Chemical Characteristics and Formation of Secondary Aerosol from Biomass Burning in an Open Chamber System

다국어 초록 (Multilingual Abstract)

Biomass burning refers to the combustion of organic materials and it is one of the largest emission sources originating from both natural and anthropogenic activities. This study focuses on two key points: chemical composition and characteristics of biomass burning emissions, and a method to estimate biomass burning organic aerosol by high-resolution time of flight aerosol mass spectrometer. The aim of this research is to improve the understanding of air pollution associated with biomass burning.
To investigate the characteristics of biomass burning emission, combustion experiments were conducted using an open burning chamber equipped with various analytical instruments. PM1 emissions were dominated by organic aerosol （OA）, followed by black carbon （BC）, and chloride （Cl-） showed variability depending on the biomass type. Major gaseous emissions were carbon dioxide （CO2） and carbon monoxide （CO）, followed by nitrogen oxides （NOX） and methane （CH4）. Among the volatile organic compounds （VOCs） emission, formaldehyde and acetaldehyde were the highest emitted components. Secondary aerosol formation was primarily associated with NO3- and OA.
In addition, HR-ToF-AMS data were used to develop a conversion factor for BBOA estimation. The factor was derived as 53.136 and showed good correlation with the BBOA derived from positive matrix factorization （PMF） evaluation toolkit （PET）, demonstrating its applicability for rapid estimation of biomass burning contributions in ambient measurements.
Overall, this study provides comprehensive emission factors, chemical characterization, and insights into secondary aerosol formation from biomass burning. The results contribute to improving emission inventories and understanding pollutant formation mechanisms. These findings have important implications for air quality modeling, source apportionment, and the assessment of biomass burning impacts on atmospheric chemistry and climate.

목차 (Table of Contents)

• Chapter I. Introduction 1
• 1. Biomass burning emissions 2
• 2. Biomass burning markers 5
• 3. References 8
• Chapter II. Emission characteristics and secondary aerosol formation from biomass burning in an open chamber system 16
• 1. Introduction 18
• 2. Methods 19
• 2.1. Measurements and Instrumentation 19
• 2.2. Biomass burning samples 27
• 2.3. Emission factors and modified combustion efficiency 29
• 2.4. Quality assurance and quality control (QA/QC) 31
• 3. Results and discussion 34
• 3.1. Chemical composition and characteristics of each fuel type 34
• 3.2. Secondary aerosol formation from biomass burning 61
• 4. Conclusion 65
• 5. References 67
• Chapter III. Evaluation of an HR-ToF-AMS biomass burning tracer for BBOA estimation: from open chamber experiments to ambient observations 76
• 1. Introduction 78
• 2. Methods 79
• 2.1. HR-ToF-AMS data analysis 79
• 2.2. Positive Matrix Factorization (PMF) analysis 82
• 3. Results and discussion 85
• 3.1. Biomass burning markers from open chamber experiments 85
• 3.2. Comparison of chamber and ambient observations 92
• 4. Conclusion 98
• 5. References 99
• Chapter IV. Conclusions 106
• LIST OF PUBLICATIONS 109