2019 CSCE Annual Conference - Laval (Greater Montreal) Conference
Dr. Patrick Hettiaratchi, University of Calgary
The source and type of Inoculum plays an important role in BMP assays through adaptation to substrate and provision of the required microbial consortia required to effectively degrade landfilled municipal solid waste (LMSW). While biosolids from wastewater treatment plants have been the preferred choice for use in conventional BMP assays, studies have shown a potential for this source to be misrepresentative of the consortia of microbes required for the effective degradation of LMSW. Also, the conventional BMP assays often misrepresent typical landfill conditions in terms of moisture content and sample size. This study investigated the effects of inoculum source on methane generation of LMSW by comparing the performance of biosolids and a laboratory derived inoculum (LDI) using; a synthetic waste representing the organic fraction of municipal solid waste in solid-phase BMP conditions and cellulose in conventional slurry phase conditions respectively. Results showed a statistically significant superior performance of the LDI over biosolids in terms of methane generation potential, Lo, and lag-phases for both slurry-based and solid-based moisture conditions. However, the difference in rate of methane production (Rm) between both inocula was found to be statically insignificant when degrading cellulose only. The highest coefficient of variation between duplicates was found to be 23% indicating good repeatability of methods used and validity of results obtained.