Landfill co-disposal of phenol-bearing wastewaters: organic load considerations

A multi-stage model, operated with single elution, was used to investigate the effects of organic loadings on the attenuation of a model phenolic wastewater in domestic refuse. Although 100% dissimilation of influent phenol (2-5 mmol dm-3) was recorded at a dilution rate of 0.007 h-1, partial inhibition of both phenol degradation and species competing with methanogens for a common electron donor(s) was apparent at concentrations greater than or equal to 4 mmol dm-3. On extended perfusion with 8 mmol phenol dm-3, the progressive inhibition of phenol dissimilation was not obviated by nutrient supplementation. Simultaneous degradation of the catabolic intermediate, hexanoic acid, and elevated methane release rates suggested that the transformation of phenol to hexanoate was rate limiting.