Method of producing high softening point pitch
View Patent ↗The present invention provides a way to increase the softening point of heavier hydrocarbons in a relatively low cost and low pressure process using superheated steam to i) increase the carbon yield of the heavier hydrocarbons, while simultaneously ii) removing volatile components with a steam stripping process.
1. A process for increasing the softening point and increasing the carbon yield of hydrocarbon materials which comprises:
a) directly contacting at least one stream of the hydrocarbon materials with a heated stream comprising steam superheated under temperature, contact times, and superficial velocity conditions sufficient i) to increase the softening point of the hydrocarbon materials and ii) to provide a desired volume of liquid product in at least one suitable disengaging vessel, and a remaining volume of volatile overhead product and steam;
b) condensing the volatile overhead product in at least one stage;
c) recovering at least part of the volatile overhead product as distillate;
d) condensing the steam in a second stage, and
e) recovering a bottoms fraction containing the liquid products,
wherein the contacting of the hydrocarbon stream and the superheated steam is carried out in at least one atomizing nozzle, wherein the hydrocarbon materials pass through the atomizing nozzle; and wherein the at least one atomizing nozzle substantially surrounds a supply of the hydrocarbon material with the stream of the superheated steam,
wherein heated stream of steam is vaporized at temperatures ranging from 450 to 1800° F., a vapor rate of 0.1 to 10 pounds heated vapor per pound of charge, and a superficial velocity of about 5.5 feet per second or less, to provide vaporization temperatures ranging from about 400 to 1000° F., and the hydrocarbon material is contacted with the superheated stream of steam for a period ranging from 0.1 to 2 seconds.
2. The process of claim 1 , which is carried out in the absence of process fouling.
3. The process of claim 1 , wherein the vaporization temperatures, vapor rate, superficial velocity, and contact times are adjusted to provide a volume reduction of the total amount of the hydrocarbon materials ranging from 20 to 95 wt. %.
4. A process for increasing the softening point and increasing the carbon yield of hydrocarbon materials which comprises:
a) directly contacting at least one stream of the hydrocarbon materials with a heated stream comprising steam superheated under temperature, contact times, and superficial velocity conditions sufficient i) to increase the softening point of the hydrocarbon materials and ii) to provide a desired volume of liquid product in at least one suitable disengaging vessel, and a remaining volume of volatile overhead product and steam;
b) condensing the volatile overhead product in at least one stage;
c) recovering at least part of the volatile overhead product as distillate;
d) condensing the steam in a second stage, and
e) recovering a bottoms fraction containing the liquid products,
wherein the contacting of the hydrocarbon stream and the superheated steam is carried out in at least one atomizing nozzle, wherein the hydrocarbon materials pass through the atomizing nozzle; and wherein the at least one atomizing nozzle substantially surrounds a supply of the hydrocarbon material with the stream of the superheated steam,
wherein the superheated stream of steam is introduced in the atomizing nozzle at temperatures ranging from 700 to 1100° F., at a rate of 2 to 3 pounds per pound charge, and a superficial velocity of at least about 3 feet per second to provide vaporization temperatures in the atomizing nozzle ranging from about 550 to about 650° F., and the hydrocarbon material is contacted with the stream of superheated steam for a period ranging from 0.25 to 0.5 seconds.
5. The process of claim 1 , wherein heated steam is recovered from the volatile overhead product and recycled to the atomizing nozzle.
6. The process of claim 1 , wherein the hydrocarbon material comprises at least one of FCC/RCC slurry oil, asphalt or petroleum pitch.
7. A process for increasing the softening point and increasing the carbon yield of hydrocarbon materials which comprises:
a) directly contacting at least one stream of the hydrocarbon materials with a heated stream comprising steam superheated under temperature, contact times, and superficial velocity conditions sufficient i) to increase the softening point of the hydrocarbon materials and ii) to provide a desired volume of liquid product in at least one suitable disengaging vessel, and a remaining volume of volatile overhead product and steam;
b) condensing the volatile overhead product in at least one stage;
c) recovering at least part of the volatile overhead product as distillate;
d) condensing the steam in a second stage, and
e) recovering a bottoms fraction containing the liquid products,
wherein the contacting of the hydrocarbon stream and the superheated steam is carried out in at least one atomizing nozzle, wherein the hydrocarbon materials pass through the atomizing nozzle; and wherein the at least one atomizing nozzle substantially surrounds a supply of the hydrocarbon material with the stream of the superheated steam,
wherein the hydrocarbon materials comprise raw used lubricating oil with light ends having a boiling point of less than about 210° F.
8. The process of claim 1 , wherein the hydrocarbon material is preheated prior to directly contacting with the superheated steam.
9. The process of claim 8 , wherein the hydrocarbon material is at least partially fractionated or flashed to remove a majority, by weight, of at least one of chemical solvents boiling in the gasoline boiling range and gasoline boiling range components prior to being contacted by the steam.