Hydrochloric acid has a wide variety of uses. In steel production, hydrochloric acid is used to clean (or "pickle") the steel to remove scale building prior to further processing. Before galvanizing or production of finished products such as nails it is necessary to first pickle the steel.
There are numerous uses of hydrochloric acid in the chemical industry. Hydrochloric acid is used to produce water treatment chemicals such as poly-aluminum chloride (PAC) and ferric chloride. Both PAC and ferric chloride are clarifying agents used to remove particulate matter from drinking water and industrial wastewaters. Hydrochloric acid is also used in the preparation of sodium chlorate
Hydrochloric acid is used in the oil & gas industry to help increase the production rate of oil wells and in the process of separating water from oil after extraction of oil sands.