Food Engineering logo
  • Sign In
  • Create Account
  • Sign Out
  • My Account
  • NEWS
  • PRODUCTS
  • TOPICS
  • EXCLUSIVES
  • MEDIA
  • FOOD MASTER
  • EVENTS
  • RESOURCES
  • EMAGAZINE
  • SIGN UP!
cart
facebook twitter linkedin youtube
  • NEWS
  • Latest Headlines
  • Manufacturing News
  • People & Industry News
  • Plant Openings
  • Recalls
  • Regulatory Watch
  • Supplier News
  • PRODUCTS
  • New Plant Products
  • New Retail Products
  • TOPICS
  • Alternative Protein
  • Automation
  • Cannabis
  • Cleaning | Sanitation
  • Fabulous Food Plants
  • Food Safety
  • Maintenance Strategies
  • OEE
  • Packaging
  • Sustainability
  • More
  • EXCLUSIVES
  • Plant Construction Survey
  • Plant of the Year
  • Sustainable Plant of the Year
  • State of Food Manufacturing
  • Top 100 Food & Beverage Companies
  • MEDIA
  • Podcasts
  • Videos
  • Webinars
  • White Papers
  • EVENTS
  • Food Automation & Manufacturing Symposium and Expo
  • Industry Events
  • RESOURCES
  • eNewsletter
  • Custom Content & Marketing Services
  • FE Store
  • Government Links
  • Industry Associations
  • Market Research
  • Classified Ads
  • EMAGAZINE
  • eMagazine
  • Archive Issue
  • Advertise
Food Engineering logo
search
cart
facebook twitter linkedin youtube
  • Sign In
  • Create Account
  • Sign Out
  • My Account
Food Engineering logo
  • NEWS
    • Latest Headlines
    • Manufacturing News
    • People & Industry News
    • Plant Openings
    • Recalls
    • Regulatory Watch
    • Supplier News
  • PRODUCTS
    • New Plant Products
    • New Retail Products
  • TOPICS
    • Alternative Protein
    • Automation
    • Cannabis
    • Cleaning | Sanitation
    • Fabulous Food Plants
    • Food Safety
    • Maintenance Strategies
    • OEE
    • Packaging
    • Sustainability
    • More
  • EXCLUSIVES
    • Plant Construction Survey
    • Plant of the Year
    • Sustainable Plant of the Year
    • State of Food Manufacturing
    • Top 100 Food & Beverage Companies
  • MEDIA
    • Podcasts
    • Videos
    • Webinars
    • White Papers
  • FOOD MASTER
  • EVENTS
    • Food Automation & Manufacturing Symposium and Expo
    • Industry Events
  • RESOURCES
    • eNewsletter
    • Custom Content & Marketing Services
    • FE Store
    • Government Links
    • Industry Associations
    • Market Research
    • Classified Ads
  • EMAGAZINE
    • eMagazine
    • Archive Issue
    • Advertise
  • SIGN UP!

Engineering R&D: Biotrickling reduces bakery ethanol emissions by 85-100 percent

March 26, 2003
A four-month pilot study conducted at the Interstate Brands Wonderbread Bakery in Columbus, OH concluded that a two-stage biotrickling filter composed of environmentally-available bacteria immobilized on solid polypropylene fibers reduced ethanol emissions by 85 to 100 percent. As shown on the table on page 28, the system averaged 91 percent ethanol-removal efficiency during the study period, excluding filter downtime.

The project was funded by the EPA, USDA, the Lincoln Food Processing Center at the University of Nebraska and the American Bakers Association (ABA). The EPA supplied the trailer-mounted biofiltration unit, designed by PRD Tech, Inc. and incorporating proprietary PRD support media. PRD Tech worked with with the department of chemical engineering at the University of Cincinnati to conduct the study. Malcolm Pirnie, Inc. (Columbus, OH) designed and installed the duct work connecting the oven-stack to the biofilter.

The Food Manufacturing Coalition (FMC) for Innovation & Technology Transfer functioned as project manager via R. J. Phillips & Associates (Sterling, VA). Composed of eight food industry associations plus private firms, government entities and universities, the FMC is assessing opportunities for technology transfer to other food industry segments.

Results of the pilot study were presented by Dr. Rakesh Govind, professor of chemical engineering at The University of Cincinnati and director of PRD Tech, at the annual meeting of the American Institute of Chemical Engineers (AIChE) November 19 in Miami Beach. "Not only has this system proven to significantly reduce ethanol emissions, it can be significantly more cost efficient than currently-available technologies," Govind reported.



Biofilter drawbacks

Ethanol, a byproduct of fermentation, is a volatile organic compound (VOC). Through a complex interaction with sunlight and nitrogen oxides, ethanol and other VOCs contribute to the formation of ground-level ozone that can potentially have an adverse impact on human health and the environment. Roughly 98 percent of the VOCs produced in bakery ovens are ethanol.

The most common approach to reducing ethanol emissions is to treat them with biofilters, where bacteria degrade or transform the contaminants. Biofilters typically use peat or compost to sustain the microbial populations. But because the concentration of ethanol emissions varies with production schedule and with product (bread, pastry, cake etc.), bacteria growth can be uneven: overproduction clogs filters; underutilization starves the bacteria. Moreover, because bacteria consume the biofilter material, it must regularly be replaced. These systems can also be "extremely bulky," said Govind. Where space is at a premium, the system must often be located on rooftops, requiring structural modifications to support the load and thus adding capital cost.



Biotrickling benefits

Biotrickling, Govind explained, improves upon biofiltration. In biotrickling, a recycled water/nutrient stream distributes nutrients (such as phosphorous and nitrogen) to the bacteria and keeps the filter moist. Because the support housing the microbes is made of synthetic materials, and because the nutrients are trickled-in, the support media are not degraded and can last indefinitely. The system uses environmentally-available bacteria and no special strains are needed. The filter is self-cleaning, so bacteria cannot clog it with unlimited growth. Because the system is at the end of the baking operation, the microbes cannot contaminate the baked goods. While microbes thrive in the ambient exhaust temperatures, they cannot survive the high temperatures of upstream gases (more than 350° F).

Although ethanol concentrations vary with product, the biotrickling filter maintained removal efficiencies exceeding 80 percent for 99.6 percent of its operating time -- even when the ethanol concentration was abruptly increased. During shutdown periods, however, the microbial decay rate was slow, enabling the biofilter to regain more than 95 percent removal efficiency in just a few hours. Because there are no supplemental fuel requirements or catalyst replacements (as with catalytic oxidizers), biotrickling can save operating costs. Furthermore, the system operates at ambient temperatures and pressure, emits no nitrogen oxides and emits less CO2. "There are no downsides to this technology," Govind observed.

The pilot study provides a plus- or-minus 30 percent estimate of capital and operating costs for a biotrickling filter applied to treating ethanol emissions from bakeries. More precise estimates can be calculated only after a system has been designed for a specific plant.

Biotrickling can potentially be adapted to other fermentation processes such as brewing, Govind added. The FMC licenses the technology.

Share This Story

Looking for a reprint of this article?
From high-res PDFs to custom plaques, order your copy today!

Recommended Content

JOIN TODAY
to unlock your recommendations.

Already have an account? Sign In

  • Global Organic Food & Beverage Market to Grow

    Global Organic Food & Beverage Market to Grow

    With a CAGR of 12.07%, Bonafide Research estimates this...
    People & Industry News
  • skilled MEP worker

    Predicting Food and Beverage Manufacturing Trends for 2024

    The two words that should be kept in mind are labor and...
    Automation
    By: Derrick Teal
  • cleaning and sanitation

    The basics of cleaning and sanitation in food plants

    Sanitation maintains or restores a state of cleanliness...
    Cleaning | Sanitation
    By: Richard F. Stier
Manage My Account
  • eMagazine
  • eNewsletter
  • Online Registration
  • Manage My Preferences
  • Customer Service

Food Plant Openings and Expansions June 2025

Food Plant Openings and Expansions June 2025

Celebrating Women in Engineering: Shalima Sreenath

Celebrating Women in Engineering: Shalima Sreenath

Celebrating Women in Engineering: Samara Heaggans

Celebrating Women in Engineering: Samara Heaggans

Food Plant Openings and Expansions May 2025

Food Plant Openings and Expansions May 2025

More Videos

Popular Stories

Cargill Cocoa Plant

Cargill Invests in its Cocoa Supply Chain

Campbell’s Utah plant

Going for Gold(fish): Inside The Campbell’s Company’s $160M Cracker Plant Expansion

Woman engineer on construction site

Exploring the Impact of Women Engineers on the Food Industry

CHECK OUT OUR NEW ESSENTIAL TOPICS

Alternative ProteinAutomationCleaning/SanitationFabulous Food Plants

Food SafetyMaintenance StrategiesOEE

PackagingSustainability

Events

June 17, 2025

Refrigerated & Frozen Foods’ State of the Cold Chain

On Demand Kelley Rodriguez, Editor in Chief of Refrigerated & Frozen Foods, will be joined in this 60-minute webinar by industry experts to help unpack the latest research.

July 23, 2025

Decarbonizing Process Heat: What You Should Know and Next Steps

Driven by climate goals, business risk, client interest, and resilience considerations, food and beverage companies are increasingly turning their attention to decarbonizing their production processes.

View All Submit An Event

Products

Recent Advances in Ready-to-Eat Food Technology

Recent Advances in Ready-to-Eat Food Technology

See More Products

Plant of the Year

Related Articles

  • Engineering R&D: Temperature readings by remote control

    See More
  • Impingement Reduces Cook Time by 88 Percent

    See More
  • Blender Reduces Waste by 80 Percent

    See More

Related Products

See More Products
  • military-food-engineering.gif

    Military Food Engineering and Ration Technology

  • handbookfoodscience.jpg

    Handbook of Food Science and Technology 2: Food Process Engineering and Packaging

  • Food-Authentication-Flyer-(.gif

    Food Authentication Using Bioorganic Molecules

See More Products
×

Elevate your expertise in food engineering with unparalleled insights and connections.

Get the latest industry updates tailored your way.

JOIN TODAY!
  • RESOURCES
    • Advertise
    • Contact Us
    • Food Master
    • Store
    • Want More
  • SIGN UP TODAY
    • Create Account
    • eMagazine
    • eNewsletter
    • Customer Service
    • Manage Preferences
  • SERVICES
    • Marketing Services
    • Reprints
    • Market Research
    • List Rental
    • Survey/Respondent Access
  • STAY CONNECTED
    • LinkedIn
    • Facebook
    • YouTube
    • X (Twitter)
  • PRIVACY
    • PRIVACY POLICY
    • TERMS & CONDITIONS
    • DO NOT SELL MY PERSONAL INFORMATION
    • PRIVACY REQUEST
    • ACCESSIBILITY

Copyright ©2025. All Rights Reserved BNP Media.

Design, CMS, Hosting & Web Development :: ePublishing

Food Engineering logo
search
cart
facebook twitter linkedin youtube
  • Sign In
  • Create Account
  • Sign Out
  • My Account
Food Engineering logo
  • NEWS
    • Latest Headlines
    • Manufacturing News
    • People & Industry News
    • Plant Openings
    • Recalls
    • Regulatory Watch
    • Supplier News
  • PRODUCTS
    • New Plant Products
    • New Retail Products
  • TOPICS
    • Alternative Protein
    • Automation
    • Cannabis
    • Cleaning | Sanitation
    • Fabulous Food Plants
    • Food Safety
    • Maintenance Strategies
    • OEE
    • Packaging
    • Sustainability
    • More
  • EXCLUSIVES
    • Plant Construction Survey
    • Plant of the Year
    • Sustainable Plant of the Year
    • State of Food Manufacturing
    • Top 100 Food & Beverage Companies
  • MEDIA
    • Podcasts
    • Videos
    • Webinars
    • White Papers
  • FOOD MASTER
  • EVENTS
    • Food Automation & Manufacturing Symposium and Expo
    • Industry Events
  • RESOURCES
    • eNewsletter
    • Custom Content & Marketing Services
    • FE Store
    • Government Links
    • Industry Associations
    • Market Research
    • Classified Ads
  • EMAGAZINE
    • eMagazine
    • Archive Issue
    • Advertise
  • SIGN UP!