I-Corps: Lightweight Aggregates from Waste Bottom Ash

这个I-Corps项目的更广泛的影响/商业潜力是从煤电工业未使用的废料底灰中生产可用于混凝土和岩土工程应用的轻质骨料。在美国，每年大约产生1.2亿吨的煤炭燃烧产物（如飞灰和底灰），其中37%被重复利用。这导致大量未使用的煤灰储存在现场的地表蓄水池中。从未使用的底灰中生产LWA将导致废物转化为可吸引混凝土和岩土市场的增值产品。生产出来的LWA可以作为骨料用于(a)结构轻质混凝土的生产，(b)混凝土的内部养护，(c)建筑、挡土墙和景观用混凝土砌块的生产，(d)隔热/隔音混凝土单元的生产，以及(e)高速公路、桥梁桥台、挡土墙和基础的轻质填充物。这个I-Corps项目将对从废底灰生产的轻质骨料（LWA）的市场规模和商业潜力有重要的了解。底灰残碳含量高，创新的烧结技术是利用残碳和适当的助熔剂制成由玻璃层包裹的多孔材料，具有火山灰反应性。这种新型材料将以可控比例具有活性非晶表面和惰性晶体多孔内部。该技术使用热力学模型，可以针对具有各种物理条件和化学成分的大范围底煤灰。

The broader impact/commercial potential of this I-Corps project is to produce lightweight aggregates (LWA) from unused waste bottom ash of coal electric power industry that can be used for concrete and geotechnical applications. Each year in the United States around 120 million tons of coal combustion products (e.g., fly ash and bottom ash) are generated of which 37% is reused. This has led to a large historical stock of unused coal ash stored in on-site surface impoundments. Production of LWA from unused bottom ash will result in conversion of waste material to value-added product that can attract concrete and geotechnical markets. The produced LWA can be used as an aggregate in (a) structural lightweight concrete production, (b) internal curing of concrete, (c) production of concrete masonry blocks for buildings, retaining walls and landscape, (d) production of thermal/sound insulating concrete units, and (e) lightweight fill for highways, bridge abutments, retaining walls, and foundations.This I-Corps project will lead to significant understanding of market size and commercial potential of lightweight aggregates (LWA) produced from waste bottom ash. Bottom ash has high residual carbon and the innovative sintering technology is to use this residual carbon with appropriate fluxing agent to create a porous material encapsulated by a glassy layer that exhibits pozzolanic reactivity. This novel material will possess an active amorphous surface and an inert crystalline porous interior in a controlled ratio. The technology uses a thermodynamic model and can target a wide range of bottom coal ashes with various physical conditions and chemical compositions.