DETERMINATION OF KINETIC PARAMETERS OF AN UPFLOW ANAEROBIC SLUDGE BLANKET REACTOR (UASB), TREATING SWINE WASTEWATER

This research aimed to estimate the kinetic parameters of a UASB reactor treating swine wastewater from farming. The system consisted of: a degritter with a triangular-notch weir in order to measure the flow; a static sieve; an acidification/equalization tank (AET); ABR and UASB reactors; a settling tank; two infiltration ponds and a greenhouse for fertirrigation. The hydraulic retention times (HRT) adopted for the UASB reactor, were: 8.0; 9.6; 8.4; 6.0 and 4.8 hours. The operational temperature was 23.4 degrees C+1.5 degrees C. The analyzed physical-chemical parameters were temperature COD (total and filtered), BOD (total and filtered), total volatile solids (affluent, effluent and of the reactor's profile sludge), flow rate and nutrients (N and P). The kinetic coefficients estimated were: growth coefficient Y=0.091 mg tCOD mg TVS-1.d(-1), decay coefficient K-d = 0.01 d(-1); concentration of limiting substrate K-s = 282.5 tCOD mg L-1 and maximum growth rate mu(max) = 0.051 d(-1). For data validation, simple linear regression models were applied and their interaction verified with a "t" test. The results matched with the those found in other references for the same type of kinetic studies.