turbidity measurement.pptx WATER TEST TREATMENT WATER

WATER TEST

1. Turbidity measurement By – praful hanmante

2. Contents B asics about turbidity Measurement units measurement techniques Calibration Application

3. Turbidity Turbidity is the amount of cloudiness in the water . It is indicator of water quality.

4. Inferences Particle size Bubbles Stray light Absorbing particles Contamination

5. Classification of devices 3 Factors affecting design of device Light source Detection angle Number of detector

6. Light source 3 most commonly used light sources Incandescent LED Laser based

7. Light sources Source Wavelength Application Incandescent light 400-600nm Shorter wavelength for short particles LED 830-890 nm Not effected by color in sample LASER 660nm Sensitive to smaller changes, Most effective for filtration

8. Detection angles 90 degree Most commonly used, 180 degree High turbidity application Backscatter detection angle High turbidity application Multiple detection angle Colour compensation Dual light source detector Correction for color absorption and optics fouling

9. Signal on 180 degrees detector What are we measuring ? Robert Lagrange Slide 12 Concentration Intensity

10. Signal on 90 degrees detector What are we measuring ? Robert Lagrange Slide 13 Concentration Intensity

11. Calibration Two point calibration -Zero point calibration- distilled water - Spanning the instrument Primary standard – formazin

12. comparison

13. Surface scatter

14. Hach turbidity meter

15. General guidelines Drinking water should have a turbidity of 5 NTU/JTU or less . • Where water is chlorinated, turbidity should be less than 5 NTU/JTU and preferably less than 1 NTU/JTU for chlorination to be effective .