(57) Mineral fines reduce OPC content in concrete, mortar and other cementitious compositions, typically in combination with a pozzolanically active SCM. Mineral fines can replace and/or augment a portion of hydraulic cement and/or fine aggregate. Mineral fines can replace a portion of cement binder and fine aggregate as an intermediate that fills a size void between largest cement particles and smallest fine aggregate particles. Supplemental lime can enhance balance of calcium ions in the mix water and/or pore solution. Supplemental sulfate can address sulfate deficiencies caused by high clinker reduction, use of water reducers and/or superplasticizers, and SCMs containing aluminates. Concentrated or pure carbon dioxide (CO2) can be used to passivate alkaline values in highly alkaline materials, such as concrete washout fines, CKD, class C flyash, incinerator ash, bottom ash, or biomass ash. CO, passivation or sequestration can be carried out before, during or after forming an initial concrete mix.
(71) Roman Cement, LLC, Salt Lake City, UT (US)