The Use of Nanoaccelerator in Cement Slurries in Low Temperature Well Conditions

It has long been known that temperature during circulation and after cement placement is one of the most important parameters for slurry design and the success in cement production. Conventional cements and low density cement slurries usually take a long time to set and cannot provide significant compressive strength. Therefore, it is important to design appropriate low density cement slurries for low temperature conditions during surface casing cementation. In well cementing procedures, the slurry must be fluid for a sufficient time to allow the task to be completed. One of the problems that frequently happens in cementing a low temperature formation is a long setting time, in which the cement is influenced by low temperatures and the thickening time increases. To solve this problem, a unique cement system, which contains nanosilica, hollow spherical material, and class-G oil well cement, was developed for the first time. For this purpose, some additives such as; dispersants and fluid loss control agents were used in the cement system. The laboratory tests show that this slurry has a low density, excellent fluid loss control, no free fluid, right-angle-set, and a short thickening time (47 minutes) at low temperatures. The experimental results presented herein can help resolving problems in surface casing cementing.