1. In an ammonia synthesis process, heat integration is essential as there are hot streams to...

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1. In an ammonia synthesis process, heat integration is essential as there are hot streams to be cooled and cold streams to be heated. There are three process streams to be heat integrated. The synthesis gas must be cooled from 871.3 °F to 39.2 °F. The recycled gas must be heated up from 39.2 °F to 102.0 °F. The compressed gas must also be heated up from 146.7 °F to 527.0 °F. As a good process engineer you want to make use of the excess heat to generate as much as possible 1500 psia saturated steam. Two temperature levels of saturated NH3 liquid coolant are available. Cooling water is also available. Design the Heat Exchanger Network and identify the appropriate flow rates of steam, coolants and cooling water. Design Basis: (1) 50 degrees F minimum approach temperature for all heat exchangers except those requiring refrigerants (2) 7 degrees F minimum approach temperature for refrigerant heat exchangers (3) The data are shown in the data table. Ignore the pressure drop. (4) AspenPlus is recommended to simulate the stream duty and flow rate. Data Table: Pressure, psia Inlet Temp, F Outlet Temp. F Flow rate, lbs/hr Mole fraction H₂ N₂ NH3 Argon H20 Deliverables: Syn Comp Recycle Gas Gas Gas 2224 871.3 39.2 443061 2299 146.7 527 443061 2121 39.2 102 346145 .6811 .2284 .5903 .6976 .1980 .2334 .1832 .0438 .0580 .0285 .0252 .0325 Sat'd Liq NH3 Coolant Level 1 ??? 72.8 72.8 ??? 1 Sat'd Liq NH3 Coolant Level 2 ??? 31.8 31.8 ??? 1 Cooling 1500 psia H20 75 95 ??? Saturated H2O 1500 (1) PFD for the heat exchanger network or the snap shot of the simulation (2) Fill the blanks in the data table with questions marks. (3) A table summarizing your heat exchanger designs including duties, inlet and outlet temperatures, log mean temperatures, UA values, etc. ??? 1 1. In an ammonia synthesis process, heat integration is essential as there are hot streams to be cooled and cold streams to be heated. There are three process streams to be heat integrated. The synthesis gas must be cooled from 871.3 °F to 39.2 °F. The recycled gas must be heated up from 39.2 °F to 102.0 °F. The compressed gas must also be heated up from 146.7 °F to 527.0 °F. As a good process engineer you want to make use of the excess heat to generate as much as possible 1500 psia saturated steam. Two temperature levels of saturated NH3 liquid coolant are available. Cooling water is also available. Design the Heat Exchanger Network and identify the appropriate flow rates of steam, coolants and cooling water. Design Basis: (1) 50 degrees F minimum approach temperature for all heat exchangers except those requiring refrigerants (2) 7 degrees F minimum approach temperature for refrigerant heat exchangers (3) The data are shown in the data table. Ignore the pressure drop. (4) AspenPlus is recommended to simulate the stream duty and flow rate. Data Table: Pressure, psia Inlet Temp, F Outlet Temp. F Flow rate, lbs/hr Mole fraction H₂ N₂ NH3 Argon H20 Deliverables: Syn Comp Recycle Gas Gas Gas 2224 871.3 39.2 443061 2299 146.7 527 443061 2121 39.2 102 346145 .6811 .2284 .5903 .6976 .1980 .2334 .1832 .0438 .0580 .0285 .0252 .0325 Sat'd Liq NH3 Coolant Level 1 ??? 72.8 72.8 ??? 1 Sat'd Liq NH3 Coolant Level 2 ??? 31.8 31.8 ??? 1 Cooling 1500 psia H20 75 95 ??? Saturated H2O 1500 (1) PFD for the heat exchanger network or the snap shot of the simulation (2) Fill the blanks in the data table with questions marks. (3) A table summarizing your heat exchanger designs including duties, inlet and outlet temperatures, log mean temperatures, UA values, etc. ??? 1

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Designing a heat exchanger network and determining the appropriate flow rates of steam coolants and cooling water requires a thorough analysis of the ... View the full answer