Characterization Of The Solid And Liquid Fractions Obtained By In Situ Separation Of Feces And Urine In Fattening Pig Facility

One of the challenges for the intensive farming is to avoid the environmental impact of the livestock farms. For the particular case of pig slurry, there are different strategies to minimize this impact. One of those strategies is the in situ separation of faeces and urine, obtaining by this way a solid fraction (SF) and a liquid fraction (LF), less contaminants and easier to handle. Already described the separation efficiency of faeces and urine using the system of inclined flat belts under slat belonging to the Pig Welfare Laboratory (E. T. S. Ing. Agronomos-Universidad Politecnica de Madrid, Spain), so the objective of this study was the characterization of those fractions produced in two rooms that differed in the type of continuous floor (concrete floor or concrete covered with epoxy resin). During a five weeks period time, faeces, urine, SF and LF collected were analysed. Of the different variables studied, only the dry matter (DM) of the SF and the total nitrogen and NH3-N contents and biochemical oxygen demand (BOD) of the LF were affected significantly by the room: the DM of the SF was significantly lower (255.4 vs 276.0 g.kg(-1), p = 0.0463) and the total nitrogen and NH3-N contents and BOD of the LF were significantly higher (4.8 vs 38 g.kg(-1), p = 0.0083; 4.2 vs 3.3 g.kg-(1), p = 0.0143; 231 vs 196 mg.L-1, p = 0.0072, respectively) for room with continuous floor covered with epoxy resin than for room with concrete floor, although the results are explained by the waste of water and not by the type of floor. Regardless of the room, the liquid fractions had pH values and NH3-N contents and the ratio 'NH3-N/ total N' higher than the urines.