Biogas that was produced in the CSTRs flowed through
calibrated Ritter wet test meters that continuously measured the
biogas production. The amount of gas produced was recorded daily
to understand the impact of crude glycerol on the co-digestion.
Weekly gas analysis was performed to ascertain the methane content
in the biogas, which was expected to vary with crude glycerol
loading and primary composition. Due to variations in primary
composition, the primary was subtracted from primary and
glycerol to understand the contributions of glycerol alone as
shown in Fig. 2. Gas analysis was done using a Perkin Elmer Clarus
600 Gas Chromatograph equipped with Perkin Elmer Elite-PLOT Q
column and a Thermal Conductivity Detector. Reactor health is
defined by key variables that determine stable operating