First of all, I would like you to read the answer of a question below;
Question: "Our organization has been offered the opportunity to purchase re-refined oil at a significant discount. Can you explain the re-refining process and whether re-refined oil is as good as virgin base oil?"
Answer: Link; http://www.machinerylubrication.com/Read/29239/understanding-re-refining-process
These impurities contain: unsaturates, polar, asphalt-like, acidic compounds, aldehydes, phenolic compounds, alcohols, non-stable products of hydrocarbons poly-condensation (gums, poly-nuclear aromatics, etc.). Besides, it absorbs NOx and the acidic fuel combustion exhaust gas. These compounds besides dust, fuel, lubricating oil additives degradation products, fuel additives and soot gradually reduce the lubricating oil quality. Moreover, the metallic scrapings act as catalysts at the high combustion temperature and oxygen vicinity, and produce an asphalt-like sludge which increases the viscosity.
The used oil drained from electrical transformers contains a very dangerous material called PCB (polychlorinated biphenyl). This material is toxic by inhalation, potable water or skin adsorption, so that its allowable limit is 2 ppm (mg/kg). This compound is degraded at 300-400oC and produces a compound called dioxine, which is very toxic and very dangerous. Therefore, burying used oilscontaining PCB, or using it in road pavements are not good ways for its disposal. Many decades ago, used oil was burnt, but now this way is not acceptable, because of emitting a lot of pollutants, specially heavy metals ash.
This not only improves its quality to a great extent, but also decreases its evaporation (loss) in engines; specially for multi – grade lube oils.
Some of the Many Users of Rerefined
Thousands of different cars, trucks, and fleets around the world use rerefined oil. A few users include Coca-Cola, United Parcel Service, California Highway Patrol, Southern California Gas, County of Los Angeles, City of Sacramento, Waste Management, the U.S. Postal Service, Frito-Lay, Caltrans, City of San Francisco, and Ventura County, including all emergency vehicles. Rerefined oil is even used on the NASCAR race circuit.
Question: "Our organization has been offered the opportunity to purchase re-refined oil at a significant discount. Can you explain the re-refining process and whether re-refined oil is as good as virgin base oil?"
Answer: Link; http://www.machinerylubrication.com/Read/29239/understanding-re-refining-process
Project References:
Initial meetings and discussions with R&D Professionals of Lube Industry.- Dr. Ashraf Kamal (Researcher in Rerefinement)Asst. Prof. Department of Applied Chemistry & Chemical Technology, (University of Karachi)
- Dr. A.Quddus (Ph.D Petroleum and Petrochemicals)Asst. Prof. NED University of Engineering & Technology
- M.Faisal SiddiquiExecutive Director FRR (Pvt) Ltd. (Keap Technologist)
- Syed Umer AliPlant Manager Mobil Askari Lubricants (MAL Pakistan)
- Mr. Masood AliProduction Manager Orient Lubricants
- M.Bilal KhanManager FRR (Pvt) Ltd. (Keap Technologist)
- Pak Hi Oil Professionals
Tahir Yousuf, Faisal Somro, Masood ali.
Project Parameters & Feasibility:
- RM Collection Surveys (Local venders, Petrol Pumps, Industries)
- Shell Oil is widely used in Pakistan, We can have a contract of purchasing used lube oil from all collection points/ Oil Change service of Shell pumps, Initially I visited more than 50 Petrol Pumps of PSO, Total, Shell, Caltex etc, the Oil collection ratio at Shell Oil Change Service as compared to others is much higher. Also Diesel Engine Used Oil is found in more better condition than Petrol Engine Used Oil.
- Availability of Raw Material (Used Lube Oil Collection/Oil Change Points)
- Requirement = 40 ton/day
- Plant Design (Available Capacities 5-100 ton/day)
- Process Design (Keap Technology (latest): Solvent Centrifuging, Simple Distillation, Column Filtration, 2nd simple distillation)
- Site Inspection (Not done yet)
- Material Balance (as per day production requirements)
- Energy Balance (10% recovered Gas Oil used)
- Govt. Licence (Not Restricted, Already existing business in market)
- Environmental Concerns (Rerefining is prefered and more authenticated than Disposal/Discarding, Oil re-refining reduces greenhouse gases and heavy metal emissions when compared to burning used oil as fuel. Re-refining is a better way to manage used oil. It is easier on the environment and transforms oil into a renewable resource.)
- Cost Estimation (Plant Cost varies between 2-2.7 million $, Depending upon Plant Capacity)
- Plant Fabrication, Process Desgn, Plant Desgn, Complete Installation, Engineering and Procurement Services are offered by "FRR Private Limited" (They have the licence of KEAP TECHNOLOGY, They are already running a Rerefining Plant of 10 ton/day capacity with same technology)
- Manpower (Easily Available)
- RM Collection, Marketing and Complete Plant Fabrication are parallel processes (which may takr 3-6 months, not more than 6 months)
Theoretical Background
During normal use, impurities such as dirt, very fine metallic scrapings due to engine erosion, water or chemicals, etc., can get mixed in with the oil. Also, due to oxidation or thermal degradation, a lot of impurities are generated in lubricating oil, during its application in internal combustion engines.These impurities contain: unsaturates, polar, asphalt-like, acidic compounds, aldehydes, phenolic compounds, alcohols, non-stable products of hydrocarbons poly-condensation (gums, poly-nuclear aromatics, etc.). Besides, it absorbs NOx and the acidic fuel combustion exhaust gas. These compounds besides dust, fuel, lubricating oil additives degradation products, fuel additives and soot gradually reduce the lubricating oil quality. Moreover, the metallic scrapings act as catalysts at the high combustion temperature and oxygen vicinity, and produce an asphalt-like sludge which increases the viscosity.
The used oil drained from electrical transformers contains a very dangerous material called PCB (polychlorinated biphenyl). This material is toxic by inhalation, potable water or skin adsorption, so that its allowable limit is 2 ppm (mg/kg). This compound is degraded at 300-400oC and produces a compound called dioxine, which is very toxic and very dangerous. Therefore, burying used oilscontaining PCB, or using it in road pavements are not good ways for its disposal. Many decades ago, used oil was burnt, but now this way is not acceptable, because of emitting a lot of pollutants, specially heavy metals ash.
Considering the above points, the importance of the used oil re-refining processes for environmental preservation is approved. At least 600 tons of lubricating base oil can be recovered from each 1000 tons of used oil, whereas 6000 tons of crude oil is required to produce this amount of lubricating base oil. The importance of used oil re-refining is such that the U.S. government prepared a set of tax regulations many years ago which resulted in the minimum tax for a mixture of 25% rerefined oil and 75 % virgin base oil.
The re-refined base oil properties are comparable with those of the virgin base oil (directly produced from crude oil), as long as the re-refinement is done properly. Used oil re-refining is not a new process, but some of its applied old versions produce pollutants which are not less environmentally harmful than the used oil itself.
Generally speaking, there are 3 categories for waste oil disposal:
1- Reuse , including re-refining
2- Thermal cracking
3- Incineration / Use as a fuel[1]
The first one , is the best one and is the subject of this study . The second one – although produces acceptable (cracked) products , but is not as good as re-refining. The third one produces a lot of ash, which contains heavy metals and pollutes the environment.
In Europe, three groups of technologies can be considered as representatives of existing regeneration methods:
A) Vacuum distillation plus clay treatment
B) Vacuum distillation plus chemical treatment
C) Hydrogen pre-treatment plus vacuum distillation
At this time, the most common two technologies for used oil re-refining are: Sulfuric Acid plus Bleaching Earth and the Propane Extraction plus Sulfuric Acid plus Bleaching Earth. Both processes generate significant amounts of residues, such as sludge from sedimentation, acid tars, filter cake from bleaching earth and wastewaters, which contained high concentration heavy metals or sulfuric acid (in the range of 17 % w/w). In the first method, some references imply about 200 tons of environmentally harmful by-products generation, versus each 1000 tons of used oil processed. Acid tars were burned in rotary kilns or other furnaces.
Therefore, some modern processes should substitute them. One of the best ones is hydrotreating. The method used by our team, consists of the following steps:
1- Heating the used oil up, to separate water and light compounds
2- Vacuum distillation for the separation of gas oil, base oil and the distillation residue
3- Passing the base oil through a guard bed, to eliminate the catalyst bed plugging constituents
4- Hydro-treating of the obtained base oil
The last step aims at removing or reducing organic acids, chlorine, sulfur or nitrogen, metals (and metalloids) compounds under severe hydro-treating conditions. Also, a lot of the aromatics and other unsaturates (which were not eliminated by previous steps) are saturated to an acceptable low level.
This not only improves its quality to a great extent, but also decreases its evaporation (loss) in engines; specially for multi – grade lube oils.
The lube oil hydro-treating chemistry is different from those of light and middle petroleum cuts.The main target of virgin base oil hydro-treatment (before being used) is controlling its color stability.
Therefore, polar (oxygen-containing, unsaturated, etc.) compounds which produce the brown color in lube oil and also make this color unstable, are eliminated by low temperature – low intensity hydrogenation. Under more severe conditions (higher pressures and temperatures); nitrogen and sulfur are eliminated (as NH3 and H2S) and aromatics are saturated.
This process has many advantages: Production of a high Viscosity Index lube oil with a good and stable color and well oxidation resistance; yet having low or no discards. At the same time, it consumes bad quality feed.
Another important aspect of this method is that all of its hydrocarbon products have good applications. In other words, the product recovery is high with no (or very low) disposals. Other hydrocarbon products are:
Light –cuts can be used as fuel in the plant itself. Gas oil may be consumed after being mixed with heating gas oil. The distillation residue can be blended with bitumen and consumed as the paving asphalt, because it upgrades a lot its rheologic properties. Also, it can be used as a concentrated anti-corrosion liquid coating, for vehicles frames. Moreover, it has some applications in metal smelting industries.
Re refining by Vaccume Distillation and Hydro Fininshing
Step 1: Vacuum Distillation
- Used oil arrives.
- Rejection of inappropriate feedstocks.
- Chemical pretreatment.
- Dehydration (water as steam is cooled and discharged to municipal sewage treatment).
- Vacuum distillation. Asphalt flux is stripped off the bottom and sold for roofing materials. Gasoil is recovered as refinery fuel.
- Lube oil distillates result.
Step 2: Hydrofinishing
- Hydrotreating reactor
- Hydrotreating reactor
- Hydrotreating reactor
- Fractionation results in 100-neutral base oil and 300-neutral base oil.
- Transport to blender to make into finished lubricants.
Advantages of Keap Technology:
Since many other methods are widely used for Re refining but the main advantages of this latest KEAP Technology over all other methods are summerized below after going through the process studies.
- Latest and advance technology
- Percent purity and yield is more than 95%
- Continuous process involved (Not Batch or Semi Continuous)
- Highly Cost effective (Cheapest available method in respect of Capital)
- 10% recovery of Gas Oil which can be used as a fuel for energy requirements
- Environmental Friemndly processes involved
- No conventional/banned process involved like Caustics Soda or Acid Clay method, also it is much better than Molecular distilation technology (Molecular distillation has been declared as a failed technology in Pak Hi Oils and various other Lube companies)
- Video Link: http://www.dailymotion.com/video/xz0t23_keap-technology_auto?search_algo=2#.UXVu6dI6JPI
- Collected Oil is mostly a homogenous mixture of different grades, we can modify the distillation involved in Keap Technology by means of controlling Reflux Ratios in order to distillate Cuts/Fractions of mixed oil.
Re refining is Environment friendly:
Rerefining is prefered and more authenticated than Disposal/Discarding, Oil re-refining reduces greenhouse gases and heavy metal emissions when compared to burning used oil as fuel. Re-refining is a better way to manage used oil. It is easier on the environment and transforms oil into a renewable resource.
Some of the Many Users of Rerefined
Thousands of different cars, trucks, and fleets around the world use rerefined oil. A few users include Coca-Cola, United Parcel Service, California Highway Patrol, Southern California Gas, County of Los Angeles, City of Sacramento, Waste Management, the U.S. Postal Service, Frito-Lay, Caltrans, City of San Francisco, and Ventura County, including all emergency vehicles. Rerefined oil is even used on the NASCAR race circuit.
Why Use Rerefined Oil?
Rerefined oil--an exciting renewable resource--is designed to reduce the environmental impact of used oils by conserving valuable oil resources. Rerefining oil is an energy-efficient and environmentally beneficial method of managing used oil. Less energy is required to recover a gallon of rerefined base stock than a base stock from crude oil. Rerefined oil takes about one-third the energy of refining crude oil to lubricant quality. Rather than using the oil once, rerefining extends the life of a nonrenewable resource by converting it into a usable material that can be recovered and used again.
Re refining Authentication Evidence: http://www.calrecycle.ca.gov/usedoil/rerefined/Distributors.htm
THE RE-REFINING OF
USED LUBRICATING OILS
The lubricating oils used by vehicle engines have to be
replaced at least every 20 000 km.
This oil used to be dumped, but now most of it is re-refined
and reused. This is done in a three step
process, in which water, solids, lighter oils, dissolved metals, degraded
additives etc. are removed.
Step 1 - Dehydration
The oil is boiled in a closed container to remove the water
that has been mixed into it.
Step 2 - Diesel
stripping
The dehydrated oil is then fed continuously into a vacuum
distillation plant for fractionation. Lighter oils boil off first and are
removed, followed by the lubricating oil itself. Other heavier components do
not boil in the conditions used.
Step 3 - Lube oil
distillation and condensation
A liquid extraction process then removes any aromatic
components from the oil.
By this stage, the oil is identical to refined virgin oil. It
is then tested, appropriate additives are added and the oil is ready to be
reused.
INTRODUCTION
Re-refined lubricants have been produced in New Zealand for
over 50 years. However, their acceptance as a high quality lubricant has been a
gradual process, largely because of the scepticism of the public that the
product can be re-refined to its original condition. In New Zealand Dominion
Oil re-refines about 7 million liters per year, while an older acid clay method
is used at Turua near Thames to treat 0.5 - 1 million liters per year.
Most of the sceptics regard the process as some sort of
simple filtration. In fact, the re-refining process used at Dominion Oil is a
highly sophisticated operation using the most modern plant available in the
world today.
The process used is in many ways similar to that used to refine
crude petroleum. Consideration of the composition and refining of crude will give
a better understanding of the re-refining process and highlight the
similarities.
OIL CHEMISTRY
Petroleum products are essentially composed of hydrocarbons,
i.e. compounds containing exclusively carbon and hydrogen. The simplest
hydrocarbon molecule is methane, CH4.
This basic molecule is the main constituent of natural gas.
It can be extended with the addition of more carbon and hydrogen atoms, usually
forming into longer chains. Four carbon atoms in a chain forms butane, one of
the main constituents of LPG. The atoms may also form side chains off the main
chain, or form into ring structures such as the benzene ring. Lubricating oils
are just extensions of these basic hydrocarbon structures, containing from 20
to 70 carbon atoms per molecule, often in an extremely complex arrangement of straight
chains, side chains and five and six membered ring structures.
The lubricating oil
molecules can be divided into three broad groupings:
1.
Paraffinic:
Predominantly straight chains, tend to be
waxy, have a high pour point and good viscosity/temperature stability.
2.
Naphthenic:
Straight chains with a high proportion of five
and to a lesser extent six membered ring structures. Tend to have a low pour
point. For this reason they are used as refrigeration oils. They are highly
carcinogenic and are little used in engine oil. Dominion Oil treats used refrigerator
oils separately from the main plant. As refrigerator oils do not come in
contact with products of combustion they are much cleaner than engine oils.
3. Aromatic:
Straight chains with six membered ring
benzene structures.
In practice, no sharp distinction exists
between these various groupings as many lubricating oil molecules are a
combination, to varying degrees, of the different types of hydrocarbons.
The main point to bear in mind is that these
molecules are extremely stable. Lubricating oil molecules never wear out - all
that happens is that the additives in the oil wear out or deplete and need
replacing.
THE COMPOSITION OF
CRUDE PETROLEUM
Crude petroleum is formed by the bacterial decomposition of
plant and animal remains deposited around 100 million years ago. When pumped from
the ground it can be black, brown or colorless, and is often a mixture of
solids, liquids and gases. The Taranaki fields, for example, are predominantly
gaseous, and are the source of New Zealand's supplies of CNG and LPG. Taranaki
crude contains no lube oil.
The composition of crudes from different sources varies
tremendously, but a typical make-up is as follows:
1.
Gases 5%
2.
Gasoline 35%
3.
Kerosene 10%
4.
Diesel 20%
5.
Lube oil 2%
6.
Tar, Bitumen 28%
THE REFINING OF CRUDE
PETROLEUM
Crude petroleum is initially refined by a process known as
fractional distillation. This process basically consists of progressively
heating the crude to drive off the various fractions as vapors. Some of the
crude is already in gaseous form, but as it is further heated the most volatile
fractions (i.e. gasoline) will begin to boil off. As further heat is applied
the kerosene will begin to distill off.
The lubricating oil fraction is very stable and in-volatile.
To heat the lubricating oil to the temperature required for distillation will
actually decompose the oil, so the diesel and lube oil fractionation is carried
out under vacuum to reduce the effective boiling point of these products. Oil which
will normally boil at 500 oC will boil at 300 oC under the very high vacuum
used.
Boiling ranges are as follows:
Gasoline 40 – 190
oC
Kerosine 190 –
260 oC
Diesel 260 – 330 oC
Lube oil 330 –
400 oC under vacuum
The very heavy components of the crude (i.e. tars) will not
distill even under a vacuum and remain as bottoms or residue.
The lubricating oil fraction must then be further refined
before being suitable for use. The oil is de-waxed by cooling; asphalts,
aromatics and resins are removed by solvent extraction and colored molecules
are removed by hydro treating, or treatment with activated earths. The base oil
molecular type (i.e. paraffinic, naphthenic) must then be blended to provide
the desired properties of color, oxidation stability, viscosity characteristics
and additive response. Only then can the additives be blended into the base
oils to produce the high quality lubricants available today.
USED OIL AND ITS COMPOSITION
Lubricating oil becomes unfit for further use for two main
reasons: accumulation of contaminants in the oil and chemical changes in the
oil. The main contaminants are listed below.
Combustion products
|
|
Water.
|
Fuel burns to CO2 and H2O. For every liter of fuel burnt, a liter of water
is created. This normally passes out through the exhaust when the engine is
hot, but when cold it can run down and collect in the oil. This leads to
sludge formation and rust.
|
Soot and carbon.
|
These make the oil go black. They form as the result of incomplete combustion,
especially during warm-up with a rich mixture.
|
Lead.
|
Tetraethyl lead, which used to be used as an anti-knock agent in
petrol, passes into the oil. Typical used engine oil may have contained up to
2% lead, but today any lead comes from bearing wear and is likely to be in
the 2 - 12 ppm range.
|
Fuel.
|
Unburnt gasoline or diesel can pass into the lubricant, again
especially during start-up.
|
Abrasives
|
|
Road dust.
|
This passes into the engine through the air-cleaner. Composed of small
particles of silicates.
|
Wear metals.
|
Iron, copper and aluminium released due to normal engine wear.
|
Chemical products
|
|
Oxidation products.
|
Some of the oil molecules, at elevated temperatures, will oxidize to form
complex and corrosive organic acids.
|
Depleted additive remnants.
THE RE-REFINING OF
USED OIL
The re-refiner's job is to remove all the aforementioned
contaminants and restore the oil to its original condition. The important point
to note is that the technology used by Dominion Oil is virtually identical to
that used to refine crude petroleum, the difference being that the level of
contamination in used oil is much lower than that in crude oil.
Used oil is uplifted from centralized collection points at
places such as service stations, workshops, recycling depots and factory sites.
The collector is contracted to the Used Oil Monitoring Group, whose members
include BP, Dominion Oil Refining, Caltex, Castrol, Shell, Milburn Cement and
the Department of the Environment. Milburn Cement administers the Group, whilst
the Department of the Environment represents the Government. Milburn Cement
also combust any used oil that cannot be recycled, using it as an alternative
to coal.
The oil is burned at temperatures of approximately 1400 oC,
ensuring complete combustion.
At this temperature dioxins are not formed as they may be at
lower temperatures. This method has been endorsed by the Department of the
Environment as the preferred alternative to re-refining.
Step 1 - Dehydration
The oil is stored to allow water and solids to separate out
from the oil, and then the oil is heated to 120 oC in a closed vessel to boil
off any emulsified water and some of the fuel diluents.
Step 2 - Diesel
stripping
The dehydrated oil is then fed continuously into a vacuum
distillation plant for fractionation in exactly the same fashion as crude
petroleum. The fractions obtained are as follows:
1. Light fuel and diesel. Dominion Oil produces enough
diesel from the used oil feedstock to run all the burners and boilers, giving
total self-sufficiency in fuel.
2. Lubricating oil. The bulk of the feedstock will distill
off in the plant to produce a lubricating oil fraction.
3. Residue. The non-distillable part of the feedstock. This
contains all the carbon, wear metals, degraded additives and most of the lead
and oxidation products. This residue is successfully used as bitumen extender
for roading.
Step 3 - Lube oil
distillation and condensation
The lubricating oil fractions are then passed
through an extraction tower in the presence of N-methyl pyrolidone (NMP). The
NMP is an aromatic selective solvent which, in addition to removing some color
and odor, is able to extract all unwanted aromatic contaminants present in the
paraffinic lubricating oil fraction, subsequent to fractional distillation.
This is important as polycyclic aromatics are very carcinogenic. This process is
commonly used in virgin oil refineries, but Dominion Oil Refining is the only
manufacturer of re-refined oil to use it.
The oil is then passed through a filter press followed by a
polishing filter to remove particles larger than one micron diameter.
The base oil thus produced is chemically and physically indistinguishable
from virgin base oils.
ADDITIVES AND WHAT
THEY DO
Pure mineral oil has good lubricating properties, but it is
the additives in the oil that give it its characteristics and enhance its
lubricating properties to enable it to meet modern requirements. It is
primarily advances in additive technology that have enabled today's 12 months
or 20 000 km oil change periods. Thirty years ago oil changes were recommended every
500 miles (800 km). However small Japanese diesels cars still need about 5000
km oil chenges. The base oil is now really only a carrying medium for the
additive package.
The base oil produced by Dominion Oil is mainly trucked to
BP in Freemans Bay in Auckland where blending occurs.
Further and more detailed information on this process is to
be found in "Used Oil. a Renewable Resource and an Environmental
Pollutant" by David Layzell,
Article written for the previous edition by J. Buckland
(Epsom Girls' Grammer) and G. Vincent (Dominion Oil Refining Co. Ltd.,
Onehunga). Revised by David Christison (BP, formerly of Dominion Oil), and
further information provided by David Layzell. Summary box by Heather
Wansbrough.
Waste Lube Re-Refining Pilot Plant
Youtube Link:
Keap Technology Video Link:
https://www.facebook.com/photo.php?v=429925950377200
https://www.facebook.com/photo.php?v=429925950377200
Method adopted by
The Largest Re-Refiner of Used Oil in North America.
Used Oil Pick-UpMore than 159 actual million gallons of used oil from auto service centers, fast lubes, car dealerships and factories arrives at our re-refineries each year. Both scheduled and emergency pick up service is available. The trucks deliver the used oil and the recycling process begins.
Analytic Testing To Ensure Quality.Oil from a wide variety of sources may contain chemical or physical contaminants that are hazardous or prevent that oil from being used in the re-refining process. Constant testing ensures that our feed stocks are capable of producing the highest quality end products. Result: premium products and environmentally correct recycling.
Dehydration Removes Unwelcome Water.
Water finds its way into many used oil storage areas, so it’s the first thing we remove, using a process of evaporation. The water is collected, treated to be chemically and biologically safe and then discharged.
Light End Recovery
Lightweight chemicals are extracted for reuse. With the water removed, the used oil goes to tall recovery towers where glycol and light fuels are separated and collected. Byproducts: glycol is eventually reprocessed as a finished automotive grade product.
Fuel Stripping
Heavier fuels are removed for industrial use. The used oil is now subjected to heat and vacuum processes which extract middle weight oils. Byproducts: fuel for industrial heating.
Vacuum Distillation
Heavy materials are reclaimed for multiple uses. The heaviest impurities are removed in a complex series of processes. The used oil is actually vaporized in an extreme vacuum and then condensed. Different materials are then separated from the oil. Byproducts: heavy oil for industrial use, such as asphalt extenders, which are made from the heaviest residual material.
Hydro Treating Removes Final Impurities
The remaining oil is treated with hydrogen to remove sulfur, nitrogen, chlorine, heavy metals and other impurities. This step also corrects any issues with odor, color and corrosion performance. The purified oil is then separated by weight – cleaner than the day it was first refined and ready to return to the marketplace.
With a nationwide fleet of trucks, tankers, rail cars and barges, Safety-Kleen collects used oil from thousands of customers across North America.
The remaining oil is treated with hydrogen to remove sulfur, nitrogen, chlorine, heavy metals and other impurities. This step also corrects any issues with odor, color and corrosion performance. The purified oil is then separated by weight – cleaner than the day it was first refined and ready to return to the marketplace.
With a nationwide fleet of trucks, tankers, rail cars and barges, Safety-Kleen collects used oil from thousands of customers across North America.
