Comparison of recycling and incineration of aluminium cans.
This project has been commissioned by Infinitum AS, the corporation that runs the deposit recycling scheme for beverage containers in Norway. The study is closely connected to previous work documented in the report ‘LCA of beverage container production, collection and treatment systems’ (Raadal et al., 2016a) and supplemented memo (Raadal et al., 2016b), as well as the report ‘Comparison of recycling and incineration of PET bottles’ (Raadal et al., 2017). The systems and major assumptions are based on these above mentioned documents.
The main goal of this study has been to compare the environmental impacts of a consumers’ choice to whether: a) use Infinitum’s deposit system in order to recycle their aluminium cans; or b) dispose of their aluminium cans together with their residual waste to incineration. The systems are analysed using an extended waste treatment model represented by the cases recycling and incineration, taking into account both the initial production of virgin aluminium cans and the avoided burdens from recycling and energy recovery.
The major conclusion is that Infinitum’s recycling system for aluminium cans clearly outperforms incineration of cans for the assessed environmental impact categories Climate Change, Cumulative Energy Demand (CED) and Fossil Resource Depletion.
On an annual basis (when distributing about 260 million litres beverage by aluminium cans), the potential Climate Change benefit from Infinitum’s recycling system (100% collection rate) compared to incineration is 34 000 and 71 000 tonnes CO2-equivalents, for European and Global aluminium production, respectively. This reduction potential corresponds to the annual emissions from respectively 23 000 and 48 000 passenger cars. Corresponding reduction potentials for Cumulative Energy Demand (CED) are 150 and 196 GWh primary energy for European and Global aluminium production, respectively, which correspond to about 14% and 18% of the annual end use of district heat related to Norwegian households. For Fossil Resource Depletion, the benefit of using the Infinitum system amounts to 91 and 175 GWh primary fossil resources for European and Global aluminium production, respectively. This corresponds to about 8% and 16% of the annual end use of district heat related to Norwegian households.
The annual environmental benefit from Infinitum’s system with the existing collection rate (85.8%%) compared to incineration, when assuming European aluminium production, is 25 000 tonnes CO2-equivalents, 129 GWh and 78 GWh for Climate Change, CED and Fossil Resource Depletion, respectively. For Global aluminium production, the benefit is 61 000 tonnes CO2-equivalents, 168 GWh and 150 GWh for Climate Change, CED and Fossil Resource Depletion, respectively.
The results are also given per can in order to compare the environmental impacts of the consumers’ choice to: a) use Infinitum’s deposit system in order to recycle their aluminium cans; or b) dispose of them together with their residual waste to incineration. The Climate Change benefit of using Infinitum’s system range from 0.05 to 0.1 kg CO2-equivalents per aluminium can for European and Global aluminium production, respectively. Corresponding results for CED and Fossil Resource Depletion are 0.23 to 0.30 kWh and 0.14 and 0.27 kWh primary energy per aluminium can for European and Global aluminium production, respectively.
As documented in Raadal et al. (2017), the difference in environmental impacts between recycling and incineration systems per functional unit remains the same whether one take multiple recycling loops or not into account. The reason for the equal results from the two models is that the difference in environmental loads between the systems increases proportionally according to the amount of material being recycled. Hence, the difference per functional unit (e.g. per kg material or per 1000 litres distributed beverage) remains the same.
However, it should be emphasised that a system which provides a steady supply of good quality recyclables has a large potential of replacing virgin material several times, and thereby to contribute to environmental benefit in every loop. The development of recycling systems with high recycling yield and quality is therefor of large importance in order to displace as much virgin material as possible in the future’s circular economy. Infinitum’s recycling system provides a steady supply of aluminium recyclables with a high yield and required quality, which can replace virgin aluminium several times. It is thus up to stakeholders, authorities and other parts of the aluminium can value chain to secure that a sufficient demand for recycled aluminium also is fulfilled, e.g. by providing efficient incentives, in order to secure a robust and environmentally successful recycling system.