Reference no: EM132644027
You can use computer programming to solve the problems.
Question 1. A feed to the column coming 100 kmol/h contains three components n-pentane (A), n-hexane (B) and n-heptane (C). Assume liquid solution follows Raoult's law and Antoine's equation is applicable. Characterize the feed for following compositions (mole fraction) at temperatures 30°C, 50°C, 70°C, 90°C and 110°C:
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1
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2
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3
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4
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5
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A
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0.2
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0.3
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0.2
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0.4
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0.3
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B
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0.2
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0.2
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0.4
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0.3
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0.4
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Calculate the enthalpy of feed, and vapor and liquid products. Estimate q values. Use Cp values from web to calculate enthalpy. Clearly mention the reference temperature.
Question 2. Take feed flow rate = 100 kmol/hr as basis. An equimolar mixture of A and B is to be fractionated in a distillation column. It is equipped with a total condenser and total vaporizer. The mole fraction of the distillate is 0.98 and that bottoms is 0.03. The feed consists of 40% vapor and 60% liquid. The relative volatility of the mixture is 2.5. Locate the pinch point and calculate Rmin. If the column is to be operated at 1.5 Rmin, calculate the liquid and valor flow rates in the enriching and stripping sections of the column andfind the number of theoretical stages required.
Question 3. Assume that the column is equipped with a partial condenser and partial reboiler. Find the required number of ideal stages in the column. Determine the composition of the vapor entering the bottom of the column and liquid entering as reflux.
Question 4. Consider pure B is available as a vapor. It is decided that it would be fed at the bottom of the column instead of using a reboiler. Find the number ideal stages required.
Question 5. Consider that pure A is also available as liquid at the temperature prevailing at the top of the column. It is used for reflux and the condenser is removed. Pure vapor is fed as mentioned in Prob. 4. How many ideal stages would be required and what are the compositions of the bottom and top products and their flow rates?