A Review on Pilot-Scale Applications of Hydrothermal Treatment for Upgrading Waste Materials

Abstract

Abstract-In this paper, a review on applications of hydrothermal treatment (HTT) for upgrading waste materials was presented. This work was focused on pilot-scale HTT processes that applied to several kinds of waste for alternative solid biofuel production. The HTT utilizes subcritical water condition that has special properties as an organic solvent. With the temperature around 180-240 °C and the corresponding pressure that keeps the water in the liquid phase, many reactions are induced by the subcritical water such as hydrolysis and dehydration. The waste materials that had been subjected to the HTT processes by pilot-scale reactors such as paper sludge, antibiotic residue, and municipal solid waste were reviewed herein. Moreover, a novel application of HTT on hospital waste treatment has been carried out in a pilot-scale level. Results showed positive effects and consistency with the previous research works. Thus, the HTT showed possibility to be an option for pretreating waste materials prior to final conversion processes.Index Terms-Hydrothermal treatment, high moisture waste, pilot-scale hydrothermal, solid biofuel.

Chemical structure analysis and fast micro-pyrolysis study of hydrochar derived from hydrothermal treatment of municipal solid waste

“…Municipal solid waste (MSW) treatment has always been a serious environmental and social issue in developing countries. The wide diversifications in the moisture content, physical shape, chemical compositions and energy densities of MSW result in inefficient handling, transportation and storage, which has greatly limited its application via thermal utilization (Areeprasert et al, 2016; Hu et al, 2015; Lu et al, 2011). To overcome these limitations, pre-treatment of MSW is a necessary step before it is utilized as an efficient energy resource (Li et al, 2013; Prawisudha et al, 2012).…”

“…To overcome these limitations, pre-treatment of MSW is a necessary step before it is utilized as an efficient energy resource (Li et al, 2013; Prawisudha et al, 2012). Among pre-treatment technologies, hydrothermal treatment (HTT) has gained extensive attention and has been widely used in treating high moist biomass with safe disposal and energy recycling (Areeprasert et al, 2016; Gao et al, 2016; Zhao et al, 2014).…”

“…HTT, also referred to as wet torrefaction or hydrothermal carbonization (HTC), is a thermochemical process of converting organic feedstock into value-added solid fuels (Areeprasert et al, 2016; Kambo & Dutta, 2015) without an energy extensive drying process (Gao et al, 2016; Guo et al, 2015). In recent years, the HTT technology has been applied to paper sludge and six typical components of MSW by researchers (Lin et al, 2015, 2016a, 2017a, 2017b).…”

Hydrothermal Carbonization of Various Paper Mill Sludges: An Observation of Solid Fuel Properties

“…For instance, Areeprasert et al performed HTC of PSS in a batch reactor at 180-240 • C for 30 min to determine optimal HTC conditions [40][41][42]. Afterwards, HTC was performed at the optimized condition (197 • C and 30 min) in a small pilot scale [43]. Their results indicate that HTC of PSS is energetically favorable in the context of Japan.…”