Effect of Ammonia Injection on the Iron Ore Sintering Process: Reducing Fossil Fuel Consumption and Carbon Emissions

The experiment involving ammonia injection was conducted to minimize solid fuel consumption and carbon emissions during the sintering process of iron ore. The sintering bed temperature, sintered ore quality, combustion efficiency, and pollutant emission under different ammonia injection concentrations and coke ratios were investigated. The experimental findings indicate that the injection of ammonia has a positive impact on the thermal mode of the sintering bed, leading to an increased yield of sintered ore and an improved tumbler index. Additionally, ammonia injection enhances the fuel combustion efficiency and reduces CO emissions. Compared with the traditional case that without ammonia injection, the yield under 1.5% vol ammonia injection increased from 63.69 to 74.78%, the tumbler index increased from 54.9 to 60.7%, and the average combustion efficiency increased from 89.42 to 93.42%. Under 1.0% vol ammonia injection, it is possible to decrease the coke ratio from 4.5 to 3.5% without weakening the sintered ore quality and the solid fuel consumption ratio and carbon emissions can be reduced by 22.2%.