Disclosed is a foamed cementitious composition which limits or eliminates aggregate, especially porous lightweight aggregate and uses a lower than usual water to cementitious composition weight ratio. The stable cementitious foam mixtures may be employed to make cement boards and other cement products. The foamed cementitious composition was made with additions of PVOH foaming stabilizer and surfactant foaming agents to make foam water or by entrain air into cementitious slurry mixtures. The cementitious mixtures have a limited amount or preferably no perlite and no lightweight aggregate. The resulting foamed mixture had foam bubbles with size in the range of 50 to 200 m. After setting the foamed cementitious composition the resulting set board has air cells with size in the range of 50 to 200 m.

Disclosed is a foam modifier, e.g., useful for gypsum or cement slurries. The foam modifier comprises a fatty alcohol that is added to a gypsum or cement slurry that includes foaming agent, such as an alkyl sulfate surfactant. The fatty alcohol can be a C.sub.6-C.sub.16 fatty alcohol in some embodiments. The use of such a foam modifier can be used, for example, to stabilize the foam, reduce waste of foaming agent, improve void size control in the final product, and improve the gypsum board manufacturing process.

Disclosed is a foam modifier, e.g., useful for gypsum or cement slurries. The foam modifier comprises a fatty alcohol that is added to a gypsum or cement slurry that includes foaming agent, such as an alkyl sulfate surfactant. The fatty alcohol can be a C.sub.6-C.sub.16 fatty alcohol in some embodiments. The use of such a foam modifier can be used, for example, to stabilize the foam, reduce waste of foaming agent, improve void size control in the final product, and improve the gypsum board manufacturing process.

A well cementing composition comprises water, an inorganic cement, a gas generating agent and a gas stabilizer. The gas generating agent may contain materials that release hydrogen gas, carbon dioxide gas or nitrogen gas or combinations thereof. The gas stabilizer comprises an aqueous mixture comprising polyglycols, oxyalkylates and methanol, or coco trimethyl ammonium chloride, or a mixture comprising ammonium fatty alcohol ether sulfate and ethylene glycol monobutyl ether, or combinations thereof. When used to cement a subterranean well, the compositions improve the compressive strength, increase the rate at which compressive strength develops, preserve cement homogeneity, or enhance cement expansion or a combination thereof.

A well cementing composition comprises water, an inorganic cement, a gas generating agent and a gas stabilizer. The gas generating agent may contain materials that release hydrogen gas, carbon dioxide gas or nitrogen gas or combinations thereof. The gas stabilizer comprises an aqueous mixture comprising polyglycols, oxyalkylates and methanol, or coco trimethyl ammonium chloride, or a mixture comprising ammonium fatty alcohol ether sulfate and ethylene glycol monobutyl ether, or combinations thereof. When used to cement a subterranean well, the compositions improve the compressive strength, increase the rate at which compressive strength develops, preserve cement homogeneity, or enhance cement expansion or a combination thereof.

An apparatus for preparing foam for incorporation into cementitious slurry comprises a conduit having an inlet for receiving a gas feed and a surfactant feed, and an outlet for allowing the exit of foam. The conduit houses a porous plug that provides a partial barrier to fluid flow along the conduit, the plug comprising a plurality of particles that are packed in a regular array and that define a three-dimensional network of pores extending therebetween. The apparatus comprises a resilient component located between the plug and the conduit.

A high temperature lightweight thermal insulating material is formed from a mixture that includes cement or silica sand, water and a foaming agent. The foaming agent can be an aluminum powder or a surfactant. The insulating material has a maximum use temperature greater than about 600 degrees Celsius.

Disclosed is a method and system for blending a foam modifier with foaming agent online, e.g., as may be particularly useful for gypsum or cement slurries. The foam modifier comprises a fatty alcohol that is added to a gypsum or cement slurry that includes foaming agent, such as an alkyl sulfate surfactant. The fatty alcohol can be a C.sub.6-C.sub.16 fatty alcohol in some embodiments. The use of such a foam modifier can be used, for example, to stabilize the foam, reduce waste of foaming agent, improve void size control in the final product, and improve the gypsum board manufacturing process.

Disclosed is a method and system for blending a foam modifier with foaming agent online, e.g., as may be particularly useful for gypsum or cement slurries. The foam modifier comprises a fatty alcohol that is added to a gypsum or cement slurry that includes foaming agent, such as an alkyl sulfate surfactant. The fatty alcohol can be a C.sub.6-C.sub.16 fatty alcohol in some embodiments. The use of such a foam modifier can be used, for example, to stabilize the foam, reduce waste of foaming agent, improve void size control in the final product, and improve the gypsum board manufacturing process.

The present invention relates to the field of oil and natural gas well cementation engineering, in particular to a foam stabilizer composition, foamed cement slurry and an additive composition thereof. The foam stabilizer composition comprises C6-C20 alkyl amido alkyl amine oxide, C6-C20 alkyl amido alkyl betaine, and triterpenoid saponin compound. The foam stabilizer composition provided in the present invention is helpful for forming foamed cement slurry that has high foam stability, and the foam stabilizer composition can work with other active components in the foamed slurry additive composition provided in the present invention to enable the foamed cement slurry that contains the additive composition to obtain low density, high foam stability, low permeability, and high compressive strength, which is especially applicable to well cementing operation in an oil and natural gas exploration and development process.