1.
n. [Well Completions, Well Workover and Intervention]
A mixture of hydrofluoric
acid [
HF] and
hydrochloric acid [
HCl] or organic acid used as the main fluid in a
sandstone matrix treatment. Hydrochloric acid or organic acid is mixed with HF to keep the
pH low when it spends, thereby preventing detrimental precipitates. The name
mud acid was given to these mixtures because they were originally developed to treat
damage from siliceous drilling muds. Mud acid is also called
hydrofluoric-hydrochloric acid.