Gas Emissions from Municipal Solid Waste Landfills: A Comprehensive Review and Analysis of Global Data

Abstract

Mitigation of global climate impacts from landfilling of
municipal solid waste (MSW) requires a broad understanding of the
multitude of factors influencing gas generation and subsequent emissions.
Despite recent advances in both measurement and prediction
of emissions of gas from MSW landfills, there have been few efforts to
collectively gather, analyze, and interpret global gas emissions data.
Therefore, a comprehensive review and analysis of literature data was
performed herein to document landfill gas generation, composition,
emissions, and factors influencing emissions from MSW landfills on a
global basis. In particular, global methane, nitrous oxide, and non-methane
volatile organic compound (NMVOC) flux measurement data were
compiled to summarize and compare the data according to continent,
country, climate, and landfill operational practices. Compiled fluxes were
highest for methane (− 4.50 × 101
to 4.15 × 104
g/m2 day), followed by
nitrous oxide (− 2.50 × 10–
3 to 3.75 × 101
g/m2 day), and NMVOCs (−
2.00 × 10–
3 to 7.32 × 10–
1 g/m2 day). Among the NMVOCs surveyed,
measured fluxes of oxygenated compounds, including alcohols and
ketones were highest, ranging from − 1.81 × 10–
5 to 2.20 × 10–
2 g/m2
day. In addition, fluxes of the aromatics, alkanes, reduced sulfur compounds,
and F-gases were consistently high. Flux generally increased
with increasing organics content of the waste mass, decreasing cover
thickness, and increasing average air temperature. Lower fluxes of landfill
gases were obtained in dry climates. Both developed and developing
countries were responsible for high fluxes. While methane is the
main gas of concern in greenhouse gas investigations, consistent and
considerable measurement of nitrous oxide and NMVOC releases from
landfills globally indicate the potential for high contributions from trace
gas species to whole-site landfill gas emissions. The trace gas contributions
become particularly significant when emissions are converted to
CO2-
equivalents. Overall results of this literature review can be used to
verify initial estimates of national inventory models and as baseline data
to inform future strategies focused on managing global greenhouse gas
and NMVOC emissions from MSW landfills