This course describes chemical leaching tests and biological assays to measure the sulfate content of a solid waste and to estimate its hydrogen sulfide production potential. A number of chemical leaching tests were compared to evaluate the most effective test to measure both sulfate and solid phase sulfide. In addition, both small (160 mL) batch reactors and larger 8-L reactor systems were evaluated to measure the rate and extent of sulfate conversion to hydrogen sulfide. Laboratory-measured first order decay constants were used to estimate decay rate constants applicable to MSW landfills. Recommended decay rates and hydrogen sulfide yields will be presented for 5 fly ash samples from coal combustion, two ash samples from MSW combustion, and C&D fines. Limitations of the laboratory tests will also be presented.
Upon completion of this course, the attendee will be able to:
- Become familiar with the types of waste that may contain sulfate and the limitations of various chemical test methods
- Learn methods to estimate the hydrogen sulfide production potential of a waste from chemical leaching data and from biological assays
- Understand the implications of sulfide toxicity on biological tests
- Develop an appreciation for the uncertainty in using a first model and decay rate constant to predict hydrogen sulfide production