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existence and been replaced by fluid catalytic crackers and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.

Explain the different types of equipments for the conveyance of solids?

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which is more effective , a single extraction with a large volume of solvent or several small volume extractions? Explain.

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what is difference between precipitation and crystalisation

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If the refrigerator is left open in closed room, What will be the effect on room temp.?

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ENGINEERING ECONOMY - EXAMPLE 7.1 : In engineering economy, the future value of first year is FV = PV (1 + i). For second year it is FV = PV (1 + i) (1 + i). For third year it is FV = PV (1 + i) (1 + i)(1 + i) where FV = future value, PV = present value, i = interest rate per period, n = the number of compounding periods. By induction, what is the future value of $1000 for 5 years at the interest rate of 6 %?

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Suggest the best book for barc written test guide me the syllabus

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Question 93 - In thin layer chromatography (TLC), let retention factor Rf = (distance traveled by solute) / (distance traveled by solvent). Silica gel is used as stationary phase which is more polar than the hexane solvent as mobile phase. If the Rf values of 3 solutes A, B and C are 1.5, 0.75 and 1 respectively, compare the polarities of A, B and C with reasons.

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DIFFERENTIAL EQUATIONS - EXAMPLE 20.1 : 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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Question 43 - In a non-dilute absorber, the inlet gas stream consists of 8 mol % carbon dioxide in nitrogen. By contact with room temperature water at atmospheric pressure, 65 % of the carbon dioxide from a gas stream has been removed. (a) Find the mole ratio of carbon dioxide and nitrogen gases at inlet and outlet gas streams. (b) The Henry’s Law provides y = 1640 x for carbon dioxide in water. Find the mole ratio when x = 0.0000427. Mole ratio is y / (1 - y) for y.

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What is difference between Overall heat transfer coeficient & individual heat transfer coefficient

4 Answers   CVSR, NFTDC,

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What are the strategies acquired to cure tube vibration and exchangers in a shell?

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QUANTUM BIOLOGY - EXAMPLE 33.2 : (a) In a biomolecule, ATP hydrolysis will produce 3 kcal / mol to 60 kcal / mol of energy, according to energy scale. Find the range of such energy generation if 2 moles of molecules involved. (b) A formula is given by ln P = ln a + b ln W where P = metabolic rate, W = body size, a = dependent of taxa, b = scaling exponent. If b is approximately 1 for plant, and b is approximately 0.75 for animal, find the relationship of P as a function of a and W in plant.

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