Factors Affecting Mercury Control in Utility Flue Gas Using Activated Carbon

Area of Science:

• Environmental Engineering
• Chemical Engineering
• Air Pollution Control

Background:

• Utility flue gas contains mercury, a hazardous air pollutant.
• Effective mercury removal technologies are crucial for environmental compliance.
• Sorbents are being investigated for their potential in mercury capture.

Purpose of the Study:

• To investigate mercury removal from utility flue gas using various sorbents.
• To determine the influence of sorbent type, flue gas parameters, and temperature on mercury adsorption.
• To develop a theoretical model for predicting mercury removal efficiency.

Main Methods:

• Conducted bench-scale and pilot-scale tests using simulated and actual flue gas.
• Investigated parametric effects on sorbent performance, focusing on activated carbon.
• Studied the removal of mercuric chloride and elemental mercury.

Main Results:

• Sorbent adsorption capacity is significantly influenced by the mercury species (e.g., mercuric chloride vs. elemental mercury).
• Flue gas composition and adsorption temperature are critical factors affecting mercury removal efficiency.
• Preliminary data suggest both physical and chemical adsorption mechanisms are involved in mercury removal.

Conclusions:

• Mercury removal by sorbents is a complex process dependent on multiple variables.
• Sorbent performance can vary significantly across different sites due to site-specific flue gas matrices.
• Further research is needed to refine theoretical models and optimize sorbent selection for mercury control.