Technical Development of Waste Sector in Sweden: Survey

MASTER’S THESIS IN ENVIRONMENTAL STRATEGIES RESEARCH
P-G process is responsible for acidification, global warming, eutrophication, human toxicity,
marine ecotoxicity and terrestrial ecotoxicity impact categories. Emission from the process is
responsible for the environmental burdens since the P-G process occurs in the limited amount of
air; the volume of syngas is less, which is one of the key benefits of P-G process. If more air is
used in the process, higher volume of syngas is produced and more environmental burden would
be imposed.
Figure 16 shows the normalization graph of the model representing the level of significance for
different impact categories. Form the figure, P-G of MSW has significantly high environmental
impact on marine aquatic ecotoxicity, fresh aquatic ecotoxicity, global warming, human toxicity,
eutrophication, terrestrial eco-toxicity and acidification. Normalization graph shows that,
environmental burden of the P-G of MSW is primarily caused by the disposal of final residue.
Therefore, volume of final residue and the treatment of the residue in one of the key concern to
promote P-G as waste treatment technology as future of sustainable waste management system in
Sweden. Significant environmental impact categories are analyzed for P-G of MSW in the
following section.
Aquatic Depletion: P-G has significant impacts on marine and fresh aquatic categories. Disposal of
final residue is the primary cause for aquatic quality depletion. Vanadium Copper (ion) and
Selenium is the main disposal degrading aquatic environment and Nickel, Zinc and Antimony are
the primary pollutants for the aquatic depletion.
Global Warming Potential: Carbon dioxide, carbon monoxide emission is mainly causing global
warming impact. Disposal of final residue is also responsible for global warming impact. The
process of MSW treatment has lower GWP however, significant impact occurs during the
conversion of syngas to electricity from the process.
Human Toxicity: Pyrolysis-Gasification has significant environmental impact on human toxicity
and the impact is primarily associated with the process stage and for the disposal of final residue.
Arsenic, Cadmium, Mercury, Nickel, Nitrogen oxide and Hydrogen fluoride are the primary
pollutants for the Human toxicity which are emitted in the atmosphere and water by the P-G
process.
Terrestrial Ecotoxicity: P-G has a significant terrestrial ecotoxicity impacts. Mercury, Arsenic and
Nickel that are emitted from the process in the atmosphere are the primary cause for terrestrial
ecotoxicity.
Acidification: Disposal of final residue in thin environment causes acidification burden. However,
acidification can be avoided by the P-G process due to energy generation. Nitrogen oxide and
sulphur dioxide are the primary reason for the acidification impact and these gases are emitted in
the atmosphere during the process stages.
From the inventory analysis, major pollutants that cause environmental impacts due to the MSW
Pyrolysis-Gasification have been identified and the data are shown in Table 10.
KUNGLIGA TEKNISKA HÖGSKOLAN
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