Method and apparatus for self-heat-extracting flash evaporation of sulfuric acid alkylation reaction product

Patent metadata

Field	Value
Publication number	US-2020165530-A1
Application number	US-201916665233-A
Country	US
Kind code	A1
Filing date	Oct 28, 2019
Priority date	Nov 28, 2018
Publication date	May 28, 2020
Grant date	—

Abstract

The present disclosure relates to a method and an apparatus for self-heat-extracting flash evaporation of a sulfuric acid alkylation reaction product. There is provided a method for self-heat-extracting flash evaporation of a sulfuric acid alkylation reaction product. One step is to coalesce and vaporize a preliminarily distributed sulfuric acid alkylation reaction product to cause preliminary vaporization of a hydrocarbon therein, thereby taking heat away and preliminarily separating the hydrocarbon from sulfuric acid. Another step is to subject the preliminarily separated alkylation reaction to reinforced separation, where the hydrocarbon is further vaporized to take heat away and further separate the hydrocarbon from the sulfuric acid. There is also provided an apparatus for self-heat-extracting flash evaporation of a sulfuric acid alkylation reaction product.

First claim

1 - 10 . (canceled)

11 . A method for self-heat-extracting flash evaporation of a sulfuric acid alkylation reaction product, comprising the following steps:
(a) coalescing and vaporizing a preliminarily distributed sulfuric acid alkylation reaction product to cause preliminary vaporization of a hydrocarbon therein, thereby taking heat away and preliminarily separating the hydrocarbon from sulfuric acid; and (b) subjecting the preliminarily separated alkylation reaction product obtained in step (a) to reinforced separation, wherein the hydrocarbon is further vaporized to take heat away and further separate the hydrocarbon from the sulfuric acid.

12 . The method of claim 11 , wherein, in step (a), the sulfuric acid alkylation reaction product is preliminarily distributed through a liquid distributor and a bubble cap plate; and coalescence and vaporization are performed using a coalescence-vaporization unit, wherein the sulfuric acid alkylation reaction product flows into a center of a coalescence-vaporization assembly and, in its radial direction, flows sequentially through an inner wall of a support framework, a coalescence module, a vaporization module, and an outer wall of the support framework.

13 . The method of claim 12 , wherein, in step (b), reinforced separation is performed using a reinforced separation unit, wherein acid droplets which are not separated timely are spread by an acid-hydrocarbon separation-coalescence baffle in the reinforced separation unit into a film on a surface thereof, adhered and detached, thereby further separating the hydrocarbon from the sulfuric acid; while the hydrocarbon is further vaporized, takes heat away, and is discharged from a gas phase outlet.

14 . An apparatus for self-heat-extracting flash evaporation of a sulfuric acid alkylation reaction product, comprising:
a liquid distributor and a bubble cap plate disposed in a flash tank for preliminary distribution of a sulfuric acid alkylation reaction product; a coalescence-vaporization unit disposed below the liquid distributor and the bubble cap plate in the flash tank for coalescing and vaporizing the sulfuric acid alkylation reaction product after the preliminary distribution, so that a hydrocarbon therein is preliminarily vaporized to take heat away and preliminarily separate the hydrocarbon from sulfuric acid; and a reinforced separation unit disposed below the coalescence-vaporization unit in the flash tank for reinforced separation of the preliminarily separated alkylation reaction product, wherein the hydrocarbon is further vaporized and takes heat away, thereby further separating the hydrocarbon from the sulfuric acid.

15 . The apparatus of claim 14 , wherein the coalescence-vaporization unit is consisting of one or more coalescence-vaporization assemblies arranged in parallel; and the coalescence-vaporization assembly comprises a support framework, a coalescence module and a vaporization module, wherein the support framework is a mesh structure consisting of a plurality of concentric cylinders; the coalescence module and the vaporization module are installed in an annular gap between the concentric cylinders; small holes having a diameter of 0-50 mm are opened through and around walls of the cylinders; and a ratio of a perforated area to an unperforated area of the wall is 1 to 1.5:1.

16 . The apparatus of claim 15 , wherein a height of the coalescence-vaporization assembly is ⅙ to ¼ of a height of the flash tank; the coalescence module and the vaporization module are made of polymer fibers or modified metal fibers, wherein the coalescence module has a fiber diameter of 70-350 μm, and the vaporization module has a fiber diameter of 350-600 μm; wherein the fibers are alternately arranged in an irregular manner and are filled in the modules in a multi-stage porosity mode, wherein the multi-stage porosity mode is characterized by a total porosity of 50 to 95%, a first stage porosity of 50 to 70%, a stage-by-stage increment in porosity of 5% to 15% from inside to outside, a porosity of the coalescence module of less than 70-85%, a porosity of the vaporization module of not less than 85%, and an identical volume occupied by each module.

17 . The apparatus of claim 16 , wherein the reinforced separation unit is consisting of one or more acid-hydrocarbon separation-coalescence baffles and support members, and is disposed below the coalescence-vaporization unit, wherein the separation-coalescence baffle comprises a circular arc plate, a circular arc corrugated plate, a circular arc stepped plate or a bellmouth-shaped tubular structure formed by the above-mentioned circular arc plate structure and a cylindrical welded member; holes opened through the plate have a diameter of 0 to 50 mm; and a ratio of a perforated area to an unperforated area of the plate is 1 to 2:1.

18 . The apparatus of claim 17 , wherein the separation-coalescence baffle is made of metal or non-metal; wherein an acidophilic fiber strand winds around a surface thereof, or tongue pieces are welded on the surface, with a winding or welding pitch on the surface of 5 to 100 mm, wherein the holes in the plate are bypassed during installation of the fiber strand or tongue pieces.

19 . The apparatus of claim 18 , wherein the acidophilic fiber strand is woven from one or more acidophilic fibers, wherein the fiber has a diameter of 100 to 500 μm, and the fiber strand has a diameter of 10 to 500 mm, wherein the acidophilic fiber strand winds in an inner surface of the circular arc plate in a circumferential direction; the tongue piece has a square, triangular, semi-elliptical, trapezoidal or semi-circular shape; the tongue piece has a height of 10-30 mm, which is the largest distance of the tongue piece from the baffle; the tongue piece has a thickness of 1-3 mm; the tongue piece is installed at an angle in the range of 15° and 75° in relation to the baffle; and a surface of the tongue piece may be treated with an acidophilic coating.

20 . The apparatus of claim 14 , wherein the flash tank comprises a reaction product inlet, a hydrocarbon phase outlet and an acid phase outlet.

Assignees

• Univ East China Science & Tech

Inventors

• Bai Zhishan
• Zhang Yan
• Yang Xiaoyong
• Luo Huiqing

Classifications

• C10G7/00 Primary

  Distillation of hydrocarbon oils · CPC title

• C10G2300/4081

  Recycling aspects · CPC title

• C10G2300/1081

  Alkanes · CPC title

• C10G2300/70

  Catalyst aspects · CPC title

• C10G2300/1088

  Olefins · CPC title