Sanitary landfills for Municipal Solid Waste (MSW) disposal have been identified as one of the mostimportant anthropogenic sources of methane (CH4) emissions; in order to minimize its negative effectson the environment, landfill gas (LFG) recovery is a suitable tool to control CH4 emissions from a landfillsite; further, the measurement of CH4 emissions can represent a good way to evaluate the effectiveness ofLFG recovering systems. In general, LFG will escape through any faults in the landfill capping or in the LFGcollection system. Indeed, some areas of the capping can be more permeable than others (e.g. portions ofa side slope), especially when considering a temporarily capped zone (covered area that is not expected toreceive any further waste for a period of at least 3 months, but for engineering reasons does not have apermanent cap yet). These areas, which are characterized by abnormal emissions, are usually defined as‘‘features’’: in particular, a feature is a small, discrete area or an installation where CH4 emissions significantlydiffer from the surrounding zones. In the present study, the influence that specific features haveon CH4 emissions has been investigated, based on direct measurements carried out in different seasonsby means of a flux chamber to the case study of Palermo (IT) landfill (Bellolampo). The results showedthat the flux chamber method is reliable and easy to perform, and the contoured flux maps, obtainedby processing the measured data were found to be a suitable tool for identifying areas with abnormal(high) emissions. Further, it was found that a relationship between methane emission rates and landfillside slope can be established. Concerning the influence of the temporary HDPE cover system on CH4recovery efficiency, it contributed to a significant decrease of the free surface area available for uncontrolledemissions; this aspect, coupled to the increase of the CH4 volumes collected by the LFG recoverysystem, led to a significant increase of the recovery efficiency.
|Numero di pagine||8|
|Stato di pubblicazione||Published - 2013|
All Science Journal Classification (ASJC) codes
- Waste Management and Disposal