THE FORECASTING OF SULFIDE BUILD-UP RATES IN SEWERS

SUMMARY A practical equation for forecasting sulfide buildup in partly filled sewers must be limited to the use of input information that is reasonably obtainable by measurement or estimation. For this reason, it appears that forecasting will generally be limited by the assumption that certain unquantified variables, especially the dissolved oxygen content of the sewage stream, are in ranges favorable for sulfide buildup. An equation constructed with this limitation gives results that are inherently conservative, but useful for engineering purposes. Sulfide buildup rates will rarely exceed by any significant amount the rates calculated by the following equation: d [ S ] d t = 0.32 x 10 − 3 [ B O D ] ( 1.07 ) ( T − 20 ) − 0.64 ( s u ) 3 / 8 [ s ] d m − 1