Environmental protection waste gas treatment technology for mechanical lime kiln
With increasingly strict environmental policies, the treatment of exhaust gas from mechanical lime kilns has become a key link in the industry's technological upgrading. Modern processing technology has formed a multi-level purification system to ensure emissions meet standards.
Main pollutants and treatment difficulties
The exhaust gas from lime kilns mainly contains dust (30-50g/Nm ³), SO ₂ (200-800mg/Nm ³), NOx (300-600mg/Nm ³), and a small amount of fluoride. The core governance difficulty lies in:
The flue gas temperature fluctuates greatly (80-250 ℃)
Strong dust adhesion (containing CaO component)
The amount of exhaust gas varies dynamically with production capacity
Mainstream processing technology
Efficient dust removal system
Combination process of cyclone dust removal and bag dust removal, dust removal efficiency>99.5%
Using membrane filter material to solve the problem of CaO dust agglomeration
Integrated desulfurization and denitrification
Semi dry desulfurization: Spray Ca (OH) ₂ slurry, desulfurization rate ≥ 90%
SNCR denitrification: Inject urea solution into the kiln at 850 ℃ to reduce NOx emissions by 60%
Deep purification device
Wet electrostatic precipitator: processing ultrafine particles such as PM2.5
Activated carbon adsorption: removal of dioxins and heavy metals
Technological development trends
Intelligent control system automatically adjusts the dosage of medication based on online monitoring data
Coupling design of waste heat boiler+dust removal and desulfurization, achieving a 30% reduction in energy consumption
Calcium based waste (such as carbide slag) replaces traditional desulfurizers
The current new lime kiln project needs to meet the "Emission Standards for Air Pollutants in the Lime Industry" (GB 29452-2019). It is recommended to prioritize the full process solution of "dust removal+desulfurization and denitrification+wet electricity" to ensure ultra-low emission requirements of particulate matter<10mg/Nm ³ and SO ₂<100mg/Nm ³.
