PARAMETERS FOR ANALYSIS
1. ELECTRICAL CONDUCTIVITY
2. DISSOLVED OXYGEN TEST
3. BIOLOGICAL OXYGEN DEMAND TEST
4. CHEMICAL OXYGEN DEMAND TEST
6. TOTAL DISSOLVED SOLIDS
5ml of waste water sample was introduced into the 300 ml of BOD bottle. The lid of bottle was tightened so that no air bubble could reside in it. It was then sealed and after that addition of deionized water was carried out in the bottle.
At the beginning stage of calculating BOD by using dissolved oxygen meter, value of the dissolved oxygen was found to be 8mg/L.
After this, bottle was to be left in the incubator for five days.
After five days, final value of dissolved oxygen was again measured by using the DO meter. It was found to be about 4mg/L.
Value of BOD was then calculated by putting the final and initial value in the given formula.
BOD= 8-4 mg/L= 4mg/L.
DISSOLVED OXYGEN TEST
• This test is used to determine the value of dissolved oxygen present in the given sample of waste water.
• Measurement of dissolved oxygen was calculated by fitting electronic meter with particular probe of DO.
• Value of DO of waste water is affected by the following factors:
Value of DO decreases by increase in temperature of water.
Dissolved oxygen value decline by increase in salinity.
Value of dissolve oxygen increases when the pressure increases.
°C °F CONCENTRATION OF DO AT SATURATION (mg/L)
0 32 14.6
5 41 13.1
10 50 11.3
15 59 10.1
20 68 9.1
25 77 8.2