The emission of major smoke pollutants in the non-electricity industry remains high and difficult, which has become the focus of air pollution control and the key to improving regional air quality. The iron and steel industry is one of the key industries for the prevention and control of air pollution. The entire process of iron and steel smelting includes coking, sintering, ironmaking, steelmaking and steel rolling. The sintering and coking processes mainly produce exhaust gas such as smoke, dust and NOx.

The Ministry of Ecology and Environment issued the "Opinions on Promoting the Implementation of Ultra-Low Emissions in the Iron and Steel Industry". Existing steel companies and boilers in use will implement special emissions of sulfur dioxide, nitrogen oxides, particulate matter and volatile organic compounds from October 1, 2018. Limit: Existing enterprises in "2+26" cities should take effective measures to reach the special emission limit of air pollutants within the prescribed time limit. The main goal is to achieve ultra-low emission levels in principle for new steel projects (including relocation) across the country, and to promote ultra-low emission transformation of existing steel companies. By the end of 2020, significant progress will be made in the ultra-low emission transformation of iron and steel enterprises in key regions, and we will strive to complete the transformation of about 60% of the production capacity. The transformation is basically completed, and the country strives to complete the transformation of more than 80% of the production capacity.

The biggest difficulty in flue gas management in the iron and steel industry is denitrification. After the nitrogen oxide emission limit of the iron and steel industry is increased from 300mg/Nm3 to 50mg/Nm3, many enterprises are unable to meet the standard and urgently need treatment and transformation. After nearly two years of market practice and selection, SCR denitration technology has gradually occupied the mainstream of the denitration market in the iron and steel industry, and the market has huge room for growth.

With the country’s requirements for ultra-low emissions of iron and steel and the continuous advancement of ultra-low emissions, it is estimated that the scale of the future steel sintering air treatment dust removal and denitrification construction project will reach 40.32 billion yuan, including new denitrification projects, renovation denitrification projects and renovations The scale of the dust removal project will reach 33.6 billion yuan, 4.32 billion yuan and 2.4 billion yuan respectively.