Water purification is the most essential aspect to make sure that you have safe and clear water to drink. One of the most effective methods for purifying water, especially in large-scale municipal or industrial applications is the use of aluminium sulphate. 

It is a compound that is usually referred to as alum and has a crucial role in the water treatment process. Here you will learn how you can use this to purify the water more effectively. 

What is Aluminium Sulphate? 

Aluminium sulphate (Al2(SO4)3) is a chemical compound that appears as a white, crystalline solid. It is widely used in plants as a coagulant and aluminium sulphate solid from buyers has a positive response. 

The primary function of this compound is to help remove impurities and suspended particles from water. It causes them to clump together which makes it easier to filter them out. 

The Water Purification Process 

It is good for you to know the water purification process before you get into using the aluminium sulphate. The typical step includes; 

Coagulation and Flocculation 

It is where the aluminium sulphate comes into play. Coagulates are added to water to destabilize the suspended particles. 

Sedimentation 

The clumped particles settle at the bottom of the treatment tank. 

Filtration 

The clear water on top is filtered to remove any remaining particles.    

Disinfection 

The water is treated with disinfectants to kill any remaining pathogens. 

Steps to Purify Water Using Aluminium Sulphate

Pre-Treatment Assessment 

You should conduct a water quality assessment. It includes measuring pH, turbidity, and the concentration of suspended solids. It will help in determining the appropriate dosage of aluminium sulphate.  

Calculate Dosage 

The dosage of aluminium sulphate needed depends on the quality of the water. A jar test is typically conducted to know the optimal dosage. It involves adding different concentrations of aluminium sulphate to samples of water and observing which dose results in the best coagulation.  

Prepare the Aluminium Sulphur Solution  

Aluminium sulphate is usually added to the water in dissolved form. You can prepare the solution by measuring the required amount and dissolving it in water. Based on the jar test results, you should measure the required amount of the compound. And then dissolve the measured amount of aluminium sulphate in a container of water. Don’t forget to stir well to make sure that it is completely dissolved.  

Add the Aluminium Sulphate to the Water 

Add the aluminium sulphate solution to the water while stirring vigorously to ensure the even distribution. The rapid mixing helps in the formation of micro flocs. After the initial rapid mixing, slow down the stirring. It will allow the micro flocs to aggregate into larger and more visible flocs. 

Allow Sedimentation 

Once the flocs have formed, you should allow the water to sit undisturbed in a sedimentation tank. The flocs will be heavier than the water and will gradually settle at the bottom of the tank of water. The process can take anywhere from 1 to 4 hours. It depends on the size of the floc and the quality of the water. 

Filtration 

After the sedimentation, the clear water from the top is passed through a filtration system to remove any type of remaining particles. Some common filtration methods include sand filters, membrane filters, and activated carbon filters. The step is to make sure that the water is free of flocs and other impurities. 

Disinfection 

Although aluminium sulphate effectively removes most of the impurities, it does not kill the pathogens. That is why, the final step is to disinfect the water. The most known disinfectants include chlorine, chloramine, and ultraviolet (UV) light. It is to keep the water safe for consumption. 

Safety Precautions 

When you are handling the aluminium sulphate, make sure to follow the guidelines to avoid any health hazards. 

Wear gloves, safety goggles, and a mask to prevent contact with the skin, eyes, and respiratory system. 

Store aluminium sulphate in a dry, cool place that is away from incompatible substances like strong acids and bases. 

Handle with care to avoid spills and exposure. In case of contact with skin or eyes, rinse immediately with plenty of water and seek medical attention if necessary. 

Conclusion

So, this is how you can use the aluminium sulphate to keep the water tanks and other containers pure. Make sure you follow all steps to ensure the water is safe for drinking and other uses such as cooking. Stay healthy by keeping your water tanks clean and pure.