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The deflocculating action is carried out by an increase in pH, but the carbonate ion, before hydrolysis, can react with calcium ions that may be present in the solution, thereby forming CaCO3 which is insoluble and therefore a flocculating element is removed from the suspension.
What does adding a Deflocculating agent do?
The addition of a deflocculating agent to a soil-water mixture affects the degree of dispersion of the soil sample and may also affect the specific gravity of the soil particles and the viscosity and specific gravity of the suspending medium. 001 mm. , the higher the degree of dispersion.
What are Deflocculating agents?
An agent that prevents fine soil particles or clay particles in suspension from coalescing to form flocs. Synonym of: deflocculant, dispersing agent.
Is Epsom salts a Deflocculant?
Epsom salts are my flocculant of choice. To use Epsom salts as a flocculant, the salts need to be dissolved in water. This breaks up the bond between the magnesium and the sulphate so the magnesium ions are free to attach themselves to the clay particles.
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.
How do hydrometers work?
How Do Hydrometers work? Hydrometers use displacement to calculate the density and specific gravity of a liquid. When the hydrometer is placed in a liquid sample, it displaces some of the liquid. The volume of liquid that is displaced is then used to measure its density.
How does a Deflocculant work?
Deflocculants are electrolyte-sourcing liquids or powders (like sodium silicate, Darvan) that are added in small amounts. They work their magic by imparting electrical charges to clay particles making them repel each other (more accurately it is said to be a condition where repulsive forces predominate).
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 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.
Why is hydrometer test important?
A hydrometer analysis is the process by which fine-grained soils, silts and clays, are graded. The hydrometer also determines the specific gravity (or density) of the suspension, and this enables the percentage of particles of a certain equivalent particle diameter to be calculated.
What is coagulant and flocculant?
Coagulation and flocculation are used to separate the suspended solids portion from the water. Suspended particles vary in source, charge, particle size, shape, and density. Coagulation and flocculation occurs in successive steps, allowing particle collision and growth of floc.
Which are the flocculating agents in soil?
In soils, the flocculation process concerns mostly the clay particles present. Clay particles usually possess net negative charge and therefore they electrostatically attract positively charged ions, such as Ca2+ cations, which form bridges, holding the particles together.
Is Redisperse difficult?
The repulsive forces between individual particles allow them to slip past each other as they sediment. The slow rate of settling prevents the entrapment of liquid within the sediment, which thus becomes compacted and can be very difficult to redisperse.
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 is the other name of Deflocculation?
What is another word for Deflocculation? flocculation. deflocculation and flocculation. coagulation.
How does vinegar affect clay?
The acidity of the vinegar breaks down the clay a bit, and makes it sticky. Some artists use vinegar straight from the bottle, or add vinegar to clay instead of water to make a joining slip. All these methods work to create a join that is stronger than water or slip alone.
Is CMC a Deflocculant?
Na-cmc is a powerful binder. It is a member of the carbohydrate binder group–the binder group with the strongest binding power. It is capable of acting as a deflocculant in glazes and nonclay casting slips.
Why do Flocculated particles not cake?
Repulsive forces between particles are overcome and a hard cake is formed which is difficult, if not impossible, to redisperse. The sediment is loosely packed and possesses a scaffold-like structure (large volume of final sediment). Particles do not bond tightly to each other and a hard, dense cake does not form.
What is hydrometer analysis used for?
In geotechnical engineering, hydrometer analysis is primarily used to know the grain size distribution of a fine grained soil.
What is CU and CC?
Uniformity Coefficient(Cu) and Coefficient of Curvature(Cc) of Soil. The uniformity coefficient (Cu), curvature coefficient (Cc) and the effective size (D10) are the grading characteristics of the soil. These are the geometric properties of a grading curve that describe a particular type of soil.
What causes Deflocculation?
In dispersed clay slurries, flocculation occurs after mechanical agitation ceases and the dispersed clay platelets spontaneously form flocs because of attractions between negative face charges and positive edge charges.
Is Vinegar a Deflocculant?
Vinegar is often used in ceramic slurries to change the viscosity (thicken it). While there are more effective flocculants (e.g. calcium chloride, epsom salts), vinegar is popular among potters simply because it is so available.
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.
What properties should a well formulated suspension possess?
A good suspension should have well developed thixotropy. At rest the solution is sufficient viscous to prevent sedimentation and thus aggregation or caking of the particles. When agitation is applied the viscosity is reduced and provide good flow characteristic from the mouth of bottle.
