--%>
Assignment Help - homework help

Linde liquefaction process

Liquefied natural gas (LNG) is produced using a Linde liquefaction process from pure methane gas at 3 bar and 280 K (conditions at point 1 in figure below). A three-stage compressor with interceding is used to compress the methane to 100 bar (point 2). The first stage compresses the gas from 1 bar to 5 bar, the second stage from 5 bar to 25 bar, and the tiiird stage from 25 bar to 100 bar. Between stages the gas Is isobarically cooled to 280 K. Each stage of the compressor can be assumed to operate reversibly and adiabaticaliy. The methane leaving the cooler is at 100 bar and 210 K (point 3). The flash dram is adiabatic and operates at! bar. The recycled methane leaving the heat exchanger (point 5') is at I bar and 200 K.

a) Calculate the fractions of vapour and liquid leaving the flash drum {Hint: write balance equations around the subsystem consisting of the heat exchanger, throttle valve and flash drum).

b) Calculate the temperature at the inlet of the compressor (point I).

c) Calculate the amount of work required for each kilogram of methane that passes through the compressor.

d) Calculate the amount of compressor work required for each kilogram of LNG produced.

e) Calculate

i) the heat removal after the first and second stages of the compressor,
ii) the heat removed in the cooler, and
iii) the heat exchanged in the heat exchanger.

Express all values in kJ/kg of methane that passes through the compressor.

Data: The thermodynamic properties of methane are given in the attached diagram.

71_diagram.jpg

   Related Questions in Chemistry

  • Q : Calculating molarity of a solution

    Select the right answer of the question .The molarity of a 0.2 N N2Co3 solution will be: (a) 0.05 M (b) 0.2 M (c) 0.1 M (d)0.4 M

    		•
  • Q : Molecular substances what are the most

    what are the most important inorganic molecular substances for living beings?

    		•
  • Q : Pressure Phase Diagrams The occurrence

    The occurrence of different phases of a one component system can be shown on a pressure temperature. The phases present in a one line system at various temperatures can be conveniently presented on a P- versus-T diagram. An example is pro

    		•
  • Q : Explain Rotational Vibrational Spectra

    The infrared spectrum of gas samples shows the effect of rotational-energy changes along with the vibrational energy change.As we know from the interpretations given to thermodynamic properties of gases, gas molecules are simultaneously rotating and vibrating. It follows that an absor

    		•
  • Q : Normality how 0.5N HCL is prepared for

    how 0.5N HCL is prepared for 10 littre solution

    		•
  • Q : Polyhalogen compounds we need 10

    we need 10 examples for the polyhalogen compounds....please help me....need it urgently...

    		•
  • Q : Explain Solid Compound Formation. In

    In some two component, solid liquid systems, a solid compound forms.In systems in which the components have an interaction for such other, a solid state compound of the two compounds of the two components can form.Formic acid and formaide form a solid state, one-to-one com

    		•
  • Q : Calculating amount of Sodium hydroxide

    Choose the right answer from following. The amount of NaOH in gms in 250cm3 of a0.100M NaOH solution would be : (a) 4 gm (b) 2 gm (c) 1 gm (d) 2.5 gm

    		•
  • Q : Lowering of vapour pressure Help me to

    Help me to go through this problem. Lowering of vapour pressure is highest for: (a) urea (b) 0.1 M glucose (c) 0.1M MgSo4 (d) 0.1M BaCl2

    		•
  • Q : Problem on partial pressure i) Show

    i) Show that the equilibrium constant Kp for the reaction CaCo3(s) ↔ CaO(s) +CO2(g)is about unity (i.e. = 1.0) at 895 °C.ii) If two grams of calcium carbonate are pl

    		•