Particulate matter and gaseous emission rate from combustion of Thai lignite and agricultural residues in a fixed-bed combustor

ABSTRACT

This research has been conducted in order to obtain a database of emission rate of particulate matter and gases (CO, NO, and SO₂) from combustion of lignite and agricultural residues, such as rice husk. The experimental investigation was performed in a fixed-bed combustor. Thirteen stages–electrical low-pressure impactor was used to collect particles ranging in sizes from 40 nm to 10 μm. The results show that emission rate of total mass of particulate matter from combustion of rice husk is lower than that of lignite combustion but the total number of particles emitted is higher. This implies lower particle density from agricultural residue combustion. For co-firing lignite and rice husk, particulate matter emission is found to be higher than combustion of either lignite or rice husk and an increase in rice husk mass fraction in fuel mixture leads to an increase in particulate matter emission. From these quantitative data, it could be mentioned that the fuel characteristics influenced directly on particulate emission. For gaseous emission factors, CO and NO_x concentration decrease as SA/TA ratio increases. Meanwhile, SO₂ emission tends to increase. Both NO_x and SO₂ emissions are reduced as increased rice husk mass fraction in fuel mixture.

KEYWORDS:

• Combustion
• emission rate
• fixed-bed
• lignite
• particulate matter
• rice husk

Acknowledgment

The authors gratefully acknowledge the technical support of the Department of Mechanical Engineering at King Mongkut’s University of Technology North Bangkok.

Funding

Financial support for this research was provided by the Joint Graduate School of Energy and Environment (JGSEE).

Additional information

Funding

Financial support for this research was provided by the Joint Graduate School of Energy and Environment (JGSEE).