Development of Low-Cost Dust Generation Chamber and Wireless Nephelometers for a Feedlot Dust Study

摘要

The development, testing, and calibration of a new dust sensor require a controlled dust generating environment. A low cost, safe, and easily customizable dust generating system that uses only COTS (commercial off-the-shelf) parts was developed as anintegral part of a feedlot dust study. The developed system is a dust generation and sampling chamber for testing wireless nephelometers. The system can generate suspended dust/air mixture with a high degree of density variations. The testing sensors areplaced inside the sampling chamber from which the measurement data is wirelessly transmitted to a recording console, providing a safe testing environment. This system uses a kitchen blender to generate dust and controls the concentration through an adjustable dust feedline, an intake airflow valve, and vacuum control valve. A shop vacuum controls the airflow rate through the dust chamber and collects the dust onto a filter. The objective of this project was to develop low-cost, miniaturized, wireless nephelometers to study PM1O concentration of a feedlot under various environmental and weather conditions. The apparatus, theory of operation, construction steps, and experimental results of the dust chamber and wireless nephelometers are presented.