Consequences of Salting Well Cements

Salted cement remains active long after hydrating and hardening. In contact with less salted water, it exchanges salt for water through the permeable membrane continuum of the cement. Osmotic stresses in time produce multiple fractures. In Arctic uses, water imbibed from alternately thawed and frozen formations can freeze, expand, and rubble salted cement. Salt misuses can be reduced by balancing ion concentrations in cement with those in formations. Salt addition or any other mechanism of freezing point depression is unnecessary. Inclusion in the slurry of a small amount of hydrophilic material prevents expansion damage from the freeze of free water in hydrated cement.