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Coagulation and flocculation are important processes in water treatment with coagulation aimed to destabilize and aggregate particles through chemical interactions between the coagulant and colloids, and flocculation to sediment the destabilized particles by causing their aggregation into floc.
Why is flocculation important?
Used water can contain significant amounts of suspended particulate matter, which often takes long to sediment. Flocculation expedites sedimentation and ensures efficient solid/liquid separation.
What makes a good flocculant?
Polymers are useful as flocculants because they are robust molecules and sometimes carry charges. Because they are so large, small particles can get trapped in the curves of the polymer causing them to accumulate a mass heavy enough to prevent their retention in solution.
How long does pool flocculant take to work?
It works slowly. It may be two or three days before your pool is completely clear, depending on the severity of the cloudiness. You’ll need to clean the filter.
Does flocculant affect pH?
Because flocculants can affect the pH level, you’ll want to start out with it at about 7.0 so you can make sure your sanitizer keeps working at maximum efficiency.
How can flocculation be prevented?
When particles of a suspension come close together they can form aggregates called flocculates which will settle more rapidly. To prevent that we often coat the particle with a charged surfactant. The charge (Zeta potential) acts to keep the particles separate and prevent flocculation.
What is the difference between flocculant and coagulant?
Depending on the charge and chemical composition of your wastewater, flocculants can either be used on their own or in combination with coagulants. Flocculants differ from coagulants in that they are often polymers, whereas coagulants are typically salts.
What two chemicals are commonly used as water coagulants?
Aluminum sulfate (alum) is the most common coagulant used for water purification. Other chemicals, such as ferric sulfate or sodium aluminate, may also be used.
What is the principle of flocculation?
Coagulation – flocculation is physico-chemical process that facilitates the agglomeration of fine particles (colloids) contained in water to form a floc that can be easily filtered from water. Effluent (waste water) must be treated before it is discharged or before the water is re-used.
What chemicals are flocculants?
A flocculants are usually organic chemicals added to wastewater to enhance flocculation, such chemicals are alum, aluminium chlorohydrate, aluminium sulphate etc.
Is FeCl3 a coagulant?
Ferric chloride (FeCl3) is the most common iron salt used to achieve coagulation. Its reactions in the coagulation process are similar to those of alum, but its relative solubility and pH range differ significantly from those of alum. Both alum and ferric chloride can be used to generate inorganic polymeric coagulants.
What is flocculation of soil?
Definition. Flocculation – process during which particles, for example, of a soil, dispersed in a solution contact and adhere each another, forming clusters, flocks, flakes, or clumps of a larger size. Flocculation is synonymous with agglomeration and coagulation.
How do you fix too much flocculant in a pool?
When you add too much clarifier to your pool mistakenly, the only way to get rid of it is to drain the pool and refill or you filter out the clarifier from the pool if you can. But you’ll have to take note of your filter’s pressure and media because too much clarifier can stick your pool’s DE/sand together.
How long does it take for flocculant to work?
How Long Does It Take to Work? The beauty of flocculants is that they work fast. Your pool can be cleaned in 24 hours, whereas with a clarifier, it takes a few days for the filter to do its job.
Is polymer a coagulant or flocculant?
Polymers (long-chained, high-molecular-weight, organic chemicals) are becoming more widely used. These can be used as coagulant aids along with the regular inorganic coagulants. Anionic (negatively charged) polymers are often used with metal coagulants.
How often can you use flocculant?
You can reuse a clarifier after 5-7 days, but if you’re constantly seeing cloudy water, there may be other problems. Adding too much flocculant can cause its own issues.
What is difference between flocculation and Deflocculation?
The key difference between flocculation and deflocculation is that flocculation is the formation of flocs by the clumping of fine particles, whereas deflocculation is the dispersion of flocs to form a stable colloid. Flocculation refers to the formation of clumps from fine particles in a colloid.
Can you drink flocculant?
In addition, coagulants and flocculants are expensive, which is why you want to avoid adding more than are necessary to the water; drinking water treatment plants use “jar tests” to identify the optimal coagulant and flocculant concentrations. Do not drink any of your water samples—even if they appear clear.
Why did the pH change in jar test?
If water contains no alkalinity, the pH changes dramatically because sulfuric acid is produced instead of CO2 as express in equation (2). Sulfuric acid is a strong acid that dissociate 100 % to proton, or H+.
How do I make my pool water crystal clear?
How to Make Your Pool Crystal Clear Again
- Keep Up with pH and Chlorine Levels. Do you have a water testing device in your supply kit?
- Run That Filter. It’s recommended that you run your filter for 8 to 10 hours a day when using your pool.
- Skim, Skim, Skim. Yes, something that simple can be the trick to clear water.
- Shock the Pool Once a Week.
Which gas is released when alum is added to water?
Explanation: Carbon dioxide gas is released when alum is added to water, which is corrosive to metals.
Is alum a coagulant or flocculant?
To accomplish this, the water is treated with aluminum sulfate, commonly called alum, which serves as a flocculant. Raw water often holds tiny suspended particles that are very difficult for a filter to catch. Alum causes them to clump together so that they can settle out of the water or be easily trapped by a filter.
What happens if agitation rate in flocculation phase is too high?
Stirring too fast can break large particles apart, while stirring too slowly can prevent particles from clumping enough. A wide variety of flocculation- mixing mechanisms have been used in water treatment.
Does flocculant kill algae?
There are two major chemical treatments for algae: flocculant and chlorine. Flocculant, or floc, is a chemical and mechanical process that works fast but requires work on your part. Then, you must turn it off to give the algae time to settle. If you use chlorine shock, you should run the filter almost continuously.
