Re-refiners and processors are facilities that blend or remove impurities from used oil so that it can be burned for energy recovery or reused. Included in this category are re-refiners who process used oil so that it can be reused in a new product such as a lubricant. The most common method of recycling is reprocessing. Industrial techniques such as addition of heat and/or chemicals, the evaporation of water content, filtration, sedimentation, centrifuge separation, and vacuum distillation can be applied to used oil to prepare it for blending with virgin oil for use as industrial grade fuel oil. A large portion of used oil in Utah is processed into #2 diesel fuel blend stock. Only small quantities of used oil generated in Utah are re-refined back into base oil lube stock to make new lubricating oil. Used oil, when re-refined, can be recycled over and over again without losing its lubricating quality.
Standards for the Management of Used Oil (R315-15) applies to used oil processors and re-refiners. The most stringent standards apply to used oil processors and re-refiners because they handle the largest quantities of used oil.