Environmental impact assessment of energy recovery from food waste in Singapore

As a small and land scarce country, effective waste management is of outmost importance in Singapore. In this study the production of biogas through anaerobic digestion from the organic fraction of municipal solid waste (OFMSW) was compared to incineration of the waste. At the moment almost all of t...

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Detalles Bibliográficos
Autor principal: Bolin, Lisa
Formato: Second cycle, A2E
Lenguaje:sueco
Inglés
Publicado: 2010
Materias:
Acceso en línea:https://stud.epsilon.slu.se/1519/
Descripción
Sumario:As a small and land scarce country, effective waste management is of outmost importance in Singapore. In this study the production of biogas through anaerobic digestion from the organic fraction of municipal solid waste (OFMSW) was compared to incineration of the waste. At the moment almost all of the OFMSW in Singapore is incinerated. Three different scenarios were compared to the reference scenario (incineration): one with a large scale biogas plant that can treat half of all OFMSW in Singapore, one with a medium scale biogas plant about 15 times smaller than the large one and one with a small scale biogas plant that can treat waste from e.g. a shopping center or a food center. By using life cycle assessment (LCA) the different scenarios were compared in terms of global warming potential (GWP), acidification, eutrophication, energy use and land use. Two alternatives for utilization of the biogas were also compared through LCA, generation of electricity and the use of the biogas in heavy vehicles. From an environmental perspective production of biogas is a better way to treat OFMSW than incineration. When biogas is used for electricity generation the impact on GWP decreased about 80-130 CO2-eq/ton compared to the incineration scenario and also has lower impact on acidification and eutrophication. The result also showed that the use of the gas as a vehicle fuel gives about the same impact on GWP as when the gas is used to generate electricity but a much lower impact on both acidification and eutrophication. In terms of scale, the medium and large scale plants have less environmental impact than the small scale plant when the gas is used as a vehicle fuel. When the gas is used to generate electricity, the small scale scenario had higher GWP but lower acidification and eutrophication. The prevention of leakage of biogas during production and upgrading is crucial for the environmental impact on GWP. A leakage of only a few percent of the produced gas will lead to a loss of all the gain in saved green house gas emissions.