A Review on Desulfurization Technologies of Blast Furnace Gases

Abstract

The blast furnace gas, a low-calorific value fuel, is worthy of recycling. However, the sulfuric contents in blast furnace gases would cause pipeline corrosion and air pollution that are adverse to reutilization of blast furnace gases. Therefore, desulfurization technologies of blast furnace gas are necessary, which have been recently attracting much attention. This article clarifies main sources and forms of sulfur in blast furnace gases. Then, COS/H₂S removal methods that are commonly used are introduced. In fact, blast furnace gases usually exist in low-temperature and low-pressure conditions, whose major components are N₂/CO/CO₂/H₂ and minor components are sulfide/chloride. When blast furnace gases are used as a fuel, the sulfuric component will be converted into SO₂ that causes severe air pollution to atmospheric environments. However, according to recent findings, once sulfides are removed ahead of the utilization process of blast furnace gases, other air-polluting components (e.g., hydrogen chloride) could be also removed via synergistic effects. In light of these characteristics, this article discusses the feasibility of various desulfurization methods suitable for blast furnace gases with the aim to provide useful information for the development of blast furnace gas desulfurization technologies.