CONTENT
CENTRIFUGE
INTRODUCTION
CENTRIPETAL
FORCE
CENTRIFUGAL
FORCE
CENTRIFUGE SEPARATION
PURPOSE
OF SEPARATION
SEPARATION
PROCESS
PURIFIER
CENTRIFUGE INTRODUCTION
Centrifugation is a method of separating molecules having different densities by spinning them in solution around an axis (in a centrifuge rotor) at high speed. It is one of the most useful and frequently employed techniques
CENTRIPETAL & CENTRIFUGAL FORCEs
Centripetal force is defined as, “The actual force (inertia of motion), the component of force acting on a body in curvilinear motion that is directed toward the center of curvature or axis of rotation,”
Centrifugal force is defined as, “The apparent force or (real force), equal
and opposite to the centripetal force, drawing a rotating body away from the
center of rotation, caused by the inertia of the body,”
(OR)
Centrifugal force is a real force
that counteracts the centrifugal force and prevents the object from
"flying out," keeping it moving instead with a uniform speed along a
circular path. REFER IMAGE BELOW
 |
| force direction |
Note that while centripetal force is an actual force, centrifugal force is defined as an apparent force. In other words, when twirling a mass on a string, the string exerts an inward centripetal force on the mass, while the mass appears to exert an outward force on the string.
Centrifugal Force Direction
The tendency of an object following a curved path to fly away from the center of curvature.Might be described as a “lack of centripetal force.” The force that keeps an object moving with a uniform speed along a circular path.
It is not a real force centrifugal force is the inertia of motion.
Formula- Fc = mv2/r
Defined by ChistiaanHygens in 1659
Centripetal Force Direction
Along the radius of the circle, from the center towards the object. Along the radius of the circle, form the object towards the center.
Centripetal force is a real force that keeps
the object from "flying out".
Formula Fc = mv2/r
Defined by Isaac Newton in 1684
CENTRIFUGAL
FORCE (OR) CENTRIFUGE SEPARATION
Centrifuges can be either purifiers
or clarifiers
Gas Oil Cannot Be Separated from
Lubricating Oil, Nor Salt Cannot Be Removed from Sea Water by Centrifugal
Force, because they dissolved together.
Water Can Be Separated from Oil
Because Water and Oil Do Not dissolve together to Form a True Solution When
They Are Mixed. Furthermore, There Must Be A Difference In The Specific
Gravities Of The Materials Before They Can Be Separated By Centrifugal Force.
Centrifugal force is produced through
rotation around an axis. The force generated through the rotation acts in an
outward direction. Depending on the speed of the rotating body, it increases or
drops on the circular path.
PURPOSE OF SEPARATION
Heavy fuel
oil, diesel oil, and lubricating oil, each of these oils have their separate
systems and need to be cleaned before they are used for various purposes. For
example, lube oil is used for cylinder lubrication, while diesel oil is used for diesel marine engines. Centrifuge separation oil cleaning is the best option available on
ships to clean large quantities of oil in an economical manner.
SEPARATION PROCESS
Different methods of separation
- CENTRIFUGE SEPARATION
- GRAVITY SEPARATION
Gravity separation is the emulsion separation. The density differences allow water to separate by gravity. With enough time in a non-turbulent state, the differing specific gravities will naturally separate. The gravitational method is to keep the oil in the settling tank and then drain it continuously. it occurs in a settling tank, over a gradual period solids such as sludge, dirt, etc., will settle out at the bottom of the tank. The heavy liquids, such as water, will settle out above the solids and the lighter liquids, such as oil, will be at the top of the tank. The application of heat will speed up the separation process.
Separation occurs due to the specific gravities or densities of the liquids and solids.
Mechanical separation technology
makes use of this property when light, heavy, or substances of different densities
have to be separated from each other.
- Oil is less dense than water
- Water is less dense than sludge
Why centrifuge separation instead of other separation Method
Have you ever thought about why centrifugal purifiers are operated at very high rpm, while the settling tank needs to be in a steady state for better separation of water and sludge?
But one thing observed is that
during rough weather the settling tank sludge mixes back which was separated
out earlier, which means the movement of sludge makes more scope for separation, it the tendency to move which makes the solids and other heavier particles separate out from the dirty oil mixture more and more easier.
Centrifugal Purifiers
.png)
If the gravitational force is increased,
by using centrifugal force, the separation effect is much greater. This is
shown in the figure by imagining a settling tank on its side and rotated, which
is the basic principle of centrifugal purifiers.
The centrifugal purifiers or separator consists of a bowl containing a set of discs stacked one on top of the other. The dirty oil flows down the distributor and up through the holes in the discs.
Purifier
The centrifuge includes parts that
rotate at high speed. This means that:
•Kinetic energy is high
•Great forces are generated
•Stopping time is long
The Marine high-speed centrifugal separator is specifically designed for cleaning lubricating oils and low viscosity fuel oils from water and solid particles (sludge). The cleaned oil is discharged continuously, while the sludge is discharged at intervals.
The separator handles the following types of lubricating oils and low viscosity fuel oils:
•Distillate, viscosity 1,5 - 5,5
CST/40 °C
•Marine diesel oil, viscosity 13
CST/40 °C
•Intermediate fuel oil and heavy
fuel oil (viscosity 30-380 CST/50 °C)
•Lubricating oil of R & O type,
detergent, or steam turbine.
Needs to update more please write us at marinersight@gmail.com