Strategic Materials Inc.: Crushing Dust and Odor Issues in Glass Recycling

Crushing Dust and Odor Issues in Glass Recycling
Strategic Materials, Inc. (SMI) is North America’s largest and oldest glass recycling company, beginning life in 1896. Today, they recycle nearly three million tons of glass each year. SMI contacted RoboVent to help address airborne dust and odor challenges at the company’s glass recycling facility in Wisconsin. RoboVent designed a holistic air filtration and ventilation solution that incorporates both source capture and ambient filtration, along with odor control, to create an improved working environment and improved community relations.

The Problem
SMI accepts glass from a variety of recycling streams, including curbside, single-stream collection and commercial collections, turning it into a valuable material that is used by manufacturers to make products like new glass containers and fiberglass insulation. Each day, large trucks bring tons of glass to the loading docks. From there, the glass is crushed, screened and color-sorted into furnace-ready, recycled glass called cullet. The crushing process can naturally create glass dust, including coarse particulate and respirable “fines” that remain suspended in the air. Organics from food and beverage containers, along with other non-glass materials received in the glass pile, contribute to odor challenges, both inside the facility and on the property.

SMI’s previously installed cyclone and baghouse source capture systems collected a certain level of heavy dust but did not fully prevent fines from propagating through the facility. While SMI remained OSHA compliant, it was a priority for the company to improve indoor air quality to enhance employee comfort, ensure good community relations, and continue leadership in environmental stewardship.

The RoboVent Solution
RoboVent engineers completed an analysis of dust-producing processes and dust levels throughout the facility. The team performed a VentMapping study to analyze airflow patterns, point emission sources and existing ventilation and source capture equipment. VentMapping uses Computational Fluid Dynamics (CFD) to visualize airflow and optimize the placement of source capture, ambient air filtration and ventilation components.

The resulting solution took advantage of existing baghouse and cyclone dust collection equipment to capture coarse dust from point sources and added several large cartridge-style dust collectors to capture the remaining fines. These source capture solutions were combined with an ambient push-pull system to pull fine dust out of the air at ceiling level and several ambient Vortex™ units to break up dust clouds at lower elevations. Activated charcoal after-filters were added to the dust collectors to control odor; the facility is kept at negative pressure to ensure that odors do not escape through open garage bay doors. The holistic solution also incorporates stack ventilation, a makeup air system and HVAC elements to maintain a comfortable working temperature for people and equipment.

The Result
Since implementing the RoboVent solution, the glass recycling facility has seen a five-fold decrease in ambient dust particles in the air. Best of all, they have already seen an increase in employee retention.

There has also been a noticeable decrease in odor. The activated carbon filtration and stack ventilation ensure that there is little or no odor at the perimeter of their property, and they have had zero complaints or citations from the community since RoboVent installed the filtration system. A comprehensive dust and odor control solution has made a world of difference in alignment with the company’s purpose to recycle glass and unite the interests of people, partners and the planet. RoboVent provided the support to improve employee comfort, neighbor satisfaction and environmental health.