Microstructure Investigation on Nano-Geopolymer Cement Cured under HPHT Condition

Drilling in high pressure and high temperature (HPHT) conditions place extreme stresses on the cement sheath and affect the integrity of the cement. It such conditions, the design of the cement is important and it must possess properties to ensure the cement slurry to remain pumpable long enough to allow placement and also have sufficient density to overbalance the formation pressure. Apart from that, the cement also should be environmentally friendly and should not cause damage or contamination to underground formation.
Utilizing industrial waste such as fly ash as raw materials, geopolymer cement has been highlighted as a better alternative to widely used, Ordinary Portland Cement (OPC). Manufacturing process of OPC proven to emit large amount of carbon dioxide (CO2), one of the main greenhouse effect (GHG). While, in terms of performance, OPC creates high permeability between cement particles when exposes to HPHT conditions inside the wellbore. Despite proven to have superior mechanical properties, geopolymer cement still encountered problems when applied in the same condition.