Issue link: https://read.dmtmag.com/i/1535695
30 STiR coffee and tea | 2025 Quarter 2 Summer (Jun/jul/Aug) Clean Roasting Emissions with Electrostatic Precipitation C By Bhavi Patel offee roasting is an essential step for converting green beans into the aromatic and flavorful coffee that every- one loves. However, roasting also carries a significant environmental burden beyond simple energy consumption. The process releases particulate matter, volatile organic compounds (VOCs), and various organic pollutants into the atmosphere, contributing to local air quality issues and broader environmen- tal concerns. These emissions primarily stem from complex chemical reactions during roasting, where compounds within the green coffee beans break down and transform at high temperatures, releasing smoke, chaff, and aromatic compounds. Additionally, traditional gas-powered roasters contribute to carbon dioxide emissions through fossil fuel consumption, while inadequate fil- tration systems allow pollutants to escape into the surrounding environment. As the coffee industry continues to grow and consumers become more environmentally conscious, finding effective so- lutions to minimize these emissions has become not just an en- vironmental imperative but also a business necessity for roasting operations of all sizes. Electrostatic precipitation (ESP) filters are both efficacious and energy efficient, and just might be the sustainable answer coffee roasters are searching for. The coffee roasting process generates oil fumes and odor, made of fatty acids and volatile compounds. These harmful pollutants need to be filtered out of the exhaust in order for roasting establishments to achieve zero emissions. An electrostatic precipitation (ESP) air filtration system is more energy-efficient and effective than afterburners or cyclones. Photo courtesy Zoshua Colah Electrostatic Precipitation (ESP) Filter Multi-Layer Mesh Filter Pre-filter Activated Carbon Filter Odor Removal Tubular Filter Cells Particulates Collection ESP filters create an electrical field that ionizes airborne particles from the roasting process, giving them a negative charge. As these charged particles pass through the filter, they are strongly attracted to positively charged collection plates, effectively removing them from the exhaust stream. Infograph courtesy Kleanland