Effect of biochars produced from solid organic municipal waste on soil quality parameters. (1st May 2017)

• Record Type: Journal Article
• Authors: Randolph, P.; Bansode, R.R.; Hassan, O.A.; Rehrah, Dj.; Ravella, R.; Reddy, M.R.; Watts, D.W.; Novak, J.M.; Ahmedna, M.
• Is Part Of: Journal of environmental management. Volume 192(2017)
• Page Start: 271
• Page End: 280
• Publication Date: 2017-05-01
• Subjects: Biochar -- Soil amendment -- Carbon sequestration -- Environment -- Sustainability; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2017.01.061
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: New value-added uses for solid municipal waste are needed for environmental and economic sustainability. Fortunately, value-added biochars can be produced from mixed solid waste, thereby addressing solid waste management issues, and enabling long-term carbon sequestration. We hypothesize that soil deficiencies can be remedied by the application of municipal waste-based biochars. Select municipal organic wastes (newspaper, cardboard, woodchips and landscaping residues) individually or in a 25% blend of all four waste streams were used as feedstocks of biochars. Three sets of pyrolysis temperatures (350, 500, and 750 °C) and 3 sets of pyrolysis residence time (2, 4 and 6 h) were used for biochar preparation. The biochar yield was in the range of 21–62% across all feedstocks and pyrolysis conditions. We observed variations in key biochar properties such as pH, electrical conductivity, bulk density and surface area depending on the feedstocks and production conditions. Biochar increased soil pH and improved its electrical conductivity, aggregate stability, water retention and micronutrient contents. Similarly, leachate from the soil amended with biochar showed increased pH and electrical conductivity. Some elements such as Ca and Mg decreased while NO3 -N increased in the leachates of soils incubated with biochars. Overall, solid waste-based biochar produced significant improvements to soil fertility parameters indicating that solid municipal wastes hold promising potential as feedstocks for manufacturing value-added biochars with varied physicochemical characteristics, allowing them to not only serve the needs for solid waste management and greenhouse gas mitigation, but also as a resource for improving the quality of depleted soils. Highlights: Paper and wood waste can serve as feedstocks for the production of value-added biochars. Biochars can alleviate economic and environmental problems associated with solid waste disposal. Soils amended with solid organic waste derived biochars can improve soil in fertility. Biochars prepared from solid municipal waste can also be used for soil-carbon sequestration.