I-Corps: Carbon-negative supplementary cementitious materials for carbon-neutral concrete

I-Corps项目的更广泛影响/商业潜力是，通过加强二氧化碳矿化，将各种各样的负价值和低价值固体废物转化为高价值的混合补充胶凝材料。SCM是一种用于水泥和混凝土行业的商品。该技术的商业潜力得到了当前三个行业趋势的支持。首先，碳减排的巨大挑战将需要能够在千兆吨规模上部署的突破性技术。其次，水泥/混凝土行业是二氧化碳排放的主要来源，正在寻求替代scm来取代水泥进行深度脱碳。三是对各类铝硅酸盐固体废物进行有益利用，减轻其生态负担。拟议中的技术将同时满足这三个需求。这个I-Corps项目的基础是通过升级回收碱性铝硅酸盐固体废物来生产混合补充胶凝材料（SCM）。这些废物含有碱土金属和过渡金属的氧化物。提出的方法增强了这些金属元素的溶解，并通过控制碳酸化（二氧化碳吸收）将它们转化为碳酸盐颗粒。这个过程的副产物是无定形的铝硅酸盐相和杂质。最近的研究结果表明，如果比例适当，碳酸盐（如石灰石或白云石）和无定形铝硅酸盐（如煅烧粘土）可以协同作用，取代混凝土生产中高达50%的水泥，而不会影响混凝土的性能。该方法与新兴技术的不同之处在于，形成混合scm的成分（碳酸盐和铝硅酸盐）是通过负碳过程从固体废物中产生的，而不是挖掘自然资源。模拟和实验结果表明，当使用混合的SCMs代替部分水泥时，可以改变其组成，但产生与普通水泥基材料（如混凝土）相当的孔隙结构和力学性能。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识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 broader impact/commercial potential of this I-Corps project is the conversion of a broad range of negative-value and low-value solid wastes into high-value, blended, supplementary cementitious material (SCM) through enhanced carbon dioxide (CO2) mineralization. SCM is a commodity used in the cement and concrete industry. The commercial potential of this technology is supported by three current industry trends. First, the grand challenge of carbon reduction will require breakthrough technologies that can be deployed at gigaton scale. Second, the cement/concrete industry is a major source of CO2 emissions and is seeking alternative SCMs to replace cement for deep decarbonization. Third, various aluminosilicate solid wastes need to be beneficially used to mitigate their ecological burden. The proposed technology will simultaneously address these three demands.This I-Corps project is based on the production of blended supplementary cementitious material (SCM) through upcycling of alkaline aluminosilicate solid wastes. These wastes contain oxides of alkaline earth metals and transition metals. The proposed approach enhances the dissolution of these metal elements and converts them into carbonate particles through controlled carbonation (carbon dioxide uptake). Byproducts of this process are amorphous aluminosilicate phases and impurities. Recent research results have shown that if proportioned properly, carbonates (such as ground limestone or dolomite) and amorphous aluminosilicate (such as calcine clay) can act synergistically to replace up to 50% of cement in concrete production, without compromising the performance of concrete. What differentiates the proposed approach from emerging technologies is that the components (carbonates and aluminosilicate) forming the blended SCMs are produced from solid waste through a carbon-negative process, instead of excavation of natural resources. Simulation and experimental results have shown that the resultant blended SCMs, when used to replace part of cement, can change of composition but yield comparable pore structures and mechanical properties to normal cement-based materials such as concrete.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.