NOVELTY - Bacterial composition for degradation of pasty sludge heavily filled with animal fat comprises a combination of bacterial strains containing a bacterial strain e.g. Pseudomonas, Shewanella, Morganella, Myroides or Citrobacter.    USE - The composition is useful to treat the animal fat sludge coming from agro-food industry and effluents produced by local community (claimed), particularly for wastewater treatment.    ADVANTAGE - The composition makes the process simple, easy and inexpensive with effective elimination fat.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for:    (1) a process of treating pasty sludge filled with animal fat comprises transporting the filtered pasty sludge into the tank (2) of a bioreactor (3), where the composition is introduced, filtering the pasty sludge for separating the fatty waste to be treated from other unwanted particles, maintaining a homogenization and oxygenation of the medium inside the bioreactor tank, maintaining the sludge ( approximately 25 wt.%) at 35degreesC, resting the sludge inside the bioreactor for 4-5 days per m3; and    (2) an assembly for the given process comprising the bioreactor equipped with the tank containing the composition, the feeding device (1) in which inside the tank of sludge filled with matter of predetermined size, the bioreactor is equipped with device for a sludge agitator, an oxygenation device (10) for sludge by supplying gas, thermal device for maintaining sludge at a room temperature, measuring device (12) of any of the physicochemical parameters of sludge treated in the bioreactor comprising the temperature, pH and redox potential, and the level of sludge inside the tank, circulation device of sludge located between a filtration device and the tank, and an evacuation device to remove the treated sludge from the bioreactor.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic representation of the sludge treatment.    Feeding device (1)    Bio-composition containing tank (2)    Bioreactor (3)    Oxygenation device (10)    Physicochemical parameters-measuring device (12)