A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science of the Asian Institute of Technology, Bangkok, Thailand.

Thesis (M.Sc.) - Asian Institute of Technology, 1976

This research is an anaerobic kinetic study of an industrial concentrate organic soluble waste from Pepsi-Cola Bottling Plant. The study covered two different phases, one was the batch process, and the other was semi-continuous flow process. Temperature, which has a profound effect in kinetic constants determination, was kept constant at 30°C throughout the study. The batch process, a rather new approach in anaerobic kinetic study, was composed of six units of different initial COD ranging from 420 mg/l to 3280 mg/l. The results showed that exponential growth did occur even when substrate was not present in excess, although almost all the exponential growth last only for 3 hours and terminated before the twelveth hour. A æm value of 0.1089 hr-1 and a K8æ of 200 mg COD/l was obtained in this part of the study. Final COD removal, which was rather consistent, varied from 83-92%. In the semi-continuous flow process, loading at 0.57 Kg COD/ID3/day (HRT = 16.67 days) gave the highest COD removal of 75.8% and loading at 1.33 Kg COD/rrf3/day (HRT = 7.14 days) had the lowest COD removal of 42.8%. The kinetic constants evaluated can be summarized as follow: Maximum Specific Utilization Rate k = 0.4909 day-1 Half Velocity Coefficient (when U =1/2k) Ks = 2049 mg COD/1 Growth Yield Coefficient a = 0.7475 mg VSS/mg COD Microorganism Decay Coefficient b = 0.1369 day-1 Maximum Specific Growth Rate æm = 1.190 day-1 Saturation Coefficient (when æ = æm/2) K8æ = 42980 mg COD/1 All these kinetic constants obtained are valuable in the design of treatment plant for treating the waste involved in this study. Further evaluation of these constants and mathematical model employed showed that the experimental and theoretical effluent qualities, as well as volatile suspended solids concentrations, were representable of each other.