Sampling and Analysis - Orlando
Sampling and Analysis
orange county solid waste management, orlando, florida
GSE conducted total gaseous non-methane organic carbon (TGNMOC) sampling and analysis from 6 landfill gas collection system header locations at an Orange County Landfill. US EPA Reference Method 25/25C(M25) was elected to measure methane (CH4), carbon dioxide (CO2), and TGNMOC from landfill gas samples. Moisture was measured in-situ using an Alnon relative humidity probe and by measuring the gas temperature and assumed saturation.
M25 was selected as the preferred method for the NMOC over method 25C for several reasons:
- M25 results in a more accurate TGNMOC value because it is unaffected by a sample matrix high in reduced sulfur compounds, CO2 and moisture that negatively affects M25C sensitivity. M25C has been shown to read up to a magnitude low when analyzing landfill gas due to the gas condensing onto the sample containers and the complex gas matrix.
- The condensable hydrocarbons (TGNMOC) portion of the landfill gas are captured in a cryogenic trap and analyzed separately from CO, CO2, and methane which get trapped in an evacuated stainless steel polished canister, as opposed to M25C that analyzes all compounds from a Tedlar bag mixture filled with helium.
- The TGNMOC portion of the samples do not have to be diluted with inert gas such as helium to reduce flammability since the samples will be hand-delivered to Newberry, Florida by the laboratory personnel who assisted in the sample collection.
- The analysis will be conducted within 24 hours or less from the time of sample collection.