INFLUENCE OF THE SUPPORT ON THE KINETICS OF ANAEROBIC PURIFICATION OF SLAUGHTERHOUSE WASTE-WATER

Three materials of different composition, sepiolite, saponite and bentonite, assayed as supports for the micro-organisms effecting anaerobic fermentation, were found to behave differently towards slaughterhouse wastewater from a kinetic point of view. Assuming the overall anaerobic digestion process to conform to first-order kinetics, the apparent kinetic constant for the digester including bentonite as support was 1.28 per day, while that of the digesters using the sepiolite and saponite were 0.83 and 0.56 per day, respectively. Thus, the support used to immobilize the micro-organisms that mediate the process had a marked influence on the constant. This was found to be significant at 95% confidence level The yield coefficient, Y(p), was 343, 334 and 349 ml CH4 STP per g COD added for the sepiolite, saponite and bentonite, respectively.