--%>
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 : What are various structure based

    This classification of polymers is based upon how the monomeric units are linked together. Based on their structure, the polymers are classified as: 1. Linear polymers: these are the polymers in which monomeric units are linked together to form long straight c

    		•
  • 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 : Problem on Clausius equation of state

    If a gas can be described by the Clausius equation of state: P (V-b) = RT Where b is a constant, then:  (a) Obtain an expression for the residual vo

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

    how 0.5N HCL is prepared for 10 littre solution

    		•
  • Q : How much phosphorus is in superphosphate

    Superphosphate has the formulate: CaH4 (PO4)2 H2O calculate the percentage of Phosphorus in this chemical. Show your calculations

    		•
  • Q : How haloalkanes are prepared from

    This is the common method for preparing haloalkanes in laboratory. Alcohols can be converted to haloalkanes by substitution of - OH group with a halogen atom. Different reagents can be used to get haloa

    		•
  • Q : Calculating total vapour pressure

    Select the right answer of the question. The vapour pressure of two liquids P and Q are 80 and 600 torr, respectively. The total vapour pressure of solution obtained by mixing 3 mole of P and 2 mole of Q would be: (a) 140 torr (b) 20 torr (c) 68 torr (d) 72 torr

    		•
  • Q : Molarity of Nacl solution When 5.85 g

    When 5.85 g of NaCl (having molecular weight 58.5) is dissolved in water and the solution is prepared to 0.5 litres, the molarity of the solution is: (i) 0.2 (ii) 0.4 (iii) 1.0 (iv) 0.1

    		•
  • Q : Organic and inorganic chemistry Write

    Write down a short note on the differences between the organic and inorganic chemistry?

    		•
  • Q : Problem on reversible process a. For a

    a. For a reversible process involving ideal gases in a closed system, Illustrate thatΔS = Cv ln(T2/T1) for a constant volume process ΔS = Cp ln(T2/T1) for a constant pressu

    		•