Acclimation of mesophilic anaerobic sludge to thermophilic conditions: PCR genera detection methodology

In Mexico, sludge from wastewater treatment plants is a public health problem, especially for the infant population due to the presence of pathogens and parasite eggs. Therefore, it is of great interest to apply proper treatment methods for those wastes. An option proposed for the removal of possible infectious sources is thermophilic anaerobic digestion, even though a limitation for its acceptance is the slow start-up of the reactors. The transformation of a mesophilic anaerobic sludge for its utilization as a thermophilic inoculum, by means of direct temperature increase up to 55 degrees C and feeding of the inoculum with synthetic medium was possible in two months. As a main part of the work and with the objective of evaluating the changes in the methanogenic microbial population during the sludge treatment, a specific detection technique for these bacteria has been developed and validated, based on the use of the polymerase chain reaction (PCR).