Anaerobic treatment of pre-settled cosmetic wastewater in batch and continuous experiments has been
investigated. Biodegradability tests showed high COD and solid removal efficiencies (about 70%), being
the hydrolysis of solids the limiting step of the process. Continuous treatment was carried out in an
upflow anaerobic sludge blanket reactor. High COD and TSS removal efficiencies (up to 95% and 85%,
respectively) were achieved over a wide range of organic load rate (from 1.8 to 9.2 g TCODL−1 day−1).
Methanogenesis inhibition was observed in batch assays, which can be predicted by means of a Haldanebased
inhibition model. Both COD and solid removal were modelled by Monod and pseudo-first order
models, respectively.