3 replies to this topic

[Kjiel]

Hi everybody,

 

This is my first post in this forum. Congratulations to everyone who keep this up. It's a pretty good resource to learn what we like.

 

Let me introduce myself. I'm a chemical engineer student in Spain and I'm working on the final project. It is a design project of a nitric acid production plant. I've been searching for months some data I'm interested in without succeed.

 

I need to calculate the conversion rate of the reaction NO + 1/2O2 -> NO2. Its a inusual reaction because it goes to the right faster at low temperature than at high temperature, below 150 º C there's practically a 100% of NO2 but I need to calculate the conversion rate of NO to NO2 in every heat exchanger where the stream of NO reduces its temperature. For example, the conversion rate of the stream from 925 ºC to 450 ºC (in this particular range of temperature there's barely formation of NO2 but anyway I have to do it), from 450 ºC to 250 ºC, etc. 

 

The best what I've found is this

 

 Sin título.png   58.79KB   1 downloads

 

But honestly, I don't know how to solve it.

 

Sometimes I feel a bit frustrated wanting to find something I need without succeed, among other reasons, either because I don't know the ideal place to search for it or because in scientific publications and elsewhere, there's a lot of formulas and nice graphs but there's no examples or procedures that teachs you to applicate it.

 

I hope you can help me.

 

Thank you so much for your attention.

 

Kjiel.

 

 

[Bobby Strain]

Maybe someone at Monsanto Enviro-Chem or Basf can point you to literature. Also check nitric acid production simulators.

 

Bobby

[thorium90]

Actually you have been staring at your solution all the time. Your picture already tells you that you have a BVP problem and simply using an ODE solver for BYP like bvpinit in Matlab will give the solution. All you need are the boundary conditions which you yourself already stated. If you are not sure how to use a particular solver, you can learn the syntax from their help documentation.

Edited by thorium90, 14 October 2013 - 06:57 AM.

[Kjiel]

Thank you very much both.

 

Finally, I was able to solve the equation with matlab and I got satisfactory results. Sometimes the solution to our problems is in front of our eyes and we don't see them.

 

Thank you again.