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M. Gautam and M. Agrawal
energy consumption, and economic costs; to reveal the plausibility and limitations of
economic information in MSW management; to bring out the comparative assertions
in regulation of MSW management and to evaluate the compatibility of LCA with
the hierarchy of MSW management [12]. The present study, however, infuses the
LCA of MSW management with GHG emissions from cradle to grave for clear
understanding of gaseous emissions (Fig. 6).
4.2 Functional Unit and System Boundaries
Functional unit is a well-defined and measurable phase [48]. It provides a basis to
understand and compare the results of LCA at general and specific levels [48]. While
a system boundary defines the unit processes, i.e., stages, inputs as well as outputs
within the system. It comprises the total elements of the system upon which the
computations of impacts are based. The LCA of MSW management system ensures
the GHG emissions out of the inputs at various stages of management systems (Fig. 6).
In addition, both are allied to the generation of useful products such as compost, heat
and electricity. More specifically, it includes management of one tonne of MSW
with specific composition over a definite period of time to compare the alternative
scenarios [94]. Functional unit and system boundaries are comprised of following
five scenarios for clear illustration of baseline to advanced management processes.
4.2.1 Scenario 1
It is a baseline scenario for developed and developing nations, where maximum
proportion of MSW after collection is dumped to landfill sites having no provision
for leachate and gaseous collection. Landfill sites at baseline scenario may or may not
have gas flares. Thus, there is more harmful impact of scenario 1 on the environment
because of maximum releases of GHGs (CH 4 ) from the landfill sites (Fig. 6).
4.2.2 Scenario 2
Incineration or thermal treatment facilities equipped with baseline scenario led to
recovery of energy from MSW with subsequent generation of flue gas and ash.
Relatively less proportion of waste is generally utilized for energy recovery due to
high waste generation and less capacity of the incinerator [72]. In this scenario also
maximum proportion of MSW is disposed without proper pretreatment to landfills,
which consequently leads to high GHG emissions (Fig. 6).
M. Gautam and M. Agrawal
energy consumption, and economic costs; to reveal the plausibility and limitations of
economic information in MSW management; to bring out the comparative assertions
in regulation of MSW management and to evaluate the compatibility of LCA with
the hierarchy of MSW management [12]. The present study, however, infuses the
LCA of MSW management with GHG emissions from cradle to grave for clear
understanding of gaseous emissions (Fig. 6).
4.2 Functional Unit and System Boundaries
Functional unit is a well-defined and measurable phase [48]. It provides a basis to
understand and compare the results of LCA at general and specific levels [48]. While
a system boundary defines the unit processes, i.e., stages, inputs as well as outputs
within the system. It comprises the total elements of the system upon which the
computations of impacts are based. The LCA of MSW management system ensures
the GHG emissions out of the inputs at various stages of management systems (Fig. 6).
In addition, both are allied to the generation of useful products such as compost, heat
and electricity. More specifically, it includes management of one tonne of MSW
with specific composition over a definite period of time to compare the alternative
scenarios [94]. Functional unit and system boundaries are comprised of following
five scenarios for clear illustration of baseline to advanced management processes.
4.2.1 Scenario 1
It is a baseline scenario for developed and developing nations, where maximum
proportion of MSW after collection is dumped to landfill sites having no provision
for leachate and gaseous collection. Landfill sites at baseline scenario may or may not
have gas flares. Thus, there is more harmful impact of scenario 1 on the environment
because of maximum releases of GHGs (CH 4 ) from the landfill sites (Fig. 6).
4.2.2 Scenario 2
Incineration or thermal treatment facilities equipped with baseline scenario led to
recovery of energy from MSW with subsequent generation of flue gas and ash.
Relatively less proportion of waste is generally utilized for energy recovery due to
high waste generation and less capacity of the incinerator [72]. In this scenario also
maximum proportion of MSW is disposed without proper pretreatment to landfills,
which consequently leads to high GHG emissions (Fig. 6).