| Abstract | Using Pepsi-Cola waste the effects of pH and areal COD loading on the performance of 3-stage anaerobic ponds in series were evaluated. The two
independent variables studied were at two levels ; pH was maintained in the 1st stage pond at about 8.5 and just below 6, and the areal COD loadings
applied were in the range of 8,500 to 12,000 and 30,000 to 50,000 lb/acre day. Another variable involved was detention time which was constant at 0.2 days in the 1st stage ponds. The main 9ependent variable measured was effluent COD but other parameters such as influent and effluent BOD5 ,
alkalinity, suspended solids, volatile suspended solids and volatile acids were measured gas production from 1st stage ponds and its composition
were determined. The results revealed that with COD loading in the range of 8,500 to 50,000 lb/acre day and at detention times from 0.1 to 0.2 days, pond pH level at and above 8.3 or at and below 6.1 resulted in a serious drop in COD, removal efficiency in any stage of pond with increasing COD loading.
Areal COD removal increased with increasing COD loading within the optimum pH range of less than 8.3 to more than 6.1 in all pond stages. COD removal
efficiency was highest in 1st stage ponds second highest in 2nd stage pond and lowest in 3rd stage ponds at any particular COD loading, provided
that pH in all ponds was within the optimum range. Gas production or composition in anaerobic ponds was not found to correlate with COD loading
or removal. |
