Collodialcharacteristics classificationof collodialsolids in wateracc. Agglutination and coagulation are two very technical terms which rarely come up unless you are a medical professional. Near the border of the particle there is a chargefree space, called the sternlayer. Dec 26, 2016 difference between coagulation and flocculation type of process. Coagulation, flocculation and precipitation youtube. Study on the factors affecting coagulation and flocculation. The flocculant is often a polymer which induces the settling of particles and eventually grows into larger flake. In flocculation one can make a distinction between perikinetic and.
Correct application of coagulation and flocculation depends upon these factors. Coagulation, flocculation and agglutination are terms that usually cause confusion. What is the difference between coagulation and flocculation. Precipitation is the process of forming insoluble solid mass from the reaction of ions present in a solution.
The prevailing mechanism is thus adsorptive coagulation. Brownian flocculation of polymer colloids in the presence. The coagulant is often a salt and breaks down to release charges. In this paper, results are reported that show the interaction between primary and secondaryminimum flocculation when the interparticle potential curve reflects both attractive and electrostatic repulsive forces. Flocculationflocculation refers to a process where a solute comes out of solution in the form of floc or flakes.
What are the differences between flocculant and coagulant. Aug 30, 2015 flocculation process where colloids come out of suspension in the form of floc or flake due to. The floc is subsequently removed in most cases by sedimentation. It is specific to each application and is dependent upon the sample, the coagulation and flocculation agents used, the desired clarity of the water, and the waters end use. Coagulation and flocculation are two main and important steps in drinking and wastewater treatment. Flocculation is similar to coagulation in that both refer to smaller particles clumping together to form larger particles.
It has been shown that both mechanisms can give suspensions which are readily redispersible but that flocculation may produce pharmaceutically undesirable effects. Coagulation and flocculation mechanisms have been examined in suspensions of the drug griseofulvin containing anionic surfactants. Properties that made them stay in suspension are removed. Coagulation and flocculation in suspensions of griseofulvin.
Coagulation and flocculation are an essential part of drinking water treatment as well as wastewater treatment. Difference between agglutination and coagulation compare. Flocculation, in the field of chemistry, is a process in which colloids come out of suspension in the form of floc or flake, either spontaneously or due to the addition of a clarifying agent. Pdf the aim of this paper is to provide an overall description of coagulation flocculation process and its applications in water and wastewater. The suspended particles vary considerably in source, composition charge, particle size, shape, and density. Turbidity can be classified as being anionically charged silica particles. The action differs from precipitation in that, prior to flocculation, colloids are merely suspended in a liquid and not actually dissolved in a solution. Pdf comparative study between flocculationcoagulation. Simulation of the coagulation and flocculation steps in the water treatment process let the water settle after flocculation and settling, sample the settled. Microscale flocculation the flocculation of small particles less than 0. Often the effect that turbidity has is dependent on the amount present rather than the classification.
Difference between agglutination and precipitation definition. Rapid mixing of the water and coagulant is important to ensure thorough and even distribution. Collodialcharacteristics colloidaldispersions solidsdispersedin liquids sols e. Is only a measure of how much light passes through water. Both processes involve the union of different suspended particles together. However, in flocculation the clumping stops before it becomes a continuous mass, a product observed in coagulation. Further suspended matter in the water is then attracted to the flocs. Coagulation is a process of making colloidal matter dispersedsuspended in a liquid to join in a coherent mass. What is the exact differences between coagulation and. Coagulation and flocculation phenomena coagulation is known as the process of destabilization of colloids. The design flow for a water treatment plant wtp is 1 mgd 3. Dec 10, 2017 the key difference between coagulation and flocculation in water treatment is that the coagulation is a chemical process while flocculation is a physical process. Start studying coagulation, flocculation, sedimentation, and filtration.
Difference between coagulation and flocculation in water. In low turbidity waters coagulation destabilises particles through chemical reaction between coagulant and colloids, and flocculation transports the destabilised particles that causes collisions with flocs. Amongst the 800 different flocculants of the flopam range, two main categories of flocculants can be distinguished. Flocculation process where colloids come out of suspension in the form of floc or flake due to. An evident difference between the adsorptive and precipitation. The key difference between coagulation and flocculation in water treatment is that the coagulation is a chemical process while flocculation is a physical process. Earthen jars used to store water it is good to keep water in copper vessels, to expose it to sunlight and. Coagulation and flocculation in water and wastewater. Thus, the primary mechanism of aggregation is through brownian motion. Pdf waste water treatment by coagulation and flocculation.
Correct application of coagulation and flocculation processes and selection. The potential difference between the plates is v and the space between the plates is of. Difference between coagulation and flocculation type of process. Flocculation is commonly confused with coagulation, and the terms are consequently used to some extent interchangeably but they are very different processes.
Collision between particles during coagulation process usually caused by brownnian. Flocculation flocculation refers to a process where a solute comes out of solution in the form of floc or flakes. Difference between agglutination and precipitation. Groundwater and surface water contain both dissolved and suspended particles. Coagulation is an important step in water treatment and it involves in the addition of a coagulant to enhance the clotting of suspended particles in water.
The optimum ph for the coagulation and flocculation process must be determined experimentally. Coagulation is achieved by neutralizing the particles and thus, the repelling force between the particles is greatly reduced. The starting material for agglutination are the particles present in the. Flocculation is synonymous with agglomeration and coagulation coalescence. The basic mechanism of destabilization is removing the electrical charge. For the love of physics walter lewin may 16, 2011 duration. Coagulationflocculation process for produced water treatment. Another type of tanks combine between flocculation and sedimentation in one tank and called solid contact flocculator clarifier. The rate of flocculation is relative to the rate at which the particles diffuse. The term is also used to refer to the process by which fine particulates are caused to clump together into floc. Essentially, a coagulant is added to water in order to gather any waste in the water such as dust, earth particles, fish eggs, etc. Coagulation vs flocculation in water treatment coagulation is an important step in. After employing the flocculation process, the coagulated particles form a large agglomeration, which is also known as. Material for this article was largely taken from reference 1.
Pdf coagulationflocculation processes in waterwastewater. Hydrophobic colloids are charged particles surrounded by a cloud of opposite and equally charged ions g. The rapid mixing tank will have a mechanical mixer and the average alum dosage will be 30 mgl. The theoretical mean hydraulic detention time of the tank will be 1 minute. Agglutination is the process of forming a solid mass from particles present in a solution. On the other hand, flocculation means to form flocs. These particles form clumps with the help of a coagulant.
Coagulation and flocculation process fundamentals 1 coagulation and flocculation. Flocculation is another important step in water treatment and it involves in the formation of visible flocs by mechanical or physical mixing. Metal salts hydrolyze rapidly in waste water to form cationic species, which are adsorbed by negatively charged dirt. Coagulation mostly happens in a rapid mixing tank for a few minutes. The differences between the two phenomena are discussed. What is the difference between coagulation and flocculation in water treatment. Suspended particles vary in source, charge, particle size, shape, and density.
Similarities between coagulation and flocculation in. Correct application of coagulation and flocculation processes and selection of the. The coagulationflocculation cf processes are mainly due to charge neutralisation cn and sweep flocculation sf mechanisms. Most water treatment practices including coagulation, flocculation and clarification, date back hundreds and in some cases thousands of years. Coagulation and flocculation tu delft opencourseware.
Coagulationflocculation process for produced water. Brownian flocculation of polymer colloids in the presence of. After coagulation the destabilized particles can collide, aggregate so flocs can be formed. Coagulation and flocculation coagulation and flocculationconsist of adding a flocforming chemical reagent to a water to enmesh or combine with nonsettleable colloidal solids and slowsettling suspended solids to produce a rapidsettling floc. The density difference between water and the particles produced in water treatment by coagulation, flocs, in general is small. In a second experiment, river water ph was adjusted at different phs between 4. Colloidal particles colloids are midway in size1 between dissolved solids and. Basically, coagulation is a process of addition of coagulant to destabilize a stabilized charged particle. Pdf in this study is present the advantages and disadvantages of the use of. Coagulationflocculation treatment of municipal wastewater. During coagulation, the coagulantalum are added to destabilize the surface charge of particles. Apr 21, 2007 coagulation the transformation of liquid into jelly like semisolid mass. Ene 806 project report 2 coagulation and flocculation. Coagulation and flocculation provide the water treatment process by which finely divided suspended and colloidal matter in the water is made to agglomerate and form flocs.
Learn vocabulary, terms, and more with flashcards, games, and other study tools. Coagulationthe transformation of liquid into jelly like semisolid mass. Meanwhile, flocculation is a mixing technique that promotes agglomeration and assists in the settling of particles. The process of agglomeration of the destabilized particles to such a size that separation by sedimentation and filtration is possible. May 10, 2014 agglutination and coagulation are two very technical terms which rarely come up unless you are a medical professional. Agglutination is the process of clumping of particles. The present study is on the performance of coagulation and ballast flocculation. Improved jar testing optimization with toc analysis. Nov 09, 2018 coagulation mostly happens in a rapid mixing tank for a few minutes. Suspended particles vary in source, charge, particle size, shape. In the flocculated system, there is no formation of.
The addition of a chemical coagulant to the water causes the formation of a precipitate, or floc, which entraps these impurities. The coagulation flocculation cf processes are mainly due to charge neutralisation cn and sweep flocculation sf mechanisms. Download the pdf version of coagulation vs flocculation in water treatment. Coagulation and flocculation are used to separate the suspended solids portion from the water. Coagulation and flocculation processes are used to separate the suspended solids portion from the water. Doesnt distinguish between inorganic, organic, particulates. This article provides an overview of the processes and looks at the latest thinking. This enables their removal by sedimentation, dissolved air flotation or filtration. Coagulationflocculation treatment is commonly used to reduce the turbidity of municipal and industrial waste water, the coagulants in question typically being divalent or trivalent metallic salts or polymers that have low solubility in the ph range used. Hydrophobiccolloids havelittleaffinityforwater amino, carboxyl, sulfonic, hydroxyletc. Thus, coagulation and flocculation techniques are employed for separating these impurities from water. Difference between coagulation and flocculation coagulation. Comparative study between flocculationcoagulation processesin raw wastewater treatment. This aggregation is called microscale flocculation or perikinetic flocculation.
Flocculation is a physical process in which the fine solids produced by coagulation are brought together into larger particles using controlled low levels of shear. This aggregation is called microscale flocculation or. On the interface between the strenlayer and the diffuse layer there is. Flocculation process commonly occurs under slow mixing conditions. Apr 27, 2016 042716 water treatment 59 g value for coagulation. Flocculation is a physical process in which the fine solids produced by coagulation are brought together into. On the interface between the strenlayer and the diffuse layer there is zeta potential.
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