Comparisons between fecl3 and alum performance in Clarifier

Ferric chloride and alum are two common coagulants used in water treatment for flocculation, a process that helps in the removal of suspended particles from water. Let's compare the two in terms of their characteristics and effectiveness in water treatment: Ferric Chloride (FeCl3): 1. Chemical Properties: • Ferric chloride is a chemical compound with the formula FeCl3. • It is a dark brown, highly corrosive, and acidic solution. 2. Coagulation Mechanism: • Ferric chloride works primarily through charge neutralization and adsorption mechanisms. • It reacts with water to form various hydrolysis species that neutralize the negative charges on particles, promoting aggregation. 3. Effectiveness: • Ferric chloride is effective in treating a wide range of contaminants, including suspended solids, phosphates, and heavy metals. • It is particularly useful in wastewater treatment for industrial applications. 4. pH Sensitivity: • Ferric chloride is less sensitive to variations in pH compared to some other coagulants. 5. Cost: • The cost of ferric chloride can vary, but it is generally competitive with other coagulants. Alum (Aluminum Sulfate, Al2(SO4)3): 1. Chemical Properties: • Alum is a chemical compound containing aluminum, sulfur, and oxygen. • Aluminum sulfate (Al2(SO4)3) is commonly used as alum in water treatment. 2. Coagulation Mechanism: • Alum primarily functions through charge neutralization and precipitation. • It forms aluminum hydroxide floc, which entraps impurities and settles out of the water. 3. Effectiveness: • Alum is effective in treating suspended particles, turbidity, and some heavy metals. • It is widely used in municipal water treatment. 4. pH Sensitivity: • Alum is more sensitive to pH variations. Optimal performance is often achieved at a relatively narrow pH range. 5. Cost: • Alum is generally cost-effective, and it has been traditionally used in water treatment processes. Comparison: 1. Application: • Ferric chloride is often preferred in industrial applications due to its effectiveness against a broader range of contaminants. • Alum is commonly used in municipal water treatment for its reliable performance. 2. Handling and Storage: • Ferric chloride is a liquid, while alum is often supplied in a solid form. Handling considerations may vary. 3. pH Control: • Ferric chloride offers more flexibility in pH conditions, making it suitable for a wider range of water sources. • Alum may require additional pH adjustment for optimal performance. In summary, the choice between ferric chloride and alum depends on the specific water treatment requirements, the types of contaminants present, and the characteristics of the water source. Both coagulants play crucial roles in water treatment and are selected based on their efficacy and cost-effectiveness in a given context. Solution preparation: A) Ferric chloride solution : Take 1.0 gm powder of ferric chloride dissolved in 100 ml of D.M. water(1.0 w/v solution ) PH -2.02 And conductivity -16100ms B) Alum solution :Take 1.0 gm powder of alum dissolved in 100 ml of DM water (1.0w/v solution) PH-2.82 AND conductivity -4060ms Raw water (Reservoir water ): 1000 ml sample taken from reservoir having 5 NTU Turbidity and other parameters are following PH -8.98 Electro-conductivity -622.0 Total dissolved solids -404.3 Total Hardness -134.0 p- Alkalinity -16.0 M-Alkalinity -86.0 Chloride -103.6 Silica -8.34 Turbidity-5.0 NTU Procedure: In Jar test taken samples of 1000 ml of each.and added above prepared solution 10 ml fecl3 and alum two both beaker and kept it for stirring for an hour from 3.30 pm to 4.30 pm. Afterwards kept it for settling for both the samples from 4.30 pm to 5.30 pm. After wards separated it by slowly and get sample and analysis of both samples as below

Observation –  Rate of settling of ferric chloride is higher and fastest than Alum .But having sludge formation more than alum .  Rate of consumption of ferric chloride is lesser than alum consumption. And costing is also lesser than alum costing.  Turbidity on outlet of ferric chloride is also lesser than Alum, in alum some haziness found in outlet of clarifier.  In ferric chloride pale yellowish coloration get takes place if dosing is not optimum. parameters Raw water untreated (Resrvoir) Ferric chloride treated water Alum treated water pH 8.98 6.80 7.22 Electro-conductivity 622.0 687.0 644.0 Total dissolved solids 404.3 446.6 418.6 Total hardness 133.0 133.6 133.0 Ca-Hardness 78.0 87.6 83.0 Mg-hardness 54.0 46.0 50.0 p-alkalinity 16.0 Nil Nil m-alkalinity 86.0 38 58 silica 8.34 6.49 6.18 turbidity 5.0 nil 1.0 chloride 103.6 167.5 106.5 Sludge ----------- 0.0857 gm/LTR 0.0492 gm/LTR CONSUMPTION/MONTH 750 KG 2025KG COSTING/MONTH 27 X750 18X2025 20250 RS 36450 RS