Table of Contents
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. The term originates from the word “floc,” which is the flake of precipitate that comes out of solution.
What is meant by flocculation?
Flocculation is a process by which a chemical coagulant added to the water acts to facilitate bonding between particles, creating larger aggregates which are easier to separate. The method is widely used in water treatment plants and can also be applied to sample processing for monitoring applications.
What is flocculation in ecology?
Flocculation is a process by which particles come out of the suspension to form flocs or larger particles, specifically in an estuarine environment. The flocculation process is influenced by physical, chemical, and biological factors in both terrestrial and aquatic environments.
How does a flocculant work?
A flocculant is a chemical that can be added to the water to help colloids and any other suspended solids bind together and form heavier particles. The heavier particles then settle to the bottom of the container/tank and the water on the top is drained off.
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.
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 an example of flocculation?
Flocculation and coagulation treatment chemicals are used in effluent wastewater water treatment processes for solids removal, water clarification, lime softening, sludge thickening, and solids dewatering. Examples of ChemTreat coagulation products include aluminum salts, iron salts, and polyelectrolytes.
Which ion causes dispersion in soil?
When the ratio of sodium to other ions at these exchange sites is high, clay particles are less tightly bound to each other and the soil aggregates easily disperse when the soil becomes wet.
What chemical is used for flocculation?
Coagulants such as alum (Al2(SO4)3-14H2O), iron salts (ferric chloride (FeCl36H2O), ferric sulfate (Fe2(SO4)3) and ferrous sulfate (FeSO47H2O)), lime (Ca(OH)2) and organic polyelectrolytes are used as flocculation aids during wastewater treatment.
What is flocculant made of?
Aluminum sulfate or alum (Al2(SO4)3), ferric chloride (FeCl3) and ferric sulfate (Fe(SO4)3) are the most widely used flocculants [1, 70]. These flocculants have a long history of use in removing colloidal particles from water and wastewater [15, 17].
Can you add too much flocculant?
Too much floc can detract from the beauty of your pool. Flocculants are substances that help clear the cloudiness and restore the clarity to your swimming pool water. You can use too much floc, however.
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.
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.
Which soil is not treated with gypsum?
Now that we have ascertained what gypsum is, it’s natural to question, “Is gypsum good for the soil?” Since it reduces salt levels in soil, it is effective in coastal and arid regions. However, it doesn’t work in sandy soils and it can deposit an excess of calcium in regions where the mineral is already abundant.
What causes flocculation in soil?
Soil particles will flocculate if the amount of soluble salts in the soil is increased (increased EC), even if there is a lot of sodium. Soil particles may disperse if the amount of soluble salts in the soil is decreased (i.e. if EC is decreased).
Which are the flocculation agent in soil?
Sodium silicate is specified as the de- flocculating agent in the present ASTM and AASHO standard methods of mechanical analysis. Sodium pyrophosphate and so- dium metaphosphate have been found ef- fective as deflocculating agents lor many types of soil (1, 5, 6).
Is flocculation good for soil?
In all but the sandiest soils, dispersed clays plug soil pores and impede water infiltration and soil drainage. Flocculation is important because water and oxygen moves mostly in large pores between aggregates moves mostly in large pores between aggregates. Also, plant roots grow mainly between aggregates.
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 the purpose of flocculation?
Effect on Turbidity As with coagulation, the purpose of flocculation is not to directly reduce turbidity or suspended solids, but to prepare the solids for subsequent removal. Flocculation reduces the number of suspended solids particles as smaller particles combine to form larger ones.
What is the difference between flocculant and coagulant?
Flocculants differ from coagulants in that they are often polymers, whereas coagulants are typically salts. Generally speaking, anionic flocculants are used to catch mineral particles while cationic flocculants can capture organic particles.
Is flocculant harmful to animals?
Aquatic toxicology Generally, cationic flocculants have been found to be most toxic to fish but this varies for crustaceans. Flocculants appear to act mainly by acute toxicity, probably by physical blocking and mucous production of gill tissue and sorption to small invertebrates (Biesinger et al.
How is flocculation prevented?
Design contact times for flocculation range from 15 or 20 minutes to an hour or more, and flocculation requires careful attention to the mixing velocity and amount of mix energy. To prevent floc from tearing apart or shearing, the mixing velocity and energy are usually tapered off as the size of floc increases.
