Recently, Tangsteel Qinglong furnace charge pellet flue gas oxidation and denitration project put into production, smoothly the project is a joint EPC contract by TSIC and Kejie environmental protection.

This project is a national key special project 'pellet flue gas multi-pollutant ultra-low emission technology and demonstration' cascade oxidation-absorption denitration demonstration project. TSIC take 'green metallurgy' as positioning and combining with the actual situation of Qinglong furnace charge company, to provide the optimal technical solution in accordance with the principle of 'advanced, environmental friendly, safety, reliability and economy'.

On the basis of the original flue gas treatment system, the flue gas treatment facilities of ‘SNCR denitration + cascade oxidation denitration’ and related supporting projects are added in this project, so that the overall layout，implementation and production technology & equipment could reach harmony and unity.

SNCR denitration system includes ammonia water storage and delivery system, desalination system, metering and distribution part, spray atomization system and electrical equipment. Combining with the pellet production, set the ammonia water atomized spray gun in the chain grate machine preheating sectionⅡ, the temperature range is 900 ~ 1050 ℃ in this area, which can satisfy the SNCR denitration reaction temperature, so that to complete the initial removal of nitrogen oxides.

The post-mounted stepped-oxidation denitration system is set in front of the desulfurization tower entrance. Ozone is sprayed into the flue gas for stepped-oxidation of nitrogen oxides, to ensure the effective utilization of ozone，the oxidized high-valence nitrogen oxides are absorbed in the desulfurization tower to meet the emission requirements of nitrogen oxides finally.

By the embedded SNCR in preheating section II, the total NOx is reduced and the denitration load at the end section is greatly reduced. Through the concept of cascade process, the traditional problems that single-stage oxidation N₂O₅ with low generation efficiency and poor matching of the absorption system are broken through.

The COVID-19 is outbreak when the project is in its production sprint.

During the emergency period, TSIC take numbers of positive measures to overcome the difficulties, and provide comprehensive technical services for the owners both online and offline, so as to ensure the on-site battle against the epidemic and the project construction, and finally to ensure the project delivery on time. At the end of June, after the 168 hours’ continuous test run, all the equipment index meet the design requirements and come into production smoothly.

After the implementation of demonstration project of pellet flue gas oxidation and denitration technology, the pollutant purification index and operating energy consumption have been significantly improved, which is a major innovation of pellet flue gas ultra-low emission technology, and has good social and economic benefits. The successful operation of this project confirms the technical ability and service level of TSIC in the field of environmental protection, energy conservation and emission reduction, and sets an application model for the environmental protection and green development of pelletizing industry in China.