SUMMARY The objective was to study the viability of methane production through the utilization of whey from cheese manufacture and, also, to evaluate the behaviour of methanogenic bacteria. Biodigestors were FED with cheese whey (proportions of 1%, 5% and 10% of the nominal volume), and mantained at 35° C. Five retention times and four feeding systems were used for different times of substract addition. In the first and second retention times, biodigestors were FED at intervals of 24 hours. In the third retention time, the load was dividid in three parts and put into biodigestors every eight hours. In the fourth retention time, biodigestors received 8 feeding daily, at regular intervals of 2 hours. For the fifth retention time, the organic load was divided in to five daily feeding that were put into biodigestors at intervals of 3 hours and 36 minutes. Results of this work showed that the anaerobic conditions were affected by the feeding systems of biodigestors, but it was possible to treat the residues from dairy plants, since as cheese whey, by using anaerobic digestion with production of biogas. The maximum methane production was obtained at the 5% concentration and three daily feedings system, althought, there was not a statisticaly significative difference among the feedings systems.
biodigestors; anaerobic digestion; retention times; production of methane; cheese whey