CO2-sequestering ability of M20 grade concrete with bio-char and iron ore tailing powder

The research aims to investigate the CO₂-sequestering ability of M20 grade concrete with biochar and Iron ore Tailing Powder (ITP). The biochar was prepared by slow pyrolysis of corn stover. The obtained biochar were categorized in two series as untreated biochar and biochar subjected to pre-treatment by heating until it catches fire. The fine aggregate in the concrete was replaced with biochar at 0%, 5%, 10% and 15%. The iron ore tailing powder obtained by crushing and sieving of iron ore waste products. The cement was replaced with ITP at 0%, 25% and 50% by its weight. Water to binder ratio was maintained at 0.45, the workability of the concrete was maintained with the help of super plasticizer. The compressive strength test, CO₂ uptake, porosity and mercury intrusion porosimetry test were conducted to understand the effect of biochar and ITP in concrete. The test result indicate that the mix containing pre-treated biochar with 25% ITP substitution has the maximum CO₂ sequestration capacity without compromising its strength characteristics.