System for producing an American Petroleum Institute Standards Group III Base Stock from vacuum gas oil
A system for producing American Petroleum Institute Standards Group III Base Stock from vacuum gas oil, by injecting hydrogen, heating, partially saturating the vacuum gas oil through a plurality of hydrogen reactors connected in series with a liquid hourly space velocity (LHSV) −1 of from 0.5 to 2.5, forming a saturated heated base oil, and coproduct. The system fractionates the saturated heated base oil to while simultaneously refluxing a cooled fuel oil fraction forming an American Petroleum Institute Standards Group III Base Stock with less than 0.03% sulfur, with greater than 90% saturates and a viscosity index greater than 120 as defined by ASTM D-2270, a viscosity from 2 to 10 centistokes as defined by ASTM D-445 a boiling range from 600 degrees F. to 1050 degrees F., and a cold crank viscosity (CCS) between 1200 and 5000 centipoise at −25 degrees C. and as defined by ASTM D-5293.
1. A system for producing an American Petroleum Institute Standards Group III Base Stock from vacuum gas oil, comprising:
a. a conduit receiving a vacuum gas oil with a boiling point range from 450 degrees Fahrenheit to 1050 degrees Fahrenheit as defined by ASTM D-86;
b. a first heater fluidly connected to the conduit increasing temperature of the vacuum gas oil to a temperature from 450 degrees Fahrenheit to 600 degrees Fahrenheit, forming a heated vacuum gas oil;
c. a pump installed prior to the first heater, a fresh hydrogen injector and a recycle hydrogen injector simultaneously increasing pressure on the heated vacuum gas oil from 50 psig to a pressure from 1000 psig and 1500 psig by injection of hydrogen, wherein the fresh hydrogen injector comprises a nozzle that engages a flow control valve further in communication with a flow meter and a high-pressure pump and a hydrogen vaporizer for receiving liquid hydrogen from a liquid hydrogen reservoir;
d. a plurality of hydrogen reactors connected in series, each to a heater, each hydrogen reactor having a liquid hourly space velocity (LHSV) −1 from 0.5 to 2.5, for first demetallizing and heating and then further reacting and heating the heated vacuum gas oil to form a fully saturated heated base oil, wherein the saturated heated base oil with hydrogen has a temperature from 600 degrees Fahrenheit to 800 degrees Fahrenheit;
e. a high-pressure flash drum connected to the final hydrogen reactor forming (i) a recycle overhead at a pressure from 1000 psig to 1500 psig; (ii) a fully saturated base oil, (iii) contaminants, and (iv) a coproduct at a high pressure from 1000 psig to 1500 psig;
f. a low-pressure flash drum removing additional contaminants from the fully saturated base oil producing contaminant free saturated heated base oil and coproduct; and
g. a fractionation tower receiving contaminant free saturated heated base oil and coproduct and steam to remove a light oil fraction with an initial boiling point less than 600 degrees F. while simultaneously refluxing, forming an API Standards Group III Base Stock with less than 0.03 percent sulfur, greater than 90 percent saturates and a viscosity index greater than 120 as defined by ASTM D-2270 and a viscosity range from 2 to 10 centistokes as defined by ASTM D-445 with a boiling range from 600 degrees F. to 1050 degrees F. as defined by ASTM D-86, and a cold crank viscosity (CCS) between 1200 and 5000 centipoise at minus 25 degrees C. and as defined by ASTM D-5293.
2. The system of claim 1 , further comprising a feed effluent heat exchanger to exchange energy from the American Petroleum Institute Standards Group III Base Stock is with the feedstock vacuum gas oil reducing temperature of the American Petroleum Institute Standards Group III base stock from 500 degrees Fahrenheit to 300 degrees Fahrenheit.
3. The system of claim 2 , further comprising a cooling water exchanger to receive warm American Petroleum Institute Standards Group III Base Stock from the feed effluent heat exchanger and reduces the temperature by 100 degrees Fahrenheit to 150 degrees Fahrenheit and then transfers the cooled American Petroleum Institute Standards Group III Base Stock to storage or transport.
4. The system of claim 1 , further comprising a metallic catalyst installed in each of the hydrogen reactors, wherein the metallic catalyst is selected from at least one of the group consisting of: cobalt, nickel, and molybdenum.
5. The system of claim 1 , wherein the recycle hydrogen injector comprises:
a. a recycle nozzle;
b. a recycle flow meter connected to the recycle nozzle in series;
c. a hydrogen compressor connected to the recycle flow meter;
d. a second stage knockout drum separating contaminated water;
e. a first stage knockout drum separating contaminated water and naphtha;
f. a water-cooled exchanger;
g. a high-pressure wash water injector providing a psig from 1400 to 1600 psig receiving water; and
h. a recycle overhead connected to the high-pressure wash water injector.