Disclosed herein are compositions and methods for increasing the viscosity of a calcium-containing fluid by addition of a modifying agent. The resulting enhanced viscosity fluid may be used in a variety of applications including drilling, to create an enhanced-viscosity fluid, and demolition/mining to create an expansive putty for use in underwater and overhead applications.

A process for producing cement includes combining a cement precursor and a wax, wherein the wax includes alkyl ketene dimer wax and/or alkenyl ketene dimer wax, grinding the cement precursor and the wax to yield cement grains coated with the wax. A cement includes cement powder grains and a coating of wax on the Portland cement powder grains, wherein the wax includes alkyl ketene dimer wax and/or alkenyl ketene dimer wax. A process for making cementitious material includes combining a cement with water to yield a slurry, wherein the cement includes cement powder grains and a coating of wax on the cement powder grains, wherein the wax includes alkyl ketene dimer wax and/or alkenyl ketene dimer wax, and allowing the slurry to set.

Compositions may include a calcium lignosulfonate salt having a chemical structure (I), wherein a total number of syringyl groups is 2 to 10. The compositions may further include an alcohol, an aldehyde, and water. Cement slurries may include a lignosulfonate-based cement dispersant including a calcium lignosulfonate salt having a chemical structure (I), an alcohol, an aldehyde, and water, wherein a total number of syringyl groups in the chemical structure (I) is 2 to 10. The cement slurries may further include a cement and water. Methods may include introducing a cement slurry into a wellbore penetrating a subterranean formation, wherein the cement slurry comprises a lignosulfonate-based cement dispersant, a cement, and water, and allowing the cement slurry to set to a concrete in a downhole zone of interest. ##STR00001##

Disclosed herein are compositions and methods for sealing a leak in a well. In many embodiments, the leak is sealed by deploying a mixture of water and a phenolic curable resin into the well, wherein the resin polymerizes and hardens at and around the leak in the well. In various embodiments, the well may be an oil, gas, or geothermal well.