Evaluating greenhouse gas impacts of organic waste management options using life cycle assessment

Abstract

Efforts to divert organics away from landfills are viewed by many as an important measure to significantly reduce the climate change impacts of municipal solid waste management. However, the actual greenhouse gas (GHG) impacts of organics diversion from landfills have yet to be thoroughly evaluated and whether such a diversion provides significant environmental benefits in terms of GHG impacts must be answered. This study, using California-specific information, aimed to analyse the GHG impacts of organics diversion through a life-cycle assessment (LCA). This LCA considered all aspects of organics management including transportation, materials handling, GHG emissions, landfill gas capture/utilization, energy impacts, and carbon sequestration. The LCA study evaluated overall GHG impacts of landfilling, and alternative management options such as composting and anaerobic digestion for diverted organic waste. The LCA analysis resulted in net GHG reductions of 0.093, 0.048, 0.065 and 0.073 tonnes carbon equivalent per tonne organic waste for landfilling, windrow composting, aerated static pile composting, and anaerobic digestion, respectively. This study confirms that all three options for organics management result in net reductions of GHG emissions, but it also shows that organics landfilling, when well-managed, generates greater GHG reductions. The LCA provides scientific insight with regards to the environmental impacts of organics management options, which should be considered in decision and policy-making. The study also highlights the importance of how site and case-specific conditions influence project outcomes when considering organic waste management options.

Greenhouse gas emissions from organic waste composting

“…In this sense, turned pile composting systems resulted in an overall higher impact than aerated systems (confined aerated windrows and tunnel) because of fuel consumption and turning that implies the above-mentioned increase in gas emissions (Colón et al 2012;Kong et al 2012).…”

Greenhouse Gas Emission During Composting and Vermicomposting of Organic Wastes – A Review

“…Challenges of global climate change, stringent legislative directives (1999/31/EC), limited landfilling sites, and advanced green technology has led to the diversion of organic fraction of wastes (biodegradable) from landfill sites and adoption of alternative waste management options to increase and improve waste reduction, recovery, and recycling . Though well‐managed municipal solid waste landfilling is a viable environmental option, in terms of reducing GHG impacts, for managing organic wastes as compared to other waste management options such as composting and anaerobic digestion, it is generally agreed that reduced landfilling activities could lead to lower environmental impact including GGE and energy demand. The adoption of aerobic treatment techniques like composting and vermicomposting for treatment of organic wastes seems to be the most sustainable option .…”

Environmental assessments of biological treatments of biowaste in life cycle perspective: A critical review

“…(CES) and AE (UOL + CAE) GWP, TEU, SOX and NOX DAKong et al (2012) USA CT, PC, T, ES (CES) and AE (UOL + CAE) GWP DA Yoshida et al(2012)USA CT, PC, T, ES (CES) and AE (UOL + CAE) GWP DA Dong et al(2013)China CT, T, ES (CES) and AE (CAE) GWP DATakataet al (2013) Japan PT, T, ES (EUI + CES) and AE (UOL + CAE) GWP DA Zhao and Deng (2014) Hong Kong CT, PT, T, ES (EUI + CES) and AE (UOL + CAE) GWP, AP, EP, ODP, POF, , ES (EUI + CES) and AE (UOL + CAE) GWP, TA, TE, FE, ME and DFR DA Cremiato et al (2018) Italy PC, CT, PT, T, ES (EUI + CES) and AE (CAE) GWP, AP, EP, POCP and Dab DA Edwards et al (2018) Australia CT, PT, T, ES (EUI + CES) and AE (UOL + CAE)…”