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Activity 5.1

The scope of this activity was to evaluate the ISWM TINOS concept from the environmental perspective by using the life cycle analysis principles. In specific, this study is aiming to find the environmental footprint by performing quantified environmental indicators. Emphasis is given to the estimation of the global warming impact assessment, as well as to other impact assessment categories, such as the acidification, the eutrophication, several types of toxicity etc. The results are given in equivalent units, in order to be comparable and mainly replicable. According to the implementation method applied in each case, the relevant profiles are given (characterization, normalization, weighting, and single score). The implementation methods used are the IMPACT 2002+, EDIP 2003, as well as the single issues methods of IPCC 2007 and Greenhouse Protocol focusing on the global warming impact. The approach methodology for the life cycle analysis is given in this deliverable. The choice of the appropriate life cycle implementation methodology is considered one of the most crucial parameter. Furthermore the strategic determination of the system boundaries has significant impact to the estimation of the environmental footprint.  The scenarios given in this deliverable have been built in function with the indicators related to Tinos Island.  Hence, a database was created according to the data collected during the visit studies in Tinos Island.

The examined scenarios are distinguished in the two concepts. The first corresponds to the implementation of the pilot project of LIFE ISWM TINOS in Pyrgos and Panormos areas and the second one corresponds to the full implementation of the concept in Tinos Island. Hence the examined cases are the following:

A)    ISWM TINOS concept in Pyrgos-Panormos

  • ISWM-TINOS concept with composting process
  • ISWM TINOS concept with anaerobic digestion
  • Mesophilic digestion and Thermophilic digestion
  • Sub-scenarios with composting of solid fraction and co-digestion of liquid fraction with sewage sludge
  • Dump process

B)    Full scale implementation plan in Tinos

  • ISWM-TINOS concept with composting process
  • ISWM TINOS concept with anaerobic digestion
  • Mesophilic digestion and Thermophilic digestion
  • Landfill process (without energy recovery)

The results prove that the applied concept in ISWM TINOS is more environmental friendly compared to the current waste management method applies in Pyrgos Townn (dumping process). According to the IMPACT 2002+ method, the environmental benefit in global warming impact terms reaches the value of 184 kg CO2eq/t waste, while according to the IPCC method (more focusing on the global warming impact) the value reaches the value of 338 kg CO2eq/t waste. By moving to the full implementation concept, the environmental benefits are increasing, since higher rate of application of the project is expected to be implemented. In specific according to the IPCC 2007 method, the saving CO2eq emissions are estimated at 555 kg CO2eq/t waste comparing to a landfill process, while according to the IMPACT 2002+ method the respective saving CO2eq emissions are estimated at 477 kg CO2eq/t waste.

In what concerns the application of the anaerobic digestion, the anaerobic digestion process performs less global warming impact than the composting process due to the emission saving from the avoidance of the electricity generation. Higher biogas yield achieved in thermophilic digestion process in comparison with the mesophilic process, leading to increase of emission savings. In pilot scale, the difference between the composting and mesophilic digestion is estimated at 7.78 kg CO2/t waste, while the respective environmental benefit for the thermophilic digestion is estimated at 9.38 kg CO2eq/t waste. Moving to the full implementation scale in Tinos Island, the environmental benefit of the anaerobic digestion comparing to the compost process is 21.76 kg CO2eq/t waste and 26.23 kg CO2eq/t waste for the examined cases of mesophilic and thermophilic anaerobic digestion respectively.

The results prove that the anaerobic digestion is clearly more effective in the reduction of the environmental footprint in highly populated cities/towns. Hence the proposed waste management concept is appropriate for application in other Greek islands, as well as in remote/mountainous areas by giving valuable score to the overall environmental footprint.