Problems with Extractive Distillation of C4 to Get Butadiene

[phantom19]

Hello, I am currently being assigned in doing a project entitled "Extractive Distillation of C4 to Obtain Butadiene using DimethylFormamide(DMF)". It was rather challenging and I am heading nowhere as I had take a long time in trying to carry out the material balance. One of the challenges is to receive key data like operating temperature and pressure as well as its vapor and liquid composition after being distilled by different column.

The things go like this:
I am required to design a plant to produce 100kMT of Purified Butadiene annually. The feed consists of Butadiene (x=0.5), 1-Butene(x=0.38), Butane (x=0.1), Vinyl Acetylene (x=0.01), Methyl Acetylene (x=0.009) and water (x=0.001). The feed to the first extractive distillation column is 7 times the raw feed flow.

The problem is:
How should I calculate the vapor composition and liquid composition after the first extractive distillation step as well as its bottom and top temperature noting that the relative volatility of butadiene and vinyl acetylene change significantly (from very volatile to being able to come out in the bottom product, as I understand from literatures...)? I am only allowed to use manual calculation for this purpose and Aspen can only be used to check the accuracy of Manual calculation..can anyone please help me?

Thanks...

 

[nbryan5]

To solve this problem, you need to start with doing a material and energy balance around the distillation column. This will help you determine the relative volatility of each component and the resulting liquid and vapor compositions. The key parameters you need to consider include the distillation column pressure and temperature as well as the feed composition. You can also use thermodynamic models to calculate the relative volatility of each component to help you further refine your calculations. Additionally, you can also use simulation software such as Aspen to check the accuracy of your manual calculations.