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

A method for self-heat-extracting flash evaporation of a sulfuric acid alkylation reaction product, comprising the following steps:

• (a) introducing a sulfuric acid alkylation reaction product to a coalescence-vaporization unit;
• (b) distributing the sulfuric acid alkylation reaction product throughout the coalescence-vaporization unit thereby producing a preliminarily distributed sulfuric acid alkylation product;
• (c) coalescing and vaporizing the preliminarily distributed sulfuric acid alkylation reaction product to cause preliminary vaporization of a hydrocarbon therein, thereby taking heat away and separating a preliminarily separated alkylation reaction product comprising hydrocarbon from the sulfuric acid,
• wherein said preliminarily distributed sulfuric acid alkylation reaction product is coalesced through one or more parallel coalescence-vaporization assemblies comprising a coalescence module and a vaporization module installed in an annular gap of a support framework comprising a plurality of concentric cylinders,
• wherein said preliminarily distributed sulfuric acid alkylation reaction product flows through 1-50 mm holes through and around said concentric cylinders to reach said coalescence module and said vaporization module,
• wherein a ratio of a perforated area to an unperforated area in a wall portion of one of said concentric cylinders is from 1:1 to 1.5:1, and
• wherein when said preliminarily distributed sulfuric acid alkylation reaction product flows through said coalescence module, said coalescence module coalesces the preliminarily distributed sulfuric acid alkylation reaction product;
• and
• (d) subjecting the preliminarily separated alkylation reaction product obtained in step (c) to reinforced separation by flowing said preliminarily separated alkylation reaction product through 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,
• wherein said preliminarily separated alkylation reaction product flows through holes opened through the circular arc plate, the circular arc corrugated plate, the circular arc stepped plate, or the bellmouth-shaped tubular structure having a diameter of 1 to 50 mm, said holes creating a ratio of a perforated area to an unperforated area of the circular arc plate, the circular arc corrugated plate, the circular arc stepped plate, or the bellmouth-shaped tubular structure from 1:1 to 2:1, and
• wherein the hydrocarbon is further vaporized to take heat away from the preliminary separated alkylation reaction product and further separate the hydrocarbon from the sulfuric acid in the preliminarily separated alkylation reaction product.