Why is steam added into the cracker in thermal cracking?
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Answer / nk
the DILUTION STEAM ADDING IN THERMAL CRACKING TO DECREACE THE VAP.PRESSURE OF THE HYDROCARBON....and it also helps in decreasing the rate of coke formation.....
Is This Answer Correct ? | 8 Yes | 1 No |
Answer / eugene
Thermal crackers to produce cracked gasoline from heavy gas
oils in petroleum refineries have largely gone out of
existence and been replaced by fluid catalytic crackers and
hydrocrackers.
However, when they were used back in the 1930's and 1940's,
steam was always injected into the process tubes of the
fired heaters that raised the temperature of the gas oils
to the point where they cracked into smaller molecules ...
and the purpose of the steam was to inhibit the rate of
coking in the heater's process tubes so that the heaters
could stay online continuously for some months.
Today's delayed coking units in petroleum refineries are
designed to produce and lay down saleable coke in very
large vertical drums. In those delayed cokers, steam is
again used in the feed heaters to inhibit and delay the
coking from occuring until the heated, vaporized feed
reaches the large vertical coke drums.
Is This Answer Correct ? | 4 Yes | 0 No |
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