What are the waste gas treatment technologies for lime kiln and how to reduce environmental pollution
Lime shaft kiln generates a large amount of exhaust gas containing pollutants such as particulate matter, sulfur dioxide (SO ₂), and nitrogen oxides (NOx) during the production process, posing a threat to the environment. To reduce pollution, it is necessary to adopt a multi technology collaborative exhaust gas treatment system.
Dust removal technology is the fundamental link in exhaust gas treatment. Efficient bag filter filters flue gas through filter bags, intercepts particulate matter, and achieves purification goals. This equipment has a large air volume and high dust removal efficiency. The filter bag material is made of high temperature resistant and corrosion-resistant synthetic fiber filter materials such as PPS and PTFE to adapt to the characteristics of lime kiln exhaust gas.
Wet desulfurization technology is the mainstream, using limestone gypsum method. After entering the absorption tower, the exhaust gas comes into full contact with the sprayed limestone slurry, and SO ₂ undergoes a chemical reaction to generate calcium sulfite, which is then oxidized to calcium sulfate (gypsum) by an oxidation fan. This technology has high desulfurization efficiency, but it requires a gypsum dehydration system to achieve resource utilization.
Selective catalytic reduction (SCR) is the core of denitrification technology. Waste gas reacts with reducing agents (ammonia or urea) under the action of a catalyst, reducing NOx to harmless nitrogen and water. This technology requires selecting the catalyst type based on the exhaust gas temperature to ensure denitrification efficiency.
In addition, the use of clean energy alternatives (such as natural gas and electricity) and efficient combustion technologies (such as oxygen enriched combustion and staged combustion) can reduce the generation of pollutants. Waste heat recovery technology converts the thermal energy in exhaust gas into steam or electricity, achieving energy cascade utilization. The intelligent monitoring system monitors emission data in real-time, dynamically adjusts processing parameters, and ensures the stable operation of environmental protection facilities.
Through the combination of the above technologies, lime kiln can achieve ultra-low emissions, significantly reduce pollution to the atmospheric environment, and promote the green transformation of the industry.
