CARBONACEOUS EXTENDERS FOR FLEXIBLE CEMENT

摘要

A flexible cement stableat high temperatures contains anextender that is a finely ground carbonaceousmaterial, for example a bituminouscoal and/or a finely groundcoke prepared from coal and/or liquidhydrocarbons. Preferred cokes aremade from bituminous coals and frompetroleum, heavy oil, and oil from tarsands, oil shales or oil sands. The carbonaceousmaterial is present in anamount up to 100 percent by weight ofcement and the particle size is preferablyfrom 1 to 1000 microns. The carbonaceousmaterial is also effective asan extender, and the slurries and set cementshave low specific gravity. Optionaladditives include silica and Wollastonite.