Benefits of delayed addition of rutin on the thickening time and compressive strength of oil well cement

The addition mode of rutin has a significant effect on cement hydration. This paper investigated the benefits of delayed addition of rutin on the thickening time and compressive strength of oil well cement. The results showed that the rutin of delayed addition had little effect on ion concentrations in cement paste whereas the premixed rutin promoted the formation of ettringite (AFt). Cement pastes with delayed addition of rutin had lower consistencies. The delayed addition of rutin prolonged the thickening time, mainly because of its adsorption on the surface of the first formed hydration products. In addition, the delayed addition of rutin improved the dispersion of cement particles. Compared with premixing mode, the delayed addition of rutin had weaker effect on cement hydration after two days. As a result, hardened cement pastes (HCPs) with delayed addition of rutin had lower porosity, finer pores and better compressive strength development. The results of this paper have important implications for improving cementing quality and reducing cementing costs.