Wastewater from a dairy processor is being reused and recycled both within the plant and for irrigation.
Flash pyrolysis GC–MS was used to examine nitrogen and phenol containing compounds (M.W. = 35 to
450 g/mol) in the particulate fraction of the milk condensate, combined clean wastewater and aerobic
bioreactor effluent. For comparison, the particulates were also prepared for standard GC–MS analyses
using conventional solvent extraction methods.
Compounds detected by pyrolysis GC–MS were foundmostly in the bioreactor with the amino acid argi-
nine (220 mg/kg) and the amino acid derivative 1-methyl-5-oxo-L-proline methyl ester (130 mg/kg)
found at the highest concentrations. In comparison, sterols detected in the effluent were found at higher
concentrations when using solvent extraction indicating some degradation with pyrolysis GC–MS.
However, with few exceptions, particulates were generally found not to act as passive collectors capable
of concentrating less water soluble chemicals.