Biodegradation of Fat, Oil, and Grease (FOG) in Wet Wells

  • Author / Creator
    Fan, Gaoteng
  • Fat, oil, and grease (FOG) in wastewater can cause foul odor, sewer line blockage, and may interfere with sewage treatment. FOG control is approached with physical, chemical, and biological methods Many cities, including Edmonton, Alberta, Canada, have effectively applied commercial biological products to control FOG. Analysis of samples collected from wet wells in Edmonton was undertaken to examine the factors that influence the FOG control performance of commercial biological products. Field sampling showed a seasonal variation of FOG and COD concentrations indicating that the higher temperature in the summer-autumn term compared to the winter-spring term benefited FOG removal. The lowest FOG concentration (49.3 mg/L) was observed when the products were applied with a mixer on in summer-autumn term, which suggests the importance of oxygen and thorough mixing. Based on the results of wet well sample analyses, bench-scale experiments investigated the impacts on FOG removal of product dosage, initial COD, and temperature. Addition of 1000 times the recommended dosage of the commercial products increased FOG removal from 35.5% (achieved at the recommended dosage) to 41.1% in 14 days with an initial COD of 600 mg/L in 14 days. FOG removal increased from 29.8% to 48.0% with an increase in temperature from 15 °C to 32 °C. Suggestions to improve FOG control with commercial biological product application are proposed.

  • Subjects / Keywords
  • Graduation date
    Fall 2014
  • Type of Item
  • Degree
    Master of Science
  • DOI
  • License
    This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.