Effluent from a wastewater-treatment plant is discharged to a surface stream. The characteristics of the effluent and the stream are given in the table below. Determine the stream characteristics after mixing has occurred.
Parameter |
Effluent |
Stream |
Flow, |
8500 m3/day |
1.5 m3/sec |
BOD5, mg/L |
25.0 |
2.0 |
Ammonia, mg/L |
10.0 |
0.0 |
Nitrate, mg/L |
7.0 |
3.0 |
Chloride, mg/l |
15 |
5.0 |
a) The combined rate = effulent + stream = 8500 + 1.5 = 8501.5 m^3 / sec
b) Biological oxygen demand = flow rate of effulent X BOD of effulent +flow rate of stream x BOD of stream / total flow
BOD = 8500 X 25 + 1.5 X 2 / 8500 + 1.5 = 212500 + 3 / 8501.5 = 24.99 mg / L
C) Total ammonia = flow rate of effulent X ammonia +flow rate of stream x ammonia / total flow
Ammonia = 8500 X 10 + 0 / 8501.5 = 9.99 mg / L
D) Total nitrate = flow rate of effulent X nitrate of effulent +flow rate of stream x nitrate stream / total flow
Nitrate = 8500 X 7 + 1.5 X 3 / 8501.5 = 6.99 mg / L
E ) Total Chloride = flow rate of effulent X BOD of effulent +flow rate of stream x BOD of stream / total flow
Total chloride = 8500 X 15 + 5 X 1.5 / 8501.5 = 14.99 mg ./ L
Get Answers For Free
Most questions answered within 1 hours.