Used as a preservative in pharmaceuticals and food products to prevent oxidation and spoilage. Commonly applied in wine and beverage production to maintain freshness and color. Employed in water treatment to remove chlorine and dissolved oxygen, protecting pipelines and boilers from corrosion. Also utilized in the textile industry for bleaching and dyeing processes, and in photographic development as a developing agent. Effective in flue gas desulfurization to reduce sulfur emissions in industrial exhaust systems.