The dry weather average flow rate for a river is 8.7 m3/s. During dry weather flow, the average COD concentration in the river is 32 mg/L. An industrial source continuously discharges 18,000 m3/d of wastewater contains an average 342 mg/L COD concentration into the river. What is the COD mass loading in the river upstream of the industrial source discharge

6156 kg /day

Explanation:

Determine the COD mass loading in the river upstream of the industrial source discharge

Given data:

Flow rate of river = 8.7 m^3/s

Average COD concentration in river = 32 mg/L

Industrial source continuous discharge ( Qw )= 18,000 m^3/d

Yw = 342 mg/l

since :

1 m^3 = 1000 liters

Qw = 18 * 10^6  liters = ( 18 million per day )

Hence the COD mass loading

= Yw * Qw

= 342 * 18 liters

= 6156 kg /day