A method is provided for reprocessing a petroleum-based waste oil feedstock into diesel fuel. The method includes forming a treated feedstock by (a) filtering the feedstock, thereby removing solids and metals from the feedstock, and (b) dehydrating the feedstock; vaporizing the treated feedstock to produce an oil vapor; passing the oil vapor through at least one catalyst bed and subsequently through a cooler, thereby converting the oil vapor to a hydrocarbon liquid product with a diesel product boiling point range; and removing contaminants from the hydrocarbon liquid product, wherein the contaminants are selected from the group consisting of particulates and color precursors.

A system for recovering gel-mass from a gel-mass-containing waste material. The system includes mangle rolls, a heated accumulator for receiving and melting the gel-mass-containing waste material to provide an oil phase and a non-oil phase; a pumping system; an optional mixer; and a control system.

Proposed is a process of producing a high-quality lube base oil using a refined oil fraction obtained from waste lubricant as a feedstock. The process includes purifying waste lubricant to obtain a refined oil fraction, pretreating the refined oil fraction, and blending the pretreated refined oil fraction with unconverted oil (UCO), before or after vacuum distillation and catalytic dewaxing of the unconverted oil, or between the vacuum distillation and the catalytic dewaxing of the unconverted oil.

A process for the enhancement of the byproducts of a process for the regeneration of exhaust oils is described, wherein said process for the regeneration of exhaust oils which includes at least one of the following steps: a) passing of the oil to be regenerated into one or more centrifuges, b) storage of the oil, before treatment, in suitable containers, c) desiloxanation and d) filtering. The byproducts of one or more of steps a) to d) are treated, gathered and mixed with one another and added to the bitumen coming out as tail of a fractioned distillation step of the above-said regeneration process of exhaust oils.

A plant for the carrying out of a process according to any one of the preceding claims is also described, comprising a processing unit for each of the byproducts coming from steps a) to d) and a mixer (6) with stirring (7).

In an embodiment is provided a process to re-refine used oil that includes introducing a used oil and a solvent to a separation unit under separation conditions selected to produce a purified oil product, the separation unit comprising a porous membrane, a semiporous membrane, or both; and separating the used oil to obtain an effluent comprising a purified oil product. In another embodiment is provided an apparatus for re-refining used oil that includes a separation unit comprising a porous or semiporous membrane; a used oil feed coupled to an inlet of the separation unit; and an inlet of a diffusate collection unit coupled to an outlet of the separation unit. In another embodiment is provided a composition generated from a membrane separation process that includes a base oil, the composition having a soot content of about 0.05% or less.

The present technology relates to processes for converting PBWO into light and medium distillate such as usable diesel fuel, the processes generally comprising the steps of: boiling the PBWO to dehydrate the PBWO, heating the PBWO to produce PBWO hydrocarbon vapor, contacting the PBWO hydrocarbon vapor with a catalyst, and cooling the resultant vapor to liquid form through heat exchangers to produce light and medium distillate.

A method for re-refining used oils comprises contacting feedstock comprising purified used oil with extraction solvent to perform continuous liquid-liquid solvent extraction, to produce an extract stream comprising the extraction solvent and an extract dissolved in the extraction solvent. The feedstock and the extraction solvent are agitated by a variable speed agitator during the solvent extraction at a selected agitation speed. The extract is separated from the extraction solvent and subjected to a continuous flow liquid phase hydrogenation treatment to produce an oil product. A system for performing the method includes a purification unit for purifying the used oil; an extraction column for extracting the extract from the feedstock; and a continuous flow liquid phase hydrogenation unit. The extraction column comprises an agitator configured to agitate the feedstock and the extraction solvent flowing through the extraction column at a variable agitation speed.

The invention relates to a method for lowering the content of polycyclic aromatic hydrocarbons (PAH) in a used lubricant composition, in which said used lubricant composition passes over activated carbon, said method not comprising a solvent extraction step.

A method is provided for reprocessing a petroleum-based waste oil feedstock into diesel fuel. The method includes forming a treated feedstock by (a) filtering the feedstock, thereby removing solids and metals from the feedstock, and (b) dehydrating the feedstock; vaporizing the treated feedstock to produce an oil vapor; passing the oil vapor through at least one catalyst bed and subsequently through a cooler, thereby converting the oil vapor to a hydrocarbon liquid product with a diesel product boiling point range; and removing contaminants from the hydrocarbon liquid product, wherein the contaminants are selected from the group consisting of particulates and color precursors.

A method for the regeneration of used lubricating oils to produce lubricant base oils includes the steps of (a) removing resin and impurities by distillation, (b) catalytic oxidation treatment and (c) adsorption process. The method can efficiently reduce the color, metal ions, and sulfur content under mild reaction conditions at low cost and obtain high yield of regenerated oil above 85 wt. %.