Tracking the Environmental Consequences of Circular Economy over Space and Time: The Case of Close- and Open-Loop Recovery of Postconsumer Glass.

Abstract

With the increasing globalization of waste-derived raw materials, region-oriented circular economy measures that stimulate resource recovery can cause far-reaching ripple effects in geographically dispersed markets, with unintended environmental effects. Identifying, quantifying, and characterizing these implications in a multiregional economic system remains challenging. This Policy Analysis aims to track these market-mediated environmental consequences over space and time with high material resolution. It explores a novel avenue of coupling consequential life cycle assessment and a time-series multiregional material-product chains model. The model is applied to two measures to recover postconsumer glass waste in the province of Quebec (Canada): improving closed-loop bottle-to-bottle resource recovery systems and deploying open-loop system for the marketing of glass powder as a supplementary cementitious material. Their environmental consequence trajectories (2030-2050) across a seven-industry and six-region competing symbiosis are examined. In both cases, cost-based optimized results highlight widespread adjustments in eastern North America trade patterns that are expanding over time in response to the coevolution of symbiotic industries. Between 55% and 94% of the environmental benefits are felt beyond Quebec borders. This information can help decision makers better anticipate the in- and cross-border scope of their measures and coordinate across jurisdictions to maximize overall environmental benefits.