PROJECT DESCRIPTION
BACKGROUND
The generation of LandFill Gases (LFG), which are produced by the anaerobic decomposition of the organic waste fraction in landfills, is a major environmental challenge for climate change mitigation. The process naturally occurs in covered landfill once CH4 and oxygen (O2) counter gradients are in place. The behaviour and performance of this process is affected by several local climate factors, such as temperature and water content in the landfill covers.
The waste management sector was the fourth largest sector in the EU-15 in terms of its contribution to total greenhouse gas (GHG) emissions despite significant improvements (40% emission reduction) from 1990 to 2012. LFG is mainly composed of methane (CH4) and carbon dioxide (CO2), and its production lasts for several decades until the majority of the organic material is fully degraded. Both gases are powerful GHGs, with CH4 having a very high global warming potential, remaining a long time in the atmosphere. Although large GHG emission reductions in the waste disposal sector have been achieved by cutting CH4 emissions, CH4 still accounts for around two-thirds of waste-related emissions./p>
OBJECTIVES
The RE Mida projects overall objective was to demonstrate the technical, economic and environmental suitability of an innovative method to treat LFG with low calorific value through microbial CH4 oxidation to reduce its contribution to the greenhouse effect. Specifically, the project aimed to:
The project results would stimulate the implementation and upgrade of the EU Landfill Directive, with particular reference to the treatment of LFG with low calorific value that is technically and/or economically unsuitable using conventional technology.
RESULTS
The LIFE RE Mida project demonstrated the technical and economic viability of two technologies implemented for the biological oxidation of landfill biogas with low calorific value. The team showed that bio-oxidation techniques, under specific conditions have high oxidation performance and low lifecycle impacts while being lower in cost than conventional technology (flaring).
Specifically, the team demonstrated that the two tested pilot systems biofiltration and biowindows consistently achieve efficiency rates higher than 80% in the oxidation of methane and above 90% in the abatement of odorous compounds. The project further showed that developed technologies yield a range of environmental benefits: global warming, photochemical oxidation and acidification are reduced by at least 60% in the worse-case scenario assessed.
The project team also demonstrated that the risk associated with emissions of carcinogen compounds was reduced on average by 72%, while the cumulative risk associated with emissions of hazardous non-carcinogen compounds was reduced on average by 90% and the nuisance effects due to malodorous pollutants was reduced on average by 70%. Using the tested passive bio-filtering technologies can also reduce the cost of landfill post treatment by 34-61% depending on the size of the landfill; higher savings are achieved for small-size landfills when compared to a conventional combustion system.
The resultsconfirm that the project had the opportunity to provide concrete indications for the update of the EU regulation concerning the management of biogas with low calorific content. Notably, the demonstration of the technical and economic viability of these systems could allow upgrading the BAT on this field and, potentially, upgrade the legislation at different levels. In this regard, LIFE RE Mida aimed to contribute, with a bottom-up approach, to the technical upgrading of Directive 1999/31/EC by promoting consultation concerning LFG management. The CH4 emissions from managed waste disposal on land quantified by EEA amount to 86 113 thousands of tonnes of CO2 equivalent accounting for the 2% of the total GHGs emissions in 2016 in EU. In case of a large-scale application of the tested technologies, the indirect environmental impact could be significant considering that the amount of closed landfill sites all around Europe is rapidly increasing.
In light of this, the project team was already included in the group of experts in charge of revising the national regulation on landfills. The process, which is in progress, is expected to lead to the inclusion of the bio-oxidation techniques among the suitable treatments for the oxidation of landfill biogas with low calorific content.
Further information on the project can be found in the project's layman report and After-LIFE Communication Plan (see "Read more" section).
