only the biomass components from the MSW or other sources that are not having the
potential of causing issues in the food cycle.
4 Advanced Thermal Treatment (Hydrothermal Treatment
of Municipal Solid Wastes)
Hydrothermal technology is specifically targeted technology for the treatment of
organic wastes in both wet and dry forms, as well as the destruction of hazardous and
chemical wastes. The use of hydrothermal technology in the treatment of biodegradable wastes in the MSW is increasing in global literature because it is believed to
serve as a reliable solution to the issues related to fossil fuels and their emissions.
This technology is believed to be the everlasting solution to the ever-increasing
biodegradable wastes in the MSW stream across the globe. The technology is tested
and proven to be an alternative solution in tackling the energy shortage and environmental pollution, as well as a potential alternative source of green fuels [32, 33].
4.1 Hydrothermal Technology
The term ‘hydrothermal’ is used to refer to any heterogeneous reaction in the
manifestation of aqueous solvents or mineralisers, under conditions of high temperature and pressure, to dissolve and recrystallise materials that are relatively insoluble
at normal conditions. Hydrothermal technology got its first successful commercial
application in the extraction of ores in the twentieth century. In this century,
hydrothermal technology has found many applications in the branches of science
and technology in the production of environmentally safe and green energy, especially in waste biomass treatment [34, 35].
The application of hydrothermal technology in MSW treatment is aimed at
solving the problem of organic wastes, which has the highest proportion in the
MSW. However, the technology can also be used in the treatment of hazardous
wastes, wastes with higher water contents, halogenated wastes and chemical wastes.
The various chemistries involved in the treatment of organics using hydrothermal
technology are highlighted in Fig. 9.
The hydrothermal technique has become the most popular, garnering interest
from scientists and technologists of different disciplines, particularly in the last
15 years. It is worth noting that, despite the fact that this technology has made
tremendous progress in all angles of science and technology, there is no unanimity
about its definition. As shown in the figure, the hydrothermal technology involves
subjecting the organic components of the MSW to the action of water at higher
temperature considered as above critical temperature (370
C), and higher pressure is
referred to as supercritical [34].
190
A. A. Gado et al.
potential of causing issues in the food cycle.
4 Advanced Thermal Treatment (Hydrothermal Treatment
of Municipal Solid Wastes)
Hydrothermal technology is specifically targeted technology for the treatment of
organic wastes in both wet and dry forms, as well as the destruction of hazardous and
chemical wastes. The use of hydrothermal technology in the treatment of biodegradable wastes in the MSW is increasing in global literature because it is believed to
serve as a reliable solution to the issues related to fossil fuels and their emissions.
This technology is believed to be the everlasting solution to the ever-increasing
biodegradable wastes in the MSW stream across the globe. The technology is tested
and proven to be an alternative solution in tackling the energy shortage and environmental pollution, as well as a potential alternative source of green fuels [32, 33].
4.1 Hydrothermal Technology
The term ‘hydrothermal’ is used to refer to any heterogeneous reaction in the
manifestation of aqueous solvents or mineralisers, under conditions of high temperature and pressure, to dissolve and recrystallise materials that are relatively insoluble
at normal conditions. Hydrothermal technology got its first successful commercial
application in the extraction of ores in the twentieth century. In this century,
hydrothermal technology has found many applications in the branches of science
and technology in the production of environmentally safe and green energy, especially in waste biomass treatment [34, 35].
The application of hydrothermal technology in MSW treatment is aimed at
solving the problem of organic wastes, which has the highest proportion in the
MSW. However, the technology can also be used in the treatment of hazardous
wastes, wastes with higher water contents, halogenated wastes and chemical wastes.
The various chemistries involved in the treatment of organics using hydrothermal
technology are highlighted in Fig. 9.
The hydrothermal technique has become the most popular, garnering interest
from scientists and technologists of different disciplines, particularly in the last
15 years. It is worth noting that, despite the fact that this technology has made
tremendous progress in all angles of science and technology, there is no unanimity
about its definition. As shown in the figure, the hydrothermal technology involves
subjecting the organic components of the MSW to the action of water at higher
temperature considered as above critical temperature (370
C), and higher pressure is
referred to as supercritical [34].
190
A. A. Gado et al.