Ammonium bisulfite is widely used in water treatment processes to remove or neutralize chlorine and chloramines. It acts as a reducing agent, effectively dechlorinating water to make it safer for discharge into the environment or for use in industrial applications. In the pulp and paper industry, it is employed as a bleaching agent to break down lignin and brighten paper products. Additionally, it serves as a preservative in the food industry, particularly in preventing discoloration and spoilage in fruits and vegetables. In oil and gas operations, it is utilized as an oxygen scavenger to prevent corrosion in pipelines and equipment. Its versatility also extends to photography, where it is used in developing solutions to stabilize images.