Design a pressure vessel that can hold 45 kg of saturated steam at 2.75 MPa (abs) for a chemical process. The shape of the vessel is to be a cylinder with hemispherical ends. The vessel is to have sufficient insulation to maintain equilibrium with a maximum internal heat input of 3000 MW. For the initial phase of this design, determine the thickness of insulation necessary if heat loss were to occur only by conduction with an outside temperature of 22ºC. For this design, examine Section VIII, Division I of the ASME Boiler and Pressure Vessel Code to determine allowable strength and shell thickness. After completing the initial design, repeat your calculations, assuming that the heat transfer from the steam to the inside of the vessel is by condensation with an average heat transfer coefficient from Table 1.4. On the outside, heat transfer is by nature convection with a heat transfer coefficient of 15 W/m² K. Select an appropriate steel for the vessel to guarantee a lifetime of at least 12 years.

Data from in Table 1.4

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TABLE 1.4 Order of magnitude of convection heat transfer coefficients h Fluid Air, free convection Superheated steam or air, forced convection Oil, forced convection Water, forced convection Water, boiling Steam, condensing Convection Heat Transfer Coefficient W/m² K Btu/h ft² °F 6-30 30-300 60-1,800 300-18,000 3,000-60,000 6,000-120,000 1-5 5-50 10-300 50-3,000 500-10,000 1,000-20,000