A method of producing a cement composition with reduced carbon emissions may include: defining cement constraints comprising at least one cement property; calculating a set of cement compositions which satisfy the cement constraints, using cement property models corresponding to the cement constraints; calculating a carbon emission associated with each of the cement compositions in the set of cement compositions using a carbon footprint model; selecting a cement composition from the set of cement compositions; and preparing the cement composition.

Provided herein are compositions, methods, and systems comprising vaterite and magnesium oxide.

Provided herein are compositions, methods, and systems comprising vaterite and magnesium oxide.

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.

An accelerator powder for cement and also rapid-setting binder compositions which contain the accelerator powder and the use in mortar or concrete. The accelerator powder includes from 10 to 99.7% by weight of a water-insoluble mineral powder P and from 0.3 to 90% by weight of at least one compound V selected from the group consisting of alkali metal halides and alkaline earth metal halides, alkali metal nitrates and alkaline earth metal nitrates, alkali metal nitrites and alkaline earth metal nitrites, alkali metal thiocyanates and alkaline earth metal thiocyanates and hydroxyalkylamines or salts thereof, and mixtures thereof.

An accelerator powder for cement and also rapid-setting binder compositions which contain the accelerator powder and the use in mortar or concrete. The accelerator powder includes from 10 to 99.7% by weight of a water-insoluble mineral powder P and from 0.3 to 90% by weight of at least one compound V selected from the group consisting of alkali metal halides and alkaline earth metal halides, alkali metal nitrates and alkaline earth metal nitrates, alkali metal nitrites and alkaline earth metal nitrites, alkali metal thiocyanates and alkaline earth metal thiocyanates and hydroxyalkylamines or salts thereof, and mixtures thereof.

The present invention relates to a process for preparing a metal-chelate retarder by a sol-gel method. The method comprises the following steps: weighing calcium nitrate tetrahydrate, aluminum nitrate nonahydrate and ferric nitrate nonahydrate according to a certain mass ratio and adding them into deionized water; placing the mixed solution on a magnetic stirrer and stirring the mixed solution evenly; adding citric acid monohydrate or gluconic acid, ethylene glycol or glycerol, and placing the mixed solution into a water bath to react to obtain the metal-chelate retarder. The process of the present invention has a reliable principle, overcomes the defects of long production period, complex preparation and the like of the existing retarders, has the advantages of simple process operation, cheap and easily available raw materials, and short production period. The prepared retarder has wide temperature adaptation range and adjustable thickening time, is suitable for large-scale industrial production, and has a wide market application prospect.

A method of cementing in a subterranean formation may include, activating an extended-life cement composition by mixing at least the extended-life cement composition with a liquid activated pozzolan additive comprising a carrier fluid and an activated pozzolan, wherein the extended-life cement composition comprises water, pumice, hydrated lime, and a set retarder; introducing the extended-life cement composition into a subterranean formation; and allowing the extended-life cement composition to set to form a hardened mass in the subterranean formation.

A method of cementing in a subterranean formation may include, activating an extended-life cement composition by mixing at least the extended-life cement composition with a liquid activated pozzolan additive comprising a carrier fluid and an activated pozzolan, wherein the extended-life cement composition comprises water, pumice, hydrated lime, and a set retarder; introducing the extended-life cement composition into a subterranean formation; and allowing the extended-life cement composition to set to form a hardened mass in the subterranean formation.