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Systems analysis and its interpretation. Life cycle assessment (LCA): aims to evaluate the environmental burdens associated with a certain product or service in a cradle-to-grave perspective, from raw material extraction to waste management and final disposal.
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Life cycle assessment (LCA): aims to evaluate the environmental burdens associated with a certain product or service in a cradle-to-grave perspective, from raw material extraction to waste management and final disposal. Standardisation is made through the framework of ISO, the International Organization for Standardization Source:Pernilla Tidåker
Raw material acquisition Processes Transport Manufacture Use Waste management Source:Pernilla Tidåker
We work with an “expanded system” • In all scenarios the same amount of valued functions are produced, either by the waste system or by the compensatory system (external system) Waste system Compensatory system Product Source:Jan-Olov Sundquist, IVL
Total system scenario 1-n Source:Jan-Olov Sundquist, IVL
Impact categories to be considered in an LCA • Resources - Energy and materials • Resources - Water • Resources - Land • Impacts on human health (toxicological and non-toxicological impacts, excluding and including work environment) • Global warming • Depletion of stratospheric ozone • Acidification • Eutrophication • Photo-oxidant formation • Eco-toxicological impacts • Habitat alterations and impacts on biological diversity Source:Pernilla Tidåker
Data are collected…and aggregated Inventory Characterisation Weighting NOx NH3 P etc. Eutrophication Index CO2 CH4 N2O Global warming Source:Pernilla Tidåker Title
Acidification • 2 NH3+4 O2 2 NO3- + 2 H2O + 2H+ • 2 NO2+½ O2 + H2O 2 NO3- + 2H+ • 2 SO2+½ O2 + H2O 2 SO42- + 2H+ • NH3 andNOx are not acidifying if they are taken up by plants instead of being oxidized to NO3- or if the NO3- is taken up, because when taken up by the root it is exchanged for OH-. Source:Pernilla Tidåker
Remember… It is a great difference between potential and actual environmental impacts. Source:Pernilla Tidåker
Which environmental effect is most important? • Global vs local • Long-term vs short-term • Normalization: Compare the system under study to total national emissions Source:Cecilia Sundberg
Normalized emissions from biowaste Source:Cecilia Sundberg
ORWARE, LCA and waste management • Waste occurs in most production systems – waste management included in most LCAs (but for food LCAs, it is often only included for the packaging) Waste management models, applicable to various wastes a useful tool in LCA ORWARE: mass flow model, including LCA assessment methodology Source:Cecilia Sundberg
Functional unit, valued products Heat Core system incineration Waste Power Functional unit Heat production Heat Core system Landfill Waste Power production Power Functional unit Complementary or alternative production Which is the complementary production system? Source:Cecilia Sundberg
Complementary systems • Marginal production: • If I would not produce heat from waste – how would that heat be produced? • If I produce more heat from waste – what other heat will not be produced? • Short term marginal : changes within existing infrastructure/production capacity • Long term marginal : changes in supply or demand will drive investment • The goal and scope of your study guides the choice of complementary systems Source:Cecilia Sundberg
Carbon budgeting • Biogenic carbon is considered neutral, no GWP • Most common assumption in LCA • This can be justified – and it can be questioned! Source:Cecilia Sundberg