Eco-efficient cements: Potential economically viable solutions for a low-CO2 cement-based materials industry

Advances in understanding hydration of Portland cement

Recent advances in understanding the role of supplementary cementitious materials in concrete

Rice husk (RH), an agricultural waste, is abundantly available in rice producing countries like China, India, Bangladesh, Brazil, US, Cambodia, Vietnam, Myanmar, and South East Asia. Despite the massive amount of annual production worldwide, so far RHs have been recycled only for low-value applications. In recent years, many rice mills in rice producing countries have started using RH for the energy production for mill operations as well as household lighting in rural regions. Burning of RHs produces the rice husk ash (RHA). The disposal in landfills or open fields can be problematic and may cause a serious environmental and human health related problems due to the low bulk density of RHA. Several ways are being thought of for disposing RHA by making its commercial use. The amorphous silica forms the main component (83–90%) of RHA. The amorphous silica rich RHA has wide range of applications. High-value applications and current research investigations such as the use of RHA in manufacturing of silica gels, silicon chip, synthesis of activated carbon and silica, production of light weight construction materials and insulation, catalysts, zeolites, ingredients for lithium ion batteries, graphene, energy storage/capacitor, carbon capture, and in drug delivery vehicles are presented. Use of RHA in potential future applications is also discussed. It is suggested that the amorphous silica rich RHA could become a potential resource of low cost precursor for the production of value-added silica based materials for practical applications.

Potential applications of rice husk ash waste from rice husk biomass power plant

Supplementary cementitious materials: New sources, characterization, and performance insights

The present study investigated the effects of mesoporous amorphous rice husk ash (RHA) on compressive strength, portlandite content, autogenous shrinkage and internal relative humidity (RH) of ultra-high performance concretes (UHPCs) with and without ground granulated blast-furnace slag (GGBS) under different treatments. The results were compared with those of UHPCs containing silica fume (SF). Because of the mesoporous structure, RHA can absorb an amount of aqueous phase to decrease the free water content and to supply thereafter water for further hydrations of cementitious materials. Hence, compressive strength of RHA-blended samples is enhanced. The highly water absorbing RHA delays and slows down the decrease in the internal RH (self-desiccation) of UHPCs, and hence strongly mitigates autogenous shrinkage of UHPCs compared to SF. The combination of GGBS and RHA or SF improves the properties of UHPC. These results suggest that RHA acts as both highly pozzolanic admixture and internal curing agent in UHPC.

Rice husk ash as both pozzolanic admixture and internal curing agent in ultra-high performance concrete

Research review of cement clinker chemistry

Early hydration of SCM-blended Portland cements: A pore solution and isothermal calorimetry study

Effect of rice husk ash and other mineral admixtures on properties of self-compacting high performance concrete

Mesoporous structure and pozzolanic reactivity of rice husk ash in cementitious system

Horst-Michael Ludwig

Papers

Rice husk ash as both pozzolanic admixture and internal curing agent in ultra-high performance concrete

Research review of cement clinker chemistry

Early hydration of SCM-blended Portland cements: A pore solution and isothermal calorimetry study

Effect of rice husk ash and other mineral admixtures on properties of self-compacting high performance concrete

Mesoporous structure and pozzolanic reactivity of rice husk ash in cementitious system