This document summarizes key parameters for characterizing wastewater: pH, total suspended solids (TSS), total dissolved solids (TDS), dissolved oxygen (DO), chemical oxygen demand (COD), and biological oxygen demand (BOD). It provides the typical ranges for these parameters in wastewater and describes the methods for measuring each one, such as using electrodes to measure pH, filtering samples to determine TSS, and titration methods for COD and BOD. Maintaining these parameters within the given ranges is important for ensuring good water quality.

1. Md. Shah Paran
BTX-110300161

2. Presentation on Wastewater
Characterization
Presented by
Supervisor
Md. Tanjim Hossain
Lecturer & Co-ordinator
Dept. of Textile Engineering
ID Name Remark
110300161 Md Shah Paran
120100079 Abdul Waras

3. The wastewater characterized by
1) pH Scale
2) Total Suspended Solid (TSS)
3) Total Dissolved Solid (TDS)
4) Dissolved Oxygen (DO)
5) Chemical Oxygen Demand (COD)
6) Biological Oxygen Demand (BOD)

4. Parameter Range
pH 6-9
TSS Less then 150 ppm
TDS Less than 2100 ppm
DO 4.5-8
COD Less than 200 ppm
BOD Less than 50 ppm

5.  pH is the abbreviation of pondus hydrogen
 pH = -log [H+]
 [H+] is in molar concentration

7. Electrochemical method
 Depends on hydrogen activity
in the solution
 It consists of two electrodes
1. Measuring electrode
2. Reference electrode

8.  Dependent on
hydrogen
activity
 Glass membrane is
sensitive to H+ ions

9. • insensitive to the
H+ ions in the solution
• most widely used is the
silver/silver chloride
electrode
• another commonly used
reference electrode is the
calomel electrode

10.  Optical Methods
-Indicator papers
 ISFET electrode

11.  The solids retained on a filter paper of pore size 2.0
µm or smaller, during the filtration of the sample
water
 Total Suspended Solids are the amount of filterable
solids in a water sample. Samples are filtered
through a glass fiber filter. The filters are dried and
weighed to determine total suspended solids in
mg/L.

12.  Prepare a 0.45 micron filter using wash-dry-cool cycle
 Seat filter with DI water prior to filtration
 Pippet a measured volume into filtration apparatus
from stirred sample
 Wash filter with 3 x 10 mL washings DI water
 Apply suction for 3 minutes after washing
 Transfer to aluminum dish for support
 Dry in the oven at 103-105 °C overnight (should be 1 h)
 Place in a desiccator to cool to room temperature,
reweigh to the nearest 0.1 mg
 Calculate TSS in mg/L

13. Total suspended solids (TSS) :
The total suspended solids (TSS) is given by thefollowing
formula:
mg/L Total suspended solids = ( A-B) × 1000 / ml sample
Where,
A = weight of filter disk with dried residue
B = weight of filter disk only

14.  The solids that pass through the filter paper during
the filtration of sample water
 Total Dissolved Solids are those solids (inorganic +
organic) that pass through a filter of 2.0 μm or
smaller. They are said to be non-filterable. After
filtration the filtrate (liquid) is dried and the
remaining residue is weighed and calculated as
mg/L of Total Dissolved Solids

15. 1. Dry a clean dry beaker at 103-105 °C for at least 1 hour
2. Desiccate until cool and weigh to nearest 0.1 mg
3. Filter 50.0 mL through a 0.45 μm filter paper into clean
dry beaker using technique described above
4. Heat the sample to just below boiling and reduce the
volume to 10 mL
5. Allow the beaker to cool and dry in the oven at 103-105
°C overnight
6. Remove the beaker and place in a desicator to cool to
room temperature, reweigh to the nearest 0.1 mg
7. Calculate TDS in mg/L

16. Total Dissolved solids (TDS):
The total dissolved solids are given by the formula:
mg/L Total dissolved solids = ( A-B) × 1000 / ml sample
Where;
A = weight of dried residue + dish weight (mg)
B = weight of dish (mg)

17. Abdul Waras
BTX-120100079

19.  Dissolved Oxygen is the amount of gaseous oxygen
(O2) dissolved in the water. Oxygen enters the water
by direct absorption from the atmosphere, by rapid
movement, or as a waste product of plant
photosynthesis. Water temperature and the volume of
moving water can affect dissolved oxygen levels.
Oxygen dissolves easier in cooler water than warmer
water.

20.  Adequate dissolved oxygen is important for
good water quality and necessary to all forms
of life. Dissolved oxygen levels that drop
below 5.0 mg/L cause stress to aquatic life.
Lower concentrations cause greater stress.
Oxygen levels that go below 1-2 mg/L for a
few hours may result in large fish kills.

21. Materials:
 300.0 ml BOD bottles or SOLA (glass) bottles with
cap
 250.0 ml graduated cylinder
 500.0 ml Erlenmeyer flasks
 1.0 ml Pipettes
 Rubber aspirator
 Titration set-up

22.  Collect samples in a 300 mL SOLA bottle
 Add 2ml of manganous sulfate solution
 Add 2 ml of alkaline-iodide-sodium azide
solution
 Shake the bottle by inverting several times
 Allow solution to settle
 Add 2ml of conc. sulfuric acid
 Shake well until precipitate is dissolved

23.  Pour 200ml of sample from the SOLA bottle into an
Erlenmeyer flask
If the solution is
reddish-brown in
color, titrate with
0.0250 N sodium
thiosulfate
If the solution has no
reddish-brown color, or is
only slightly colored,
add a small quantity
(approx. 1 mL) of starch
indicator.

24. BOD is the amount of dissolved oxygen needed
by aerobic biological organism in a body of
water to breakdown organic material present in
a given water sample at certain temperature
over a specific time period (5 days).

25. ANOXIA: When dissolve oxygen content below 0.5 mg/L. All
aerobic species will die.

26. A. Dilution
Dilution Factor: The dilution factor, DF, is the ratio of the
final volume to the volume of sample therein. (e.g., for
the bottle method, the volume of the BOD bottle,
usually 300 mL; for the graduated bottle, usually 300
mL; for the graduated cylinder method, the volume of
the cylinder, usually 1000 mL).
DF for the bottle method = {Volume of
Diluted Mixture÷Volume of Sample in
Mixture

27. B. DO fixation
1. Slowly siphon three portions of aerated dilution water
into three separate BOD bottles. Avoid adding
atmospheric O2to dilution water.
2. To two of the three BOD bottles, add 1 2.To two of the
three BOD bottles, add 1 ml MnS04solution, followed
by 1 ml alkali-iodide-azide reagent. Submerge pipette
tips in sample when adding reagents. Rinse tips well
between uses.
3. Stopper carefully to exclude air bubbles; mix by
inverting bottle several times.
4.When precipitate has settled to about half the bottle
volume, carefully half the bottle volume, carefully
remove the stopper and add 1.0 ml conc. sulfuric acid.
Re-stopper and mix by gentle inversion until the iodine
is uniformly distributed throughout the bottle.

28. C. DO Measurement
5. Transfer 203 ml of sample into conical flask and
titrate with 0.0250N sodium thiosulfate to a pale
straw color.
6. Add 1-2 ml of starch solution and continue to
titrate to first disappearance continue to titrate to
first disappearance of the blue color. (200 ml of
original dilution water is equal to 203 ml of
dilution water plus reagents).
7. Determine the initial concentration of dissolved
oxygen in one bottle of the mixture of sample and
dilution water (DO), and in one of the water
(DOinitial), and in one of the bottles containing
only dilution water.

29. 8. Place the other bottles in the incubator
9. Incubate the blank dilution water and the diluted
samples for 5 days in the dark at 20 °C.
10. After 5 days, remove the bottles, fix the DO and
measure the DO (DOfinal) DO and measure the DO
(DOfinal)
11. Calculate BOD5
BOD5(mg/L) = {DOinitial(mg/L) of first bottle -
DOfinal(mg/L) of second bottle} x dilution factor

30. COD is the total amount of oxygen required to
chemically oxidize the bio degradable and non-
biodegradable organic matter.
It is expressed in milligrams per liter (mg/L) also
referred to as ppm (parts per million), which
indicates the mass of oxygen consumed per liter
of solution.

31.  Water sample is refluxed in strong acidic solution
with a known excess amount of potassium
dichromate.
 After digestion, the remaining unreduced K2Cr2O7
is titrated with Ferrous Ammonium Sulfate (FAS)to
determine K2Cr2O7 consumed.
 This gives us the oxidizable organic matter in
terms of oxygen equivalent.

32. 1. Wash 300 ml round bottom refluxing flask.
2. In refluxing flask put one spatula of HgSO4 + 10 ml
sample + 5ml K2Cr2O7 + 15 ml concentrated H2SO4.
3. Add small amount of silver sulphate.
4. Shake well and reflux for 2 hr.
5. Cool and add little amount of distilled water to the
flask through the condenser
6. Titrate the solution in the flask against FAS using
Ferrion indicator
7. End point green color to reddish brown

33. CALCULATIONS
 The COD in mg/l is determined by the formula,
COD mg/l = (A-B)xNx8000
ml sample taken
A = ml of FAS required for blank.
B = ml of FAS requires for sample.

34. Thank You
For Your
Kind Attention