Pilot study on demister-based dust removal methods for boiler flue gas

Area of Science:

• Environmental Engineering
• Air Pollution Control

Background:

• Boiler flue gas dust emissions pose environmental challenges.
• Achieving ultra-low emission standards requires efficient dust removal technologies.

Purpose of the Study:

• To evaluate the synergistic dust removal effects of demisters combined with other technologies.
• To identify cost-effective solutions for ultra-low emission reformation in industrial settings.

Main Methods:

• Pilot-scale experimental setup to test demisters alone and in combination with wet electrostatic precipitators and water-washing layers.
• Measurement of dust removal efficiency and outlet dust concentration under varying conditions.
• Analysis of the impact of inlet dust concentration and liquid-gas ratio (L/G).

Main Results:

• Demisters alone provided 28.43-51.30% dust removal efficiency, increasing with inlet concentration but failing to meet ultra-low standards.
• Simultaneous operation of wet electrostatic precipitator and demisters achieved 93.13% efficiency, with outlet dust < 5 mg/Nm³.
• The water-washing layer plus demisters achieved 70.98-78.37% efficiency, meeting the 10 mg/Nm³ standard at L/G > 3.5.

Conclusions:

• The "water-washing layer + demisters" method is a viable, cost-effective alternative to wet electrostatic precipitators for ultra-low emission reformation when inlet dust concentration is ≤ 35 mg/Nm³ and L/G ≥ 3.5.
• Synergistic combinations significantly enhance dust removal efficiency compared to demisters alone.
• Findings provide valuable insights for reducing construction costs in emission control projects.