Submitted to: Book Chapter
Publication Type: Book / chapter
Publication Acceptance Date: 1/20/2013
Publication Date: 7/29/2013
Citation: Berge, N.D., Kamman, C., Ro, K.S., Libra, J. 2013. Environmental applications of hydrothermal carbonization technology: Biochar production, carbon sequestration, and waste conversion. p. 295-340. In: Titirici, M.M. ed., Sustainable Carbon materials from Hydrothermal Processes. Wiley, West Sussex, UK. Interpretive Summary: Utilization of hydrothermal carbonization (or wet pyrolysis) in environmentally-relevant applications is fairly new and there is much additional research required to fully explore the potential and subsequent use of the process in such applications. This chapter describes the current knowledge associated with environmentally-related hydrothermal carbonization applications. The use of hydrothermally carbonized materials, or hydrochar, as a soil amendment may increase the carbon content of degraded soils and ultimately improving soil fertility; however, more scientific information is needed. The technique can also be used as a waste management tool. Waste streams, such as municipal solid waste, animal wastes, and human wastes, may be sustainably converted to a stable, sterile, carbon-rich, high energy-density hydrochar using this technique while sterilizing the waste streams with high temperature and pressure used in the process. The waste-derived hydrochar can be used as a soil amendment to build up soil quality and environmental adsorbent to remove contaminants in the air, water, and soil. Fugitive greenhouse gas emissions from landfills and livestock facilities may be reduced by incorporating the hydrothermal conversion technology.
Technical Abstract: Motivations for the development and use of hydrothermal carbonization (or wet pyrolysis) have been primarily directed towards the sustainable creation of carbon nanomaterials/nanostructures for use in applications ranging from hydrogen storage to chemical adsorption. The utility of this process, however, has recently evolved to include investigation of biomass and waste stream carbonization for environmental benefit. The carbon-rich material, often referred to as hydrochar, resulting from the carbonization of these feedstocks may be used in a variety of environmental applications, such as a soil amendment and as an adsorbent in environmental remediation processes. Hydrothermal carbonization has also shown promise as a sustainable waste stream conversion technique, ultimately converting waste materials to value-added products, while promoting integration of carbon in the solid-phase. Waste streams, such as municipal solid waste, animal wastes and human wastes, may be sustainably converted to a stable, sterile, carbon-rich, high energy-density hydrochar via hydrothermal carbonization. The hydrochar may serve as a source of renewable solid fuel as a green coal. In addition, land application of hydrochar, particularly when rich in carboxyl groups, may increase the carbon content of degraded soils and ultimately improving soil fertility. However, the information regarding the application of hydrochar in soils is still in its infancy. Utilization of hydrothermal carbonization as a conversion technique may reduce fugitive greenhouse gas emissions from municipal solid waste landfills and livestock facilities.