Inlet Parameters [mg/ltr] | Outlet[mg/ltr] | Tertiary | |
---|---|---|---|
BOD | 200-400 | 10-20 | 4-5 |
COD | 300-500 | 20-30 | 10-5 |
pH | 5-8 | 7 | |
Nitrogen | 10-40 | 1-2 | |
Phosphorus | 10-40 | 1-2 | |
TSS | 150-350 | 10-15 |
Note: The above mentioned parameters of treated water very well meet the CPCB and NGT norms, regarding the same.
ACF : Granular activated carbon (GAC) is commonly used for removing organic constituents and residual disinfectants in water supplies. This improves taste and minimizes health hazards; Activated carbon is a
favored water treatment technique because of its multifunctional nature and the fact that it adds nothing detrimental to the treated water.
However, different raw materials produce different types of activated carbon varying in hardness, density, pore and particle sizes, surface areas, extractables, ash and pH. These differences in properties make certain carbons preferable over others in different applications.
SPF : Raw water is passed through thepressure sand filter, the filter media (Fine quartzsand) is supported on gravel & pebbles bed of progressively larger sizes. During the filtration cycle the filter bed retains the dirt and suspended particles from the water and accumulates within the filter bed.
Ozone has a greater disinfection effectiveness against bacteria and viruses compared to chlorination. In addition, the oxidizing properties can also reduce the concentration of iron, manganese, sulfur and reduce or eliminate taste and odor problems. Ozone oxides the iron, manganese, and sulfur in the water to form insoluble metal oxides or elemental sulfur. These insoluble particles are then removed by post-filtration. Organic particles and chemicals will be eliminated through either coagulation or chemical oxidation. Ozone is unstable, and it will degrade over a time frame ranging from a few seconds to 30 minutes. The rate of degradation is a function of
water chemistry, pH and water temperature.
PARAMETER | Design for ETP | ||
---|---|---|---|
Guideline Values | Average | Maximum | |
pH, pH units | 6.00-9.00 | 4.8 | 11.1 |
Conductivity, μS/cm | 40 | 1500 | 2100 |
Appearance | clear | Unclear | Unclear |
Colour, Hz | 200 | 200 | 400 |
Turbidity, NTU | 5.0 | 900 | 2700 |
Flouride | 1.5max | <0.005 | <0.005 |
Total Dissolved Solids (TDS) | 500mg/l | 1200 | 1500 |
Biochemical Oxygen Demand (BOD) | 30.0mg/l | 1200 | 2900 |
Chemical Oxygen Demand (COD) | 60.0mg/l | 4500 | 6600 |
Oil/Grease | 5.0mg/l | 12 | 780 |
Total Phosphate | 2.0mg/l | 1 | 3 |
Ammonia- Nitrogen (NH3-N) | 1.00 | 55 | 70 |
Nitrate-Nitrogen (NO3 -N) | 10mg/l | 0.3 | 26.4 |
Alkalinity | 150mg/l | 175 | 350 |
Sulphide | 1.50 | <0.005 | 0.35 |
Chloride | 250 | 250 | 560 |
Total Coliform (cfu/100ml) | Nil/Negative | 124 x 104 | 155 x 104 |
E-coli cfu/100ml | Negative/Nil | 69 x 103 | 95 x 103 |
Dissolved Oxygen | > 2mg/l | 2.55 | 2.86 |