Methanol is contained within a storage tank. There was a earthquake that ruptured the connection of...

  

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Methanol is contained within a storage tank. There was a earthquake that ruptured the connection of a 0.1016m diameter loading line exiting the bottom of the vessel. The initial liquid level of the vessel is 6 m above iversity of the West Indies Course Code CHNG 3014 2013/2014 Page 3 the base of the vessel. The pressure above the level of the liquid is 0.2 bar g. The liquid pool spreads within the bunded region that can be assumed circular with a diameter of 25m. The liquid pool was ignited and resulted in a pool fire. The liquid pool is ignited 30 minutes after the pool reaches its maximum diameter. Determine a. The maximum discharge rate. [3 Marks] b. The evaporation rate in mass per second and the amount of vapor evaporated after 15 minutes [4 Marks] c. The burning rate in mass per second. [4 Marks] d. The distance away from the pool that the probability of a first degree burn is 50% after 60s of exposure. [10 Marks] e. What is a first degree burn and comment on this type of incident? [4 Marks] STATE ALL ASSUMPTIONS CLEARLY. For entrance and exit losses K -0.5 and K = 1.0 respectively. Density of liquid methanol 791.8 kg m-3 Viscosity - 5.9 x 104 Pas Storage Temperature 298K Boiling point of methanol 337.7 K The 10m high wind velocity 2 m s psat -21.78 KPa Enthalpy of vaporization of methanol - 1102.4 kJ kg -1 Heat of combustion of methanol 22.7 MJ kg-1 Specific heat capacity of methanol (1) 2.484 kJ kg -1 K - assumed constant until its boiling point. D Diffusivity 0.84 x 10-5 m s -1 Use a radiation fraction - 0.35 and a relative humidity of 80%. 1 bar = 100kPa H2 Fire Receptor x 1+ Pool D/2 Methanol is contained within a storage tank. There was a earthquake that ruptured the connection of a 0.1016m diameter loading line exiting the bottom of the vessel. The initial liquid level of the vessel is 6 m above iversity of the West Indies Course Code CHNG 3014 2013/2014 Page 3 the base of the vessel. The pressure above the level of the liquid is 0.2 bar g. The liquid pool spreads within the bunded region that can be assumed circular with a diameter of 25m. The liquid pool was ignited and resulted in a pool fire. The liquid pool is ignited 30 minutes after the pool reaches its maximum diameter. Determine a. The maximum discharge rate. [3 Marks] b. The evaporation rate in mass per second and the amount of vapor evaporated after 15 minutes [4 Marks] c. The burning rate in mass per second. [4 Marks] d. The distance away from the pool that the probability of a first degree burn is 50% after 60s of exposure. [10 Marks] e. What is a first degree burn and comment on this type of incident? [4 Marks] STATE ALL ASSUMPTIONS CLEARLY. For entrance and exit losses K -0.5 and K = 1.0 respectively. Density of liquid methanol 791.8 kg m-3 Viscosity - 5.9 x 104 Pas Storage Temperature 298K Boiling point of methanol 337.7 K The 10m high wind velocity 2 m s psat -21.78 KPa Enthalpy of vaporization of methanol - 1102.4 kJ kg -1 Heat of combustion of methanol 22.7 MJ kg-1 Specific heat capacity of methanol (1) 2.484 kJ kg -1 K - assumed constant until its boiling point. D Diffusivity 0.84 x 10-5 m s -1 Use a radiation fraction - 0.35 and a relative humidity of 80%. 1 bar = 100kPa H2 Fire Receptor x 1+ Pool D/2