Assumption | Ref. | ||
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Goal and scope | - Environmental impacts from upstream life cycle stages before the SW collection were excluded - Environmental impacts of the infrastructures, capital goods, and wastewater treatment from the treatment plants were also excluded - The collection and the source separation assumed to have no material and energy consumption | ||
LCI | MFA | Considered transfer coefficients are recycling process (25.5%-plastic,11%-paper, 0%-glass, 16.5%-aluminum), 35%-composting process, and 17%-incineration process | |
- Emissions of biogenic CO2 were assumed to be neutral | |||
Landfilling with gas recovery | - The efficiency of the landfilling system with gas recovery is 50% | ||
Recycling system | - Secondary products produced from the recycling process replace the production of alternative products. The potential avoidance of primary products (90%-plastic, 95%-glass, 90%-paper, 75%-aluminum) | ||
Composting process | - Compost produced from the composting process replaces the chemical fertilizers in S4. The potential avoidance of chemical fertilizer usage is 7.1 kg N, 4.1 kg P2O5, 5.4 kg K2O t− 1 of compost. | ||
Incineration process | - The electricity recovering efficiency at the incineration plant for S2 and S3 is 8% and for S4 20% - Electricity produced from incineration displaces an equivalent amount of electricity generated | ||
Transportation | - Transport distances 50 km (to landfill) 10 km (to composting plant) 100 km (to incineration plant) 50 km (to recyclable waste collection plant) - the process “Transport, municipal waste collection, 21 t lorry and freight, lorry” for waste transportation to the landfill site, composting plant, and incineration plant - the process “Transport, freight, lorry, unspecified” was selected for the transportation of recyclable waste to the treatment facility |