Hydrothermal carbonization of off-specification compost: A byproduct of the organic municipal solid waste treatment

Abstract

The possibility to apply the hydrothermal carbonization (HTC) process to off-specification compost (EWC 19.05.03) at present landfilled was investigated in this work. The aim was to produce a carbonaceous solid fuel for energy valorization, with the perspective of using HTC as a complementary technology to common organic waste treatments. Thus, samples of EWC 19.05.03 produced by a composting plant were processed through HTC in a batch reactor. Analytical activities allowed to characterize the HTC products and their yields. The hydrochar was characterized in terms of heating value, thermal stability and C, H, O, N, S and ash content. The liquid phase was characterized in terms of total organic carbon and mineral content. The composition of the gas phase was measured. Results show that the produced hydrochar has a great potentiality for use as solid fuel.

Hydrothermal Carbonization of Waste Biomass: Process Design, Modeling, Energy Efficiency and Cost Analysis

“…Although it is often used for the production of spirits through distillation, it is still found as lignocellulosic residue at the end of this process (exhausted GM). Our experimental measures revealed moisture content of about 30% for OSC [17] and 65% for GM [21].…”

“…The total organic content (TOC) of the liquid phase from HTC was used to compute the amount of phenol as the representative species of the organic liquids. HTC lab tests performed on OSC [17] show that TOC values increase at increasing temperature: Figure 1d. Time plays a marginal role, such that only temperature dependence was taken into account.…”

“…The types of feedstock used in the experiments were "off-specification compost" (OSC), coded by the European Waste Catalogue as EWC 19.05.03 [17], and grape marc (GM) [18]. OSC is a bio-stabilized material that is discarded and landfilled following the composting process because of its large particle size (between 10 and 40 mm).…”

“…The process model, developed to simulate a continuous HTC plant with all the auxiliary equipment (see Section 2.2), uses HTC experimental data previously obtained by our research group [17,18]. Experiments were performed in a stainless steel batch reactor, with an internal volume of 50 mL.…”

The influence of composts on potato tuber, spring oilseed rape seed and threshing residue yields and concentrations of chemical elements in them

“…Nowadays, the organic waste utilisation involves technologies such as composting or anaerobic digestion that result in the degradation and stabilisation of organic matter and mass and volume reduction (Basso et al, 2015). However, composting is at the moment the most widely used technology for the stabilisation of organic wastes due to the complexity and economic investment that anaerobic digestion requires (Cadena et al, 2009).…”