Patent ID: 6626242
Filing Date: 2003-09-30
Classification: C04B,C09K

Abstract:
A method for cementing oil and gas wells comprising the steps of:(a) providing a storable composition for cementing oil and gas wells containing blast-furnace slag as hydraulic material, activators, additives and an aqueous continuous phase forming a cementitious slurry, wherein the amount of activators in said composition based on the amount of slag is insufficient to effect the setting of the composition for at least 72 hours at ambient temperature, and wherein the storable composition comprises (1) from 200 to 500 lb of blast-furnace slag per each bbl of slurry to be prepared; (2) from 0.01 weight % to 13 weight % of activators, based on the weight of said slag; and (3) the balance of the composition being made up of a water-based fluid, and additives; (b) pumping the cementitious slurry into the well; and (c) allowing the cementitious slurry to set.