Apollo: A Patent Pending Mobile Device for Onsite Carbonation of Recycled Concrete Aggregate

The concrete industry faces a massive economic and environmental challenge as quality virgin aggregates become increasingly difficult to source. Recycled concrete aggregate (RCA) is readily available yet has remained drastically underutilized throughout the nation's transportation industry due to performance challenges with various factors critical for concrete production, including water absorption coefficient and alkali-silica reaction history. The proposed project completes the development of a new, mobile, and scalable device called Apollo™, capable of carbonating recycled concrete at ready mix concrete plants or in the field at a construction site. Apollo™ is a patent-pending device that brings carbonation capabilities to ready-mix plant operators and contractors with an advanced rolling process that fundamentally changes the economics of RCA carbonation. The project objective is to demonstrate carbonated RCA's performance properties, complete a 40-yard infrastructure project, and begin user testing with ready-mix concrete plants that have signed letters of support. Adopting waste streams for paving applications is a common practice, with supplementary cementitious materials (SCMs) and recycled asphalt pavement (RAP) widely used in the industry today. Scalable carbonation eliminates RCA's performance challenges and turns one of our most significant waste streams into a quality aggregate source for cost savings.