Risk management, Fragility, Uncertainties, Fault Tolerant Systems, Explosion

1. A propane tank is located 100 m away from the nearest buildings. The fragility to explosion can be expressed by p = 0 for I < 0.7 MPa • s p = aI for 0.7 < I < 1.3 MPa • s p = 1 for I > 1.3 MPa • s Accounting for various release and ignition scenarios, including uncertainties, the estimated probability distribution of impulses resulting from such explosions is given by the following set of values: I (MPa • s) 0.1 0.3 0.5 0.7 0.9 1.2 p 0.06 0.1 0.4 0.3 0.1 0.04 Supposing that you can improve the building so that you can affect the threshold of damage, increasing it above 0.7 MPa • s, and supposing the high end at 1.3 MPa • s remains the same, and so is the linear in-betw... click for more

Risk Analysis and Management: Earthquake - An example of Fragility and Load

The fully formated problem is with the solution. The fragility of a building as function of earthquake magnitude is given as follows: • if L  Lf Pf (L) = 1 – exp{ -C(L-Lf)2} • if L < Lf Pf (L) = 0 where L is the magnitude of the earthquake. This fragility curve has two parameters, Lf and C. Lf is the threshold. Any earthquake with magnitude less than Lf will not damage the building. C represents the resistance of the building against earthquake. The larger value of C, the more likely the building will collapse during earthquake. Figure 1 shows Pf (L) as function of Lf and C. Figure 1: Fragility as function of Lf and C. According to expert opinion, the probabili... click for more

Specify Control scheme for a Cryogenic Stripper

Please see the attached file for the fully formatted problem(s). S.17. Sketch a control scheme for the cryogenic stripper shown below that is used for removing small amounts of propane from natural gas. [DIAGRAM] (a) Cooling-water valve V-I is manipulated to control the gas temperature leavü4 the cooler. (b) Valve V-2 controls a temperature on tray 15 in the stripper. (c) Valve V-3 controls the total flow rate of gas into the compressor. (d) Valve V-4 controls the temperature of the propane bottoms product leaving óe unit. (e) Valve V-5 controls the column base level. (f) Valve V-6 controls the liquid level in tank 1. (g) Valve V-i controls the speed of the expander turbin... click for more

Specify Control Scheme for Heat Integrated Distillation Columns

Please see the attached file for the fully formatted problem(s). 8.15. Two distillation columns are heat-integrated as shown in the sketch below. The first column has an auxiliary condenser to take any excess vapor that the second column does not need. The second column has an auxiliary reboiler that provides additional heat if required. Prepare a control concept diagram that includes the following control objectives: (a) Base levels are controlled by bottoms flows. (b) Reflux drum levels are controlled by distillate flows. (c) Reflux flows are flow-controlled. (d) The pressure in the first column is controlled by vapor flow rate to the auxiliary condenser. A low pressure override pi... click for more

Pump Problem: Flow Rate and Elevation Calculation

Ethylbenzene at 40 degrees C is delivered by a pump from a storage tank to a reactor elevated 3.5 m above the pump. The pressure at the inlet to the reactor is 1.5 barg. There is a control valve in the line, with a pressure drop of 0.75 bar across it. the flowrate of ethylbenzene is 8 L/s. What is the maximum flowrate possible with the valve fully open? If the tank is open to the atmosphere, what is the minimum required elevation of liquid in the tank? The tank is at atmospheric pressure. Please explain the procedure used to solve the problem in detail.