Methods and systems are presented in this disclosure for evaluating performance of cement fluid-loss-control additives and generating cement slurries with controlled fluid losses for cementing operations. A normalized pressure along a wellbore length can be first specified based on properties of the proposed cement slurry formulation and properties of the wellbore in a subterranean formation. A volume loss of a fluid of the proposed cement slurry formulation can be calculated using a model associated with the fluid obtained based at least in part on the normalized pressure and properties of the fluid. The proposed cement slurry formulation can be manipulated by adding one or more fluid-loss control additives to the proposed cement slurry formulation based on the calculated volume loss of the fluid to produce a preferred cement slurry.

The present disclosure is directed to chemical additives for geopolymer cements that can improve the rheological properties of geopolymer cements. These chemical additives include sulfates and selenates of a specific formula as well as hydroxycarboxylic acid salts of Li, Na, and K including but not limited to glycolic, lactic, citric, mandelic tartaric, and malic acids. The chemical additives for geopolymer cements disclosed herein can facilitate the uniform mixing, increase the time mixtures can be transported, and improve the ability to place and finish concrete and mortars made with the geopolymer cements.

The present disclosure is directed to chemical additives for geopolymer cements that can improve the rheological properties of geopolymer cements. These chemical additives include sulfates and selenates of a specific formula as well as hydroxycarboxylic acid salts of Li, Na, and K including but not limited to glycolic, lactic, citric, mandelic tartaric, and malic acids. The chemical additives for geopolymer cements disclosed herein can facilitate the uniform mixing, increase the time mixtures can be transported, and improve the ability to place and finish concrete and mortars made with the geopolymer cements.

The present invention refers to a manufacturing process of artificial pozzolan which has the final color gray. In order to perform the processes in the desired way, the kiln atmosphere shall contain low oxygen concentration and the presence of reducing agents. However the presence of carbon monoxide at the kiln outlet is not desirable, due to environmental impacts and the increase in specific heat consumption of the kiln. So the process described in this invention comprises the following steps: heating (1), which consists of heating the raw materials to a temperature between 100-350 C. until drying of the material to a moisture mass fraction of 0-5% (wet basis); mixing (2), which consists of mixing the dry raw materials from the heating process with the right proportion of fuel, in from 1% to 5% in mass fraction, according to the concentration of hematite present in the raw material; calcining (3), which consists of heating the fuel and raw materials blend to a temperature between 700-900 C., with oxygen concentration between 1-5% and, finally, cooling (4), which consists of an initial step of rapid decrease in pozzolan temperature until 600 C. and a final step of slow decrease in pozzolan temperature until 120 C.

An activated pozzolan composition includes a fine interground particulate blend of an initially unactivated natural pozzolan and a supplementary cementitious material (SCM) different than the initially unactivated natural pozzolan. The initially unactivated natural pozzolan may include volcanic ash or other natural pozzolanic deposit having a moisture content of at least 3%, and the activated pozzolan composition can have a moisture content less than 0.5% The initially unactivated natural pozzolan may have a particle size less than 1 mm before intergrinding with the SCM. The SCM used to activate the initially unactivated natural pozzolan can be initially coarse or granular with a size greater than 1-3 m and may include granulated blast furnace slag, steel slag, other metallurgical slag, pumice, limestone, fine aggregate, shale, tuff, trass, geologic material, waste glass, glass shards, basalt, sinters, ceramics, recycled bricks, recycled concrete, refractory materials, other waste industrial products, sand, or natural mineral.

An activated pozzolan composition includes a fine interground particulate blend of an initially unactivated natural pozzolan and a supplementary cementitious material (SCM) different than the initially unactivated natural pozzolan. The initially unactivated natural pozzolan may include volcanic ash or other natural pozzolanic deposit having a moisture content of at least 3%, and the activated pozzolan composition can have a moisture content less than 0.5% The initially unactivated natural pozzolan may have a particle size less than 1 mm before intergrinding with the SCM. The SCM used to activate the initially unactivated natural pozzolan can be initially coarse or granular with a size greater than 1-3 m and may include granulated blast furnace slag, steel slag, other metallurgical slag, pumice, limestone, fine aggregate, shale, tuff, trass, geologic material, waste glass, glass shards, basalt, sinters, ceramics, recycled bricks, recycled concrete, refractory materials, other waste industrial products, sand, or natural mineral.

Mining provides our society with many of minerals, metals, and gemstones for a wide variety of applications from mundane items through to expensive jewelry. But the mining operations generate waste and large empty shafts and stopes within the ground. It would beneficial to provide a lightweight material for backfill which can provide safer working conditions for miners as well as advantages in respect of weight reduction, reducing water consumption, rheology improvement and cost minimization. Equally, it would be beneficial for the lightweight backfill material to include mining tailings to reduce the impact external to the mine. However, the inclusion of mine tailings into a foam is counter-intuitive as mine tailings are generally characterized by a high proportion of small particles with sharp edges. However, embodiments of the invention provide just such a foam based mine backfill material.

Mining provides our society with many of minerals, metals, and gemstones for a wide variety of applications from mundane items through to expensive jewelry. But the mining operations generate waste and large empty shafts and stopes within the ground. It would beneficial to provide a lightweight material for backfill which can provide safer working conditions for miners as well as advantages in respect of weight reduction, reducing water consumption, rheology improvement and cost minimization. Equally, it would be beneficial for the lightweight backfill material to include mining tailings to reduce the impact external to the mine. However, the inclusion of mine tailings into a foam is counter-intuitive as mine tailings are generally characterized by a high proportion of small particles with sharp edges. However, embodiments of the invention provide just such a foam based mine backfill material.

The invention relates to an addition for producing thermally conductive mortars and structural concrete, said addition being a specific powdery formulation in each case, which, when added as an addition to a conventional concrete or mortar, allows the production of a structural concrete or mortar with improved thermal characteristics (thermal conductivity ). If the addition is added to a conventional concrete in a plant, a structural concrete with increased thermal conductivities is produced, which can adapt to the thermal requirements of the building, thereby being highly suitable for the heat activation of structures or the geothermal activation of foundations. The concrete containing the addition takes on special rheological characteristics which, inter alia, allows a self-compacting concrete to be produced. If the addition is added to a conventional mortar in a mixer, a mortar is produced with very high thermal conductivities which make it highly suitable for geothermal probes.

The invention relates to an addition for producing thermally conductive mortars and structural concrete, said addition being a specific powdery formulation in each case, which, when added as an addition to a conventional concrete or mortar, allows the production of a structural concrete or mortar with improved thermal characteristics (thermal conductivity ). If the addition is added to a conventional concrete in a plant, a structural concrete with increased thermal conductivities is produced, which can adapt to the thermal requirements of the building, thereby being highly suitable for the heat activation of structures or the geothermal activation of foundations. The concrete containing the addition takes on special rheological characteristics which, inter alia, allows a self-compacting concrete to be produced. If the addition is added to a conventional mortar in a mixer, a mortar is produced with very high thermal conductivities which make it highly suitable for geothermal probes.