Get Ammonium Bisulfide Corrosion

Ammonium chloride is used as a flux in preparing metals to be tin coated, galvanized or soldered. It works as a flux by cleaning the surface of workpieces by reacting with the metal oxides at the surface to form a volatile metal chloride.

Ammonium chloride and amine hydrochloride salts are highly water-soluble, highly corrosive and form an acidic solution when mixed with water.

► Ammonium Chloride may cause an asthma-like allergy. Future exposure can cause asthma attacks with shortness of breath, wheezing, cough, and/or chest tightness. ► Exposure may affect the kidneys.

Corrosion rate 0.1—1.0 mm/year.

Ammonium chloride either as gas, solid, or in solution is corrosive [10]. NH4Cl at near aqueous dew point or at high concentration level is highly corrosive, and is generally less corrosive when diluted.

When the effluent is cooled below 250 F, the gases combine to form ammonium bisulfide (ABS) salt. To prevent accumulation of the salt, water is injected before the reactor effluent cools to the ammonium bisulfide deposition temperature.

Ammonium Chloride (NH4Cl) corrosion is an aggressive form of localized, underdeposit corrosion commonly found in overhead equipment and piping associated with crude and hydroprocessing units. This happens when ammonia and hydrochloric acid in the vapor react to form NH4Cl salt.

Ammonium bisulfide corrosion is an aggressive corrosion occurring in several refinery units, including hydrotreaters. Only sour water strippers suffer more serious sour water corrosion than hydrotreaters. The most troublesome hydrotreating units are those processes for desulfurization of heavy petroleum fractions.