which includes composting, anaerobic digestion and refuse-derived fuel (RDF). The
glasses and plastic components are separated for recycling and reuse as aggregates,
while the metals are extracted for recycling. The water used in the system is usually
trapped and recycled in the process, and the final wastewater is discharged as an
effluent stream which removes pollutants from the process. The great advantages of
this technology are its ability on the treatment of all form of wastes in the MSW
stream, including those that are not recyclables like metals. The technology also
enables the reuse option for plastics, as well as sterilising plastic wastes before the
recycling. The metals and plastic wastes treated using this technology are always
comparable to virgin materials. The autoclaving plants are modular in nature because
they are made up of units which can be added or taken away based on changes of the
waste stream or volume of the wastes. Huge development is witnessed in using the
cellulosic pulps from the treated wastes using this technology in biofuel production.
3.3 Microwave Technology
Microwave technology is becoming widely used in the globe, in the treatment and
remediation of environmental problems related to municipal solid waste. Since the
first use of this technology in the 1940s by Percy Spencer, microwave heating is
constantly getting serious attention by different researchers across the globe
[26, 27]. In recent years, microwave technology is proven to be an attractive
technology for the treatment of municipal solid wastes in addition to many astonishing applications in different areas of human life. Microwave technology operates
by delivering direct energy to the microwave absorbing material for complete
heating of the material from the outside and inside as shown in Fig. 7. Microwave
operates in the region between the electromagnetic spectrum and infrared radiation
region. Microwaves are defined as waves having wavelengths ranging from about
1 m to 1 mm, which correspond to frequencies between 300 MHz (1 m) and
300 GHz (1 mm).
Fig. 7 Microwave and conventional heating patterns (With Permission from: [28])
Supercritical Water Gasification (SCWG) Technology for Municipal Solid Waste. . .
187
glasses and plastic components are separated for recycling and reuse as aggregates,
while the metals are extracted for recycling. The water used in the system is usually
trapped and recycled in the process, and the final wastewater is discharged as an
effluent stream which removes pollutants from the process. The great advantages of
this technology are its ability on the treatment of all form of wastes in the MSW
stream, including those that are not recyclables like metals. The technology also
enables the reuse option for plastics, as well as sterilising plastic wastes before the
recycling. The metals and plastic wastes treated using this technology are always
comparable to virgin materials. The autoclaving plants are modular in nature because
they are made up of units which can be added or taken away based on changes of the
waste stream or volume of the wastes. Huge development is witnessed in using the
cellulosic pulps from the treated wastes using this technology in biofuel production.
3.3 Microwave Technology
Microwave technology is becoming widely used in the globe, in the treatment and
remediation of environmental problems related to municipal solid waste. Since the
first use of this technology in the 1940s by Percy Spencer, microwave heating is
constantly getting serious attention by different researchers across the globe
[26, 27]. In recent years, microwave technology is proven to be an attractive
technology for the treatment of municipal solid wastes in addition to many astonishing applications in different areas of human life. Microwave technology operates
by delivering direct energy to the microwave absorbing material for complete
heating of the material from the outside and inside as shown in Fig. 7. Microwave
operates in the region between the electromagnetic spectrum and infrared radiation
region. Microwaves are defined as waves having wavelengths ranging from about
1 m to 1 mm, which correspond to frequencies between 300 MHz (1 m) and
300 GHz (1 mm).
Fig. 7 Microwave and conventional heating patterns (With Permission from: [28])
Supercritical Water Gasification (SCWG) Technology for Municipal Solid Waste. . .
187