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Flocculation is synonymous with agglomeration and coagulation / coalescence. Basically, coagulation is a process of addition of coagulant to destabilize a stabilized charged particle. Meanwhile, flocculation is a mixing technique that promotes agglomeration and assists in the settling of particles.
What is meant by coagulation and flocculation?
Coagulation-flocculation: The use of chemical reagents to destabilise and increase the size of the particles; mixing; increasing of flog size, A physical separation of the solids from the liquid phase. This separation is usually achieved by sedimentation (decantation), flotation or filtration.
What is the difference between flocculation and agglutination?
The precipitins might either remain suspended or settle down towards the bottom. In flocculation, the flocculants float on the surface of the liquid matrix. The starting molecules in agglutination are particles. The starting molecules in precipitation are ions.
What does coagulation mean?
Coagulation is defined as the change in the structure of protein (from a liquid form to solid or a thicker liquid) brought about by heat, mechanical action or acids. Enzymes may also cause protein coagulation e.g. cheese making.
What are the 2 stages of agglutination?
These reactions take part in two stages, sensitization and agglutination. In the first stage (sensitization), the antibody binds to the red cell or sensitizes it. In the second stage, the sensitized red cells agglutinate. Although sensitization occurs first, it and agglutination ultimately overlap to some extent.
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.
What is the difference between flocculation and precipitation?
Flocculation and precipitation form large solid mass out of small masses. Precipitation is the process of formation of an insoluble solid mass. The main difference between flocculation and precipitation is that flocculation forms floccules whereas precipitation forms precipitates.
What is a flocculation test?
A Flocculation Test Procedure is used to determine how much Flocculants need be added to solids in suspension (slurry or pulp) to cause the individual particles to collect in the form of flocs. The formation of flocs aids in improved settling rates, better overhead clarity and/or faster filtration rates.
What is meant by flocculation?
Flocculation is a process whereby small particles in suspension are caused to aggregate, giving large clusters (flocs) that are much more easily separated than the original particles. The process is in widespread use in many industrial applications.
What causes coagulation?
Blood vessels shrink so that less blood will leak out. Tiny cells in the blood called platelets stick together around the wound to patch the leak. Blood proteins and platelets come together and form what is known as a fibrin clot. The clot acts like a mesh to stop the bleeding.
Are coagulants and flocculants the same?
Coagulants achieve flocculation through charge neutralisation whereas flocculants physically bind clay and colloidal particles together. The use of natural and synthetic polymeric flocculants can be used to generate larger, more stable flocs and may reduce treatment times.
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.
Which is not a example of coagulation?
Rubber plating and chrome tanning.
Which one is a good coagulant?
Aluminum and iron salts are the most commonly used inorganic coagulants in the wastewater treatment settings. These include based aluminum metals (aluminum chloride, aluminum sulfate, sodium aluminate) and iron based metals (ferrous sulfate, ferric sulfate, ferric chloride) [13, 17, 18].
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 chemicals are flocculants?
A flocculants are usually organic chemicals added to wastewater to enhance flocculation, such chemicals are alum, aluminium chlorohydrate, aluminium sulphate etc.
What is an example of coagulation?
Examples of Coagulation Milk proteins coagulate to thicken the mixture that forms yogurt. Blood platelets coagulate blood to seal a wound. Pectin gels (coagulates) a jam. Gravy coagulates as it cools.
What is the function of coagulant?
In water treatment, coagulants are used to remove a wide variety of hazardous materials from water, ranging from organic matter and pathogens, to inorganics and toxic materials, like arsenic, chemical phosphorous and fluoride.
What foods use coagulation?
Coagulation is used in food preparation most commonly for cooking eggs, some examples include; raw eggs being cooked eg boiled or scrambled as part of a dish, making a quiche with coagulated eggs, meringue (denaturation for beating the eggs, coagulation for cooking the egg product), pretty much any egg product being Mar 14, 2014
Why agglutination is dangerous?
The agglutinated red cells can clog blood vessels and stop the circulation of the blood to various parts of the body. The agglutinated red blood cells can also crack open, leaking toxic contents out in the body, which can have fatal consequences for the patient.
What is coagulation in food?
Coagulation is defined as the transformation of proteins from a liquid state to a solid form. Once proteins are coagulated, they cannot be returned to their liquid state.
Which coagulant is best?
A metal based coagulant will consume alkalinity, especially in a well buffered high pH water, which could compromise the softening process. The best coagulant is therefore a pre-hydrolysed species with a high basicity. PACl has been found to be very suitable for lime softening applications.
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.
What is the principle of coagulation?
Coagulation and flocculation are related terms describing the process of preparing colloidal materials for removing by sedimentation. Coagulation is the process used to reduce the energy forces present around particles that tend to keep them from joining together to form a larger mass.
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.
