An arc profile-based approach to evaluate gas pollutants in welding

Area of Science:

• Environmental Science
• Industrial Engineering
• Materials Science

Background:

• Welding processes generate significant air pollution, including carbon dioxide (CO2), ozone (O3), nitrogen oxides (NOx), and particulate matter (PM).
• Accurate measurement of these gaseous pollutants is challenging due to their fluid and diffuse nature.
• Understanding pollutant generation is crucial for developing effective emission control strategies.

Purpose of the Study:

• To propose and validate an arc profile-based method for quantitatively evaluating gas pollutant emissions during welding.
• To investigate the relationship between welding parameters and pollutant generation.
• To support the development of sustainable manufacturing practices by minimizing welding-related environmental impact.

Main Methods:

• Utilized a high-speed camera to capture welding arc images.
• Employed binarization processing to extract and reconstruct the welding arc's edge and determine its coverage volume.
• Calculated gas pollutant emissions based on chemical reactions and arc discharge intensity.
• Conducted welding experiments to measure actual NOx and O3 concentrations.

Main Results:

• The proposed arc profile-based method provides a credible and feasible approach for quantifying welding emissions.
• Measured NOx and O3 concentrations were found to be 70% and 79%, respectively, of the calculated emissions.
• Investigated the influence of welding time, current, and arc length on gas pollutant generation.

Conclusions:

• The arc profile-based method offers a reliable way to quantitatively assess welding-related air pollution.
• The study provides insights into controlling welding parameters to reduce environmental impact.
• This research contributes to advancing sustainable manufacturing through better emission management in welding operations.