Oil Purifier: The Ultimate FAQ Guide

This guide will take you through all the vital aspects you need to know about oil purifier systems.

From design, specification, parts, working principle to improving efficiency; you will learn everything you need to know in this guide.

So, if you want to be an expert in oil purifier systems, this is the right guide for you.

Let’s dive right in.

Table of contents hide

What is Oil Purification?

This is the process of eliminating solids, gases, or sludge, from oil.

Oil purification is a vital undertaking that helps in the maintenance of machines.

oil purifier

Oil purifier

Where do Contaminants Come from in Oil?

Contaminants originate from several sources such as:

Here are some sources that will contaminate oil:

  • External environmental sources
  • Air vent systems that may let in particles and dirt.
  • Internal environmental sources
  • Oxidation that forms acids, resins, etc.
  • Rust and corrosion
  • Leaking coolers

These contaminants ultimately cause damage to the machinery in question.

What Are Some Contaminants of Oil?

Contaminants get into oil during operation and storage processes.

They include:

  • Moisture
  • Solid particles
  • Gases and fumes
  • Asphalt-resinous paraffin deposits
  • By-products of combustion
  • Acids and varnishes
  • Oil sludge
  • Coolants
  • Soot
  • Metallic particles
  • Minerals and dirt
  • Unsaturated hydrocarbons
  • Metal oxides
  • Poly-aromatic hydrocarbons
  • Additive remnants
  • By-products of oil decomposing
  • Fuel

What are Some Effects of Impure Oil?

These include:

  • A decrease in oil efficiency
  • Corrosion of the moving and mechanical components
  • A reduction in the load-carrying capability
  • Degradation from microbial elements
  • An explosion in the crankcase
  • A high production rate of acid in piston engines
  • High maintenance costs
  • A reduction in machine performance

What are Some Methods of Oil Purification?

There are several methods that you can apply when purifying oil.

They include:

Separation Oil Purification Method

In this process, one purifies oil using special equipment known as separators.

There are two kinds of separators namely open separators and vacuum separators.

This process will separate oil and other floating solids from water.

Thereafter, you can skim it away.

Note that oil is lighter than water so this means it will float on water.

Also, wastewater can come with other kinds of contaminants because of its nature.

These contaminants, particularly tiny droplets, do get hung up.

An oil separation method targets oil relying on the difference in gravitational force between oil and water.

The heavy solid particles will ultimately settle at the bottom and oil will remain on top.

This effect will also leave the wastewater as the middle layer.

After this, you can scrape out the sludge and skim the oil from the top layer.

The wastewater can then undergo further filtration depending on how you plan to use it.

In this technique, wastewater will pass a series of plates on an incline in an oil-water separator.

The plates will assist in the separation of oil, water, and sludge into separate spaces.

Heavy materials like solids and sludge usually drop to the bottom part.

The plates can perform unique functions even though the oil particulates can be tiny in size.

Oil particulates pass tumble over the surface of plates as wastewater pass over these plates.

This effect makes them collect and thereby forming large globules.

These globules will have great buoyancy.

This effect will assist much of the oil to separate and come above the water layer.

Sedimentation Oil Purification Method

This process involves the use of gravity to make the solid particles and water settle at the bottom via gravity.

On the contrary, this method takes a long time to effect.

Filtration Oil Purification Method

In this method, you will partially eliminate the solid particles from oil via a filter medium.

These oil purifiers will employ the usage of both fine and coarse filters.

Centrifugation Oil Purification Method

In this process, you will use the effects of gravity in purifying oil.

One can hasten the centrifugal force in tandem with gravity to enhance the process.

This process is simple to operate.

The first step involves rotating a drum that contains impure oil.

This centrifugal force will send items that have a higher density than the density of oil to the edge of the bowl.

These include free water and other solids.

This centrifuge will have parts that will rotate at high velocities.

This means that the kinetic energy is high, the stopping time is long, and it generates great forces.

Ensure the parts that rotate balance in the best ways.

This balance will lower the chances of extra vibration from occurring.

These vibrations can cause a breakdown during oil purification.

Despite being a fast oil purification method, it does not eliminate moisture.

This process is complex and it has low reliability since you need to constantly monitor the process.

Thermovacuum Oil Purification Method

This process relies on the difference in temperature between the liquids within the system.

When the temperature is low, water will evaporate from oil at room temperature.

Thermovacuum drying will lower the level of water in oil to a rate of 10 ppm.

Also, this process is simple and efficient.

Besides, this method is automatic hence easy to control the entire purification process.

This method is effective at removing water as well as gas from the oil.

However, a high vacuum oil process is slow thus takes a long time to conduct.

Adsorption Purification

This oil purification method does not eliminate gases and solid particles from oil.

However, it is suitable when it comes to removing water, aging products, and sludge.

This process will use materials that have a porous surface.

The porous surface will hold and eliminate moisture and contaminants that are in oil.

Also, the durability of the adsorbent materials is low.

This means you need to dispose of it once you purify the oil.

Besides, the oil purification process happens at a low rate.

These adsorbents can effectively lower the acidity in the oil.

Adsorption purification employs adsorbents that can be natural or artificial.

These include silica gels, zeolites, bleaching clay, synthetic alum inosilicates, etc.

What Factors Will Affect Centrifugation in Oil Purifiers?

Centrifugation is a process that assists in the separation of particles from a solution with their:

  • Size
  • Shape
  • Rotor speed
  • Density
  • Viscosity of medium

Some factors that will affect this type of oil purification method include:

Speed of Rotation

Velocity of the centrifuge rotation depends on the rotation speed of the rotor and the radius of the particle’s rotation.

The relative centrifugal force of the field describes the centrifugal conditions.

The higher the rotation speed, the faster the process of oil purification will be.

Centrifugation Time

The time it takes to conduct centrifugation influences the centrifugation effect.

Centrifugation time depends on the type of material you are dealing with and the centrifugation method.

Differential centrifugation is the time it takes particles to completely settle at the bottom of the centrifuge drum.

Is-density gradient centrifugation is the equilibrium time a particle takes to reach the iso-density point.

The longer the centrifugation time, the more effective the oil purification process.

Difference in Density

The greater the difference in density, the faster the oil purification process.

A powerful centrifugal force will effectively separate particles from oil than when using gravity alone.

Temperature and Viscosity of Oil

A highly viscous oil solution will negatively affect the oil purification process.

This is because oil and the contaminants will offer much resistance to the purification process.

Also, the lower the temperature, the longer it will take to purify the oil.

Other factors include:

  • Gravity disc
  • Oil feed rate/ rate of throughput
  • The outputs back pressure
  • Distance of the particles during displacement

How Does Non-Continuous and Continuous Oil Purifier Compare?

In a non-continuous oil purifier, you will manually clean the sludge after some operating time.

This means you will turn off the oil purifier for the cleaning process to happen.

Also, it takes a long time to purify the oil and is labor-intensive.

Besides, an operator needs to frequently monitor the level of sludge to see if it is time for cleaning to occur.

 continous oil purifier

continuous oil purifier

A continuous oil purifier will automatically clean out sludge at regular intervals.

It is also known as a self-cleaning oil purifier.

The advantage is that you will spend less on labor since it is automatic.

 non continous oil purifier

 non continuous oil purifier

What are Some Safety Measures When Starting and Operating an Oil Purifier?

Oil purifiers need systematic steps when operating.

This will assist in ensuring all is well and the operators are safe.

Here are some safety measures to undertake while starting the equipment:

Check Oil Levels

When the oil is in inadequate amounts, it will lead to less lubrication thus damage gears and other moving parts.

Ensure the oil is at the right level before starting the oil purifier.

Monitor the Brake System

Make sure the brake is in a release position.

When you do not release the brake, the oil purifier will operate at minimal speeds while increasing the motor current.

Besides, this will damage the brakes by causing wear and tear of the brake system.

Open Inlet and Outlet Points

When the discharge valve is not open, the oil purifier will overflow.

This means oil will find its way into the sludge.

When the inlet valve is not open, the purifier will fail to receive an adequate supply of oil.

Clear the Tank Valves

Ensure the tank valves are open.

This ensures the discharge from the oil purifier will pass efficiently to the tanks.

Also, it prevents the build-up of backpressure that may cause the oil purifier to overflow.

Check the Level of Operating Water

The purifier bowl will fail to rise if there is insufficient water in the other separate water tank.

This means the sludge ports will be in an open state.

Monitor the Feed Pump

Ensure the feed pump is operating properly.

Make Sure to Open Heater Valves

Ensure to open oil valves before opening the steam line.

This prevents damages and entry of water into the oil.

Increase the Temperature

One can increase the temperature of the oil to the limit that indicates on digital oil purifier control panels.

Some automatic purifiers have a preset minimum temperature level.

The machine will not start if the oil fails to reach this temperature.

Check for Vibrations

Ensure the equipment produces no abnormal vibrations when you start it.

When you notice abnormal vibrations, shut the equipment down and check before restarting.

Monitor Solenoid Valves

Ensure these valves are operating well by ensuring the lights on them are on.

Repair if not working to ensure an efficient oil purification process.

Also, here are some steps to take to ensure a safe operation of oil purifiers:

  • One should never power the separator till you assemble and tighten all the components.
  • Also, you should not discharge vibrating separators and should always use the emergency button to stop them.
  • Besides, you should not start disassembling the oil purifier before it comes to a complete stop.
  • Always use instructions in the manual book to set the discharge intervals of the oil purifier.
  • Check the cause of alarms and never ignore when an alarm sound goes off.
  • Always use the separators with the right liquid as laid by the manufacturer and not other liquids.
  • Also, use the correct power supply when operating oil purifiers to ensure their efficiency and durability.
  • Use the manual book to supply the correct and right amount of conditioning water before you discharge.
  • Ensure you clean the operating system at regular intervals to avoid malfunctioning of the sludge discharge.
  • Make sure to use fully competent personnel to install, operate, maintain, and conduct emergency procedures.

What is the Process Cycle of an Oil Purifier?

This is how this process goes on:

  • Start by feeding a specific water amount to the separator bowl that will form a water seal.
  • Thereafter, feed impure oil to the center of the separator bowl.
  • Water and sludge will accumulate to the edge of the separator bowl during the separation process.
  • Clean oil will enter the separator by use of integrated paring discs.
  • Excess water and sludge exit the separator bowl via the water or sludge outlets and head into the sludge tank.
  • The oil feed will come to a stop after the set time between the discharge intervals.
  • Thereafter, you will add displacement water into the separator bowl.
  • Displacement water will lower oil loss through the sludge discharge valves.
  • Then you will activate the sludge discharge as the displacement water flows.
  • After this, the next process cycle begins by adding water to form a new water seal.

What are Some Safety Features of An Oil Purifier?

These features will protect the operators and enhance the oil purification process.

They include:

  • Emergency brakes that will regulate the speed.
  • A water transducer that prevents water from mixing with the oil.
  • Low-pressure switches that are in the outlet for the clean oil that prevents oil from leaving the system with water.
  • A high-pressure switch will deter water to come into the clean oil outlet with the clean oil.

How do Oil Purification and Oil Regeneration Compare?

 oil purification

 oil purification

In several instances will people use these words to mean the same thing.

However, they are different as they have specific characteristics.

Oil purification will clean oil from contaminants and you can use it as one system or as part of oil regeneration.

On the other hand, oil regeneration will eliminate aging products with the assistance of adsorbents.

It will also stabilize the oil with the addition of additives.

Besides, oil regeneration can also improve the color of the oil and eliminate contaminants that standard purification cannot.

Oil regeneration will remove carcinogenic products.

Also, oil purification depends on oil filtration, degasification, dehydration, and other procedures.

Typical oil purification processes involve mechanical filtration together with vacuum degassing.

 oil regenerating process

regenerating process

What are Some Factors to Consider During Oil Purification?

They include:

Density of Oil

When you have a low-density material, oil purification will be better.


This pressure is dependent on density, feed viscosity, temperature, etc.

Adjust back pressure to make sure paring discs absorb clean oil as it passes to the clean oil tank.

Throughput of the Oil Feed

This is the quantity of the oil that you pump into the oil purifier per unit of time.

A minimum throughput will optimize the oil purification process.

Revolutions per Minute [rpm]

A high RPM ensures there is an adequate centrifugal force to separate oil from the contaminants.

Temperature of Oil Inlet

The impure oil will fast pass via a heater to raise its temperature.

A feed with a high temperature lowers its viscosity thereby ensuring better oil purification.

Why is Centrifugation a Preferred Method in Oil Purifier?

centrifugation method of oil purification

centrifugation of oil purification

The reasons for this is because:


The cost of installing a centrifugation oil purifier is low.

Also, it will increase the durability of the purifier.


This process requires minimal maintenance.

It will also save you more in terms of operating costs.

Besides, it will also enable you to continue the purification process with minimal downtime.


Centrifugation is capable of eliminating small particles effectively.

This enables you to get the cleanest oil.

Single Operation

There oil purification systems that require you to perform various steps to eliminate certain impurities.

Centrifugation can eliminate both water and solid impurities in one single operation.

This saves you time and money as you do not need to acquire extra equipment for specific tasks.

Also, you will end up using small workspaces due to this capability.

What are the Benefits of Using an Oil Purifier?

They include:


They minimize corrosion, tear, and wear within the fluid systems.


It will extend the life span of oil.

Enhancing Productivity

Besides, it enhances the productivity of oil and equipment.


Some oil purifiers are easy to move from one place to another.


They can purify oil in large amounts thus meeting your purification needs in a timely fashion.


Also, it will lower the time that one needs to change the oil.


It will increase the reliability of the equipment.

Environmental Protection

Also, it will reduce environmental degradation as there is less frequent oil disposal.

What are the Parts of an Oil Purifier?

parts of oil purifier

parts of oil purifier

Several components make up an oil purifier.

These parts work together to ensure the purification process is as effective as it can be.

Ensure these parts are in good working condition for the best purification process.

Besides, operators need to understand how these parts function and look like.

This enables them to troubleshoot problems with ease as they have the necessary know-how.

The parts of an oil purifier include:


This is the main part that holds the entire oil purifier.

It houses all the components that you will find inside the oil purifier.

Cast iron makes up this component

Bowl and Disk

These parts are within the external frame.

They can be solid assemblies that operate non-continuously.

Also, they have ample space to hold the sludge that separates from oil during the purification process.

Besides, they can come in arrangements where the upper and lower components are separate.

These separate components will assist in discharging all the sludge in a continuous operation.

Also, stainless steel makes up these parts as they provide high tension and are durable and easy to clean.

Vertical Shaft

This shaft will convert electrical power into mechanical power.

The mechanical power will provide the rotational force in the bowl at high speeds via the spur gear and horizontal belts.

Alloy steel makes up the vertical shaft.

Gear Pump

This part has a horizontal shaft or a discharge gear pump.

There are systems an external supply pump can be in place of the gear pump.

Belt Drive

This is also known as the horizontal shaft.

An electrical motor will drive the horizontal shaft via clutch pedals.

It will transmit the rotational motion to the bowl assembly.

Some models use unique belts that have an elastic trait to replace the horizontal shafts.

This will eliminate the need to use a gear assembly.

The material of the horizontal shaft is alloying from steel.

Spur Gear

This gear will transmit rotational motion as it is between the horizontal shaft and the vertical shaft.

The material that makes up this component is aluminum bronze.


These are also known as friction pads.

Electric motors will experience an overload if you connect them directly to the bowl assembly.

This is because the entire assembly is heavy.

Clutches or friction pads and the drum assembly will assist in avoiding this as you will install them in the horizontal shaft.

The frequency supply that goes to the motor will influence the number of clutches or friction pads.

Normally, they range between 2 to 4 in number.

The pads within the drums will begin to move gradually as you start the motor.

This is due to the centrifugal force hence causing friction to the internal walls of the drum assembly.

Also, the rotation of the shaft and bowl happens gradually with no overloading or damage to motors and gears.


What are the Types of Centrifuges that an Oil Purifier Has?

There are two types and they depend on the application:


This is when you arrange the centrifuge to separate two liquids that have varying densities.

An example of these liquids is water and oil.

Its main component is gravity discs with the correct size or dam rings.

These parts will assist to create an interface between water and oil.


This is when you arrange the centrifuge to eliminate small amounts of water and impurities.

Also, this system will not use gravity discs since it mostly eliminates solid impurities.

However, it uses a sealing ring that will help to keep impurities intact until you begin to desludge them.

How Does an Oil Purifier Work?

The operation system of an oil purifier is simple.

  • First, ensure all parts are in good working condition.
  • The oil purifier has stacks of the disc that can reach up to 150 and has a small gap separating them.
  • Also, there is a sequence of holes that align to each disc on the outside edge.
  • These holes allow dirty oil to enter the oil purifier.
  • There is a huge difference in gravity and centrifugal force.
  • This makes the heavy particles and impure liquid move on the outside.
  • Clean oil will then flow inwards to undergo the purification process.
  • Sludge and other impurities will discharge in a continuous manner or at set intervals.
  • This depends on the configuration, automation, and system that you are using.
  • Besides, before introducing oil in the system, you will introduce a water seal.
  • This will inhibit oil from flowing out via the heavy liquid outlets.
  • The temperature and the feed rate are vital elements to consider for oil purification.
  • A single-stage purification is enough for normal oil.
  • On the contrary, oil that has a lot of sludge or catalyst mixtures requires several oil purifiers.
  • This means you will use them in a parallel arrangement.
  • To get the best results, you need to arrange them in a series.
  • Also, new and modern oil purifiers will automatically desludge at regular intervals.
  • Discharge detectors will monitor the sludge and sound an alarm when there is an abnormality.
  • After the purification process, clean oil will exit the purifier.

Here is how the centrifugal oil purifier operates:

  • Gears will assist in rotating the centrifuge bowl at high speeds.
  • Impure oil will enter the bowl as it rotates.
  • Heavy impurities will move towards the bottom of the bowl.
  • Fine solid particles that cannot sink will move towards the periphery of the centrifuge bowl.
  • Also, one can apply heat to oil to increase viscosity hence enhance the purification process.
  • The water layer within the bowl will act as a seal.
  • With no seal, oil can flow out with the impurities.
  • Pure oil then leaves the bowl with no impurities.

How Do an Oil Purifier and Oil Clarifier Compare?

Here is how these two compare:

Oil Purifier

An oil purifier will eliminate water and other floating solid materials from the oil.

It comes with two outlets: one for the water and the other for the clean oil.

Besides, the gravity disc is at the top part of the system.

In this system, sealing water is a requirement.

Also, there are blind discs at the top part of the disc stacks.

 oil purifier

oil purifier

Oil Clarifier

It can eliminate both finer and lighter impurities from the oil.

Also, it has a single outlet for clean oil.

Besides, it has no gravity discs but has a sealing ring.

It also has a blind disk at the bottom part.

Besides, sealing water is not necessary for this type of system.

 oil clarifier

 oil clarifier

What Will Cause the Oil Purifier to Experience Excessive Vibration?

Several factors will cause an oil purifier to have more vibration and they include:

  • When the bearing system fails.
  • Also, when there is too much sludge on the inside of the bowl.
  • Uneven wear of the frictional clutch can cause extra vibration.
  • Besides, when the gear gets worn out, it will have this effect on the system.
  • An extremely high or too low motor speed.
  • When there is a foundation damper and the spring fails.

What is an Oil Purifier Overflow?

The reasons include:

  • A failure in the sealing water.
  • The main sealing ring may be worn out.
  • Presence of plenty of sludge within the bowl.
  • Also, when the oil has an extremely low temperature.
  • Failure with the operating water may cause the overflow.
  • The rotation of the bowl has a low revolution per minute [rpm].
  • When there is too much throughput rate.
  • Besides, the incorrect oil purifier disc may cause overflow as the inside diameter would be too large.

 oil purifier overflow

 oil purifier overflow

What will Make an Oil Purifier not Build up Speed During Operation?

These instances are:

  • A failure in the bearing system.
  • When the level of the sump oil is too high.
  • Also, when the motor is running at an overload.
  • Besides, too much sludge in the bowl can cause this effect.
  • Touching with a break is also another cause of the speed not building up.
  • When the horizontal shaft and the vertical shaft are not aligning.
  • In single phasing when there is a power failure.
  • Also, an incorrect touching with the friction clutch due to it wearing out.

What is Steam Jetting When It Comes to Oil Purifiers?

This happens when you blow steam inside the engine oil before you begin its purification.

It will cause coagulation of the colloidal carbon to occur.

This results in the oil purifier eliminating carbon more efficiently and effectively.

Why is it Important to Maintain Backpressure When Using an Oil Purifier?

It is vital to adjust the backpressure and maintain it once you start operating the oil purifier.

Also, it varies the same way the density, pressure, and oil seed inlet vary as well.

Besides, it is responsible for making sure the oil paring discs get inside clean oil as it heads to the oil tank for clean oil.

What is Partial Desludging When It Comes to Oil Purifiers?

Here, the piston that will ensure the closing of the discharge valves for the solids will open partially.

This effect will therefore cause a small portion of the solid impurities in the sludge chamber will leave the system.

However, the sludge residue remains within the drum and prevents liquids from getting into the insides of the drum.

This process allows you to continually feed the impure oil as it is not necessary to stop the operation.

On the contrary, complete desludging happens when you empty the drum.

Here, you will shut off the input of the liquid to prevent the loss of fluid that you are separating.

Also, one can feed liquid that has a great weight than the main liquid before you begin the desludging process.

How will you Dislodge an oil purifier?

This is the process of desludging an oil purifier:

  • Start by opening the sealing water.
  • Wait for some time until the water begins to come out from the overflow line.
  • Proceed by closing the sealing water.
  • Also, close the operating water at this point.
  • After this, open and close the desludging water.

What is a Lube Oil Purifier?

This is a system that assists in the lubrication of moving surfaces and piston rings.

It pumps oil through oil filters, crossheads, guides, pistons, into the engine casings.

Therefore, it helps in the smooth running of machinery by:

  • Minimizing heat
  • Neutralizing by-products from acid combustion
  • Minimizing scuffing
  • Reduction of friction

lube oil purifier

lube oil purifier

How Do You Troubleshoot an Oil Purifier?

  • Slipping belt
  • Worn out gear units
  • Faulty bearings
  • Faulty motors
  • Less frequency
  • Worn out coupling pads

How Should You Maintain the Efficiency of An Oil Purifier?

Maintenance ensures it operates efficiently and for a long period.

Repair all broken and faulty components to ensure proper oil purification.

Replace damaged components with genuine parts.

Clean the equipment regularly to increase longevity.

Conduct regular inspections to ensure all parts are in good working condition.

How Do You Start an Oil Purifier?

Begin by checking the oil level, water level, sealing, and desludging water.

Open oil heater steam until it reaches between 85 and 90 degrees Celsius.

Start the oil purifier and ensure the amperage rises to 20 Amps then come down to 5 Amps.

Open the operating water, then the sealing water, and wait for the water to come out of the outflow line.

Then, close the sealing water.

Thereafter, you will open the pump of the oil purifier and adjust feed rates while monitoring backpressure.

Ensure back pressure is about 0.8 bars

What are the Features of Oil Purifiers?

These features vary and include:

  • A fully automatic operation.
  • Ease of maintenance.
  • An efficiency of 99.5% when it comes to eliminating particles.
  • It can remove water contamination from 10000 ppm to less than 100ppm.

At FilSon Filters, we offer complete solution when it comes to oil purification systems.

From design, replacement to optimizing operations, FilSon Filter offer custom solution for all your oil purifier systems.

Contact us now for all your oil purifier systems.

Scroll to Top