Some embodiments of the present invention comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising RFA, hydraulic cement, and water; and allowing the settable composition to set. Other embodiments comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising RFA, calcium hydroxide (lime), and water; and allowing the settable composition to set. Other embodiments comprise a settable composition comprising: RFA, hydraulic cement, calcium hydroxide, natural pozzolan and water; and allowing the composition to set. Other embodiments comprise a settable composition comprising RFA and any combination of hydraulic cement, calcium hydroxide, slag, fly ash, and natural or other pozzolan.

Some embodiments of the present invention comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising RFA, hydraulic cement, and water; and allowing the settable composition to set. Other embodiments comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising RFA, calcium hydroxide (lime), and water; and allowing the settable composition to set. Other embodiments comprise a settable composition comprising: RFA, hydraulic cement, calcium hydroxide, natural pozzolan and water; and allowing the composition to set. Other embodiments comprise a settable composition comprising RFA and any combination of hydraulic cement, calcium hydroxide, slag, fly ash, and natural or other pozzolan.

An object of the present invention is to propose heat insulating structure which is excellent in thermal insulating properties and higher in strength. The heat insulating structure includes: an aerogel layer including aerogel particles, adhesive, and fibers; and a retainer which is provided to at least one face of the aerogel layer and includes fiber materials and binder resin. Each of the fibers is part of one of the fiber materials included in the retainer.

An object of the present invention is to propose heat insulating structure which is excellent in thermal insulating properties and higher in strength. The heat insulating structure includes: an aerogel layer including aerogel particles, adhesive, and fibers; and a retainer which is provided to at least one face of the aerogel layer and includes fiber materials and binder resin. Each of the fibers is part of one of the fiber materials included in the retainer.

An arrangement for producing a bulk material consisting substantially of foamed or blown mineral or oxide particles by thermal treatment of a bulk material of basic particles. The arrangement includes NIR halogen radiators for generating a NIR radiation field of radiation with an active component in a near infrared, NIR, range having a wavelength in a range between 0.8 m and 1.5 m and which has a power density of at least 50 kW/m.sup.2 for thermally treating the basic particles, a conveying device for transporting a layer or stream of the bed of basic particles through the radiation field, and a controller that controls heating of the bed of basic particles such that a maximum temperature in the layer or stream is in a temperature range between 600 and 1500 C.

Some embodiments of the present invention comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising remediated coal ash, hydraulic cement, and water; and allowing the settable composition to set. Other embodiments comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising remediated coal ash, calcium hydroxide (lime), and water; and allowing the settable composition to set. Other embodiments comprise a settable composition comprising: remediated coal ash, hydraulic cement, calcium hydroxide, natural pozzolan and water; and allowing the composition to set. Other embodiments comprise a settable composition comprising remediated coal ash and any combination of hydraulic cement, calcium hydroxide, slag, fly ash, and natural or other pozzolan.

Some embodiments of the present invention comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising remediated coal ash, hydraulic cement, and water; and allowing the settable composition to set. Other embodiments comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising remediated coal ash, calcium hydroxide (lime), and water; and allowing the settable composition to set. Other embodiments comprise a settable composition comprising: remediated coal ash, hydraulic cement, calcium hydroxide, natural pozzolan and water; and allowing the composition to set. Other embodiments comprise a settable composition comprising remediated coal ash and any combination of hydraulic cement, calcium hydroxide, slag, fly ash, and natural or other pozzolan.

Provided is a ceiling tile coated on at least one surface with an acoustically transparent coating which creates pores at the tile surface and comprises a high Tg polymeric binder, titanium dioxide, and particles selected from the group consisting of void latex particles, hollow glass beads, calcium carbonate, calcium magnesium carbonate, calcined clay and any combination thereof. Compositions for acoustically transparent coatings and methods for making a substrate surface acoustically transparent are provided as well.

Provided is a ceiling tile coated on at least one surface with an acoustically transparent coating which creates pores at the tile surface and comprises a high Tg polymeric binder, titanium dioxide, and particles selected from the group consisting of void latex particles, hollow glass beads, calcium carbonate, calcium magnesium carbonate, calcined clay and any combination thereof. Compositions for acoustically transparent coatings and methods for making a substrate surface acoustically transparent are provided as well.

The present disclosure relates to downhole fluid additives including a clay, a hydroxylated polymer, a cation, and water. The disclosure further relates to downhole fluids, including drilling fluids, spaces, cements, and proppant delivery fluids containing such as downhole fluid additive and methods of using such fluids. The downhole fluid additive may have any of a variety of functions in the downhole fluid and may confer any of a variety of properties upon it, such as salt tolerance or desired viscosities even at high downhole temperatures.