Portland cement has high embodied energy and embodied carbon associated with its manufacture. In many construction applications, the need for concrete and mortar abrasion resistance requires the consumption of significantly higher amounts of Portland cement for higher concrete and mortar compressive strength. The invention comprises a new method for producing a chemically inert, low embodied energy and carbon mineral additive, with specific hardness and particle size, during Portland cement manufacturing that replaces a significant portion of the Portland cement by mass in the final composition. Alternatively, the mineral additive is produced separately and combined with Portland cement. The resulting mineral additive Portland cement composition has significantly lower embodied energy and carbon and imparts significantly higher abrasion resistance to concrete and mortar.

Portland cement has high embodied energy and embodied carbon associated with its manufacture. In many construction applications, the need for concrete and mortar abrasion resistance requires the consumption of significantly higher amounts of Portland cement for higher concrete and mortar compressive strength. The invention comprises a new method for producing a chemically inert, low embodied energy and carbon mineral additive, with specific hardness and particle size, during Portland cement manufacturing that replaces a significant portion of the Portland cement by mass in the final composition. Alternatively, the mineral additive is produced separately and combined with Portland cement. The resulting mineral additive Portland cement composition has significantly lower embodied energy and carbon and imparts significantly higher abrasion resistance to concrete and mortar.

The present invention primarily relates to the use of a mixture capable of biocementation as a means of preventing or reducing plant growth, preferably weed growth. The invention also relates to a method for preventing or reducing plant growth, preferably weed growth, on/in a substrate.

The present invention primarily relates to the use of a mixture capable of biocementation as a means of preventing or reducing plant growth, preferably weed growth. The invention also relates to a method for preventing or reducing plant growth, preferably weed growth, on/in a substrate.

Methods, compositions, and tools for use in creating rapidly forming plugs in situ in subterranean formations. In one instance, the disclosure provides a method that includes: placing a first pill comprising a calcium-aluminate-based cement composition at a plug location within the wellbore with the tubing; and placing a second pill comprising an alkaline fluid composition into the wellbore adjacent to the first pill with the tubing. In some cases there is a spacer fluid or spacer device between the first pill and the second pill. In some cases tubing having a mixing device is located at the bottom of the tubing in the wellbore to aid I mixing the first pill and the second pill to facilitate a chemical in situ reaction of the first pill and the second pill. The reaction between the first pill and the second pill forms a set plug at the plug location.

Methods, compositions, and tools for use in creating rapidly forming plugs in situ in subterranean formations. In one instance, the disclosure provides a method that includes: placing a first pill comprising a calcium-aluminate-based cement composition at a plug location within the wellbore with the tubing; and placing a second pill comprising an alkaline fluid composition into the wellbore adjacent to the first pill with the tubing. In some cases there is a spacer fluid or spacer device between the first pill and the second pill. In some cases tubing having a mixing device is located at the bottom of the tubing in the wellbore to aid I mixing the first pill and the second pill to facilitate a chemical in situ reaction of the first pill and the second pill. The reaction between the first pill and the second pill forms a set plug at the plug location.

A cementitious blend composition and a concrete mix composition preferable for making concrete resistant to high temperatures and alkaline conditions, particularly for making durable concrete for constructing an alumina digester tank in an aluminum smelter. The cementitious blend composition includes at least one hydraulic cement, silica fume (SF), and natural pozzolan (NP), wherein a weight percent ratio of at least one hydraulic cement:SF:NP in the cementitious blend composition lies in the range of (24-63):(5-44):(32-40) with the sum of the weight percentages of the at least one hydraulic cement, the SF, and the NP not exceeding 100%. The concrete mix composition comprises water and the cementitious blend composition, wherein a weight ratio of the water to the cementitious blend composition is 0.2-0.5, and wherein the concrete mix composition has a content of the cementitious blend composition of 400-550 kg/m.sup.3.

A cementitious blend composition and a concrete mix composition preferable for making concrete resistant to high temperatures and alkaline conditions, particularly for making durable concrete for constructing an alumina digester tank in an aluminum smelter. The cementitious blend composition includes at least one hydraulic cement, silica fume (SF), and natural pozzolan (NP), wherein a weight percent ratio of at least one hydraulic cement:SF:NP in the cementitious blend composition lies in the range of (24-63):(5-44):(32-40) with the sum of the weight percentages of the at least one hydraulic cement, the SF, and the NP not exceeding 100%. The concrete mix composition comprises water and the cementitious blend composition, wherein a weight ratio of the water to the cementitious blend composition is 0.2-0.5, and wherein the concrete mix composition has a content of the cementitious blend composition of 400-550 kg/m.sup.3.

Embodiments of a dry mix for producing a concrete composition are provided. The dry mix includes aggregate, cement, and bed ash. The bed ash contains the combustion product of a fluidized bed coal combustion reaction. Additionally, embodiments of a method of preparing the dry mix and embodiments of a method of preparing a concrete composition are provided. The dry mix is also suitable for repairing soil slips, and embodiments of a method of repairing a soil slip are also provided.

Embodiments of a dry mix for producing a concrete composition are provided. The dry mix includes aggregate, cement, and bed ash. The bed ash contains the combustion product of a fluidized bed coal combustion reaction. Additionally, embodiments of a method of preparing the dry mix and embodiments of a method of preparing a concrete composition are provided. The dry mix is also suitable for repairing soil slips, and embodiments of a method of repairing a soil slip are also provided.