View test prep what is the difference between coagulation and flocculation from civil engi vdb 2023 at petronas technology university. Coagulation is when particles come together irreversibly ie they get stuck together and cant be separated. On the other hand, if the mixing time is too short, the collisions between the flocculants and colloids are not efficient to precipitate suspended solids in wastewater. During flocculation, the solution is mixed gently, providing time and energy so the clumps will gather together and form larger clumps. Coagulation, flocculation and agglutination are terms that usually cause confusion. In the coagulation and flocculation solids processes,nonsettleable solids are converted into large and heavier settleables solids by physical chemical changes brought about by adding and mixing coagulant chemicals into the raw water. Definition of flocculation and classification of flocculants flocculation is the process by which the polymers polymer chains bridge between suspended particles.
There are several possible explanations for this difference in human nv and norovirus vlp. Coagulation and flocculation practices are essential pretreatments for many water purification systems in conventional coagulation flocculation sedimentation, a coagulant is added to the source water to create an attraction among the suspended particles. Bridge is the adsorption of different segments of polymer molecules on different particles to promote the aggregation of particles and particles. The term originates from the word floc, which is the flake of precipitate that comes out of solution. In addition to removing turbidity from the water, coagulation and flocculation process removes many bacteria which are suspended in the water and can be used to. 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. Coagulationflocculation process for produced water treatment. Improper coagulants make these treatment methods ineffective. Bridge is the adsorption of different segments of polymer molecules on different particles to promote the aggregation of. Flocculation occurs when either an anionic flocculant or a cationic flocculant forms a bridge between particles to make larger masses. Nov 09, 2018 coagulation mostly happens in a rapid mixing tank for a few minutes.
Coagulation and flocculation are an essential part of drinking water treatment as well as wastewater treatment. Suspended particles vary in source, charge, particle size, shape, and density. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Flocculation, in the field of chemistry, is a process in which colloids come out of suspension in. After coagulation the destabilized particles can collide, aggregate so flocs can be formed. Coagulation and flocculation process fundamentals 1 coagulation and flocculation. 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. Thus, the flocculation rate is not optimum under this condition. 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. Coagulation chemical treatment typically is applied prior to sedimentation and filtration to enhance the ability of a treatment process to remove particles. What is the difference between aggregation and coagulation.
Most water treatment practices including coagulation, flocculation and clarification, date back hundreds and in some cases thousands of years. In water treatment, coagulation is the result of the addition of chemical reagents to water suspensions where the dispersed colloidal particles are assembled in. Charge neutralization mechanism efficiency in water with. Material for this article was largely taken from reference 1. This water churning induces particles to collide and clump together into larger and more easily removable clots, or flocs. Agglutination occurs when an antibody forms in the blood, and bacteria, blood cells and other cells clump together to fight infections. Coagulation is the step where colloidal par ticles similar t o spheres of a diameter of less than 1 micrometer are destabilized. Apr 21, 2007 coagulation the transformation of liquid into jelly like semisolid mass. What is the difference between coagulation and flocculation.
Coagulation and flocculation water treatment waste water. Coagulation is the process of destabilization by charge neutralization. Coagulation and flocculation of industrial wastewater by chitosan. 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. They are typically used for treatment of wastewater containing colloids suspended particles and metal ions. Coagulation or flocculation of colloids pt i youtube.
Coagulation and flocculation are two main and important steps in drinking and wastewater treatment. Another type of tanks combine between flocculation and sedimentation in one tank and called solid contact flocculator clarifier. What is the difference between denaturation, coagulation. Using coagulants poly aluminum chloride and aluminum. The objective of this paper is to elucidate fundamental chemical differences existing between ec and cc that would impact coagulation mechanisms, flocculation behavior and subsequent floc characteristics. Groundwater and surface water contain both dissolved and suspended 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. Coagulation and flocculation processes are used to separate the suspended solids portion from the water. Therefore, a study was conducted on the effect of mixing time in flocculation. Flotation and flocculation underpin the key material supply chains for technologies that are central to minerals, fuel cells, ceramics, telecommunications, waste removalrecycling processes and many other. In flocculation one can make a distinction between perikinetic and. Coagulation, flocculation and clarification of drinking water. Similarities between coagulation and flocculation in. It is a timedependent process that directly affects clarification efficiency by providing.
Prospects and challenges of using coagulationflocculation. What is the difference between flocculation coagulation. Flocculation process commonly occurs under slow mixing conditions. The process requires chemical knowledge of source water characteristics to ensure that an effective coagulant mix is employed.
Once the ph adjusted, the same treatment of coagulation as above was used and initial and final absorbance and turbidity were measured. However, in flocculation the clumping stops before it becomes a continuous mass, a product observed in coagulation. Flocculation is the agglomeration of destabilized particles into microfloc and after into bulky floccules which can be settled called floc. Collision between particles during the coagulation process usually caused by brownian motion under rapid mixing. Coagulation vs flocculation in water treatment coagulation is an important step in. Flocculation is another important step in water treatment and it involves in the formation of visible flocs by mechanical or physical mixing. This article provides an overview of the processes and looks at the latest thinking. Coagulants and polymers the coagulation process includes using primary coagulants and may include the addition of coagulant andor filter aids. Collision between particles during the coagulation process usually caused by. In a second experiment, river water ph was adjusted at different phs between 4.
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. This can take place spontaneously or may be brought about by adding clarifying agents. Treatment processes coagulation coagulation coagulation. Colloidal particles colloids are midway in size1 between dissolved solids and. Coagulants neutralize the negative electrical charge on particles, which. Coagulation and flocculation are wellknown techniques within wastewater treatment. Coagulation, flocculation, sedimentation, and filtration a large portion of particles suspended in water can be sufficiently small that their removal by sedimentation or filtration is not practicable. Coagulationflocculation process for produced water. During this step, fibrinogen is converted to fibrin which forms a glue between other platelets bearing the receptor gpiibiiia. During coagulation, the coagulantalum are added to destabilize the surface charge of particles. Coagulation or flocculation of colloids pt i anand rai. Flocculation is gentle stirring or agitation to encourage. What is the difference between coagulation and agglutination.
In the flocculated system, there is no formation of. A polymer is added to the solution to strengthen the floc that formed, thus, reduced floc breakage and improved dewatering. The suspended particles vary considerably in source, composition charge, particle size. Flocculation is a physical process of contact and adhesions wherein the aggregates. Coagulation is a process to neutralize charges and then to. This haze can be dispersed buy first adding a coagulant. Various sizes of particles in raw water particle diameter mm type settling velocity 10 pebble 0. Ppt coagulation and flocculation linkedin slideshare. Some small watertreatment plants combine coagulation and sedimentation in a single. Engelhardt application development manager drinking water hach company photo by author the intent of this paper is to provide cursory information about coagulation, flocculation and clarification. Coagulation and flocculation are essential processes in various disciplines.
Flocculation flocculation refers to a process where a solute comes out of solution in the form of floc or flakes. The particles that form floc are often feathery in appearance. The processes of flocculation, sedimentation, and filtration should be used with coagulation to reduce suspended solids and turbidity. Coagulation refers to a blood clot that forms because of an open wound or from cholesterol within blood vessels. 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. They have explained the correlation between particle size and flocculent molecular weight in terms of floc. Imagine it as your arms are gpiibiiia receptors and your legs are bound to. Coagulation and flocculation anup ghimire, rock face limited 2. This is the key difference between coagulation and flocculation. The difference between these two categories is as follows. A variety of flocculants and coagulants is available, with different chemistries, molecular weights, charge ratios, and other attributes. The process of agglomeration of the destabilized particles to such a size that separation by sedimentation and filtration is possible.
The term is also used to refer to the process by which fine particulates are caused to clump together into floc. Flocculation and dispersion phenomena in soils springerlink. In contrast, in flocculation, the destabilization is brought about by physical techniques such as mixing of the solution, and also sometimes by the addition of polymers. For example, two spheres coalesce to form one larger sphere. Coagulation and flocculation in water and wastewater. Enhanced removal of heavy metals in primary treatment using coagulation and flocculation pauline d. Emulsions of proteins, carbohydrates and fats can be transformed into removable flocs by means of coagulation destabilisation and flocculation conglomeration of destabilised particles. The steps in coagulation are activation, adhesion and aggregation. Removal is generally accomplished by coagulation, flocculation, and sedimentation.
The process yields particles that are visible to the naked eye, unlike coagulation which yields microscopic microflocks. The term flocculation is often confused with coagulation. Coagulation is the destabilization of colloidal particles brought about by the addition of a chemical reagent called as coagulant. Coagulation, flocculation, sedimentation, and filtration. 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. Despite the drastic variations in such kind of field. Flocculation i flotation flotation, using micro air bubbles, removes suspended solids as well as free oil, fat and grease. Most of these small particles are negatively charged, which is the major cause of the stability of suspended soil particles. Coagulation involves the use of a coagulant which has the potential to destabilize the previously stabilized charged particles in the suspension. The efficiency of coagulation flocculation strongly affects the overall treatment performance. Solidscontact units often combine clarification and precipitation softening.
Aluminum sulfate alum is the most common coagulant used for water. Water supply system coagulation and flocculation britannica. Optimize phosphorus and turbidity removal from secondary effluent kun yang 430. The settleable solids can then be removed by the sedimentation and filtration processes. This enables their removal by sedimentation, dissolved air flotation or filtration. Coagulation is a process of making colloidal matter dispersedsuspended in a liquid to join in a coherent mass. The optimum ph for the coagulation and flocculation process must be determined experimentally. Ozoneflotation obtained better water quality results than. Methods of coagulation part 18cbse grade 12 chemistry. Flotation and flocculation from fundamentals to applications. It is critical that the appropriate flocculant andor coagulant be. These data indicate that tissue factor is absolutely required for hemostasis. Comparison between coagulationflocculation and ozone.
Safe drinking water is essential coagulationflocculation. Its a preference in the primary purification processes due to its simplicity operation, efficient and cheap. Flocculation is the snowballing of sm all particles into larger particles called floc. Flotation and flocculation deals with cuttingedge research in the science and engineering of two of the worlds key separation processes. Pdf waste water treatment by coagulation and flocculation. Coagulation and flocculation consist of adding a floc forming chemical reagent to a water to enmesh or combine with nonsettleable colloidal solids and slow. What is the difference between coagulants and flocculants. Coagulation, flocculation and clarification of drinking water terry l. The floc may float to the top or settle to the bottom of the liquid, as well can be readily. But the phenomena are also wellknown from everyday life especially coagulation. Flocculation flocculation is the next step in most treatment plants inline filtration plants being the exception. Earthen jars used to store water it is good to keep water in copper vessels, to expose it to sunlight and.
Difference between coagulation and flocculation in water. Coagulation refers to clotting of the blood and forming clots or large clumps. Pdf coagulationflocculation process for produced water. Meanwhile, the removal of nv by coagulation, flocculation and sedimentation processes in this study 1. The key difference between coagulation and flocculation in water treatment is that the coagulation is a chemical process while flocculation is a physical process. 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. These anionic and cationic flocculants are long chains of acrylamide. Oct 23, 2017 flocculation is a process in chemistry wherein colloids are extracted from suspensions which then take the form of flake or floc. Flocculation flocculation is the next step in most. Flocculation is similar to coagulation in that both refer to smaller particles clumping together to form larger particles. Their objective is to enhance the separation of particulate species in downstream processes such as sedimentation and filtration. Coagulation is a process to neutralize charges and then to form a gelatinous mass to trap or bridge particles thus forming a mass large enough to settle or be trapped in the filter.
Coagulation and flocculation constitute the backbone processes in most water and advanced wastewater treatment plants. The addition of another reagent called flocculant or a flocculant aid may. For instance, denaturing an enzyme means the enzyme can no longer carry out its function. In biochemistry, denaturation is the abolishing of the properties of a molecule. Flocculation is the process of creating conditions for particulates to come together to form flocs of solids and then settle in treated water. Optimize phosphorus and turbidity removal from secondary effluent kun yang. The primary purpose of the coagulation and flocculation is to destabilize the charged colloidal particles in water and make them to settle so as to remove turbidity from the water. Thus, chemical dosing which is not optimal means that the conditions for coagulation are not the optimum. This knowledge will provide a basis for understanding the needs of the.
Similarities between coagulation and flocculation in water treatment. Enhanced removal of heavy metals in primary treatment. Both processes involve the union of different suspended particles together. The art of flocculation and coagulation has a lot more science than meets the eye. Eve 290l introduction to environmental engineering laboratory. During coagulation, chemicals are added to make particles clump together. Blood clots also form when blood fails to flow properly in the body. Dec 26, 2019 the solidscontact process upflow clarifiers combine the coagulation, flocculation, and sedimentation processes into a single basin. What is the exact differences between coagulation and. Ene 806 project report 2 coagulation and flocculation. Mar 31, 2016 3312016 2 why coagulation and flocculation. Coagulation and flocculation tu delft opencourseware. Coagulation and flocculation are used to separate the suspended solids portion from the water. These forces are encouraged through increased retention time and decreased mixing energy.
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