WELLBORE INTEGRITY: MODIFYING AND CHARACTERIZING OIL WELL CEMENT TO ENHANCE WELLBORE LOGGING AND PREVENT PERFORATING DAMAGES IN HYDRAULIC FRACTURED WELLS

Oil well cementing is considered as one of the foremost important and challenging operations in drilling. The main purpose of cement in wellbores is to provide zonal isolation, and support for casing. Properties of oil well cement should be taken into consideration to assure a high quality cementing job. The objective of this study was to investigate the effect of unconventional additives and contamination on oil well cement. In addition, self-healing oil well cement was developed to prevent perforation damages. Laboratory results showed that polycarboxylate enhanced the rheology and reduced the fluid loss of cement by up to 96%. Nanoclay increased the compressive strength by up to 71%, and reduced the fluid loss by up to 64%. Salt and drilling fluid contamination altered the properties of cement particularly compressive strength and rheology. The proposed self-healing cement retained up to 22% of its initial mechanical strength and yielded zero permeability.