Lab report Lab report ph and turbidity 1

Lab report ph and turbidity

1. 1
ENVIRONMENTAL ENGINEERING -II LAB
(CE-341)

FALL 2024 (09 SEP 2024 - 12 JAN 2025)
EXPERIMENT-1
“MEASUREMENT OF TEMPERATURE, PH &
TURBIDITY OF WATER SAMPLES”
Institute of Environmental Sciences and Engineering (IESE)
School of Civil and Environmental Engineering (SCEE)
NUST

2. THEORY
▪pH is measure of effective Hydrogen Ion Concentration
▪Defined as : pH = -log [H
+1
]
▪Low pH value corresponds to high concentrations of [H
+1
] and
vice versa
▪pH value measured on a scale of 0-14
▪pH value of 7 reflects neutral solution at 25
o
C
▪pH below 7 denote acidity, intensity of acidity increases as the
pH value decreases and vice versa
▪WHO and NEQS suggested a guideline value for pH For
drinking water its value should be in range of 6.5-8.5
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3. 3

4. PRINCIPLE
▪pH electrode used, is a combined glass electrode which consists
of sensing half cell and reference half cell. Sensing half cell is a
thin pH sensitive semipermeable membrane
▪Measures the voltage (electrical potential) produced by the
solution whose pH we're interested in, compares it with the
voltage of a known solution, and uses the difference in voltage
(the "potential difference") between them to deduce the
difference in pH.
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5. ENVIRONMENTAL SIGNIFICANCE
▪pH value or range is extremely important for any chemical
reaction as it highly effective at particular pH
▪Chemical coagulation, disinfection, water softening and
corrosion control are governed by pH adjustment.
▪Reduction of hexavalent chromium into trivalent chromium also
need favorable pH.
▪Prevents build-up of minerals (scale) on the inside of pipes,
fixtures, and hot water heaters. Lengthens the life of some
appliances. Reduces or prevents mineral spots on glassware.
Prevents or reduces soap films and detergent curds in sinks,
bathtubs, and washing machines
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6. APPARATUS/MATERIALS
▪pH meter
▪Beaker
▪Wash bottle
▪Buffer solution of different pH value
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7. PROCEDURE
▪Switch on the pH meter.
▪Remove the cap of electrode
▪Calibrate the pH meter by using different buffer solution of pH
4.0, 7.0 and 10
▪Place electrode in the sample
▪Be sure the entire sensing end is submerged and there are no air
bubbles under the electrode
▪Record pH value when the display is stable
▪Rinse the electrode with distilled water after each
measurement and calibration
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8. OBSERVATION/RESULTS
Sample pH
Tape water -
Sample 1 -
Sample 2 -
Sample 3 -
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9. CONCLUSION & COMMENTS
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10. TURBIDITY OF WATER SAMPLES
▪Turbidity is a measure of the level of particles such as
sediment, plankton, or organic by-products, in a body of water
▪Cloudiness or haziness of a fluid caused by large numbers of
individual/suspended particles.
▪Degree to which water loses its transparency
▪It's a key test in assessing water quality.
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11. ENVIRONMENTAL SIGNIFICANCE
▪Turbidity can indicate the presence of suspended solids in water, which
may include: Organic Matter, Bacteria/Microorganisms, Pollutants
▪High turbidity can affect aquatic ecosystems and human health
Applications
•Water Treatment Plants
•Monitoring drinking water quality.
•Environmental Monitoring
•Assessing river, lake, and ocean health.
•Wastewater Treatment
•Ensuring discharge water meets regulations.
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12. CAUSES OF TURBIDITY
▪Common causes of turbidity in water include:
▪Erosion and runoff
▪Wastewater discharge
▪Algae blooms
▪Urbanization and construction
▪Nephelometric Turbidity Unit (NTU): The most common unit for
measuring turbidity.
▪Standards: WHO recommends a turbidity level of less than 5 NTU for
drinking water.
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13. METHODS TO MEASURE TURBIDITY
Visual Inspection:
▪Traditional method, less accurate.
Turbidity Meters:
▪Modern, accurate devices using light scattering techniques.
▪Types: Nephelometric and Secchi disk methods.
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14. PRINCIPLE - TURBIDITY METERS
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▪Nephelometric Method: Through
Nephelometer (Turbidity meter)
▪Light is passed through the water
sample.
▪Scattered light is measured.
▪More scattered light = higher turbidity.

15. ▪Secchi Disk Method:
▪For open bodies of water.
▪A disk is lowered into the water until it is no longer visible.
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16. APPARATUS/MATERIALS
▪Turbidimeter
▪Distilled water
▪Beaker
▪Wash bottle
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17. PROCEDURE
▪Sample Collection: Collect the water sample in clean, non-reactive
containers.
▪Calibration of the Turbidity Meter
▪Sample Preparation: Ensure the sample is free from bubbles and large
particles.
▪Measurement: Place the sample in the meter and record turbidity value
(usually in NTU).
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18. OBSERVATION/RESULTS
INTERPRETING RESULTS
•Low Turbidity (< 1 NTU): Clean water, safe for drinking.
•Moderate Turbidity (1 - 5 NTU): Suspended particles, may
need treatment.
•High Turbidity (> 5 NTU): Likely pollution, needs investigation
and treatment.
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19. CONCLUSION & COMMENTS
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20. SAFETY MEASURES
▪Wear Lab Coats, Closed toe shoe and masks while performing
experiment.
▪Tie your hair
▪Don’t mix any type of solutions especially adding water to the
acids
▪Keep your bags away from the working area
▪Report any breakage/spill etc to Lab Engineer/Demo
▪In case of any emergency, contact with Lab Engineer/Demo and
Lab Technician
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21. Thank you
You can contact me at:
[email protected]
051 9085 4289
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