A 3-unit process (2 evaporators and 1 mixer) is used to concentrate salt water. 2000 kg/min of a NaCl/water solution of unknown mass fractions is flowed into an evaporator, where 500 kg/min of pure water is removed as vapor. The concentrated solution stream is sent to a mixer, where 1000 kg/min of a 20 wt% NaCl solution in water is added. The mixture is then sent to an evaporator, where 1000 kg/min pure water is removed as vapor. The final stream contains 50 wt% NaCl in water at an unknown total flow rate. Which of the following unit balances has 0 DOF?
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Question

A 3-unit process (2 evaporators and 1 mixer) is used to concentrate salt water. 2000 kg/min of a NaCl/water solution of unknown mass fractions is flowed into an evaporator, where 500 kg/min of pure water is removed as vapor. The concentrated solution stream is sent to a mixer, where 1000 kg/min of a 20 wt% NaCl solution in water is added. The mixture is then sent to an evaporator, where 1000 kg/min pure water is removed as vapor. The final stream contains 50 wt% NaCl in water at an unknown total flow rate. Which of the following unit balances has 0 DOF?
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anonymous · Answer

@Photon336

anonymous · Answer

@ganeshie8 are you good at material balances?

photon336 · Answer

I'm not that familiar with these types of problems but I can attempt this. what is DOF?

photon336 · Answer

@Michele_Laino @mayankdevnani

michele_laino · Answer

I'm very sorry, I don't know that answer

michele_laino · Answer

maybe DOF stands for $D$egree $O$f $F$reedom, nevertheless I'm not sure

mayankdevnani · Answer

I don't know if i am correct,can we change the given conversion into molarity ?

anonymous · Answer

its like creating a flow chart idk, im ery confused with a poor teacher

photon336 · Answer

This is what the problem looks like to me 

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