Principle of Desulfurization and Denitrification Process in Coke Ovens of Coking Plants

    Coking plants are upstream industries in the steel sector and, like steel mills, are key targets for national flue gas pollution control. The flue gas generated by coke ovens in coking plants contains certain amounts of SO? and NOx, making the management of flue gas desulfurization and denitrification a priority for enterprise control.

     Shiheng Environmental Protection has numerous cases of flue gas treatment in domestic coking plants. For example, the flue gas desulfurization and denitrification equipment projects for Coke Ovens #1, #2 and #5, #6 at a coking plant in Tangshan. These projects each involve the construction of a set of flue gas desulfurization and denitrification purification devices, which must meet national environmental protection standards upon installation and use.

       Coking Plant Coke Oven Desulfurization and Denitrification ProjectFor the desulfurization and denitrification system of Coke Ovens #1 and #2, after on-site survey and analysis, the dense-phase tower desulfurization + SCR denitrification technology was adopted. This solution fully utilizes the synergistic combination of various subsystems such as desulfurization and denitrification, achieving collaborative treatment of air pollutants in coke oven flue gas. It delivers excellent desulfurization, denitrification, and dust removal effects with strong technical and economic benefits.

       SDS Dry Tower Desulfurization + SCR Denitrification Process Flow for Coking Plant Coke Ovens:

       1. The flue gas produced by coke oven combustion is first heated in a hot blast stove, raising the temperature to the range of 280~320°C, providing suitable temperature conditions for the denitrification process.    

       2. The heated flue gas is then uniformly mixed with ammonia injected through the ammonia injection grid. The NOx denitrification treatment is carried out in a quasi-low-temperature SCR denitrification reactor. After denitrification, the NOx concentration in the flue gas should be ≤150mg/Nm3.

      3. The denitrified flue gas then undergoes waste heat recovery in a waste heat boiler and is subsequently sent to the coking plant's steam main. The cooled flue gas is treated in a dense-phase flue gas desulfurization tower, where dry desulfurization removes sulfur dioxide from the flue gas, along with HCl, HF, and nitrogen oxides. The SO? concentration in the flue gas is ≤30mg/Nm3.

       4. The desulfurized flue gas is then dedusted by a baghouse filter, and the treated exhaust gas meets standards for emission through the chimney. The desulfurizing agent collected on the filter bags can further absorb SO?. The dust concentration in the flue gas is ≤15mg/Nm3.