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Updated: Jul 19, 2026
15:19
Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor
Published on: October 15, 2015
Generation pattern of sulfur containing gases from anaerobically digested sludge cakes
John T Novak1, Gregory Adams, Yen-Chih Chen
1Virginia Polytechnic Institute and State University, Blacksburg 24061, USA. jtnov@vt.edu
Summary
Odor-causing volatile sulfur compounds in dewatered sludge cakes from anaerobic digesters vary uniquely per sample. Production peaks within days, then declines due to organic sulfur conversion, but odor potential remains.
Area of Science:
- Environmental Science
- Environmental Chemistry
- Waste Management
Background:
- Anaerobic digestion is a common wastewater treatment process.
- Dewatered sludge cakes can produce significant odors.
- Understanding the composition and production of odorous compounds is crucial for effective odor management.
Purpose of the Study:
- To quantify and characterize the odorous gas production from dewatered sludge cakes.
- To identify the primary odor-causing chemicals and their production patterns.
- To assess whether anaerobic digestion eliminates the odor potential of sludge cakes.
Main Methods:
- Collection of eleven dewatered sludge cake samples from various anaerobic digesters (mesophilic and thermophilic).
- Analysis of the amount, type, and pattern of odorous gas production.
- Identification of key odor-causing volatile sulfur compounds (VSCs) such as hydrogen sulfide, methanethiol, and dimethyl sulfide.
Main Results:
- Each sludge cake sample exhibited unique patterns and quantities of sulfur gas production.
- Volatile sulfur compounds were identified as the primary odor contributors.
- VSC production peaked between 3 to 8 days post-collection, followed by a decline attributed to the conversion of organic sulfur to sulfide.
Conclusions:
- Anaerobic digestion does not fully eliminate the odor potential of dewatered sludge cakes.
- The characteristics of odorous gas production are sample-specific.
- Sludge dewatering methods, such as high-solids centrifugation, can influence the generation of odorous compounds.
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