CAREER: Modeling, Optimization, and Equilibrium Formulations for the Analysis and Design of Circular Economy Networks

目前贯穿整个产品供应链的提取-制造-使用-处置模式具有巨大的环境和社会经济影响，包括气候变化、生物多样性丧失、自然资源枯竭和污染。政策制定者和行业从业者支持过渡到循环经济(CES)以解决这些挑战。CES旨在重新设计当前的加工消费实践，以消除浪费和污染，以最高价值流通产品和材料，并再生自然。虽然概念上很简单，但由于缺乏关于执行和评估教育举措有效性的科学指导，教育网络的发展受到了阻碍。这个职业项目旨在通过开发建模、优化和平衡公式来分析和设计CE计划和网络，从而提高设计和评估CE的最新水平。拟议的研究将使研究人员能够设计CE战略，以加快价值链的发展，从而消耗更少的新资源，产生更少的污染。该研究还促进了博弈论在过程系统工程中的应用。这项研究的结果将被纳入卡内基梅隆大学基于项目的本科和研究生水平的工艺设计课程，以促进未来科学家和工程师的循环性和可持续性思维。计划为K-12的受众开展外联活动，其中包括：(1)为面向STEM的专门儿童期刊撰写文章；(2)举办两期实践讲习班，重点介绍工艺设计中的循环和可持续性概念以及利用计算机进行化学工艺设计和优化。为了开发和测试创建循环经济(CES)所需的数学工具，该项目分为三个研究目标。首先，将为不同的CE倡议开发数学模型，例如可用于延长货物和材料寿命的模型，以及利用使用后流程的模型。这些模型将被用来构建典型的多代理CE网络，其中每个代理采用由一个或多个CE倡议组成的策略。这些网络的传统(数学规划)优化将从多智能体的角度进行，以找到它们的策略之间的权衡。这些结果将被用于设计圆形指标，以便代理人从彼此的战略中受益。在第二个目标中，个别代理人将被视为以分散方式进行决策的自治实体。博弈论为这些代理人网络的形式化分析提供了框架。在非合作的同时博弈和序列博弈下，研究了原型网络的纳什均衡。通过比较纳什均衡解和网络最优解的相对循环效率，量化两者之间的差异。第三个目标涉及应用在前两个目标下开发的理论来设计两个CE网络，一个涉及聚对苯二甲酸乙二醇酯(PET)塑料瓶废物的回收和再利用，第二个审查与从报废产品中回收稀土(关键)矿物相关的CE。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

The current extract-make-use-dispose paradigm throughout product supply chains has enormous environmental and socioeconomic impacts, including climate change, biodiversity loss, depletion of natural resources, and pollution. Policymakers and industry practitioners support transitioning to Circular Economies (CEs) to solve these challenges. CEs aim to re-design current processing consumption practices to eliminate waste and pollution, circulate products and materials at their highest value, and regenerate nature. Although conceptually simple, the development of CE networks is hindered by the lack of scientific guidance on implementing and evaluating the effectiveness of CE initiatives. This CAREER project aims to advance the state of the art in designing and assessing CEs by developing modeling, optimization, and equilibrium formulations to analyze and design CE initiatives and networks. The proposed research will allow researchers to engineer CE strategies to accelerate the development of value chains that consume fewer new resources and produce less pollution. The proposed study also advances the use of game theory in process systems engineering. The results of this research will be incorporated into undergraduate and graduate-level project-based process design courses at Carnegie Mellon University to promote circularity and sustainability thinking in future scientists and engineers. Outreach activities are planned for a K-12 audience and include (i) writing articles for specialized STEM-oriented children’s journals and (ii) two hands-on workshops focusing on the concepts of circularity and sustainability in process design as well as the use of computers for chemical process design and optimization. To develop and test the mathematical tools needed to create Circular Economies (CEs), this project is divided into three Research Objectives. In the first, mathematical models for different CE initiatives will be developed, such as those that can be used to extend the life of goods and materials and those that exploit post-use processes. These models will be used to construct prototypical multi-agent CE networks, where each agent adopts a strategy consisting of one or more CE initiatives. Traditional (mathematical programming) optimization of these networks will be pursued from a multi-agent perspective to find trade-offs between their strategies. These results will be used to engineer circularity indicators so that agents benefit from each other’s strategies. In the second objective, individual agents will be treated as autonomous entities that base their decision-making in a decentralized manner. Game theory provides the framework for the formal analysis of these networks of agents. The Nash equilibria of the prototypical networks will be studied under non-cooperative simultaneous and sequential games. The difference between the Nash equilibrium solutions and the network-optimal solutions will be quantified by comparing the relative circularity efficiency of the two. The third objective involves the application of the theory developed under the first two objectives to design two CE networks, one involving the recovery and reuse of polyethylene terephthalate (PET) plastic bottle waste and the second examining CEs relevant to the recovery of rare earth (critical) minerals from end-of-life products.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.