Researchers on the College of Illinois Urbana-Champaign have developed a Circularity Index that they are saying offers a complete methodology to quantify circularity in bioeconomic techniques. In a new paper, they define the strategy and apply it to 2 case research – a corn/soybean farming operation and the complete US meals and agriculture system.
“The standard financial system is linear – we produce, distribute, use, and eliminate merchandise. To extend sustainability, we have to develop a round economic system. Fairly than simply utilizing pure assets, we should recuperate, reuse, and recycle waste supplies,” mentioned lead creator Yuanhui Zhang, a professor within the Division of Agricultural and Organic Engineering (ABE).
“Round bioeconomy has develop into a sizzling subject in analysis, however most research are merely descriptive and there’s no approach to measure impacts. To maneuver the know-how ahead, we’d like measurements to quantify results, set up benchmarks, examine approaches, and establish weak spots,” he mentioned.
Within the paper, the researchers present a step-by-step define of the Circularity Index (CI), which measures circularity on a scale from 0 to 1. Zero means the system is totally linear, and 1 means it’s utterly round. The index contains eight classes: take, make, distribute, use, dispose, recuperate, remake, and reuse. The CI is computed by getting into out there information into every of those classes.
Zhang and his colleagues show methods to use the CI in two case research. The primary examines nitrogen biking in a corn-soybean farm within the Midwestern United States. The researchers enter manufacturing and output information for a interval of 8 years, and examine the impact of two totally different fertilizer therapies: urea versus manure. They calculate the CI to be 0.687 for urea and 0.86 for manure, indicating using manure fertilizer offers a extra round economic system.
Within the second case examine, Zhang and his colleagues take a look at the U.S. meals and agriculture system, specializing in vitality use. Drawing on nationwide information from the USDA, EPA, and DOE, they examine the present system with an method primarily based on the Atmosphere-Enhancing Meals Power and Water System framework, which entails restoration, remake, and reuse of natural waste. They discover the present system has a CI of 0.179, whereas the EE-FEWS method would result in a CI of 0.84.
“Our present manufacturing system depends totally on fossil gasoline, with some use of photo voltaic and wind vitality. However there’s little or no restoration of biowaste. If we recuperate meals waste and manure and switch it into vitality and fertilizer, we are able to recycle it again to the agricultural techniques it originates from. Using the EE-FEWS framework would tremendously enhance circularity of the U.S. bioeconomy,” Zhang defined.
The CI is a scalable methodology that can be utilized on totally different useful resource sorts and techniques, relying on the main target of curiosity. Sources will be minerals, resembling carbon or nitrogen, or non-mineral, resembling water or vitality. Methods can vary from a course of or a farm to an trade sector, a nationwide economic system, and even the worldwide economic system.
“We all know it’s essential to scale back fossil gasoline use, enhance renewable assets, and decrease our water consumption. However to take action successfully, we have to understand how a lot, and what the weak hyperlinks and tradeoffs are. The CI offers a single quantity that lets you set up a baseline, examine techniques, and decide finest methods for motion,” Zhang mentioned.
The CI can function an indicator to help coverage initiatives such because the United Nations’ Sustainable Growth Objectives. It additionally has potential industrial worth; for instance, meals corporations can show their manufacturing circularity to shoppers.
The paper, “A scalable index for quantifying circularity of bioeconomy techniques,” is printed in Sources, Conservation and Recycling [DOI: 10.1016/j.resconrec.2024.107821].
