water hyacinths
• ISSN: 1877-2641; 1877-265X
• DOI: 10.1007/s12649-019-00790-y

This work evaluated the composting process of different organic wastes produced in a Brazilian hydropower plant (HPP). The experiments were carried out in a composting unit using an initial volumetric proportion of 30 parts of dry grass clippings to one part of other organic wastes (water hyacinth, seeds, manure and carcasses of fish and bird). The efficiency in composting 100% grass clippings was also evaluated. After 90 days the composting end products were examined to verify their quality and maturity. During the composting process the tests performed with vegetable wastes and manure presented higher temperature (around 63 °C) in the thermophilic phase than those prepared with animal carcasses (56 °C for Fish and 46 °C for Birds) and 100% grass (57 °C). Vegetable wastes and manure experiments stabilized earlier (after 40–45 day) than the other tests (after 60 days). The pH values of composts prepared with vegetable wastes and manure were higher (around 7) than those prepared with animal carcasses (around 5). These results indicate the need to increase the initial proportion of nitrogen in composting tests using animal carcasses and 100% grass to improve the maturity rate and raise the temperature of thermophilic phase. However, the final composts presented most of chemical and physicochemical parameters within or close to the levels established by the Brazilian legislation for fertilizers produced through composting. About 3 m 3 of humus were produced from composting 20 m 3 of organic wastes, which can be used in the projects that develop seedlings nurseries of native plants in the HPP area. Graphic Abstract Evaluation of the use of organic waste generated at hydroelectric power plants in the production of organic fertilizers