Abstract:

Focused on the problem of zonal-isolation failure in thermal recovery wells, this work investigated the feasibility of using high aluminum cement instead of common Portland cement in thermal recovery well cementing. Laboratory experiments show that the new cement has good stability and low fluid loss, and the microsilica added can effectively decrease the hydrate speed and restrain the transition of crystalloid at low temperature. The amount of microsilica added affects the stability of strength of the cement to some extent at high temperatures. Results show that with appropriate amount of microsilica the cement is of the character to prevent strength retrogression at high temperature and has good general properties, and thus can meet the needs of thermal recovery well cementing.

Key words: high aluminum cement, thermal recovery well, cementing, high temperature, strength retrogression