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Environmental monitoring

Environmental monitoring

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Environmental monitoring

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  1. MEASUREMENT OF POLLUTANTS IN WATER • There are 3 kinds of water: • drinking water • waste water • surface water • Drinking water or potable water is water of sufficiently high quality that can be consumed or used without risk of immediate or long term harm. It is provided by water supply networks or may be found in deep wells or springs. • Waste water or sewage comprises liquid waste discharged by domestic residences, commercial properties, industry, and/or agriculture and can encompass a wide range of potential contaminants and concentrations. In the most common usage, it refers to the municipal wastewater that contains a broad spectrum of contaminants resulting from the mixing of wastewaters from different sources. • Surface water is water collecting on the ground or in a stream, river, lake, wetland, or ocean; it is related to water collecting as groundwater or atmospheric water. Environmental monitoring

  2. Environmental monitoring Environment Monitor Water Quality (video clip)

  3. MEASUREMENT OF POLLUTANTS IN WATER Regulations Environmental Protection Law 137/1995 updated by Ordonance 195/2005 Environmental monitoring Waste water • Law: HG 352/2005, completion of HG 188/2002 refers to 2 types of waste water: • industrial and urban waste waters overflowed into natural receivers (lakes, rivers) (NTPA 001) • waste waters overflowed into sewerage networks (NTPA 002)

  4. MEASUREMENT OF POLLUTANTS IN WATER Waste water quality standard NTPA 001 (several chemical indicators)

  5. MEASUREMENT OF POLLUTANTS IN WATER Waste water quality standard NTPA 002 (several chemical indicators)

  6. MEASUREMENT OF POLLUTANTS IN WATER Regulations Drinking water Law 311/2004, completion of Law 458/2002 Environmental monitoring Microbiological parameters

  7. MEASUREMENT OF POLLUTANTS IN WATER Drinking water Law 311/2004, completion of Law 458/2002 Chemical parameters Environmental monitoring

  8. MEASUREMENT OF POLLUTANTS IN WATER Drinking water – USA National Primary D.W. regulations Environmental monitoring

  9. MEASUREMENT OF POLLUTANTS IN WATER Drinking water – USA National Primary D.W. regulations Environmental monitoring

  10. MEASUREMENT OF POLLUTANTS IN WATER Surface water Law Order 1146/10.12.2002 Chemical parameters Environmental monitoring

  11. MEASUREMENT OF POLLUTANTS IN WATER • How to measure all of these parameters? • There are various methods, techniques and equipments devoted to measure water quality parameters. • They are divided in: • in-situ methods • laboratory methods Environmental monitoring

  12. MEASUREMENT OF POLLUTANTS IN WATER Environmental monitoring Water sampling (video clip)

  13. Measurement of water pollutants using ion selective electrodes (ISE) Environmental monitoring

  14. Measurement of water pollutants using ion selective electrodes (ISE) Environmental monitoring Ion selective electrodes (video clip)

  15. Measurement of water pollutants using ion selective electrodes (ISE) Ions to be measured using ISE Cations Ammonium (NH4+) Barium (Ba2+) Calcium (Ca2+) Copper (Cu2+) Lead (Pb2+) Mercury (Hg2+) Potassium (K+) Sodium (Na+) Silver (Ag+) Anions Bromide (Br-) Chloride (Cl-) Cyanide (CN-), Fluoride (F-) Iodide (I-) Nitrate (NO3-) Nitrite (NO2) Perchlorate (ClO4-) Sulphide (S-) Thiocyanate (SCN). Environmental monitoring

  16. Measurement of water pollutants using ion selective electrodes (ISE) Advantages of measuring using ISE Environmental monitoring • very fast and easy measurements • the possibility of implementation of continuous monitoring • relatively inexpensive • wide range of concentration for a large variety of ions • by fulfilling the imposed conditions of maintenance and calibration, one can achieve accuracy and precision levels of 2 – 3 %, sometimes comparable with analytical techniques. • unaffected by sample colour and turbidity.

  17. Measurement of water pollutants using ion selective electrodes (ISE) Environmental monitoring

  18. Measurement of water pollutants using ion selective electrodes (ISE) Measurement principle of ISE (example pH measurement) Environmental monitoring Reference electrode Measurement electrode

  19. Wire connection Wire connection Wire connection Reference electrode Measurement electrode Glass body Glass or plastic body Glass body Filled with potassium chloride buffer solution Bulb filled with potassium chloride buffer solution Bulb filled with potassium chloride buffer solution Porous junction Very thin glass bulb chemically doped with lithium ions Very thin glass bulb chemically doped with lithium ions Voltage produced across thickness of glass membrane Voltage produced across thickness of glass membrane Measurement of water pollutants using ion selective electrodes (ISE) Measurement and reference electrodes Environmental monitoring Measurement electrode

  20. Measurement of water pollutants using ion selective electrodes (ISE) Nernst equation Environmental monitoring a = activity of ions (for pH, a is the activity of hydrogen ions) C = ion concentration γ = activity coefficient E = measured potential E0 = standard electrode potential (E for a = 1) R = gas constant T = absolute temperature [K] F = Faraday constant n = ion charge (n = 1 for pH)

  21. Measurement of water pollutants using ion selective electrodes (ISE) 50 oC Environmental monitoring 25 oC

  22. Measurement of water pollutants using ion selective electrodes (ISE) Environmental monitoring

  23. reference filling hole shielded cable filling hole reference electode (Ag/AgCl) reference junction KCl junction glass frit measurement electode (Ag/AgCl) membrane Measurement of water pollutants using ion selective electrodes (ISE) Combined (double junction) electrode Environmental monitoring

  24. Gate Sensitive layer Insulator Drain Source Substrate p-type Si Measurement of water pollutants using ion selective field effect transistors (ISFET) Principle of operation of an ISFET Environmental monitoring D G VDS ID VGS S

  25. Measurement of water pollutants using ion selective field effect transistors (ISFET) Some ISFET Characteristics Environmental monitoring

  26. Monochrome light Light detector ν0 ν1 Sample MEASUREMENT OF POLLUTANTS IN WATER Optical methods E = hc/λ = hν • They are based on: • reflection • colorimetry • absorbtion of light • fluorescence Planck equation h = Planck’s constant (6.626 ·10-34 J·s) C = velocity of light in vacuum λ = wave length ν = light frequency Environmental monitoring Fluorescence This method utilizes the fluorescence, either natural or induced, of a compound. Fluorescent chemicals absorb radiation of a specific wavelength and emit at another.

  27. Light detectors White light or infrared light White light or infrared light MEASUREMENT OF POLLUTANTS IN WATER Optical methods Nephelometry Environmental monitoring

  28. Monochrome light Light detector I0 I Sample MEASUREMENT OF POLLUTANTS IN WATER Optical methods Colorimetry A = log(I/Io) = knC Beer’s law Environmental monitoring Visual tests Photometer

  29. MEASUREMENT OF POLLUTANTS IN WATER Colorimetry Environmental monitoring Water Quality Colorimeter (video clip)

  30. Measurement of water parameters using UV-VIS spectrophotometer method The measurements may be performed in laboratory or in the field Environmental monitoring

  31. Measurement of water parameters using UV-VIS spectrophotometer method Spectrophotometer DR 2800 Environmental monitoring

  32. Measurement of water parameters using UV-VIS spectrophotometer method Spectrophotometer DR 5000 Environmental monitoring

  33. Measurement of water parameters using UV-VIS spectrophotometer method Environmental monitoring

  34. Measurement of water parameters using UV-VIS spectrophotometer method Cuvette tests method Environmental monitoring

  35. Measurement of water parameters using UV-VIS spectrophotometer method Environmental monitoring

  36. Measurement of water parameters using UV-VIS spectrophotometer method Environmental monitoring

  37. Measurement of water parameters using UV-VIS spectrophotometer method Environmental monitoring

  38. Measurement of water parameters using UV-VIS spectrophotometer method Parameters to be measured Environmental monitoring

  39. Measurement of water parameters using UV-VIS spectrophotometer method Hach robot for spectrophotometric measurements (video clip) Environmental monitoring

  40. MEASUREMENT OF POLLUTANTS IN WATER Measurement of metals using Atomic Absorption Spectrophotometry (AAS) Environmental monitoring

  41. MEASUREMENT OF POLLUTANTS IN WATER Measurement of metals using Atomic Absorption Spectrophotometry Beer – Lambert’s law Environmental monitoring T = transmission (transmissivity) α = absorbtion coefficient l = pass length (distance the light travels through the material ε = molar absorptivity of the absorber c = concentration of the absorber in the material

  42. MEASUREMENT OF POLLUTANTS IN WATER Measurement of metals using Atomic Absorption Spectrophotometry Difference between atomic and molecular spectroscopy Environmental monitoring

  43. MEASUREMENT OF POLLUTANTS IN WATER Measurement of metals using Atomic Absorption Spectrophotometry Analytik Jena Zeenit A700 AAS spectrophotometer Environmental monitoring

  44. MEASUREMENT OF POLLUTANTS IN WATER Measurement of metals using Atomic Absorption Spectrophotometry AAS Block Diagram Environmental monitoring

  45. MEASUREMENT OF POLLUTANTS IN WATER Measurement of metals using Atomic Absorption Spectrophotometry Flames used in AAS Environmental monitoring

  46. MEASUREMENT OF POLLUTANTS IN WATER Measurement of metals using Atomic Absorption Spectrophotometry Light source Environmental monitoring Hollow cathode lamp Xenon lamp

  47. MEASUREMENT OF POLLUTANTS IN WATER Measurement of metals using Atomic Absorption Spectrophotometry Detection limits for some elements (μg/l) Environmental monitoring

  48. MEASUREMENT OF POLLUTANTS IN WATER Dissolved Oxygen (DO) Measurement • Dissolved oxygen analysis can be used to determine: • the health or cleanliness of a lake or stream, • the amount and type of biomass a freshwater system can support, • the amount of decomposition occurring in the lake or stream. Environmental monitoring • There are three methods: • Azide-Winkler method • Metering with DO probe • Field kits

  49. MEASUREMENT OF POLLUTANTS IN WATER Dissolved Oxygen (DO) Measurement (Winkler method) Environmental monitoring