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Facts About Re-refined Motor Oil

What is Re-refined Oil?

Used motor oils can be re-refined to make new lube oils. Re-refining is an efficient and sophisticated process which removes contaminants and impurities producing premium grade base oils. One gallon of used motor oil will yield about 0.7 gallons of re-refined oil. Lube oils can be re-used indefinitely in an endless cycle from refinery to engine to refinery again.

The Chicken and the Egg

A number of years ago oil companies using re-refined oil in their blends were required to print this fact in big red letters on their containers. Many consumers interpreted this labeling as a visual stop sign to the purchase of those oils. They did not want to buy "dirty" used oil. Oil companies are no longer required to report to the consumer the use of re-refined base oils and, in fact, some companies currently do put re-refined oils into their products without any indication on the label.

Ideally, all used motor oil should be re-refined and put back into the system by all oil companies without fanfare. Two barriers to this are the cost of certification for new blends of oils and public perceptions about the quality of re-refined oils. Oil companies can not easily add re-refined oil to their blends because it costs a large amount of money to get an API test and certification (quarter of a million for consumer blends, half a million for heavy duty blends.) Many oil companies are reluctant to use and promote re-refined oils because the general public has misconceptions about the quality of these products. Once the public understands that API certified re-refined oils meet the same high quality standards as oils from crude, they will be more receptive to re-refined oils, and oil companies will be more likely to market re-refined products.

As an aside, if a company wishes to promote their product as re-refined there are government requirements regarding the percentages in the blend. To be labeled as a re-refined product, federal standards require oil blends to contain at least 25% re-refined oil. California standards require that the blend contain 75% re-refined oil.

A Look at Oil Refining Efficiencies

The re-refining of used motor oil is a very efficient process. 1.41 gallons of wet used motor oil will yield 1 gallon of re-refined motor oil. (This ratio is supplied by Evergreen Oil Refinery.)

Comparing this to crude oil, it takes 84 gallons of crude to yield 1 gallon of motor oil. (This ratio is supplied by the American Petroleum Industry and is based on 1995 average yields for U.S. refineries.)

But you can not simply compare those ratios and conclude that refining from crude is immensely inefficient. Crude oil refining yields large amounts of fuels. Below is a comparison of refining from used motor oil and refining from crude.

Re-refining one unit of used motor oil will yield:

71% lube oil
5% fuels
14% asphalt
10% water

Exact percentages can vary.
Refining one unit of crude oil will yield:

84% fuels (46% gasoline, 38% other fuels)
9% gases
4% coke
3% asphalt and road oil
3% petrochemical feed-stocks
1% lube oil

The total volume of products made is greater than 100% due to "processing gain"

Why use Re-refined Oil?

Lube oil is a premium substance which can be re-refined and reused time and again. Re-refined oils carrying the API logo meet the same high quality standards as lube oils made from crude. In addition, re-refined oils are comparable in price to virgin oils.

When you buy re-refined motor oil you will be helping to create a market for the product and will be driving the recycling process. Most of the used motor oil taken to oil collection centers is not truly recycled. Out of all the used motor collected 55% is burned as a cheap source of fuel, releasing toxins into the atmosphere. 35% is either dumped, sent to landfills, incinerated, used to oil roads or used in industrial processes. 10% is re-refined (recycled) to make new high quality motor oils.

Who Already Uses Re-refined Oil?

Mercedes Benz puts re-refined oil in every new car manufactured in Germany. The City of Santa Monica has been using re-refined oil in their fleet vehicles for the past 6 years. Increasing numbers of public agencies, private firms and cities are using re-refined oils: United States Postal Service, National Park Service, Coca Cola Bottling Company, Proctor and Gamble, the Cities of Los Angeles, Long Beach, Carmel, Escondido, Oxnard, San Jose, San Francisco, Thousand Oaks and many more.


For more information contact the City of Santa Monica's
Haz Mat Section at (310) 458-8711.



Last updated: Tuesday, 02/15/2011

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