VGO Technology
Vertex Refining LA, LLC manages a non-hazardous used oil refinery perfectly positioned on the west bank of the Mississippi River in Jefferson Parish, Louisiana. The refinery resides on 4.4 acres at the corner of River Road and Barataria Boulevard in Marrero, LA. Used motor oil (UMO) is brought into the facility by semi-truck, railcar, or by barge and is re-refined through three successive distillation steps, which stripe and convert roughly 4,200 barrels per day of collected UMO into vacuum gas oil, asphalt extender and fuel condensate. The final vacuum gas oil is sold into the marine diesel market, as cutter stock, and for energy recovery. The asphalt extender is utilized in roofing products, road paving applications. The fuel condensate is burned in industrial furnaces.
Distillation Process
From the feed tanks, the used motor oil temperature is raised through a series of preheat exchangers and re-boilers before reaching an atmospheric flash drum where the water and light hydrocarbons are evaporated. The vapors from the flash drum travel overhead through a condenser and are further split into water and fuel oil downstream in an oil-water phase separator. The uncondensed vapors from the flash drum are sent and oxidized in the process heater in the refinery.
The bottom mixture from the atmospheric flash drum is pumped on a continuous basis into the vacuum distillation tower whereby the pressure above the bottom mixture to be distilled is reduced to less than its vapor pressure, causing the evaporation of the liquids with the lowest boiling points. This is done by recirculating the tower bottoms through a process heater, which raises the temperature of the mixture to the desired point, separating the specific fractions under vacuum. The light hydrocarbon vapors rise to the top of the tower where they are condensed and the heavier hydrocarbons liquids fall to the bottom. The medium vacuum gas oil (MVGO) is drawn off the tower, condensed and routed to storage with a small fraction being returned to the tower. The uncondensed vapors from the vacuum distillation tower are condensed downstream in a water-cooled heat exchanger, producing a second light hydrocarbon stream similar in chemical and physical properties to the fuel oil stream taken off during the atmospheric distillation step. The uncondensed vapors from the water-cooled heat exchanger are oxidized in the process heater in the refinery.
The wiped film evaporator takes the bottoms from the vacuum distillation tower and splits them into another light hydrocarbon stream, heavier vacuum gas oil (HVGO), and a bottom asphalt product. The bottom mixture from the tower is placed into the top of the wiped film evaporation chamber. This chamber has a heated outer surface and a centered vertical jacketed condenser. The short distance between the heating and condensing surfaces minimizes the pressure drop across the system, which allows evaporation in pressure ranges below 1mbar. A small amount of overhead light hydrocarbon vapors from the wiped film evaporator are condensed and combined with the other two light hydrocarbon streams from the atmospheric flash drum and the vacuum distillation tower. The vapor liquefied on the internal condenser is collected as HVGO and mixed together with the MVGO from the vacuum distillation tower and routed to storage. The remaining undistilled product is collected as an asphalt extender.
