Defining Biodegradable Lubricants
Biodegradable lubricants have been around for thousands of years. Ancient man used olive oil, palm oil, or other plant based oils to lubricate axles, slides, and other moving objects. These oils were not oxidative resistant and required frequent replacement. Whale oil was used for many applications up until the mid-twentieth century due to its excellent lubricity and improved oxidation resistance.
With the discovery and refining of crude oil came an economical lubricant source where additives could be used to extend the lubricant life and performance. Problems started to arise as to how to dispose of the lubricants at the end of their useful life. Many of the early formulations used Lead and other toxic compounds that were harmful to the environment. The mineral oil itself would eventually degrade but not without killing any plants it came into contact with and contaminating water.
In the 1970’s the EPA (Environmental Protection Agency) was established to enforce waste handling laws and clean up contaminated toxic waste sites. A number of laws and regulations have been enacted worldwide to reduce pollution and prevent further contamination of our air and water. In 1999 the U.S. Corps of Army Engineers recommended the use of Environmentally Acceptable Lubricants (EAL) in facilities such as hydropower plants, flood control pumping plants, and lock-and-dam sites.
The Organization of Economic Cooperation and Development (OEDC) , the Coordinating European Council (CEC) in Europe and the American Society for Testing and Material (ASTM) have been working on test methods to determine the biodegradability of lubricants and other materials. Originally these tests methods consisted of exposing a lubricant to bacteria and fungus in a controlled environment for a certain length of time and then determining how much of the lubricant was left. These tests have evolved to include determining what the end result of the biodegradation yields, fish and shrimp kills, effect on vegetation, and bio accumulation.
From these tests it was determined that Food Grade lubricants could not be used as EALs. Even though they are non-toxic in nature, most are made from white mineral oil or PAO (Poly Alpha Olefins) and are not readily biodegradable.
There are a couple of terms you will run into in the field: Readily Biodegradable and Inherently Biodegradable.
To be Readily Biodegradable, 60% to 100% of a lubricant must degrade into non-toxic compounds within 28 days. The non-toxic compounds would include carbon, oxygen, nitrogen, water, and carbon dioxide.
An Inherently Biodegradable lubricant degrades only 20% to 60% into non-toxic compounds after 28 days. The remaining material may take months or even years to completely degrade. There are many compounds that are inherently degradable and not acceptable to be used as an EAL.
Any product that degrades less than 20% in 28 days is considered non-degradable.
Other terms you may see are:
- Bio-Based; these products are made from agricultural sources and depending upon how they are manufactured and the ingredients used they may or may not be readily biodegradable.
- Bio-Friendly: these products are usually non-toxic and may or may not be biodegradable, food grade lubricants would fall into this category;
- Vessel General Permit Lubricants: these lubricants have to meet very strict and expensive criteria and are used at ship-water interfaces;
- Eco-Label: These lubricants must pass a variety of toxicity tests and have requirements for content along with passing two different biodegradability tests.
SWEPCO 737 is readily biodegradable, meets the Cat BF-2 Specification, and meets the Eco-label requirements. It is non-toxic and safe to use in environmentally sensitive areas. It is not H-1 food grade but will meet the H-2 requirements.
As always please contact your sales manager if you have any questions: firstname.lastname@example.org.
Southwestern Petroleum Corporation®