Heat cryogenic liquids directly with steam?
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Is LNG used with an intermediate medium or seawater for vaporization or submerged combustion heat exchange, rather than direct heat exchange with steam, because of ice formation on the heat exchange tubes, or for some other reason?
Using a vaporizer inherently results in the waste of cold energy; by adding steam heat exchange, wouldn’t that lead to even higher energy consumption, greater investment costs, and further waste of money?
Some medium-fluid heat exchangers use steam to heat the medium fluid; for example, methanol is used as such a medium. What I wonder is why steam isn’t used for direct heating in this case?
Although steam can be liquefied to release heat, the liquid formed after liquefaction adheres to the walls of the heat exchange tubes, where it tends to form frost, thereby affecting heat transfer!
Because methanol can be used as an antifreeze; it has a low freezing point and will not cause blockages due to freezing
Steam should form a layer of ice on the surface of the vaporizer, affecting heat transfer. For example, in summer, air-cooled vaporizers can sometimes freeze up when used continuously, due to the high moisture content in the air. It must be easier to freeze with steam, right?