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.....

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existence and been replaced by fluid catalytic crackers and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.

When an expansion is joint needed on the shell side of a shell and tube heat exchanger?

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We are having proplem with the persperation smell in ETT/ECHO room in our cardiac hospital.The 2 Ton of AC is not conditioning the environment. We have to use exhaust fan to through out of the room bad air. Could anyone suggest how to coup with this effectively using chemical engineering. Any permanent solution to neutralise the bad smell.The Air freshners are not doing enough instead making a bad odour.

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Question 88 - In the calculation of the growth of bacteria, colony forming unit (CFU) in serial dilution is used. In a laboratory, viable count assay is used to estimate CFU. Formula applied is CFU / mL = (number of colonies x dilution) / (amount plated, in unit mL). Acceptable plate count is either between 20 and 200 or between 30 and 300 according to 2 different references. A wastewater sample of 200 ml is added to and mixed with 1.8 L of sterile water. Another 200 ml of the mixture is added to and mixed with 1.8 L of sterile water. (a) Calculate the dilution of first mixture and the dilution of the second mixture. (b) 100 microlitres of wastewater samples from the first mixture and the second mixture are placed separately on 2 different alga plates. The first plate has 250 colonies and the second plate has 23 colonies. Calculate the average CFU / mL.

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Question 33 – By using Excel program either on laptop or desktop PC, solve the differential equation dy / dx = -2y + x + 4 with h = 0.005, initial values : x = 0, y = 1. The 4th order Runge-Kutta method provides : y(N + 1) = y(N) + (1/6) (k1 + 2k2 +2k3 + k4), k1 = h [ -2y(N) + x(N) + 4 ], k2 = h { -2 [ y(N) + k1 / 2 ] + x(N) + h / 2 + 4 }, k3 = h { -2 [ y(N) + k2 / 2 ] + x(N) + h / 2 + 4 }, k4 = h { -2 [ y(N) + k3 ] + x(N) + h + 4 }. What is the value of y at x = 0.5?

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What are some good strategies for curing tube vibration in shell and tube exchangers?

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What are the advantages and disadvantages of using gear pumps?

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what is the differance between Horizental and vertical heat exchanger?

11 Answers   Bihar Caustic and Chemicals,

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What is the method of determining maximum differential pressure during hydro testing of shell and tube heat exchangers?

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hai can anyone send me soft copy of o.p gupta or tell me downloading link please please at saify_0@hotmail.com

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What is the symbol of sodium?

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how much maximum power can be generated by 320v, 10kg-cm synchronus motor if shaft is roteted mechanically at 50 to 60 rpm?

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Explain what are the advantages of using gear pumps?

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