Hydrocyclone

Hydrocyclone, often abbreviated as cyclone, is a device for sorting, separating, or classify particles in a liquid suspension with their centrifugal force or liquid resistance ratio.

This ratio for dense particles (where density separation is used) and coarse particles (where size separation is performed) and low for light and fine particles mostly is low. Hydrocyclones are also used to separate liquids with different densities in many application.

definitions
A hydrocyclone is a mechanical device used to reduce or increase the concentration of a phase, solid, liquid or gas of varying densities, using a centrifugal force or a centrifugal force with a rotating, eddy motion. .

The mixture enters or injected into the hydrocyclone, and when it is injected with a rotating or vortex motion to disperse the centrifugal acceleration using the two-phase relative density and move to the vortex core.

Usually, hydrocyclones have a cylindrical part on top of which the liquid mixture is injected tangentially. Below this section, there is a conical base section. What determines the operating characteristics of hydrocyclones is the length of the camshaft cone layer, which has a great impact on the separation process.

Design

The overall design of the hydrocyclones is a classifier with one axis and two outputs in the axis. At the bottom of this separator, one of these outlets is embedded, which is to discharge underflow or to reject the fluid. At the top is another of these outlets intended for insertion into the s overflow or accept the liquid.

In fact, the lower liquid flow is mainly due to the reduction of larger or denser particles, and the liquid supernatant is mainly used to reduce or subtract smaller and lighter particles. This structure has no moving parts and its performance depends on two main parameters:

• Inlet or feed flow specifications (inlet fluid)
• Cyclone geometry

Specifications relating to the flow of fluid or inlet fluid include such matters as the size of solids present in the liquid regrowth, the pulp density (percentage of solids present in the sludge or liquid required for filtration), the pulp viscosity as well as the inlet pressure used to separate solids from the liquid.

In a liquid or liquid feed stream such as in oily water, the main characteristics of the feed are determined by the size and distribution of the oil droplets in the water, oil density, water density, oil concentration, viscosity and temperature.

Cyclone geometry includes the shape and area of the inlet, the dimensions of the silicon (such as cone angle, cylindrical cross-section length and total silicon length), inlet diameter, vortex, and surface area or height.

In terms of internal, inertia, and constant structure, it is resistant to liquid, with the exception that larger and denser particles move under the flow with a small amount of liquid to reach the final stage of silicon removal. The particles remain lighter and finer, with a lower density, and are ejected from the liquid supernatant around a tube embedded in the silicon body in the center of its orbit.

Forward hydrocyclones eliminates particles that are thicker than the surrounding fluid, while reverse hydrocyclones eliminates particles that are less dense than the surrounding fluid.

In reversed hydrosilicon the overflow is at or above the current and the underflow is at the base of the current. There are also parallel-flow hydrocyclones that remove both accept and the reject current on the flow surface.

As a result, parallel-flow hydrocyclones are able to remove lighter particles from the surrounding fluid well.

Hydrocyclones can be made from materials such as metal that is often steel, ceramic or even plastics such as polyurethane, polypropylene or other types. Metal and ceramic hydrocyclones are commonly used in situations where there is a need for greater resistance both to heat and to circuit pressures.

If there are particles that cause abrasion or abrasive effects (such as sand or sand particles in the liquid), it is better to use polyurethane types, which performs better than metals or ceramics. In cases where both hybrid abrasion and high pressure are present, usually clad hydrocyclones are used.

When suspending particles of the same concentration and density, a relatively sharp cut could be employed. The size of the particles being separated can be a function of the cyclone’s diameter, output dimensions, feed fluid pressure, and the relative properties of the particles and the liquid.

The efficiency of particle separation is generally a function of the concentration of solids in the liquid: the higher or more solids concentration, the lower and slower the separation efficiency.

There is also a significant difference in the density of suspension between the base output (for lighter and fines particles) and the upper or apex output for the larger and heavier particles, where there is less fluid.

If the particle size range is limited, but there is a difference in the particle concentration due to the nature of the particles, the thicker and denser particles usually exit the upper or apex exit. Therefore, the device in general can be a means of selecting concentrations of substances or liquids such as minerals.

The device also relies on a centrifuge, both of which work as centrifuges using centrifugal force to separate particles heavier and lighter than liquids.

By rotating the entire equipment, Centrifuges generate the separation force, and the hydrocyclones use centrifugal force to move the fluid to perform separation.

Design equations

Generally for a Bradley hydrocyclone, in the same proportions for each part, the dimensions are always considered. The pressure drop is considered to be between 20psi and 60 psi.

Accordingly, the following equations are significant:

• Di represents the inner diameter
• Do shows the diameter of the overflow current
• Du represents the diameter of the underflow current
• Dc describes the diameter of the chamber
• L indicates the height or tall of the hydrocyclone
• l indicates the height or tall of the hydrocyclone cylinder part
• ℓ indicates the height or tall of the vortex tube
• Le represents the outer height of the tube
• Theta represents the base angle of the hydrocyclone
• In / Dc = 1/7
• Do / Dc = 1/5
• Du / Dc = –
• L / Dc = –
• l / Dc = ½
• ℓ / Dc = 1/3
• Theta = 9 degrees

Uses

Generally, hydrocyclones are devices used to separate heavy loads from a liquid mixture at a centrifugal pump or some compressed and sequential fluid sources under pressure or two-phase (gas-liquid) systems.

Hydrocyclones are likely to be a good choice for processes where lighter particles make up a larger portion of the liquid mixture and the heavier particles are smaller.

Hydrocyclones are usually used in continuous flow systems because the instantaneous liquid flow to hydrocyclone is equal to the total assembly of all lighter particles out of the flow plus heavier particles. If the higher-weight particles contain less of the entire liquid, the best way is to collect all of these particles on the floor of the hydrocyclones, and in order to remove them from the liquid, they will be aggregated as a single mass, as a batchwise Remove

Hydrocyclones are generally used for applications in the following industries:

• In the potato starch, cassava, wheat and corn starch industries for the purpose of both concentrating and washing crude starch milk. In these industries, hydrocyclones are used as a more expensive and efficient method of separation than conventional separators.
• Hydrocyclones are used in the paper mills industry and in cartons and paper mills to remove sand, staples, plastic particles and other contaminants.
• In the drilling industry, hydrocyclones are also used to separate sand from expensive clay, which is used for lubrication during drilling.
• In the oil industry, hydrocyclones are used to separate oil from water or vice versa.
• In the metalworking industry, hydrocyclones are used to separate metal particles from the coolant.
• For the production of French fried potatoes or potato chips, hydrocyclones are used to retrieve starch in the water line and from waste water.
• In the mineral processing industry, hydrocyclones are widely used for various purposes to classify particles for rotation in a grinding or abrasive system and to differentiate between economical minerals and worthless clumps.
• In the irrigation industry, hydrocyclones are also used to remove sand and silt from the water used for irrigation and for drip irrigation.