ANALYSIS OF DESIGN PARAMETERS OF FACULTATIVE WASTE STABILIZATION POND SYSTEM

Abstract

The waste stabilization ponds are the simplest of the waste water treatment techniques. Among them, facultative stabilization ponds are most popular. The present study is devoted to design methods of facultative waste stabilization ponds. Several numerical equations have been proposed to design facultative wastewater stabilization ponds. These design techniques include simple design criteria based on organic loading rate, empirical design equations and rational design equation. Attempts are made to obtain : a relationship between surface area, influent BOD5 and latitude, based on organic loading rate procedure, at constant flow rate; a relationship between optimal efficiency and influent BOD5 for two equal dimensioned ponds in series; a relationship between primary pond efficiency and influent BOD5 for two unequal dimensioned ponds in series; a relationship between optimal detention time and influent BOD5 for two ponds in series. It is observed that areas for primary ponds obtained from surface loading rate procedure are large especially at higher latitudes. For an influent BOD5 range of 100-1000 mg/l, two equal dimensioned ponds in series shall be desigfled . at efficiencies of 60% to 83% each, or at a detention periods of 8 to 30 days each, to get an effluent BOD5 of 30 mg/1. For a domestic waste of influent BOD5 300 mg/I, two equal dimensioned ponds in series shall be designed either at an efficiency of 69% each or at a detention period of 13 days each to get a effluent BOD5 of 30 mg/I.