BEFORE READING THIS FIRST CHECK MY BLOG ,OVERHAULING OF PURIFIER ONBOARD SHIP
The separator comprises a frame consisting of the frame lower part, the intermediate part and the frame top part with a frame hood.
The separator bowl (C) is driven by an electric motor (A) via a flat-belt power transmission (D) and bowl spindle (B). The motor drive is equipped with a friction coupling to prevent overload.
The bowl is of disc type and hydraulically operated at sludge discharges. The hollow bowl spindle (B) features an impeller which pumps closing water from a built-in tank to the operating system for sludge discharge.
Outline of function
In fuel oil purifier the untreated fuel contains a mixture of oil solids and water which the centrifuge separates into three layers .while in Operation A quantity of oil remain the bowl to form a complete seal around the underside of the top disc and because of the density difference confines the oil within the outside diameter of the top disc . As Marine fuel oil normally contain the small quantity of water it is necessary to prime the bowl each time that it is run otherwise all the oil will pass over the water outlet side to waste . The water outlet is at greater radius than that of fuel. within the water outlet there is gravity it is which control the radial position of fuel water interface.
Efficiency is increased by the in collection of a number of discs upto 150 that increases the surface area and thus help separation. Disc are separated at a distance of 0.5 to 0.6 millimetre. after passing down the central passage untreated oil is carried by centrifugal force towards the Periphery of the bowl and then passes through the disk stack here is where the actual separation take place in the channel formed between two disc. two forces act on it solid or liquid particle. the particle is pushed upward with the oil stream towards center while the centrifugal force direct it to the Periphery. the residual force on densor particle impurities will drive them towards the Periphery while the less dense oil will be directed towards the centre of the bowl and raised to the outlet connection.
The separation process takes place in the rotating bowl. Un separated oil is fed into the bowl through the inlet (201). The oil is cleaned in the bowl and leaves the separator through the outlet (220) via a paring chamber.
Impurities heavier than the oil are collected in the sludge space at the bowl periphery and removed automatically at regular intervals.
The upper space between the bowl hood and the top disc forms the water paring chamber and contains the paring tube, which pumps the separated water out of the bowl. The oil paring chamber, with its paring disc, is located inside the top of the distributor. From here the cleaned oil is pumped out of the bowl.
The sludge space is in the bowl periphery. There is two slide one is discharge slide or sliding bowl bottom which is present at the top of the bowl body and thr other is operating slide which is fixed below the bowl body. When closing or opening water is given any one of the slide is drained . If opening water is given than discharge slide or sliding bowl bottom drains and operating slide water fills and vice versa for closing water.
The bowl is kept closed by the discharge slide, which seals against a seal ring in the bowl hood.
At fixed intervals, decided by the operator, the discharge slide drops down to empty the bowl of sludge.
The sludge discharge mechanism, which controls the movement of the discharge slide, is comprised of an operating slide and an operating water device. Passive parts are: nozzle and valve plugs. The operating water cover, beneath the bowl, supplies operating water to the discharge mechanism via the operating water ring.
There are no contacting surfaces between process rotating parts (the bowl) and stationary parts (inlet, outlet, feed devices), and the interfacing surfaces are not sealed. As the separation process is carefully balanced regarding pressures and fluid levels, any leakages will not occur as long as the correct running conditions are maintained.
Liquid flow
Separation takes place in the separator bowl to which unseparated oil is fed through the inlet pipe (201). The oil is led by the distributor (T) towards the periphery of the bowl.
When the unseparated oil reaches the slots of the distributor, it will rise through the channels formed by the disc stack (G) where it is evenly distributed into the disc stack.
The oil is continuously separated from water and sludge as it will flow towards the center of the bowl. When the cleaned oil leaves the disc stack it rises upwards and enters the paring chamber. From there it is pumped by the paring disc (F) and leaves the bowl through the outlet (220).
Separated sludge and water move towards the bowl periphery. In purification separated water rises along the outside of the disc stack, passes from the top disc channels over the edge of the gravity disc (K) and leaves the bowl into the common sludge and water outlet (221) of the separator.
Heavier impurities are collected in the sludge space (H) outside the disc stack and are discharged at intervals through the sludge ports(L).
Starting the purifier:
Water seal in purification or sealing water
To prevent the oil from passing the outer edge of the top disc (I) and escaping through the water outlet (221), a water seal must be provided in the bowl. This is done by filling the bowl with water through the water inlet (206), before unseparated oil is supplied. When oil feed is turned on the oil will force the water towards the bowl periphery and an interface (X) is formed between the water and the oil. The position of the interface is determined by the size of gravity disc (K).
Displacement of oil
To avoid oil losses at sludge discharge, displacement water is fed to the bowl.
Prior to a discharge the oil feed is stopped and displacement water added through the water inlet (206). This water changes the balance in the bowl and the interface (X) moves inwards to a new position (Y), increasing the water volume in the sludge space. When the sludge discharge takes place sludge and water alone are discharged.
Sludge discharge occurs while the displacement water is still flowing. A new water seal will therefore establish immediately afterwards. The oil feed is then turned on again.
Gravity disc
In the purification mode, the position of the interface (X) can be adjusted by replacing the gravity disc (K) for one of a larger or smaller size.
A gravity disc of a larger size will move the interface towards the bowl periphery, whereas a disc of a smaller size will place it closer to the bowl centre.
The correct gravity disc is selected from a nomogram, Gravity disc nomogram.The sizes of the gravity discs are normally stamped on the discs.
Clarifier disc
Centrifugal separator used for The Separation of two liquids of different densities fuel and water are known as purifier and those used for separating solid impurities are known as clarifier. purifier will also remove some solid and clarifier will also remove small quantities of water . If the centrifuge is set as a clarify the particulate matter will be a combination of water and solid material if it is set as purifier the free water is continuously discharge therefore the particulate matter will consists of solid materials.
In the clarification mode, the gravity disc is replaced by a clarifier disc which seals off the water outlet. In this case no water seal is required and consequently there is no oil/water interface in the bowl. The clarifier disc is an optional disc with a hole diameter of 40 mm. This disc is not shown in the nomograms.
Sludge discharge function
Sludge is discharged through a number of ports (L) in the bowl wall. Between discharges these ports are covered by the sliding bowl bottom (M), which forms an internal bottom in the separating space of the bowl. The sliding bowl bottom is pressed upwards against a sealing ring (m) by force of the closing water underneath.
The sliding bowl bottom is operated hydraulically by means of operating water supplied to the discharge mechanism from an external freshwater line. Opening water is supplied directly to the operating system in the bowl while closing water is supplied to the built-in closing water tank, and pumped to the operating system through the bowl spindle.
The opening and closing only takes a fraction of a second, therefore the discharge volume is limited to a certain percentage of the bowl volume. This action is achieved by the closing water filling space above the upper distributor ring and pushing the sliding bowl bottom upwards. Simultaneously, the water in the chamber below the operating slide is drained off through the nozzles in the bowl body.
Bowl opening
The key event to start a sludge discharge is the downward movement of the discharge slide. This is accomplished by supply of opening water (372) to the operating slide. Water is drained off through nozzles (Y) in the bowl body. The discharge slide is rapidly pressed downwards by the force from the liquid in the bowl, opening the sludge ports.
Bowl closing
After the sludge is discharged immediately the discharge slide is pressed up and the sludge ports in the bowl wall are closed
The Drive Section
The separator bowl is driven by an electric motor via a belt transmission. The belt pulley on the motor shaft includes a centrifugal clutch.
The Process Section
The separation process takes place inside the rotating separator bowl. The feed and outlet of process liquid takes place in the in and outlet unit on top of the separator frame hood.
Inlet and outlet
The inlet and outlet unit consists of the following parts:
A connection house for pipe connections.
A pipe with a paring disc and a paring tube is located inside the connection house. The pipe has channels for incoming and outgoing process liquid.
The paring disc and paring tube pump the cleaned oil and water respectively out of the bowl.
The paring tube can move radially. During separation it surfs on the liquid surface. It is balanced by a spring.
Under certain operating conditions, the paring tube radial position can be locked in place by two adjustable screws on the connection house.
The paring disc and tube are located inside and at the top of the separator bowl.
The inlet and outlet device is held together against the frame hood by a nut on the end of the inlet pipe.
Height adjusting rings determine the height position of the paring disc and paring tube relative to the bowl.
Separator bowl
The separator bowl, with its sludge discharge mechanism, is built-up as follows:
The bowl body and bowl hood are held together by a lock ring (Centrilock). Inside the bowl are the distributor and the disc stack. The disc stack is kept compressed by the bowl hood. The discharge slide forms a separate bottom in the bowl body.
The upper space between the bowl hood and the top disc forms the water paring chamber and contains the paring tube, which pumps the separated water out of the bowl. The oil paring chamber, with its paring disc, is located inside the top of the distributor. From here the cleaned oil is pumped out of the bowl.
The sludge space is in the bowl periphery. The bowl is kept closed by the discharge slide, which seals against a seal ring in the bowl hood.
At fixed intervals, decided by the operator, the discharge slide drops down to empty the bowl of sludge.
The sludge discharge mechanism, which controls the movement of the discharge slide, is comprised of an operating slide and an operating water device. Passive parts are: nozzle and valve plugs. The operating water cover, beneath the bowl, supplies operating water to the discharge mechanism via the operating water ring.
The separator comprises a frame consisting of the frame lower part, the intermediate part and the frame top part with a frame hood.
The separator bowl (C) is driven by an electric motor (A) via a flat-belt power transmission (D) and bowl spindle (B). The motor drive is equipped with a friction coupling to prevent overload.
The bowl is of disc type and hydraulically operated at sludge discharges. The hollow bowl spindle (B) features an impeller which pumps closing water from a built-in tank to the operating system for sludge discharge.
In fuel oil purifier the untreated fuel contains a mixture of oil solids and water which the centrifuge separates into three layers .while in Operation A quantity of oil remain the bowl to form a complete seal around the underside of the top disc and because of the density difference confines the oil within the outside diameter of the top disc . As Marine fuel oil normally contain the small quantity of water it is necessary to prime the bowl each time that it is run otherwise all the oil will pass over the water outlet side to waste . The water outlet is at greater radius than that of fuel. within the water outlet there is gravity it is which control the radial position of fuel water interface.
Efficiency is increased by the in collection of a number of discs upto 150 that increases the surface area and thus help separation. Disc are separated at a distance of 0.5 to 0.6 millimetre. after passing down the central passage untreated oil is carried by centrifugal force towards the Periphery of the bowl and then passes through the disk stack here is where the actual separation take place in the channel formed between two disc. two forces act on it solid or liquid particle. the particle is pushed upward with the oil stream towards center while the centrifugal force direct it to the Periphery. the residual force on densor particle impurities will drive them towards the Periphery while the less dense oil will be directed towards the centre of the bowl and raised to the outlet connection.
The separation process takes place in the rotating bowl. Un separated oil is fed into the bowl through the inlet (201). The oil is cleaned in the bowl and leaves the separator through the outlet (220) via a paring chamber.
Impurities heavier than the oil are collected in the sludge space at the bowl periphery and removed automatically at regular intervals.
The upper space between the bowl hood and the top disc forms the water paring chamber and contains the paring tube, which pumps the separated water out of the bowl. The oil paring chamber, with its paring disc, is located inside the top of the distributor. From here the cleaned oil is pumped out of the bowl.
The sludge space is in the bowl periphery. There is two slide one is discharge slide or sliding bowl bottom which is present at the top of the bowl body and thr other is operating slide which is fixed below the bowl body. When closing or opening water is given any one of the slide is drained . If opening water is given than discharge slide or sliding bowl bottom drains and operating slide water fills and vice versa for closing water.
The bowl is kept closed by the discharge slide, which seals against a seal ring in the bowl hood.
At fixed intervals, decided by the operator, the discharge slide drops down to empty the bowl of sludge.
The sludge discharge mechanism, which controls the movement of the discharge slide, is comprised of an operating slide and an operating water device. Passive parts are: nozzle and valve plugs. The operating water cover, beneath the bowl, supplies operating water to the discharge mechanism via the operating water ring.
There are no contacting surfaces between process rotating parts (the bowl) and stationary parts (inlet, outlet, feed devices), and the interfacing surfaces are not sealed. As the separation process is carefully balanced regarding pressures and fluid levels, any leakages will not occur as long as the correct running conditions are maintained.
Liquid flow
Separation takes place in the separator bowl to which unseparated oil is fed through the inlet pipe (201). The oil is led by the distributor (T) towards the periphery of the bowl.
When the unseparated oil reaches the slots of the distributor, it will rise through the channels formed by the disc stack (G) where it is evenly distributed into the disc stack.
The oil is continuously separated from water and sludge as it will flow towards the center of the bowl. When the cleaned oil leaves the disc stack it rises upwards and enters the paring chamber. From there it is pumped by the paring disc (F) and leaves the bowl through the outlet (220).
Separated sludge and water move towards the bowl periphery. In purification separated water rises along the outside of the disc stack, passes from the top disc channels over the edge of the gravity disc (K) and leaves the bowl into the common sludge and water outlet (221) of the separator.
Heavier impurities are collected in the sludge space (H) outside the disc stack and are discharged at intervals through the sludge ports(L).
Starting the purifier:
1. Ensure the lines are set and respective walls are open usually the lines are set from settling tank to service tank.
2. Check the oil level in sump.
3. Open operating water valve to purifier and sludging valve to sludge tank
4. Start the purifier feed pump with the three way circulation valve in a position leading to settling tank.
5. Open the steam to the heater slightly ensuring the drains are open so that the condenser drains close the drain once team appears.
6. After temperature is reached click on separator in panel.
7. Check for vibration and wait till RPM reachest 8000 RPM.
8. Open the bowl closing water which closes the bowl.
9. Now displacement water is added. The displacement water will push the oil towards the disc stack. After a calculated time for displacement water addition is stopped.
10. The opening water is given and the seperator discharges.
10. The opening water is given and the seperator discharges.
11. After the discharge,sealing water is added to the seperator bowl till the water comes out of the waste water outlet.
12. Once the water overflows through the waste water outlet stop the sealing water.
13. Now the bowl opening water is given the seperator discharges ,the waste left in system is discharged.
14. Open the three way circulation valve such that the dirty oil feed is fed into the purifier.
15. Wait for the back pressure to built up
16. Check for overflowing of dirty oil through waste water outlet and sludge port
17. Now adjust the back pressure throughout to a value as a specified in the manual.
18. Now purifier is put into operation changed over the clean oil filling valve to service time.
Water seal in purification or sealing water
To prevent the oil from passing the outer edge of the top disc (I) and escaping through the water outlet (221), a water seal must be provided in the bowl. This is done by filling the bowl with water through the water inlet (206), before unseparated oil is supplied. When oil feed is turned on the oil will force the water towards the bowl periphery and an interface (X) is formed between the water and the oil. The position of the interface is determined by the size of gravity disc (K).
Displacement of oil
To avoid oil losses at sludge discharge, displacement water is fed to the bowl.
Prior to a discharge the oil feed is stopped and displacement water added through the water inlet (206). This water changes the balance in the bowl and the interface (X) moves inwards to a new position (Y), increasing the water volume in the sludge space. When the sludge discharge takes place sludge and water alone are discharged.
Sludge discharge occurs while the displacement water is still flowing. A new water seal will therefore establish immediately afterwards. The oil feed is then turned on again.
Gravity disc
In the purification mode, the position of the interface (X) can be adjusted by replacing the gravity disc (K) for one of a larger or smaller size.
A gravity disc of a larger size will move the interface towards the bowl periphery, whereas a disc of a smaller size will place it closer to the bowl centre.
The correct gravity disc is selected from a nomogram, Gravity disc nomogram.The sizes of the gravity discs are normally stamped on the discs.
Clarifier disc
Centrifugal separator used for The Separation of two liquids of different densities fuel and water are known as purifier and those used for separating solid impurities are known as clarifier. purifier will also remove some solid and clarifier will also remove small quantities of water . If the centrifuge is set as a clarify the particulate matter will be a combination of water and solid material if it is set as purifier the free water is continuously discharge therefore the particulate matter will consists of solid materials.
In the clarification mode, the gravity disc is replaced by a clarifier disc which seals off the water outlet. In this case no water seal is required and consequently there is no oil/water interface in the bowl. The clarifier disc is an optional disc with a hole diameter of 40 mm. This disc is not shown in the nomograms.
Sludge discharge function
Sludge is discharged through a number of ports (L) in the bowl wall. Between discharges these ports are covered by the sliding bowl bottom (M), which forms an internal bottom in the separating space of the bowl. The sliding bowl bottom is pressed upwards against a sealing ring (m) by force of the closing water underneath.
The sliding bowl bottom is operated hydraulically by means of operating water supplied to the discharge mechanism from an external freshwater line. Opening water is supplied directly to the operating system in the bowl while closing water is supplied to the built-in closing water tank, and pumped to the operating system through the bowl spindle.
The opening and closing only takes a fraction of a second, therefore the discharge volume is limited to a certain percentage of the bowl volume. This action is achieved by the closing water filling space above the upper distributor ring and pushing the sliding bowl bottom upwards. Simultaneously, the water in the chamber below the operating slide is drained off through the nozzles in the bowl body.
Bowl opening
The key event to start a sludge discharge is the downward movement of the discharge slide. This is accomplished by supply of opening water (372) to the operating slide. Water is drained off through nozzles (Y) in the bowl body. The discharge slide is rapidly pressed downwards by the force from the liquid in the bowl, opening the sludge ports.
Bowl closing
After the sludge is discharged immediately the discharge slide is pressed up and the sludge ports in the bowl wall are closed
The Drive Section
The separator bowl is driven by an electric motor via a belt transmission. The belt pulley on the motor shaft includes a centrifugal clutch.
The Process Section
The separation process takes place inside the rotating separator bowl. The feed and outlet of process liquid takes place in the in and outlet unit on top of the separator frame hood.
Inlet and outlet
The inlet and outlet unit consists of the following parts:
A connection house for pipe connections.
A pipe with a paring disc and a paring tube is located inside the connection house. The pipe has channels for incoming and outgoing process liquid.
The paring disc and paring tube pump the cleaned oil and water respectively out of the bowl.
The paring tube can move radially. During separation it surfs on the liquid surface. It is balanced by a spring.
Under certain operating conditions, the paring tube radial position can be locked in place by two adjustable screws on the connection house.
The paring disc and tube are located inside and at the top of the separator bowl.
The inlet and outlet device is held together against the frame hood by a nut on the end of the inlet pipe.
Height adjusting rings determine the height position of the paring disc and paring tube relative to the bowl.
Separator bowl
The separator bowl, with its sludge discharge mechanism, is built-up as follows:
The bowl body and bowl hood are held together by a lock ring (Centrilock). Inside the bowl are the distributor and the disc stack. The disc stack is kept compressed by the bowl hood. The discharge slide forms a separate bottom in the bowl body.
The upper space between the bowl hood and the top disc forms the water paring chamber and contains the paring tube, which pumps the separated water out of the bowl. The oil paring chamber, with its paring disc, is located inside the top of the distributor. From here the cleaned oil is pumped out of the bowl.
The sludge space is in the bowl periphery. The bowl is kept closed by the discharge slide, which seals against a seal ring in the bowl hood.
At fixed intervals, decided by the operator, the discharge slide drops down to empty the bowl of sludge.
The sludge discharge mechanism, which controls the movement of the discharge slide, is comprised of an operating slide and an operating water device. Passive parts are: nozzle and valve plugs. The operating water cover, beneath the bowl, supplies operating water to the discharge mechanism via the operating water ring.
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