A method of cementing a well casing or liner in a well bore wherein an annulus exists around the exterior of the casing or liner. The method comprises the step of placing a foamed cement slurry composition in the annulus. A method of treating a well bore comprising the steps of: (a) filling an uncased portion of the well bore with a foamed cement slurry composition; (b) allowing the cement composition to harden; and (c) drilling a hole through the hardened cement composition along at least a portion of the uncased portion of the well bore.

Well cementing using permeable cement

A method of stimulating a subterranean formation using a foamed cement composition. When hardened, the cement composition has a permeability of at least about 0.3 darcies. The inventive formation stimulation method comprises the steps of: (a) injecting the foamed cement composition into the formation at a pressure sufficient to fracture the formation and (b) allowing the cement composition to harden in the formation.

Fracturing with foamed cement

To cement the annulus around a casing string in a well penetrating an underground formation, a column of cement slurry which is or includes a foam cement slurry is placed in the annulus and allowed to set. The amount of gas contained in the slurry and the set cement is such that the density in the cement slurry column and the cement in the annulus increases with increasing depth.

Method of cementing wells with foam-containing cement

The primary function of well cement is to provide casing support and zonal isolation for the life of a well (Thiercelin et al., 1998; Singamshetty, 2004; Iverson et al., 2008). Failure to achieve one or both of these conditions can lead to a migration of fluids up the wellbore and result in both economic and ecological disasters, as exemplified by the Deepwater Horizon oil spill on April 20, 2010. To avoid these kinds of failures, the cement must have sufficient strength to secure the casing in the hole and withstand the stresses of drilling, perforating, enhanced oil recovery, and hydraulic fracturing and also be able to keep the annulus sealed against the formation. 
This thesis analyzes and presents in detail some of the mechanical and physical properties of atmospherically generated foamed cements typically used in deep offshore wells in the Gulf of Mexico. Both static and dynamic measurements were taken across a range of foam qualities and include permeability, porosity, compressive strength, Young’s modulus (E), and Poisson’s ratio (ν). Investigating the properties of a range of foam qualities and cement recipes provides better understanding of the effect that different amounts of entrained air can have on cement performance and reliability. To better represent the behavior of cements in the wellbore, we subjected cements to pressure cycling and the measurements were analyzed over the range of these pressures. Our results show how these foamed cements behave and will prove to be a good baseline for future testing on cements generated under in-situ conditions.

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A Quantitative Assessment of Atmospherically generated Foam Cements: Insights, Impacts, and Implications of Wellbore Integrity and Stability.

Publisher Summary This chapter discusses all the aspects of foamed cement technology. The thermodynamic and physico-chemical bases for foamed cements are explained, followed by a discussion of foam rheology. The design of a foamed cement treatment is described, including laboratory testing, pre-job planning, and engineering. The execution of a foamed cement job is covered, together with safety considerations, the configuration of field equipment, and the mixing procedure. The field applications for which foamed cement is appropriate are described, including some case histories. Foamed cements are more difficult to design and place than conventional systems, but the risk is less than that associated with stage cementing. Foamed cement is carefully evaluated for its merits on each type of cementing treatment.

C. A. Aldrich

Papers

Strength, Permeabilities, and Porosity of Oilwell Foam Cement