Life Cycle Assessment (LCA) is a powerful tool to evaluate the environmental impacts of any product or activity. The main feature of LCA is the holistic approach: i) the studied system encompasses the entire life cycle of the product or activity, meaning throughout the different life cycle stages of raw resource extraction, material production, manufacturing, use, and end-of-life; ii) the environmental impacts are expressed according to different categories, namely the ecosystem, the human health, and resources. With such a view, it is possible to refer about possible burden shift from one phase of the life cycle to another, or from one impact category to another, when analysing a product system.
LCA has been applied to several sectors, among which waste management sector collected a large number of theoretical studies and applications to real world, as the support to waste management planning. LCA applications in waste management date back to the late 1990s, with an explicit mentioning of LCA by the Waste Framework Directive (Directive 2008/98/EC).
LCA has still a fundamental role in helping the development of waste management system supporting decision and, as clearly described in a recent review article published in Waste Management Journal 1 , by international experts in waste management and LCA, there are six areas in which LCA can still provide beneficial support to WM:
- understanding an existing waste management system;
- improving existing waste management systems;
- comparing alternative technologies/ technology performance;
- technology development/ prospective technologies;
- policy development/ strategic development and
- reporting.
In particular, LCA has a fundamental role in the support to technology development. Indeed, when developing a new process or technology, meaning characterized by a low TRL 2 , it is necessary to be aware of the environmental impacts of such a new process, especially in comparison to the existing ones, for the interest of several stakeholders (for instance potential investors, companies, authorities or decision makers). This can be done by applying LCA to the technologies under development, basing the inventory data on theory or lab- or pilot-scale systems. Eventually, making the effort of theoretical upscaling of the technology under development to industrial scale, to generate data for consumptions and yields. While consumption data (i.e. energy and utilities) might be obtained by real scale reactors and equipment design and modelling, in a rather reliable way, it is more challenging to predict real scale process yields, when data are available only at lab- or pilot-scale. To cope with this limitation, a range of values should be introduced in the analysis, to highlight how environmental performances are sensitive to some input parameters. This will help in identifying in which areas more robust data are required and to which part of the system under analysis the investigation efforts should be targeted. Eventually, such analysis can reveal the level of performances that the technology or process under development must reach for being considered an improvement with respect to existing processes or technologies.
In general, LCA can be applied at an early stage of development of processes or technologies in order to highlight the aspects which could be improved in terms of environmental impact, also in light of the low TRL. The results might highlight weak points and potential improvements and guide the efforts of the investigation procedure toward those sub-processes which represent the highest contributions to the overall environmental impact.
This way of applying LCA is even more current and relevant when looking at the demand of innovative processes and technologies able to provide answers to the challenge of circular economy. Indeed, more and more complex processes are being proposed for the recovery of materials – and fuels – from waste streams: their development must be accompanied by a deep care about their environmental impacts, especially in comparison with the current ones, and LCA is the tool able to support such a development process, with the aim of reaching a sustainable circular economy.
