Beijing Wanjia Waste Oil Recycling Company tells you the definition of waste oil: waste oil refers to those oils purified or synthesized from crude oil and polluted by physical or chemical impurities after use. Simply put, gutter oil, as its name implies, is used oil derived from petroleum or synthetic oil. During normal use, impurities such as dust, metal chips, water or chemicals may be mixed into the oil. At this time, the oil can no longer play a good lubricating role. The oil must be replaced with new oil or purified oil. The US Environmental Protection Agency's waste oil management standard includes three contents to judge whether it meets the waste oil index. In order to reach the waste oil index of the US Environmental Protection Agency, the following three criteria must be met:

Source-Waste oil must be extracted from crude oil or made of synthetic substances. Animal and vegetable oils are not included in the definition of waste oil by the US Environmental Protection Agency.

Use-consider whether and how the oil is used. Oils used as lubricating oil, hydraulic oil, heat transfer fluid, buoyancy fluid and other similar purposes are regarded as waste oil. Unused oil, such as waste fuel at the bottom of new fuel storage tanks, does not belong to the waste oil defined by the US Environmental Protection Agency, because these oils have not been used. The definition of waste oil by the US Environmental Protection Agency does not include cleaning products and solvent products, and there are also some petroleum derivatives, such as antifreeze and kerosene.

Contaminants-Whether the oil is contaminated by physical or chemical substances should be considered. In other words, according to the definition of the US Environmental Protection Agency, gutter oil must be polluted. This definition includes residues and pollutants from the operation, storage and treatment of waste oil. Physical pollutants may include metal fragments, sawdust or dust. Chemical pollutants may include solvents, halogens and hydrolyzed salts.